The relationship between IgG4-related disease (IgG4-RD) and the risk of malignancy is still controversial. This article focused on assessing the risk of cancer in patients with IgG4-RD by meta-analysis.P value < 0.05 indicated the existence of publication bias.We conducted a systematic review of the literature and meta-analysis characterizing the associated risk of overall malignancy and four site-specific malignancies  in patients with IgG4-RD. A search from 2003 to 2020 was performed using specified terms from PubMed, Embase, Web of Science and SinoMed. Random-effects model analysis was used to pool standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). Subgroup and sensitivity analyses were conducted to clarify the heterogeneity of the included studies. Begg’s funnel plot and Egger’s linear regression test were used to evaluate the bias of the meta-analysis. A A total of 10 studies were included in the article. The overall SIR estimates suggested an increased risk of overall cancer in IgG4-RD patients (SIR 2.57 95% CI 1.72–3.84) compared with the general population. The specific SIRs for pancreas and lymphoma were higher than those of the general population in IgG4-RD patients . No significant associations were revealed in respiratory and gastric cancer . Four studies were found to be the major sources of heterogeneity by sensitivity analysis. There was no evidence of publication bias via Egger’s test.Compared with the general population, patients with IgG4-RD appear to have a higher risk of overall cancer, especially pancreatic and lymphoma. The risk of lung and gastric cancer was not different between IgG4-RD patients and the general population.The online version contains supplementary material available at 10.1186/s13075-021-02652-2. IgG4-related disease (IgG4-RD), featuring dense lymphoplasmacytic IgG4+ plasma cells, storiform fibrosis and obliterative phlebitis in histopathology, is a chronic fibroinflammatory autoimmune disease with multisystemic involvement. It is crucial to differentiate malignant disease from IgG4-RD for the application of glucocorticoids, the first-line treatment for IgG4-RD.The risk of malignancies in patients with IgG4-RD has not been clarified. There are differing opinions on this issue. It should be noted that with ongoing further research, the initiation of immunomodulatory treatment and biologic agents has a potential therapeutic risk of increasing the incidence of malignancy by altering the normal function of immunosurveillance in addition to acting as an effective therapy in IgG4-RD patients , 2. ThusTo date, there has been no meta-analysis evaluating the risk of malignancy in IgG4-RD. In this article, we review the reported data on the incidence of malignancy and perform a systematic review and meta-analysis to assess the risk of malignant disease.To identify studies characterizing the risk of malignancy in patients with IgG4-RD compared with the general population, a search of PubMed, Embase, Web of Science and SinoMed for literature in English published between 2003 and 2020 was conducted using the following specified search terms: “IgG4-Associated Autoimmune Disease”, “IgG4-Related Disease”, “Autoimmune related systemic disease”, “IgG4 Related Disease” and “Autoimmune Pancreatitis” combined with “Cancer”, “Tumor”, “Malignancy” and “Carcinoma”. The inclusion criteria were as follows: (1) observational-type study design ; (2) more than 100 patients; (3) standardized incidence ratio (SIR) and 95% confidence interval (CI) reported or calculated with information from the literature; and (4) the diagnosis of IgG4-RD was in accordance with the comprehensive diagnostic criteria or fulfilled the specific organ diagnostic criteria. Cancer outcomes, diagnosed concurrently or after the diagnosis of IgG4-RD, were assessed using medical records and reliable radiographic or histological findings. The exclusion criteria were as follows: (1) reviews, case reports, and conference abstracts and (2) a lack of overall SIR and confidence intervals or ambiguous data that were unavailable for calculating the SIR.Two investigators independently assessed the quality of the selected studies and extracted the original literature data, including author, country, calendar period, study type, comparison population, number of patients with IgG4-RD, observed and expected cancer cases, diagnostic criteria, adjusted factors, length of follow-up, SIR and 95% CI data. The Newcastle-Ottawa Scale (NOS) was applied to evaluate the quality of the study, where a score of 5 or less was classified as low quality. Disagreements were resolved through discussion and consensus and if necessary, turning to the third investigator for a final decision.I2 test. I2 values were used to quantify heterogeneity at three levels: low (<50%), moderate (50–75%), and high (≥ 75%). If significant heterogeneity (P<0.05 or I2>50%), the random-effects model was applied. Otherwise, the fixed-effects model was utilized. Subgroup and sensitivity analyses were performed to explore the potential sources of heterogeneity. Publication bias was assessed via Begg’s funnel plot and Egger’s linear regression test. All statistical analyses were performed using Stata 12.0 software.The association between IgG4-RD and various cancers was analysed based on available data, and the pooled SIRs with 95% CIs were applied to evaluate its efficacy. SIRs with 95% CIs for overall cancer and organ-specific cancer risks were pooled only when data from two or more studies were available. In situations in which SIRs were not reported, they were calculated from the numbers of observed and expected malignancies , and the 95% CI was determined assuming that the frequency of observed cases followed a Poisson distribution. Heterogeneity was assessed by means of the chi-square test and A total of 4756 articles were identified according to the search criteria, and 1730 publications were excluded for duplication. A total of 2941 studies were excluded based on the abstract and title. Through full-text evaluations, a total of 10 studies met the inclusion criteria. A flow diagram for the retrieval and inclusion of studies is shown in Fig. All the studies reported the overall SIRs for the malignancy. Only 4 articles –6 calculI2 = 74.1%, P <0.01). Significant increases were observed in the riskof cancer of the pancreas . A forest plot is shown in Fig. I2 value was reduced to 0% with a P value > 0.05, which strongly indicated the heterogeneity resulting from these studies.To further understand the source of heterogeneity, a subgroup analysis Table , Fig. 5 P value for Begg’s test was 0.049, and the P value for Egger’s test was 0.056 (>0.05). In view of the numbers of included studies, the statistical performance was more sensitive in the latter [P value >0.05, which meant that there was no evidence of publication bias in the meta-analysis.A sensitivity analysis was performed to assess the stability of the meta-analysis of the overall risk of malignancy. When any single study was excluded, the corresponding pooled SIRs were not substantially altered. Statistically similar results indicated the stability of the meta-analysis. The e latter . Egger’sOur meta-analysis revealed an association between IgG4-RD and increased cancer risk compared with the general population. The outcome successfully shed light on IgG4-RD increasing the risks of overall cancer, particularly of cancer of the pancreas and lymphoma. In addition, no significant associations were discovered between IgG4-RD and the lung or stomach. Four studies , 8–10 laWe detected a significantly increased risk of pancreatic cancer in IgG4-RD patients compared with the general population. Generally, chronic pancreatitis is a risk factor for developing pancreatic cancer . It is bLung cancer complicated with IgG4-RD has been reported in recent years , 23. TheHelicobacter pylori infection might increase the risk of developing gastric cancer via the immune cross-response in IgG4-RD patients [It is also interesting that the pooled SIR for gastric cancer in IgG4-RD did not show an increased risk compared with the general population. However, in the study of Shiokawa et al., gastric cancers accounted for the highest proportion among all IgG4-RD-CA patients. In a meta-analysis focusing on the risk of gastric cancer in autoimmune diseases, IgG4-RD was associated with an increased risk of gastric cancer, with a relative risk of 1.69 (95% CI 1.00–2.87) . Helicobpatients . The relI2 = 89.5%, P <0.01). Previous studies suggested that the clonal expansion of IgG4+ plasma cells against a background of IgG4-RD chronic inflammation may participate in the progression of mucosa-associated lymphoid tissue (MALT) production [The increased risk of nonsolid tumours, such as lymphoma and leukaemia, was also a large part of the investigation among IgG4-RD-CA patients. Our meta-analysis presented a significant association between lymphoma and IgG4-RD. However, the high heterogeneity of the combined SIR reminded us to interpret the results with caution (oduction , 30. A soduction  from Poloduction  and Hiraoduction  showed tThe concrete mechanism between IgG4-RD and malignant disease is still inconclusive. The possible hypotheses include chronic inflammatory stimulation and dysfunction of the immune system. Inflammation increases the risk of cancer and has been elucidated in several diseases . T helpeSubgroup analysis failed to clearly determine the possible source of heterogeneity, while the sensitivity analysis discovered that four articles were responsible for the heterogeneity of the meta-analysis. After further analysing these articles, we considered that the heterogeneity may be explained by the following study limitations. First, the follow-up period of the study from Korea  was onlyThe primary advantage of this study was that we used the SIR to evaluate the relative risk of IgG4-RD compared with the general population, which deserved more attention for the diagnosis and management of IgG4-RD patients. Furthermore, pancreatic cancer and lymphoma were found to be more frequently seen in IgG4-RD-CA patients. However, the high heterogeneity in the combined SIR of lymphoma indicated that it should be interpreted with caution.However, the limitations of our study are obvious. First, most of the included studies were retrospectively retrieved from records or national databases, the potential deviation could not be ignored, and there was moderate heterogeneity among the included studies. However, from the results of the sensitivity analysis, the heterogeneity had no substantial influence on the overall pooled SIR. Second, the confounding factors were not fully standardized, especially in terms of the incidence of organ-specific cancer. Third, more included studies and larger sample sizes are needed to improve the meta-analysis results. Fourth, most of the follow-up periods in the included studies were insufficient to fully assess the risk of cancer. Fifth, the lack of uniform diagnostic criteria for IgG4-RD in the included studies weakened the statistical effect. Sixth, not all articles reported organ-specific cancer SIRs.Taken together, IgG4-RD increases the risk of malignancy compared with the general population. Pancreatic cancer and lymphoma are associated with a high incidence rate in IgG4-RD patients according to the present data. Therefore, it is of great importance to screen for cancer in the management and diagnosis of IgG4-RD. However, we should be cautious when interpreting the results since most of the present studies are observational and the follow-up periods are relatively short for completely assessing the incidence rate of cancer. The concrete mechanism of IgG4-RD in developing malignant disease is unclear. Further higher-quality studies are needed to verify and elucidate the relationship between IgG4-RD and tumours.Additional file 1.Additional file 2.


Enterobacteriaceae and Enterococcaceae abundance in endotracheal and perineal microbiota for those administered 3GC compared to the control group. Culture-based analyses did not identify any significant changes in the prevalence of specific pathogenic or antibiotic-resistant bacteria. Exposure to clinical antibiotics has previously been linked to reduced microbiota diversity and increased antimicrobial resistance, but our results indicate that these effects may not be immediately apparent after short-term real-world exposures.Effective implementation of antibiotic stewardship, especially in critical care, is limited by a lack of direct comparative investigations on how different antibiotics impact the microbiota and antibiotic resistance rates. We investigated the impact of two commonly used antibiotics, third-generation cephalosporins (3GC) and piperacillin/tazobactam (TZP) on the endotracheal, perineal and faecal microbiota of intensive care patients in Australia. Patients exposed to either 3GC, TZP, or no β-lactams (control group) were sampled over time and 16S rRNA amplicon sequencing was performed to examine microbiota diversity and composition. While neither treatment significantly affected diversity, numerous changes to microbiota composition were associated with each treatment. The shifts in microbiota composition associated with 3GC exposure differed from those observed with TZP, consistent with previous reports in animal models. This included a significant increase in  However, the magnitude of these changes is not uniform among individuals due to large interpersonal variation in baseline microbiota composition5. Antibiotics are heavily used in intensive care units (ICUs) and timely antibiotic intervention, immediately upon presentation, saves lives6. Antimicrobial exposure, however, can have long-lasting detrimental impacts on gut microbiota health, including reduced resistance against subsequent infections9, with recovery from dysbiosis dependent on the type of antibiotic treatment received12. There is therefore urgent need to define ways to preserve microbiota integrity in ICU patients, including the use of probiotics and selective digestive tract decontamination to reduce microbiota dysbiosis15.The human gut microbiota plays an integral role in host metabolic functions and immunity. Intensive care has been associated with substantial changes in the intestinal microbiota of patients, including reduced microbial diversity, altered composition with a propensity for expansion of pathobionts such as Proteobacteria, and increased levels of antibiotic resistance17. Antibiotic regimens in critical care typically include broad-spectrum drugs targeting the main nosocomial pathogens19, and associated colonisation by antibiotic-resistant bacteria and perturbations of gut microbiota composition and functions are largely predictable21. However, different antibiotics vary in the spectrum of activity, route of administration, pharmacokinetics (distribution and elimination in the host) and pharmacodynamics (interactions between drug and pathogen)23. Some antibiotics may be more harmful to the microbiota than others22.Antibiotic stewardship programs aim to reduce unnecessary and inappropriate antimicrobial use through optimal therapeutic choices24. They have very similar pharmacokinetic and pharmacodynamic characteristics and spectra of activity against medically important pathogens but data from animal models25 and accumulated clinical experience suggest different ecological outcomes27. Both antibiotic classes are associated with an increased presence of antibiotic-resistant Enterobacteriaceae, staphylococci, Clostridioides difficile and Pseudomonas aeruginosa in the microbiota30 but 3GC has been shown to result in poorer microbiota recovery and longer-lasting changes31 and antibiotic guidelines often recommend restricted use due to concerns linked to ‘collateral damage’ to the commensal microbiota32. Despite this, there is a lack of direct comparative data. We, therefore, examined the differential impact of 3GC and TZP on the endotracheal, perineal and faecal microbiota of ICU patients in two hospitals in Sydney, Australia.Third-generation cephalosporins  and penicillin/β-lactamase inhibitor combinations  are broad-spectrum antimicrobials commonly used in critical careThe impact of administrating 3GC or TZP on the endotracheal, perineal and faecal microbiota composition was examined using 16S rRNA amplicon sequencing. A total of 222 samples were collected over time (from 24 h to 11 days after ICU admission) from patients receiving either 3GC, TZP or no β-lactams (control group), details on the number of samples collected per treatment group and patient are provided in Supplementary Table 33. The exact microbial composition in each body site varied significantly between individuals  or may be indicative of microbiota changes in the early stages of antibiotic therapy. Limitations inherent to real-world ICU studies, including a lack of samples collected before illness or antibiotic administration and the variable availability of some samples  add to difficulties in interpretation.Samples collected within 48 h of antibiotic administration (for 3GC and TZP groups) or ICU admission (for control group) were considered representative of the initial microbiota of each patient. This classification was based on previous publications where no significant change in the gut microbiota or antibiotic resistance was observed within the first 48 h of antibiotic exposureStaphylococcaceae, in 13 out of 24 samples collected within the first 48 h  or antibiotic exposure (3GC and TZP).The initial composition of the perineal microbiota showed a simpler community composition with > 90% of taxa belonging to a single family, 41, indicating a generally diverse overall microbiota community. Compared to the control group, there was no significant difference in microbiota alpha diversity in those receiving either 3GC or TZP. Antimicrobial therapy, especially with broad-spectrum antibiotics, has previously been associated with a lower alpha diversity in the gut microbiota42. In this study, however, neither antibiotic regimen significantly altered overall microbial alpha-diversity in any of the three body sites, suggesting that the use of powerful broad-spectrum β-lactams does not immediately result in a strong decline in microbiota diversity relative to other ICU patients that did not receive these antibiotics. While the observed lack of changes in the overall microbiota community structure and alpha diversity could be due to exposure of the control group to antibiotics other than 3GC and TZP or to antibiotic-exposed microbiota in the ICU environment more generally, this is an inherent challenge when conducting a human clinical trial in a critical care setting.The impact of the two antibiotic regimens on the overall microbiota community structure was examined using multi-dimensional scaling (MDS) plots based on Bray–Curtis similarity metrics of the operational taxonomic unit (OTU) abundance. These revealed no statistically significant difference in the overall community structure of the initial microbiota (< 48 h) between the three groups and neither antibiotic treatment resulted in a significant shift in the overall microbiota community in any of the three body sites after 48 h compared that in the control group  but this was statistically significant only for 3GC in this study  and in Bacteroides compared to the control group, with relative reductions in the abundance of OTUs within Enterococcus and Staphylococcus genera. These results demonstrate a clear and distinct impact of short-term administration of 3GC and TZP on the endotracheal, perineal and faecal microbiota of critically ill patients. Sampling microbiota following critical care will be a useful extension to the current study in elucidating associations between microbiota recovery following intensive care and antibiotic exposure.LEfSe analyses conducted at the OTU level showed significant variations after both antibiotic exposures Table . While m3, but the culturable microbes in this study were not significantly enriched for major aerobic pathogens  and changes in their antibiotic resistance phenotypes, we performed culture-based microbiological analysis (on selective media) on samples from a subset of patients for whom faeces were collected both at ICU admission (< 48 h) and after antibiotic administration (> 48 h). As expected for such powerful broad-spectrum antibiotics, particularly in endotracheal and perineal sites, 40% of samples failed to yield any detectable bacterial growth after overnight aerobic incubation on specific isolation media (Supplementary Table Our results demonstrate no significant change in the presence of specific pathogens and their antibiotic resistance after short-term exposure (< 11 days) to 3GC or TZP, but this examination was limited to specific culturable bacteria and the number of samples per treatment group was low. While the average length of stay is typically less than a week in ICUs of this type, the impact of longer-term exposure to these antibiotics would be a useful future extension to this study. Future larger scale studies with quantitative approaches to detect pathogens and experimental designs to analyse the gut resistome are important in obtaining a comprehensive overview of the impact of 3GC and TZP on the relative abundance of opportunistic pathogens and levels of antibiotic resistance, respectively, and are currently in progress.Enterobacteriaceae and Enterococcaceae, which include some of the main nosocomial antimicrobial-resistant pathogens46, was significantly higher in the endotracheal and perineal microbiota only after 3GC exposure, while TZP treatment was associated with an increase in the abundance of bacteria generally considered as commensals, particularly in the perineal microbiota. TZP treatment was associated with an increase in relative abundance of Enterococcaceae in the faecal microbiota, demonstrating a clear body site-specific impact of the two antibiotic regimens.Administration of either of two broad-spectrum antibiotics, 3GC or TZP, resulted in significant changes in the endotracheal, perineal and faecal microbiota of ICU patients. The relative abundance of the 47. Despite the small sample size and the complexity of these responses in inherently dysbiotic environments, our ‘real world’ data support such clinical observations, provide direct information on how these different antibiotic treatments affect the microbiota and underline the value of larger scale studies.Third-generation cephalosporins are widely believed to be more injurious to the microbiota than many other antibiotics with comparable safety and efficacy profiles and clinical indications in critically ill patients. Consequently, restriction of their use is a major goal of antibiotic stewardship programs and is associated with reduced costs and reduced rates of infection due to resistant pathogens, with the benefits being most marked in intensive care settingsThe target population for this study included critically ill, mechanically ventilated patients who had not received the specific antibiotics (3GC or TZP) for at least two weeks prior to ICU admission. The three study cohorts were: (1) patients receiving a third-generation cephalosporin ; (2) patients receiving piperacillin/tazobactam (TZP); Tazocin); and (3) patients who were critically ill and mechanically ventilated but did not receive either TZP or 3GC during ICU stay (control group). The latter group was recruited from patients presenting with trauma, acute cardiac or cerebral ischemic events, severe asthma or status epilepticus, and who had not received antibiotics in the previous two weeks.Specimens were collected over a two-year time span (2015–2017) at two hospitals in western Sydney (Westmead and Nepean ICUs), Australia. Perineal swabs and endotracheal aspirates were collected from patients as a part of routine clinical praxis on day 1 (24 h from the start of antibiotic treatment), day 3 (72 h from the start of antibiotic treatments), day 5 and day 7 (if the patient was still in the ICU). Faecal specimens were collected each time a patient passed a bowel motion. Antibiotic effects were determined by comparison of samples prior to (< 48 h) and after (> 48 h) antibiotic treatment. Faecal samples were immediately frozen at − 20 °C, and endotracheal aspirates and perineal swabs were refrigerated (2–8 °C). After collection at the approved clinical sites, the specimens were transferred to the laboratories for further analysis.49. Sequencing of the amplicons was performed on an Illumina MiSeq v2 platform (2 × 250 bp). Library preparation and sequencing were performed at the Ramaciotti Centre for Genomics .Total microbial DNA was extracted from endotracheal aspirates, perineal swabs and faeces using a MoBio PowerSoil DNA extraction kit  according to the manufacturer’s instructions. The V4 variable region of the 16S rRNA genes in extracted DNA was amplified using the 515F-806R primer pair with custom barcodes for Illumina MiSeq sequencing50. Full length and high quality (− q 19 and with other default parameters) reads were used to determine operational taxonomic units (OTUs) at 97% similarity using an open-reference protocol against the Greengenes database (version 13_8)51. A total of 19,638,026 reads  were obtained for a total of 231 samples prior to filtering out OTUs with less than 0.005% reads. Reads per sample were rarefied to 10,387 reads, nine random samples failed to meet this requirement and were eliminated from further analysis. A total of 222 samples were retained and used for further statistical analysis.Demultiplexed raw sequence data were processed using Quantitative Insights Into Microbial Ecology (QIIME) software (version 1.9.1)All statistical analyses on the microbiota data were performed using rarefied and filtered OTUs.52 (default parameters were used unless otherwise stated). Overall microbiota community structure was visualised using multi-dimensional scaling (MDS) plots based on Bray–Curtis similarity metrics of the abundance of the OTUs. Permutational Multivariate Analysis of Variance (PERMANOVA) tests with 9999 permutations were conducted to investigate statistical significance of differences in the microbial community structure between treatments. The Shannon diversity and Simpson’s evenness indices per sample were also determined using PRIMER-7. Statistical significance of the differences in the alpha diversity indices was determined through Tukey’s multiple comparison tests with Geisser-Greenhouse correction using GraphPad Prism .The OTU abundances (Log (x + 1) transformed) were used for analysis using PRIMER-7 software package53. Separate LEfSe analyses were conducted on samples collected within and after 48 h of antibiotic exposure to determine the differences in the initial microbiota and the impact of antibiotic exposure, respectively. All LEfSe analyses were conducted using antibiotic treatment groups as the subject (no subclasses) and all other default parameters, including Kruskal–Wallis test among classes (P < 0.05), Wilcoxon test between classes (P < 0.01) and the threshold on the logarithmetic LDA score for discriminative features > 2.0. Detailed information on the number of patients included in each analysis are provided in Supplementary Table P values) were conducted through Benjamini and Hochberg method using GraphPad Prism . Significant differences in the abundance of bacterial families and OTUs that passed an adjusted P value of 0.05 are presented.Bacterial families and OTUs with significantly different abundances between the control group and each antibiotic treatment were identified using Linear discriminant analysis Effect Size  analysisg; 10 min), supernatants discarded, and pellets washed in saline and then re-suspended in 1 mL 20% glycerol for long term storage at − 80 °C. Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa, pathogenic species known to be highly abundant in ICU patients under antibiotic treatment3 and predominant Gram-negative enteric bacteria were sub-cultured on species-specific identification media: Brilliance MRSA Agar , Difco Pseudomonas Isolation Agar , and ChromAGAR supplemented with vancomycin , respectively. Isolated enteric colonies identified as potential Escherichia coli (pink colonies) or Klebsiella pneumoniae (blue colonies) were also tested for resistance to extended-spectrum β-lactams by plating on selective media  and LB agar  supplemented with 2 µg/mL cefotaxime). Bacterial isolates (six colonies per sample) from faecal specimens were also screened on a panel of clinically relevant antibiotics  by automated disc-diffusion assay . Statistical analysis of significance (P ≤ 0.05) was performed using McNemar’s test and regression models fitted on the data.Aerobic microbiota was cultured from collected specimens by direct inoculation of 5 mL nutrient broth  and overnight incubation at 37 °C with shaking. Cultures were pelleted by centrifugation  and Westmead (LNRSSA/14/WMEAD/313) hospitals. All methods were performed in accordance with the relevant guidelines and regulations. The study was conducted under a waiver of consent, with the auspices of the above-mentioned Human Research Ethics Committees.Supplementary Information 1.Supplementary Table S1.Supplementary Table S2.Supplementary Table S3.


The demand for animal protein has increased considerably worldwide, especially in China, where large numbers of livestock and poultry are produced. Antibiotics have been widely applied to promote growth and prevent diseases. However, the overuse of antibiotics in animal feed has caused serious environmental and health risks, especially the wide spread of antimicrobial resistance (AMR), which seriously affects animal and human health, food safety, ecosystems, and the sustainable future development of animal protein production. Unfortunately, AMR has already become a worldwide challenge, so international cooperation is becoming more important for combatting it. China’s efforts and determination to restrict antibiotic usage through law enforcement and effective management are of significance. In this review, we address the pollution problems of antibiotics; in particular, the AMR in water, soil, and plants caused by livestock and poultry manure in China. The negative impact of widespread and intensive use of antibiotics in livestock production is discussed. To reduce and mitigate AMR problems, we emphasize in this review the development of antibiotic substitutes for the era of antibiotic prohibition.  With the increasing demand for protein-rich food, global animal production has intensified considerably, especially in developing countries. Antibiotics are widely used in animal husbandry because of their functions in promoting growth and preventing disease. Antibiotics provide benefits, but also cause severe problems to food safety, human health, and the environment, leading to the antimicrobial resistance (AMR) problem . It has http://www.who.int (accessed on 30 March 2021)). For instance, the recent outbreaks of swine influenza, Ebola, and the devastating ongoing Covid-19 pandemic are examples of zoonotic diseases transmitted between animals (including wildlife) and humans. Luckily, many countries have already taken action to reduce the application of antimicrobials in animal production; in particular China, the world’s largest meat consumer. Already in 2016, the Chinese government launched a national pilot program coupled with policy and regulations to decrease unnecessary antimicrobial use [quick fix for the AMR problem, due to its complexity. It is clear that a ban on antibiotic feed additives will directly affect the disease resistance and normal growth cycle of livestock production, thus indirectly increasing the investment costs of livestock and poultry. Hence, there is an urgent need to tackle the AMR threat and find safe and sustainable solutions to ensure the animal protein food supply and protect human, as well as animal, health in the future. This review focuses on pollution by antibiotics and AMR in livestock and poultry manure and countermeasures against this in China, in light of China’s 14th 5-year plan, which was launched recently and recognized the increasing demand for animal protein food supply and security. It is reported that approximately 80% of all antibiotics sold in the United States are sold for use in animal agriculture to boost animal growth and protect them from infections . Moreovebial use . There iThe environmental pollution caused by antibiotics and their ecotoxicological effects has become a major global problem, especially the environmental pollution caused by the abuse of antibiotics in the livestock and poultry industry ,6,7,8, wChina is a large agricultural country, and the livestock and poultry breeding industry has gradually changed from decentralized, to intensive, farming. The use of antibiotics is common, and the antibiotic-related pollution caused by livestock and poultry manure is prominent ,23,24. AIt is estimated that 30–90% of antibiotics are excreted from the body, in the form of parent compounds or main metabolites, along with animal feces or urine . High coTreated or untreated aquaculture wastewater is an important source of river pollution by antibiotics and ARGs. Xu et al.  monitoreIn addition to antibiotics, a large number of ARGs were detected in the river. For example, the detection rate of sulfonamide resistance genes (sul1 and sul2) in Tianjin Haihe River was 100%, and their abundance was high ; there wwww.who.int (accessed on 30 March 2021)).The environmental risks of water pollution caused by antibiotics are now in focus and need the attention of the entire society. Antibiotics have been widely found in water, and are eventually absorbed or consumed by aquatic organisms. When antimicrobials are used in aquaculture seafood production, the AMR genes may enter into the food chain and eventually into the human body through seafood consumption. This could cause damage to human health over time and lead to drug resistance, which could have a great impact on the elderly, children, pregnant women, and other groups with weak immunity. Furthermore, because of the long-term enrichment of antimicrobials in water, some bacteria and fungi could acquire multi-drug resistance, and then form “superbugs”. Infections caused by superbugs are a true threat to human and animal health worldwide and can lead, not only to loss of life, but also to a heavy economic burden on the health sector  can accelerate the production of antibiotic-resistant bacteria. Once antibiotic-resistant bacteria are produced, they can spread among animals, which will make animals in large-scale breeding facilities become a huge reservoir of ARGs. The antibiotic resistance of antibiotic-resistant bacteria from animals can be transferred to human beings, which has a great impact on human health. According to results published in the Proceedings of the National Academy of Sciences, 149 unique ARGs have been found in Chinese commercial pig farms, and the levels of some ARGs are 192 to 28,000 times higher than those of the control samples [Previous studies have shown that penicillin, streptomycin, sulfonamides, and other antibiotics cause allergies; chloramphenicol causes regenerative, dysfunctional and hemolytic anemia, thrombocytopenia, and liver injury; tetracyclines cause photosensitivity and gastrointestinal reaction; olaquindox is a gene inducer; furazolidone induces animal carcinogenesis; aminoglycoside antibiotics cause nephrotoxicity; and fluoroquinolone keto antibiotics can cause mitochondrial damage ,62.The harm caused by ARGs is mainly manifested in the resistance of bacteria to antibiotics, which makes these ineffective or reduces their effect. At present, infections caused by antibiotic-resistant bacteria are becoming more common around the world ,64. AccoIn the 1950s, the United States Food and Drug Administration (FDA) approved, for the first time, the addition of antibiotics to feed, and countries around the world began to study the application of antibiotic additives; since the 1960s, countries have begun to use a large number of antibiotic additives in feed. With the development of antibiotic resistance and the intensive use of antibiotics, people have paid more and more attention to the potential harm of antibiotics. Since the 1980s, based on food safety considerations, countries have enforced strict restrictions on the use of antibiotic additives. In 1986, Sweden completely banned the use of antibiotics in animal feed. In January 2006, EU countries completely banned the addition of any antibiotics to feed. In 2010, the U.S. Food and Drug Administration began to call for a gradual ban on the use of “antibiotics with important medical uses” in animal husbandry. The latest revision of the Drug Law of Germany introduced the concept of minimum antibiotic use. Antibiotic monitoring involves 95% of poultry farms and about 90% of pig farms in Germany. In September 2015, the European Union published guidelines on the prudent use of antimicrobial veterinary drugs. The use of antibiotics as feed growth promoters was banned in South Korea in 2011.China attaches great importance to the management of antibiotics. In recent years, with the improved understanding of the hazards of antibiotics, the Ministry of Agriculture of China promulgated a series of announcements, such as the No. 168 notice “the use standard of feed drug additives” which was promulgated in 2001, and announcement No. 193 “list of prohibited veterinary drugs and other compounds in food animals”, which was promulgated in 2002, standardizing the use of antibiotic feed additives. At the end of 2015, the use of lomefloxacin, pefloxacin, ofloxacin, and norfloxacin was prohibited in food animals. In November 2016, regulations were issued to stop the use of colistin sulfate as an feed additive. On 20 April 2018, the state issued a pilot work plan for the reduction of veterinary antimicrobial use (2018–2021). On 10 July 2019, the No. 194 announcement of the Ministry of Agriculture and Rural Areas stipulated that, from 1 January 2020, all kinds of growth promoting drug feed additives, except traditional Chinese medicines, should be withdrawn, veterinary drug manufacturers should stop production, and the importers of veterinary drug agents should stop importing the corresponding veterinary drug products, and at the same time they cancelled the corresponding veterinary drug product approval number and import veterinary drug registration certificate. This marks the withdrawal of 12 growth promoting drug feed additives from the historical stage, and China has officially entered the era of it being “forbidden to add antibiotics to feed”.In recent years, AMR has become a global threat to human and animal health, as well as to the ecosystem and environment. In order to reduce and eventually eliminate the AMR problem in the future, antibiotic substitutes play an important role. More and more antibiotic substitutes have been used to reduce or even replace the use of antibiotics in livestock production .Staphylococcus aureus and promote the formation of intermediates [At present, there are about 4500 kinds of essential oils and other bioactive components extracted from the flowers, seeds, leaves, bark, and fruits of various plants. The main components of essential oils include carvacrol, citronellol, geraniol, eugenol, and thymol . Some esmediates . In addimediates . Howevermediates ,72. Somemediates ,74. GeneCT is a kind of oligomeric or polymerized flavonoid, which is composed of flavane-3-ol. It mainly includes catechin, epicatechin, gallocatechin, and epigallocatechin. CT has antibacterial, antiparasitic, antioxidant, and immunomodulatory activities. CT can be used as a natural substitute for antibiotics in feed . The effMannheimia have been isolated [Phages are predators of bacteria, destroying half of the world’s bacteria every 48 h . As earlisolated ,81. PhagVaccines are widely used to prevent bacterial and viral infections in livestock and poultry, and are currently the most promising alternative to antibiotics. Differently from the therapeutic effect of antibiotics, the most important value of vaccine is prevention, which can not only prevent virus infection but also prevent bacterial infection. Conventional vaccines usually use heat inactivated bacteria or viruses, or active modified and purified components. However, there is a direct effect of vaccination on the clinical status of the host, and therefore, there is a need for vaccination before the clinical response. It is very difficult to develop vaccines against intestinal microorganisms, and only a few vaccines can maintain their efficacy against pathogens in the intestinal environment. At the same time, in order to control the disease, it is necessary to realize whole group vaccination, otherwise the infectious pathogens can continue to spread among the unvaccinated individuals.Probiotics can inhibit pathogens, change metabolism, and regulate immunity . ProbiotAn antimicrobial peptide (AMP) is a kind of polypeptide with a strong antibacterial effect. Antibacterial peptides have the advantages of a broad antibacterial spectrum, immune function, promoting growth, and not easily producing antibiotic resistance. They have a broad application potential in animal husbandry production. Research efforts have been made to identify and characterize AMPs in different organisms, and a large number of AMPs have been reported, even from organisms such as the Arctic cold-water red king crab . The AMPAcidifiers can be divided into organic, inorganic, and compound acidifiers, which can improve the acidity value and enzyme activity of the diet and promote the absorption of nutrients. It was found that adding different levels of acidifier in sow feed can improve sow feed intake and promote piglet growth. Organic acids can reduce the infection rate and spread of Salmonella in pigs. The results of a Limin test showed that adding 1250 mg/kg metabolic organic acids to the diet could promote protein deposition in growing finishing pigs, thus improving their growth performance.Oligosaccharide is the general term for low molecular weight sugars with a straight or branched chain formed by two or more monosaccharides  linked by a glycosidic bond. They have physical and chemical properties such as high temperature resistance, stability, and non-toxicity. At present, functional oligosaccharides are mainly used as feed additives. They can improve the microbial community structure of the digestive tract, improve the immunity of the body, promote the development of the digestive tract, and enhance the digestion and absorption capacity of animals. Dietary chitosan can promote the growth of piglets, improve the intestinal barrier function, and increase the quantity of bifidobacteria and lactic acid bacteria . HasunumWith the restriction of the use of feed antibiotics, there is an opportunity for enterprises and institutions to actively search for technical means and products that can effectively reduce or even replace these. However, the antibacterial efficacy of these substances has limitations. Compared with antibiotics, the mechanisms by which these substitutes inhibit or kill bacteria are still unclear, and their mode of action needs to be further understood.AMR has become a global threat to human and animal health in addition to the negative impact on the ecosystem and environment. Stakeholders’ involvement is essential in order to mitigate the AMR problem. China has made efforts to control AMR spreading by policy enforcement, as well as the participation of the industry and livestock farmers in identifying and using alternative additives replacing antibiotics, as well as effective prevention, management strategy, and diagnosis through the support of veterinary and training courses.There is a need for farmers to realize that the long-term use of antibiotics or abuse of antibiotics will bring irreversible harm to human health and the living environment. The government can regularly organize training on non-resistance breeding; vigorously publicize the harm of antibiotic abuse and the benefits of breeding without antibiotic overuse to large numbers of farmers, changing the farmers’ perception; hire experts to train the framers in breeding, so as to improve their professional skills; establish a non-resistant breeding pilot; and promote non-resistant breeding technology.In the past, environmental hygiene was not considered in agriculture, resulting in poor environmental sanitation, which led to the large-scale infection of livestock. Farms (households) could only use antibiotics to treat them. Therefore, it is necessary to establish ecological breeding areas. At the same time, other related industries should be allocated according to local conditions to form an efficient and pollution-free support engineering system. The development of resources and the ecological balance should be organically combined to reduce the occurrence of livestock diseases. According to a pre-established immunization plan, we should improve the vaccination of livestock and reduce the incidence rate of livestock and poultry diseases . RegularControlling pathogens from the source, improving the health supervision system and biosafety route, and selecting some mature antibiotic substitutes  can improve the economic benefits of agriculture ,98,99. China is a large country for livestock and aquaculture production, and also a significant country for the production and use of veterinary antibiotics. It is an undeniable fact that veterinary antibiotics play an important role in animal husbandry production, the prevention and control of animal diseases, the improvement of breeding production efficiency, and guaranteeing an effective supply of livestock and poultry products. However, for a long time, the irrational use of veterinary antibiotics in Chinese animal husbandry production has led to an increase in the antibiotic resistance rate of animal derived bacteria and the emergence of "super-bacteria"; the residues of veterinary drugs and pesticides in animals aggravate the toxic and side effects of veterinary antibacterial drugs. The residual drugs are discharged into the outside world, polluting the soil and water sources, resulting in the pollution of the ecological environment. This threatens the safety of livestock and aquatic product production and quality, public health, and ecological environment security. Therefore, China has taken positive and decisive measures to ban the use of growth promoting feed drug additives. This is of great practical significance for the transformation and upgrading of Chinese animal husbandry, ensuring the safety of the people’s food and the export trade in livestock and poultry products to the world. In order to tackle the AMR problem, public awareness of the AMR threat, public engagement in mitigating AMR spread, and both basic and advanced medical education and training on the causes of the AMR problem, as well as solutions to reduce and control AM, are essential, and will play a pivotal role in the effective management of AMR globally . We shouThe use of antibiotics and antibiotic resistance is a worldwide challenge, and the research and development of antibiotic substitutes needs to continue. Therefore, international cooperation is becoming more and more important. China needs to work with other countries to cope with the challenges of the post-antibiotic era and develop new antibiotics or antibiotic substitutes, while strictly controlling the use of antibiotics. It is believed that with the joint efforts of the international community, the effective management and sustainable use of antibiotics can be realized.


Pneumocystis pneumonia in gay men were described in CDC’s Morbidity and Mortality Weekly Report. Those cases signaled the start of the AIDS pandemic, which now enters its fifth decade and has to date resulted in more than 75 million HIV infections and 32 million deaths worldwide. UNAIDS estimates that in 2019, 38 million persons were living with HIV, 1.7 million became newly infected, and 690,000 died with HIV disease.In June 1981, five cases of Art AIDS America examined the ongoing influence and impact of the AIDS pandemic on American art. Since the beginning of the HIV/AIDS pandemic, artists―some involved in AIDS activist organizations and others working independently―have applied their talents and skills to create, share, and deliver works that depict messages calling for political action and scientific research, documenting the impact of AIDS among various and diverse communities and groups, and celebrating medical breakthroughs and advances in treating AIDS. In 2016, a traveling exhibition entitled More Time Expected by Lakota artist Thomas Red Owl Haukaas, displayed on this month’s cover. Haukaas conveys both a sense of fluid motion and frozen time in this image, a modern example of Native American ledger art (a genre of narrative drawing or painting on paper or cloth) that developed during the Indian Wars era and continued in the forced relocations of Plains tribes to government reservations from the 1860s through the 1920s. Widespread hunting had depleted buffalo and other game animals that provided hides the tribes traditionally used as canvases for recording events, ceremonies, and exploits. As a result, Native Americans began using paper taken from ledgers and other sources and employing ink, pencils, and watercolors rather than bone or wooden implements dipped in mineral and other natural pigments. Among the more than 125 works featured in that traveling exhibition was In this work, Haukaas shows a group of Native Americans and horses sweeping from right to left across the paper. The figures and horses are crowded, flattened, and overlapping each other. Riders and horses are looking straight ahead and moving in unison toward a destination beyond the edge of the image. The artist carefully depicts his figures of Native Americans dressed in traditional garb and wearing an array of bright colors and patterns. The horses are also stylized and individualized: many are boldly colored, and others are sketched with repeating patterns and rows of stripes. Half of the horses carry either a single rider or a pair of riders, but the other half are riderless, including the cobalt blue horse that draws attention to the center of the image. Art AIDS America in partnership with the Bronx Museum of the Arts, explains how this work is related to HIV/AIDS: “The imagery, specifically the riderless horse, explores the complicated issues of stigma surrounding HIV/AIDS and the Native American experience with the disease. Historically, instances of HIV on the reservation are virtually unmentioned, a silence that only worsens an already high rate of infection. The horse with no rider, often used as a symbol for a warrior who fell in battle, represents individuals on the reservation who have died of AIDS-related causes. By focusing on absence within a group, Haukaas plays to the importance of community and families within these settings.”Michelle Reynolds, Associate Director of Marketing and Communications at the Tacoma Art Museum, which organized In a 2018 interview, Haukaas told writer and editor Emily Withnall, “My pieces are meant for dialogue, for discussion, for thinking about.” Despite the fluidity and motion of his work, the underlying message carried by his portrayal of these riderless horses is the palpable sense of what has been lost. Haukaas, whose works are featured in many museum collections and have been part of numerous exhibitions, does not have formal training in art, and he credits his family and friends for teaching him traditional skills and practices. Known for his talents as a ledger, beadwork, and doll artist, he trained as a psychiatrist. Through this image, Haukaas reconnects with the traditional ledger art form and uses it as a platform to engender thought and discussion about the ongoing medical and social effects of HIV within reservation communities, throughout other marginalized racial and ethnic communities around the world, and in those regions most affected by this ongoing pandemic. As De Cock, Jaffe, and Curran state in their EID article Reflections on 40 Years of AIDS, “Although initially slow, the HIV/AIDS response over the years has been a beacon in global health for respect for individuals and their rights and for health equity. More reflection is required with regard to what the responses to HIV and Ebola have taught us and how they might be relevant to COVID-19 and other future epidemics.”


The construction industry has extensively demanded novel green inhibition strategies for the conservation and protection of carbon steel-reinforced concrete structures. For the first time, the effect of Azadirachta indica leaf extract (Neem) as a potential corrosion inhibitor of carbon steel in reinforced concrete under corrosion in saline simulated media was evaluated. To assess the corrosion inhibition behavior of the Neem natural organic extract, three inorganic commercial inhibitors were tested to compare following the criteria established by Stratful for half-cell potential under a simulated chloride environment. Moreover, the effect of concrete integrity by the Neem treatment was recorded after different temperature conditions, slump, weight alteration, air content, compressive strength, and chloride-ions penetration. The results suggested that the Neem treatments did not alter the concrete integrity and the physicochemical parameters. We reached a promoted long-term corrosion protection of 95% after 182 days of evaluation. Thus far, our current results open up a new promising “green” road to the conservation of carbon steel in reinforced concrete for the construction industry. The extensive industrial use of carbon steel in reinforced concrete structures may undergo a critical integrity degradation process generated by different corrosion mechanisms ,2,3,4. TThe application of green corrosion inhibitors has suggested being a straightforward and versatile procedure for protecting metallic structural materials without outcomes of significant pernicious effects. Interestingly, the management of green inhibitors has requested progressive manufacturing and application platforms, for example, vapor phase, polymer bases, ionic liquids, and plant extracts ,8,13. ThIt is important to highlight that the organic compounds extracted from plants have shown higher efficiency as corrosion inhibitors. Therefore, recent efforts have focused on development ,14. MoreThe neem leaf extract was prepared using 150 g of fresh leaves immersed in 750 mL of distilled water at room temperature, and the mixture was left in maceration for 24 h. To retain the solid materials, the extract was filtered using a 415 VWR filter. The final aqueous extract was stored at 4 °C in dark conditions for future tests.Commercially available corrosion inhibitors used in this work were Sika CNI, Eucon CIA, and DCI. All of these corrosion inhibitors were around 30% calcium nitrite by weight and have been formulated to meet ASTM C 494 Type C (Accelerating Admixtures) ,20,21,22In order to evaluate the integrity of the reinforced concrete after the incorporation of the neem leaf extract and the commercial corrosion inhibitors, concrete specimens were manufactured with materials from Mexicali, Baja California, México. Details of the materials and their characteristics are presented below.Holcim Apasco Class 40 Composite Portland Cement (CPC 40) was prepared following standard NMX-C-414 and its equivalent to ASTM C 150 at Type I ,24. The 3 (GS), respectively. On the other hand, the natural sand (AN) was used as fine aggregate with a retention degree below 4.75 mm, and a density of 2.60 kg/m3. The aggregates meet ASTM 33 and are divided into two categories: coarse aggregate and fine aggregate . Two typNon-potable water was used, which meets the chemical limits for concrete mixing water according to ASTM C1602 .A medium-range water-reducing admixture (Sikament 792), plasticizer, and curing retardant for concrete was considered to improve concrete workability properties, which meets ASTM C 494 as Type D (water-reducing and retarding admixtures) ,27.w/c) of 0.65, maximum aggregate size of 25 mm, slump 10 cm (±2.5 cm), gravel–sand ratio of 66%/34% and a GT-GS ratio of 70%/30%. The working conditions were the medium-range water-reducing additive Sikament 792 in a dosage of 5.5% by weight of the cement [Only one sample for each corrosion experiment was prepared. The concrete admixtures were designed in accordance with Portland Cement Association (PCA), using a water/cement ratio , cM, is the net mass of concrete, mM, mass of the container, mV, volume of the container. These measurements were carried out using a balance with a resolution of 0.01 kg.The unit weight calculation and the fresh concrete relative yield were generated according to ASTM C 138 . To calcyR is the relative yield, Y is the volume of concrete produced per mix (m3), and dY is the volume of concrete to produce (0.035 m3), M is the total mass of all materials in the mix (kg), and D represents the density of the concrete (kg/m3).On the other hand, for the calculation of the relative performance, the Equations (2) and (3) were used.In this test, we evaluated the air content of freshly mixed concrete by observing the change of concrete value due to a change in pressure. A portion of freshly mixed concrete was taken and placed in a container divided into three layers, each layer compacted with a rod and a rubber mallet and rooted from the base to the maximum height of the container. To calculate the air content, a lid system with a vertical air chamber and a calibrated percentage manometer with graduation for a range of at least 8% to 0.1% air was used in compliance with ASTM C 231 .In this study, two types of specimens (10 cm in diameter by 20 cm high) with and without reinforced-steel, were used, as shown in C is the maximum load reached and registered by the specimen in the test equipment (kg), and A is the specimen area (cm2).The compressive strength was evaluated in accordance with ASTM C 39 using Equation (4) . This evAfter the first 28 days required for curing the concrete specimens with and without carbon steel reinforced rods, the chloride penetration and corrosion inhibition effectiveness, in a 3.5% NaCl aqueous solution, was monitored for 182 days. During this time, the specimens were analyzed through 91 cycles of partial immersion and drying of 48 h to obtain short-term results.3 (silver nitrate) solution were applied to the freshly cut concrete surface, and the depth of chloride penetration was measured. This application caused the formation of two distinct regions: a region with a white precipitate AgCl (silver chloride) indicating the presence of chlorides and a brown zone indicating the absence of chlorides  electrode was used as a reference (MC Miller RE-5 brand), and the working electrode was the reinforced steel rod. Half-cell potential measurements were made using a Fluke 77 IV digital multimeter with a range from 1 to 6 V (resolution: 0.1 mV and precision: ± 0.3%) according to ASTM C 876. A copper/copper sulfate  and maintains the w/c ratio (0.65), resulting in out-of-tolerance. Moreover, the PCA indicates that an adjustment of 3 to 12 kg of water per cubic meter of concrete is required to increase the slump from 1.5 to 6 cm to be within the acceptance range of ASTM C 94 [w/c relationships.The slump results indicate that the mixtures with the different corrosion inhibitors and the neem leaf extract presented a consistency within the acceptance range according to ASTM C 94, for a slump of 10 cm ± 2.5 cm . On the STM C 94 ,47. Thes3 indicates that the concrete complies with the established parameter for structural concretes of average mass in a fresh state [The concrete mixtures unit weight between 2379 and 2383 kg/msh state . Moreovesh state ,33.The air content of concrete mixtures was between 0.9 and 1.4%, meeting the recommended air content in ACI 211.1 for airless concretes with an aggregate nominal maximum size of 25 mm .w/c ratio in airless concrete according to ACI 211.1 [w/c ratio below 0.65.The results at seven days are in a range from 27 to 29 MPa, where DCI presented the highest compression resistance. Furthermore, for 28 days, the samples with a resistance behavior from 32 to 35 MPa corresponded to the DCI mixture. These results showed that neem leaf extract and the commercial corrosion inhibitors could comply with structures exposed to freezing and thawing water, freezing and thawing in humid conditions, and chlorides, since they presented compressive strengths above 32 MPa. In addition, they meet a compressive strength for a lower CI 211.1 . This inw/c ratio since ACI 318 specifications require a minimum 0.40 w/c ratio for this condition [This behavior indicates that the rods in the steel specimens were in an area with free chlorides and soluble in water after 91 and 182 days of exposure. This short-term penetration in all the specimens was expected due to the 0.65 ondition ,49.On the other hand, the addition of neem leaf extract and corrosion inhibitors promotes chloride penetration, even presenting an air content lower than Blank in the fresh state concrete characteristic. The penetration of chlorides in the corrosion inhibitors may be due to the properties of the additives, such as Type C accelerating admixtures based on ASTM C 494. This characteristic could influence faster evaporation of water in the concrete and form more capillary channels in the concrete mass because these admixtures decrease the time to begin the transition of the mixture from the plastic to rigid state, accelerating the setting in the cement paste, conditioning it to absorb liquids and cause a faster flow capacity through it ,51. ThisIn general, the behaviors for all corrosion inhibitors show two stages, a decrease at 105 days where the chances of corrosion ranged from 50% (Sika CNI) to 95% , and an increase until the last day of analysis at 182 days, as presented in Nmai’s work . The res2+ ions and releasing electrons from the d-orbital of Fe, which can interact with the lone pair of O and the vacant π electrons of azadirachtine forming covalent coordination bonds. In these conditions and if the steric features of the azadirachtine molecule permit certain planarity, the molecule adsorption will prevent the corrosion of the metal [Previous studies have specified the interaction of secondary plant metabolites on the metal surface. Secondary metabolites such as alkaloids, flavonoids, tannins, and terpenoids protect against corrosion in different aggressive environments ,54. Langhe metal ,58,59,60he metal . The afoThis explanation may be interpreted as an increase in effectiveness of the neem leaf extract as, over time, the extract containing the secondary metabolites completely covered the surface of the reinforced steel protecting against corrosion ,62.Combining the results elucidated in this study, the following conclusions can be stated:In terms of concrete integrity, neem leaf extract meets fresh and hardened concrete characteristics, indicating that it does not alter their physicochemical parameters.For the penetration of chlorides, the neem leaf extract showed similar results to those of commercial inhibitors. The corrosion inhibiting effect of the neem leaf extract shows a favorable result for the reinforcing steel after 105 days of exposure. The probability of corrosion was 5% according to the Stratful criteria. This effectiveness was equal to or better than inorganic corrosion inhibitors currently found in the construction industry.Neem leaf extract shows a promising effect in inhibiting carbon steel corrosion in reinforced concrete, opening a possibility of incorporating this green inhibitor in the construction industry.According to the present results, new experiments including at least three specimens per test are recommended in order to statistically support the corrosion inhibition of neem leaf extracts’ efficiency on steel-reinforced concrete structures.


This paper deals with the possibility of using different types of waste glass powder in high-performance concrete (HPC) mixtures as a fine fraction replacement. Subsequently, both fractions are used in this research in concrete as a substitute for fine sand and silica flour. To use waste glass in a basic building material such as concrete, it is necessary to verify the basic chemical properties of the selected waste materials. Apart from the basic chemical properties, its environmental impact also appears to be an essential property of waste materials in general. Therefore, the research is mainly focused on the leaching and ecotoxicity experiments on high-performance concrete. HPC mixtures are designed based on the results of the analyzed chemical properties and previous research performed by our research team. Ecotoxicity of these concretes is then verified using Czech standards to evaluate. The results showed a positive impact on the ecotoxic properties of waste glass when used in concrete. A new ecotoxicity classification of waste materials and concrete mixes containing waste materials is proposed as a result of this research and summarized in the conclusion of this paper. This issue is related to the global increase in waste [In the last few years, one of the main problems has been the declining number of non-renewable resources and raw materials. However, these materials are closely linked to negative environmental impacts, including high primary energy consumption and COin waste . AccordiAbout 10.9 thousand tons of this waste is glass, and about 39.7 tons of waste glass is from municipal waste . HoweverWithin these intentions, it is appropriate to consider regular and high-quality concretes, which, with lower material consumption, may have the same (or better) properties than regular concrete. This study seeks to provide the possibility that the use of waste glass would bring. It is necessary to be aware of the risks associated with the use of waste materials and to verify, in particular, the impact on the environment and toxicity, given that efforts are being made to reduce the use of primary raw materials not only because their resources are depleted but also due to environmental threats.2 emissions, cement has the largest footprint and energy consumption. Therefore, the reduction in size of the cement industry is one of the global sustainability concerns of the 21st century [Focused on the ingredients of concrete, and especially its effect on the environment, the attention of researchers is preferentially directed towards cement. Its properties when used in concrete are indispensable; however, the energy expended in its processing, in relation to carbon dioxide that is produced, is significant. In terms of CO century . As a paSilica flour is formed after the crushing and subsequent grinding of quartz sand to the required roughness. Quality and especially volume uniformity is ensured by modern equipment in production. The properties of silica flour have been investigated in several studies, usually compared with cement and limestone powder as well ,8. It haMicrosilica  is known as a by-product of the smelting process of silicon metal and ferrosilicon manufacturing. After some research ,11,12, mWhile the use of microsilica in concrete was based on research ,13,14,15After summarizing all these factors, a convenient raw material for the partial replacement of cement, silica flour, or fine sand in concrete, another perfect pozzolan—glass—was chosen. This choice was based mainly on chemical characterization, which was partly solved in previous research . RegardiThe question is whether it is necessary to replace raw materials in concrete. Three types of waste glass powder are used as a full silica flour replacement in concrete. Although the chemical properties vary while using different types of waste glass powder, the properties verified for proper concrete utilization are tested, optimized, and verified ,17. BaseTo verify the suitability of the use of waste glass and concrete that contains waste glass, specific procedures were chosen according to the decrees of the Czech Republic. One of the main points of this work  is ecotoxicity. Ecotoxicology is a multidisciplinary field of modern attitude to deal with the verification of environmental and anthropogenic impacts on ecosystems  . The expThe ecological risk assessment is mostly expressed in EC50 (effective concentration causing 50% effect in comparison with control). The other possibilities are LC50  or LOEC (lowest observed effect concentration) . The valThe novelty of this study is in the performed ecotoxicology tests, with the focus on building materials such as concrete. It is common that concrete is tested to verify mechanical or physical properties . However, equally important are the environmental issues and the caused impacts.The aim of our research was to investigate whether a hazardous glass waste leaching and ecotoxic potential could significantly decrease after incorporation into concrete mix.The work procedure is graphically explained below in Three samples of waste glass powders from different sources were chosen. Grinding glass, municipal waste glass, and photovoltaic glass in the form of powder were measured and analyzed to evaluate their impact on the environment. Silica flour (used as the reference sample) was exposed to the same experiments for comparison. AAS was made to collect the basic properties and evaluate the potential risks.SF) and three concrete mixtures containing waste glass  and ecotoxicity experiments were made to verify the prediction of eliminating the ecotoxicity of waste glass when used in concrete.Given the results, the design of concrete mixtures was made. One reference mix as the sample . Subsequently, both fractions are used in this research in concrete as a substitute for fine sand and silica flour. The main aims are to save the number of primary resources and eliminate carbon dioxide production [The last type of glass we explore in this research is glass from photovoltaic panels. Photovoltaic panels are a modern source of energy in the Czech Republic, and their use on a massive scale began approximately 15–20 years ago, which subsequently contributed to the reduction in panel prices in 2009–2010 ,29. As toduction .Based on the results of the chemical properties, the concrete mixes were designed. With regard to the results, one reference concrete mix and three concrete mixes containing different types of waste glass were tested.The reference concrete mixture was made according to the recipe verified by the Department of Architectural Engineering at the Faculty at Civil Engineering, CTU Prague.100 and MWG100).The mixture containing waste glass from grinding jewelry  and crushing municipal waste glass (MWG) was added, as a full replacement for silica flour, to the concrete mixture. The replacement, in both cases, was realized in full weight ratio. The replacement ratio is 100% in both mixes .Full replacement of silica flour was provided by waste glass powder from photovoltaic panels. In addition, 50% of the natural sand (fraction 01/06) was replaced by photovoltaic glass with the requisite fraction (fine sand 01/06). The replacement ratio was 100% with silica flour and 50% with sand  for 24 h [g, 10 min, 25 °C) and filtered through a membrane paper with pores of 5 μm. For the concrete samples, the leachate procedure was adjusted: concrete cubes (aged 28 days) were placed in 3.6 L bottles and covered with H2O in the ratio 100 g/1000 mL. The bottles were covered, and the samples were left, without shaking, at room temperature. After 24 h, the concrete cubes were removed, and the leachates were filtrated without centrifugation step. pH and electrical conductivity were determined in the filtrated leachates at room temperature. All leachates were prepared in two replicates. Selected elements  were determined using atomic absorption spectrometry with flame atomizer 280FS AA, developed by Agilent Technologies, Inc. , in leachates after acidification by HCl to a pH of 2.0.For silica flour and glass, air-dried samples of 100 g were mixed with 1000 mL of Hfor 24 h . Consequ−1). pH adjustment was not included in the leachate’s treatment.Ecotoxicological bioassays were performed with original untreated leachates, leachates diluted with nutrient media in a concentration range between 330–800 mL/L, and leachates diluted 10 times and amended with relevant inorganic nutrients according to the control media of the given test species , Belgium). The experiment was designed following ISO guideline 6341 [An acute toxicity assay was performed with ine 6341 , with soine 6341  was usedFive juvenile individuals were transferred into 25 mL beakers with 20 mL of leachate or control sample, covered with transparent film, and put under stable temperature (20 ± 1 °C) and light cycle . Each sample was represented by four replicates, whereas the control was represented by six replicates. The inhibition of daphnia mobility (viability) was observed after the 48 h exposition.Desmodesmus subspicatus, strain Brinkmann 1953/SAG 86.81, which was obtained from CCALA IBOT, AS CR  partly following the ISO guideline 8692 [Algae growth inhibition test was performed with the freshwater green algae ine 8692 . Bold Baine 8692  was usedLemna minor, strain Steinberg originated from Federal Environmental Agency . Steinberg medium modified by Altenburg (pH 5.5 ± 0.2) [A duckweed assay was proposed by ISO guideline 20079 [The total frond area was determined by image analysis using NIS Elements . Growth rate (GR) was calculated from the values based on repeated measurements during the test exposure, i.e., 0th, 3rd, and 7th day. After the 7-day exposition, fronds were extracted by pure methanol  and the total chlorophyll content was determined spectrophotometrically (Shimadzu UV-1900) according to .tX0 is the value of the parameter in t0 (d), and Xt1 is the value of the parameter in t1 (d). [In algae and duckweed, the growth rate (GR), based on cell number and frond area, respectively, was calculated using Equation (1): t1 (d). .I is the inhibition/stimulation of growth (%), cX0 is the average value of control, and ciX is the average value of sample i. [All ecotoxicological data  were consequently expressed as the values of inhibition/stimulation in percentage, where tested organisms in leachate were compared to control organisms using the following equation:ample i. .EC50 values were calculated from the inhibition data for all ecotoxicity tests using non-linear regression. A one-way ANOVA and Dunnett’s post-hoc test was performed to compare samples with controls at the α level of 0.05. Based on the Dunnett test, the highest sample concentration, which was statistically not different from the control sample and had no stimulation effect at the same time, was chosen as the NOEC value. The statistical analyses were performed using GraphPad Prism software . The level of ecotoxicity was finally classified according to −1) and Zn (0.11 mg·L−1) was found in MWG leachate. These metals can be problematic in natural freshwaters. However, Desmodesmus subspicatus (previously named Scenedesmus subspicatus) was found tolerant to similar contents of these metals [The ecotoxicity testing of wastes is required by the Czech legislation. Provided that the material is miscible with water, chemical analysis and aquatic toxicity of the leachate are performed . Accordie metals . Therefo100 and MWG100) and around 36.5% of photovoltaic glass and photovoltaic sand (PG100/50). Elements which are common components of Portland cement, i.e., Ca and K, were leached more intensively from the concrete mixes, with one exception (GG100).In leachates prepared from concrete mixes, the majority of 13 risk metals were also below the detection limit, Ca increased while Na and Si decreased, Al decreased below the detection limit, and Mg and Fe decreased or stayed at a similar level when compared to leachates from glass materials. Higher leaching of the selected elements  in glass powder, compared to concrete cubes, was expected due to the higher surface area of the powders. Moreover, concrete mixes are formed of only approximately 10% of glass powders  in this leachate. The concrete mix with photovoltaic glass had different features from the other concrete mixes, as expected. Due to a high porosity of PG100/50 , which cause ≥50% inhibition effect in any test species, are considered ecotoxic, i.e., the original solid waste is classified as hazardous. This category, i.e., hazardous waste, was retained in the proposed scale for waste characterization, mainly for the needs of applied research in the use of wastes as secondary raw materials in the construction sector.When dilution of the leachate decreased the lethality/high inhibition thoroughly, a sample was considered non-toxic. For this purpose, the original toxicity scale was proposed, as presented in −1) [−1), which was approximately 1000 times higher than that of the Steinberg medium, and lack of magnesium (0.47 mg·L−1 in GG vs. 9.87 mg·L−1 in Steinberg) at the same time. In addition, GG also contained increased levels of aluminium (7.84 mg·L−1). Finally, the PG sample was classified as hazardous waste because it was found to be lethal to daphnia at every concentration tested, including the 100 + n sample treatment. The lethality of PG leachate was caused, most likely, by the high content of Al (27.9 mg·L−1). Aluminum poses a high environmental risk for the water flea (Daphnia magna) and other species of crustaceans. [−1 represented EC50 in the daphnia acute test. Our results were close to this finding, since the nominal concentration of Al in PG (100 + n) mg·L−1 was 2.79 mg·L−1. The lethality (100% immobilization) of this PG dilution was possibly caused by the presence of other chemicals and the overall different chemical composition of the leachate, in comparison to pure aluminium chemical (AlCl3) dissolved in the control medium [The reference material, silica flour (SF), was found to be non-toxic since only the lack of nutrients in the original leachate inhibited the growth of organisms. This result was expected, because this material is considered inert . Glass i−1) ; neverthtaceans.  found thl medium . One intAluminium is known to be toxic under highly acidic and highly alkaline conditions, while, under neutral pH, it tends to form insoluble complexes, which are not bioavailable for organisms . The low−1). PG100/50 leachate had the lowest EC50 value in daphnia and duckweed, which indicated the highest inhibition effect among the concrete mixes  toxicity tests will be also performed.In general, it can be said that the view to building structures in terms of ecotoxicology is an innovation that is not common in the Czech Republic. A new ecotoxicity classification is suggested, which is designed for building materials. Consideration of ecological impacts should be one of the first tendencies in determining the suitability of the use of concrete in the natural environment. The effort to solve this question, such as testing or developing a new methodology, is becoming essential not only in the Czech Republic. This specific point of view is considered a very new approach.


Antibiotic use is associated with several antibiotic-related harms in vulnerable, older long-term care (LTC) residents. Suboptimal antibiotic use may also be associated with harms but has not yet been investigated. The aim of this work was to compare rates of poor clinical outcomes among LTC residents with UTI receiving suboptimal versus optimal antibiotic treatment.Clostridioides difficile infection (CDI), or death within 30 days of antibiotic discontinuation. Shared frailty Cox proportional hazard regression models were used to compare the time-to-event between suboptimal and optimal treatment.We conducted a retrospective cohort study among residents with an incident urinary tract infection (UTI) treated in Veterans Affairs LTC units (2013–2018). Potentially suboptimal antibiotic treatment was defined as use of a suboptimal initial antibiotic drug choice, dose frequency, and/or excessive treatment duration. The primary outcome was time to a composite measure of poor clinical outcome, defined as UTI recurrence, acute care hospitalization/emergency department visit, adverse drug event, Among 19,701 LTC residents with an incident UTI, 64.6% received potentially suboptimal antibiotic treatment and 35.4% experienced a poor clinical outcome. In adjusted analyses, potentially suboptimal antibiotic treatment was associated with a small increased hazard of poor clinical outcome  as compared with optimal treatment, driven by an increased hazard of CDI .In this national cohort study, suboptimal antibiotic treatment was associated with a 6% increased risk of the composite measure of poor clinical outcomes, in particular, a 94% increased risk of CDI. Beyond the decision to use antibiotics, clinicians should also consider the potential harms of suboptimal treatment choices with regards to drug type, dose frequency, and duration used.The online version contains supplementary material available at 10.1186/s12877-021-02378-5. Clostridioides difficile, antibiotic allergies, and other adverse drug effects and drug toxicities [Antibiotic resistance poses one of the most urgent and widespread threats to public health and is driven by antibiotic use , 2. Antixicities –14.The most common driver of antibiotic use and reason for inappropriate antibiotic use in LTCFs is urinary tract infection (UTI) . A studyPrior studies have assessed the harms associated with unnecessary antibiotic use , 21, 22.The study design and methods were defined a priori in the study protocol, which was approved by the Institutional Review Board (IRB) and the Research and Development (R&D) Committee of the Providence Veterans Affairs Medical Center prior to initiation with a waiver of the informed consent process. All methods were carried out in accordance with relevant guidelines and regulations.We used data from the national VA Corporate Data Warehouse including microbiology reports, inpatient and outpatient care, diagnoses, procedures, surgeries, demographics, vital status, inpatient and outpatient medications, laboratory, and vital measurements. We conducted a retrospective cohort study of residents with a suspected incident UTI (first during the study with none in the year prior) treated in VA long-term care units (known as community living centers or CLCs) from January 2013 to December 2018. We included residents with incident CLC UTIs, however they could have had a UTI in another setting  previously. Figure We compared residents with UTIs receiving potentially suboptimal antibiotic treatment with those receiving potentially optimal antibiotic treatment. Potentially suboptimal antibiotic treatment was defined as use of a suboptimal initial antibiotic drug choice, dose frequency, and/or excessive treatment duration . InitialClostridioides difficile infection (CDI), or death. For residents who experienced more than one of these poor clinical outcomes of interest we considered the event that occurred first. For secondary outcomes, we assessed time to each poor clinical outcome separately. We censored residents who were alive and without the event of interest after 30 days. Table The primary outcome of interest was time to a composite measure of any of the following poor clinical outcomes within 30 days of antibiotic discontinuation: UTI recurrence, acute care hospitalization or emergency department (ED) visit, adverse drug event, t test or the Wilcoxon rank sum test for continuous data, as appropriate. To account for the multi-level structure of our data , CLC was included a random effect in our models with log-normal distribution to represent shared frailty among residents of the same CLC [We compared the composite measure of poor clinical outcomes, as well as the individual clinical outcomes, among residents with incident UTIs receiving potentially suboptimal and optimal antibiotic treatment. Differences between groups were analyzed using chi-square for categorical data and Student’s same CLC . Cox modsame CLC . The adjsame CLC . We alsosame CLC . All presame CLC .We conducted subgroup analyses among residents who were initially treated with only one antibiotic class . We also conducted subgroup analyses among residents who received only one subtype of suboptimal treatment . Finally, we conducted sensitivity analyses with varying follow-up times . We used a shorter 14-day follow-up time as some events such as UTI recurrence, acute care hospitalization or emergency department visits, and adverse drug events, tend to occur during or shortly after exposure to antibiotics , 36. Othn = 12,718) received potentially suboptimal antibiotic treatment and 35.4% (n = 6983) received potentially optimal antibiotic treatment. The CLC at the median used potentially suboptimal antibiotic treatment in 66.3% of residents with an incident UTI .From 2013 to 2018, we identified 19,701 CLC residents with an incident UTI treated in 120 VA CLCs treated for at least 3 days. Overall, 64.6% of residents (p < 0.001) and exposure to any antibiotic in the last 30 days (44.4% vs. 42.0%), and less likely to have a UTI diagnosis in the year prior (34.3% vs. 40.3%), compared with those receiving optimal antibiotic treatment.As expected, there were several differences in the baseline characteristics and initial (empiric) antibiotic treatment of residents receiving potentially suboptimal versus optimal antibiotic treatment Table . Those rn = 7337) of residents with an incident UTI experienced a poor clinical outcome within 30 days of antibiotic discontinuation  as compared with optimal antibiotic treatment. Receipt of potentially suboptimal antibiotic treatment was associated with an increased hazard of CDI , but not with any other individual clinical outcome assessed.Overall, 37.2%  as compared with optimal treatment can be found in Table ).In sensitivity analyses, potentially suboptimal antibiotic treatment was associated with an increased hazard of the composite poor clinical outcome using a shorter follow-up of 14 days, but was not with a longer follow-up of 60, 90, or 180-days  [Our work advances previous work indicating antibiotic use is associated with a number of unintended harms in LTCF residents , 38, 39.= 0.003) , 40, 41.= 0.003) –44. Anti= 0.003) . In our Our work also corresponds with existing research on unnecessary antibiotic treatment and associated harms, including CDI, acquisition of drug-resistant pathogens, and other adverse events , 45, 46.Our results were largely driven by an increased risk of CDI associated with suboptimal antibiotic treatment among residents with UTI. The risk of CDI was 1.94 times higher among residents who received potentially suboptimal antibiotic treatment as compared to those who received optimal antibiotic treatment. It is well-known that antibiotic use is one of the most important risk factors for CDI, and that any antibiotic exposure can lead to disruption of the normal gastrointestinal microbiota and result in CDI. Prior work among nursing home residents, demonstrated that a 7-day antibiotic course, compared with no antibiotic treatment, was associated with a 1.8 times increased risk of CDI . This prTreatment duration was longer among those who received suboptimal antibiotic treatment. A recent longitudinal case-cohort study among residents of nursing homes in Ontario, Canada found that antibiotic choice and duration had a significant impact on risk for CDI . CompareThe only subtype of potentially suboptimal antibiotic treatment that was associated with the composite poor clinical outcome and CDI in our study was potentially suboptimal dose frequency. The risk of CDI was 2.42 times higher among those treated with a suboptimal dose frequency versus optimal treatment. Potentially suboptimal dose frequency was also associated with hospitalization/ED visits and all-cause mortality. In prior work, a dose-dependent increased risk of CDI has been observed, with increasing cumulative defined daily dose of antibiotics resulting in increasing risks of CDI . Our resWe found no difference in risk for UTI recurrence for residents treated with potentially suboptimal or optimal antibiotic treatment. Previous work has found that among women with UTI, longer courses of antibiotics may be associated with increased risk of recurrent UTI, possibly due to alterations in urogenital flora –59. HoweIt is possible that suboptimal initial treatment could lead to clinical failure, the consequences of which could be serious and may include bacteremia, urosepsis, acute care hospitalization, and potentially death , 61. In We acknowledge the limitations of this retrospective cohort study. First, our study was not designed to assess causality, and there are important differences (known and unknown) between residents who received suboptimal and optimal antibiotic treatment. While we did adjust for confounders of suboptimal treatment and clinical outcomes, our findings neither confirm nor deny a causal relationship, as our findings may be confounded by unmeasured factors which affect suboptimal treatment and clinical outcomes. As such, while we found an association between suboptimal antibiotic treatment and poor clinical outcomes even after adjusting for several resident and CLC characteristics, this association may be impacted by residual confounding. Second, we defined UTI based on a urine culture and antibiotic treatment, per recommendations of the Infectious Diseases Society of America . While wIn this large national study of 19,701 CLC residents with an incident UTI, suboptimal antibiotic treatment was associated with increased risk of poor clinical outcomes. Our results were driven by a 94% increased risk of CDI with suboptimal use, meaning not unnecessary use, but not the use of the best drug, dose frequency, and duration. Our work expands on previous work which has found that antibiotic use and unnecessary antibiotic use are associated with a number of harms in vulnerable older long-term care residents. Beyond the decision to use antibiotics, clinicians should consider the potential harms of their antibiotic choices with regards to drug, dose, and duration, to ensure that residents are receiving the most optimal antibiotic treatment. Future research should continue to investigate the impact of suboptimal treatment UTI and other common types of infection among older vulnerable long-term care residents.Additional file 1: Table S1. Sensitivity analyses with varying follow-up times. Table S2. Sensitivity analyses using an alternate definition of poor clinical outcome which excludes CDI. Table S3. Study definitions used to measure potentially suboptimal antibiotic treatment, and subtypes of potentially suboptimal antibiotic treatment. Table S4. Diagnosis and procedure codes used for outcomes definitions.