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991.
992.
Brian J. Werth Nathaniel K. Ashford Kelsi Penewit Adam Waalkes Elizabeth A. Holmes Dylan H. Ross Tianwei Shen Kelly M. Hines Stephen J. Salipante Libin Xu 《Clinical microbiology and infection》2021,27(6):910.e1-910.e8
ObjectivesDalbavancin is a lipoglycopeptide active against methicillin-resistant Staphylococcus aureus (MRSA). Its long half-life (8.5–16 days) allows for once-weekly or single-dose treatments but could prolong the mutant selection window, promoting resistance and cross-resistance to related antimicrobials such as vancomycin. The objective of this study was to evaluate the capacity of post-distributional pharmacokinetic exposures of dalbavancin to select for resistance and cross-resistance in MRSA.MethodsWe simulated average, post-distributional exposures of single-dose (1500 mg) dalbavancin (fCmax 9.9 μg/mL, β-elimination t1/2 204 h) in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model for 28 days (672 h) against five MRSA strains and one methicillin-susceptible strain (MSSA). Samples were collected at least daily, and surviving colonies were enumerated and screened for resistance on drug-free and dalbavancin-supplemented medium respectively. Isolates from resistance screening plates were subjected to whole-genome sequencing (WGS) and susceptibly testing against dalbavancin, vancomycin, daptomycin, and six β-lactams with varying penicillin-binding protein (PBP) affinities.ResultsDalbavancin was bactericidal against most strains for days 1–4 before regrowth of less susceptible subpopulations occurred. Isolates with eight-fold increases in dalbavancin MIC were detected as early as day 4 but increased 64–128-fold in all models by day 28. Vancomycin and daptomycin MICs increased 4–16-fold, exceeding the susceptibly breakpoints for both antibiotics; β-lactam MICs generally decreased by two-to eight-fold, suggesting a dalbavancin–β-lactam seesaw effect, but increased by eight-fold or more in certain isolates. Resistant isolates carried mutations in a variety of genes, most commonly walKR, apt, stp1, and atl.ConclusionsIn our in vitro system, post-distributional dalbavancin exposures selected for stable mutants with reduced susceptibility to dalbavancin, vancomycin, and daptomycin, and generally increased susceptibility to β-lactams in all strains of MRSA tested. The clinical significance of these findings remains unclear, but created an opportunity to genotype a unique collection of dalbavancin-resistant strains for the first time. Mutations involved genes previously associated with vancomycin intermediate susceptibility and daptomycin non-susceptibility, most commonly walKR-associated genes. 相似文献
993.
Kai Yang Jie Shen Fu-Qing Tan Xiang-Yi Zheng Li-Ping Xie 《International journal of medical sciences》2021,18(13):3039
Small double-stranded RNAs (dsRNAs) have been proved to effectively up-regulate the expression of particular genes by targeting their promoters. These small dsRNAs were also termed small activating RNAs (saRNAs). We previously reported that several small double-stranded RNAs (dsRNAs) targeting the PRKC apoptosis WT1 regulator (PAWR) promoter can up-regulate PAWR gene expression effectively in human cancer cells. The present study was conducted to evaluate the antitumor potential of PAWR gene induction by these saRNAs in bladder cancer. Promisingly, we found that up-regulation of PAWR by saRNA inhibited the growth of bladder cancer cells by inducing cell apoptosis and cell cycle arrest which was related to inhibition of anti‑apoptotic protein Bcl-2 and inactivation of the NF-κB and Akt pathways. The activation of the caspase cascade and the regulation of cell cycle related proteins also supported the efficacy of the treatment. Moreover, our study also showed that these saRNAs cooperated with cisplatin in the inhibition of bladder cancer cells. Overall, these data suggest that activation of PAWR by saRNA may have a therapeutic benefit for bladder cancer. 相似文献
994.
995.
Huilong Chen Xinjie Li Tuohutaerbieke Marmar Qiang Xu Jing Tu Tong Li Jun Han Dong Xu Tao Shen 《International journal of medical sciences》2021,18(6):1474
Background: For coronavirus disease 2019 (COVID-19), early identification of patients with serious symptoms at risk of critical illness and death is important for personalized treatment and balancing medical resources.Methods: Demographics, clinical characteristics, and laboratory tests data from 726 patients with serious COVID-19 at Tongji Hospital (Wuhan, China) were analyzed. Patients were classified into critical group (n = 174) and severe group (n= 552), the critical group was sub-divided into survivors (n = 47) and non-survivors (n = 127).Results: Multivariable analyses revealed the risk factors associated with critical illness in serious patients were: Advanced age, high respiratory rate (RR), high lactate dehydrogenase (LDH) level, high hypersensitive cardiac troponin I (hs-cTnI) level, and thrombocytopenia on admission. High hs-cTnI level was the independent risk factor of mortality among critically ill patients in the unadjusted and adjusted models. ROC curves demonstrated that hs-cTnI and LDH were predictive factors for critical illness in patients with serious COVID-19 whereas procalcitonin and D-Dimer with hs-cTnI and LDH were predictive parameters in mortality risk.Conclusions: Advanced age, high RR, LDH, hs-cTnI, and thrombocytopenia, constitute risk factors for critical illness among patients with serious COVID-19, and the hs-cTnI level helps predict fatal outcomes in critically ill patients. 相似文献
996.
BackgroundIron is closely related to metabolism. However, the relationship between iron and hepatic steatosis has not been fully elucidated.ObjectiveWe aimed to investigate the triangular relationship between iron and hepatic steatosis and laparoscopic sleeve gastrectomy (LSG) in patients with obesity.MethodsA total of 297 patients with obesity and 43 healthy individuals with a normal BMI were enrolled. Eighty-two patients underwent LSG. Anthropometrics, glucose-lipid metabolic markers, and hepatic steatosis assessed by FibroScan (CAP value and E value) were measured at baseline, and again at follow-up time intervals of 6 months and 1 year after surgery.Results(1) Iron was significantly higher in patients with obesity or overweight than in the individuals with normal BMI (8.18 ± 1.47 vs. 7.46 ± 0.99 mmol/L, p = 0.002). Iron was also higher in subjects with high blood pressure, dyslipidemia, and hyperuricemia than non-corresponding disorders (all p < 0.05). Moreover, iron was significantly higher in the severe than mild or moderate non-alcoholic fatty liver disease (NAFLD) group (p = 0.046 and 0.018). (2) Iron was positively associated with body weight, BMI, waist-to-hip ratio, uric acid, liver enzymes, postprandial blood glucose, fasting insulin, HOMA-IR, triglycerides, free fatty acid, and hepatic steatosis (CAP value), and negatively associated with high-density lipoprotein cholesterol (all p < 0.05). Iron was also positively associated with the visceral adipose area in patients with obesity and negatively associated with the subcutaneous adipose area in patients with overweight (all p < 0.05). (3) Iron levels and CAP values were decreased gradually 6 months and 1 year after surgery (all p < 0.05).ConclusionsOverall, our results indicated that iron is associated with hepatic steatosis in obesity. The iron level was significantly higher in patients with severe NAFLD than with mild or moderate NAFLD. LSG may reduce iron levels while improving fat deposition in the liver. 相似文献
997.
Jie Zou Gang Shen Wen Qiang Yuan Yan Zhu Wang Xia Li 《International journal of immunogenetics》2021,48(1):8-15
The present study aimed to analyse the frequencies of human leukocyte antigen HLA‐ABCDQB1 and HLA‐DRB1 alleles and haplotypes in a subset of 3,732 Han population from Hubei of China. All samples were typed in the HLA‐ABCDQB1 and HLA‐DRB1 loci using the sequence‐based typing method; subsequently, the HLA polymorphisms were analysed. A total of 47 HLA‐A, 89 HLA‐B, 43 HLA‐C, 49 HLA‐DRB1 and 24 HLA‐DQB1 alleles were identified in the Hubei Han population. The top three most frequent alleles in the HLA‐ABCDQB1 and HLA‐DRB1 were A*11:01 (0.2617), A*24:02 (0.1590), A*02:07 (0.1281); B*46:01 (0.1502), B*40:01 (0.1409) and B*58:01 (0.0616); C*01:02 (0.2023), C*07:02 (0.1691) and C*03:04 (0.1175); and DQB1*03:01 (0.2000), DQB1*03:03 (0.1900), DQB1*06:01 (0.1187); DRB1*09:01 (0.1790), DRB1*15:01 (0.1062) and DRB1*12:02 (0.0841), respectively. Meanwhile, the three most frequent two‐loci haplotypes were A*02:07‐C*01:02 (0.0929), B*46:01‐C*01:02 (0.1366) and DQB1*03:03‐DRB1*09:01 (0.1766). The three most frequent three‐loci haplotypes were A*02:07‐B*46:01‐C*01:02 (0.0883), B*46:01‐DQB1*03:03‐DRB1*09:01 (0.0808) and C*01:02‐DQB1*03:03‐DRB1*09:01 (0.0837). The three most frequent four‐loci haplotypes were A*02:07‐B*46:01‐C*01:02‐DQB1*03:03 (0.0494), B*46:01‐DRB1*09:01‐C*01:02‐DQB1*03:03 (0.0729) and A*02:07‐B*46:01‐DQB1*03:03‐DRB1*09:01 (0.0501). The most frequent five‐loci haplotype was A*02:07‐B*46:01‐C*01:02‐DQB1*03:03‐DRB1*09:01 (0.0487). Heat maps and multiple correspondence analysis based on the frequencies of HLA specificity indicated that the Hubei Han population might be described into Southern Chinese populations. Our results lay a certain foundation for future population studies, disease association studies and donor recruitment strategies. 相似文献
998.
Fei Yang Danhua Shen Junping Shi 《International journal of clinical and experimental pathology》2021,14(5):662
Background: NUT carcinoma is a rare aggressive squamous cell carcinoma subtype genetically characterized by NUTM1 rearrangements. NUT carcinoma can be easily misdiagnosed as an undifferentiated carcinoma or Ewing sarcoma due to its primitive differentiation. Case presentation: We report a case of renal-derived NUT carcinoma diagnosed as a malignant small round-cell tumor resembling Ewing sarcoma/primitive neuroectodermal tumor where the diagnosis was revised to NUT carcinoma with a characteristic NUTM1 rearrangement based on next-generation sequencing (NGS). The patient received a standard NUT carcinoma treatment after recurrence but died of first-line chemotherapy failure due to advanced neoplasm progression. Conclusion: Routine NUT immunohistochemistry staining, NGS, and/or fluorescent in situ hybridization for poorly differentiated carcinoma and sarcoma can help avoid misdiagnosis of NUT carcinoma-related tumors, allowing patients to benefit from bromodomain and extra-terminal motif inhibitor therapy. 相似文献
999.
Zhiwen Shen Hui Xu Wen Song Chuwen Hu Mingyan Guo Jinfeng Li Junhua Li 《CNS Neuroscience & Therapeutics》2021,27(7):842-856
IntroductionThe incidence of perioperative neurocognitive disorders (PND) is higher in the elderly patients undergoing surgery. Microglia activation‐mediated neuroinflammation is one of the hallmarks of PND. Galectin‐1 has been identified as a pivotal modulator in the central nervous system (CNS), while the role of galectin‐1 in PND induced by microglia‐mediated neuroinflammation is still undetermined.MethodsAn exploratory laparotomy model anesthetized with isoflurane was employed to investigate the role of galectin‐1 on PND in aged mice. Open field test and Morris water maze were used to test the cognitive function 3‐ or 7‐days post‐surgery. The activation of microglia in the hippocampus of aged mice was tested by immunohistochemistry. Western blot, enzyme‐linked immunosorbent assay (ELISA), and quantitative real‐time polymerase chain reaction (qRT‐PCR) were employed to elucidate the underlying mechanisms.ResultsGalectin‐1 attenuated the cognitive dysfunction induced by surgery in aged mice and inhibited microglial activity. Moreover, galectin‐1 decreased the expression level of inflammatory proteins (interleukin‐1β, interleukin‐6, and tumor necrosis factor‐α), and prevented neuronal loss in the hippocampus. Galectin‐1 inhibited the inflammation of BV2 microglial cells induced by lipopolysaccharide via decreasing the translocation of NF‐κB p65 and c‐Jun, while this kind of inhibition was rescued when overexpressing IRAK1.ConclusionOur findings provide evidence that galectin‐1 may inhibit IRAK1 expression, thus suppressing inflammatory response, inhibiting neuroinflammation, and improving ensuing cognitive dysfunction. Collectively, these findings unveil that galectin‐1 may elicit protective effects on surgery‐induced neuroinflammation and neurocognitive disorders. 相似文献
1000.
目的调查分析独立学院大学生精神疾病发病特点,为开展校园心理干预提供依据。方法选取某独立学院5年制23590名新生作为研究对象,采用症状自评量表(SCL-90)、《家庭环境量表》(FES-CV)及校园心理干预系列调查表进行测评。结果独立学院学生家庭环境与中国常模比较有统计学意义(t=-2.74,P<0.01);症状自评量表(SCL-90)单因子分≥3.0预警人数平均比例4.2%;以专科诊断为依据,精神疾病67例,占入学人数的0.28%;大一年级发病52例,占总病例的77.61%;在疾病发现环节,辅导员报告40例,占总病例的59.70%。结论实施校园心理干预策略,可降低大学生精神疾病复发率和因精神疾病退学、休学,保障大学生精神疾病患者接受教育的权利。 相似文献