Characteristics of T cell premature senescence in maintenance hemodialysis patients.

BACKGROUND: Uremia-associated immunodeficiency, mainly characterized by T cell dysfunction, exists in patients on maintenance hemodialysis (MHD) and promotes systemic inflammation. However, T cell senescence, one of the causes of T cell dysfunction, has not been clearly revealed yet. In this cross-sectional research, we aimed to study the manifestation of T cell premature senescence in MHD patients and further investigate the associated clinical factors. METHODS: 76 MHD patients including 33 patients with cardiovascular diseases (CVD) and 28 patients with arteriovenous fistula (AVF) event history were enrolled in this study. Complementarity determining region 3 (CDR3) of T cell receptor (TCR) was analyzed by immune repertoire sequencing (IR-Seq). CD28- T cell subsets and expression of senescence marker p16 and p21 genes were detected by multicolor flow cytometry and RT-qPCR, respectively. RESULTS: MHD patients had significantly decreased TCR diversity (P < 0.001), increased CDR3 clone proliferation (P = 0.001) and a left-skewed CDR3 length distribution. The proportion of CD4 + CD28- T cells increased in MHD patients (P = 0.014) and showed a negative correlation with TCR diversity (P = 0.001). p16 but not p21 expression in T cells was up-regulated in MHD patients (P = 0.039). Patients with CVD exhibited increased expression of p16 and p21 genes (P = 0.010 and 0.004, respectively), and patients with AVF events showed further TCR diversity and evenness reduction (P = 0.002 and 0.017, respectively) compared to patients without the comorbidities. Moreover, age, average convection volume, total cholesterol, high-density lipoprotein cholesterol and transferrin saturation were associated with TCR diversity or CD4 + CD28- T cell proportion (P < 0.05). CONCLUSIONS: MHD patients undergo T cell premature senescence characterized by significant TCR diversity reduction and repertoire skew, as well as accumulation of the CD4 + CD28- subset and up-regulation of p16 gene. Patients with CVD or AVF events show higher level of immunosenescence. Furthermore, T cell senescence in MHD patients is associated with blood cholesterol and uremic toxin retention, suggesting potential intervention strategies in the future.

Aeromonas spp. from hospital sewage act as a reservoir of genes resistant to last-line antibiotics.

BACKGROUND: Aeromonas species are opportunistic pathogens distributed widely in the ecosystem. They are known to be capable of acquiring antibiotic resistance genes, including those encoding proteins against last-line antibiotics, such as the tmexCD-toprJ, mcr and carbapenemase genes. We investigated the genomic and phenotypic characteristics of tmexCD-toprJ-positive Aeromonas strains collected from human, animals, and water samples, particularly those from hospital wastewater in China. METHODS: Samples were collected from living animals, meat, water and human. Aeromonas strains in these samples were isolated in selective media. Antimicrobial resistance profiles of all Aeromonas strains were tested by the broth microdilution method. The presence of tmexCD-toprJ was verified by polymerase chain reaction (PCR). All tmexCD-toprJ-positive (n = 36) and selected tmexCD-toprJ-negative (n = 18) Aeromonas strains were subjected to whole genome sequencing. Carriage of antimicrobial resistance genes, the genetic environment of tmexCD-toprJ and genetic diversity of tmexCD-toprJ-positive Aeromonas strains were determined by bioinformatics analysis. Phylogenetic tree of the Aeromonas strains was built by using the Harvest Suite. FINDINGS: Among the 636 Aeromonas strains isolated from different sources, 36 were positive for tmexCD-toprJ, with the highest prevalence of tmexCD-toprJ being found in fishes (8.8%, 95 CI% 3.6-17.2%), followed by hospital wastewater (6.5%, 95 CI% 4.3-9.3%), river water (2.0%, 0.1-10.9) and duck (1.2%, 95 CI% 3.6-17.2%). All tmexCD-toprJ-positive Aeromonas strains carried multiple antimicrobial resistance genes and exhibited resistance to different classes of antibiotics. Co-existence of tmexCD-toprJ, mcr and blaKPC-2 were identified in 21 strains. The tmexCD-toprJ-positive Aeromonas strains were genetically diverse and found to belong to four different species that could be clustered into three major lineages. The tmexCD-toprJ gene clusters were predominantly located in the chromosome (35/36) of Aeromonas spp., with only one strain carrying the plasmid-borne tmexCD-toprJ cluster. The tmexCD-toprJ genes were associated with seven different types of genetic environments, each of which carried distinct types of mobile elements that may be responsible for mediating transmission of this gene cluster.

Genome-Wide Identification and Expression Analysis of GATA Family Genes in Dimocarpus longan Lour.

GATA transcription factors, which are DNA-binding proteins with type IV zinc finger binding domains, have a role in transcriptional regulation in biological organisms. They have an indispensable role in the growth and development of plants, as well as in improvements in their ability to face various environmental stresses. To date, GATAs have been identified in many gene families, but the GATA gene in longan (Dimocarpus longan Lour) has not been studied in previous explorations. Various aspects of genes in the longan GATA family, including their identification and classification, the distribution of their positions on chromosomes, their exon/intron structures, a synteny analysis, their expression at different temperatures, concentration of PEG, early developmental stages of somatic embryos and their expression levels in different tissues, and concentrations of exogenous hormones, were investigated in this study. This study showed that the 22 DlGATAs could be divided into four subfamilies. There were 10 pairs of homologous GATA genes in the synteny analysis of DlGATA and AtGATA. Four segmental replication motifs and one pair of tandem duplication events were present among the DlGATA family members. The cis-acting elements located in promoter regions were also found to be enriched with light-responsive elements, which contained related hormone-responsive elements. In somatic embryos, DlGATA4 is upregulated for expression at the globular embryo (GE) stage. We also found that DlGATA expression was strongly up-regulated in roots and stems. The study demonstrated the expression of DlGATA under hormone (ABA and IAA) treatments in embryogenic callus of longan. Under ABA treatment, DlGATA4 was up-regulated and the other DlGATA genes did not respond significantly. Moreover, as demonstrated with qRT-PCR, the expression of DlGATA genes showed strong up-regulated expression levels under 100 µmol·L-1 concentration IAA treatment. This experiment further studied these and simulated their possible connections with a drought response mechanism, while correlating them with their expression under PEG treatment. Overall, this experiment explored the GATA genes and dug into their evolution, structure, function, and expression profile, thus providing more information for a more in-depth study of the characteristics of the GATA family of genes.

Adaptive immune dysfunction in patients with COVID-19 and impaired kidney function during the omicron surge.

BACKGROUND: Little is known about the characteristics of lymphocyte subsets and the association with patient outcomes in COVID-19 with and without impaired kidney function. METHODS: Lymphocyte subsets were compared in COVID-19 patients with or without kidney dysfunction. The primary outcome was a composite of all-cause mortality or intensive care unit admission. Secondary outcomes included duration of viral shedding, length of hospital stay, and acute kidney injury. RESULTS: Lymphocyte subset cell counts demonstrated the lowest in patients with severe/critical COVID-19 and kidney dysfunction. Among all lymphocyte subset parameters, Th cell count was the most significant indicator for outcomes. ROC of the combined model of Th cell count and eGFR presented better predictive value than that of the other parameters. Th cell count <394.5 cells/µl and eGFR <87.5 ml/min/1·73m2 were independently associated with poor outcomes. The propensity score matching analysis revealed consistent results. CONCLUSIONS: Reduced Th cell count and eGFR may be applied as promising predictive indicators for identifying COVID-19 patients with high risk and poor outcomes.

Co-transfer of last-line antibiotic resistance and virulence operons by an IncFIBk-FII-X3-ColKP3 hybrid plasmid in Klebsiella pneumoniae.

OBJECTIVES: To characterize a clinical Klebsiella pneumoniae isolate from China co-harbouring tet(X4), blaOXA-181 and the aerobactin operon on an IncFIBk-FII-X3-ColKP3 hybrid plasmid. METHODS: A tigecycline-resistant strain was recovered from the intestinal sample of a patient. It was subjected to antimicrobial susceptibility testing, conjugation assay, virulence testing, WGS, bioinformatics analysis, plasmid stability testing and fitness cost testing. RESULTS: The strain K. pneumoniae T877 was resistant to tigecycline, intermediate to piperacillin/tazobactam and ertapenem, and positive for tet(X), blaOXA-181 and the virulence-associated operon iutAiucABCD, which were located on the same plasmid, named pKPT877-hybrid. It was 99.96% identical to the IncFIBk-FII plasmid pSCH6109-Vir (accession number CP050860) from K. pneumoniae strain SCH6109 at 96% coverage with the absence of a 50 kb region on pKPT877-hybrid; this region was highly homologous to the 51 kb IncX3-ColKP3-type, blaOXA-181-carrying plasmid pOXA181-191773 (accession number CP080367). Plasmid pKPT877-hybrid was conjugatively transferable to the ST11 K. pneumoniae strains FJ8 and KP04. pKPT877-hybrid did not have a significant impact on the fitness cost and could be maintained stably in T877. CONCLUSIONS: We report for the first time (to the best of our knowledge) the co-transfer of last-line antibiotic resistance determinants [tet(X4) and blaOXA-181] and the aerobactin operon (iutAiucABCD) by a mobile IncFIBk-FII-X3-ColKP3 hybrid plasmid, which can be stably maintained in K. pneumoniae strains, even in the absence of antibiotic selective pressure. Once the plasmid transfers to a K. pneumoniae with porin deficiency, the strain might have high levels of resistance to carbapenems and tigecycline, which are the last line of defence against infections. Heightened and continuous efforts are needed to control its dissemination.

Cavitation assisted endoplasmic reticulum targeted sonodynamic droplets to enhanced anti-PD-L1 immunotherapy in pancreatic cancer.

BACKGROUND: Sonodynamic therapy (SDT) induces immunogenic cell death (ICD) in tumors and promises to play an assistive role in immunotherapy in pancreatic cancer. However, the short half-life and limited diffusion distance of reactive oxygen species (ROS) impair ICD induction, especially in tumors with relatively poor blood perfusion and dense stroma. RESULTS: To address this problem, we fabricated cavitation-assisted endoplasmic reticulum (ER) targeted sonodynamic nanodroplets (PMPS NDs, 329 nm). The good sonodynamic effect and precise endoplasmic reticulum target effect was verified. After intravenous injection, the cRGD peptide modified nanodroplets initially aggregated around the tumor vascular endothelial cells. Stimulated by ultrasound, the liquid-to-gas bubbles began to oscillate and cavitate. This acoustic droplet evaporation strategy facilitated transport of the nanoparticle across the vessel, with deep penetration. This loosened the tumor stroma and facilitated accumulation and penetration of loaded sonosensitizer after 6 h. The modified sonosensitizer can selectively accumulate in the ER to generate a large amount of ROS in situ, inducing potent ER stress, amplified ICD and dendritic cell maturation in vitro and in vivo. Furthermore, the elevated antitumor effect of SDT plus anti-PD-L1 immunotherapy was verified using an orthotopic tumor model. CONCLUSIONS: This study reports a cavitation assisted ER targeted sonodynamic therapy that can enhance the effect of anti-PD-L1 immunotherapy effectively in orthotopic and distant pancreatic cancer.

Effectiveness of a double-carbapenem combinations against carbapenem-resistant Gram-negative bacteria.

The emergence of carbapenem-resistant organisms posed considerable threat to global health while only limited treatment options are available and led to efforts to discover a novel way to treat them. To evaluate in vitro synergistic activity of meropenem plus ertapenem, a total of 203 carbapenem-resistant strains, collected from 12 provinces and municipalities in China, were examined with a dual carbapenem combination therapy. The statistical software R was used for analysis. Two hundred and one (201) of carbapenem-resistant strains mainly produced four types of carbapenemase: KPC-2 (n = 142, 69.95%), OXA-232 (n = 7, 3.45%), NDM (n = 38, 18.72%; 36 NDM-1, 1 NDM-4, 1 NDM-5), and IMP (n = 15, 7.39%; 1 IMP-26, 10 IMP-30, 4 IMP-4). Fifty-one out of two hundred and three (51/203 or 25.12%) of the examined strains showed a synergistic effect for the meropenem plus ertapenem combination throughout the checkerboard method, while only three isolates showed potential clinically relevant synergy (3/203, 1.48%). An additive effect was observed in 55/203 (27.09%) of the examined strains. Ninety-seven of the examined isolates (47.78%) showed fractional inhibitory concentration (FIC) greater or equal to 2 (indicating antagonism). The synergistic activity of meropenem plus ertapenem combination suggests this combination can be a possible way to treat the infection caused by the carbapenem-resistant organisms, especially for IMP or NDM producer with a lesser minimum inhibitory concentration (MIC) and the infected individual who was not recommended to use colistin or tigecycline.

Chromosomal and Plasmid-Borne Tigecycline Resistance Genes tet(X3) and tet(X4) in Dairy Cows on a Chinese Farm.

We isolated 47 Acinetobacter strains carrying tet(X3) and 4 ST767 E. coli strains carrying tet(X4) from 296 rectal swab samples from dairy cows on a Chinese farm. tet(X3) was located on chromosomes or diverse plasmids, and tet(X4) was located on IncFIBκ/FIA(HI1)/X1 nontransferable plasmid. The coexistence of tet(X3) and carbapenemase genes, including blaOXA-58 and blaNDM-1, was detected in 9 Acinetobacter spp. These findings suggested that the use of tetracycline and other antibiotics in food production warrants urgent attention.

Prevalence and molecular epidemiology of mcr-1-positive Klebsiella pneumoniae in healthy adults from China.

OBJECTIVES: To investigate the nationwide prevalence of mcr-1-positive Klebsiella pneumoniae (MCRPKP) strains among healthy adults in China and identify their phenotypic and genomic characterizations. METHODS: A total of 7401 rectal swab samples were collected from healthy individuals in 30 hospitals located in 30 provinces and municipalities of mainland China in 2016. Colistin-resistant bacteria were enriched in colistin-supplemented lysogeny broth. MCRPKP strains were isolated and characterized with MALDI-TOF MS, PCR analysis and antimicrobial susceptibility testing. The genomic characteristics of MCRPKP strains were determined by WGS and bioinformatics analysis. RESULTS: Seven MCRPKP strains and one mcr-1-positive Klebsiella variicola strain were selectively isolated from six locales (three from Henan and one from each of Tianjin, Jiangxi, Yunnan, Gansu and Tibet). Antimicrobial susceptibility testing results indicated that all mcr-1-positive strains were susceptible to meropenem, aztreonam and ceftazidime/avibactam. WGS analysis suggested these strains belonged to seven distinct STs: ST15, ST1425, ST1462, ST273, ST307, ST391 and ST37-SLV. mcr-1 genes were carried by diverse plasmids, including IncHI2 (n = 3), IncX4 (n = 2), IncHI2/IncN (n = 1), IncFIB (n = 1) and one other plasmid type. Two ST15 strains harboured both mcr-1 and mcr-8 genes, which has not been reported before. CONCLUSIONS: Our data indicated a low prevalence of mcr-1-positive Klebsiella strains (0.11%, 8/7401) in healthy individuals in mainland China and most of these strains remained susceptible to clinically important antibiotics. The prevalence and coexistence of mcr-1 and mcr-8 in K. pneumoniae may further threaten public health through either the food chain or environmental routes.

Emergence of an Empedobacter falsenii strain harbouring a tet(X)-variant-bearing novel plasmid conferring resistance to tigecycline.

OBJECTIVES: To investigate the genomic and phenotypic characteristics of an MDR Empedobacter falsenii strain isolated from a Chinese patient, which was phenotypically resistant to all last-line antibiotics (carbapenems, colistin and tigecycline). METHODS: Species identity was determined by MALDI-TOF MS analysis. The complete genome sequence of the isolate was determined by WGS and the genetic elements conferring antimicrobial resistance were determined. The origin of this strain was tracked by phylogenetic analysis. RESULTS: The E. falsenii strain was genetically most closely related to an Empedobacter sp. strain isolated from the USA. Members of E. falsenii are speculated to be intrinsically resistant to colistin. The carbapenem resistance of this strain was conferred by a chromosomal blaEBR-2 variant gene. Phylogenetic analysis indicated that the gene encoding the EBR ß-lactamase was widely distributed in Empedobacter spp. Tigecycline resistance was mediated by a tet(X) variant gene encoded by a non-conjugative and non-typeable plasmid. CONCLUSIONS: The MDR phenotype of the E. falsenii isolate was conferred by different mechanisms. Findings from us and others indicate that E. falsenii may serve as a reservoir for carbapenem and tigecycline resistance determinants.

Variability of serum phosphorus and its association with mortality among hemodialysis patients
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OBJECTIVE: To determine the relationship between the variability of serum phosphorus and mortality among maintenance hemodialysis (MHD) patients. MATERIALS AND METHODS: A total of 502 MHD cases were studied from the Shanghai Renal Registry Network. Serum phosphorus variability was indicated by a coefficient of variation (CV). According to the CV median of serum phosphorus, patients were divided into two groups: a high-variability group (CV ≥ 0.226 mmol/L) and a low-variability group (CV < 0.226 mmol/L). Average phosphorus ≤ 1.78 mmol/L was defined as the standard phosphorus group and serum phosphorus > 1.78 mmol/L was defined as the non-standard phosphorus group. The relationship between serum phosphorus variability and all-cause and cardiovascular disease (CVD) mortality was assessed. RESULTS: In the 502 MHD cases, the average age of patients was 63.9 ± 14.60 years, and dialysis vintage was 82.0 (43.0 - 139.0) months. 118 patients (23.5%) died, succumbing to all-cause mortality, while 64 patients (14.3%) died from CVD. The high-variability group had increased all-cause mortality (27.7% vs. 19.3%, p = 0.028). Death from CVD was increased in the high-variability group, but had no statistical significance (15.4% vs. 10.0%, p = 0.082). Cox regression analysis showed that older age, low hemoglobin levels, a higher phosphorus CV, and low serum albumin were independent risk factors for all-cause and CVD mortality. The standard group with low-phosphorus variability had a decreased mortality compared with the non-standard group with high variability (15.3 vs. 29.2%, p = 0.047 and 6.0 vs. 15.0%, p = 0.033, respectively). The Kaplan-Meier method revealed that patients with low phosphorus variability had a decreased all-cause and CVD mortality (p = 0.023 and p = 0.047, respectively) compared with high phosphorus variability patients. CONCLUSION: Higher phosphorus CV was independently correlated with all-cause and CVD mortality. Low phosphorus variability with on-target levels resulted in decreased patient mortality. Thus, stable serum phosphorus levels may improve survival in MHD patients.
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The relationship between survival rate and intradialytic blood pressure changes in maintenance hemodialysis patients.

OBJECTIVE: The objective of this study is to investigate the relationship between blood pressure changes and all-cause mortality, and between blood pressure changes and cardiovascular mortality, for maintenance hemodialysis (MHD) patients during dialysis. METHODS: Data regarding general condition, biochemical indices, and survival prognosis of MHD patients who were treated at the Shanghai Jiao Tong University School of Medicine-affiliated Renji Hospital from July 2007 to December 2012 were collected, in order to evaluate the relationship between patients' blood pressure changes during hemodialysis and mortality. RESULTS: Among 364 patients, with an average age of 63.07 ± 13.93 years, an average dialysis vintage of 76.00 (range, 42.25-134.00) months, and a follow-up time of 54.86 ± 19.84 months, there were 85 cases (23.4%) of all-cause death and 46 cases (14.2%) of cardiovascular death. All-cause mortality and cardiovascular mortality were lowest (OR, 0.324 and 0.335; 95% CI, 0.152-0.692 and 0.123-0.911; p value, .004 and .032, respectively) in patients whose systolic blood pressure difference (ΔSBP) before and after dialysis was between 7.09 and 14.25 mmHg. Kaplan-Meier analysis indicated that both all-cause mortality and cardiovascular mortality were markedly increased for patients with ΔSBPless than -0.25 mmHg (p value, .001 and .044, respectively). Cox regression analysis showed that ΔSBP< -0.25 mmHg, hemoglobin concentration, Kt/v and albumin were independent risk factors for all-cause mortality in MHD patients. CONCLUSIONS: MHD patients whose blood pressure increased significantly after hemodialysis had a higher risk of dying; ΔSBP, hemoglobin concentration, Kt/v and albumin were independent risk factors for all-cause mortality in MHD patients.

Urinary exosomal mRNAs as biomarkers for predicting the therapeutic effect of renin-angiotensin system inhibitors in IgA nephropathy patients.

BACKGROUND: Renin-angiotensin system inhibitors (RASi) treatment is the basic therapy for IgA nephropathy (IgAN) patients. However, there is few of biomarker that can predict the efficacy of RASi. This study aimed to find urinary exosomal mRNAs related to the therapeutic effect of RASi in the treatment of proteinuria in IgAN patients. METHODS: We divided IgAN patients in screening cohort into A1 (proteinuria increase at 3 months), B1 (proteinuria decrease less than 50 % at 3 months), C1 (proteinuria decrease more than 50 % at 3 months) groups according to changes of proteinuria after treatment. The urinary exosomes were collected before biopsy, RNAs were extracted and analyzed with the microarray assay. The candidate genes were screened by differentially expressed genes (DEGs) analysis and then validated by quantitative real-time polymerase chain reaction (qPCR) in a validation cohort. A receiver operating characteristic (ROC) curve was used to evaluate gene performance in predicting therapeutic effect on RASi reducing proteinuria in IgAN patients. RESULTS: ECE1 and PDE1A mRNAs were significantly different among the three groups, and were gradually decreased among A1, B1 and C1 groups. In the validation cohort, the level of urinary exosomal ECE1 and PDE1A mRNAs were also significantly lower in A2 group compared with C2 group(ECE1, P < 0.001;PDE1A, P < 0.01). Besides, the level of ECE1 mRNA was also lower in B2 group compared with C2 group (P < 0.01). The ROC curve verified that urinary exosomal ECE1 and PDE1A gene level predicted RASi efficacy in IgAN patients with area under curve (AUC) 0.68 and 0.63 respectively. CONCLUSION: Urinary exosomal ECE1 and PDE1A mRNAs expression can serve as potential biomarkers for predicting the RASi efficacy to reduce proteinuria in IgAN patients.

The presence of exudative thickening of Bowman's capsule predict poor prognosis in diabetic kidney disease.

BACKGROUND: The relationship between Bowman's capsule thickening and progression of diabetic kidney disease (DKD) remains uncertain. METHODS: Renal biopsy specimens from 145 DKD patients and 20 control subjects were evaluated for Bowman's capsule thickness. Immunohistochemical staining assessed col4α2, laminin ß1, and albumin expression. In a discovery cohort of 111 DKD patients with eGFR ≥ 30 ml/min/1.73 m2, thickening was classified as fibrotic or exudative. The composite endpoint included CKD stage 5, dialysis initiation, and renal disease-related death. Prognosis was analyzed using Kaplan-Meier and Cox regression analyses. Two validation cohorts were included. RESULTS: Three types of thickening were observed: fibrotic, exudative, and periglomerular fibrosis. Parietal epithelial cell matrix protein accumulation contributed to fibrotic thickening, while albumin was present in exudative thickening. Bowman's capsule was significantly thicker in DKD patients (5.74 ± 2.09 µm) compared to controls (3.38 ± 0.43 µm, P < 0.01). In discovery cohort, the group of exudative thickning had a poorer prognosis(median time 20 months vs 57 months, P = 0.000). Cox multivariate analysis revealed that exudative thickening of Bowman's capsule were associated with a poor prognosis. The validation cohorts confirmed the result. CONCLUSIONS: Various mechanisms contribute to Bowman's capsule thickening in DKD. The proportion of exudative thickening may serve as a valuable prognostic indicator for DKD patients.

P2X7R/AKT/mTOR signaling mediates high glucose-induced decrease in podocyte autophagy.

Diabetic nephropathy is one of the leading causes of end-stage renal disease worldwide. In our study we found that Adenosine triphosphate (ATP) content was significantly increased in the urine of diabetic mice. We examined the expression of all purinergic receptors in the renal cortex and found that only purinergic P2X7 receptor (P2X7R) expression was significantly increased in the renal cortex of wild-type diabetic mice and that the P2X7R protein partially co-localized with podocytes. Compared with P2X7R(-/-) non-diabetic mice, P2X7R(-/-) diabetic mice showed stable expression of the podocyte marker protein podocin in the renal cortex. The renal expression of microtubule associated protein light chain 3 (LC-3II) in wild-type diabetic mice was significantly lower than in wild-type controls, whereas the expression of LC-3II in the kidneys of P2X7R(-/-) diabetic mice was not significantly different from that of P2X7R(-/-) non-diabetic mice. In vitro, high glucose induced an increase in p-Akt/Akt, p-mTOR/mTOR and p62 protein expression along with a decrease in LC-3II levels in podocytes, whereas after transfection with P2X7R siRNA, Phosphorylated protein kinase B (p-Akt)/Akt, Phosphorylated mammalian target of rapamycin (p-mTOR)/mTOR, and p62 expression were restored and LC-3II expression was increased. In addition, LC-3II expression was also restored after inhibition of Akt and mTOR signaling with MK2206 and rapamycin, respectively. Our results suggest that P2X7R expression is increased in podocytes in diabetes, and that P2X7R is involved in the inhibition of podocyte autophagy by high glucose, at least in part through the Akt-mTOR pathway, thereby exacerbating podocyte damage and promoting the onset of diabetic nephropathy. Targeting P2X7R may be a potential treatment for diabetic nephropathy.

Emergence of the clinical rdar morphotype carbapenem-resistant and hypervirulent Klebsiella pneumoniae with enhanced adaption to hospital environment.

Klebsiella pneumoniae has evolved into strains of various phenotypes that pose a grave threat to human health in the past few decades. This study investigated a novel morphotype of K. pneumoniae with enhanced adaption to the hospital environment. Clinical K. pneumoniae were characterized by different genotypic and phenotypic tests. Gene knockout and complementation experiments were used to confirm the genetic changes that led to the morphological changes. ST15 carbapenem-resistant and hypervirulent (CR-hvKP) clinical strains with the "red, dry and rough" (rdar) morphotype were increasingly detected in hospitals in China. Strains with the rdar phenotype were found to be less virulent compared with that with typical morphologies but exhibit enhanced ability to adhere to the surface of various materials, and hence a dramatically increased rate of survival on various materials commonly found in the hospital environment. Comparative genomics analysis and gene function studies suggested the rdar morphotype was due to a G579D substitution in the BcsA protein which enabled the strain to produce a large amount of cellulose. These findings show evolutional phenotypic change enables K. pneumoniae strains to better survive both in human and hospital environments, facilitating its persistence and further dissemination.

HIF1α-BNIP3-mediated mitophagy protects against renal fibrosis by decreasing ROS and inhibiting activation of the NLRP3 inflammasome.

Chronic kidney disease affects approximately 14.3% of people worldwide. Tubulointerstitial fibrosis is the final stage of almost all progressive CKD. To date, the pathogenesis of renal fibrosis remains unclear, and there is a lack of effective treatments, leading to renal replacement therapy. Mitophagy is a type of selective autophagy that has been recognized as an important way to remove dysfunctional mitochondria and abrogate the excessive accumulation of mitochondrial-derived reactive oxygen species (ROS) to balance the function of cells. However, the role of mitophagy and its regulation in renal fibrosis need further examination. In this study, we showed that mitophagy was induced in renal tubular epithelial cells in renal fibrosis. After silencing BNIP3, mitophagy was abolished in vivo and in vitro, indicating the important effect of the BNIP3-dependent pathway on mitophagy. Furthermore, in unilateral ureteral obstruction (UUO) models and hypoxic conditions, the production of mitochondrial ROS, mitochondrial damage, activation of the NLRP3 inflammasome, and the levels of αSMA and TGFß1 increased significantly following BNIP3 gene deletion or silencing. Following silencing BNIP3 and pretreatment with mitoTEMPO or MCC950, the protein levels of αSMA and TGFß1 decreased significantly in HK-2 cells under hypoxic conditions. These findings demonstrated that HIF1α-BNIP3-mediated mitophagy played a protective role against hypoxia-induced renal epithelial cell injury and renal fibrosis by reducing mitochondrial ROS and inhibiting activation of the NLRP3 inflammasome.

Paxlovid for hospitalized COVID-19 patients with chronic kidney disease.

BACKGROUND: COVID-19 causes significant mortality during the recent pandemic. Data regarding the effectiveness of Paxlovid on COVID-19 patients with chronic kidney disease (CKD, eGFR <90 ml/min) are limited. METHODS: A retrospective cohort study was performed on the clinical data of the hospitalized adult patients with confirmed COVID-19 infection collected at Renji Hospital from April 7, 2022 to June 21, 2022. The association of Paxlovid treatment with early (within 5 days post diagnosis) or late (5 days or later post diagnosis) initiation time with clinical outcomes was assessed by Cox proportional hazards regression model with time-dependent covariates. RESULT: 1279 of 2387 enrollees were included in the study. Patients with early initiation of Paxlovid had a lower all-cause death rate compared to those with late initiation or without Paxlovid treatment (P = 0.046). For the CKD patients with Charlson comorbidity index (CCI) > 7, the early initiation of Paxlovid was associated with a lower all-cause death rate compared to the later initiation or the lack of Paxlovid treatment (P = 0.041). Cox regression analyses revealed that eGFR (HR 4.21 [95%, CI 1.62-10.99]), Paxlovid treatment (0.32 [0.13-0.77]), CCI (4.32 [1.64-11.40]), ICU admission (2.65 [1.09-6.49]), hsCRP (3.88 [1.46-7.80]), chronic liver disease (4.02 [1.09-14.85]) were the independent risk factors for all-cause death for CKD patients after adjusting for demographics and biochemical indexes. CONCLUSIONS: All-cause death, invasive ventilation, and ICU admission were all significantly lowered by an early initiation of Paxlovid treatment in COVID-19 patients with severe CKD.

Nirmatrelvir/Ritonavir for hemodialysis patients with COVID-19.

Background: Hemodialysis patients have a high risk of severe/critical COVID-19 and related high mortality, but nirmatrelvir/ritonavir is not recommended for hemodialysis patients with COVID-19 infection because of lack of evidence of safety. Objectives: Our study aims to evaluate the minimum plasma concentration (Cmin) of nirmatrelvir and its safety of different doses of nirmatrelvir/ritonavir in hemodialysis patients with mild COVID-19. Method: This was a prospective, two step, nonrandomized, open-label study. Participants were treated with nirmatrelvir 150 mg or 300 mg once a day (another 75 mg or 150 mg supplied after hemodialysis) and ritonavir 100 mg twice daily for 5 days, respectively. The primary outcome was the safety of nirmatrelvir/ritonavir, including the Cmin of nirmatrelvir and the number of adverse events (AE). The secondary outcome was the time of viral elimination in hemodialysis patients. Results: Adverse events were happened in 3 and 7 participants in the step 1 and step 2 group, respectively (p = 0.025). Among them, 2 and 6 participants were identified as drug-related adverse events (p = 0.054). No SAE or liver function damage happened. The Cmin of nirmatrelvir in step 1 and step 2 group were 5,294.65 ± 2,370.59 ng/mL and 7,675.67 ± 2,745.22 ng/mL (p = 0.125). The Cmin of the control group was 2,274.10 ± 1,347.25 ng/mL (p = 0.001 compared to step 2 and p = 0.059 compared to step 1). Compared to hemodialysis patients without nirmatrelvir/ritonavir, there were no statistical differences in overall viral elimination time (p = 0.232). Conclusion: In our study, two doses of nirmatrelvir/ritonavir appeared to be excessive for hemodialysis patients. Although all of the patients tolerated 5-day administration, nearly half of the patients experienced drug-related adverse events. In addition, the medication group did not show a significant advantage in the time of viral elimination.

Escherichia coli carrying IncI2 plasmid-mediated mcr-1 genes in crested ibis (Nipponia nippon).

Antimicrobial resistance is a quintessential One Health issue, among the most serious 21st century global threats in human and veterinary medicine. Wild animals are usually not directly exposed to clinically relevant antibiotics; however, antibacterial resistance in wild animals has been increasingly reported worldwide in parallel to the situation in human and veterinary medicine. In this work, we collected 100 fecal samples from the crested ibis protected areas. A total of eight Escherichia coli (E. coli) isolates positive for mcr-1 were obtained, and all of them were analyzed using WGS (whole genome sequencing). The WGS analysis showed that the isolates were assigned to four different sequence types (ST) overall. The antibiotic susceptibility profile showed that of eight E. coli isolates, six strains exhibited resistance to tetracycline and all mcr-1-positive E. coli (MCREC) strains showed resistance to colistin. Our findings importantly document the epidemic spread of MCREC in crested ibis in China.