Tetanus occurring during pregnancy is still an important cause of maternal and neonatal mortality in developing countries. This study estimated the trend of tetanus toxoid (TT) immunization coverage from 2006 to 2019 in Bangladesh, considering socio-demographic, socio-economic, and geospatial characteristics.The dataset used in this study was extracted from Multiple Indicator Cluster Surveys  including 28,734 women aged between 15–49 years. Data analysis was performed using cross-tabulation and logistic regression methods. Further, the spatial distribution of TT immunization coverage was also depicted.The trend of TT immunization (81.8% in 2006 to 49.3% in 2019) and that of taking adequate doses of TT (67.1% in 2006 to 49.9% in 2019) has gradually decreased throughout the study period. Among the administrative districts, North and South-West regions had lower coverage, and South and West regions had relatively higher coverage of both TT immunization and that of adequate doses. Antenatal TT immunization  was significantly associated with lower age , higher education , living in urban areas , having immunization card , using government facilities for birth , and receiving antenatal care (ANC) . In addition, living in urban areas , having immunization cards , and choosing others’ homes for birth  were significantly associated with adequate TT immunization. However, higher education , having poor wealth index , and receiving ANC  had lower likelihood of taking adequate TT immunization.The gradual decline in the TT immunization rate in the present study suggests the presence of variable rates and unequal access to TT immunization, demanding more effective public health programs focusing on high-risk groups to ensure adequate TT immunization. Clostridium tetani. Though people of all ages can get tetanus, pregnant women are more susceptible to this fatal disease, especially those not being adequately immunized (at least two doses) with tetanus-toxoid-containing doses [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5496662/[Tetanus is a deadly contagious infection caused by spore-forming bacteria ng doses . “MaternC5496662/–5. The tTetanus is highly responsible for neonatal deaths every year. Based on statistics from 2002, it is estimated that about 180,000 neonates died, which represents 5% of all neonatal deaths, among 218,000 cases in India due to inadequate TT immunization . BesidesNotably, there are 59 high-risk countries for the prevalence of maternal and neonatal tetanus . But mucDespite progress, it is still a burning issue for developing countries greatly in Asia and Africa , 21. StuNotably, after India, China, and Pakistan; Bangladesh was identified as the fourth-highest country for neonatal tetanus with estimated cases of 41000 annually . VulneraThis cross-sectional study used survey data sets from 2006, 2012–13, and 2019 of the Bangladesh Multiple indicator cluster surveys (MICS), an international survey initiative carried out by the Bangladesh Bureau of Statistics in collaboration with UNICEF. The MICS were developed and supported by UNICEF “focusing mainly on issues that directly affect the lives of children and women” allowing countries to generate evidence and recommended strategies to monitor the progress toward millennium development goals . The surThe two outcome variables used for this study were similar to previous studies , 18, 19.We considered explanatory variables according to their know association with the uptake of TT immunization , 32–34. IBM SPSS statistics 26.0 version was used for the analysis. First, simple descriptive tests were done to observe the exact group frequencies, percentages, minimum, maximum, range, etc. Then, Pearson Chi-square tests were carried out to imprint the association of covariates with the two dependent variables. Multicollinearity between independent variables was measured using correlation coefficient and the value of all the variables was less than 0.5 indicating the absence of multicollinearity. After that, logistic regression models for the binary outcome were used to analyze the multivariable association between covariates and outcomes. Tableau Desktop version 2021.2 was used to create the line chart and ArcGIS v10.5 to visualize the % changes occurring across 64 districts of Bangladesh. All tests were two-sided and had statistically eligible significant values below 0.05 with 95% confidence intervals. Forest plots were used for the graphical representation of the significant findings.http://mics.unicef.org/surveys.This study analyzed survey data from UNICEF, where all the personally identifiable information of participants had been removed. The national statistical office, Bangladesh Bureau of Statistics, and UNICEF obtained informed consent from survey participants before their participation. Because we used publicly available de-identified data, our work was exempt from full ethical review process and approved by the Research and Ethical Committee of Department of the Biochemistry and Food Analysis, Patuakhali Science and Technology University . In addition, upon completing the registration process, the authors were granted permission to download and use the datasets. The data are available online: After excluding the missing values, 28,734 pregnant women aged 15–49 years were included in our study . As showThe education of the participant is a significant covariate of adequate TT immunization. This data demonstrates that in 2006 and 2012–13, the women who did not complete their secondary education had significantly lower  and  uptake of adequate TT doses than uneducated women  Tables. This study investigated the factors associated with TT immunization coverage among pregnant women aged 15–49 years. We observed that for MICS (2006), MICS (2012–13) and MICS (2019) the prevalence of TT immunization was 81.8%, 61.3%, and 49.3%, respectively. Moreover, the prevalence of adequate TT doses was 67.1%, 65.1%, and 49.9% for MICS (2006), MICS (2012–13), and MICS (2019), respectively. Overall, the prevalence shows a decreasing trend across the survey years in Bangladesh. The prevalence of adequate TT doses was 49.9% from the latest survey (MICS 2019), which is low as compared to the study  showed tThe high socio-demographic condition is associated with TT immunization. The higher TT immunization rate among younger women in the present study might be attributed to the improved formal female education and access to modern media outlets. By previous studies, age is an insignificant factor regarding adequate doses of TT immunization . In contBangladesh has achieved remarkable health improvements during the last two decades . More reThis study showed that women who uptake TT immunizations or adequate TT doses using immunization cards had a higher chance of being protected from tetanus. This finding is similar to studies conducted in Ethiopia and Ghana , 43, whiAnother important factor significantly associated with TT immunization was ANC follow-up, consistent with previous studies conducted in different countries worldwide , 18. ThiThe spatial analysis discovered some district-wise variations in the change rate of TT immunization from 2006 to 2019, with Rangamati and Bandarban districts experiencing the worst. Moreover, regarding adequate TT doses, the situation was worse in Bandarban, Cox’s Bazar, Pabna, Natore, Thakurgaon, and Nilphamari districts. Therefore, the policy focus here would be on the peripheral districts and the hill tracts in Bangladesh to improve women’s health literacy in remote areas and ensure maternal healthcare access.This study has several strengths. First, this is the first study to demonstrate trends of TT immunization among women during the last pregnancy in Bangladesh. Second, we used data from three nationally representative datasets and the findings can be generalized to a whole nation. However, this study does have some limitations. Due to the cross-sectional nature of the study, causal inference of the association between TT immunization and women’s health cannot be drawn. Since this study asks participants about past exposure and numerous vaccines indicated in the period in question, recall bias may occur. Social media exposure variables like watching television, using a computer, and listening to radiofrequency were not common in the three datasets and are missing from the analysis. Secondary data used in the analysis allowed us to lack control over the variables of interest to include in the analysis.Our study concludes that the trends of receiving TT immunization and adequate doses have decreased over the years in Bangladesh. In addition, the findings suggest that the socio-demographic, socio-economic, and maternal health-related factors are accountable for TT immunization. The official ANC visit, early ANC visit, and exemption of user fees should be considered. Interventions to reduce the observed inequalities between districts, especially the peripheral region, need to be emphasized. Likewise, public health interventions targeting rural women who are uneducated, living in lower wealth quintiles, and women who do not attend ANC facilities can be encouraged for TT immunization. The governments and other stakeholders should raise awareness in promoting female education to correct women’s perceptions of the importance of vaccination across different regions of the country.S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.S4 Table(DOCX)Click here for additional data file.


In the last decades, the science and technology of all-ceramic teeth restorations witnessed the fastest-growing field of restorative materials in research and development for fixed prosthodontics. Due to their properties, characterized by a high level of biocompatibility, excellent optical properties, and high fracture resistance, all-ceramic material can also be used in the posterior areas of the dental arches. However, metal-ceramic fixed partial dentures are still perceived as the golden standard for those restorations, thanks to the positive clinical outcomes. Irrespective of the materials of which fixed partial dentures are performed, their success rates depend on the expected outcome and on how they perform in the oral environment. Such conditions of failure restorations may include biological factors  or technical factors . Our aim is to provide the current evidence for the efficacy of metal-ceramics and all-ceramics in the treatment of multiple posterior edentulous spaces. Moreover, we aim to compare the survival rates of metal-ceramic and all-ceramic fixed partial dentures in terms of functionality and biocompatibility in all the aforementioned clinical situations. Our results have shown that all all-ceramic systems, especially densely sintered zirconia and reinforced glass ceramics, have a promising future to satisfy both practitioners and patients. However, technical and biological complications need to be taken into account when planning multi-unit fixed partial dentures for the posterior areas.The metal-ceramic fixed partial prosthesis is the golden standard for posterior tooth restorations. Following the demands of patients and clinicians for metal-free restorations, all-ceramic materials were developed as they offer an adequate alternative with better optical qualities and good mechanical properties. This study aims to carry out a bibliographic review to assess the survival rate and the biological and technical complications of all-ceramic and metal-ceramic fixed partial dentures. An electronic search for articles in the English language literature was performed using PubMed (MEDLINE). This literature review focused on research studies between 2010 and 2020 that performed clinical studies on tooth-supported fixed partial dentures with a mean follow-up of at least 3 years. All the studies, which analyzed the survival and complications of tooth-supported fixed partial dentures, were included. Thus, 14 studies reporting on 756 all-ceramic and 160 metal-ceramic fixed partial dentures met the inclusion criteria. A comparative analysis was carried out based on all the data existing in the studies included in this review. The metal-ceramic fixed partial dentures showed survival rates of 95% to 100% at 3-, 5-, and 10-year follow-up periods. Zirconia fixed partial dentures were reported to have survival rates of 81% to 100% at 3-, 5-, 9-, 10-year follow-up evaluations. The reinforced glass-ceramic fixed partial dentures showed survival rates of 70% to 93.35% at 5 years, while the alumina FPDs showed a survival rate of 68% at 3 years follow-up. The incidence of caries and loss of vitality were reported as higher for all-ceramic prostheses as compared to the metal-ceramic ones. A significant framework fracture was reported for glass-infiltrated alumina fixed partial dentures in comparison to metal-ceramic fixed partial dentures. All-ceramic and metal-ceramic restorations showed similar survival rates after 3 years, although all-ceramic restorations have problems with technical complications such as chipping, which can lead to framework fractures over time. The treatment of edentulism with fixed partial dentures (FPDs) by replacing missing teeth is well established and provides promising clinical outcomes. The metal-ceramic FPDs are still perceived as the golden standard for posterior tooth restorations. They provide excellent mechanical properties but lack aesthetic characteristics due to the dark framework underneath, which has to be veneered and can be challenging in areas with insufficient space ,3,4,5,6.All-ceramic materials seem to offer an adequate alternative with better optical qualities, which are more tooth-resembling in terms of color and increased translucency ,7,8,9,102), which is an inorganic metallic oxide material, can be found in three temperature-dependent phases, namely: monolithic (up to 1170 °C), tetragonal (1170–2370 °C) or cubic (2370 °C up to the melting point) [2 is unsuitable to be mechanically or structurally applied at room temperatures, adding yttrium-oxide (Y2O3) results in the stabilization of the dense tetragonal phase and, thus, presents yttria-stabilized zirconia (Y-TZP). The outcomes of the use of Y-TZP are promising due to its high flexure strength and fracture toughness in comparison with other ceramic core materials [In order to satisfy the increased demand of patients and practitioners for high function, aesthetics, and biocompatibility regarding restorations, a broad spectrum of ceramics was introduced into medical practice . Due to g point) ,25. Becaaterials ,27. Thisnal 1170–70 °C or Irrespective of the materials from which they are made, the success rates of FPDs depend on the expected outcome and on how they perform within the stomatognathic system. Failure of restoration is defined as any circumstance leading to replacement ,28,29,30To conclude, considering the above circumstances, the aim of our study is to provide a literature review of the current evidence for the efficacy of metal-ceramics and all-ceramics in the treatment of edentulous spaces in the posterior areas of the dental arches. Moreover, we aim to compare the survival rates of metal-ceramic and all-ceramic bridges in terms of functionality and biocompatibility in all the aforementioned clinical situations.An electronic search for articles in English language literature was performed using Pub Med (MEDLINE). This literature review focused on research articles between 2010 and 2020, while the following searches and search terms were applied: all-ceramic FPDs, zirconia, lithium disilicate, metal-ceramic FPDs, porcelain fused to metal, metal-ceramic restoration, all-ceramic restoration, all-ceramic and metal-ceramic, FPD esthetic, FPD biologic, FPD function .The inclusion criteria for the study selection were: randomized controlled trials; prospective longitudinal studies and retrospective longitudinal studies reported posteriorly; FPDs containing details on the characteristics of FPDs, with a minimum follow-up period of 3 years. All full-text articles with studies of the type mentioned above and in which the survival and complications of metal-ceramic and all-ceramic tooth-supported FPDs were analyzed were also included in the current review. The exclusion criteria: papers about studies in vitro or animal studies related to implant-supported FPDs, only single-tooth restorations, and frontal restorations, as well as studies with less than 3 years follow-up.The electronic search process was systematically conducted within two reviews in three stages. In the first stage, 9720 titles were identified based on the keywords. These titles were screened for meeting the inclusion criteria. Following this process, 9342 titles were excluded. In the second stage, the abstracts of the remaining titles were analyzed, and, consequently, 335 studies were excluded because they were considered inappropriate upon the review of the title and abstract or because they were duplications. In the third stage, the full-text articles were analyzed based on the inclusion/exclusion criteria. Thus, the material and methods, results, and discussions sections of these studies were thoroughly analyzed. The 29 out of 43 full-text articles were excluded, which brought the final number of this review to 14 articles, with the view of analyzing the survival and complications of metal-ceramic and all-ceramic tooth-supported posterior FPDs .Further, a comparative analysis has been developed based on all data existing in the studies included in this review. The data was entered in spreadsheet software ; the results were expressed numerically and as a percentage using this software. The following descriptive parameters were extracted: author(s), publication year, framework material, study design, observation period, number and mean age of patients. Number of FPDs, mean follow-up time, number of failures, estimated annual failure rate and estimated survival after N years, biological complications including secondary caries, periodontal disease, loss of vitality, abutment fracture, technical complications including framework or core fracture, chipping, ceramic fracture and loss of retention were also recorded for each of the 14 eligible studies.The FPDs were evaluated as survived if they were present with/without complications during the whole observation period. Additionally, they were evaluated as successful if the FPD did not present any biological or technical complications at the time of the follow-up. Failure rates were calculated by dividing the number of events (failures) in the numerator by the total FDP exposure. The numerator could usually be extracted directly from the publication. The total exposure time was calculated by taking the sum of: exposure time of FDPs that could be followed for the whole observation time. For each study, event rates for the FDPs were calculated by dividing the total number of events by the total FDP exposure time in years.Overall, 14 studies published between 2010 and 2020 met the inclusion criteria of the present literature review, respectively ; 3 studiThe majority of the studies (6) were prospective 42.9%) [.9% 42,44,48,50, The majority of the studies for all-ceramic FPDs had a prospective and retrospective design, and one was a randomized clinical control trial (RCT). The five randomized clinical control trials ,45,46,47Most of the studies evaluated densely sintered zirconia (49%), followed by metal-ceramic (25%), reinforced glass-ceramic (21%), and glass-infiltrated alumina (5%) .The systems that were used and evaluated in the included studies were: Procera , Cercon , Lava (Pre-Sintered) , DC-Zircon (HIP) , CAM sysFor metal-ceramic FPDs, 5 out of 14 studies provided data on 160 FPDs after a mean follow-up period of 5.2 years. The number of total failures was 2. The mean survival rate after 3, 5, and 10 years ranged from 95% to 100%, with an estimated annual failure rate of 0.72–1.84%. Four studies reported survival rates of 100% even after an observation period of 10 years. The mean-survival rate was 98.28%, with an estimated annual mean failure rate of 0.46% .For all-ceramic FPDs, the results were divided into reinforced glass-ceramic (lithium disilicate), glass-infiltrated alumina (InCeram), and densely sintered zirconia (Y-TZP). For the reinforced glass ceramics, 4 studies offered data on 211 FPDs; 24 restorations had to be replaced due to failure. Some of these FPDs also got lost after a mean follow-up period of 7 years. The survival rate after five years ranged from 70% to 95.35%, with a mean survival rate of 86.66%. The annual failure rates ranged from 0.93% to 7.14%, and the median value of the annual failure rate was estimated to be 3.0 .One study  providedFor densely sintered zirconia (Y-TZP), 10 studies contributed with 511 FPDs, from which 33 were reported as failures after an average follow-up period of 6.3 years. The survival rates ranged from 85% to 100% after observation periods from 3 to 10 years. The estimated annual failure rate had values ranging between 0% and 4.66%, with a mean value of 1.31%. The mean survival rate was 92.17% .The mean survival rates after 5 years were 100% for metal-ceramic FPDs, confirming the survival rates from the literature ,49 and sThe annual failure rates varied from 0% to 10.6% and the survival rates from 68% to 100% for the types of FPDs . Metal-cFrom a total number of 916 FPDs, secondary caries occurred on 26 abutments . DenselyFrom the evaluated studies, 6 of them reported cases of abutments losing their vitality throughout the treatment after cementation. Loss of abutment vitality occurred in 19 FPDs, with the majority (15 abutments) being all-ceramic FPDs, namely: densely sintered zirconia .Abutments of FPDs that were lost due to periodontal disease were reported in 9 FPDs. The prevalence was 6 all-ceramic FPDs and 3 metal-ceramic FPDs. Of the all-ceramic FPDs that were reported as failures, five were made from densely sintered zirconia and one FPD from reinforced glass-ceramic .The occurrence of failure due to abutment tooth fracture was reported in 9 abutments that were lost during the observational period. All of the reported failures were all-ceramic FPDs, whereas seven abutment teeth fractures were made of densely sintered zirconia and two were made of reinforced glass-ceramic .The occurrence of framework or core fracture was reported in 8 out of the 14 studies evaluated in this systematic review. The number of reported failures due to framework fracture was 64 out of 916 fixed partial dentures (6.98%). The affected FPDs were all made from all-ceramic materials, including 16 FPDs made from densely sintered zirconia, 11 restorations made from reinforced glass-ceramic, and 11 made from alumina .Even though most of the lost FPDs were made from densely sintered zirconia, alumina frameworks were reported with a higher prevalence in framework fractures , consideThe occurrence of chipping was reported in the majority of the studies included in this literature review; 194 FPDs showed chipping as a complication with different degrees of severity. The majority of chipped FPDs were all-ceramic restorations, with a total number of 164. Most of them were made from densely sintered zirconia, followed by alumina and reinforced glass-ceramic . CompareThe incidence of ceramic fracture occurred as another technical complication in 120 FPDs. Most of the fractures occurred in all-ceramic FPDs—in 51 densely sintered zirconia FPDs, 6 reinforced glass-ceramic FPDs, and one glass infiltrated alumina FPD, to be precise. Four metal-ceramic restorations were reported with ceramic fractures.Loss of retention or decementation was reported in 4 studies out of the studies included in the present review. Out of the total of 916 FPDs, 21 restorations needed recementation. The majority of these FPDs were made from densely sintered zirconia . One stuHowever, despite significant developments in adhesive protocol toward enamel and dentine, failures related to secondary caries are still a major issue when adhesive restorations are addressed. It should be considered that, prior to the appearance of secondary caries, interfacial gap formation plays an important role as it represents the first sign of restoration deterioration .The evaluated studies included in this literature review confirmed that all-ceramic restorations have similar survival rates after 3 years compared to the golden standard, the metal-ceramic FPD. The mean-survival rates after 5 years clearly show that densely sintered zirconia and reinforced glass-ceramic can compete with metal-ceramic FPDs . The difThe reinforced glass-ceramic FPDs showed survival rates of 70% to 93% at 5 years. The metal-ceramic FPDs have shown to have 3-, 5-, and 10-year survival rates of 95% to 100%. Zirconia FPDs were shown to have survival rates ranging from 81% to 100% at 3-, 5-, 10-year follow-up evaluation, while the alumina FPDs had a survival rate of 68% at 3 years. This finding is in accordance with the findings of other studies that compared the survival rates of all-ceramic and metal-ceramic FPDs ,54,55.Rinke et al.  reportedRegarding framework fractures, they occurred only in all-ceramic restorations, predominantly in alumina FPDs and densely zirconia FPDs in the present review. In this respect, Sulaiman et al. observed a low failure rate for lithium disilicate FPDs in a follow-up period of up to 7.5 years, which is in accordance with our results . Koenig An important observation of our review was that ceramic chipping was the most frequently reported complication, followed by ceramic fracture and core fracture. Chippings can be polished when they are detected early in order to prevent further worsening, which can lead to ceramic or framework fractures. The occurrence of technical complications is highly dependent on design, the all-ceramic system, as well as the cementation and present antagonists of similar materials. Loss of retention was much more prevalent in zirconia-based restorations, although the statistical outcome is not significant ,46.We take into account that most of the studies followed strict exclusion criteria when planning the trials and that not all parameters that could lead to technical complications related to the parafunctional habits were included. Patients who continued attending their follow-ups showed surprisingly good results in one of the studies, with even better results from the baseline examination . The gatFrom the evaluated studies, 3 trials on densely sintered zirconia reported survival rates of 100% after 3 and even 5 years. However, frequent check-ups and early detection of complications such as chipping, which were polished or repaired, are necessary in order to maintain a high survival rate ,46,47. FBiological complications such as secondary caries and loss of tooth vitality were more often seen in all-ceramic restorations, especially in zirconia. Similar results regarding the appearance of secondary caries have been reported by Pjetursson et al. ; thus, hFurthermore, the adhesive cementation requires multiple steps to prepare the tooth surface for restoration. Good isolation and proper etchability of the enamel/dentin are necessary. Additionally, the quality of the bond is amendable to surface conditioning, which has been proved by applying different methods of cleaning to restoration after etching. The effects of the adhesive cementation on clinical outcomes may be quite different, such as loss of vitality and the marginal discrepancies that are represented by the internal gap. Prior to clinical failure, usually considered as the debonding restoration, the internal gap is the first sign; it can lead to bacterial recolonization of the tooth crown and root tooth system and, with subsequent endodontic failure .Some of the authors ,53 have On the other hand, several studies evaluated the survival rate of all-ceramic restorations and came to results of 100% after 3 or even 5 years. However, most of these studies have excluded patients with parafunctional habits, resulting in higher survival rates . This caPractitioners have to consider many factors such as cementation, occlusion, opposed teeth of all-ceramic material, parafunctional habits, and aesthetics when planning a treatment in order to satisfy the patient’s needs. In order to ensure a high survival rate, check-ups of the restorations are essential for detecting minor chippings in time in order to keep the longevity of the restoration. Despite the limitations of our study , our data also suggest improving existing all-ceramic systems to reduce the incidence of technical or biological complications.In this literature review, most of the studies have shown similar results regarding the survival and success rates of all-ceramic and metal-ceramic FPDs. The technical and biological complications also had similar outcomes. All-ceramic and metal-ceramic restorations show similar survival rates after 3 years, although all-ceramic restorations struggle with technical complications such as chipping, which can lead to framework fractures over time.Zirconia and reinforced glass-ceramic systems proved to be able compete with the golden standard of metal-ceramic restorations. Thus, they also show promising results for the future.Alumina restorations were reported to be less promising in the posterior areas due to the increased risk of the framework fracture. Despite technical complications, all-ceramic systems showed promising results even after 5 years. However, more studies are required to strengthen the hypothesis of all-ceramic systems being a definitive alternative to metal-ceramic posterior restorations.To conclude, all-ceramic systems, especially densely sintered zirconia and reinforced glass-ceramics, have a promising future to satisfy both practitioners and patients. However, the technical and biological complications need to be taken into account when deciding to treat edentulism in the posterior areas.


In vitro microbiota models are promising tools for studies requiring controlled and repeatable conditions. We evaluated the impact of two anticancer drugs on human feces in the MiniBioReactor Array (MBRA) in vitro microbiota system.Anticancer drug efficacy is linked to the gut microbiota’s composition, and there is a dire need to better understand these interactions for personalized medicine. The MBRA is a single-stage continuous-flow culture model, hosted in an anaerobic chamber. We evaluated the effect of a 5-day treatment with hydroxycarbamide or daunorubicine on the fecal bacterial communities of two healthy donors. 16S microbiome profiling allowed analysis of microbial richness, diversity, and taxonomic changes.In this host-free setting, anticancer drugs diversely affect gut microbiota composition. Daunorubicin was associated with significant changes in alpha- and beta-diversity as well as in the ratio of Firmicutes/Bacteroidetes in a donor-dependent manner. The impact of hydroxycarbamide on microbiota composition was not significant.in vitro human microbiota model. We confirm the importance of personalized studies to better predict drug-associated-dysbiosis in vivo, linked to the host’s response to treatment.We demonstrated, for the first time, the impact of anticancer drugs on human microbiota composition, in a donor- and molecule-dependent manner in an  Cancer incidence increases yearly, with 18 million new diagnostics worldwide in 2018 and over 19 million in 2020 . AccordiThe frequent digestive symptoms reported after these treatments  support a significant alteration of the human gut microbiota, leading to drug-associated-dysbiosis; however, no studies monitored the drug concentration in the feces. Yet, though neglected for decades, this induced modification in the gut microbiota composition may have major consequences, as besides its implication in human pathology .Anticancer drugs have been developed to target cancer cells; however, they are nonspecific, and some even have well-known antimicrobial properties . For theEvidence is growing on the importance of the gut microbiota composition in the host’s response to anticancer treatment . The gutin vivo in patients receiving concomitant treatments such as anticancer drug combinations or the frequent treatment with antimicrobials.All these interactions and their potential dramatic effects on a patient’s health are calling for a deeper characterization and, particularly, a clarification of the impact of chemotherapy on gut microbiota composition. Indeed, most of the studies evaluating the impact of anticancer drugs are designed in vitro microbiota model allows the exclusion of the confounding factors associated with the gut microbiota disturbances inherent to the host or its environment  nditions  to studyFacing many anticancer drugs to test, we decided to evaluate the impact of two anticancer drugs used in leukemia and other hematologic malignancies, hydroxycarbamide and daunorubicin. To assess the direct effect of these two drugs on the human gut microbiota composition, we simulated an anticancer treatment using the MBRA model, which was inoculated with fecal samples of two health donors followed over 5 days of treatment.in vitro experiment using the MBRA system, hosted in an anaerobic chamber at 37°C, as described previously by We conducted an Human fecal samples were collected from two healthy donors belonging to the same age class (30 +/− 5 years old). None had consumed antibiotics nor had any medical issues within the previous 6 months. In agreement with the INSERM ethics regulation and with the declaration of Helsinki, all received clear information and consented. Fecal samples were directly collected in a sterile container and placed in anaerobic conditions. Within 24 h after emission, the samples were subsequently subdivided into sterile vials (under anaerobic conditions) and stored at −80°C until use.Fecal samples were processed as previously described . After aTo study the effect of anticancer molecules on gut microbiota composition, we selected among the most used molecules an anthracycline aminoglycoside [daunorubicin 25 mg/L (dauno25)]  and an a® (Qiagen) for total DNA extraction, following the manufacturer’s protocol. We collected 100 µl of frozen MBRA-fecal samples from 8 time points (I-S-T1-T2-T3-T4-T5-PT) for gut microbiota composition analysis. We subsequently used the Qiacube® High-Throughput 96-sample robot for DNA extraction.We used the DNeasy Power Soil Pro 250 kit® Index Kit and Nextera® XT Index Kit V2 Set D. PCRs products were visualized by gel electrophoresis and quantified using the Qubit HS® normalized to 4 nM for pooling and sequencing. 16S rRNA gene sequencing was performed with the Illumina MiSeq technology (paired-end reads 2 * 250 bp).Intestinal gut microbiota composition in collected samples was analyzed using 16S rRNA gene sequencing , targetivia “q2-dada2”) pipeline  and phylogeny was constructed with fasttree-2 (via “q2-phylogeny”). Alpha diversity (diversity within each chamber) was analyzed with the Shannon Index, while beta diversity (diversity between each chamber) was represented by Jaccard analysis (using “q2-diversity”).16S rRNA gene sequences were analyzed using QIIME2-2020.8 software for microbiome bioinformatics analysis . The sampipeline . The reapipeline  , p-values around 0.05 and below are reported, and minimal value is 1e−4. Because alpha diversity globally declines with time, we used time as a cofactor (treated as a factor) in the PERMANOVA. To better consider the decrease in diversity with time, we also performed a linear model with p-values estimated by permutation . We used the same approach to study beta diversity.More specifically, for alpha diversity, we estimated a relative deviation for each chamber from the before-treatment baseline. Subsequently, a Permutational multivariate analysis of variance (PERMANOVA) (function aovp from the “lmPerm R” package) was used in which Diversity analysis required the samples to be prior rarefied to 10,000 and 7,500 sequences per sample in the hydroxycarbamide and daunorubicin experiments, respectively. We assigned taxonomy to all amplicon sequence variants using a Naive Bayes classifier trained on the Greengenes reference database 13_8 (using “q2-feature-classifier”) . Rarefiein vitro human gut system, we quantified the in vitro impact of hydroxycarbamide and daunorubicin on gut microbiota composition. During the stabilization phase (S), differences between the treated and nontreated chambers  were nonsignificant (p > 0.1 for donors A or B on either drug), and all 12 chambers per donor could be considered comparable.Using the 16S microbiome profiling and the MBRA Principal coordinate analysis (PCoA) of the Jaccard matrix from all time points, all conditions, and all donors showed that the two donors could be well distinguished throughout the experiment Figure 2p-values are based on permutations .First, to study alpha diversity, a PERMANOVA was used in which p < 1e−4, p < 1e−4, and p = 0.0002, respectively)  was significant whether we pooled data from both donors, singled out donor B, or to a lesser extent when we singled out data from donor A (ctively) Figure 3p = 0.004) and an effect for donor B (p = 0.02) but no effect for donor A (p = 0.07)  Figure 3p-values estimated by permutation considering the decrease in diversity through time. Results were consistent with the first approach with an effect of daunorubicine  and a modest or lack of effect for hydroxycarbamide .Our results were confirmed by a linear model with For beta-diversity analyses, the same approach was used. We measured the Jaccard Index between the chambers before treatment and the later time points. For both drugs, results were consistent with the one observed with alpha diversity, but this time, the treatments induced a faster differentiation compared with controls.p < 1e−4, lmp: p < 1e−4 for A, B, and A and B). Hydroxycarbamide was associated with a mild effect in donor B  and the combination of donors , but not in donor A   Figure 4p = 0.23) but was marginally significant for donor A (p = 0.04).Using Bray–Curtis metrics, similar results were found. The overall effect of treatment was not found to be significant for hydroxycarbamide , in the controls, Firmicutes were dominant (55.7% of rarefied counts in donor A and 48.4% rarefied counts in donor B) with Bacteroidetes (25.0% rarefied counts in donor A and 31.5% rarefied counts in donor B) and Proteobacteria being less abundant (16.4% rarefied counts in donor A and 16.9% rarefied counts in donor B).Proteobacteria evolved comparably between the experiments and followed a constant increase through time in both donors and both molecules.In the daunorubicin group, compared with baseline (S), we observed a decrease in the Bacteroidetes phylum from T1 in donor A. In donor B, Bacteroidetes evolved similarly throughout the experiment. A decrease in Firmicutes was observed in donor B compared with the variations in the control group Figure 5p > 0.1) for both treatments. However, in both treatments, a donor-dependent effect was suggested with a signal in one of the two donors  (p = 0.03), but significant for donor A (p = 1e−4), and marginally significant for both p = 0.05. This is explained by the fact that the effect was inversed for each donor. Indeed, both had very different initial ratios, and through time, they converged towards an intermediate value. It seems daunorubicin slows down this convergence in both cases. Hydroxycarbamide showed a moderate impact for both donors . A reduction in the ratio was observed in both donors.We also calculated the change in the Firmicutes/Bacteroidetes (F/B) ratio, which is admitted as an early dysbiosis biomarker . When we= 0.004) Figure 6Relying on recent advances in oncology and the tight relation between the gut microbiota and human pathologies , we aimehttps://www.iledefrance.ars.sante.fr/media/6333/download). It is a nonalkylating antineoplastic reversible DNA replication inhibitor , widely used in the treatment of hematologic pathologies such as chronic myeloproliferative disorders and in sickle cell disease  for a PhD. The Q.E.M Team currently works with FRM funding (EQU201903007848). We also relied on the ANR GeWiEp (ANR-18-CE35-0005-0) funding for the equipment. BC’s laboratory is supported by a Starting Grant from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. ERC-2018-StG-804135), a Chaire d’Excellence from IdEx Université de Paris - ANR-18-IDEX-0001, an Innovator Award from the Kenneth Rainin Foundation, an ANR grant EMULBIONT ANR-21-CE15-0042-01, and the national program “Microbiote” from INSERM.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.


P = 0.007). The developed nomogram provided a 83% probability of estimating the post-cutting graft thickness within 25 µm. Our nomogram, which considers cause of death, enables reproducible production of graft of a desired thickness. A detailed analysis of donor tissues, including the cause of donor death and the characteristics from pressurization to cutting, will enable more precise DSAEK graft preparation.Descemet's stripping automated endothelial keratoplasty (DSAEK) is used for treating corneal endothelial dysfunction, and the postoperative visual acuity outcome depends on the thickness of the graft. We created a simple nomogram using factors affecting the cutting thickness during graft preparation via a mechanical microkeratome system for DSAEK. This retrospective study was conducted from May 2018 through October 2022 and included donor eyes cut by automatic methods. We measured the graft thickness, cutting accuracy, and assessed ten variables with donor/cornea-related factors potentially affecting the cutting thickness. Subsequently, we created a simple nomogram. We analyzed 81 donor tissues, and the donor median age was 76 years. The mean central graft thickness was 122.2 μm, with 62% of the grafts that could be cut within the target central graft thickness range. Comparatively, donor corneas from those with cardiac diseases were cut deeper ( A high-quality pre-cut donor tissue is necessary for a successful surgery and for achieving good visual acuity5. Several factors influence good outcomes following DSAEK; of these, the thickness of the graft affects the postoperative visual acuity3. A protocol to achieve the desired graft thickness without perforation should be developed to improve patient prognosis and to conserve donor corneas due to a shortage worldwide6.Descemet's stripping automated endothelial keratoplasty (DSAEK) is widely used for treating corneal endothelial dysfunction7. Manual microkeratome cutting produces grafts of variable thickness because of the difficulty in maintaining constant conditions, and its results are less reproducible9. Recently, some operators have prepared DSAEK grafts using a mechanical microkeratome system, in which a pass is automatically performed by the instrument, while a constant artificial chamber internal pressure (IP) is maintained11. Thus, we hypothesized that it was possible to identify other factors affecting the cutting thickness. We then developed an accurate nomogram to create the desired thickness grafts under fixed cutting conditions using a mechanical microkeratome system.DSAEK tissue is most often processed by a microkeratome and the cutting depth is adjusted to control the thickness of the resulting posterior lenticuleWe sought to create a simple nomogram using each microkeratome head size by examining donor/cornea-related factors affecting the cutting thickness of DSAEK graft preparation under fixed conditions of IP settings and cutting speed by a mechanical microkeratome system.2 (range 2053–3175 cells/mm2); eight grafts (10%) displayed good epithelial status before cutting, whereas 73 grafts displayed non-good status .We prepared 89 donor tissues using the mechanical microkeratome system for DSAEK during the study. All cut donor corneas showed no perforation or other complications and were used for DSAEK. Table r = 0.60 to 0.65, P < 0.01) in 350- and 400-microkeratome head sizes. Approximately 62% of the grafts could be cut within the target central graft thickness range (125 ± 25 μm); 21% of the grafts were cut to a depth shallower than 25 μm, and 17% were cut deeper.Table P < 0.001) was identified as a potential factor affecting the cutting thickness of the ten variables with donor/cornea-related factors tested in univariate analysis (Table P = 0.007). Donor corneas from those with cardiac diseases were estimated to cut significantly deeper (20.66 μm) than those with other causes of death. Eventually, the selected model was calculated as follows:In the donor corneas cut by ACP/OUP-A, the cause of death  was 122.2 μm. In addition, 350-head was the most frequently selected size  were associated with the development and severity of glaucoma18. Considering that the central donor corneal thickness before cutting did not differ for each cause of donor death  and constant IP was maintained by ACP at 200 mmHg, the affecting cutting depth can be attributed to the tissue resistance to deformation characteristics of the donor cornea  during pressurization or cutting. Corneas from donors due to cardiac death are considered to be hard in consistency and low in resilience. Our data may indicate that, during procurement of a cornea from a cardiac-death donor using a microkeratome, the angle at the blade entry point is deeper, resulting in a deeper cut to the tissue. The cause of death may reflect the condition of the cornea rather than an independent biomarker. Further detailed data/analysis are needed because potentially include factors not addressed in this study as confounding factors. Donor corneas used for cutting are processed onto the sclerocorneal button, thus making it difficult to determine their biomechanical characteristics. Therefore, changes in the shape in response to the IP have not been studied. The measurement and understanding of the shape of tissue resistance to deformation characteristics of the donor cornea under IP with instruments, such as the Ocular Response Analyzer19 will further improve the cutting accuracy in the future.We identified the cause of death as a factor affecting the cutting depth in the preparation for DSAEK graft under fixed conditions. Predicting graft thickness after cutting with a model adjusted for donor cause of death provided about a 20% 62% to 83%) improvement in the theoretical probability of a target range compared to predicting with only donor corneal thickness Figs. , 3. Ther% improve20. The developed nomogram indicated that the older the donor, the deeper the cut. Moreover, our findings revealed a tendency for older donors to have deeper cuts; nonetheless, there was no statistically significant difference in the depth of cut by donor age. The age-adjusted nomogram could predict the thickness to be within 25 μm 80% of the time, like the accuracy level of our nomogram that adjusted for the cause of death  may also be possible in our developed nomogram. However, considering that our nomogram had an 7% risk of cutting 25 μm deeper and a maximum difference of cutting 44.0 μm deeper than that predicted value . Second, there is no standard method for measuring the thickness of the donor cornea. Several institutions measure the corneal thickness before/after cutting with a pachymeter, and not anterior segment optical coherence tomography. An accurate installation of the developed nomogram warrants understanding differences between the measurement devices. Third, our sample size was relatively small. An accurate modeling requires the consideration of several variables and a larger sample size.In conclusion, the cause of death  affected the cutting depth under fixed settings with a mechanical microkeratome system. It is possible to achieve 83% probability of producing grafts within ± 25 m of the target thickness using the nomogram that predicted the post-cut central graft thickness from the central donor corneal thickness for each microkeratome head size and cause of death (cardiac/non-cardiac disease). Furthermore, a detailed analysis of donor tissues, including the cause of donor death and characteristics from pressurization to cutting will enable an accurate DSAEK graft preparation. This, in turn, would likely optimize the use of limited donor resources and improve patient outcomes.This single-center retrospective study was conducted from May 2018 through October 2022, with donor eyes cut by the mechanical microkeratome system at CCEB, Chiba, Japan. All donor corneal tissues were of domestic origin and donated to CCEB, preserved in a viewing storage chamber, and retained in a cold-storage corneal preservation medium . All eligible donor corneas prepared for DSAEK met the medical standards of CCEB. This study was conducted according to the tenets of the Declaration of Helsinki and was approved by the Institutional Ethics Reviewer Board of the Tokyo Dental College Ichikawa General Hospital (Acceptance No. I 22-07). The need to obtain informed consent directly was waived; however, study participants were able to decline participation using an opt-out method. All data were anonymized before access and/or analysis.10. Briefly, for the ACP/OUP-A automatic protocol, we set the initial IP at 200 mmHg and constantly maintained it with ACP during the microkeratome cut. The target central graft thickness was 125 ± 25 μm. We selected the microkeratome head size within 300-, 350-, 400-, and 450-head sizes based on the central donor cornea thickness aiming for a target central graft thickness. Typically, we adapted the 300-, 350-, 400-, and 450-head in case of central donor corneal thickness < 499 μm, 500 μm–549 μm; 550 μm–599 μm; and > 600 μm, respectively. OUP-A was set on an artificial chamber and the pass was automatically performed by the instrument, with a forwarding speed of 3.0 mm/s by selecting a “speed 2” on the Evolution 3E control unit (Moria). An experienced technician (SN) performed all cutting using a single-pass technique in a laminar flow cabinet with a new disposable blade for each donor. Following cutting, the separated anterior lamella cap was replaced onto the cornea and returned to the viewing chamber filled with the cold-storage corneal preservation medium. We measured the central corneal thickness before and after the microkeratome cut using anterior segment optical coherence tomography 27. Each corneoscleral donor tissue was scanned through the transparent window of the corneal viewing chamber, without removing them from the storage medium. The chamber was held on the chinrest by a custom-built attachment, with the mounted cornea facing the image capture lens. Images were obtained along two meridians  in manual mode. The distances from the endothelial surface to the top epithelial surface and the top of the cutting line was measured to determine the center point of each corneal image. The corneal center and graft thicknesses were measured at this center point and the mean values were subsequently calculated. This two-dimensional analysis was performed in manual mode using the scale in the image analysis software. We calculated the cutting depth by subtracting the thickness before and after the cut at the center. All tissues were evaluated for ECD and transplant suitability  using slit-lamp microscopy performed by ophthalmologists before DSAEK.All donor tissues were stored at 4 °C and returned to room temperature before the microkeratome cut. The tissues were dissected by the mechanical microkeratome system using an artificial chamber pressurizer  and one use-plus automated 29 that could potentially affect the cutting thickness: age, sex, a history of diabetes mellitus, lens status (phakic/intraocular lens [IOL]), cause of death (cancer/cardiac disease/cerebrovascular accident/other diseases), time from death until preservation, time from death until cutting, ECD, graft epithelial status (good/non-good), and graft endothelial folds (none/mild/moderate). Using the extracted factors, we constructed a model to predict the post-cut graft thickness from the donor corneal thickness and microkeratome head size to create a simple nomogram. A cut graft thickness model was created by randomly selecting 81 eyes, and the remaining 8 eyes were used to evaluate the accuracy of the created model.We tabulated the central donor corneal thickness and central graft thickness by the microkeratome head size and created scatter plots. We calculated the cutting accuracy as the percentage of corneas that could be cut within the target thickness range or those cut in other ranges . We selected the following ten donor/donor cornea-related factorsn = 50) since the variation in graft thickness was dependent on the cutting method29. An effect size of 0.61 (Cohen’s d) was estimated to detect a difference of more than 20 μm in the thickness of the cut graft by donor/donor cornea-related factors. In the linear mixed-effects model with two clusters, a sample size of approximately 81 observations was sufficient to achieve 80% power to detect effect size of Cohen’s d = 0.61 at an alpha level of 0.05. We assessed the normality of data using the Shapiro–Wilk test and a normal Q-Q plot. We estimated the Pearson's correlation coefficient for the relationship between the central donor corneal thickness and central post-cut graft thickness. Potential donor/donor cornea-related factors affecting the cutting depth were identified based on a univariate analysis with the outcome of cutting depth being deeper or shallower than the mean thickness (P < 0.05). In this analysis, the collected categorical data were transformed into a dummy, and continuous variables were dichotomized with the mean/median for use as categorical data. We used a linear mixed-effect model to predict the post-cut graft thickness30, with the central donor corneal thickness and microkeratome head size (fixed effect) adjusted for potential donor/donor cornea-related factors (random intercepts) that affected the cutting depth. The variance estimation method was restricted maximum likelihood, and the regression model was selected using Akaike's information criterion with a P < 0.05 as the variable selection criterion. Statistical analyses for cutting accuracy were conducted using STATA/IC 16.0 for Windows . We used R version 4.2.1 for Windows  for the sample size calculation in a linear mixed-effect model (sjstats package) and for thickness modeling (lme4 package). All reported P-values were two-sided, and values < 0.05 were considered statistically significant.The effect size estimates were calculated using pilot cut data (Supplementary Figure 1.


Nature,1 Iram et al. are the first to identify fibroblast growth factor 17 (Fgf17) from the young mice cerebrospinal fluid (YM-CSF) as a key molecule to improve cognitive functions in aged mice by driving the proliferation and differentiation of oligodendrocyte progenitor cells (OPCs), indicating that effective remyelination induced by young CSF factors may provide a novel and promising therapeutic strategy to rejuvenate the ageing brain, which again confirms that factors present in the young tissue can serve as therapies in ameliorating ageing-related symptoms.In a recent article published in 2 However, the recently developed concept of brain active milieu suggests that the brain functions are determined by orchestrated interactions among neurons, glia, non-neuronal cells, and non-cellular elements.3 Thus, senescence of all elements of the active milieu can play a role in brain ageing. For example, we recently showed that astrocytic dystrophy parallels the impairment of synaptic plasticity in old brains.4 In addition, oligodendrocytes and they produced myelin sheaths have also been shown to play crucial roles in learning and memory,2 because a long-range signaling in the brain that relies on myelin functions and mature oligodendrocytes are important for the maintenance of axonal health and for regulation of neuronal function. Therefore, myelin degeneration and diminished myelin renewal contribute to ageing-related deficits in memory.5 An interesting finding showed that myelination is very intense in young mice and is greatly inhibited in aged mice, coinciding with spatial memory deficits.5 Unfortunately, the detailed reasons of the marked differences in myelin regeneration between young and old remains unclear. As we know, myelin remodeling in brain is primarily orchestrated by mature oligodendrocytes, which are derived from OPCs’ differentiation. Therefore, maintaining the dynamic balance between OPCs and oligodendrocytes during aging to promote effective myelin remodeling could be beneficial for improving ageing-related symptoms.People have been searching for the secret of longevity since ancient times, but no breakthrough has been made to date. However, leaving aside the question of whether longevity is feasible, there is an urgent need to resolve the issue of ageing-related health deterioration. For example, cognitive decline remains an unsolved issue for the elderly. The senescence of neurons has long been considered as a major cellular mechanism of such decline.In this study, Iram et al. first tested whether administration of young CSF to aged mice via intracerebroventricular (ICV) would effectively rejuvenate the brain. When age-related cognitive decline  was reversed by YM-CSF, they investigated the cellular and molecular changes in hippocampus with bulk RNA sequencing (RNA-seq). They found that highly upregulation of transcription factors driven by YM-CSF were involved in promoting oligodendrocyte differentiation and major myelin protein components. Given that the OPCs are the initiating myelination process, their growth was assessed in the aged hippocampus and in primary OPC cultures. The results showed that YM-CSF enhances OPC proliferation and differentiation both in in vivo and in vitro. These results suggest that young CSF contains rejuvenating factors that promote cell growth for the oligodendrocyte lineage or neutralize inhibitory factors.Next, to gain a deeper mechanistic insight into the cell growth for OPCs induced by YM-CSF, nascent mRNAs from cultured OPCs 1 or 6 h after exposure to young human CSF (YH-CSF) were metabolically labeled with 4-thiouridine (s4U) and then detected by thiol (SH)-linked alkylation for the metabolic sequencing of RNA (SLAMseq). The results of this experiment showed that many of the differentially expressed genes peaking at 6 h after YH-CSF exposure are known as serum response factor  target genes. The most strongly upregulated genes were enriched for “target genes of SRF”. The following experiments demonstrated that the suppression of the OPC proliferation and differentiation in the aged brains was caused by the depressed SRF signaling pathway in OPCs, which was reactivated in vivo by young CSF treatment. Therefore, these experiments indicate that SRF signaling in OPCs is inhibited with ageing and may serve as a therapeutic target against the ageing-related deficits.Because the source and quantity of CSF may be the most critical factors restricting its widespread application in clinical practice, revealing the active components of CSF can address this issue. Then, based on the observation of SRF signaling pathway, two published CSF proteomic datasets were cross-referenced with the predicted SRF targets, which generating a list of 35 potential SRF inducers. Among them, Fgf17 gained the favor of researchers because it is a brain-enriched protein, and its levels decrease with age in human plasma, CSF and mouse neurons. It also induced the strongest dose-dependent activation of SRF. In addition, Iram et al. found that Fgf17 activates SRF signaling through actin modulation by enhancing or inhibiting actin polymerization using jasplakinolide and latrunculin A, respectively. In vitro experiment showed that Fgf17 induces OPC proliferation and differentiation when primary rat OPCs exposure to Fgf17. To further confirm these effects observed in in vitro, the aged mice received 1 week of infusion with Fgf17 showed markedly increased OPC proliferation in the aged hippocampus and improved long-term memory performance. In contrast, blocking Fgf17 in young mice showed impaired performance and impaired neuronal plasticity, suggesting that Fgf17 is necessary for normal memory function. These results strongly demonstrate that Fgf17 is sufficient to activate OPCs in the hippocampus and consolidate memory in aged mice, which was comparable to the effects of young CSF.Iram et al. have provided solid evidence that young CSF is capable of restoring memory in aged mice via Fgf17 at the OPCs (Fig.


We developed a pragmatic dichotomous grading criterion to stratify the acute tubular injury (ATI) of deceased-donor kidneys. We intended to verify the predictive value of this criterion for the prognosis of deceased-donor kidney transplantation.The allografts with ATI were classified into severe and mild groups. Severe ATI was defined as the presence of extreme and diffuse flattening of the tubular epithelial cells, or denudement of the tubular basement membrane. The clinical delayed graft function (DGF) risk index was calculated based on a regression model for posttransplant DGF using 17 clinical parameters related to donor–recipient characteristics.2, p < 0.001), 3 months , and 6 months after transplant . However, there was no significant difference in eGFR at 1 year or beyond, graft, and patient survival. The predictive value of combined dScr with ATI severity for DGF rate and DGF recovery time was superior to that of dScr alone. The predictive value of the combined DGF risk index with ATI severity for DGF was also better than that of the DGF risk index alone; however, the association of the DGF risk index with DGF recovery time was not identified. Chronic lesions including glomerulosclerosis, interstitial fibrosis, arterial intimal fibrosis, and arteriolar hyalinosis were associated with declined posttransplant 1-year eGFR.A total of 140 recipients were enrolled: 18 severe and 122 mild ATI. Compared with the mild ATI group, the severe ATI group had more donors after cardiac death, higher median donor terminal serum creatinine level (dScr), and longer median cold ischemia time. Severe ATI had a higher DGF rate , longer DGF recovery time , and a lower estimated glomerular filtration rate (eGFR) at 1 month (23.5 vs 54.0 ml/min/1.73 mBased on our pragmatic dichotomous grading criterion for ATI in a preimplantation biopsy, donor kidneys with severe ATI increased DGF risk, prolonged DGF recovery, and decreased short-term graft function but demonstrated favorable long-term graft function. Our grading method can offer additive valuable information for assessing donor kidneys with acute kidney injury and may act as an effective supplementary index of the Banff criteria. Kidney transplantation is the best treatment for patients with irreversible chronic kidney failure . An incrKidneys with acute kidney injury (AKI) from deceased donors are considered marginal donor kidneys –10. SeruAnother method to identify and quantify donor AKI is pretransplantation renal biopsy –34. All We retrospectively reviewed the medical records of adult (≥18 years old) kidney transplant recipients who received deceased-donor kidneys, including organ donation after brain death (DBD) and donation after circulatory death (DCD), in which a pretransplantation donor kidney biopsy was performed, at the First Affiliated Hospital of Sun-Yat Sen University from Jan 2012 to June 2017. Recipient and donor demographic, clinical, and pathological data were extracted from the medical records of the follow-up database. These recipients were followed up until 2021. This study was approved by the Institutional Review Board of the hospital, and because of the retrospective nature of the study, the requirement of informed patient consent was waived. No organs from executed prisoners were used.Biopsies were performed immediately before implantation by using a 16-gauge biopsy needle. The biopsy was performed at the superior edge of the donor kidneys, and two cores of tissue were obtained. Frozen sections of one core were stained with H&E and examined to determine whether to use or discard the kidney. Multiple frozen sections were also saved for subsequent immunofluorescence stains for immunoglobulin and complements including IgG, IgM, IgA, C3, and C1q. The other core and the rest of the frozen tissue were fixed, paraffin-embedded, and stained with H&E, periodic acid–Schiff (PAS), periodic Schiff-methenamine silver (PASM), and Masson’s trichrome (MASSON). Stained biopsy specimens were examined retrospectively by 2 experienced pathologists for a comprehensive assessment of glomerular, tubular, interstitial, and vascular lesions in the donor kidneys.Donor kidneys with tubular coagulative necrosis and parenchymal infarction were excluded from the study. The recipients enrolled were classified into 2 groups based on whether or not the pretransplantation renal biopsy showed severe ATI Figure 1The patients were divided into high and low donor serum creatinine groups based on donor terminal serum creatinine levels, with a cutoff value of 176.8 µmol/L (2 mg/dl). The high creatinine group was roughly equivalent to stage 2 and 3 AKI according to the KDIGO criteria . To asseClinical prediction models are also a means to assess the prognosis of AKI donor kidneys, and we have previously validated models published internationally , with thMeasures of short-term posttransplantation allograft function were the occurrence of DGF, DGF recovery time, and estimated glomerular filtration rate (eGFR) at 3 and 6 months. Long-term graft function was evaluated by eGFR at 1–3 years after transplantation and death censored graft survival and patient survival. Glomerular filtration rate was estimated using the Modification of Diet in Renal Disease (MDRD) Study formula . If the We also collected posttransplant indication renal allograft biopsy results from the patients with severe ATI to observe the pathological change of renal tubular injury at different times after surgery to demonstrate AKI recovery.Continuous data with normal distribution were presented as mean ± SD and compared using Student’s t-test. Continuous data without a normal distribution were expressed as median (interquartile range [IQR]) and compared using the Mann–Whitney U test. Categorical data were reported as counts and percentages and compared using a chi-square test or Fisher’s exact test. Comparison of continuous data among multiple groups was performed using one-way ANOVA or the Kruskal–Wallis test. Logistic regression and linear regression were used for univariate and multivariate analyses. The likelihood-ratio test was used for the comparison of model performance. All statistical tests were 2-sided, and values of p < 0.05 were considered to indicate statistical significance. Statistical analyses were performed with R software (version 3.6.1).A total of 140 recipients were included in the analysis with a median follow-up time of 4.0 (IQR 3.1–5.0) years. Eighteen of the recipients received donor kidneys with severe ATI identified on pretransplantation biopsy, and 122 received kidneys with mild ATI Table 1.Compared with the grafts with mild ATI, those with severe ATI had a significantly higher DGF rate, longer DGF recovery time, and a lower eGFR at 1, 3, and 6 months after transplant Table 2.2, p < 0.001) . The predictive ability of combined donor creatinine level with ATI severity for DGF was significantly better than that of donor creatinine level alone  or that of ATI severity alone (p = 0.037)  Table 4.We also evaluated the effect of chronic pathological changes  in the pretransplant biopsy on the allograft outcome 6. The eNine of the patients with severe ATI underwent 13 postoperative allograft biopsies, and the biopsy was performed from 2 weeks to 1 month posttransplant in 9 cases, 2 months in 2 cases, and 6 months in 2 cases. The pathological manifestations associated with renal tubular injury were described as tubular epithelium flattening, denudement of TBM, tubular cell calcification, granular cast, and regenerative changes. From 2 weeks to 1 month posttransplant, there was some degree of recovery from renal tubular injury, with severe lesions still present (denudement of TBM 22.2%) Table 7,In this study, we developed a pragmatic pathological grading criterion for ATI. Severe ATI compromised short-term posttransplantation graft function; severe ATI was associated with an increased DGF rate, prolonged DGF recovery time, and lower eGFR before 6 months posttransplant. However, the kidney allograft function at 1 year and beyond posttransplant and the graft survival was not related to the severity of ATI. It was noteworthy that the performance of the prediction model for DGF including both donor creatinine and ATI severity was the best among all prediction models.Long-term graft kidney function was closely related to the preexisting chronic lesions of the donor kidneys . By analyzing the biopsy results at different times posttransplant, we found that at 2–4 weeks posttransplant, the donor kidney transplanted in the recipient still showed significant tubular injury but started to recover as regenerative change occurred. By 6 months posttransplant, the manifestations of renal tubular injury were almost absent. This reflected that severe ATI can be successfully recovered, and thus renal function can gradually return to normal. These results suggested that donor kidneys with ATI and no chronic lesions for renal transplantation have a good long-term prognosis, which is similar to the findings of previous studies . HoweverOur results indicated that ATI was associated with DCD status and cold ischemia time. This finding may be explained by the mechanisms by which ATI develops. ATI in a donor kidney is primarily the result of hypoxic–ischemic damage and nephrotoxic insults , 21, 23.Prior studies that have examined whether or not ATI was related to DGF have provided conflicting results. We identified several studies that focused on the association of DGF and ATI or ATN , 33, 35.Assessment of the donor kidneys with donor terminal serum creatinine or model prediction scores could only distinguish whether DGF would occur, but was not well enough to distinguish whether DGF recovery was fast or slow. The relationship between ATI severity and DGF recovery time has been poorly studied in the past. We have previously found a correlation between DGF recovery time and poor prognoses such as rejection, infection, or kidney allograft failure . In the Our results showed that pretransplantation biopsy could provide additional valuable information to the quality assessment of the donor kidneys. First, severe ATI combined with high donor terminal serum creatinine was associated with a higher risk of DGF occurrence and a longer recovery time from DGF compared with high donor terminal serum creatinine alone. The model predictive ability of combining either donor serum creatinine level or calculated DGF risk with ATI severity for DGF rate was also better than that of donor serum creatinine level or calculated DGF risk alone. ATI severity can well predict DGF recovery time, while donor serum creatinine level or calculated DGF risk is not that effective. Therefore, the combination of clinical and pathological information allows for a comprehensive assessment of AKI in the donor kidneys. Second, a part of donor kidneys with low terminal serum creatinine will have severe tubular damage, possibly due to other factors such as ischemia during the process of dying, interventions during donor procurement, and damage during organ transportation and preservation. Acute injury to donor kidneys may not be identified in these donors if a pretransplant biopsy is not performed. Third, the chronic lesions in the donor kidneys could be evaluated in the biopsy, which were associated with the long-term allograft function in our study and prior studies . TherefoWe chose extremely and diffusely flattened renal tubular epithelial cells or denudement of TBM when developing the criteria for ATI severity for the following reasons. First, these manifestations can be easily identified in the frozen section. Second, a quick diagnosis is required in pretransplant donor kidney biopsy, so the simpler and more practical the criteria, the better. Third, a previous study on the relationship between different ATI pathological descriptions and the severity of clinical AKI found that only simplification (defined as flattened tubular cell cytoplasm with complete loss of brush border), mitosis, and cell sloughing (defined as a free-floating cell in the tubular lumen without attachment to adjacent cells or basement membrane) were able to independently predict severe AKI . This waIn our cohort, severe ATI appeared slightly worse in long-term eGFR compared to mild ATI, but not statistically significant. Kidney allograft fibrosis is an important cause of late graft loss, and previous studies suggest that ATI may be associated with renal fibrosis by combined mechanisms . WhetherThis analysis is limited by its retrospective nature and may be subject to selection bias, as the choice of donor kidney biopsy before transplantation was subjective and at the surgeon’s discretion.In summary, based on our pragmatic dichotomous (mild-to-severe) grading criterion for ATI in a preimplantation biopsy, kidney allograft with severe ATI increased the risk of DGF, prolonged the DGF recovery time, and decreased the short-term graft function but demonstrated favorable long-term graft function. ATI severity in combination with donor terminal serum creatinine level performs better in predicting DGF occurrence compared with either ATI severity or donor terminal serum creatinine level alone. Pretransplant biopsy offered additive and valuable information in the assessment of AKI in the donor kidneys.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the Institutional Review Board of the First Affiliated Hospital of Sun-Yat Sen University. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.JW, JQL, WW, and HZ designed the study, analyzed the data, and co-wrote the paper. SY and WC assessed the biopsies. LL, QF, JL, RD, CW, and WZ: performed data acquisition and interpretation. HZ, WW, XC, and SL performed the statistical analyses. HZ, HM, and WC supervised the research and critically reviewed it. All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.This study was supported by the Science and Technology Planning Project of Guangdong Province, China , National Natural Science Foundation of China , Key Scientific and Technological Program of Guangzhou City (201803040011), Guangdong Basic and Applied Basic Research Foundation (2020A1515010884), Guangdong Natural Science Foundation (2018A030313016), Clinical Research 5010 Programme of Sun Yat-Sen University, Guangdong Provincial Key Laboratory on Organ Donation and Transplant Immunology , and Guangdong Provincial International Cooperation Base of Science and Technology .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 pathological value of the TT-TG distance was 13.0 mm. Each TT-TG distance revealed a significant OR with regard to PD. Conclusion: The TT-TGa, TT-TGs, and TT-TGp distance can be reliably measured by MRI even in patients with trochlear dysplasia. While the TT-TGp distance may overestimate the lateralization deformity of the tibial tubercle. Posterior femoral condylar dysplasia may be a reason for such overestimating. These findings have not been correlated to clinical outcomes and further studies are required.Background: The tibial tubercle to trochlear groove (TT-TG) distance is currently considered as an indication for tibial tubercle osteotomy. While the influence of femoral condylar morphology on such measurement remains unclear. Methods: A total of 86 patients with patellar dislocation (PD) and 86 healthy individuals were enrolled. Femoral condylar morphology and the TT-TG distance measured by anatomical transepicondylar axis (TT-TGa), by surgical transepicondylar axis (TT-TGs), and by posterior condylar reference line (TT-TGp) were assessed by MRI. Unpaired t-test, Spearman, and Pearson correlation analysis were conducted. We determined the pathological value of the parameters and established a binary regression model. Results: The interclass correlation coefficients of all the TT-TG distances were greater than 0.75 in all types of trochlear dysplasia. The lateral/posterior femoral condyle was shorter and the medial/posterior condyle was longer in the study group  than in the control group . In the study group, the TT-TGp distance was greater than TT-TGs and TT-TGa distance ( Patellar dislocation (PD) is a common disease of sports injuries . PatientThe value of the TT-TG distance more than 20 mm is considered an indication for the tibial tubercle medialization osteotomy, and if patella alta appears simultaneously, the tibial tubercle distalization should also be considered (TTO) . But theThe tibial tubercle to posterior cruciate ligament (TT-PCL) distance and the tibial tubercle to Roman arch (TT-RA) distance were depicted by researchers because of their independence from trochlear dysplasia ,16. The The transepicondylar axis has been proven to be a reliable and constant reference line on the distal femoral condyles , consistGiven the insufficient knowledge in the literature, the purpose of this study was (1) to verify the reliability of the TT-TG distance measured by PCRL, SEA, and AEA on MRI, (2) to validate the diagnostic capacity of each parameter for PD, (3) to define the difference among the three TT-TG distances in patients with PD.This study was approved by the ethics committee of our hospital. Patients diagnosed with PD from 2016 to 2021 in our hospital were selected from the Electronic Medical Record System. The inclusion and exclusion processes were conducted by two experienced orthopedic surgeons. A total of 106 patients were considered eligible for inclusion in this study according to the inclusion criteria: patients diagnosed with unilateral recurrent PD; patients with skeletal maturity; patients with MRI scans of the ipsilateral knees. Patients who met at least one of the following criteria were excluded: patients missing standard or clear MRI scans of the knees (n = 15); patients with a history of bone fracture or surgery that may influence the reliability of the measurements (n = 3); patients with severe epiphysitis of the femur (n = 2). Consequently, 86 patients were designated as the study group.Then, 86 individuals matched by age and sex with knee MRI showing neither pathology, meniscal nor cruciate ligament injury were assigned as control group in this study. The informed consent was waived by the hospital ethics committee. Medical history inquiries of all the individuals in the control group were conducted by a junior orthopedist and the MRI were evaluated by a senior orthopedist to ensure their eligibility for this study. None of these subjects had symptoms or objective pathologic findings related to the patellofemoral joints.The MRI examinations were performed within one week prior to surgical planning in patients with PD. All examinations were performed with the same 1.5T MRI scanner . All the participants were placed in the supine position with the leg in full extension and the foot in a neutral position. The target knee was secured in the multichannel 89 phased-array knee coil, and the scan range was centered on the tibia and included the entire knee joint. The coronal and sagittal planes were scanned with the T1-weighted turbo spin-echo (TSE) sequence and proton density (PD) TSE with the fat-suppressed (FS) sequence, and the axial plane was scanned with the PD-TSE-FS. The layer thickness was set to 4 mm, the slice gap was 0.5 mm, the field of view (FOV) was 160 mm, and the matrix size was 512 × 512.All the parameters were assessed on MRI slices by a senior orthopedist and a junior orthopedist in a blinded and randomized fashion using the picture archiving and communication system (PACS). To standardize the measurements, the observers met as a group and agreed upon the measuring methods. If a major dispute of the measuring result was presented, especially the degree of trochlear dysplasia, a discussion would be conducted until consensus was reached.The TT-TG distance using PCRL as the reference line was measured on the MRI scan according to the method described by Friedman et al. . The mosTo assess the posterior femoral condylar morphology, we measured the distances between the SEA and the posterior cartilaginous margin of the medial femoral condyle (MPD) and the lateral femoral condyle (LPD) on the same distal reference axial MRI slice used to define the deepest portion of the trochlear groove . The traSharma et al.  depictedt-test and Mann–Whitney U test were conducted to assess the differences in the anatomical parameters between the groups. Pearson and Spearman correlation analyses were used to verify the relationships between these parameters in the study group. Receiver operating characteristic curves (ROC) and the areas under the curves (AUC) were analyzed to evaluate the diagnostic capacity of the parameters for PD via GraphPad Software . An AUC greater than 0.7 indicates fair to good capacity [Another orthopedist conducted all the analysis independently using the average value of the parameters measured by the two observers via the SPSS software . Those length parameters were normalized by TEW to reduce individual differences. The Shapiro–Wilk normality test was performed to verify the distribution of these parameters. Then independent capacity . The datcapacity . We defiWe conducted the Post hoc analysis via G-Power software . For the effect size of 1.08 according to the TT-TGs between the two groups, a power of 1.00 was calculated .This study included 86 patients with PD in the study group and 86 healthy individuals in the control group. The demographic data of the two groups are shown in p < 0.001). The LPD/TEW was smaller in patients with PD (28.5 ± 3.3%) compared to that in healthy subjects (30.9 ± 2.7%), in contrast, the MPD/TEW was larger in the study group (35.2 ± 2.8%) compared to controls (33.5 ± 2.3%). Then the ratio of LPD/MPD was 81.3 ± 6.6% in the study group and 92.3 ± 5.2% in the control group (p < 0.001). The PCA were larger in patients with PD compared to that in the control group (p = 0.005). Trochlear dysplasia was presented in patients with PD: four (4.6%) patients with normal, 24 (27.9%) patients with mild, 20 (23.2%) patients with moderate, and 38 (44.2%) patients with severe trochlear dysplasia (p < 0.001), and the TT-TGp/TEW was greater than TT-TGs/TEW and TT-TGa/TEW (p < 0.001) , and likewise the TT-TGs and TT-TGa distance. The ratios of TT-TG distances/TEW were larger in the study group compared to that in the control group (ysplasia . In the < 0.001) .p < 0.001). But the correlations between the TT-TG parameters and the measurements of femoral condylar morphologies did not show statistical significance  . Dejour We also analyzed the diagnostic efficacy of each TT-TG distance for PD and found that the TT-TGp distance had a good diagnostic capacity, with an AUC of 0.811, which was almost equivalent to the results reported by Xu et al., (AUC = 0.820) . While tWe set the pathological value of all the three TT-TG distances measured on MRI slices at 13.0 mm in our study. Moreover, 0.6 mm discrepancy was identified when compared with previous literature (13.6 mm) , which mPrevious studies have shown that when a pathological TT-TGp distance is presented, the risk of PD would increase 5–14 times ,14,34,35We acknowledged some limitations to this study. First, we did not correlate the operation outcomes following TTO with this new pathological threshold value of each TT-TG distance that we established. Second, the subjects in the control group of this study were not completely normal individuals, but they did not have anterior knee pain, patellar instability, or other symptoms in terms of patellofemoral joints. Pathological values calculated from this sample may change in a relatively large healthy population. Third, this study only included one measuring method of evaluating posterior femoral condylar morphologies, other anatomical parameters, such as lateral femoral condyle index and lateral condyle index were not analyzed. Fourth, only two observers measure the anatomical parameters may lead to biases and the power dynamic between the senior and junior orthopedist may result in bias when there are discrepancies, and the intra-observer reliability of each parameter was not analyzed. Fifth, these anatomical parameters were only measured by MRI, CT images and radiographs should also be investigated.The TT-TGa, TT-TGs, and TT-TGp can be reliably measured by MRI even in patients with trochlear dysplasia. While the TT-TGp distance may overestimate the lateralization deformities of the tibial tubercle, posterior femoral condylar dysplasia may be a reason for such overestimating. These findings have not been correlated to clinical outcomes and further studies are required.