Ensemble Machine Learning for Predicting 90-Day Outcomes and Analyzing Risk Factors in Acute Kidney Injury Requiring Dialysis.

Purpose: Our objectives were to (1) employ ensemble machine learning algorithms utilizing real-world clinical data to predict 90-day prognosis, including dialysis dependence and mortality, following the first hospitalized dialysis and (2) identify the significant factors associated with overall outcomes. Patients and Methods: We identified hospitalized patients with Acute kidney injury requiring dialysis (AKI-D) from a dataset of the Taipei Medical University Clinical Research Database (TMUCRD) from January 2008 to December 2020. The extracted data comprise demographics, comorbidities, medications, and laboratory parameters. Ensemble machine learning models were developed utilizing real-world clinical data through the Google Cloud Platform. Results: The Study Analyzed 1080 Patients in the Dialysis-Dependent Module, Out of Which 616 Received Regular Dialysis After 90 Days. Our Ensemble Model, Consisting of 25 Feedforward Neural Network Models, Demonstrated the Best Performance with an Auroc of 0.846. We Identified the Baseline Creatinine Value, Assessed at Least 90 Days Before the Initial Dialysis, as the Most Crucial Factor. We selected 2358 patients, 984 of whom were deceased after 90 days, for the survival module. The ensemble model, comprising 15 feedforward neural network models and 10 gradient-boosted decision tree models, achieved superior performance with an AUROC of 0.865. The pre-dialysis creatinine value, tested within 90 days prior to the initial dialysis, was identified as the most significant factor. Conclusion: Ensemble machine learning models outperform logistic regression models in predicting outcomes of AKI-D, compared to existing literature. Our study, which includes a large sample size from three different hospitals, supports the significance of the creatinine value tested before the first hospitalized dialysis in determining overall prognosis. Healthcare providers could benefit from utilizing our validated prediction model to improve clinical decision-making and enhance patient care for the high-risk population.

Characterization of T-Cell receptor repertoire in immunoglobulin a nephropathy.

Immunoglobulin A nephropathy (IgAN) is an autoimmune disease characterized by abnormal IgA deposition in glomerulus. Current diagnosis of IgAN still depends on renal biopsy, an invasive method that might increase the risk of clinical outcomes. Therefore, we aimed to explore the characteristics of T cell repertoire in IgAN from peripheral blood samples for identifying innovative diagnostic biomarkers. Herein, we included 8 IgAN patients, 25 non-IgAN patients, and 10 healthy controls in the study. A high-throughput immune repertoire sequencing was conducted to investigate the T-cell receptor beta-chain (TCRß) repertoire of peripheral blood. Characteristics of TCRß repertoire were assessed for these three distinct groups. A reduced TCRß repertoire diversity was observed in IgAN patients compared to non-IgAN and healthy individuals. A skewed distribution toward shorter TCRß complementarity determining region (CDR3) length was found in non-IgAN relative to IgAN patients. In addition, the differences in usages of five TRBV genes (TRBV5-4, TRBV6-4, TRBV12-1, TRBV16, and TRBV21-1) were identified between IgAN, non-IgAN, and healthy subjects. Of note, the TRBV6-4 gene, which is associated with mucosal-associated invariant T (MAIT) cells, exhibited higher usage in IgAN patients, suggesting potential importance of MAIT cells in IgAN. In short, our findings supported TCR repertoire characteristics as potential biomarkers for IgAN diagnosis.

Renal outcomes after contrast exposure in patients with diabetes who use sodium-glucose cotransporter 2 inhibitors.

BACKGROUND: Contrast-induced nephropathy has become increasingly prevalent as the age and prevalence of comorbidities in the general population have increased. Most cases of contrast-induced nephropathy are reversible; however, some may progress to acute kidney disease, and subsequently, to chronic kidney disease. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are known for their renoprotective effects. However, whether the use of these inhibitors affects the risk of contrast-induced kidney injury remains unclear. METHODS: Data were collected from the Taipei Medical University Clinical Research Database. We included patients with diabetes who had contrast exposure between 2016 and 2020 because of computed tomography or coronary angiography. The primary outcome was the risk of a major adverse kidney event (MAKE), which encompassed acute kidney disease, chronic kidney disease progression, and the need for renal replacement therapy. Overlap weighting was performed to reduce the effects of potential confounders. RESULTS: This study included 12 421 patients, who were divided into two groups: SGLT2i users (n = 920) and nonusers (n = 11 501). The follow-up period after contrast exposure was 6 months. The risk of a MAKE was lower in SGLT2i users than in nonusers (incidence, 36.9 vs. 49.9 per 1000 person-months, respectively; P = .0011). Furthermore, the incidence of acute kidney disease or chronic kidney disease progression was significantly lower in the SGLT2i users than in nonusers. However, no significant between-group difference was noted in the incidence of other MAKEs. CONCLUSIONS: SGLT2i may be safely used in diabetic patients needing contrast exposure. The risk of a MAKE may be lower in SGLT2i users than in nonusers.

Multiplexed Antibody Glycosylation Profiling Using Dual Enzyme Digestion and Liquid Chromatography-Triple Quadrupole Mass Spectrometry Method.

Antibody glycosylation plays a crucial role in the humoral immune response by regulating effector functions and influencing the binding affinity to immune cell receptors. Previous studies have focused mainly on the immunoglobulin G (IgG) isotype owing to the analytical challenges associated with other isotypes. Thus, the development of a sensitive and accurate analytical platform is necessary to characterize antibody glycosylation across multiple isotypes. In this study, we have developed an analytical workflow using antibody-light-chain affinity beads to purify IgG, IgA, and IgM from 16 µL of human plasma. Dual enzymes, trypsin and Glu-C, were used during on-bead digestion to obtain enzymatic glycopeptides and protein-specific surrogate peptides. Ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry was used in order to determine the sensitivity and specificity. Our platform targets 95 glycopeptides across the IgG, IgA, and IgM isotypes, as well as eight surrogate peptides representing total IgG, four IgG classes, two IgA classes, and IgM. Four stable isotope-labeled internal standards were added after antibody purification to calibrate the preparation and instrumental bias during analysis. Calibration curves constructed using serially diluted plasma samples showed good curve fitting (R2 > 0.959). The intrabatch and interbatch precision for all the targets had relative standard deviation of less than 29.6%. This method was applied to 19 human plasma samples, and the glycosylation percentages were calculated, which were comparable to those reported in the literature. The developed method is sensitive and accurate for Ig glycosylation profiling. It can be used in clinical investigations, particularly for detailed humoral immune profiling.

Development of a social cognitive career theory scale for measuring the intention to select surgery as a career.

Background: Surgeon shortages have emerged as a prominent global issue. Although various studies have explored the factors that influence medical students in choosing surgery as a career, addressing the need for surgeons requires a multifaceted approach. However, there is currently a lack of a theoretically grounded scale to evaluate the effectiveness of surgical career development or policy promotion. Thus, this study aimed to develop a questionnaire for assessing the preference for a surgical career by adopting the Social Cognitive Career Theory (SCCT). Materials and methods: The study aimed to develop the Social Cognitive Career Theory Scale toward Surgery (SCCTSS) by adopting the framework of SCCT. The questionnaire was created through expert consensus and the content validity index (CVI) calculation. Subsequently, a pilot version of the SCCTSS was administered to 222 medical students in their clinical clerkships, and the collected data underwent item analysis. Additionally, the validation of the SCCTSS by gender was performed. Results: The SCCTSS comprised 16 items that passed expert panel evaluation, with a CVI >0.8, mean ≥ 3.00, and an interquartile range ≤1. Item analysis demonstrated that the quality of the SCCTSS met the qualifying threshold. Furthermore, the SCCTSS questionnaire effectively validated gender differences in surgical career preference. Conclusions: We developed an internally consistent and reliable scale and validated it through an expert panel method and feedback from medical students. Further research is required to evaluate the targeted interventions that may assist in recruiting medical students into the field of surgery through the application of the SCCTSS.

Efficacy and safety of sodium-glucose cotransporter-2 inhibitors in patients with chronic kidney disease: a systematic review and meta-analysis.

PURPOSE: Owing to the pharmacological mechanism, sodium-glucose cotransporter 2 inhibitors (SGLT2is) may be less effective in patients with reduced renal functions, but no systematic review or meta-analysis addressed chronic kidney disease (CKD) patients specifically. We aimed to assess the efficacy and safety of SGLT2is in CKD patients. METHODS: We conducted a systematic review and meta-analysis of randomized controlled trials. Mean difference (MD) were pooled for the decline of glomerular filtration rate (eGFR) and change in urine albumin-to-creatinine ratio (uACR). Hazard ratio (HR) and rate ratio (RR) were pooled for composite of renal outcomes and adverse effects. RESULTS: Thirty articles were identified. Overall MD in rate of eGFR decline was 0.02 (P = 0.05), with a borderline significant difference favoring SGLT2is, while the change in uACR from baseline was - 141.34 mg/g and hazard ratio of composite renal outcomes was 0.64 significantly favoring SGLT2is. Subgroup analyses showed that the long-term renal function, participants with baseline macroalbuminuria, and stage 4 CKD patients had significantly slower eGFR decline rate in SGLT2is compared to the placebo group. Risks of genital mycotic infection and ketoacidosis were significantly higher among the SGLT2is group than placebo. CONCLUSION: For CKD patients, no matter diabetic or non-diabetic, our study showed potential renoprotective effects favoring SGLT2is in overall and long-term phase, and in patients with macroalbuminuria or stage 4 CKD. However, only slight increased risk of adverse effects among the SGLT2is group is observed. Therefore, we concluded that in CKD patients, prescribing SGLT2is was safe and had renal benefits.

Comparison of Humoral Antibody Responses and Seroconversion Rates between Two Homologous ChAdOx1 nCoV-19 and mRNA-1273 Vaccination in Patients Undergoing Maintenance Hemodialysis.

BACKGROUND: Hemodialysis patients are at an increased risk of SARS-CoV-2 infection and are excluded from preauthorization COVID-19 vaccine trials; therefore, their immunogenicity is uncertain. METHODS: To compare the antibody responses to homologous ChAdOx1 and mRNA-1273 SARS-CoV-2 vaccination in hemodialysis patients, 103 age- and sex-matched hemodialysis patients with two homologous prime-boost vaccinations were recruited to detect anti-receptor-binding domain (RBD) IgG levels and seroconversion rates (SCRs) 14 days after a prime dose (PD14), before and 28 days after a boost dose (pre-BD0 and BD28). RESULTS: Both mRNA-1273 and ChAdOx1 vaccinations elicited immunogenicity in study subjects, and the former induced higher anti-RBD IgG levels than the latter. The SCRs of both groups increased over time and varied widely from 1.82% to 97.92%, and were significantly different at PD14 and pre-BD0 regardless of different thresholds. At BD28, the SCRs of the ChAdOx1 group and the mRNA-1273 group were comparable using a threshold ≥ 7.1 BAU/mL (93.96% vs. 97.92%) and a threshold ≥ 17 BAU/mL (92.73% vs. 97.92%), respectively, but they were significantly different using a threshold ≥ 20.2% of convalescent serum anti-RBD levels (52.73% vs. 95.83%). The seroconversion (≥20.2% of convalescent level) at BD28 was associated with mRNA-1273 vaccination after being adjusted for age, sex, body mass index, and the presence of solicited reactogenicity after a prime vaccination. CONCLUSION: Our prospective, observational cohort indicates that a full prime-boost mRNA-1273 vaccination is likely to provide higher immune protection in hemodialysis patients compared to ChAdOx1, and this population with a prime-boost ChAdOx1 vaccination should be prioritized for a third dose.

Effects of osteoporosis medications on bone fracture in patients with chronic kidney disease.

PURPOSE OF THE STUDY: The risk of bone fracture is high in patients with chronic kidney disease (CKD), and aggressive treatment to reduce fragility fracture risk is the major strategy. However, the outcomes of osteoporosis medications in patients with CKD remain unclear. STUDY DESIGN: Patients with stage 3-5 CKD during 2011-2019 were enrolled. Patients were divided into two groups based on receiving osteoporosis medications (bisphosphonates, raloxifene, teriparatide or denosumab) or not. Two groups were matched at a 1:1 ratio by using propensity scores. The outcomes of interest were bone fractures, cardiovascular (CV) events and all-cause mortality. Cox proportional hazard regression models were applied to identify the risk factors. Additional stratified analyses by cumulative dose, treatment length and menopause condition were performed. RESULTS AND CONCLUSIONS: 67 650 patients were included. After propensity score matching, 1654 patients were included in the study and control group, respectively. The mean age was 70.2±12.4 years, and 32.0% of patients were men. After a mean follow-up of 3.9 years, the incidence rates of bone fracture, CV events and all-cause mortality were 2.0, 1.7 and 6.5 per 1000 person-months, respectively. Multivariate analysis results showed that osteoporosis medications reduced the risk of CV events (HR, 0.35; 95% CI, 0.18 to 0.71; p = 0.004), but did not alleviate the risks of bone fracture (HR, 1.48; 95% CI, 0.73 to 2.98; p = 0.28) and all-cause mortality (HR, 0.93; 95% CI, 0.67 to 1.28; p = 0.65). Stratified analysis showed that bisphosphonates users have most benefits in the reduction of CV events (HR, 0.26; 95% CI, 0.11 to 0.64; p = 0.003). In conclusion, osteoporosis medications did not reduce the risk of bone fractures, or mortality, but improved CV outcomes in patients with CKD.

Development of an enrichment-free one-pot sample preparation and ultra-high performance liquid chromatography-tandem mass spectrometry method to identify Immunoglobulin A1 hinge region O-glycoforms for Immunoglobulin A nephropathy.

Immunoglobulin A nephropathy (IgAN) is a highly prevalent autoimmune renal disease. Human IgA1 with galactose deficiency in the hinge region (HR) has been identified as an autoantigen for this disease. Therefore, analyzing IgA1 HR glycoforms in biofluids is important for biomarker discovery. Herein, an analytical method that includes one-pot sample preparation with unbiased plasma IgA purification, dual internal standard addition, and sensitive ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectroscopy (UHPLC-QqQ-MS/MS) was developed. Targeted O-glycopeptides detection was performed in pooled plasma with the validation of theoretical retention times, enzymatic treatment outcomes, product ion scans, and signal repeatability. A total of 42 IgA1 O-glycopeptides with N-acetylgalactosamines, galactoses, and sialic acids were determined from 8 µL of plasma. The newly developed method was applied to plasma samples from 16 non-IgAN controls and 19 IgAN patients. Comparing the 42 targets, 16 IgA1 HR O-glycopeptides were statistically different between the two groups (p<0.05). Decreased sialylation was identified in the IgA1 hinge region of IgAN patients, which was also correlated with the estimated glomerular filtration rate (eGFR). The developed method is sensitive and precise and can be used to identify plasma biomarkers for IgA nephropathy.

Genome-Wide Association Study for eGFR in a Taiwanese Population.

BACKGROUND AND OBJECTIVES: Chronic kidney disease (CKD) is a global public health issue associated with large economic burdens. CKD contributes to higher risks of cardiovascular complications, kidney failure, and mortality. The incidence and prevalence rates of kidney failure in Taiwan have remained the highest in the world. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Assessing genetic factors that influence kidney function in specific populations has substantial clinical relevance. We investigated associations of genetic variants with eGFR. The quality control filtering and genotype imputation resulted in 10,008 Taiwan Biobank participants and 6,553,511 variants for final analyses. We examined these loci with in silico replication in individuals of European and African ancestry. RESULTS: Our results revealed one significant locus (4q21.1) and three suggestive significant loci (17q23.2, 22q13.2, and 3q29) for eGFR in the Taiwanese population. In total, four conditional-independent single nucleotide polymorphisms were identified as the most important variants within these regions, including rs55948430 (Coiled-Coil Domain Containing 158), rs1010269 (BCAS3), rs56108505 (MKL1), and rs34796810 (upstream of DLG1). By performing a meta-analysis, we found that the 4q21.1 and 17q23.2 loci were successfully replicated in the European population, whereas only the 17q23.2 locus was replicated in African ancestry. Therefore, these two loci are suggested to be transethnic loci, and the other two eGFR-associated loci (22q13.2 and 3q29) are likely population specific. CONCLUSIONS: We identified four susceptibility loci on 4q21.1, 17q23.2, 22q13.2, and 3q29 that associated with kidney-related traits in a Taiwanese population. The 22q13.2 (MKL1) and 3q29 (DLG1) were prioritized as critical candidates. Functional analyses delineated novel pathways related to kidney physiology in Taiwanese and East Asian ancestries.

Effect of Dialysis Modalities on All-Cause Mortality and Cardiovascular Mortality in End-Stage Kidney Disease: A Taiwan Renal Registry Data System (TWRDS) 2005-2012 Study.

Introduction: End-stage kidney disease (ESKD) patients who need renal replacement therapy need to face a dialysis modality decision: the choice between hemodialysis (HD) and peritoneal dialysis (PD). Although the global differences in HD/PD penetration are affected by health-care policies, these two modalities may exert different effects on survival in patients with ESKD. Although Taiwan did not implicate PD as first policy, we still need to compare patients' outcomes using two modalities in a nation-wise database to determine future patients' care and health policies. Methods: We used the nationwide Taiwan Renal Registry Data System (TWRDS) database from 2005 to 2012 and included 52,900 patients (48,371 on HD and 4529 on PD) to determine all-cause and cardiovascular mortality among ESKD patients. Results: Age-matched survival probability from all-cause mortality was significantly lower in patients on PD than in those on HD (p < 0.05). The adjusted hazard ratios of 3-year and 5-year all-cause and cardiovascular mortality were significantly higher in PD compared with HD. The presence of comorbid conditions including myocardial infarction, coronary artery disease (CAD), diabetes mellitus (DM), hypoalbuminemia, hyperferritinemia and hypophosphatemia was related with significantly higher all-cause and CV mortality in PD patients. No significant difference was noted among younger patients <45 years of age regardless of DM and/or comorbid conditions. Conclusion: Although PD did not have the survival advantage compared to HD in all dialysis populations, PD was related with superior survival in younger non-DM patients, regardless of the presence of comorbidities. Similarly, for younger ESKD patients without the risk of CV disease, both PD and HD would be suitable dialysis modalities.

The Effect of Statin on Anemia in Patients with Chronic Kidney Disease and End-Stage Kidney Disease: A Systematic Review and Meta-Analysis.

Although erythropoietin-stimulating agents are effective in treating anemia in patients with end-stage kidney disease (ESKD) undergoing hemodialysis, some ESKD patients, especially those with inflammation, continue to suffer from anemia. Statin, an inhibitor of hydroxymethylglutaryl-CoA (HMG-CoA) reductase with lipid-lowering effects, may have a pleiotropic effect in reducing inflammation, and thus increase hemoglobin (Hb) level. We searched the PubMed, Embase, and Cochrane databases for relevant studies. The population of interest comprised advanced chronic kidney disease (CKD) patients and ESKD patients receiving hemodialysis with statin treatment. The included study designs were randomized control trial/cohort study/pre-post observational study, and outcomes of interest were Hb, erythropoietin resistance index (ERI) and ferritin. PRISMA 2020 guidelines were followed, and risk of bias (RoB) was assessed using the RoB 2.0 tool in randomized controlled trials, and the Newcastle-Ottawa scale (NOS) in cohort studies. We eventually included ten studies (5258 participants), comprising three randomized controlled trials and seven cohort studies. Overall, Hb increased by 0.84 g/dL (95% confidence interval [CI]: -0.02 to 1.70) in all groups using statins, including single-arm cohorts, and by 0.72 g/dL (95% CI: -0.02 to 1.46) in studies with placebo control. Hb levels were higher in the study group than in the control group, with a mean difference of 0.18 g/dL (95% CI: 0.04-0.32) at baseline and 1.0 g/dL (95% CI: 0.13-1.87) at the endpoint. Ferritin increased by 9.97 ng/mL (95% CI: -5.36 to 25.29) in the study group and decreased by 34.01 ng/mL (95% CI: -148.16 to 80.14) in the control group; ferritin fluctuation was higher in the control group. In conclusion, statin may improve renal anemia in ESKD patients receiving hemodialysis and regular erythropoietin-stimulating agents. Future studies with more rigorous methodology and larger sample size study should be performed to confirm this beneficial effect.

Association Between DPP-4 Inhibitors and Events of Colorectal and Liver Cancers in Patients With Diabetes Receiving Second-Line Agents: A Nested Case-Control Study.

Objective: Plasma dipeptidyl peptidase-4 (DPP4) levels were significantly lower in patients with colorectal and liver cancers, and animal studies also showed DPP4 inhibitors (DPP4is) have procarcinogenic effects in colorectal cancer. Until now, whether DPP4is therapy affects the progression of liver cancer and colorectal cancer in patients with T2DM has not been well investigated. We investigated the association between cumulative defined daily dose (cDDD) of DPP4is exposure and risks of liver and colorectal cancers in patients with type 2 diabetes. Materials and Methods: We identified 268,520 patients with diabetes receiving DPP4is as second-line agents between March 1, 2009, and December 31, 2013, from Taiwan's National Health Insurance Research Database, Taiwan Cancer Registry, and National Death Registry of Taiwan. The amount of DPP4is were divided into three groups (low, medium, and high) based on the interquartile range of the cDDD of the DPP4is. Results: The data showed that the low cDDD of DPP-4is was associated with a reducing risk of colorectal cancer [adjusted odds ratio (OR), 0.49; 95% CI, 0.32-0.75; P=0.001]. However, the high cDDD of DPP-4is was associated with an increasing risk of colorectal cancer (adjusted OR, 1.86; 95% CI, 1.32-2.61; P<0.001). No association between DPP4is use and liver cancer risk was observed. Conclusions: This nested case study revealed a J-shaped association between the cDDD of DPP-4is and colorectal cancer risk, but not liver cancer risk. Therefore, the effects of long-term DPP4is use on colorectal cancer risk warrant further study.

A Consistency Model for Identifying the Effects of n-3 and n-6 Fatty Acids on Lipoproteins in Dialysis Patients.

Numerous randomized controlled trials (RCTs) and meta-analyses have assessed the effects of supplemental dietary polyunsaturated fatty acids (PUFAs) on levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) and the LDL/HDL ratio in patients receiving renal replacement therapy (RRT). However, results are ambiguous due to mixed reports of various nutrients used in the intervention group. We performed a network meta-analysis of RCTs to assess the effects of PUFAs on lipid profiles in patients undergoing RRT. RCTs performed before November 2021 were gathered from three databases. The means, standard deviations and the number of cases for each arm were independently extracted by two authors to form a network meta-analysis of LDL and HDL levels and the LDL/HDL ratio in a random effects model. Twenty-eight RCTs (n = 2017 subjects) were included in this study. The pooled results revealed that the combination of omega-3 fatty acids (n-3) and omega-6 fatty acids (n-6) produced significantly lower LDL (standardized mean difference (SMD) = -1.43, 95% confidence interval: -2.28 to -0.57) than the placebo. Both n-3 fatty acids (SMD = 0.78) and the combination of n-3 + n-6 (SMD = 1.09) benefited HDL significantly compared with placebo. Moreover, n-3 alone also exhibited a significantly lower LDL/HDL ratio than placebo. Collectively, PUFAs seem to be adequate nutrients for controlling lipoproteins in patients undergoing RRT. Specifically, n-3 + n-6 supplementation improved LDL levels, while n-3 improved HDL levels and the LDL/HDL ratio. However, our data provide limited information on specific dosages of PUFAs to form a concrete recommendation.

Effects of Periodontal Treatment in Patients with Periodontitis and Kidney Failure: A Pilot Study.

Periodontitis and chronic kidney disease are both chronic inflammatory diseases and share some common risk factors. This 3-month pilot study aimed to clarify whether non-surgical periodontal therapy is beneficial in clinical, biochemical, and microbiological conditions in patients with periodontitis and kidney failure. Kidney failure patients with moderate to severe periodontitis were recruited from two hospitals. Treatment group received non-surgical periodontal therapy, and control group received oral hygiene instruction only. Outcome assessments were conducted 1 and 3 months after treatment. Non-parametric tests were used to analyze the patient-level data. Periodontal site-level assessments were analyzed by Student t-test and paired t-test. Statistical significance was set at p-value < 0.05. A total of 11 subjects completed the study. There was no significant difference between groups in all-cause mortality, cardiovascular events, infection events, systemic parameters, and serum biomarkers. Comparing to control group, clinical periodontal parameters, gingival crevicular fluid interleukin-1ß (IL-1ß) level and periodontal pathogens showed significant improvement in the treatment group. Non-surgical periodontal treatment did not change systemic outcomes in kidney failure patients, but changed the local micro-environment.

The Humoral Immune Response of the ChAdOx1 nCoV-19 Vaccine in Maintenance Dialysis Patients without Prior COVID-19 Infection.

BACKGROUND: Chronic kidney disease (CKD) patients tend to have a reduced immune response to infection and vaccination. The efficacy of current available COVID-19 vaccines in CKD patients has not been widely evaluated. METHODS: In the present study, three hundred and eight chronic dialysis patients received ChAdOx1 nCoV-19 (Oxford-AstraZeneca, AZ). Blood tests using an antibody against the receptor-binding domain (RBD) of the S1 subunit of the SARS-CoV-2 spike protein had performed at four designed time points before and after the first and second vaccine. RESULTS: The mean age of patients was 65.5 ± 12.38 years, and the male/female ratio was 61.4%:38.6% (189/119). Two weeks after the first vaccination, only 37.66% of patients had a positive antibody response (>50 AU/mL). However, 65.58% of the participants showed a delayed antibody response ten weeks after the first vaccine. Four weeks after the second vaccine, 94.16% of participants had positive antibody levels. Age was the most significant factor associated with antibody response. Flow cytometry analysis revealed that immune-naïve patients had significantly lower early active B cells and proliferative B cells than the age- and sex-matched immune responders. CONCLUSION: Despite a delayed response, 94.16% of chronic dialysis patients achieved a positive antibody response after two doses of the AZ vaccine. Age is the most significant factor associated with antibody response.

Oral microbiota in xerostomia patients - A preliminary study.

BACKGROUND/PURPOSE: The estimated prevalence of xerostomia (lack of saliva) ranges from 10% to 50% of the general population. The oral cavity provides a multivariant environmental habitat to over 700 species of bacteria and fungi. We hypothesized that xerostomia will alter the composition of oral microbiota. MATERIAL AND METHODS: Nineteen xerostomia patients and 10 healthy normal volunteers were studied for the oral microbiota. Gingival plaques were collected and microbiota were detected using bacterial 16S ribosomal RNA and analyzed based on the levels of phylum and class. RESULTS: In all cases, phyla of Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Proteobacteria make up to 100% of oral microbiota at phylum level. Analyzing individual phylum, presence of Bacteroidetes in xerostomia patients and normal subjects were 23.12 ± 2.56% and 23.23 ± 2.58%, respectively. Mean percentage presence of Firmicutes phylum in xerostomia patients and normal subjects were 18.94 ± 1.83% and 14.06 ± 0.98%, respectively. Statistically significant difference was not observed between xerostomia patients and normal subjects in this study. CONCLUSION: These observations revealed obvious but not statistically significant changes in oral major microorganism phylum between xerostomia patients and normal subjects in this study. More samples are needed to verify the current results and to use oral microbiota as a tool in the diagnosis of xerostomia.

Effects of osteoporosis medications on bone fracture in patients with chronic kidney disease.

PURPOSE OF THE STUDY: The risk of bone fracture is high in patients with chronic kidney disease (CKD), and aggressive treatment to reduce fragility fracture risk is the major strategy. However, the outcomes of osteoporosis medications in patients with CKD remain unclear. STUDY DESIGN: Patients with stage 3-5 CKD during 2011-2019 were enrolled. Patients were divided into two groups based on receiving osteoporosis medications (bisphosphonates, raloxifene, teriparatide or denosumab) or not. Two groups were matched at a 1:1 ratio by using propensity scores. The outcomes of interest were bone fractures, cardiovascular (CV) events and all-cause mortality. Cox proportional hazard regression models were applied to identify the risk factors. Additional stratified analyses by cumulative dose, treatment length and menopause condition were performed. RESULTS AND CONCLUSIONS: 67 650 patients were included. After propensity score matching, 1654 patients were included in the study and control group, respectively. The mean age was 70.2±12.4 years, and 32.0% of patients were men. After a mean follow-up of 3.9 years, the incidence rates of bone fracture, CV events and all-cause mortality were 2.0, 1.7 and 6.5 per 1000 person-months, respectively. Multivariate analysis results showed that osteoporosis medications reduced the risk of CV events (HR, 0.35; 95% CI, 0.18 to 0.71; p = 0.004), but did not alleviate the risks of bone fracture (HR, 1.48; 95% CI, 0.73 to 2.98; p = 0.28) and all-cause mortality (HR, 0.93; 95% CI, 0.67 to 1.28; p = 0.65). Stratified analysis showed that bisphosphonates users have most benefits in the reduction of CV events (HR, 0.26; 95% CI, 0.11 to 0.64; p = 0.003). In conclusion, osteoporosis medications did not reduce the risk of bone fractures, or mortality, but improved CV outcomes in patients with CKD.

Effect of dialyzer membranes on mortality in uremic patients undergoing long-term hemodialysis: A Nationwide population-based study using the Taiwan Dialysis Registry Data System 2005-2012.

The characteristics in dialyzer are associated with mortality in patients with end-stage renal disease (ESRD) receiving hemodialysis (HD). This study is to investigate the effects of dialyzer membranes on 3-year mortality in ESRD patients. From the long-term nationwide population database. Prevalent HD patients during 2005-2012 were enrolled. Our main analysis to calculate the effect was cox regression multivariate model. Overall, the mean age of all population (N = 73 565) was 61.0 ± 13.6 years, the observation period is 2.46 years ±0.98 within 3 years and 64.6% used polysulfone (PS), polymethyl methacrylate (PMMA) (11.6%), polyethersulfone (11.4%), and cellulose triacetate (CTA) (10.7%), ethylene vinyl alcohol (EVAL) (hazard ratio [HR] 2.72, 95% confidence interval [CI] 1.71-4.33) and CTA (HR 1.35, 95% CI 1.12-1.64) were associated with higher mortality than PS, but PMMA was not. EVAL and CTA adversely affected mortality and PMMA had no protective role. Further investigations on membrane characters on HD patients are warranted. Taipei Medical University (TMU) (TMU-JIRB (No. N201804051).

Affinity Purification Coupled to Stable Isotope Dilution LC-MS/MS Analysis to Discover IgG4 Glycosylation Profiles for Autoimmune Pancreatitis.

Type 1 autoimmune pancreatitis (AIP) is categorized as an IgG4-related disease (IgG4-RD), where a high concentration of plasma IgG4 is one of the common biomarkers among patients. IgG Fc-glycosylation has been reported to be potential biosignatures for diseases. However, human IgG3 and IgG4 Fc-glycopeptides from populations in Asia were found to be isobaric ions when using LC-MS/MS as an analytical tool. In this study, an analytical workflow that coupled affinity purification and stable isotope dilution LC-MS/MS was developed to dissect IgG4 glycosylation profiles for autoimmune pancreatitis. Comparing the IgG4 and glycosylation profiles among healthy controls, patients with pancreatic ductal adenocarcinoma (PDAC), and AIP, the IgG4 glycosylations from the AIP group were found to have more digalactosylation (compared to PDAC) and less monogalactosylation (compared to HC). In addition, higher fucosylation and sialylation profiles were also discovered for the AIP group. The workflow is efficient and selective for IgG4 glycopeptides, and can be used for clinical biosignature discovery.