Biogenic hydroxyapatite (BHAp) is a widely used material in the biomedical area due to its similarities with the bone tissue mineral phase. Several works have been spotlighted on the thermal behavior of bone. However, little research has focused on determining the influence of calcination temperature in the physicochemical and bioactive properties of BHAp. In this work, a study of the physicochemical properties’ changes and bioactive response of BHAp produced from porcine femur bones using calcination temperatures between 900 to 1200 °C was conducted. The samples’ structural, morphological, and compositional changes were determined using XRD, SEM, and FTIR techniques. XRD results identified three temperature ranges, in which there are structural changes in BHAp samples and the presence of additional phases. Moreover, FTIR results corroborated that B-type substitution is promoted by increasing the heat treatment temperature. Likewise, samples were immersed in a simulated biological fluid (SBF), following the methodology described by Kokubo and using ISO 23317:2014 standard, for 3 and 7 days. FTIR and SEM results determined that the highest reaction velocity was reached for samples above 1000 °C, due to intensity increasing of phosphate and carbonate bands and bone-like apatite morphologies, compared to other temperatures evaluated. Moreover, HAp exhibits bioactive behavior, biocompatibility, non-toxicity, and osteoconductive properties, necessary for healthcare applications2. HAp is usually used in its stoichiometric form (SHAp: Ca10(PO4)6(OH)2 and Ca/P = 1.67); nevertheless, trying to resemble its natural composition and inspired by it, its non-stoichiometric form can also be used, and commonly called BHAp3.During the last decades, the bioceramics field has generated particular interest due to the increasing demand to develop materials for dental and orthopedic applications. In this context, the hydroxyapatite (HAp) is one of the most widely used bioceramics materials in treating different diseases related to the musculoskeletal system because its composition is very similar to the mineral component of hard connective tissue10−x(PO4)6−y(OH)2−(y+z)4, where x, y, and z correspond to the different cations such as Na+, Mg2+, and Sr2+ and anions like SiO2− and CO32−, which can occupy calcium, phosphate or hydroxyl ions position in the lattice6. Any ion substitutions can modify the physical–chemical, biochemical, and physiological properties of the HAp and are feasible due to the HAp lattice flexibility and its structural stability7. According to Siddiqui et al.8, the SiO2−, Mg2+, and CO32− substitutions can enhance the rate of bone growth, bone remodeling and present a better resorption rate, respectively.The BHAp formula can be represented by CaCO32− substitutions are common in the natural bone, which can replace either hydroxyl  or phosphate 8. Likewise, it has been observed that the B-type substitution is related to a decrease in the a-axis and an increase in the c-axis in the HAp lattice. Besides, Siddiqui et al.8 report that the formula is modified in this way Ca10−x(PO4)6−x(CO3)x(OH)2−x, where 0 < x < 2 for this type of substitution. It is believed that when BHAp is implanted, the native tissue growth toward the implant is stimulated, establishing a physical–chemical bond with the adjacent tissue. This behavior can improve its application in dental, maxillofacial, and implants devices11.The 15. Each treatment promotes differences in BHAp properties like the degree of crystallinity, Ca/P ratio related to the solubility, ionic substitution, traces of impurities, and particle sizes or shapes, which impact the biological response16. The thermal process is usually involved during BHAp extraction from bones; hence, the temperature plays an important role in eliminating the organic and hazardous biological remnants and generating HAp lattice transformations.Animal bones  are among the most common sources to prepare BHAp, using calcination or a combination of chemical and thermal treatments17 describe that, depending on the heating rate, some of the calcium oxide (CaO), tricalcium phosphates (TCP’s), and tetracalcium phosphates (TTCP) thermal phases can be favored or not as the heating rate increases20.The HAp lattice transformations, the phases, and properties of the BHAp obtained from animal sources are dependent on the temperature and heating and cooling rates and are also related to the trace minerals present in sources. Ellingham et al.21. This kind of test is usually performed following the protocol established by Kokubo et al.22. Briefly, samples are immersed in an inorganic solution with an ionic concentration close to the human blood plasma, known as simulated body fluid (SBF), and the bone-like apatite layer formation as a function of the time is evaluated23.Furthermore, the features of the BHAp can influence its response in a biological environment since some phases are more soluble than others, and the surface reactivity can enhance or harm its behavior. Bioactivity is the way to evaluate the capability of the biomaterial to form a bone-apatite layer. The velocity of layer formation is related to how bioactive the material is. It can be correlated with the BHAp source extraction, processing temperature, and ion substitution in the HAp lattice24. The bioactivity test was performed following Kokubo’s methodology and using ISO 23317: 2014 standard25. The structural and microstructural changes of the BHAp samples were followed using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) results.Although the bioactive behavior of stoichiometric HAp and that of BHAp has been studied in different works, few studies have been found that present the evaluation of samples’ bioactive behavior, obtained from porcine bone as a function of the calcination temperature. Thus, this work aims to study the temperature treatment effect (from 900 to 1200 °C) on the BHAp samples in the bioactive response24. Briefly, the porcine bones were firstly hydrothermally treated to remove soft tissue and lipids. The samples were then exposed to microwave radiation at 700 W of power and rinsed using a ratio of 1:2 crushed bones/oxalic acid commercial-grade  to soften the peptides bonds. Later, bones were ground in a gravitational miller until the powder achieved particle sizes lower than 38 μm. The miller conditions used for this method were ball powder ratios 10:1 at 100 rpm. Finally, the resulting powders were subjected to heat treatment between 900 and 1200 °C, at a 5 °C/min heating rate and inertial cooling. The temperature was kept for 24 h to promote the HAp phase formation.The BHAp powders were obtained according to the method reported elsewhereα radiation (λ = 1.5406 Å) operating at 30 kV and 20 mA. Diffractograms were taken from 10° to 70° in a 2θ scale and using a resolution of 0.02°. The structural changes, the phase fraction, and the Ca/P ratio in each sample after thermal treatments were determined using Rietveld analysis of the XRD patterns by GSAS. The Ca/P ratio was calculated using Eq.  phase (PDF # 47-1743) was found at 29.40° in 2θ28. In samples thermally treated between 1000 and 1050 °C, a small contribution at 37.48° was found associated with the calcium oxide (CaO) phase (PDF # 37-1497), in addition to the calcite peak29. Finally, the samples treated at temperatures higher than 1100 °C present α-TCP (PDF # 29-0359) and β-TCP (PDF # 09-0169) as additional phases31 . The weight percentages of the phases found in the samples, the changes in the volume of the HAp cell, and the Ca/P ratio calculated using the atoms’ occupancies in the cell obtained by Rietveld refinement through Eq. , 462 cm−1 (υ2), 1021 and 1087 cm−1 (υ3), 561 and 598 cm−1 (υ4)35. The bands at 1044 and 1415 cm−1 were also identified, corresponding to the incorporation of CO32− in the PO43− sites in the HAp cell38. This change is typical of the B-type substitution in the lattice. Particularly, the shoulder at 1044 cm−1 is not observed in the samples with treatments of 900 and 950 °C, which may be associated with a lower B-type substitution in the HAp cell for these calcination temperatures. This behavior will be reviewed in the discussion section39. Additionally, the bands at 629 and 3570 cm−1, corresponding to the hydroxyl group were also identified; these bands are characteristic of the HAp phase40. Finally, Fig. 3 at 1021 cm−1, carbonate at 1415 cm−1, and hydroxyl at 3570 cm−1 as a function of the calcination temperature. In particular, the phosphate group’s intensity for the range of temperatures from 1050 to 1200 °C decreases with respect to the other calcination temperatures19. On the other hand, the functional groups’ intensities of the carbonate and hydroxyl ions do not significantly change in the range of studied temperatures41.Figure 87 cm−1 υ, 561 and−1 the vibrations at 1411 and 1456 cm−1 associated with the B- and A-type substitution were identified. Besides, the contribution at 1415 cm−1 increases its intensity compared to the samples before SBF exposure. Likewise, the shoulder at 1044 cm−1 is not observed in the samples treated at 900 and 950 °C, regardless of the immersion time. In Fig. 3 of the phosphate group shows a slight increase with increasing immersion time in SBF42.Figure 43. Particularly, in the samples treated at 1050 °C after 3 days of immersion, cracks on the material’s surface and agglomerated spheres of micrometer size are observed , whose enthalpy of formation is favorable compared to Mg(OH)2 (△Hf = − 924.7 kJ/mol), which would be the other compound that could be formed. Hence, MgO is the most thermodynamically stable compound48. Likewise, the presence of CaCO3 in the treated samples in the range of 900 to 950 °C is attributed to the biogenic source of HAp50, since this range of heat treatment temperature is not sufficient to promote the dissociation of CaCO3 into CaO and CO2 yet51.The behavior of bone powder without heat treatment, observed in the diffraction patterns in Fig. 3 and CaO phases were identified. The total decomposition of calcite depends on the working atmosphere and can occur above 900 °C, where CaO is obtained, as reported by Galán et al.51. Subsequently, in the samples obtained at temperatures in the range of 1100 to 1200 °C, CaO and CaCO3 presence was not evidenced. However, the α- and β-TCP phases were identified. The CaO and CaCO3 phases’ disappearance, together with the formation of tricalcium phosphates, could be related to a possible reaction of CaCO3 with the phosphate ions released from the HAp lattice due to the CO32− incorporation. The incorporation of carbonate ions into the HAp lattice would lead to the release of phosphate ions from the cell, resulting in the formula Ca10−x(PO4)6−x(CO3)x(OH)2−x reported by Siddiqui et al.8. Likewise, it has also been reported that tricalcium phosphates can be obtained from the reaction between calcium carbonate and phosphate ions at temperatures around 1150 °C, according to Chabchoub et al. and Bohner et al.54. Furthermore, the lattice in the BHAp samples is expanded, compared to the stoichiometric one, according to the cell volumes’ values obtained and reported in Table 55.In the samples treated above 1000 °C, the CaCO40, the coalescence effect occurs in this range of temperature for calcined bovine bone powders. Additionally, Londoño-Restrepo et al.18 reported coalescence phenomena in the porcine bone powders associated with crystal growth due to the calcination temperature. They also mentioned that, as the calcination temperature increases, the crystal growth continues, and it is observed on the c-axis.The morphologies for samples prepared at temperatures of 900 and 950 °C observed in Fig. 57. This growth generates intergranular voids of greater size than those observed in the samples’ images obtained with lower temperatures. Finally, the images show sub-micrometric spherical grains associated with the MgO phase observed in XRD. Ramirez-Gutierrez et al.14 and Forero-Sossa et al.20 have also reported these formations in previous works.In this work, the growth of grains occurs in the c-axis in the samples treated at temperatures higher than 1000 °C, which agrees with previous reports for the growth of HAp crystals40 and Asadollahzadeh et al.44 mentioned the reduction of the intensities of the carbonate groups at these calcination temperatures. However, these authors did not carry out thermal treatments above this temperature. In particular, Sroka et al.36 studied the influence of the carbonate ions in HAp, finding that when this ion enters the cell and replaces the phosphate ion, the shoulder’s presence at 1044 cm−1 is observed in the FTIR spectra using the ATR mode36. In this work, this shoulder is observed for samples with heat treatment above 1050 °C. Likewise, a decrease in the phosphate group’s intensity was observed, which could be associated with incorporating the carbonate ion for these samples in this temperature range.Regarding the functional groups’ behavior obtained by FTIR for the range of 900 and 950 °C, some authors such as Sofronia et al.8. On the other hand, Kokubo’s solution in a static environment has been widely criticized due to its low reaction rate compared to other simulated biological solutions. Using these characteristics is possible to obtain false negatives, such as the β-TCP phase, since this does not show bone-like apatite growth on the surface when immersed in SBF. However, it is a biomaterial known for its biological response in in-vivo assays58. Based on this, it is possible that in other simulated media, such as Hank’s solution, the formation of different phases can be observed due to the ionic interaction between the ceramic and the fluid, as mentioned by Forero-Sossa et al.20.Furthermore, based on the SEM and FTIR results, the non-formation of bone-like apatite in the samples at 900 and 950 °C could be associated with no carbonate substitution in the HAp cell at these temperatures61. Some authors have also reported that the solubility of TCP in physiological environments is greater than that of HAp, which would increase the reaction speed of samples that present these phases. Those results agree with the findings observed in this work54.Moreover, the samples with calcination temperatures above 1000 °C showed significant changes in the functional groups’ intensities and the samples’ surface morphology. These results determined that bone-like apatite forms on the samples’ surface were obtained in the temperature range of 1000 to 1200 °C when exposed to SBF in this temperature range. Particularly, the samples treated with temperatures higher than 1100 °C show the growth of morphologies associated with bone-like apatite. This group of samples’ higher bioactivity could be related to incorporating the carbonate ion in the HAp lattice and the combination of phases (HAp + TCP). According to various works, the phase combination presents improved bioactivity compared to individual ones3 phase was found. Likewise, between 1000 and 1050 °C, the CaO phase and CaCO3 coexist. Finally, , between 1100 and 1200 °C, the formation of TCP’s was identified. This result could be associated with the reaction between CaCO3 and phosphate ions released from the HAp cell due to the carbonate ions incorporation on it. High calcination temperatures mediate the proposed mechanism.The effect of the calcination temperature on the physicochemical properties and the bioactive response of BHAp from the porcine source was determined. It was found that the HAp and MgO phases are present in all the samples with the different calcination temperatures studied. Additionally, between 900 and 950 °C, the CaCOUsing the FTIR results, it was determined that the replacement of the phosphate ions by carbonate ones is greater in the samples prepared at high temperatures. Then, the B-type substitution is promoted at calcination temperatures between 1150 and 1200 °C, likewise, the A- and B-type substitutions were favored after the bioactivity test.The samples thermally treated at 900 and 950 °C did not show changes in the spectra and the micrographs during the bioactivity test. However, for the samples treated at temperatures above 1000 °C, there were changes related to bone-like apatite formation on the samples’ surface. Finally, for the samples with a calcination temperature between 1100 and 1200 °C, tricalcium phosphates’ presence generates a higher reaction speed than the other samples that did not present these additional phases.Supplementary Information.


Transarterial radioembolization (TARE) is increasingly used as an alternative to transarterial chemoembolization (TACE) for the treatment of hepatocellular carcinoma (HCC). We aimed to perform an overall and individual patient data (IPD) meta‐analysis of studies comparing TACE and TARE.We performed a systematic literature search using pre‐specified keywords with the aid of an informationist for articles from inception to 3/2020. The primary endpoint was overall survival (OS), and the secondary endpoint was time to progression (TTP).Seventeen studies met inclusion criteria with 2465 unique patients, with one randomized trial, 4 prospective studies and 12 retrospective studies. Barcelona Clinic Liver Cancer (BCLC) stage B (42.8%) was the most common stage followed by BCLC A (30.3%) and BCLC C (29.0%). There was no difference in OS between the two modalities . In three studies with available TTP data, TARE resulted in a longer TTP than TACE . IPD‐level meta‐analysis of 311 patients from three studies showed no difference in overall OS between the two modalities including among subgroups stratified by tumor stage and liver function. Limitations of the current literature include inconsistent length of follow‐up, inconsistency in response criteria, and safety reporting.Current data suggest TARE provides significantly longer TTP than TACE, although the two treatments do not significantly differ in terms of OS. Given limitations of the current data, there is rationale for prospective studies comparing these modalities. In this overall and individual level meta‐analysis, patients with hepatocellular carcinoma treated with transarterial chemoembolization and transarterial radioembolization (TARE) showed similar survival. Patients treated with TARE however, had a longer time to tumor progression. The search strategy was included in Appendix The Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRIMSA) guidelines were used to guide study selection and data collection.2.2The search yielded 1784 unique articles that were screened for inclusion by two independent reviewers (AB and IK). Conflicts were resolved with the assistance of a third reviewer (NP). Studies to be included were more closely analyzed by the authors and selected for appropriateness for data extraction. Data were extracted by each reviewer using standardized forms. Forms collected demographic, liver function, cancer staging, unadjusted survival, time to progression data, and adverse events when available. Study quality assessment was performed with Newcastle‐Ottawa Scale (NOS).2.3The primary endpoint was overall survival (OS), and the secondary endpoint was time to progression (TTP).2.4Authors of all included studies were contacted for data sharing to include patient‐level data to allow IPD meta‐analysis, with the authors of three studies responding. These studies included papers by Moreno‐Luna et al.,2.5SD=SE*n. For (3), we estimated mean as TQ1+Tmed+TQ33 and standard deviation as TQ3−TQ12Φ−10.75n−0.125n+0.25, where T represents time (OS or TTP), Q1 represents the 25th percentile time, med the median time, Q3 the 75th percentile time, Φ−1x the upper x‐th percentile, and n the number of patients receiving that specific treatment. For (4), we estimated mean as TL+2*Tmed+TH4 and standard deviation as TH−TL3.92, where T represents time, either OS or TTP, L represents the lower bound of the confidence interval, med the median time, and H the upper bound of confidence interval.OS and TTP were reported in four different ways: (1) mean and standard deviation, (2) mean and standard error, (3) median and interquartile range, or (4) median and 95% confidence interval. To facilitate meta‐analysis, we harmonized all outcome reporting into mean and standard deviation per (1). For (2), we used reported mean and calculated Overall meta‐analysis was performed comparing TACE and TARE using a random effects model incorporating mean OS/TTP, standard deviation, and n for TACE and TARE recipients. We evaluated mean difference of both OS and TTP. Preplanned subgroup analyses stratifying studies by study quality. We assessed publication bias visually using a funnel plot and numerically with an Egger test.IPD meta‐analysis was performed using data from three studies. The primary outcome was OS, as data on TTP were not available in the studies in which IPD were available. We generated Cox proportional hazard survival models rather than comparing difference in mean survival as these models are more informative. We conducted pre‐specified subgroup analyses based on BCLC stage and CP class, in which we separately evaluated hazard ratio for OS in each study and subgroup, and then meta‐analyzed across studies and within each subgroup  using a random effects meta‐analysis similar to as described above. Finally, we generated in each cohort a multivariable Cox proportional hazard survival model with outcome of OS and predictor of treatment type (TARE vs. TACE), adjusting for age, sex, CP class, and BCLC stage, and meta‐analyzed across the three cohorts as above.p < 0.05 was used for significance in all analyses. All analyses were performed in R version 3.5.1.33.1In total, our initial search revealed 1784 studies, 17 of which met inclusion criteria including 2465 unique patients Figure . Twelve p = 0.008), but otherwise there were no differences between the groups.Patients receiving TARE were significantly more likely to have chronic hepatitis C as the etiology of their liver disease  was the most commonly used modality in the included studies (8/17). Five of the studies used drug‐eluting bead transarterial chemoembolization (DEB‐TACE), while three studies used both cTACE and DEB‐TACE. One study used TACE with degradable starch microspheres (DSM). Each study had a mix of lobar treatment and segmental treatments.With regard to TARE, the majority of the studies (10/17) used TheraSphere while six studies used SIR‐sphere, and one study used both Table . Notably3.3I2 97.5%; p < 0.001). In the three studies with available TTP data, TARE resulted in a significantly longer TTP than TACE  .There was no difference in OS between the two modalities with absolute difference −0.55 months, 95% CI −1.95 to 3.05 (for TARE relative to TACE) . Overall hazard ratio showed no difference in OS between TARE and TACE . The results were consistent in key subgroups stratified by BCLC and CP class   were high quality (NOS ≥ 7) while one study was medium quality (NOS <7) Table . There w) Figure .3.6The included studies featured a wide range of adverse events (AE) data. Only four studies reported data on AEs; however, there was significant heterogeneity in the reporting. Any AE associated with TACE patients was 10.8–73%, while any AE for TARE patients was 10%–44%.4In our updated meta‐analysis, we have demonstrated lack of a difference in overall survival in patients receiving TACE versus TARE; however, time to HCC progression was significantly longer in patients receiving TARE therapy. These findings are concordant with the only randomized data comparing TACE and TARE.In the subgroup analyses, there was no difference in overall survival in patients regardless of the modality received. In studies stratifying TACE or TARE by BCLC class, there is consistent decrements in survival with advancing stages. Similarly, several studies have shown the significant decrements in TACE and TARE effectiveness and safety in CP B and C disease. TARE has also been compared to sorafenib in BCLB B and C disease in two randomized trials and was not associated with a survival benefit,Nevertheless, TACE and TARE remain primary treatment options for a significant proportion of patients with HCC and our analysis supports the efficacy of both. TARE was associated with an increased TTP compared to TARE in a subset of the included studies; however, there are notable deficiencies in radiographic interpretation of tumor progression after radiation therapy that may have contributed to this finding.Our study had several strengths and limitations. First, TACE and TARE technique for administration and patient selection were not standardized across the studies. Most of the studies included were retrospective in design, thus bias such as confounding by indication, differences in imaging interpretation, or unmeasured confounders may have contributed to the results of the analysis. Furthermore, treatment with TARE has evolved with several recent studies including personalized dosimetry as the most effective method for TARE delivery; however, most of the included studies utilized lobar treatment or standardized dosimetry.5Current data suggest TARE can provide significantly longer TTP than TACE, although the two treatments do not significantly differ in terms of overall survival in both our overall and individual patient level meta‐analysis. Safety profiles appeared to favor TARE; however, these data deserve further prospective confirmation. Given the limitations of the current data, there is rationale for comparing these modalities in larger prospective analyses to allow granular comparison of survival, progression, and safety data.Parikh is the guarantor of this article. Roles: (a) Concept: Parikh; (b) Analysis: Parikh, Chen; (c) Data acquisition: All authors; (d) Writing: Parikh, Brown, Kassab, Singal; (e) Critical revision: All authors.Dr. Singal's research is conducted with support from National Institutes of Health U01 CA230694, R01 MD12565. Dr. Parikh's research is conducted with support from National Institutes of Health U01 CA230669. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The funding agencies had no role in design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation of the manuscript.Brown: None. Kassab: None. Massani: None. Townsend: None. Singal: Served as a consultant or on advisory boards for Bayer, FujiFilm Wako Diagnostics, Exact Sciences, Roche, Glycotest, and GRAIL. Soydal: None. Moreno‐Luna: None. Roberts: Consults for AstraZeneca, MJH Life Sciences, and Clinical care options; he advises and received grants from Bayer, Exact Sciences, and Gilead; he advises GRAIL, Tavec, QED Therapeutics, Genentech, Envision, and Eisai and received grants from Ariad, BTG International, GylcoTest, RedHill, Ltd Pharma, and Wako Diagnostics. Chen: None. Parikh: Served as a consultant for Bristol Myers‐Squibb, Exact Sciences, Eli Lilly, and Freenome; has served on advisory boards of Genentech, Eisai, Bayer, Exelixis, Wako/Fujifilm; and has received research funding from Bayer, Target RWE, Exact Sciences, Genentech and Glycotest.The data included in this study were either publicly available or completely de‐identified and were exempt from Institutional Review Board approval.Appendix S1Click here for additional data file.


Poor knowledge, negative attitude, and poor practices were observed among most of the participants. Sensitization and training on AMR and antimicrobial stewardship are recommended to address the KAP score gaps and the observed determinants among veterinary drug dispensers.Antimicrobial resistance (AMR) is an emerging challenge to global public health. The use of antibiotics in the veterinary field is one of the contributing factors to AMR mostly due to poor knowledge, attitudes, and practices (KAP) of dispensers. Veterinary drug dispensers are expected to guide clients on indications, contraindications, and withdrawal periods of veterinary drugs. This study assessed veterinary drug dispensers’ KAP toward AMR and associated potential contributing factors. A cross-sectional study, using a structured questionnaire, was conducted in three main cities of Malawi, namely Mzuzu, Lilongwe, and Blantyre. A total of 68 agrovet shops were selected using a simple random sampling technique. The KAP level was presented descriptively. Bivariate and multivariable analyses were run to investigate the relationships between the independent and outcome variable. Overall, the KAP score for knowledge, attitude, and practices was 46.7%, 49.2%, and 41.6%, respectively. The significant determinants of the knowledge were the practice of asking for a written prescription  ( Antimicrobial resistance (AMR), an emerging public health challenge is increasing worldwide ,2,3,4. GIn the wake of AMR burdens, several sub-Saharan African countries developed AMR preparedness plans, and East African countries reported the strongest AMR response ,11. In cEscherichia coli and from 11.8% to 90.5% for Klebsiella species. Kumwenda et al. [Klebsiella species was , Staphylococcus aureus , Proteus species , and Streptococcus pneumoniae . Furthermore, Musicha et al. [Malawi has the most comprehensive data sets for AMR burden in sub-Saharan Africa, which depicts the growing trend of AMR burden in humans ,16,17,18a et al.  also repa et al.  reporteda et al. ,21, whica et al. ,23.Malawi has unclear AMR surveillance in animals and the environment, despite having less stringent regulations on accessing veterinary drugs ,22,23. VThe prudent use of veterinary drugs depends on the knowledge of the veterinary drug dispensers as well as on the awareness and knowledge of the livestock farmers ,27. MostThe study recruited 68 respondents from agrovet shops. The geographical distribution of the participants included 24 from Blantyre, 32 from Lilongwe, and 12 from Mzuzu. Of the participants, 30.9% (21/68) were female and 69.1% (47/68) were males. The general agrovet shops were the majority 94.1% (64/68) compared to poultry drugs only and feed shops 5.9% (4/68). More than half of agrovet shops 82.4% (56/68) were located within the town centers, while 17.6% (12/68) were located within the residential areas .The overall frequency . The study found a higher frequency of oxytetracycline brands 27.9% (12/43) among the available antibiotic brands. The concentrations of oxytetracycline among the brand names varied a lot which included 2%, 5%, 8%, 10%, 12.5%, and 20%. Other antibiotic brands were sulfa-333 20.9% (9/43), penstrep 9.3% (4/43), gentaject 6.9% (3/43), and colistin 4.6% (2/43), and among least was aliseryl 2.3% (1/43). Aliseryl was observed in all poultry-drugs-only veterinary product shops that participated in the study.p = 0.037). About three-quarters of participants, 76.5% (52/68), knew about AMR and its occurrence in livestock and humans. Furthermore, the majority of the participants knew about the national AMR strategic plan, although the distribution of the KAP score was significantly different across the cities (p = 0.046) (The majority of the participants 75.0% (51/68) were aware of the uses of antibiotics, and 48.5% (33/68) knew that antibiotics could not cure all diseases that affect the livestock. Lilongwe city had a higher KAP score of 90.6% (29/32) compared to the other two cities for knowledge of the curative effects of antimicrobials (= 0.046) .p = 0.028). However, only 10.3% (7/68%) of participants claimed that they asked for written prescriptions from the clients, and very few participants, about 7.3% (5/68), were guided by written prescriptions. About half of the participants 52.9% (36/68) had an interest in knowing whether the person administering the drugs was competent (The majority of the participants 98.5% (67/68) provided information on the use of veterinary drugs, and about 82.4% (56/68) informed the clients about the withdrawal period. Participants in Lilongwe had higher KAP scores for the practice of providing information for the use of veterinary drugs than participants in the Blantyre and Mzuzu cities (ompetent .p = 0.021). A higher proportion of participants 83.8% (57/68) considered that antibiotics should be prescribed only by veterinarians and the distribution of scores was different among the cities (p = 0.011) (The study found that 70.6% (48/68) of participants considered that the occurrence of AMR in livestock was severe, and 89.7% (61/68) of the participants considered drug residue was responsible for AMR in livestock and humans. In addition, 67.7% (46/68) considered careless use of drugs contributed to AMR in livestock, although the distribution of KAP scores was significantly different among the cities—16 for Blantyre, 22 for Lilongwe, and 8 for Mzuzu (= 0.011) .p-0.022, p-0.015, and p-0.039, respectively. Mean scores for the 18–35 age group were higher 29.6 ± 8.1, 27.2 ± 14.3, and 31.3 ± 5.2 than the ≥35 age group for knowledge, attitude, and practices, p-0.017, p-0.022, and p-0.024, respectively  but different for attitude , .p = 0.015); sex (p = 0.001), location of shop (p = 0.001), work experience (p = 0.001), knowledge of the occurrence of AMR in livestock and humans (p = 0.001), the practice of asking for a written prescription (p = 0.001), and the practice of informing customers on withdrawal period (p = 0.001). Thereafter, the variables were screened for multicollinearity using univariate linear regression  had a high-level KAP score for AMR at a cutoff point of 50% and above. Pearson chi-square was run to assess the association between the potential determinants and AMR knowledge. There was an association between high level and the potential determinants such as age (gression .p = 0.024). Female participants were OR: 0.609 (95% CI: 0.3–0.9) times less likely to be knowledgeable about AMR than male participants that knew AMR (p = 0.001), and older participants (≥35) were OR: 0.227 (95% CI: 0.1–0.5) times less likely to be knowledgeable about AMR than participants that knew AMR (p = 0.004).The significant determinants of AMR KAP were sex, age, and the practice of asking for a written prescription. Odds ratios (OR) are presented in This is the first report on the assessment of KAP of veterinary drug dispensers regarding AMR in Malawi. The results of this study demonstrated that there was poor knowledge, negative attitudes, and poor practices among most of the veterinary drug dispensers toward AMR in the three cities that were sampled. The most dispensed class of antibiotics was tetracycline. The following were the observed determinants: the practice of asking for a written prescription, female, and old age of the veterinary drug dispensers.The current study’s finding that the overall mean KAP score for knowledge, attitude, and practice is suboptimal is similar to results in Nigeria, Myanmar, and Morocco ,29,30. TIn addition, the study observed that aliseryl, a brand of antibiotics composed of tetracycline, erythromycin, streptomycin, colistin, and vitamins, is used for noneffective dose as a growth promoter, feed efficiency booster, and production booster on a daily basis in livestock as previously reported in more than seven countries ,35. ThisFurthermore, our findings suggested insufficient knowledge about antimicrobial usage, residue, and resistance among veterinary drug dispensers similar to what was reported in Morocco . MoreoveLike pharmacists in the medical field, veterinary drug dispensers have a role in controlling antibiotic abuse and the spread of AMR ,46. In oThe participants’ attitude was suboptimal, despite obtaining good scores on some questions. Participants’ perception toward specific areas was encouraging and could be used as a cornerstone for the improvement of AMR stewardships . Most paThe study was conducted in three main cities of Malawi, namely, Blantyre, Lilongwe, and Mzuzu . These tA cross-section study was conducted in three main cities of Malawi, namely, Blantyre, Lilongwe, and Mzuzu because of the presence of main agrovet shops . The citA structured questionnaire was developed principally based on questionnaires used in previous similar studies ,51,52,53Questionnaires were prevalidated for relevance, accuracy, clarity, simplicity, and understandability and Cronbach’s alpha coefficient of 0.74, 0.76, and 0.72 for knowledge, practice, and attitude, respectively, indicating the internal consistency and reliability of the study questionnaires . The queData for the five most antibiotics on demand were grouped according to the class of active ingredients. The frequency of the antibiotic classes was calculated based on the number of responses.t-test and the chi-square test [Scores for knowledge, attitude, and practice were calculated by adding correct/positive responses  as previously reported by ,55. Goodare test .®2019. Data analysis was conducted using SPSS Ver. 21  statistical software. Before data analysis, every correct response was accorded a value of 1 and otherwise, and the response was accorded a 0 value. The normality test was done graphically using QQ-plots and Shapiro–Wilk test; thereafter, the Student t-test or One-Way ANOVA was used to compare the mean differences across explanatory variables for knowledge, attitude, and practice scores. The Chi-square test was used to assess the association between AMR knowledge, attitude, and practice and independent variables. Multicollinearity was checked using Variance Inflation Factors (VIF)  and Tolerance . Thereafter, a multivariable linear regression model was fitted, which included variables that retained significance (p < 0.05) at univariate analysis [p-value less than 0.05 were considered significant predictors of AMR knowledge, attitude, and practice.The response alternatives for knowledge, practice, and attitude were mostly dichotomous, presented as “yes” or “no”, meaning “true” or “false”, respectively. Data were cleaned and validated in Microsoft™ Excel Spreadsheet (Microsoft Office Excelanalysis ,55. The This study found poor knowledge, negative attitudes, and poor practices concerning AMR among most of the participants. Sensitization and antimicrobial stewardship training are recommended to address the KAP score gaps and the observed determinants among veterinary drug dispensers. The government should consider ways to scale up its regulations on veterinary drug dispensers. It is imperative to conduct a similar future study among veterinarians to ascertain the reported results. Subsequently, it is critical to strengthen antimicrobial stewardship programmers in the veterinary sector in Malawi.


Rapid and accurate pathogen diagnosis is an urgent unmet clinical need for recurrent urinary tract infection (RUTI) in kidney transplant recipients (KTRs). Metagenomic next-generation sequencing (mNGS) may offer another strategy for diagnosing uropathogens but remains to be studied.Nineteen KTRs with RUTI were collected in this study. The uropathogens were detected and compared by mNGS and urine culture, respectively. Modifications of the anti-infection strategy were also assessed.p < 0.01) and in identification rates for bacteria , for viruses , and for fungi , respectively. mNGS identified a significantly higher proportion of mixed infections than culture . The anti-infection therapies were adjusted in two (33.3%) and 12 (76.9%) cases guided by culture and mNGS, respectively.Rich and diverse pathogens were revealed by mNGS. mNGS was significantly higher than culture in total positive rate (100.0% vs. 31.6%; mNGS has more remarkable etiological diagnostic performance compared with urine culture for KTRs with RUTI to guide anti-infection strategies and, in turn, protect the graft. Kidney transplant confers profound survival benefits for the treatment of end-stage kidney disease. With the widespread application of potent immunosuppressive agents and improved organ preservation techniques recently, the 1-year survival rate of kidney transplants has increased to more than 90% . The perCurrently, conventional urine culture is recommended as an economical and convenient method to detect uropathogens for RUTI in clinical testing and can also be used for drug susceptibility testing (DST). However, this method is time consuming, prone to contamination, and difficult to identify multiple infections, and its sensitivity and specificity are unsatisfactory. Therefore, there is an urgent need to develop rapid and reliable diagnostic techniques for RUTI pathogens to address this problem in clinical practice.Metagenomic next-generation sequencing (mNGS) is an emerging method for the identification of pathogens. Since its successful use in 2008 for detecting new pathogenic infections , mNGS haThis study aimed to evaluate and compare the diagnostic performance of these two methods: urine culture and mNGS, for the rapid and accurate identification of pathogens in KTRs with RUTI.This study was conducted in Henan Provincial People's Hospital, a tertiary teaching hospital in Zhengzhou, China, from July 2019 to May 2021. A total of 19 KTRs diagnosed with post-transplant RUTI were screened and eventually investigated in the present study . The incThe collection of all samples followed the standard operating procedures conforming to the rules of the aseptic technique and was transported to the sequencing laboratory by the cold chain in time.According to the manufacturer's operational guidebook, TIANamp Micro DNA Kit  was used for DNA extraction. DNA extraction was conducted for each sample, while RNA extraction and reverse transcription were applied according to the patient's manifestations at the discretion of the physician's clinical decisions, particularly if a viral infection was suspected.® dsDNA HS Assay Kit . Agilent 2100 Bioanalyzer  was used to evaluate the DNA concentration and fragment size in the library to be sequenced for the quality control of the DNA libraries. DNA nanospheres were prepared by one-step DNB kit . The MGISEQ-200 platform sequenced quality-qualified libraries.The total DNA or cDNA was subjected to library construction through an end-repair method. A specific tag sequence was introduced at the end of each library. The library concentration was determined by Qubit 4.0 nucleic acid fluorescence quantitative analyzer  and Qubitftp://ftp.ncbi.nlm.nih.gov/genomes/) and other public databases.After removing low-quality (<35 bp) and low-complexity reads according to PRINSEQ (version 0.20.4) and computational subtracting human host sequences mapped to the human reference genome (hg38) from the sequencing data by Burrows–Wheeler Alignment (0.7.10-r789), high-quality sequences were generated. The remaining non-host sequences were matched and classified with four self-constructed genome databases of pathogenic microorganisms consisting of bacteria, fungi, parasites, and viruses, which were downloaded from the National Center for Biotechnology Information  and MacConkey agar plate (BD BBL prepared plated media) were used for culture of bacteria at 37°C under aerobic, microaerophilic, or anaerobic conditions for 24 h. If pinpoint growth was seen at 24 h, the agars were held for another 24 h under the same conditions. Each distinct colony morphology was subcultured at 48 h to obtain pure culture for microbial identification. The fungi were cultured on Sabouraud dextrose agar plates at 37 or 27°C for 1–5 days. A positive urine culture is defined as ≥10,000 colony-forming units of a potential uropathogenic per mL of urine . All othP < 0.05.Continuous data conforming to a normal distribution were reported as the mean ± standard deviation value; continuous data outside the normal distribution were presented as median and interquartile range (IQR). Categorical data were presented as the number of cases and percentage (%). The McNemar Chi-square test was conducted to compare the results of mNGS and traditional culture to determine the differences. Fisher's exact probability test was used to compare the proportion of patients with negative and positive cultures who changed the antibiotic treatment based on the mNGS results. Our data, prior literature, and power calculation determined sample sizes. Data analyses were performed using Statistical Package for the Social Sciences (SPSS) version 24.0 statistical software . All P-values were two-sided, and statistical significance was defined as All kidney transplants in this study were performed in Henan Provincial People's Hospital. No organs were procured from prisoners or other institutionalized persons, and all organ donations were contributed voluntarily. Participants provided written informed consent before the collection of samples. The study was conducted following the Declaration of Helsinki. Ethical approval was provided by the Clinical Research Ethics Committee of Henan Provincial People's Hospital.Details of the clinical characteristics of the 19 KTRs with RUTI enrolled in this study are presented in All KTRs received anti-thymocyte globulin induction to prevent renal allograft rejection before surgery. After the transplant, they were initially treated with the standard immunosuppressive regimen, consisting of tacrolimus, mycophenolate mofetil (MMF), and prednisone. The tacrolimus dosage was weight-based and then adjusted according to close monitoring to maintain tacrolimus blood concentrations within the therapeutic range to ensure efficacy and safety.Escherichia coli , Klebsiella pneumonia , Staphylococcus epidermidis , Micrococcus luteus , and Lactobacillus iners . The positive rate of viruses was 57.9% (11/19) by mNGS, of which JC polyomavirus , Cytomegalovirus , and Torque ateno virus  were the most commonly seen. The positive rate of fungi was 42.1% (8/19) by mNGS, of which Malassezia restricta  and Aspergillus flavus  were the most commonly seen.A total of 19 samples were tested by mNGS. A total of 19 bacterial species were detected in 17 samples (89.5%), six viruses in 11 samples (57.9%), and six fungal species in eight samples (42.1%). Escherichia coli , Enterococcus faecium , Klebsiella pneumoniae , and Staphylococcus epidermidis . No fungus was found in all urine cultures.Colony growth was observed in six cases  by urine culture . Speciesp < 0.001). In comparison with culture, better performance of mNGS in detecting viruses and fungi  was evident in these results.All samples underwent both mNGS and urine culture methods. Enterococcus faecium and Staphylococcus epidermidis was detected positive by culture but failed to be reported by mNGS in patient P8. mNGS missed two bacteria that tested positive by culture, which may be related to the patient's antibiotic treatment before mNGS. Among the 13 culture-negative cases, mNGS results were all positive, of which 11 cases were bacterial positive, seven cases virtual positive, and eight cases fungal positive. Notably, of these fungi, none were detected by culture according to the positive criteria. It is noteworthy that mNGS has tremendous advantages in detecting viruses that traditional culture methods do not, indicating mNGS' potency in detecting unexpected viruses. In addition, using mNGS, the diagnostic speed can be nearly two times faster than the traditional culture method (2–3 vs. 3–6 days).The six positive cases found in the urine culture were a subset of the positive cases in mNGS, while the corresponding pathogens detected by the two methods were not identical. Most of the pathogens found by mNGS were not detected by urine culture. However, most of the pathogens detected by urine culture can be detected by mNGS. Nevertheless, the infection of p < 0.001).In the multipathogen infection cases, mNGS detected a mixture of bacteria in 13 cases (68.4%), a dual virus infection in four cases (21.1%), and a dual fungi infection in two cases (10.5%). Mixed infections of bacteria and viruses were detected in six cases (31.6%). Mixed fungal and bacterial infections were detected in two cases (10.5%). Mixed infection of viruses and fungi was detected in one case (5.3%). Mixed infections of bacteria, fungi, and viruses were detected in four cases (21.1%). By comparison, mNGS showed a significantly higher proportion of multipathogen infections identified than culture -Ia, CTX-M-50, KPC-12, SHV-110, AAC(6')-Ib7, mdtN, mdtF, efrB, and tet(C), which cause resistance to cephalosporins, carbapenems, macrolides, aminoglycoside, tetracyclines, or nucleoside antibiotics.Genes encoding antimicrobial resistance were determined from bacterial genome sequences using mNGS. Antibiotic resistance genes were detected in five  patients. Three kinds of bacteria are involved: p = 0.129). Meanwhile, 69.2% (9/13) of the solely mNGS-positive cases and 66.7% (4/6) of culture-positive cases showed no RUTI at 6 months of follow-up . The cure rate was 68.4% (13/19).All patients were empirically given antibiotics for anti-infection treatment after admission, and the degree of immunosuppression was reduced. Antibiotics were adjusted in time according to the results of mNGS or urine culture and DST . In cultFor KTRs, urinary tract infections present recurrent and refractory characteristics because of the long-term application of immunosuppressants, the anatomical changes of the urinary system, and the repeated dialysis before transplant, which may result in impaired kidney function, and graft failure, or even death , 4. HoweEnterococcus faecalis infection in the urine, which was quickly controlled with the appropriate antibiotics. Mouraviev and Mcdonald . We found that the urinary tract in KTRs with RUTI harbored a rich and complex microbiota by mNGS, in which the dominant groups of bacteria were Escherichia coli, Klebsiella pneumoniae, Staphylococcus epidermidis, Micrococcus luteus, Lactobacillus iners, and Enterococcus. Previous studies showed that Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterococcus, and Staphylococcus putrefaciens were the most common pathogenic microorganisms in general urinary tract infections . The identification of infections of multiple pathogens can guide effective anti-infection treatment. Additionally, the information on antibiotic resistance provided by mNGS from urine samples of KTRs with RUTI can help evaluate the infection risk. We analyzed the antibiotic resistance genes of the bacteria detected in the mNGS test. Five patients detected three drug-resistant bacteria, including Klebsiella pneumoniae, Escherichia coli, and Enterococcus faecalis, suggesting that these three bacteria are common drug-resistant bacteria in KTRs with RUTI. Among them, Klebsiella pneumoniae was detected with various drug-resistant genes, which brought difficulties to the treatment. Nevertheless, we achieved an excellent curative effect after the adjustment of antibiotics in time according to mNGS, demonstrating the advantages of mNGS in treating KTRs with RUTI.Apart from this, we also found that every patient after transplant diagnosed with RUTI could carry a variety of pathogens in the urethra. mNGS showed a significantly higher proportion of poly-microbial infections identified than culture  can be found at: The study involving human participants was reviewed and approved by the Clinical Research Ethics Committee of Henan Provincial People's Hospital. The patients/participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.WD and XT contributed to the study conception, design, and drafting of the manuscript. WD, YY, and JZ contributed to the acquisition, analysis, interpretation of data, and performed statistical analyses. XT and TY provided administrative, technical, material support, and study supervision. All authors contributed to the article and approved the submitted version.This work was supported by the Project of Science and Technology of Henan Province (Nos. 202102310438 and 222102310264), the 23456 Talent Project Foundation of Henan Provincial People's Hospital (No. ZC20200327), the Joint Construction Project of Henan Medical Science and Technology Research Plan (Nos. LHGJ20210042 and LHGJ20210068), and the Foundation of Henan Educational Committee (No. 22A320012).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Various neurotrauma and neurodegenerative disorders alter the communication between the brain and the regions of the spinal cord that control movement. The consequences are permanent motor deficits or even complete paralysis.The neurons responsible for the production of leg and arm movements are located in the lumbar and cervical regions of the spinal cord, respectively. Epidural electrical stimulation (EES) applied over these regions of the spinal cord can reactivate these neurons . EvidencThis understanding translates into stimulation protocols that target the individual dorsal roots with a timing that reproduces the natural spatio-temporal activation patterns of motor neurons underlying the intended movement ,3. SpatiWe reasoned that a brain–spine interface (BSI) could remedy these limitations. The underlying idea was to establish a natural link between the brain and spinal cord to enable patients to exert direct control over the protocols of stimulation Fig. .The implementation of this digital bridge involves several neurotechnological challenges, including the capability to decode motor intentions from neural recordings of the cerebral cortex. Various strategies have been tested to operate neuroprosthetic systems with neural recordings, from non-invasive to highly invasive neurotechnologies . For exaWe concluded that validating the concept of BSI in preclinical models would benefit from the highest possible resolution. We therefore selected intracortical microelectrodes to record neural activity from the cerebral cortex. We implanted an intracortical 96-electrode array into the primary motor cortex of nonhuman primates and interfaced this array with an upgraded clinical implantable pulse generator (IPG) enabling real-time control of EES through a wireless bridge. This technology was critical since walking requires the use of untethered systems to enable unconstrained mobility. We thus pioneered a BSI whereby the detection of gait events triggered electrical spinal-cord stimulation protocols that aimed to elicit these events. This BSI restored voluntary control of movements from a paralysed leg in a nonhuman primate model of SCI . We receThese studies have provided critical proofs of concept on the ability of BSIs to restore some degree of control over leg and arm movements after paralysis. Our next objective is to test these concepts clinically. For these applications, we believe that electrocorticographic (ECoG) signals offer the best compromise between invasiveness and spatial resolution. ECoG recordings have been shown to provide sufficient temporal and spatial resolution to decode motor intentions from both leg and arm regions, to remain stable over extensive periods of time, and to withstand movement-related artifacts . MoreoveThe second key neurotechnology for the design of a clinically viable BSI is an IPG with ultrafast control over multiple stimulation waveforms via wireless links . This IPG must be interfaced with a surgical paddle lead that integrates an appropriate density and distribution of electrodes to recruit the individual dorsal roots projecting to the spinal segments embedding the targeted motor neurons. The topology of the dorsal roots differs significantly across the human population, suggesting that a library of paddle leads may be necessary for large-scale deployment of a clinically viable BSI.The choice of EES technology and epidural electrocorticographic recording will enable long-term use of the BSI system. Indeed, EES has been routinely used to treat chronic pain for >50 years. Stimulation remains stable over decades, only requiring surgical replacements in a minority of cases . The lonThe therapeutic impact of BSI technologies may not be limited to the immediate restoration of movements. Evidence suggests that this type of neuroprosthetic system triggers neuroplasticity of residual nerve connections, which may augment neurological recovery even when the BSI is turned off . For exaBSI technologies are amongst the most promising solutions to restore some degree of control over leg and arm movements in people with paralysis. Recent technological breakthroughs in neuroelectronics, signal processing, machine learning, and computational modeling have opened a realistic path to design fully implantable clinical BSIs that could have a real medical, societal and economic impact.


The effect of laparoscopic gastrectomy (LG) for the treatment of advanced gastric cancer (AGC) is still controversial. The aim of this meta-analysis was to contrast the short- and long-term outcomes of laparoscopic versus conventional open gastrectomy (OG) for patients with AGC.Databases including PubMed, Embase, Scopus, and Cochrane Library were systematically searched until December 2021 for randomized controlled trial-enrolled patients undergoing LG or OG for the treatment of AGC. Short-term outcomes were overall postoperative complications, anastomotic leakage, number of retrieved lymph node, surgical time, blood loss, length of hospital stay, and short-term mortality. Long-term outcomes were survival rates at 1, 3, and 5 years.2 = 34%) and anastomotic leakage  was found. Compared with the open approach, patients receiving LG had fewer blood loss  and shorter length of hospital stay . However, the LG was associated with a lower number of retrieved lymph nodes  and longer surgical time . Furthermore, there were no differences between LG and OG groups in short-term mortality and survival rate at 1, 3, and 5 years.A total of 12 trials involving 4,101 patients  were included. No effect on overall postoperative complications . Gastric cancer is one of the most common cancers and a main economic burden worldwide . AccordiNowadays, the LG has gained growing popularity in the treatment of EGC since this minimally invasive technique has some definite benefits including lower postoperative complications, faster recovery, shortened postoperative length of stay, and better quality of life. Previously, several well-designed randomized controlled trials (RCTs) from China, Korea, and Japan demonstrated the beneficial short-term outcomes of laparoscopic distal gastrectomy (LDG) including less blood loss and postoperative pain, faster recovery, and shorter hospital stay, and similar oncologic safety to the open approach –10. HoweRecently, the CLASS-01  and KLASWe conducted this meta-analysis according to the updated PRISRMA statement  (SuppleThe inclusion criteria were as follows: 1) population: adult patients (older than 18 years) with AGC; 2) intervention: laparoscopic surgery for gastrectomy; 3) comparison: open surgery for gastrectomy; 4) outcomes: short-term outcomes including postoperative complication, number of retrieved lymph nodes, surgical time, blood loss, length of hospital stay, and short-term mortality . Long-term outcomes were survival rate at 1, 3, and 5 years, including OS rate and disease-free survival (DFS) rate; 5) design: RCT.The data from included trials were independently extracted by two reviewers (JJ and SW). The characteristics of included studies  are recorded in For the methodological quality of including studies, two authors (JJ and SW) independently assessed the quality by using the Cochrane risk-of-bias tool .2) statistics  with 95% confidence interval (CI) for dichotomous outcomes, and continuous outcomes were pooled as mean difference (MD) with 95% CI. The meta-analysis of OS and DFS used the hazard ratio (HR) with 95% CI reported in the primary studies. If the primary studies did not provide the HR data, we obtained the HR data by digitizing the Kaplan–Meier survival curves . The hetatistics . Substanion bias .A predefined subgroup analysis was performed based on the extent of resection  and tumor stage . In addition, a sensitivity analysis by omitting each one trial at a time was performed to explore the effect of individual trials.The initial search identified 1,567 articles , 802 were duplications, and 708 studies were excluded through title and abstract screening. In the full-text assessments, 45 studies were further excluded with reasons and a total of 12 trials with 17 articles , 15–28 wIn addition, the number of retrieved lymph nodes, length of hospital stay, and blood loss in two trials , 20 wereThe quality assessment results are presented in 2 = 91%) and similar 5-year survival rate .The funnel plot and Egger’s test were used to evaluate the publication bias  and tumor stage  were performed to explore the potential discrepant treatment effect of different subgroups , we diviThe extent of resection had no effect on the overall postoperative complications, anastomotic leakage, short-term mortality, and long-term outcomes. Similarly, there was no significant difference in minor and major complications between the LG and OG groups. The beneficial effect of LG in reducing the length of hospital stay and blood loss was more significant after total gastrectomy than partial gastrectomy. Moreover, compared with total gastrectomy, patients receiving partial gastrectomy by a laparoscopic route was associated with more significantly longer surgical time and lower number of retrieved lymph nodes than open surgery.Regarding tumor stage, five trials , 21, 25 In the sensitivity analysis, the LG was relevant to the obvious decrease in postoperative complications  after omitting the CLASS-01 trial, indicating the poor robustness. Furthermore, other short- and long-term outcomes showed no significant differences with primary results , difficulty , efficiency , and its long-term oncologic results (OS and DFS rates). The results of our meta-analysis indicate that the short-term outcomes consisting of blood loss and length of hospital stay are in favor of a laparoscopic approach, especially for total gastrectomy. Since the advanced laparoscopic approach provides a magnified surgical view while minimizing the length of the incision, a more delicate surgical manipulation of the organs, vessels, and nerves could be achieved during operation . In addiThe overall postoperative complications, including minor and major complications, were similar between the two surgical procedures in our study. However, a recent meta-analysis of data from 6 RCTs and 18 non-randomized trials found that LG was associated with a lower postoperative complication rate, with a significantly lower incidence of medical and minor surgical complications . The difBased on the updated studies, LG requires a longer surgical time, which is in line with the results of all included trials. Compared with open approaches, laparoscopic techniques are more complex and less flexible. Frequently cleaning cameras and changing instruments during operation can also extend the surgical time , 43. In Although the result of our meta-analysis indicates that the number of retrieved lymph nodes was lower in the LG group, the mean number of retrieved lymph nodes in the LG group was 32.45 (95% CI 29.01 to 35.89). Based on the American Joint Committee on Cancer, an adequate dissection should include at least 15 lymph nodes for patients with gastric cancer to ensure accurate and robust N staging . A recenFurthermore, the learning curve was proved to have significant effects on most of the important surgical and short-term recovery outcome parameters . Yoo et However, some limitations of our meta-analysis must be acknowledged. First of all, the sample size of some included trials was relatively small, which may decrease the credibility of the results in our study or lead to small study effect bias . SecondlLast but not least, there was significant heterogeneity in some pooled estimates, which might be explained by differences in sample sizes, surgeons’ experience, perioperative care protocols, surgical technique, pre- and postoperative chemotherapy, and other factors. Variations in sample size among studies were large, and some studies enrolled patients during a wide study interval, which may have introduced biases due to a progression in mastering the surgical skills and improvements in surgical instruments.Our findings, which are contingent on rigorous meta-analyses of high-quality RCTs, suggest that LG offers improved short-term outcomes including shorter hospital stays and fewer blood loss, with comparable postoperative complications, short-term mortality, and long-term survival rates when compared to the open approach. However, considering the significant heterogeneity, more RCTs are needed to further evaluate the clinical outcomes of LG versus OG for patients with AGC. Furthermore, this updated meta-analysis could be the basis of future meta-analyses, as the inclusion criteria, statistical analysis, and short- and long-term outcomes were clearly defined and meticulously analyzed.The original contributions presented in the study are included in the article/JJ and SW conceived the idea, performed the analysis, and drafted the initial draft writing of this paper. GY, JW, and XX contributed to the collection and interpretation of data. KZ helped to frame the idea of the study and provided technical support. SW contributed to the revision of this paper and the final approval of the version to be published. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The strains Bifidobacterium adolescentis ATCC 15703 and Bacillus cereus ATCC 9634 were chosen as the model probiotic and pathogen. Oligofructose Orafti P95 (OF) was used as the prebiotic at concentrations of 2, 5, 7, 10, 12, and 15 g/L of the medium. In the first stage, the system was inoculated with Bifidobacterium, and a dynamic equilibrium  was achieved. Then, the system was contaminated with a 3-day Bacillus suspension (spores). The microbial count, as well as the concentration of acids and residual carbohydrates, was measured. A Bacillus monoculture was studied as a control. The stationary count of Bacillus in monoculture was markedly higher. An increase (up to 8 h) in the lag phase was observed for higher prebiotic concentrations. The specific growth rate in the exponential phase varied at different OF concentrations. Thus, the OF concentration influenced two key events of bacterial infection, which together determine when the maximal pathogen count will be reached. The mathematical models were developed, and their accuracies were acceptable for Bifidobacterium (relative errors ranging from 1.00% to 2.58%) and Bacillus (relative errors ranging from 0.74% to 2.78%) count prediction.The diversity and the stability of the microbial community are associated with microecological interactions between its members. Antagonism is one type of interaction, which particularly determines the benefits that probiotics bring to host health by suppressing opportunistic pathogens and microbial contaminants in food. Mathematical models allow for quantitatively predicting intrapopulation relationships. The aim of this study was to create predictive models for bacterial contamination outcomes depending on the probiotic antagonism and prebiotic concentration. This should allow an improvement in the screening of synbiotic composition for preventing gut microbial infections. The functional model (fermentation) was based on a three-stage continuous system, and the distal colon section (N The study of interactions between members of the microbial community is a rather complicated but extremely important task, since most microorganisms naturally enter these systems. The intestinal microbial community has the most significant impact on the health of the host, and the possibility of its modulation by probiotics , prebiotThe main advantage of functional intestine models in vitro is the ability to obtain highly reproducible results due to the exclusion of a number of external factors, as well as the ability to strictly control the parameters. From an ethical point of view, the use of models does not practically require such hard restrictions as trials on humans, and it is much more humane than trials on animals. Moreover, since pharmaceutical procedures and dietary studies usually take a long time, representative models in vitro can significantly speed up the result. Lastly, such studies are less expensive ,6.Currently, models are used that simulate not only the conditions of the gastrointestinal tract such as pH, temperature, and atmospheric composition, but also the relationship of the microbiota with cells of the host intestinal epithelium and mucin, as well as the immune reactions. Examples include (1) the Transwell “apical anaerobic model of the intestinal epithelial barrier”, (2) the host–microbiota interaction (HMI) model, (3) the “Human oxygen–Bacteria anaerobic” (HoxBan) system, (4) the human gut on a chip, and (5) the HuMiX model . HoweverStaphylococcus aureus contamination of the gut microbiota [The three-stage continuous model was firstly proposed by Gibson et al. in 1988 . Later, crobiota . Furthercrobiota .Bifidobacterium and Lactobacillus. It was also shown that human indigestible fungal polyphenols (proanthocyanidins) were metabolized by the microbial community members, resulting in an antioxidant effect [One modification of the model consisting of a fermenter  is intent effect .Listeria monocytogenes, Staphylococcus aureus, Escherichia coli) and lactic acid bacteria (LAB) in artificial media or foods [There are various types of interactions in microbial communities: resource competition, metabolic interactions , allelopathy , etc. . It is por foods ,22,23,24or foods . In thesor foods . It takeor foods . The kinor foods . The advor foods . It shouBifidobacterium  and Bacillus cereus (as a pathogen). The proximal intestine was considered as representative for compiling a mathematical model; accordingly, the cultivation was carried out in one fermenter.Previously, we proposed and tested, under the conditions of static coculture, a model of the inhibition of pathogen growth by probiotics, in which the measure of interaction (antagonism) is expressed through the production of organic acids (lactic and acetic acids). Such a model allowed us to evaluate the effect of prebiotics ,31. HoweBifidobacterium adolescentis VKPM AC1662 (corresponding to ATCC 15703) was considered a model probiotic with high β-fructofuranosidase activity [Bacillus cereus VKPM B8076 (corresponding to ATCC 9634) was used as a model foodborne pathogen. The freeze-dried samples were purchased from the Russian National Collection of Industrial Microorganisms  and stored at temperatures not exceeding 8 °C until use.The strain activity ,32. The 4)2SO4, 5; MgSO4·7H2O, 0.2; FeSO4·7H2O, 0.01; MnSO4·7H2O, 0.007; NaCl, 0.01; cysteine , 0.5; Tween-80, 1; ascorbic acid , 1. The pH was adjusted to 7.0. Oligofructose  was used as a standard prebiotic. A concentrated OF solution in distilled water was prepared. The sterilization was carried out at 115 °C for 30 min.A carbohydrate-free medium and carbohydrate solution were prepared, sterilized separately, and mixed before inoculation. The carbohydrate-free medium (according to  with somBifidobacterium or Bacillus was performed in the vessels with immediate sparging by N2 (extra pure) through a vent branch which reached the bottom. The inoculates were incubated at 37 °C with shaking (180 rpm) overnight.The strain samples were restored in sterile phosphate-buffered saline (PBS), transferred into tubes with a sterile culture medium, and incubated at 37 °C. The sealed vessels with two branches were supplied with membrane autoclavable vent filters , and clamps were applied for the inoculate preparation. The vessels were sterilized with a carbohydrate-free medium. The OF solutions were aseptically added to the vessel before inoculation to obtain the same concentration as in the fermentation (see below). Then, the inoculation of the daily culture of 2  sensors. The control block of the bioreactor was provided with four peristaltic pumps, applied for the inflow of carbohydrate-free medium and carbohydrate solution, the outflow of cultural fluid, and the adjustment of pH. The continuous fermentations were carried out at two stages; the monoculture of Bifidobacterium was maintained until dynamic equilibrium was reached at the first stage, and the contamination with Bacillus spores was performed at the second stage. The bioreactor was sterilized with carbohydrate-free medium. All connections and open-volume manipulations were performed aseptically to avoid contamination. The additives were introduced through a flask in a laminar flow cabinet located in the immediate vicinity of the unit. Since the strains used in the study were not biohazardous (biosafety level 1), the unit was installed on a standard open laboratory bench without the use of special containment equipment. The sterile OF solution was introduced aseptically through the inoculation flask. The concentrations of OF were varied for Bifidobacterium monoculture experiments  and coculture experiments . The culture medium was sparged with nitrogen (pO2 < 0.5). The fermentation conditions corresponding to the descending colon were a temperature of 37 °C, pH of 6.8, and anaerobic atmosphere.The fermentations were carried out in a unit  based onBifidobacterium strain was inoculated, and the fermenter was bubbled repeatedly. One hour after inoculation, the sterile carbohydrate-free medium (from bottle 11) and OF solution (from bottle 10) were continuously supplied to the bioreactor in a volume ratio of 2:1, and the cultural fluid was supplied to the bottle for biosuspension collection (8) in an equal volume. The dilution rate was 0.04 h−1. The pH was maintained at 6.8 by adding a 20% w/w solution of sodium hydroxide. The level of dissolved oxygen was controlled by a pO2 sensor (<0.5%). To create anaerobic conditions, the fermenter was bubbled with nitrogen (extra pure) at least twice a day. These conditions were considered as close as possible to those of the descending colon [Bacillus cereus ATCC 9634. In the control experiment, only the monoculture of B. cereus ATCC 9634 was inoculated.An overnight culture (approximately 16 h) of the llection  in an eqBacillus cereus and Bifidobacterium adolescentis. The dilutions were plated on MRS agar [Bacillus counting. BFM agar [Bifidobacterium enumeration. The pH was adjusted to 5.5 by adding propionic acid (5 mL per 1 L of the medium) immediately after sterilization . Sterile polystyrene Petri dishes with vents  containing BFM agar were plated and placed in BD GasPak™ anaerobic containers . The incubation was carried out at 37 °C. The measurements were performed in triplicate. The specific growth rate was calculated as the slope of the log10 bacterial count.Tenfold serial dilutions in sterile PBS were made and plated on the appropriate medium, and the incubation was carried out at selective conditions for separate enumeration of MRS agar  and incuBFM agar  was appl2SO4 (mobile phase) with an injection volume of 3 µL. The organic acids were diluted in 0.002 M H2SO4 to concentrations of 1, 5, and 10 mg/mL to prepare the organic acid calibration solution. The qualitative identification was carried out according to the retention time, and the external standard method and the chromatographic peak squares were applied for quantification.High-performance liquid chromatography (HPLC) was applied for organic (lactic and acetic) acid detection and quantification as described previously , with so®, Saint Petersburg, Russia) with a quartz capillary . The supernatants of the samples after centrifugation  were additionally purified to remove protein impurities on a centrifugal filter unit  by centrifugation at 5500 rpm at 10 °C for 20 min. A solution of 0.5 mM tetradecyltrimethylammonium bromide and 25 mM pyridine-2,6-dicarboxylic acid  in 170 mM NaOH was used as the background electrolyte. The temperature was 20 °C and the wavelength was 230 nm for indirect photometric detection of carbohydrates.The OF monomers (glucose and fructose) and homologs with different degrees of polymerization were detected using capillary electrophoresis (HPCE) as described previously ,37, withBifidobacterium during continuous cultivation, several factors were taken into account. Firstly, at low flow rate, some of the cells will die due to suppressing conditions. Therefore, at each moment, there will be a dynamic balance between the total number of cells  cells according to the following expression:To describe the growth kinetics of −1) and death rate (−1). Moreover, both living and dead cells will be washed out according to the dilution rate (D). This state can be described by the following system of equations:Secondly, the population dynamics of each subpopulation will be determined by the following rate constants : specifiBifidobacterium will be limited by the carbon substrate (S), which can be described by the Monod equation [Bifidobacterium (h−1); Bifidobacterium by lactic and acetic acids, respectively (mg/mL).Thirdly, the growth of equation . The groequation . Then, tBifidobacterium death (h−1), and Bifidobacterium by lactic and acetic acids, respectively (mg/mL), with a similar biological meaning to the saturation constant in the Monod equation.Fourthly, it was assumed that the rate of death will also be determined by the concentrations of metabolic products. Since it was difficult to find the corresponding equation in the literature, the following expression is proposed:Lastly, the concentrations of the substrate and products in the fermenter will not immediately reach a steady state, and their change can be described by standard equations .(5){−dSBifidobacterium) (mg/CFU), Here, Bifidobacterium under conditions simulating the intestine (at a low dilution rate) can be described by the following system of equations:Thus, the growth of The dilution rate is a constant, and the economic coefficients for the formation of lactic and acetic acids can be found directly from experimental data. However, the analytical solution of Equation (6) is difficult; therefore, to search for a numerical solution, the system was transformed into the integral form of sequentially calculated equations.Here, The bee colony method was used to determine the equation constants ,42.RMSE) was selected as the criterion for the determination of the optimal values of constants.The root-mean-square error .Taking into account the nature of the growth curves of Bacillus is based on the formation of metabolites by Bifidobacterium, which reduces the specific growth rate. In contrast to static fermentation, in continuous cultivation at a low flow rate, substrate limitation cannot be ruled out, as in the case of Bifidobacterium. Previously, the absence of β-fructofuranosidase in the strain Bacillus cereus ATCC 9634 was shown [Bifidobacterium. It is known that representatives of the species Bacillus cereus are capable of degradation of a number of amino acids  [α(t)). Thus, to calculate the specific growth rate of Bacillus, the following formula is proposed:Bacillus, α(t) is the coefficient for taking into account the lag phase, Bacillus (mg/mL), Bacillus growth-limiting amino acids (mg/mL), and Bacillus growth-limiting amino acids (mg/mL).As in a previous static model , it was as shown , excludie, etc.) , which cA and B are empirical constants that determine the steepness of the sigmoid, and To calculate the lag phase coefficient, it is proposed to use a sigmoidal empirical functionBacillus growth in a mixed culture and the patterns presented above, it can be assumed that the duration of the lag phase depends on the concentration of lactic and acetic acids at the time of contamination (see in the results). However, it is difficult to determine the explicit nature of this dependence, and the literature data on this issue are extremely scarce. Therefore, the below polynomial quadratic equation is proposed. The calculation of the coefficients of this equation based on experimental data using the least squares method allowed obtaining the following equation:Taking into account the characteristics of t = 0.1 h, as highlighted before.The solution of the equations and determination of the constants were carried out using an iteration method with ΔBifidobacterium count, LA concentration, and AA concentration in the monoculture model and Bacillus count in the coculture model were calculated to demonstrate the accuracy of the predictions as follows:Bifidobacterium count , and The mean relative errors for p < 0.05) among the steady states (stationary phases) two-way ANOVA (for time and experiment conditions factors) with post hoc Tukey honestly significant difference (HSD) test was performed. The samples (subsets) of means log(CFU/mL) for stationary phase points of Bacillus monoculture and Bacillus coculture with Bifidobacterium as well as for the Bifidobacterium monoculture were compared. The MatLab software was applied.Each experimental point is presented as the mean ± SD of three repetitions. Changes in data were assessed among different experiments using one-way repeated measure analysis of variance (ANOVA). Additionally, to assess the significant differences  lower than that at a concentration of 7 g/L or more . This made it possible to calculate the values of the yields of metabolite production from the consumed substrate. Moreover, the sum of the yields was close to 1. Thus, the OF was completely spent on the energy needs of Bifidobacterium.In all experiments, the complete consumption of the carbohydrate substrate was observed by the stationary stage. The residual concentrations of OF homologs  for feed concentrations of 7 and 12 g/L are given in Bifidobacterium in the microbial community with acceptable accuracy  difference was noted in the stationary count of Bacillus in the control experiment (monoculture) and in the experiments with the inhibitory effect of Bacillus (p < 0.05) for all OF concentrations in culture experiments. Thus, the influence of Bifidobacterium on the stationary value of Bacillus count is obvious.A significant (Bacillus . At the Bacillus inoculation) to reaching a steady state of Bacillus cell count due to differences in the growth lag duration and specific growth rate in the log phase ) were first determined to calculate the growth delay time.p < 0.05). Other parameters of the model (Equations (9)–(11)) were determined numerically, enabling predictions with low error for all coculture experiments , since their combination determines the duration before the pathogen reaches the maximal count. It can be assumed that a longer time interval increases the chances for the microbiota and the host organism to prevent the disease.A correction factor for modeling the lag phase was previously introduced by Baranyi and Roberts . They alBifidobacterium longum and Lactobacillus fermentum) and prebiotics  on the elderly fecal microbiota [The effect of probiotics (crobiota , as wellcrobiota , was preBifidobacterium and the outcome of bacterial infection under conditions simulating the distal intestine at various doses of the prebiotic substance administered. The concentration of carbohydrates strictly determined the production of metabolites, but the limitation of Bifidobacterium growth was observed only at extremely low values. Significant differences in the growth delay time and specific growth rate of Bacillus were established depending on the concentration of lactic and acetic acids at the contamination time. Mathematical models based on kinetic laws were developed to predict the behavior of individual members of the intestinal microbial community. Although the considered model cannot give definitive answers regarding the outcome of intestinal infection in vivo, a number of the obtained patterns are important for understanding key events. In the future, it seems promising to test the model in a three-stage continuous system with fecal culture.The study determined the main patterns of development of


Satisfactory brain relaxation is essential in neurosurgery. Desflurane anesthesia and propofol-based total intravenous anesthesia (TIVA) have different effects on cerebral hemodynamics, potentially contributing to discrepant brain relaxation. The purpose of this study was to compare the effects of desflurane and TIVA on brain relaxation in patients undergoing craniotomy for supratentorial tumors.In this randomized, controlled study, we enrolled patients aged 18–60 years, with ASA I–III, who were scheduled to undergo elective craniotomy for supratentorial tumors. Patients were randomly assigned in a 1:1 ratio to receive desflurane anesthesia or TIVA. The primary outcome was the proportion of satisfactory brain relaxation. Secondary outcomes included emergence and extubation times, recovery of cognitive function and postoperative complications.P = 0.675). Patients assigned to the desflurane group had shorter emergence  and extubation times , and better recovery of cognitive function at 15 min after extubation , but experienced increased postoperative nausea and vomiting (PONV) (16 [29%] vs. 6 [11%] P = 0.017) and tachycardia  during recovery.Of 369 patients who were assessed for eligibility, 111 were randomized and 110 were included in the modified intention-to-treat analysis (55 in the desflurane group and 55 in the TIVA group). The proportion of satisfactory brain relaxation was similar between the two groups: 69% in the desflurane group and 73% in the TIVA group . Date of registration: December 31, 2020.The online version contains supplementary material available at 10.1186/s12871-023-01970-z. Satisfactory brain relaxation is essential in neurosurgery for sufficient surgical exposure and minimizing the damage to normal brain tissue . IntravePropofol-based total intravenous anesthesia (TIVA) has been widely accepted in neurosurgery due to the capacity of decreasing intracranial pressure (ICP) by reducing cerebral blood flow (CBF) and cerebral blood volume (CBV) . On the To our knowledge, there are few clinical trials designed to evaluate desflurane anesthesia and TIVA on brain relaxation during craniotomy. Most did not take brain relaxation as a primary endpoint and failed to fully address various factors that may influence brain relaxation, such as the use of mannitol , 11. AlsTherefore, we conducted this randomized controlled trial to test the difference between desflurane anesthesia and TIVA in providing brain relaxation in patients undergoing elective craniotomy without severe intracranial hypertension.This was a single-center, randomized, controlled, patient and outcome assessor-blinded trial. Patients were consecutively recruited from Beijing Tiantan Hospital, Capital Medical University from January 2021 to August 2021. Ethical approval for this study (KY2020-150–02) was provided by the Institutional Review Board of Beijing Tiantan Hospital, Capital Medical University, Beijing, China on January 17, 2021, and written informed consent was obtained from all patients. The trial was registered before patient enrollment at clinicaltrials.gov . The report follows the guideline for reporting parallel group randomized Consolidated Standards of Reporting Trials (CONSORT) 2010.2; patients scheduled for retaining tracheal intubation in postoperative; and patients who were unable to comprehend and cooperate with the examination.We enrolled patients between 18 and 60 years of age who had an American Society of Anesthesiologists (ASA) physical status of I to III and were scheduled to undergo craniotomy for supratentorial tumors with general anesthesia. Exclusion criteria were as follows: patients with preoperative brain imaging  with midline shifts over 5 mm ; patientWe randomly assigned patients in a 1:1 ratio to the desflurane group or TIVA group. The randomization sequence was previously computer-generated and preserved in sealed opaque envelopes. The allocation was concealed until the day of surgery. Patients, the outcome assessors and the nursing team were blinded to group assignments. The attending anesthesiologists were aware of group assignments owing to the nature of the intervention.2), the bispectral index (BIS), nasopharyngeal temperature and urine output. An artery catheter was inserted for invasive blood pressure monitoring and blood sampling.After entering the operating room, all patients received standard ASA monitors. Intraoperative monitoring included electrocardiography (ECG), noninvasive blood pressure, pulse oxygen saturation, end-tidal carbon dioxide (ETCO2: 30–35 mmHg). Dexamethasone (5 mg) and ondansetron (8 mg) were administered after induction to prevent postoperative nausea and vomiting (PONV).All patients were premedicated with 0.05 mg/kg of midazolam intravenously 15 min before anesthesia induction in the operating room. After preoxygenation, anesthesia was induced with 0.3–0.5 µg/kg of sufentanil, 1–3 mg/kg of propofol, and 0.2 mg/kg of cisatracurium. After tracheal intubation, mechanical ventilation was established with a tidal volume of 6–8 ml/kg, a fraction of inhaled oxygen of 60%, a fresh flow of 1 L/min in a semi-closed circuit, and the ventilatory frequency was adjusted between 12–15/min to maintain mild hyperventilation  was given to alleviate potential stress responses when the headpins were placed and a scalp incision was performed. The last sufentanil bolus (0.1 µg/kg) was added when suturing dura mater . Total remifentanil consumption was significantly lower in the desflurane group .Intraoperative factors that may affect brain relaxation were well balanced between the two groups except for MAP Table . PatientP = 0.675) (Table P = 0.619). Univariate and multivariate analysis did not show a significant effect of the anesthesia regimen on brain relaxation (Table P = 0.002) and occipital tumors  were independent predictors for unsatisfactory brain relaxation , . In addition, patients assigned to the desflurane group had higher median scores of SOMCT at 15 min after extubation  During the recovery period, patients assigned to the desflurane group experienced more tachycardia  and PONV  The incidence of hypertension and agitation did not differ between the two groups.The emergence time and extubation time in the desflurane group were shorter than those in the TIVA group  is a powerful modulator of cerebral vasomotor tone, and hypocapnia leads to cerebral vasoconstriction [2 of 30 to 35 mmHg) was maintained during surgery following the clinical management routine. Consequently, cerebral vasoconstriction secondary to hypocapnia may mask the direct vasodilatation effect of desflurane. Moreover, in our study, the cerebral hemodynamic effect of desflurane was further complicated by the significant decrease in MAP. It cannot be ignored that similar brain relaxation may occur as a consequence of a decrease in cerebral perfusion pressure. Lastly, fluid balance is a crucial factor affecting brain relaxation, and fluid overload can exacerbate cerebral edema. Our study used uniform fluid management criteria, and the results showed that the fluid input and output were comparable between the two groups at dural opening. Therefore, the interference of fluid balance on brain relaxation assessment was well controlled in our study.Multiple factors may account for our major finding. First, the cerebral vasodilation effect of desflurane is dose-dependent. Low-dose desflurane decreases global CBF by suppressing cerebral metabolism. As the concentration increases, the direct vasodilation effect begins to dominate and may increase CBF, while these effects were mainly observed at concentrations of 1.0 MAC and above . In our triction . In our The multivariate analysis revealed that peritumoral edema is associated with unsatisfactory brain relaxation, which is consistent with previous findings , 23. MorThe present study also found that, compared with TIVA, desflurane anesthesia provides patients with faster emergence and better recovery of cognitive function. In clinical practice, rapid recovery is desirable in neurosurgery because it allows for early neurological assessment and prompt detection of potential complications, such as hematoma formation, acute cerebral infarction, and neurological deficits. This contributes to rapid diagnosis and intervention and may improve patients’ clinical outcomes .Recovery complications were similar between the two groups, except for PONV and tachycardia. Patients assigned to the desflurane group experienced more PONV than those in the TIVA group even though we administered 5 mg of dexamethasone combined with 8 mg of ondansetron to prevent PONV. A recent review suggested that 8 mg of dexamethasone may significantly enhance the antiemetic effect, which could be tested in future studies . In addiOur study has several limitations. First, we did not supplement any objective measures to evaluate brain relaxation, such as subdural pressure and cerebrospinal fluid pressure monitoring, but only a subjective evaluation by the neurosurgeons. However, the standardized 4-point scale is the most practical and accessible measurement to evaluate brain relaxation, and it has been widely applied in many clinical studies , 26–29. In conclusion, among patients undergoing elective craniotomy without severe intracranial hypertension, desflurane anesthesia and TIVA provide similar brain relaxation assessed by the neurosurgeons using a 4-point scale. Desflurane anesthesia provides faster recovery but is associated with increased PONV and tachycardia during the recovery period. Therefore, we should fully balance the strengths and weaknesses of desflurane in clinical practice and optimize the management strategy to benefit patients undergoing neurosurgery.Additional file 1:Figure 1. Jpg Intraoperative Mean Arterial Pressure. Differences in the intraoperative MAP values between the groups were evaluated using RM-ANOVA (P = 0.012). T0, before anesthesia induction; T1, 1 hour after anesthesia induction; T2, dura opening; T3, 2 hours after anesthesia induction; T4, at the end of surgery; T5, emergence. Abbreviations: MAP, mean arterial pressure; RM-ANOVA, repeated-measures analysis of varianceAdditional file 2:Table 1. Steinhoff classification.Additional file 3:Table 2. Brain relaxation 4-point scale.Additional file 4:Table 3. Short Orientation Memory Concentration Test.Additional file 5: Table 4. Univariate Logistic Regression Analysis of Satisfactory Brain Relaxation.