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.

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.

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.

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.

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.

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.

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.

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.

Genomic Shift in Population Dynamics of mcr-1-positive Escherichia coli in Human Carriage.

Emergence of the colistin resistance gene, mcr-1, has attracted worldwide attention. Despite the prevalence of mcr-1-positive Escherichia coli (MCRPEC) strains in human carriage showing a significant decrease between 2016 and 2019, genetic differences in MCRPEC strains remain largely unknown. We therefore conducted a comparative genomic study on MCRPEC strains from fecal samples of healthy human subjects in 2016 and 2019. We identified three major differences in MCRPEC strains between these two time points. First, the insertion sequence ISApl1 was often deleted and the percentage of mcr-1-carrying IncI2 plasmids was increased in MCRPEC strains in 2019. Second, the antibiotic resistance genes (ARGs), aac(3)-IVa and blaCTX-M-1, emerged and coexisted with mcr-1 in 2019. Third, MCRPEC strains in 2019 contained more virulence genes, resulting in an increased proportion of extraintestinal pathogenic E. coli (ExPEC) strains (36.1%) in MCRPEC strains in 2019 compared to that in 2016 (10.5%), implying that these strains could occupy intestinal ecological niches by competing with other commensal bacteria. Our results suggest that despite the significant reduction in the prevalence of MCRPEC strains in humans from 2016 to 2019, MCRPEC exhibits increased resistance to other clinically important ARGs and contains more virulence genes, which may pose a potential public health threat.

Effects of vitamin D supplementation during pregnancy on bone health and offspring growth: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Whether vitamin D supplementation during pregnancy is beneficial to bone health and offspring growth remains controversial. Moreover, there is no universal agreement regarding the appropriate dose and the time of commencement of vitamin D supplementation during pregnancy. OBJECTIVE: We aimed to systematically review the effects of vitamin D supplementation during pregnancy on bone development and offspring growth. METHODS: A literature search for randomized controlled trials (RCTs) was performed in 7 electronic databases to identify relevant studies about the effects of vitamin D supplementation during pregnancy on bone development and offspring growth from inception to May 22, 2022. A Cochrane Risk Assessment Tool was used for quality assessment. Vitamin D supplementation was compared with placebo or standard supplements. The effects are presented as the mean differences (MDs) with 95% CIs. The outcomes include bone mineral content (BMC), bone mineral density (BMD), bone area (BA), femur length (FL) and humeral length (HL); measurement indicators of growth, including length, weight and head circumference; and secondary outcome measures, including biochemical indicators of bone health, such as the serum 25(OH)D concentration. Additionally, subgroup analyses were carried out to evaluate the impact of different doses and different initiation times of supplementation with vitamin D. RESULTS: Twenty-three studies with 5390 participants met our inclusion criteria. Vitamin D supplementation during pregnancy was associated with increased humeral length (HL) (MD 0.13, 95% CI 0.06, 0.21, I2 = 0, P = 0.0007) during the fetal period (third trimester). Vitamin D supplementation during pregnancy was associated with a significantly increased length at birth (MD 0.14, 95% CI 0.04, 0.24, I2 = 24%, P = 0.005) and was associated with a higher cord blood 25(OH)D concentration (MD 48.74, 95% CI 8.47, 89.01, I2 = 100%, P = 0.02). Additionally, subgroup analysis revealed that birth length was significantly higher in the vitamin D intervention groups of ≤1000 IU/day and ≥4001 IU/day compared with the control group. Prenatal (third trimester) vitamin D supplementation was associated with a significant increase in birth length, while prenatal (second trimester) vitamin D supplementation was associated with a significant increase in birth weight. CONCLUSION: Vitamin D supplementation during pregnancy may be associated with increased humeral length (HL) in the uterus, increased body length at birth and higher cord blood 25(OH)D concentration. Evidence of its effect on long-term growth in children is lacking. Additional rigorous high-quality, long-term and larger randomized trials are required to more fully investigate the effects of vitamin D supplementation during pregnancy.

Distribution and spread of the mobilised RND efflux pump gene cluster tmexCD-toprJ in clinical Gram-negative bacteria: a molecular epidemiological study.

BACKGROUND: TMexCD1-TOprJ1, which is associated with phenotypic resistance to multiple classes of antibiotics, is a transmissible resistance-nodulation-division (RND) family efflux pump. However, the prevalence and genomic and phenotypic characteristics of clinical isolates with this important resistance determinant are poorly understood. In this study, we aimed to survey tmexCD-toprJ among clinical Gram-negative isolates collected from hospitals in China between 1991 and 2020 and characterise tmexCD-toprJ-positive clinical isolates. METHODS: We conducted online data retrieval and active nationwide surveillance in China to screen tmexCD-toprJ-positive strains. We characterised tmexCD-toprJ-positive clinical strains for their antimicrobial susceptibility, genetic and functional characteristics, and the potential inter-species transmission route of tmexCD-toprJ with whole genome sequencing and bioinformatics analyses. The function of tmexCD-toprJ in Pseudomonas sp and Proteus sp was investigated by tmexD gene knockdown using an isopropylthio-ß-galactoside-inducible CRISPR interference system. FINDINGS: Data retrieval obtained 53 strains carrying tmexCD-toprJ, comprising 32 Pseudomonas spp, 11 Klebsiella pneumoniae, one Aeromonas spp, one Citrobacter freundii, and one uncultured bacterium from diverse niches. 48 (0·64%) of 7517 clinical isolates from China, including seven Klebsiella spp, one Proteus mirabilis, and 40 Pseudomonas spp, carried tmexCD-toprJ. These isolates exhibited multidrug resistance phenotypes and co-harboured resistance genes, such as mcr and carbapenemases genes. tmexCD-toprJ was encoded on both plasmids and chromosomes in all Klebsiella spp that carried plasmid-borne tmexCD-toprJ (n=7), P mirabilis carried chromosome-borne tmexCD-toprJ, and Pseudomonas spp carried either plasmid-borne (n=19) or chromosome-borne (n=21) ones. tmexCD-toprJ had undergone clonal and horizontal transmission among clinical pathogens. Eight different types of genetic context of tmexCD-toprJ were identified, each of which was associated with different mobile elements, including IntI, IS6100, TnAs1-like, ISRor5, ISVsa3, ISCfr-like, Tn5393, and IS222-like, which might facilitate its transmission. Knockdown of tmexD led to a four times decrease in tigecycline minimum inhibitory concentrations in both Pseudomonas spp and Proteus spp. INTERPRETATION: Our study provides evidence to suggest that tmexCD-toprJ contributes to the antimicrobial resistance phenotypes in different bacterial species. tmexCD-toprJ has disseminated among diverse species of clinical pathogens, which warrants timely monitoring in clinical pathogens. FUNDING: National Natural Science Foundation of China, Guangdong Major Project of Basic and Applied Basic Research, Natural Science Foundation of Jiangsu Province.

Emergence of an Extensive Drug Resistant Pseudomonas aeruginosa Strain of Chicken Origin Carrying blaIMP-45, tet(X6), and tmexCD3-toprJ3 on an IncpRBL16 Plasmid.

This study reports an extensively drug resistant Pseudomonas aeruginosa strain PA166-2 which was of chicken origin and carrying blaIMP-45, tet(X6) and tmexCD3-toprJ3 on a single plasmid. The strain was characterized by antimicrobial susceptibility testing, resistance gene screening, conjugation assay, whole-genome sequencing, and bioinformatics analysis. Strain PA166-2 was resistant to tigecycline and carbapenems. It belonged to ST313 and carried a plasmid pPA166-2-MDR, which belongs to the incompatibility group IncpRBL16. pPA166-2-MDR harbored a 78 Kb multidrug resistance (MDR) region carrying an array of antimicrobial resistance genes, including blaIMP-45, tet(X6), and tmexCD3-toprJ3. The gene blaIMP-45 was inserted into the backbone of plasmid pPA166-2-MDR within a class 1 integron, In786. tmexCD3-toprJ3 in plasmid pPA166-2-MDR was inserted in umuC, constituting the genetic context of ISCfr1-tnfxB3-tmexC3-tmexD3-toprJ3-△umuC. The genetic context of tet(X6) in this plasmid was identical to that of other reported plasmid-borne tet(X) variants, namely, tet(X6)-abh-guaA-ISVsa3. To the best of our knowledge, this is the first report of the cooccurrence of blaIMP-45, tet(X6), and tmexCD3-toprJ3 in one plasmid in Pseudomonas sp. The emergence of plasmid-mediated tigecycline resistance genes tmexCD3-toprJ3 and tet(X6), as well as carbapenemase genes from chickens expanded the global transmission of vital resistance genes. Findings from us and from others indicate that plasmids of the incompatibility group IncpRBL16 may serve as a reservoir for carbapenem and tigecycline resistance determinants. IMPORTANCE Pseudomonas aeruginosa is an opportunistic pathogen that causes infections that are difficult to treat. This study reported, for the first time, the occurrence of last-resort antibiotic resistance determinants blaIMP-45, tet(X6), and tmexCD3-toprJ3 on a single plasmid in P. aeruginosa from chickens. The P. aeruginosa strain belonged to ST313 and was resistant to last-line antibiotics, namely, carbapenems and tigecycline. The plasmid carrying the last-line resistance genes belonged to the incompatibility group IncpRBL16, which was reported to contain different profiles of accessory modules and thus carried diverse collections of resistance genes. The emergence of plasmid-mediated tigecycline resistance genes tmexCD3-toprJ3 and tet(X6), as well as carbapenemase genes, from chickens expanded the global transmission of vital resistance genes. The results in this study highlighted that IncpRBL16 plasmids may serve as a reservoir for the dissemination of resistance genes. Control measures should be implemented to prevent the further dissemination of such strains.

Carriage of the mcr-9 and mcr-10 genes in clinical strains of the Enterobacter cloacae complex in China: a prevalence and molecular epidemiology study.

OBJECTIVES: Enterobacter cloacae complex (ECC) is among the most common carbapenem-resistant Enterobacteriaceae (CRE) in China. The emergence of mcr has rendered CRE strains resistant to the last-line antibiotic colistin. This study investigated the prevalence of mcr-9 and mcr-10 in carbapenem-resistant ECC (CRECC) and carbapenem-susceptible ECC (CSECC) in China. METHODS: The CRECC and CSECC strains were collected from different regions of China. Antimicrobial susceptibility tests, conjugation experiments, whole genome sequencing, bioinformatic analysis, and quantitative RT-PCR were performed to understand the mechanisms of resistance and transmission of mcr in ECC. RESULTS: A total of 534 ECC were collected, among which 57 (10.7%) and 23 (4.3%) were positive for mcr-9 and mcr-10, respectively. The prevalence of mcr-9 in CRECC was significantly higher than that in CSECC (31.8% vs. 3.7%; P < 0.001), while the prevalence of mcr-10 in CRECC was significantly lower (0.8% vs. 5.5%; P < 0.05). Most mcr-9-positive strains (n = 45, 78.9%) exhibited multidrug-resistant phenotype, and four (17.4%) of the mcr-10-positive strains exhibited multi-drug resistance. Coexistence of mcr and carbapenemase genes was commonly observed, including 41 (71.9%) mcr-9-positive strains and one (4.3%) mcr-10-positive strain, and the possibility of co-transfer was confirmed by conjugation experiments. The mcr-positive ECC were highly diverse, while most mcr genes were plasmid-encoded, indicating the important role of plasmids in the transmission of mcr in ECC. Furthermore, the expression of mcr-9 was increased after induction by colistin. CONCLUSIONS: The widespread mcr genes and co-transfer with carbapenemase genes among ECC strains pose an urgent threat to public health.

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.

Auto-Segmentation Ultrasound-Based Radiomics Technology to Stratify Patient With Diabetic Kidney Disease: A Multi-Center Retrospective Study.

Background: An increasing proportion of patients with diabetic kidney disease (DKD) has been observed among incident hemodialysis patients in large cities, which is consistent with the continuous growth of diabetes in the past 20 years. Purpose: In this multicenter retrospective study, we developed a deep learning (DL)-based automatic segmentation and radiomics technology to stratify patients with DKD and evaluate the possibility of clinical application across centers. Materials and Methods: The research participants were enrolled retrospectively and separated into three parts: training, validation, and independent test datasets for further analysis. DeepLabV3+ network, PyRadiomics package, and least absolute shrinkage and selection operator were used for segmentation, extraction of radiomics variables, and regression, respectively. Results: A total of 499 patients from three centers were enrolled in this study including 246 patients with type II diabetes mellitus (T2DM) and 253 patients with DKD. The mean intersection-over-union (Miou) and mean pixel accuracy (mPA) of automatic segmentation of the data from the three medical centers were 0.812 ± 0.003, 0.781 ± 0.009, 0.805 ± 0.020 and 0.890 ± 0.004, 0.870 ± 0.002, 0.893 ± 0.007, respectively. The variables from the renal parenchyma and sinus provided different information for the diagnosis and follow-up of DKD. The area under the curve (AUC) of the radiomics model for differentiating between DKD and T2DM patients was 0.674 ± 0.074 and for differentiating between the high and low stages of DKD was 0.803 ± 0.037. Conclusion: In this study, we developed a DL-based automatic segmentation, radiomics technology to stratify patients with DKD. The DL technology was proposed to achieve fast and accurate anatomical-level segmentation in the kidney, and an ultrasound-based radiomics model can achieve high diagnostic performance in the diagnosis and follow-up of patients with DKD.

The Rapid Emergence of Ceftazidime-Avibactam Resistance Mediated by KPC Variants in Carbapenem-Resistant Klebsiella pneumoniae in Zhejiang Province, China.

Ceftazidime-avibactam (CAV) is a new treatment option against carbapenem-resistant Klebsiella pneumoniae (CRKP) infections. However, the rapid emergence of CAV resistance mediated by KPC variants has posed a severe threat to healthcare after its clinical application. The characteristics of CAV resistance in CRKP strains needs to be determined in China. A total of 477 CRKP isolates were collected from 46 hospitals in Zhejiang Province from 2018 to 2021. The results demonstrated that CAV had a potent activity against 94.5% of all CRKP (451/477, 95% CI: 93.0-96.1%) and 86.0% of CRKP strains carrying blaKPC genes (410/477, 95% CI: 83.5-88.4%). A total of 26 CAV-resistant strains were found. Among these strains, sixteen harbored metallo-ß lactamases, and two carried KPC-2 carbapenemase and mutated ompK35 and ompK36. Eight CRKP strains encoded KPC-33 or KPC-93, belonging to ST11, among which seven strains were detected in patients hospitalized in 2021 after exposure to CAV and one strain was associated with intra-hospital spread. CAV is a potent agent in vitro against CRKP strains. The rapid development of CAV resistance mediated by various KPC variants after a short period of CAV treatment has increased and brought difficulties in treating infections caused by CRKP strains, especially those belonging to ST11. The surveillance of bacterial resistance against CAV is highly recommended due to the steep development of CAV resistance and rapid evolution of KPC enzymes.

Epidemiological and genetic characteristics of clinical carbapenem-resistant Acinetobacter baumannii strains collected countrywide from hospital intensive care units (ICUs) in China.

Acinetobacter baumannii is one of the key Gram-negative pathogens that can cause serious nosocomial infections. In China, a large proportion of clinical A. baumannii strains are multidrug resistant, among which strains resistant to carbapenems are particularly worrisome, as infections caused by such strains may limit the choice of existing antibiotics. We conducted a nationwide and genome-based surveillance on the prevalence and antibiotic susceptibility profile of carbapenem-resistant A. baumannii (CRAB) strains collected from intensive care units (ICUs) in hospitals in different provinces and investigated the routes of transmission and mechanism of resistance by whole-genome sequencing and phylogenetic analysis. We found that CRAB strains were prevalent in 71.4% (55/77) of the ICUs surveyed. Clonal spread of CRAB was found in 37.6% (29/77) of ICUs and a total of 22 different clones were identified. Most clones were transmissible within one ICU, but up to six clones could be detected in at least three hospitals. In addition, carbapenem-hydrolysing class D ß-lactamases (CHDL) were found to be mainly responsible for carbapenem-resistance in A. baumannii and the ST2 global-clone is the predominant type of CRAB in China. Importantly, we found that CRAB isolates currently exhibited an extremely low rate of resistance to colistin (0.4%) and tigecycline (2.5%), but a high rate of resistance to ceftazidime-avibactam (70.2%). Findings in this work shall facilitate development of appropriate antimicrobial regimens for treatment of CRAB infections. Further surveillance and research on the evolutionary and epidemiological features of clinical CRAB strains are necessary.

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.