Objective To examine the prevalence of chikungunya virus in brain tissue samples from rat?like animals in Xiamen, Shenzhen and Guangzhou, and to explore whether the rat?like animals are potential sources of human chikungunya fever infections and the host of the virus. Methods Rat?like animals were trapped in residential areas, city parks, hospitals, markets and schools in Xiamen, Shenzhen and Guangzhou (Yuexiu and Baiyun districts) between January 2013 and June 2016. Brain tissue samples of the trapped animals were collected under sterile. Chikungunya virus was detected by using reverse transcription polymerase chain reaction (RT?PCR). Results Totally 1092 rat?like animals were trapped, which belonged to 7 species, 3 genera, 2 families, 2 orders. Rattus norvegicus was the dominant species in the indoor environment, Rattus losea was dominant in wild environment, and 1092 brain tissue samples were collected. No detectable chikungunya virus was found in the brain tissue samples by RT?PCR. Conclusion There is a low possibility that rat?like animals act infectious sources of human chikungunya fever infections and the host of the virus.

Objective To investigate the distribution of cell membrane tension in a gradient fluid shear stress(FSS)field.Methods A gradient plate flow chamber model was constructed.Fluid-solid coupling numerical simulations were conducted to analyze the distribution of membrane tension with different FSS gradients and FSS amplitudes under varying hydrostatic pressures.Results With an increase in the flow rate at the inlet of the flow chamber,the FSS gradient exhibited a proportionally positive increase.Under the gradient FSS field,the cell membrane tension initially decreased and then increased from the bottom to the top of the cell.Under normal blood pressure,higher hydrostatic pressure was correlated with increased membrane tension.Larger FSS amplitudes result ed in higher membrane tension.When the FSS amplitude was constant,the average difference in membrane tension between the high-and low-FSS regions increased with the FSS gradient.Similarly,with a constant FSS gradient,the average difference in membrane tension between the high-and low-FSS regions increased with the FSS amplitude.Conclusions Local variation in cell membrane tension induced by gradient FSS is a crucial factor influencing the directional migration of osteoclast precursors in a gradient FSS field.

Objective:To explore the relationship between hemoglobin variability (Hb-var) and risk of all-cause death and cardiovascular death in patients with peritoneal dialysis (PD), and to provide basis for reducing the risk of death in PD patients.Methods:It was a multicenter retrospective cohort study. The clinical data of regular PD patients from Nanfang Hospital of Southern Medical University, Shunde Hospital of Southern Medical University, Foshan First People's Hospital and Ganzhou People's Hospital from July 1, 2008 to December 31, 2019 were collected. Hb-var was calculated based on hemoglobin at baseline before PD and in the first year after PD. The patients were divided into low Hb-var group, moderate Hb-var group and high Hb-var group according to the tertiles of first year Hb-var, and the differences of baseline clinical data among three groups were compared. Follow-up endpoints included death, transfer to hemodialysis, transfer to kidney transplantation, transfer to other centers, loss of follow-up, or on December 31, 2021. Cox regression analysis model was used to analyze the association of the first-year Hb-var with all-cause death and cardiovascular death. Fine-Gray competitive risk regression model was used to evaluate the impact of competitive events on mortality risk.Results:A total of 1 562 patients with PD were included in the study, aged (47.6±13.8) years old, with 821 males (52.6%) and baseline hemoglobin of 81 (69, 94) g/L. Hb-var in the first year of PD was 26.6 (16.7, 40.3) g/L. There were statistically significant differences in age, body mass index, serum albumin, hemoglobin, serum creatinine, serum calcium, serum phosphorus, intact parathyroid hormone and the proportion of renin-angiotensin system inhibitors among low Hb-var group (<20.0 g/L), moderate Hb-var group (20.0-35.5 g/L) and high Hb-var group (≥35.5 g/L, all P<0.05). The follow-up time was 33 (19, 51) months, and 208 patients (13.3%) died, among which 111 patients (53.4%) died of cardiovascular death. Multivariate Cox regression analysis showed that the higher Hb-var in the first year, the lower the risk of all-cause death ( HR=0.98, 95% CI 0.97-0.99, P=0.018) and cardiovascular death ( HR=0.98, 95% CI 0.97-0.99, P=0.041) in PD patients. Compared with low Hb-var group, the risk of all-cause death ( HR=0.56, 95% CI 0.37-0.82, P=0.003) and cardiovascular death ( HR=0.54, 95% CI 0.31-0.95, P=0.032) was lowest in the high Hb-var group. The competitive risk regression model analysis showed that Hb-var in the first year was still negatively correlated with the risk of all-cause death ( HR=0.98, 95% CI 0.97-0.99, P=0.041) and cardiovascular death ( HR=0.98, 95% CI 0.97-0.99, P=0.039). Conclusion:High Hb-var in the first year is associated with low risk of all-cause death and cardiovascular death in PD patients with severe anemia at baseline.

Objective:To accurately ascertain the whole genome sequencing and the composition of open reading frames (ORFs) of non-replicating Tiantan strain of vaccinia virus (NTV) using next-generation long-read sequencing technology.Methods:NTV, obtained from our laboratory stock, was amplified and purified on chicken embryo fibroblast cells(CEFs), and the full-length genomic nucleic acid of NTV was extracted. The PacBio HiFi sequencing platform was utilized for de novo assembly to obtain the complete genomic sequence of NTV. Using a homology annotation strategy, we identified its ORF composition and compared it with known non-replicating vaccinia virus strains. Results:The total length of NTV′s genome was 171 729 bp, with a GC content of 33%. Its unique inverted terminal repeat (ITR) region comprised hairpin structures, two tandem repeat regions, and three non-repeat regions. NTV contained 166 ORFs, with major differences observed in the ITR and its surrounding regions when compared to MVA-BN and NYVAC. These three strains shared a common set of 138 ORFs. NTV encoded six unique ORFs related to virus evasion of host antiviral response.Conclusions:This study accurately determines the whole genome sequencing and ORFs composition of NTV, and reveals its similarities and differences with other replication-deficient vaccinia virus strains, which pave a way for the development and application of the next generation of monkeypox vaccines and novel viral vectors.