Inappropriate use of antibiotics in children is common in many countries. The purpose of the study was to explore patterns of antibiotic prescribing in children’s outpatient clinics in primary care institutions in a province of southwest China.We obtained electronic prescription data from 75 primary care institutions in Guizhou province in 2020. The classification of incorrect spectrum of antibiotics, unnecessary use and combined use of antibiotics was based on the Guiding Principle of Clinical Use of Antibiotics  and guidelines from the USA Centers for Disease Control and Prevention. Potential risk factors for inappropriate use of antibiotics were identified using bivariate analyses. The generalized estimation equation was used to identify independent predictors of inappropriate use of antibiotics.A total of 158,267 antibiotic prescriptions were retrieved. Acute upper respiratory tract infections were the most common diseases, accounting for 74.9% of all prescriptions. The main antibiotic group used was penicillins (63.7%), followed by cephalosporins (18.8%). Of 137,284 visits, 18.3% of antibiotic prescriptions were appropriate and the percentage of unnecessary use, incorrect spectrum of antibiotics and combined use of antibiotics was 76.9, 2.4 and 2.4%, respectively. Physicians with lower professional titles and more than 40 years of work duration were relatively more likely to prescribe inappropriate antibiotics.The inappropriate use of antibiotics in children is still prominent in primary care institutions of southwest China. The education and training of physicians and caregivers in these institutions should be strengthened.The online version contains supplementary material available at 10.1186/s12875-022-01875-9. Antibiotic resistance (ABR) has become a major challenge in the field of global public health . InapproThe appropriate use of antibiotics in children is critical because there are limited formulations of antibiotics suitable for this population , 18. StuThis study reviewed the antibiotic prescription data of children in outpatient clinics of primary care institutions in Guizhou, southwest China in 2020. The objective of the study was to explore patterns of antibiotic prescribing in children’s outpatient clinics in primary care institutions.The study was approved by the Review Committee of Guizhou Medical University ). All participants (physicians) provided written informed consent to participate in the study.A retrospective study was conducted in Guizhou, one of China’s poorest provinces. Antibiotic prescribing patterns for children in primary care institutions were quantified from January to December 2020. The main influencing factors of inappropriate use of antibiotics were explored.This study has been authorized by the Information Center of Guizhou Provincial Health Commission. A data collection agreement was reached with the Guizhou LianKe Weixin Co., LTD. (LWTC), which developed the electronic Hospital Information System (HIS). The data was obtained through the data port of the information center.China’s 3-tier hospital system, from top to bottom, includes: tertiary hospitals, secondary hospitals, and primary hospitals. Primary care institutions, which include township health centers and community health service centers, belong to primary hospitals . In 2020the United Nations Convention on the Rights of the Child [Law of the People’s Republic of China on the Protection of Minors [the 10th Edition of the International Classification of Diseases (ICD-10) [the 2018 National Catalogue for Clinical Application of Antibacterial Drugs  . AccordiGuiding Principle of Clinical Use of Antibiotics introduced in 2015  Guidelines for use of antibiotics [Streptococcus pneumoniae at present are highly resistant to these two antibiotics groups, and are generally not used) also can be used or substituted. Nitroazoles mainly target anaerobic bacteria, and aminoglycosides have poor antibiotic effect on Streptococcus pneumoniae group A hemolytic streptococcus. The use of nitroazoles and aminoglycosides in treatment was regarded as incorrect spectrum of antibiotics., and 3) combined use of antibiotics: more than one systemic antibiotic by injection or oral administration at a time by an outpatient physician without any indication, e.g., amoxicillin capsule and ceftazidime injection combined.Our evaluation of the appropriateness of antibiotic prescription was mainly based on the following three aspects: 1) National Health Commission of China for ibiotics , and 3) ibiotics , we alsoibiotics , 28 to jP-values were two-sided. R version 4.1.2 was used for all data management and analysis.All prescriptions were linked to physicians and patients through coding identification, forming a database of medical service information. A physician can prescribe one or more antibiotics to a patient in a day, but multiple visits per patient per day count as only one visit. Antibiotic prescribing patterns were determined by performing bivariate cross-tabulations between ICD-10 disease classification and antibiotic groups. Potential risk factors for inappropriate use of antibiotics were also identified using a bivariate cross-tabulation. In order to explain the correlation between antibiotic prescriptions prescribed by the same physician and to avoid possible confounding effects of other variables, the generalized estimation equation (GEE) approach was used to identify independent predictors for inappropriate use of antibiotics. All During the study period, 158,267 antibiotics prescribed to 143,809 patients aged 18 years and under were obtained from the HIS. After excluding 823 antibiotic prescriptions labeled in other categories and 2310 topical antibiotic prescriptions, there were 155,134 prescriptions remaining among 143,257 patients. For the purposes of this analysis, only patients who were diagnosed with any of the top 10 common systemic diseases were included in the study, resulting in a total of 150,133 antibiotic prescriptions (96.8%).Figure Table The highest rate of inappropriate use was seen for symptoms, signs and abnormal clinical and laboratory finding not elsewhere classified (100%), diseases of the circulatory system (96.9%), and diseases of the skin and subcutaneous tissue (88.6%). Incorrect spectrum of antibiotic was common for children with diseases of the eye and adnexa (37.1%), certain infectious and parasitic diseases (13.2%), and diseases of the ear and mastoid process (6.1%). The unnecessary use of antibiotics for diseases of the ear and mastoid process and diseases of the eye and adnexa was 12.6% and 8.5%, respectively. Unnecessary use of antibiotics for the other eight systemic diseases exceeded 50%. Diseases of the ear and mastoid process (81.3%), diseases of the eye and adnexa (54.5%) and injury, poisoning and certain other consequences of external causes (47.2%) were the top three ranked diseases in terms of appropriateness of antibiotics use.P <  0.001). Therefore, all variables were included in the multivariate analysis.Table Table In this retrospective study, 75 primary care institutions in Guizhou Province were selected to describe the prescription patterns of antibacterial drugs among children in 2020. Overall, the rate of antibiotic prescriptions was highest in the fourth quarter, followed by the first quarter. Among the antibiotics prescribed, penicillins and cephalosporins were the most used antibiotics groups. The most common childhood diseases were the diseases of the respiratory system (86.8%), followed by diseases of the digestive system (6.0%) and diseases of the skin and subcutaneous tissue (2.1%). Overall, 80.5% of antibiotic prescriptions were inappropriate. Physicians with lower professional titles and more than 40 years of work duration were relatively more likely to prescribe inappropriate antibiotics.acute upper respiratory infections of multiple and unspecified sites  and acute tonsillitis  were the most common upper respiratory diseases for which antibiotics were administered in children, accounting for 72.4%. A study from China reported an antibiotic prescription rate for acute upper respiratory tract infections in children of 77.6% while in other countries reported rates ranged from 28.7% (Japan) - 76.2% (Albania) [In this study, Albania) –34. HoweAlbania) , PracticAlbania)  and the Acute upper respiratory infections of multiple and unspecified sites) does involve prescription of all antibiotics need not be used (U: unnecessary use). For J03 (Acute tonsillitis), penicillin is preferred in more severe cases where bacterial infection is suspected  (P: preferred medication). Cephalosporins, macrolides, and quinolones also can be used. If lincosamides, aminoglycosides and nitroimidazoles were used, the antibiotic spectrum is incorrect (I: incorrect spectrum of antibiotics).Therefore, in Table acute bronchitis (15.2%) and bronchitis, not specified as acute or chronic (4.8%), was the second most common childhood disease class in our study. Studies in China [Acute bronchitis) shows that all antibiotics need not be used (U: unnecessary use). For J40 , penicillins, cephalosporins, macrolides and quinolones shown antibiotic can be used or substituted (A: antibiotic can be used or substituted). If lincosamides, aminoglycoside, nitroimidazole were used, the antibiotic spectrum is incorrect (I: incorrect spectrum of antibiotics).Lower respiratory tract infections, which include in China , Japan [in China  and Franin China  found thin China . Therefoonchitis 5.2% and acute upper respiratory tract infections of multiple and unspecified sites (J06) or acute bronchitis (J20) is inappropriate because it may trigger allergies, infections, and even endanger the child’s life [The use of antibiotics for d’s life . This scd’s life .In this study, the number of children diagnosed with acute otitis media and urinary tract infections was lower than other studies , 40. Altsymptoms, signs and abnormal clinical and laboratory findings not elsewhere classified  were all diseases for which antibiotics are unnecessary. The rate of inappropriate antibiotics use for these diseases often reached 100%. When treating such childhood diseases, physicians should make specific clinical diagnoses based on typical signs and symptoms [Overall, the unnecessary use of antibiotics occurred in all 10 systemic disease classifications in the study, accounting for 63.6% of all antibiotic prescriptions. This included diseases of the respiratory system , diseases of the digestive system , diseases of the skin and subcutaneous tissue , symptoms, signs and abnormal clinical and laboratory findings not elsewhere classified , injury, poisoning and certain other consequences of external causes , diseases of the genitourinary system , diseases of the circulatory system , diseases of the ear and mastoid process , certain infectious and parasitic diseases , and diseases of the eye and adnexa (H02). It should be noted that the 10 sub-diseases under symptoms , 28. It symptoms . Accordisymptoms . Physicithe systemic disease of symptoms, signs and abnormal clinical and laboratory findings not elsewhere classified, the other 9 systemic diseases all had the condition of incorrect spectrum of antibiotics. Diseases of the eye and adnexa had the highest proportion of incorrect spectrum of antibiotics (37.0%). The proportion of incorrect spectrum of antibiotics was highest in the sub-disease (keratitis) of diseases of the eye and adnexa (97.8%). Penicillins, cephalosporins, macrolides, lincosamides and nitroimidazoles are the incorrect spectrum of antibiotics for these particular diseases. According to Ophthalmology Clinical Guidelines of American Academy of Ophthalmology (2nd edition) [Ophthalmology of China (9th edition) [National Health Commission of China for Guiding Principle of Clinical Use of Antibiotics introduced in 2015 [keratitis treatment, especially in children.We also found from those antibiotic prescriptions with incorrect spectrum of antibiotics accounted for 2.4% of all antibiotic prescriptions. Except for edition) , Ophthaledition)  and Nati in 2015 , quinoloIn our study, “Incorrect spectrum of antibiotics” (2.4%) and “Combined use of antibiotics” (2.4%) were the two types of inappropriate antibiotics use that accounted for the least proportion. The proportion of “Incorrect spectrum of antibiotics” in this study was low, mainly because the proportion was distributed differently among different diseases. For example, the proportion for keratitis and acute myocarditis was more than 75% of cases. The low inappropriate rate of “Combined use of antibiotics” was primarily due to the absence of diseases such as tuberculosis, leprosy or other diseases requiring combination therapy in primary care institutions . In addiIn our study, the majority of inappropriate antibiotic prescriptions were prescribed by physicians older than 40 years, with lower professional titles (resident physician / attending physician) and more than 40 years of work duration. Their education was mostly non-undergraduate, and their professional knowledge and experience are often inadequate. Based on this result, it may be necessary to provide refresher courses in antibiotic prescribing for these primary care physicians , 48. TraIn this study, children insured by new rural cooperative medical system were more likely to be prescribed inappropriate antibiotics than those who had to pay fully out-of-pocket. One possible reason is that many antibiotics in China are included in the National Essential Medicine List . The chiThe proportion of antibiotics prescribed inappropriately was higher in the third and fourth quarters compared to the first quarter of the year. This may be due to the higher incidence of infectious diseases in autumn and winter . HoweverWe also found that inappropriate antibiotic prescriptions in children may be correlated with sex of children. This may be related with the fact that left-behind children in rural areas of China are often cared for by poorly educated grandparents, as well as sex discrimination. In addition, children aged 0–1 were more likely than any other age group to be prescribed inappropriate antibiotics. In our team’s preliminary survey of primary care institutions in Guizhou Province, we found that the educational level of child caregivers was low and were unaware of the dangers of antibiotic resistance. They generally believe that antibiotics are a panacea. However, infants have an immature immune function, weak anti-infection ability, and are prone to various diseases . In ordeIn China, during the COVID-19 pandemic in 2020, the National Health Commission noted that primary care institutions had the lowest level of access and treatment conditions than secondary and above hospitals. Therefore, they were not eligible for COVID-19 treatment. All suspected febrile patients are transferred to a secondary or higher-level hospital for treatment. Therefore, there were no febrile patients in outpatient clinics of primary care institutions. No COVID-19 related patients were seen in this study.Our study has several limitations. First, the study subjects in primary care institutions may not fully represent the general population of children in China. Second, the time frame of the survey was limited to 1 year, thus we could not judge whether the prevalence of pediatric diseases and antibiotic use differed over several years , 54. ThiThe inappropriate use of antibiotics in children is still prominent in primary care institutions in Guizhou, China. Unnecessary use of antibiotics for many diseases and the inappropriate use of lincosamides and aminoglycosides in children in primary care were the main clinical problems of rural children. The education and training of physicians and caregivers in primary care institutions should be strengthened.Additional file 1. Catalogue for Clinical Application of Antibacterial Drugs.Additional file 2. National Health Commission of China for Guiding Principle of Clinical Use of Antibiotics.


Heroin, a semisynthetic opioid drug synthesized from morphine, is the 3,6‐diacetyl ester of morphine (diacetylmorphine). The post‐mortem diagnosis of heroin‐related death could be an issue and usually rely on a combination of investigations, including the autopsy, histological and toxicological analysis. We conducted the present study to evaluate the correlation between the heroin concentration in biological fluids  and the post‐mortem anti‐6‐MAM antibody expression in various tissues  using immunohistochemical staining. A quantitative analysis of the immunohistochemical reaction was carried out. 45 cases of heroin‐related death investigated at the Forensic Pathology Institutes of the University of Rome, Foggia and Pisa were included. The control group was composed of 15 cases of death due to other causes, without brain lesions and negative toxicological analysis for drugs. We found a positive immunohistochemical reaction in different organs and it was related to the timing of heroin metabolization. No reaction was found in the control group. Our findings show that immunohistochemistry can be a valuable tool for the post‐mortem diagnosis of acute heroin abuse. A better understanding of the timing of heroin's metabolism can be useful in the forensic field and for future therapeutic applications. Commercial heroin is diluted with sugars and adulterated with local anaesthetics, amphetamine‐like substances, cocaine and caffeine.Toxicology data is certainly of greater importance for the diagnosis of heroin‐related death. Several implications for research arise from the literature on deaths attributed to heroin overdose because blood morphine alone often cannot explain the fatal event.The aim of this study was to clarify the correlation between heroin administration and the distributive response in heroin‐related death, as well as to investigate the correlation between heroin blood concentration and the immunohistochemical features of various tissues through an anti‐6‐MAM antibody.2The processing of the data reported in this paper is covered by the general authorization to process personal data for scientific research purposes granted by the Italian Data Protection Authority  since the data do not entail any significant personalized impact on data subjects. Our study does not involve the application of experimental protocols; therefore, it does not require approval by an institutional and/or licensing committee nor informed consent. In all cases, local prosecutors opened an investigation, ordering that an autopsy be performed to clarify the exact cause of death.2.1The toxicological data and the autopsy records of the 204 autopsies of drug‐related death performed at the Departments of Forensic Pathology of the University of Rome, Foggia and Pisa over the period 2014–2021 were evaluated, and 45 cases of heroin‐related death were selected . The autopsy was performed within 36 h after death. Only cases with toxicological data positive for heroin and negative for any other drug (ethanol included) were selected. Post‐mortem examination confirmed the diagnosis of heroin‐related death in all the cases. Toxicological analyses were performed on peripheral blood, bile, and urine by gas chromatography‐mass spectrometry (5977A Series Agilent). The mean concentrations of free‐morphine, total‐morphine, and 6‐monoacetylmorphine are reported in Table n = 3) and sudden cardiac deaths (n = 2) with no clinical history, without brain lesions and negative toxicological analysis for drugs. Those deaths were characterized by their rapidity.All cases were HIV‐1 negative. The control group was composed of 15 cases  that died from car accidents , heart, lung, liver and kidney. In the literature, there were no indications on the best method to be used in immunohistochemistry with the Polyclonal 6‐Monoacetylmorphine; antibody Ig fraction supplied in liquid form in 20 mM phosphate buffer, 150 mM sodium chloride and 0.09% sodium azide, pH 7.2 . Lacking other similar experimental studies, we had to establish from scratch an adequate method and the appropriate dilution of the antibody.Samples of each organ from each case were fixed in 10% buffered formalin, then washed with phosphate‐buffered saline (PBS) and subsequent dehydration was carried out using a graded alcohol series. After dehydration, samples were cleared in xylene and embedded in paraffin. Sections were cut at 4 μm, mounted on slides, and covered with 3‐amminopropyltriethoxysilane (Fluka). The sections were pretreated with endogenous peroxidase activity, incubated with the anti‐6‐Monoacetylmorphine antibody diluted 1:100. After removal of the primary antibodies with three 5‐min washes in PBS, sections were incubated for 40 min with biotinylated horse anti‐mouse IgG (Vector) diluted 1:200 in 1% NHS. After three 5‐min washes in PBS, sections were incubated for 30 min with horseradish peroxidase avidin D  diluted 1:1000 with PBS. After three 5‐min washes of PBS, the sections were developed with the DAB kit (Vector), stopped with rinses of double‐distilled water.Routine microscopic histopathological studies were performed using formalin‐fixed paraffin‐embedded tissue sectioned at 4 μm and stained with haematoxylin‐eosin (H & E). The specimens were examined under transmitted bright field illumination and phase contrast mode using a light microscope (DM 4000 B Leica) connected to a photo camera computer system (DC 480 Leica). Three‐dimensional reconstruction of tissues utilizing a confocal microscope  was performed.The immunohistochemical findings and the gradation of the immunohistochemical reaction have been described with an ordinary scale and the median value has been reported. For the quantitative analysis, in each immunohistochemical section, we made 20 observations in different fields/slides. The 6‐Monoacetylmorphine‐stained cells were counted at 60× using a light microscope coupled to a high‐resolution colour video camera. The reactions were graded as follows: 0. (−) not expressed; 1 (+) isolated and disseminated expression; 2 (++) expression in scattered foci; 3 (+++) expression in widespread foci; and 4 (++++) widespread expression. The evaluations were carried out separately for each tissue, using a double‐blind method. In cases of divergent scoring, a third observer decided the final score.3In our study, samples obtained from 45 cases of acute heroin‐related death, with negative toxicological analysis for other drugs, were analysed through immunohistochemistry to evaluate the pattern of heroin distribution in various tissues. The immunohistochemical technique allowed us to quantify the expression of the response, as shown in Table The positive reaction in the different organs was related to the timing of heroin metabolization, being most positive in the brain and lungs in the earliest intakes, while the highest positivity in the liver and kidneys was found in cases where the heroin was already metabolized and being excreted. The anti‐6‐MAM antibody exhibited no reaction in organs or blood vessels of cadavers who died from non‐heroin‐related death (control group). Table 4We used an experimental model and immunohistochemistry to investigate the post‐mortem anti‐6‐MAM antibody expression and localization in heroin‐relation death cases. Our preliminary study's objective was to find out if immunohistochemistry, using an anti‐6‐MAM antibody, could represent an effective means to diagnose acute heroin abuse. In brain tissue, extensive 6‐MAM‐reaction positivity and microglial or astroglial reaction, or both, were detected in all the investigated cases.Additionally, our findings on lung samples showed positivity in the cytoplasm of macrophages and intra‐alveolar spaces can be correlated with acute respiratory depression heroin‐related death.As Büttner stated, up to 90% of all cases of heroin‐related death show brain oedema with prominent tonsillar herniation and uncal grooving at autopsy.Katz et al. in 1972 highlighted the role of heroin in increasing pulmonary alveolocapillary permeability and together with a loss of albumins in the oedema fluid.In the kidneys, related microscopic changes to the use of heroin are defined as ‘heroin‐associated nephropathy’.One limitation of our study is the relatively small sample size. Precise criteria, however, were used for selecting subjects. Also, detailed immunohistochemical anti‐6‐MAM studies are not available, which precluded a comparison of our observations with others. However, it is important to highlight that this study opens new perspectives in the post‐mortem diagnosis of heroin‐related death, introducing a new, promising diagnostic tool, especially when toxicological data are not available. The results of our immunohistochemical study have shown a good correlation with the toxicological data. Moreover, elucidating the timing of heroin's metabolism may influence therapeutic strategies.In conclusion, our findings show that immunohistochemistry with the anti‐6‐MAM antibody can be a valuable aid for the post‐mortem diagnosis of acute heroin abuse. The specimens were examined by confocal laser scanning microscopyAniello Maiese: Conceptualization ; Formal analysis ; Writing; Validation . Raffaele La Russa: Methodology; Formal analysis . Maria Chiara David: Data curation . Santina Cantatore: Data curation ; Software. Alice Chiara Manetti: Writing – original draft . Alessandra De Matteis: Writing – original draft . Costantino Ciallella: Writing – review & editing . Paola Frati: Validation ; Writing – review & editing . Vittorio Fineschi: Conceptualization ; Supervision; Project administration.The authors confirm that there are no conflicts of interest.


Based on the tests, it was found that the total addition of siliceous materials, i.e., SF + nS without FA, increases the strength and fracture parameters of concrete by approximately 40%. On the other hand, supplementing the composition of the binder with SF and nS with 5% of FA additive causes an increase in all mechanical parameters by approximately 10%, whereas an increase by another 10% in the FA content in the concrete mix causes a significant decrease in all the analyzed factors by 10%, compared to the composite with the addition of silica modifiers only.This study presents test results and in-depth discussion regarding the measurement of the fracture mechanics parameters of new concrete composites based on quaternary blended cements (QBC). A composition of the two most commonly used mineral additives, i.e., fly ash (FA) and silica fume (SF), in combination with nanosilica (nS), has been proposed as a partial replacement for ordinary Portland cement (OPC) binder. Four series of concrete were made, one of which was the reference concrete (REF) and the remaining three were QBC. During the research, the main mechanical parameters of compressive strength ( Building structures made of concrete composites effectively protect the occupants against rain, moisture, noise, cold, or temperature fluctuations ,2. In adUnfortunately, the production process of concrete, which is currently the most utilized basic construction material, is fully against the principles of sustainable development, generating identifiably negative effects on the natural environment. The impact of the lack of ecological production of this very useful construction material concerns mainly the cement matrix of the concrete composite ,7,8,9,102), during this process [Ordinary Portland cement (OPC), which is the basic binding agent in the production of concrete composites, is formed as a result of burning Portland clinker, which generates significant amounts of harmful greenhouse gases, mainly carbon dioxide  ;Silica fume (SF) ;Ground or granulated blast-furnace slag (GGBS) ;Nanosilica (nS) ;C-S-H nanoseeds ,64;Waste glass, limestone powder, crumb rubber, and others ,66.The most frequently used SCMs currently include:In addition, synthetic fibers, including polypropylene, basalt, and polyvinyl alcohol (PVA) fibers, can be used in cementitious composites to improve the anti-cracking performance and fracture toughness of the matrix ,68,69,70Unfortunately, a significant factor thus far inhibiting the development of concrete composite production based on multi-component cements is the lack of practical knowledge related to the use of binders of this type in concrete technology. Therefore, this paper presents comprehensive examinations of the fracture mechanics parameters of concrete composites made of quaternary blended cements (QBC).CTODc) of gravel concrete containing SF were investigated in two studies [KIc and CTODc, as well as the fracture energy (GF), were also analyzed.It should be mentioned that the fracture toughness of concretes containing only FA or SF has been the subject of previous studies. The synergy of the interactions of these two SCMs, in the context of the fracture toughness of concrete, has also been studied. Thanks to previous experiments, for example, the optimal amount of FA in the context of improving fracture resistance and toughness—the critical stress intensity factor  based only on OPC,three composites made of quaternary blended cements (QBC), based on OPC and enhanced by FA, SF, and nS.However, a new type of cementitious composite in terms of fracture toughness was examined in the current article. The cement matrix in the composites in question was made on the basis of OPC, in connection with two main additives, i.e., FA and SF, and a nanoadditive in the form of nS. In order to track the various components of SCMs, four series of concretes were made, including:2 emissions released into the atmosphere, which will be a significant step toward the further development of sustainable construction.The conclusions resulting from the research undertaken—in terms of the synergy of the impact of SCMs on the fracture processes in cementitious composites with a diversified binder composition—may contribute in the future to a more conscious use of such materials in composite structures. Undoubtedly, this will positively affect the reduction of CO3—in the form of a coarse aggregate,natural gravel, with grain diameters ranging from 2.0 to 8.0 mm and with a specific gravity of 2.65 g/cm3—in the form of a fine aggregate.pit sand with a maximum size of 2.0 mm and with a specific gravity of 2.60 g/cmThe following types of aggregates were used in the studies:OPC CEM I 32.5 R, produced by the Chełm cement plant,Class F FA, produced by Puławy thermal-electric power station,non-condensed SF, obtained from Łaziska Ironworks,nS Konasil K-200, produced by the OCI Company Ltd .In order to prepare the concrete mixtures, four types of binders were used, including:The chemical compositions of all binders, evaluated using X-ray fluorescence (XRF), are shown in The water used in this experiment is from a domestic water supply that meets the requirements of European Standard EN 1008:2002, i.e., “Mixing water for concrete” .A superplasticizer (SP), STACHEMENT 2750, based on polycarboxylates was used in order to improve the flowability of the concrete. The SP accounts for 1.8% of the binder mass, with a very high liquefaction effect that is retained for a longer period than with the more commonly used superplasticizers.CTODc, as well as the compressive strength, fcm, and the splitting tensile strength, fctm, were conducted on four types of concrete composites containing different amounts of the OPC and the additives.Fracture toughness tests to estimate the critical stress intensity factor, The stages of the mixing procedure of concrete components, including the duration of all of the necessary works, are presented in CTODc.The total time for preparing the concrete mix is approximately 9–10 min . After fAfter finishing, the specimens were covered with wet fabric and stored in the casting room at 20 fcm,EN 12,390-3:2011 + AC:2012 —in the cfctm.EN 12,390-6:2009 —in the cDuring the studies, mechanical property tests were carried out according to the European Standards, i.e.:Both the mechanical parameters were determined with the use of a Walter + Bai AG hydraulic servo-testing machine, with a maximum bearing capability of 3000 kN and with the application of cubic specimens (150 mm). Six specimens were prepared for each mixture ratio and for both mechanical tests. Therefore, the mean value of the 6 results was taken for the purpose of analysis. During both compression-strength tests and splitting tensile strength tests, the specimens were loaded statically.0 = 50 mm —crack mouth opening displacement (CMOD); F–CMOD, and the detailed formulas can be found in [Fmax, loading the specimen,maximum force—F–CMOD relationship in the first (Ci) and second (Cu) phases.a tangent of the The analyzed fracture mechanics parameters, i.e., found in . Moreovefound in , i.e.:maWThe critical stress intensity factor tion (1) :(1)KIcS=CTODc, was determined from Equation (2) [The second of the analyzed fracture mechanics parameter, i.e., the critical crack tip opening displacement, tion (2) :(2)CTODcfcm and fctm for all QBCs. Additionally, the upward trends for both analyzed parameters were strictly consistent with each other between the individual materials.The results of the tests of the basic strength parameters of concretes with variable structures in terms of the cement matrix are shown in The highest compressive and splitting tensile strengths were obtained for the concrete mixed with the addition of three different SCMs in the composition of the cement matrix . For theThe obtained test results of the mechanical parameters can be explained by the fact that the FA additive, used in small amounts, is able to additionally produce a larger amount of more compact C-S-H phase, which makes the material more airtight by filling the material’s pores ,83. Howefcm and fctm, compared to QBC-3. Nevertheless, the results for this material were clearly lower than the values obtained for the matrix-based composite, which was composed of 70% OPC + 5% FA + 10% SF + 5% nS . However, the character of the destruction of this composite was similar to the behavior of the quasi-plastic material, although not as evident as in the case of composites with the FA additive  samples corresponded to the typical failures for ordinary unmodified concrete. In this concrete, the exposed aggregate grains were visible and its destruction occurred mainly through the failure of the cement matrix. Therefore, besides a great deal of exposed aggregate, cavities in the areas of separation of gravel grains from the weak cement matrix were also observed a.For concrete from the QBC-1 series b and parOn the other hand, concrete with a higher content of FA was characterized by a porous structure, visible damage in the ITZ area, and few broken aggregate grains d. The faCTODc results obtained for this material were approximately 10% higher compared to the values obtained for QBC-1 and approximately 20% higher than for QBC-2. Moreover, the values for each of the analyzed indicators were higher by approximately 50%, compared to those obtained for the reference concrete ; therefore, the experiments were also scheduled taking into account the important principles of sustainable development.improves the efficiency of OPC production;2 emissions and energy consumption during the production process of OPC;provides a significant reduction in COmeets the demands of ecology;is in harmony with the guidelines of sustainable development.It should be emphasized that increasing the share of SCMs in OPC:The substitution of OPC with the FA + SF + nS combination causes a clear change in the mechanical parameters and fracture toughness of the QBCs.approximately −40% for QBC-1,approximately 50% for QBC-2 andapproximately 30% for QBC-3.Modification of the binder composition with three pozzolanic active materials resulted in an increase in the analyzed fracture mechanics parameters for each of the combinations, compared to the results obtained for the reference concrete see  of:approfcm and fctm, were qualitatively consistent with the results of the fracture mechanics parameters, CTODc (The obtained results for the basic strength parameters, nd CTODc .In the case of concrete from series QBC-1, the development of cracking progressed quite quickly similar like in the completely brittle materials, whereas the addition of FA to the QBC changes the fracture development process in these materials from brittle to quasi-plastic b.F–CMOD curves were clearly sloped and the process of fracture development, from the occurrence of Fmax force to the destruction of the specimens, lasted significantly longer than in the case of QBC-1, with a slow increase in strain at subsequent stages of their loading. The energy leading to the final destruction of the specimens was successively accumulated by the material and was used for the development and propagation of intra-material cracks that ran steadily; additionally, it was at a high level of Fmax for QBC-2 (The addition of FA to the QBC changes the fracture development process in these materials. The or QBC-2 c. This por QBC-2 c.As the content of FA rose throughout each of the QBC series, the material became more ductile and showed less brittle failure .Therefore, based on the conducted studies, the following conclusions can be formulated:


Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a systemic disease that involves the infiltration of IgG4-positive plasma cells in multiple organs. Kimura disease (KD) presents as subcutaneous masses on the head and neck, frequently accompanied by eosinophilia and high immunoglobulin E (IgE) levels. Here, we report a rare case of concurrence of IgG4-RD and KD with manifestations of asthma, pulmonary embolism, and central diabetes insipidus accompanied by lung carcinoma.A 65-year-old Chinese male with an eight-year history of KD was admitted to our hospital with complaints of dyspnea and expectoration for one month. Laboratory examination showed a considerable elevation in the serum eosinophil count and total IgE and IgG4 levels. Chest enhanced computed tomography showed filling defects in the right pulmonary artery and a nodule in the left inferior lobe. Pancreatic enhanced magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography showed a swollen pancreatic tail and local stricture of the pancreatic duct section of the common bile duct. Enhanced MRI of the pituitary gland showed thickening of the pituitary stalk. Additionally, immunohistochemistry of the specimens collected eight years prior revealed IgG4-positive cells. Following the diagnosis of IgG4-RD with KD, glucocorticoids with immunosuppressants were initiated; there was a prompt improvement in the patient’s condition. One-year post-discharge, the patient underwent wedge-shaped resection of the lung due to enlargement of the pulmonary nodule, and the pathology revealed lung squamous carcinoma.This case presents a rare clinical condition in which the concurrence of IgG4-RD and KD causes various rare manifestations including asthma, pulmonary embolism, central diabetes insipidus, and complicated lung carcinoma. This highlights the importance of monitoring for malignancies in IgG4-RD patients during follow-up. Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a systemic inflammatory disease that usually involves multiple systems; it is characterized by elevated serum IgG4 levels, infiltration of IgG4 positive plasma cells, and tissue fibrosis and sclerosis. It often affects multiple organs such as the pancreas, biliary tree, aorta, retroperitoneum, lung, salivary and lacrimal glands, thyroid, kidney, meninges, pituitary gland, and other organs. The pathological features are lymphoplasmacytic infiltration of IgG4-positive plasma cells with storiform fibrosis and obliterative phlebitis . KD is aA 65-year-old Chinese male with an eight-year history of KD was admitted to our hospital on October 16, 2018, with chief complaints of cough and dyspnea over the previous month. The patient was first admitted to the department of stomatology of our hospital due to an enlarged painless right submaxillary mass in August 2010. The histopathological examination of the submaxillary mass showed preserved nodal architecture, florid germinal center hyperplasia, and eosinophilic infiltration Fig. . The patOn admission, his vital signs were as follows: temperature, 36.0 °C; respiration rate, 18 breaths per minute; pulse, 73 beats per minute; and blood pressure, 120/60 mmHg. A painless, right submaxillary mass with a diameter of approximately 2 cm was palpable. He had reduced breathing sounds in both lungs without wheezing or rubs. No swelling was found in the lower limbs.9/L, that was slightly increased. Considering dyspnea accompanied by elevated serum IgE and eosinophil levels, pulmonary function tests were performed. The findings of pulmonary function tests revealed obstructive ventilation function disturbance with a positive bronchial dilation test. A diagnosis of bronchial asthma was considered. To further investigate the potential cause of hypereosinophilia, bone marrow biopsy was performed. It indicated active granulocytic proliferation and an increased proportion of eosinophils.The main laboratory findings are shown in Table The level of serum D-dimer was elevated at 1109 μg/L. The patient had symptoms of dyspnea and elevated serum D-dimer level; therefore, we could not rule out pulmonary embolism. We performed chest enhanced computed tomography (CT), which showed filling defects in the right pulmonary artery and a nodule (1.4 cm × 0.9 cm) in the left inferior lobe basal segment Fig. A, B. TheUrinalysis showed reduced urine-specific gravity at 1.003. However, the renal function (serum BUN and serum creatinine), blood glucose, serum electrolytes , and serum hormonal  levels were within normal limits. Polydipsia, polyuria, and reduced urine-specific gravity were indicative of diabetes insipidus. Further investigations indicated decreased urinary osmotic pressure (140 mOsm/kg), which was lower than the plasma osmotic pressure (288 mOsm/kg). Enhanced MRI examination of the head showed pituitary stalk thickening . Antinuclear antibodies and anti-neutrophil cytoplasm antibodies were negative. Salivary gland emission computed tomography dynamic imaging showed impaired function in both submandibular glands. Pancreatic enhanced magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography showed a swollen pancreatic tail and a local stricture of the pancreatic duct section of the common bile duct  twice daily for asthma. Rivaroxaban  was orally administered for pulmonary embolism. Desmopressin acetate tablets (Minirin®) were orally administered at a dose of 0.15 mg per day for central diabetes insipidus. We administered 30 and 50 mg per day of prednisone and iguratimod, respectively, for the IgG4-RD. The patient’s clinical condition improved significantly post-therapy, and the filling defects in the right pulmonary artery disappeared. Prednisone was gradually reduced. The serum levels of eosinophils, total IgE, and IgG4 decreased gradually.One year after his discharge from our hospital, the left pulmonary nodule was enlarged. The positron emission tomography-CT showed a nodule (2.3 cm × 1.5 cm) in the left inferior lobe with hypermetabolism  Hypereosinophilia is strongly associated with thrombosis , 16. We Malignant transformation is not observed in KD. However, malignancies and IgG4-RD may be strongly associated. IgG4-RD increases the risk of cancer , 18, 19.Understanding the potential common pathogenesis of IgG4-RD and KD may provide a certain basis for their co-occurrence. The pathogenesis of both IgG4-RD and KD may be associated with an unknown chronic allergen stimulation that can cause a series of abnormal immune reactions , 5. AntiReviewing the case, we find that the patient had a long course of disease, and the manifestations of the affected organs did not occur simultaneously. In addition, the patient first visited stomatology only with submaxillary mass and without any other clinical manifestations. This could have caused the specialist to neglect examination for systemic diseases, especially the immunohistochemical tests for IgG and IgG4 in the pathological tissue. Patients with KD are prone to relapse; the recurrence rate is 60 − 80% . ConfirmWe report the various manifestations of a patient with concurrence of KD and IgG4-RD, an unusual combination of two rare diseases. This report highlights the importance of close monitoring for the development of malignancies in IgG4-RD.


A flexural fatigue life equation was then constructed considering various failure probabilities . The results show that POM fiber had no discernible impact on the static load strength of airport pavement concrete, and the difference between PFAPC and OPC in terms of static load strength was less than 5%. POM fiber can substantially increase the flexural fatigue deformation capacity of airport pavement concrete by almost 100%, but POM fiber had a different degree of detrimental impact on the fatigue life of airport pavement concrete compared to OPC, with a maximum decrease of 85%. The fatigue lives of OPC and PFAPC adhered to the two-parameter Weibull distribution, the single- and double-log fatigue equations considering various failure probabilities had a high fitting degree based on the two-parameter Weibull distribution, and their R2 was essentially over 0.90. The ultimate fatigue strength of PFAPC was roughly 4% lower than that of OPC. This study on the flexural fatigue properties of POM fiber airport pavement concrete has apparent research value for the extension of POM fiber to the construction of long-life airport pavements.Polyoxymethylene (POM) fiber is a new polymer fiber with the potential to improve the performance of airport pavement concrete. The effect of POM fiber on the flexural fatigue properties of concrete is an important issue in its application for airport pavement concrete. In this study, four-point flexural fatigue experiments were conducted using ordinary performance concrete (OPC) and POM fiber airport pavement concrete (PFAPC) with fiber volume contents of 0.6% and 1.2%, at four stress levels, to examine the flexural fatigue characteristics of these materials. A two-parameter Weibull distribution test of flexural fatigue life was performed, after examining the change in flexural fatigue deformation using the cycle ratio ( Cement concrete is often used for airport pavement structures. Presently, aircraft are carrying increasingly heavy loads, and takeoffs and landings happen more frequently, so the load on airport pavement structures is becoming increasingly severe; cracking, angle loss, and plate fractures frequently occur during the course of operations . As suchS–N) curve could not be created. On the basis of the four-point flexural testing of trabecular beams, Lv -lnN curves of OPC and PFAPC were developed with varying fiber contents under various stress levels, as shown in According to the information in p)] and lnN, and the correlation coefficient R2 was greater than 0.9. The fatigue life could be described by a two-parameter Weibull distribution. iN is the fatigue life associated with serial number i; the coefficient b and the life characteristic aN were substituted into the preceding formula. The Kolmogorov–Smirnov (K–S) method was used to test the degree of fatigue life fit, to confirm the utility of the two-parameter Weibull distribution for assessing the fatigue life distribution of OPC and PFAPC. Small sample sizes (less than 20) are better-suited for the K–S test . Equation was five and the significance level was 0.05, the critical value cD was 0.563, the observed statistical values iD of each group were all less than cD, and the K–S test results was accepted, which further verified that the fatigue life distribution of OPC and PFAPC followed the two-parameter Weibull distribution. The significance level was less than 5%.By checking the K–S critical value table, when the sample size S-lgN) and double-logarithm (lgS-lgN) fatigue equations for concrete are frequently used by engineers to match fatigue performance curves. The single-logarithm fatigue equation is as follows [The single-logarithm ( follows :(7)S=A−BThe fatigue equation has two boundary conditions :(8)S=1(NS < 0.50). The double-log fatigue equation [S→0:The second boundary condition of the single-log fatigue equation cannot be satisfied, preventing the determination of the fatigue properties of concrete at low stress levels . The fatigue lives of OPC and PFAPC both followed a two-parameter Weibull distribution, according to the analysis in fN under various failure probabilities F:To meet the safety performance requirements under cyclic loading in practical engineering, the b and aN obtained in fN  of OPC and PFAPC were calculated with given failure probability F, as shown in The coefficients A, B, lga, and b of the single- and double-log fatigue equations, which correspond to various failure probabilities F.The data in R2 between OPC and PFAPC rapidly declined as the failure probability increased. In the single-logarithmic form of fitting, the correlation of other groups under different failure probabilities was over 0.90, and the correlation of the PFAPC group was above 0.97, with the exception of a slightly lower correlation in OPC when the failure probability was 0.40–0.50. With the exception of a marginally lower correlation in OPC when the failure probability was 0.20–0.50, the correlations of all other groups in the double-log fitting were over 0.90, whereas those of the PFAPC group were above 0.96. This showed that when the failure probability F is considered, the equivalent fatigue life fN of the PFAPC obeyed the two-parameter Weibull distribution with high accuracy. Additionally, the corresponding linear relationship between the single-log fatigue equation and the double-log fatigue equation was essentially established, with the degree of fit for the single-log fatigue equation being slightly higher than that of the double-log equation. This is in line with the results of the fitting correlations between the average fatigue life corresponding to the single- and double-log fatigue equations.F had little impact on regression coefficients B and b, and can be ignored, similar to the majority of the fatigue test results for fiber-reinforced concrete. The single- and double-logarithm fatigue equations of airport pavement concrete, considering failure probability F, can be determined by using the average value of B and b as the general result, as shown below:Failure probability S-N curves with high reference values. The first is the P-S-N curve, which corresponds to a survival rate of 50%, or a failure probability of 50%; the maximum fatigue strength of a material can be determined through this curve. The second is the corresponding survival-rate P-S-N curve; P is 95%, which means that F is 0.05 in terms of failure probability. The ultimate strength of the material under conditional fatigue can be determined by this curve, and this value can serve as a general guide for structural design [P-S-N curves for the two survival rates.These equations serve as a guide for forecasting the fatigue life of PFAPC with various failure probabilities under various stress levels, when the above formulae are combined with the regression coefficients under various failure probabilities as shown in l design ,35. Figu6 cycles of loading. The ultimate fatigue strength of material generally refers to the maximum fatigue stress that the material can withstand under a certain number of cycles, and is usually expressed in the form of static flexural strength percentage in practical application [6 fatigue cycles. The OPC and PFAPC ultimate fatigue strength (upper limit of stress level) and conditional ultimate fatigue strength corresponding to a 2 × 106 fatigue life under two survival rates was calculated using According to a previous study , a concrlication ,7,24. Rerf , 0.66 rf, and 0.65 rf, respectively, equating to a 2 × 106 fatigue life. The conditional ultimate fatigue strengths of OPC, PFAPC-0.6, and PFAPC-1.2 corresponding to a 2 × 106 fatigue life were calculated as 0.65 rf, 0.64 rf, and 0.63 rf, respectively, when considering a survival rate of 95%. The average fatigue life of the material in the fatigue test was indicated to be larger than 2 × 106 times when the loading stress amplitude was less than or equal to the ultimate fatigue strength, suggesting no fatigue failure. When the survival rate was 50%, the fatigue strength of concrete with POM fibers at 0.6 and 1.2% volume decreased by 2.9 and 4.4%, respectively; when the survival rate was 95%, the fatigue strength fell by 1.5 and 3.1%, respectively. The addition of POM fiber reduced the flexural fatigue performance of airport pavement concrete to a certain extent.No difference in the ultimate fatigue strength was estimated by using the single-logarithm and double-logarithm form equations, as shown in the calculation results in PFAPC specimens exhibit particular ductile failure traits when subjected to fatigue stress, and a three-stage curve can adequately represent the complete fatigue deformation process.S = 0.80), the maximum midspan deflection of PFAPC-1.2 increased by 37.9%, and the maximum tensile strain increased by 89.2%; at a low stress level (S = 0.65), its maximum midspan deflection increased by 101.2%, and the maximum tensile strain increased by 36.5%.POM fiber can somewhat increase the deformation capacity of airport pavement concrete under flexural fatigue loading at different stress levels. The major improvement was observed in PFAPC-1.2. At a high stress level (S = 0.65), compared with OPC, the fatigue lives of PFAPC-0.6 and PFAPC-1.2 decreased by 23.8% and 52.1%, respectively; at a higher stress level (S = 0.75), their fatigue lives decreased by 83.4% and 85.1% respectively. The fatigue life of PFAPC-1.2 was shorter than PFAPC-0.6, except at the 0.80 stress level.PFAPC has a substantially shorter fatigue life than OPC, and starts to decline noticeably at increasing stress levels. At a low stress level (R2 was generally above 0.90, and these conclusions were further verified by K–S testing. The single-logarithm fatigue equation had a marginally higher fit than the double-logarithm fatigue equation, both of which were developed using two-parameter Weibull distributions considering various failure probabilities. The ultimate fatigue strength of airport pavement concrete is marginally decreased by the addition of POM fiber.The fatigue life of OC and PFAPC well obeyed the two-parameter Weibull distribution, the fitting correlation coefficient The conclusion shows that POM fibers have different degrees of negative effects on the fatigue life of airport pavement concrete. This is different from the results from other studies of polymer-fiber-reinforced concrete. These findings were obtained under the premise of ensuring the validity of the test results. It is hoped that this conclusion will be taken seriously by more colleagues and more research will be conducted to clarify why these negative effects occur, and how they should be addressed.


MET use was significantly associated with a reduced degree of knee pain after being adjusted for the above covariates . There was a significantly accumulative effect of MET use on the reduced risk of TKA. Conclusion: MET can be a potential therapeutic option for OA. Further clinical trials are needed to determine if MET can reduce the risk of TKA and the severity of knee pain in metabolic-associated OA patients.Objectives: We aimed to examine whether metformin (MET) use is associated with a reduced risk of total knee arthroplasty (TKA) and low severity of knee pain in patients with knee osteoarthritis (OA) and diabetes and/or obesity. Methods: Participants diagnosed with knee OA and diabetes and/or obesity from June 2000 to July 2019 were selected from the information system of a local hospital. Regular MET users were defined as those with recorded prescriptions of MET or self-reported regular MET use for at least 6 months. TKA information was extracted from patients’ surgical records. Knee pain was assessed using the numeric rating scale. Log-binomial regression, linear regression, and propensity score weighting (PSW) were performed for statistical analyses. Results: A total of 862 participants were included in the analyses. After excluding missing data, there were 346 MET non-users and 362 MET users. MET use was significantly associated with a reduced risk of TKA (prevalence ratio: 0.26, 95% CI: 0.15 to 0.45,  Osteoarthritis (OA) is a chronic musculoskeletal disorder and one of the major causes of disability among the elderly. In China, the prevalence of symptomatic OA is 8.1% and is expected to increase due to accelerating aging ,3. In thOA is a heterogeneous disease caused by multiple factors . StudiesMetformin (MET) is a first-line drug for type 2 diabetes . In addiSome observational studies have demonstrated a protective effect of MET against OA. A population-based cohort study showed that the combination of MET and COX-2 inhibitors can reduce the incidence of TKA in patients with OA and type 2 diabetes . AnotherMET may play a potential therapeutic role in targeting MetS-OA by regulating inflammatory and metabolic factors. However, clinical studies evaluating the effect of MET on MetS-OA are rare and inconclusive. Therefore, the purpose of this study was to examine whether MET use is associated with a reduced risk of TKA and decreased knee pain severity in knee OA patients with diabetes and/or obesity.https://www.yiducloud.com.cn/) (accessed on 12 December 2019). The study was approved by the institutional review board and ethics committee at a local hospital, and informed consent was waived.This was a retrospective, cohort study using the routinely recorded information from a local hospital. Inclusion criteria were as follows: participants aged more than 18 years old; hospitalized in the local hospital from 10 June 2000 to 15 July 2019; discharge diagnosis was “knee osteoarthritis” or “knee osteoarthropathy” or “degeneration of the knee joint” combined with “diabetes” and/or “obesity”. Patients with inflammatory arthritis including gout, reactive arthritis, rheumatoid arthritis, psoriatic arthritis, and systemic lupus erythematosus were excluded . We collParticipants were classified as regular MET users if they were recorded using MET following the doctor’s advice or self-reported regular MET use in past medical history and had been using MET for at least 6 months. Non-users of MET were defined as participants who were not recorded using MET at physician orders or did not ever report the use of MET or whose MET was first administered after TKA or who used MET for less than 6 months. Additionally, we further calculated the duration of MET use based on the sum of each duration of MET use and classified it as short-term and long-term MET use, using the median (2100 days) as the cutoff point. Patients who recorded only one time for using MET or did not record the time of use in their medical history were excluded from the classification of the duration of MET. In addition, the total MET dose was calculated based on the sum of each MET single dose multiplied by the duration of each MET use. We further classified the total MET dose as low dose and high dose, using the median (1048 g) as the cutoff point.In this scheme, TKA was regarded as the end point of OA. “Knee arthroplasty” was included in the surgical name screened from the database as the occurrence of TKA. Uni-compartmental knee arthroplasty (UKA) was excluded.Knee pain was assessed using the numeric rating scale (NRS) ranging from 0 to 10 . The degThe propensity score (PS) combining the covariates including age, sex, body mass index (BMI), insurance status, and the use of celecoxib, etoricoxib, and tramadol was weighted using the inverse probability of treatment weighting (IPTW) method to balance the covariates between MET user and non-user groups as well as the group using MET more than one year and the group using MET less than one year . SpecifiA post hoc power calculation showed that we had more than 80% statistical power to detect a correlation between MET prescription and TKA risk, with an alpha error of 0.05 and two-sided significance.p value < 0.05 (double-tailed) or 95% confidence interval (CI) for β not including 0 (linear regression) or 95% CI for PR not including 1  were considered statistically significant.Statistical analyses were conducted using Stata/MP 14.0 for Windows  and R software . The characteristics of the participants are shown in p < 0.001, p < 0.001, respectively). MET use was significantly associated with a lower degree of knee pain before and after adjustment for the above covariates .Before IPTW, 5% of the patients in the MET-user group performed TKA, while 19% of the patients performed TKA in the MET-non-user group. The MET users had an average knee pain score of 1.6, while MET non-users had an average knee pain score of 2.1. MET use was significantly associated with a decreased risk of TKA before and after adjustment for age, gender, BMI, insurance status, and the use of celecoxib, etoricoxib, and tramadol (p < 0.001). Moreover, MET use was still significantly associated with a lower degree of knee pain (p = 0.031).After IPTW, 6% of the patients in the MET-user group performed TKA, while 21% of the patients performed TKA in the MET-non-user group. The average knee pain scores were the same as the ones before IPTW. MET use was still significantly associated with a reduced risk of TKA . Additionally, there were significant differences in TKA risk between short-term MET use and long-term MET use. After IPTW, the findings were largely similar. Taken together, there was a significant accumulative effect of MET use on the reduced risk of TKA   .p = 0.020 and 0.042, respectively), compared with MET non-use. Although long-term MET use was not significantly associated with knee pain, compared with MET non-use, there was a trend of an association between long-term MET use and the degree of knee pain . After IPTW, the results were largely similar. Taken together, the increased duration of MET use was significantly associated with the reduced severity of knee pain before but not after adjusting for covariates   .p for trend <0.001). After IPTW, the findings were largely similar. Taken together, there was a significant dose-dependent effect of MET use on the reduced risk of TKA . After IPTW, the results were largely similar. Taken together, there was no significant dose-dependent effect of MET on the reduced severity of knee pain   .Using the data collected from the information system of a local hospital, the current study found that MET use was significantly associated with a decreased TKA rate and knee pain severity, compared with MET non-use, among patients with OA combined with diabetes and/or obesity. Meanwhile, increased duration of MET use was significantly associated with a reduced risk of TKA, suggesting a potential accumulative effect of MET use on the reduced risk of TKA. An increased total MET dose was significantly associated with a reduced risk of TKA, indicating that there may be a potential dose-dependent effect of MET use on the risk of TKA.Recent studies found that, besides the hypoglycemic effect, MET may attenuate OA through alleviating inflammation, protecting cartilages, and reducing pain ,22. NeveIn terms of knee pain, considering the mild knee pain in the OAI cohort, Wang et al. did not find a significant association between MET use and change in WOMAC pain over four years . CollectThe biological mechanisms linking MET to OA are largely unclear. Previous studies revealed that MET could modulate and weaken pro-inflammatory responses induced by lipopolysaccharide (LPS) in monocytes and macrophages . These aThe current study may have some clinical implications. At present, there is still a lack of effective drugs for the treatment of OA. Clinically, as the primary drugs for controlling OA symptoms, the long-term use of NSAIDs will not reduce or even increase the risk of TKA ,30,31. MRegarding the association of MET and the progression of knee OA in patients without diabetes mellitus, the current study did not have sufficient samples to assess this association (data not shown). A previous study investigating the association between MET use and disease progression in obese people with knee OA found that MET use was significantly associated with lower rates of medial cartilage volume loss, indicating that MET may have protective effects on knee OA progression in people without diabetes mellitus . MoreoveThe current study is the first to demonstrate an association between MET use and a lower risk TKA and lower severity of knee pain in osteoarthritic patients combined with diabetes and/or obesity. However, this study has several potential limitations. First, subject to the hospital information system, this study used a cross-sectional design. Second, patients with a prescription of MET had a higher rate of COX-2 inhibitors usage, a lower rate of tramadol usage, and a lower degree of knee pain before PSW. Therefore, while PSW was used to control potential confounding effects, residual confounding factors still could have affected the findings of this study. Third, the current study was conducted among OA patients with diabetes and/or obesity. Hence, these findings may not be generalizable to all OA patients. Fourth, the current study lacks relative data on the side effects of MET; it should be considered that some patients may experience side effects such as gastrointestinal side effects  and B12 deficiency. Fifth, due to a lack of radiographic OA data, we could not examine the association between MET use and the progression of radiographic OA.MET can be a potential therapeutic option for OA. Further clinical trials are needed to determine if MET can reduce the risk of TKA and the severity of knee pain in metabolic-associated OA patients.


Corrosion of steel bars is of great significance for safety and service life of reinforced concrete structures. This work develops a prediction method for steel corrosion mass loss rate before the crack of concrete structure based on a spiral distributed fiber optic sensor. Reinforced concrete sample instrumented with a spiral distributed fiber optic sensor were prepared. The mathematic relationship between the corrosion mass loss rate of steel bar and the spiral distributed strain is theoretically derived. Meanwhile, numerical analysis by MATLAB shows that these parameters such as the protective layer thickness, corrosion mass loss rate, bar diameter, corrosion expansion coefficient have a remarkable influence on spiral distributed strain. Additionally, electrical accelerated corrosion experiment was performed on the reinforced concrete specimens. The helix strain along the distributed sensor was used to evaluate the corrosion mass loss of steel bar. Further, the influencing factors on the corrosion sensitivity are illustrated here and the corrosion mass loss rate before concrete crack is also quantified. This research provides insights into the corrosion deteriorate mechanism. Many engineering structures are made of reinforced concrete. Steel bars corrosion has been a main challenge for durability of reinforced concrete structures, which has attracted a wide attention of scholars both at home and abroad ,2,3. SteDespite of the exciting advancement, the FBG and LPFG sensor only measures monitoring corrosion at a single spot installing a sensor, and the degradation of a corrosion sensor is quick and irreversible ,20,22,23Thus, this work has two main objectives: (1) deduces a theoretical mathematic model between the corrosion rate of steel bar and optical fiber strain based on a helix pattern rather than a ring pattern, and (2) attains a practicable model between steel corrosion mass loss rate and spiral distributed strain from a helix distributed sensor. The influencing fac-tors on the corrosion sensitivity are illustrated by numerical analysis with MATLAB. Meanwhile, the mathematical model between steel corrosion rate and the spiral distributed strain is experimentally verified and illustrated. This work ultimately provides a quantitative method of predict the corrosion mass loss rate before the concrete crack occurs.BOTDA technology is based on stimulated Brillouin scattering effect. The Brillouin frequency shift depend on the fiber strain and temperature. When the temperature and strain change, the Brillouin frequency will shift. Thus the temperature and strain can be calculated from the Brillouin frequency shift :(1)vBAccording to elastic mechanics theory, the fiber model can be simplified to a two-dimensional model, due to the corrosion expansion independent on the steel bar length, and concrete material is further assumed to be isotropic ,37.(2)The actual corrosion duration and corrosion velocity depends on the electrical current intensity;(3)It is assumed that the steel bar corrosion expansion is uniform, then the thick wall cylinder elastic mechanics model can be used to describe the corrosion process ,38.Corrosion rate before concrete cracks occur is discussed based on elastic mechanics theory, while the distributed fiber strain is dependent on the crack width after the concrete crack. Therefore, we make the following assumptions:When pristine concrete and steel bar are considered as an integrated object, the corrosion process of reinforcement concrete is divided into three stages, as shown in concrete , R is thAccording literature , the tenPlugging Equation (4) into Equation (3), the thickness of the rust Then the combined diameter of steel bar and the rust before the concrete begin to crack is determined:As shown in Plugging Equation (6) into Equation (9)Plugging Equations (5) and (6) into Equation (10), the mathematical relation between fiber strain and corrosion rate is derived:2OH, and Fe3O4 Fe2O3, the expansion volume of Fe2O3 is identical with that of Fe3O4. The volume of Fe3O4 and Fe2O3 in corrosion product is accounted for 85%, n is approximately from 1.79 to 2.56, typically 2. The elastic modulus of concrete is 35 GPa.The magnitude of corrosion expansion ratio ,42 has bn = 2, Meanwhile, the author analyzed the influence of the steel bar diameter of 5 mm, 10 mm, 16 mm, 20 mm on helix distributed strain  is less than that the specimen with a smaller corrosion expansion coefficient. However, the corrosion expansion coefficient n is difficult to be precisely measured, and the helix fiber strain is consequently unable to be calculated by Equation (11).The influence of corrosion expansion coefficient on the spiral fiber optic strain is shown in To sum up, these parameters such as the protective layer thickness, corrosion mass loss rate, bar diameter, corrosion expansion coefficient has a remarkable influence on the spiral distributed strain.The optical fiber used in the experiment is a tight-jacketed optical cable in 0.9 mm diameter with a high stain transmission efficiency. The mortar cover is produced with ordinary Portland cement, water, fine aggregate and water reducing agent  in a weight proportion of 1.0: 0.45: 0.1: 0.03. The cement used is P.O 42.5. There is a 200 mm-long straight round carbon steel bar in 16 mm diameter used. To induce a uniform surface property, the bar surfaces were sandblasted to remove the mill scale in order. Subsequently, a spiral distributed sensing fiber with a 30° helix angle was wound with an 8.7 cm interval around the steel bar. Meanwhile, Mortar is cast to a cylindrical mould and a 10 mm-thickness mortar layer is covered on the steel bar. Eventually, a spiral distributed sensing fiber with a 60° helical angle was wound with a 6.5 cm pitch and embedded into concrete with a 67 mm and 142 mm concrete cover, demolded after 24 h, and cured for 28 days. The specimens are named as 2-150# and 2-300#, respectively. To the end, the concrete end surfaces were sealed using silica gel to prevent from the outflow of corrosion products.After 28-days of concrete curing, the concrete specimens were subjected to electrochemically accelerated corrosion to obtain a continual corrosion loss. Before corrosion test, the fabricated concrete samples were immersed in 5% sodium chloride solution for 48 h. The content of admixed chloride in this study far exceeded the critical chloride threshold. Hence depassivation was warranted for the adopted polished surface condition. A copper wire was subsequently soldered at each end of steel bar. Meanwhile, the steel bar and a copper beam were, respectively, connected to the positive and negative electrodes of the power supply. The initial designed corrosion current is 0.1 A constant current. The calculation of steel corrosion rate follows Faraday’s law. Both ends of the fiber jumper are connected to the Pump and Probe end of BOTDA. The FBG temperature sensor is connected to SM130 Demodulation System and placed in the U-shaped slot in a free state. The experimental setup is detailed in For the specimen with a 67 mm protective layer (mortar layer), the electrical current generated more heat in the corrosion process. FBG sensor  was used to measure the temperature around the steel bar. It is observed from The strain-time curves before and after temperature compensation for specimens 2-150# and 2-300# are shown as (1)Reinforced concrete specimen with a 67 mm concrete coverThe strain-time curves are shown in ariation . Thus, i 0–20 um , which cP value of regression equation less than 0.05 illustrates that the linear arrogation equation developed in this work is credible.Meanwhile, the raw and actual strains in the distributed sensor monotonically increase over time and corrosion mass loss rate. Each curve shows four stages, which the I, II, III stages are consistent with the degradation of reinforcement concrete in iterature,32. Poss(2)Reinforced concrete specimen with a 142 mm concrete coverMeanwhile, the distributed expansive strain at the initial stage of specimen corrosion (about 0~40 h) after temperature compensation fail to be generated. The called corrosion rate threshold is about 1.34%, and cracking occurs at 160 h close to the observed cracking time of 155 h. The error is approximately 0.14%. Additionally, the distributed strain depends on a rising ambient temperature induced by the electro-accelerated corrosion.P values of regression equation are less than 0.05, thus the linear equation is credible.To the end, the raw and actual strains from the distributed sensor monotonically increase over time and corrosion mass loss rate. Each curve shows three stages, being consistent with the degradation of reinforcement concrete. Regression analysis is performed to determine the equation of stages 2, 3 and 4. Before reinforcement concrete cracks, the slope of the fitting equation between the distributed strain and corrosion mass loss rate from the distributed sensor on the steel bar and mortar layer is 121 To sum up, each curve can be divided into four stages , which mirrors applied electrical current fluctuations and the degradation of concrete structure. A comparative analysis of specimens with protective layer thicknesses of 67 mm and 142 mm and an effective length of 200 mm shows that the corrosion rate thresholds in the first stages are related to the protective layer thickness of concrete structures. Furthermore, the crack corrosion rates observed the crack from the distributed strain are basically consistent with the actual corrosion rate optically observing crack.Moreover, the corrosion sensitivity (stage II) before cracking of 2-150# and 2-300# concrete specimens is shown in To predict the corrosion rate of steel bar before the concrete crack, the authors put forward a prediction method using a spiral distributed optical fiber sensor. The main conclusions are as follows:(1) The mathematical model between steel corrosion rate and optical fiber is illustrated and the influencing factors of fiber strain are discussed here. The numerical analysis shows that the helical strain increases with the decrease of the thickness of concrete cover, declines with the increasing thickness of the porous zone, and grows with the corrosion expansion ratio.(2) In the process that reinforced concrete is corroded and broken, the strain measured from the spiral distributed optical fiber sensor is divided into four stages: (i) no strain stage; (ii) slow growth stage, (iii) abrupt change stage; and (iv) stabilized stage. These four stages are consistent with the concrete structure degradation: the corrosion products filling the porous region, the corrosion products accumulating until cracks generate, cracks propagating, and the equilibrium between corrosion products generation and outflow from cracks. (3) In the electro-accelerated corrosion test, a temperature fluctuation should be measured to eliminate the temperature error. The corrosion rate thresholds in the first stages depends on the protective layer thickness. In addition, the corrosive sensitivity of the proposed distributed sensor here is basically in a good agreement with a 92.8


This cross-sectional study examines prescribed and filled antibiotics for outpatient COVID-19 treatment among children, adolescents, and adults with commercial insurance. The Harvard Institutional Review Board deemed this cross-sectional study exempt from review and waived the informed consent requirement because deidentified data were used. We followed the STROBE reporting guideline.We identified outpatient visits with an 1 we identified outpatient visits by individuals with both medical and pharmacy coverage and their association with antibiotic fills within 7 days before or after these visits , urgent care, or other .Consistent with prior research,We included 1 293 303 adult visits and 177 057 children and adolescent visits. Antibiotic receipt during COVID-19–related visits increased with age: 4% in 0-to-5-year to 16% in 45-to-64-year age groups . COVID-1COVID-19–related visits in children and adolescents vs adults occurred predominantly in physician offices (66% vs 51%), followed by EDs (12% vs 18%) and practice-based telemedicine (11% vs 17%). Antibiotic receipt varied by site of care, with highest rates at practice-based telemedicine and ED visits for all groups except 0 to 5 years . Among cAmong children younger than 6 years, the most common antibiotic was amoxicillin (37%) followed by azithromycin (36%). In those aged 6 to 17 years and adults, azithromycin (68% and 70%) was more commonly received than amoxicillin (15% and 4%).Antibiotic receipt at COVID-19–related visits was substantially lower for children and adolescents than adults and varied by region and site of care. Increased prescriptions in adults may be associated with a higher prevalence of comorbidities and higher risks of adverse outcomes.1 Azithromycin might be selected for its potential anti-inflammatory and antiviral properties, especially before more data were available.4 Amoxicillin use among the youngest group suggests concerns about associated (but undiagnosed) bacterial infection such as otitis media or pneumonia.The findings that, among both adults and those aged 6 to 17 years, antibiotic receipt was highest at ED and practice-based telemedicine visits and that azithromycin was the most common were consistent with prior results.5 The ICD-10 code U07.1 appears highly specific but not as sensitive for COVID-19–related visits.6 Claims data did not include prescribed but not filled antibiotics or antibiotics purchased without insurance. We also did not examine how severity of illness or presence of comorbidities was associated with antibiotic use. Understanding these prescribing practices will inform efforts to improve antibiotic stewardship.Study limitations included the lack of data on Medicaid-covered encounters or visits by uninsured individuals. Additionally, data were collected when pediatric visits and antibiotic use for non–COVID-19 ARTI-related visits were lower than usual.


MET amplification and MET overexpression). We analyzed 89 longitudinal plasma samples from MET-dysregulated advanced-stage NSCLC patients treated with MET inhibitors by the method of mass spectrometry. The results showed that the peripheral plasma proteomic characteristics were associated with the outcomes of patients treated with MET inhibitors. Through biomarker selection, we found a four plasma protein signature  could predict the response and progression-free survival of patients treated with MET inhibitors with high accuracy. This study highlighted the clinical utilization of plasma biomarkers to scream patients to receive MET inhibitors.Targeted therapy has revolutionized the treatment of non-small cell lung cancer (NSCLC) and MET inhibition is a promising therapy for MET-dysregulated NSCLC. However, due to the lack of effective biomarkers, the clinical efficacy is unsatisfactory. This study aims to investigate the clinical utility of plasma proteomics-derived biomarkers for MET-dysregulated NSCLC (including MET amplification and MET overexpression) treated with MET inhibitors. Thirty-three MET-dysregulated NSCLC patients with longitudinal 89 plasma samples were included. We classified patients into the PD group and non-PD group based on clinical response. The baseline proteomic profiles of patients in the PD group were distinct from those in the non-PD group. Through protein screening, we found that a four-protein signature  could predict the efficacy of patients treated with MET inhibitors, with an area under the curve (AUC) of 0.93, better than conventional fluorescence in situ hybridization (FISH) or immunohistochemistry (IHC) tests. In addition, combining the four-protein signature with FISH or IHC test could also reach higher predictive performance. Further, the combined signature could predict progression-free survival for MET-dysregulated NSCLC (p < 0.001). We also validated the performance of the four-protein signature in another cohort of plasma using an enzyme-linked immunosorbent assay. In conclusion, the four plasma protein signature  might play a substitutable or complementary role to conventional MET FISH or IHC tests. This exploration will help select patients who may benefit from MET inhibitors.MET inhibitors have shown promising efficacy for MET-dysregulated non-small cell lung cancer (NSCLC). However, quite a few patients cannot benefit from it due to the lack of powerful biomarkers. This study aims to explore the potential role of plasma proteomics-derived biomarkers for patients treated with MET inhibitors using mass spectrometry. We analyzed the plasma proteomics from patients with MET dysregulation (including  MET proto-oncogene has been known to play an important role in promoting tumor cell proliferation, tumor invasion, and metastasis in non-small cell lung cancer (NSCLC) either as a primary oncogenic driver or as a co-driver in the context of acquired resistance to tyrosine kinase inhibitors (TKIs) [MET amplifications, protein overexpression, gene mutations, and fusions [MET amplification of NSCLC is 1–5% and 5–20% for MET de novo and acquired amplification, respectively [MET amplification or MET protein overexpression with an objective response rate of approximately 67% and 68% (IHC3+), respectively [The s (TKIs) ,2,3. Act fusions . The preectively ,7. Previectively ,10. MET amplification for NSCLC patients. It can distinguish MET focal amplification from MET polysomy by calculating both the copies of MET per cell and the ratio of MET to chromosome (MET/CEP7) [MET copy number and MET/CEP7 threshold to select eligible patients to receive MET inhibitors. Many FISH-selected patients cannot benefit from MET inhibitors [MET amplification is poor [Fluorescence in situ hybridization (FISH) is a standard method to detect ET/CEP7) ,12. Howehibitors ,13. MET hibitors ,9. Howev is poor ,15. ThusMass spectrometry (MS)-based proteomics is a high-through and unbiased method for characterizing oncogenic mechanisms and identifying potential prognostic and predictive biomarker . It can Herein, we conducted a MS-based, data-independent acquisition (DIA) quantitative proteomic approach to explore the blood-based proteomic profiles to determine predictive biomarkers for MET-dysregulated NSCLC patients treated with MET inhibitors. The selected biomarker candidates were further validated by enzyme-linked immunosorbent assay (ELISA) tests in the validation cohort.MET amplification by FISH with mean gene copy number greater or equal to five, and a MET to centromere of chromosome 7 (MET/CEP7) ratio of 2 or more [Advanced-stage NSCLC patients with MET dysregulation treated with MET inhibitors were enrolled from 1 October 2014, to 10 April 2019, at Guangdong lung cancer institute. MET dysregulation consisted of MET protein overexpression with MET IHC score ≥270 and  or more ,22. TumoPlasma samples were collected in pro-coagulation vacuum tubes using standard venipuncture protocols and were then extracted by centrifugation for 15 min at 2500 rpm. The Plasma samples were stored at −80 °C before use.g for 30 min at 4 °C, the pellets were washed with 500 µL cold acetone three times and dried with a vacuum concentrator . The dried pellets were dissolved in 40 µL 8 M Urea in 500 mM Tris-HCl buffer (pH 8.5) and ultrasonically treated for 10 min. The samples were reduced with 20 mM (2-carboxyethyl) phosphine hydrochloride (TCEP) (500 mM in 100 mM Tris/HCl pH 8.5) at room temperature for 20 min and alkylated with 40 mM IAA at room temperature in the dark for 30 min. The mixtures were diluted with 200 µL 100 mM Tris-HCl buffer (pH 8.5) followed by adding trypsin at a 1:20 ratio for 16 h. The peptides were desalted and re-dissolved with 50 µL Mil-li-Q water with 0.1 vol% formic acids (FA). The indexed Retention Time (iRT) calibration peptides were spiked into the 89 peptide samples for DIA analysis later. The mixed sample without iRT peptides was separated into two samples, one of which was used for High-PH reversed-phase fraction and quality control (QC) of the DIA analysis later, respectively. The QC sample was added with iRT before analysis.All plasma samples were processed by the Agilent 1290 Infinity II liquid chroma-tography system coupled with the Multi Affinity Removal Column, Human-14 to remove abundant proteins. About 10 µL each sample was taken out and mixed. The mixed sample and all the 89 samples were precipitated by trichloroacetic acid (TCA) solution for about 4 h at 4 °C. After centrifuging at 16,000× The mixed peptide sample fractioning was performed on a Chromatographic column  coupled to a Waters XevoTM AC-QUITY UPLC  with an 80 min liquid phase gradient. We collected the first 4 min of liquid as the first fraction, the liquid of the 64–68 min as the last fraction, and discarded the liquid of the last 12 min. We collected the liquid sample every minute during the gradient of 4–64 min. The first fraction was mixed with the last one and the rest were mixed in pairs every 30 fractions. Finally, 31 fractions were obtained and vacuum-centrifuge dried. All 31 fractions were reconstituted in 10 µL Milli-Q water with 0.1 vol% formic acids (FA). IRT peptides were spiked before the data-dependent analysis (DDA).All the peptide samples were separated on an EASY-nLC1200 liquid chromatography system  coupled with a 25 cm × 75 μm home-packed analytical column (1.5 μm ReproSil-Pur 120 C18-AQ particles (Dr. Maisch)). Mobile phases A and B were water and 80% ACN with 0.1 vol% formic acids. Samples were analyzed with a 120 min gradient at a flow rate of 300 nL/min and the concentration of B% was increased from 4 to 10% within 4 min, followed by an increase to 30% at 4–103 min and a further increase to 100% at 103–113 min and kept 100% B for the last 7 min.All the samples were analyzed on Thermo QExctive HF-X . The 31 fraction samples obtained through high-Ph reversed-fraction processing were operated in data-dependent mode which was used for the spectral library generation. All 89 plasma samples were analyzed in data-independent mode and the data was used for bioinformatic analysis later. We add a technical QC every 12 samples.For the DDA runs, the full MS scan was performed with a scan range (m/z) between 300 and 1500 m/z. The MS/MS had a resolution of 60,000. The automatic gain control (AGC) target was 3e6 with a maximum injection time of 50 ms. The HCD dd-MS2 scan selected top 30 intensity peptides and was performed with the following parameters: resolution = 15,000; AGC target = 5e5; maximum injection time = 40 ms, NCE = 30, isolation window = 1.7 m/z.For the DIA analysis, the full MS-SIM had a resolution of 60,000 and a scan range between 350–1200 m/z. The AGC target was 3e6 and the maximum injection time was set to 50 ms. Each full MS was followed by 64 narrow isolation widths which were named DIA windows. The resolution was set to 30,000 and the AGC target was 1e6.Spectral libraries were generated from the acquired data of the 31 fractions using Spectronaut version 14.0 (Biognosys) with the default parameters. MS/MS spectra were matched against the database which was downloaded from human UNIPROT .Human protein ELISA kits were used to detect and quantify plasma levels of specific proteins according to manufacturers’ instructions . A total of 100 μL of plasma sample and standard dilutions were added to the precoated plates, and the plates were incubated at 37 °C for 2 h. After three times washing, 100 μL diluted Biotin-Conjugate was added, and the plates were then incubated at 37 ◦C for 1 h. After washing, 100 μL Streptavidin conjugated Horseradish Peroxidase (HRP) was added and incubated at 37 °C for 1 h. 100 μL of Substrate Solution was added and incubated at 37 °C for 10 min. Finally, we added 50 μL of Stop Solution and detected the OD values at 450 nm using microplate spectrophotometer . The determination of OD values from serial dilutions of the standard samples was used to generate a standard curve of each protein and the relative concentrations of samples were calculated. p-value of 0.05 were used to filter differentially expressed proteins using the limma package in R. Dot plots of Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enriched functional pathways were plotted by ClusterProfiler package in R. Significant proteins were used for protein-protein interaction network analysis and network visualization was performed using Cytoscape (version 3.9.1). The Student’s t-test was used to compare the protein levels in the plasma between the two groups. Fisher’s exact test was used to compare two categorical variables. Receiver operator characteristic curves (ROC) analyses were used to assess the overall performance of a test and to compare the performance of two or more other tests. ROC analyses in this study were conducted in pROC package in R using response outcomes and protein intensity values. The AUC value was calculated by the area under the ROC curve and was used to assess the performance of the predictive models. An AUC value of more than 0.8 was considered good. The Youden index, which integrates sensitivity and specificity information, was used to identify the optimal thresholds. The predictive model was constructed using logistic regression in R software. The probability of response was calculated using four protein intensities as the following formula listed.Data analysis including data imputation, normalization, and principal component analysis (PCA) was performed in R software (version 4.1.2). The missing value was replaced with a median value. Fold-change of 1.5 and p value was used to conduct the ROC analysis for the four-protein signature and the corresponding AUC value was calculated. The cut-off value (p = 0.68) of the predictive model was calculated by the Youden index. The p value of more than 0.68 was considered as the low-risk group in the progression-free survival analyses. The predictive p-value were calculated. The hazard ratio was calculated by Cox proportional hazards regression and was used to estimate the ratio of the hazard rate in the two groups. A hazard ratio of 1 indicated that no difference was detected in survival between the two groups. A hazard ratio of greater than one or less than one indicated that survival was worse or better in one of the groups. In the present study, all tests of significance were two-sided, and p-value < 0.05 was considered statistically significant. Survival analysis was performed using Kaplan–Meier survival plot and log-rank test MET amplification by FISH test (n = 16) and MET overexpression by IHC test (n = 23). Six patients were positive in both MET amplification and MET overexpression. All the patients were treated with MET inhibitors. The clinicopathological characteristics and treatment strategies of the enrolled patients were summarized in EGFR mutations and MET dysregulation, 39.4% were treated with EGFR-TKIs plus MET inhibitors. No confounders were found between the PD and non-PD groups .We performed high-resolution mass spectrometry using a DIA method for the peripheral plasma sample. A total of 1619 proteins were identified from all plasma samples and approximately 1106 unique proteins (range: 914–1296 proteins) were identified in each sample . The patWe compared the relative protein intensities between the PD and non-PD groups at baseline plasma A. The rep = 0.024), GNB1 , ALOX12B , and HSD17B4 , respectively. The four-protein signature showed improved predictive performance with an HR of 12.66, 95%CI , P <0.001, better than FISH  and IHC  methods  in the prediction of PFS in patients who received MET inhibitors A. Based  methods B–D. The  methods B. When fectively E,F.In an attempt to investigate the correlation of four biomarkers with clinical efficacy to MET inhibitors, we also monitored the dynamic change of these four proteins in peripheral plasma A. In nonp = 0.06, We detected the concentration of the four proteins  in a validation cohort of 17 patients using the ELISA kit. The clinical characteristics of the patients in a validation cohort was described in p <0.001. This study highlights that the four-protein signature might play an alternative or complementary role to MET FISH or IHC method.To our knowledge, this is the first study to explore the novel non-invasive predictive biomarkers of the efficacy of MET inhibitors for MET-dysregulated NSCLC patients using MS-based proteomics. We found that the plasma proteomic profiles at baseline were associated with the outcomes of patients treated with MET inhibitors. The combined four-protein signature  in plasma might effectively predict the responses and PFS outcomes of patients who received MET inhibitors, with a high AUC value of 0.930 and an HR of 12.66, MET amplification in the clinic, but no consensus regarding the threshold of MET signals and MET/CEP7 value was defined to date [MET amplification was low, and its correlation with treatment outcomes remained controversial [MET amplification from MET polysomy and the purity of tumor DNA also affected the results [Several methods have been examined to select eligible patients for MET inhibitors, including FISH, next-generation sequence (NGS), droplet digital PCR (ddPCR), and IHC methods ,24,25,26 to date . Besidesoversial ,15. Bothoversial . Other d results . MET amplification or MET overexpression separately. Instead, we screened the differentially expressed protein biomarkers in plasma that participated in the MET signal pathway which were also associated with the treatment outcome. Previous studies have demonstrated that a subset of proteins in plasma can be secreted from or interact with the primary tumor [To overcome the flaws of traditional diagnostic methods discussed above, we proposed a novel MS-based proteomic method to select the predictive biomarker candidates for patients treated with MET inhibitors. Although DNA biomarkers have been used to guide personalized oncology, most of the small-molecule inhibitors target proteins instead of DNA, such as EGFR-TKIs ,31. In try tumor ,33,34. Cry tumor . The posGNB1 gene could cause resistance to tyrosine kinase inhibitors for leukemia [We integrated the downstream proteins as a predictive signature, as the single protein dysregulation may not fully represent the abnormality of a pathway. The biological functions of the four proteins have been reported to be associated with cancer development and progression. Previous studies showed that the MYH9 protein could act as a promoter of tumor stemness that facilitates tumor pathogenesis through the regulation of Wnt-β-catenin-STAT3 signaling, which can further interact with the MET pathway . High exleukemia . ALOX12Bleukemia ,39. HSD1leukemia . Previouleukemia ,42. TogeTo confirm the predictive performance of the four-protein signature, we monitored the dynamic change of circulated plasma-based proteomics, especially focusing on the four biomarker candidates. The results showed that protein intensities were associated with the efficacy of the patient treated with MET inhibitors. MYH9, GNB1, and ALOX12B were negatively associated with the tumor response, which represented biomarkers of poor outcomes, while HSD17B4 was positively associated with the tumor response. We also used the ELISA test to validate the concentration of four proteins in a validation cohort. The results showed a similar tendency with an AUC value of 0.848. The model also showed an encouraging performance in the prediction of PFS despite the small sample size. In addition, the results from ELISA also demonstrated the clinical utilities of the four-protein signature as a convenient, non-invasive tool to screen eligible patients for MET inhibitors as ELISA was readily available in most molecular laboratories. Overall, this study can select those patients that did not benefit from MET inhibitors and give them other treatments , which can improve their survival outcomes.Among the limitation of this study, firstly the sample sizes are relatively small with only 33 patients enrolled in our study, which may cause an overfit in our predictive models. Some results in the validation cohort were not significant may also attribute to the small sample size. It is hard to enroll large-scale patients with thorough clinical characteristics, serial plasma sample collection, and longtime follow-up. However, the dynamic change of the four proteins and the ELISA results can consolidate our findings. Secondly, the sample collections had heterogeneity, with a long period of collection time from 2014 to 2019, which may cause discrepant results in our study. Thirdly, the relationship of the four proteins with primary lung cancer tissue remained unknown. Due to the limited tumor tissue, we cannot perform the IHC test for primary cancer tissue to verify the origins of the four proteins.The peripheral plasma proteomic characteristics were associated with the outcomes of MET-dysregulated patients treated with MET inhibitors. A combination of plasma MYH9, GNB1, ALOX12B, and HSD17B4 proteins could effectively and robustly predict the responses and PFS of patients receiving MET inhibitors, with a substitutable or complementary role to conventional MET FISH or IHC tests. This exploration will help select patients who may benefit from MET inhibitors.