OBJECTIVE: High-altitude hypoxia exposure often damages hippocampus-dependent learning and memory. Nogo-A is an important axonal growth inhibitory factor. However, its function in high-altitude hypoxia and its mechanism of action remain unclear. METHODS: In an in vivo study, a low-pressure oxygen chamber was used to simulate high-altitude hypoxia, and genetic or pharmacological intervention was used to block the Nogo-A/NgR1 signaling pathway. Contextual fear conditioning and Morris water maze behavioral tests were used to assess learning and memory in rats, and synaptic damage in the hippocampus and changes in oxidative stress levels were observed. In vitro, SH-SY5Y cells were used to assess oxidative stress and mitochondrial function with or without Nogo-A knockdown in Oxygen Glucose-Deprivation/Reperfusion (OGD/R) models. RESULTS: Exposure to acute high-altitude hypoxia for 3 or 7 days impaired learning and memory in rats, triggered oxidative stress in the hippocampal tissue, and reduced the dendritic spine density of hippocampal neurons. Blocking the Nogo-A/NgR1 pathway ameliorated oxidative stress, synaptic damage, and the learning and memory impairment induced by high-altitude exposure. CONCLUSION: Our results demonstrate the detrimental role of Nogo-A protein in mediating learning and memory impairment under high-altitude hypoxia and suggest the potential of the Nogo-A/NgR1 signaling pathway as a crucial therapeutic target for alleviating learning and memory dysfunction induced by high-altitude exposure. GRAPHICAL ABSTRACT available in www.besjournal.com.
Animals ; Oxidative Stress ; Hippocampus/metabolism* ; Rats ; Nogo Proteins/genetics* ; Male ; Rats, Sprague-Dawley ; Hypoxia/metabolism* ; Altitude ; Synapses ; Humans ; Altitude Sickness/metabolism*

Chronic kidney disease (CKD) has become a significant global public health problem. It is defined as chronic renal structural and functional dysfunction caused by various reasons. The prevalence of obesity and diabetes has increased dramatically in developing countries, which substantially affected the patterns of CKD observed in these regions. It’s inevitable that the disease spectrum of CKD is converting to metabolic diseases. CKD is also considered an independent risk factor for renal aging and cardiovascular disease in the elderly, which usually progresses to end-stage renal disease (ESRD). Renal interstitial fibrosis is the pathological basis of ESRD and is a microscopic manifestation of renal aging. Conversely, renal aging is a risk factor for interstitial fibrosis. Although the healthy kidney has a relatively low lipid level, CKD-associated dyslipidemia has been extensively studied. Nevertheless, less is known about the contribution of lipid disorders to the development of renal senescence and interstitial fibrosis. Recent studies have demonstrated that lipid metabolism disorders occur in the progress of renal aging and interstitial fibrosis. Renal lipids accumulate once lipid uptake and synthesis exceed the balance with lipolysis, which is mainly characterized by increased levels of triglyceride (TG) and oxidized low-density lipoprotein, and decreased levels of high-density lipoprotein. Excessive lipid accumulation in the kidney not only induces lipotoxicity and endoplasmic reticulum stress but also increases intracellular and mitochondrial reactive oxygen species, which induce stress injury and senescence in renal tubular epithelial cells. Pro-inflammatory and pro-fibrotic cytokines in a senescence-associated secretory phenotype secreted by senescent renal tubular epithelial cells further accelerate their senescence as well as the occurrence of inflammation and pericyte loss, promoting secretion of extracellular matrix (ECM) and subsequent fibrosis in the tubulointerstitial compartment. In addition, podocyte hypertrophy also leads to glomerulosclerosis. Currently, most of the studies on inhibiting or even reversing renal interstitial fibrosis are still in the experimental stage. What’s more, effective drugs to slow down renal aging have not been reported. Many inflammatory and fibrotic factors are both components of the senescence-associated secretory phenotype (SASP), nevertheless, they are not sufficient to recognize cellular senescence. Given that indicators of senescence may vary from disease to disease and organ to organ, there is a need for more sensitive and specific senescence assays. Crucial enzymes and regulatory proteins of lipid metabolic pathways are expected to be potential targets for ameliorating renal aging and interstitial fibrosis. Lipid-lowering approach might represent another therapeutic in the management of kidney injury associated with metabolic dysfunction. Thus, clarifying the molecular regulatory mechanisms of lipid metabolism in kidney is extremely important for the delay of renal aging and the treatment of interstitial fibrosis. This review outlines the effects of lipid metabolism disorders on renal aging and renal fibrosis, analyses the role of lipid metabolism disorders in the development of renal diseases, and summarizes the potential targets and strategies for the prevention of renal aging and renal fibrosis based on lipid metabolism regulation, which will provide a reference for the discovery of new targets for the treatment of renal fibrosis.

Objective To investigate the infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93％and a HCV positive rate of 0.54％.The positive rate of HCV in male and female patients were 0.60％and 0.48％,respectively,with a statistically sig-nificant difference(x2=47.18,P＜0.001).The HCV positive rate in the 50-＜60 age group was the highest(0.76％),followed by the 40-＜50 age group(0.71％).Difference among all age groups was statistically signifi-cant(x2=696.74,P＜0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57％;775 patients were infected with HCV,with a positive rate of 2.21％.In 2020,HCV positive rates in hospitals of different scales were 0.46％-0.63％,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P＜0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19％-0.81％,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06％-0.82％,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95％and 3.48％,respectively.Followed by departments of orthopedics(7.72％),gastroenterology(3.77％),nephrology(3.57％)and general intensive care unit(ICU,3.10％)in 2003,as well as departments of gastroenterology(1.35％),nephrology(1.18％),endocrinology(0.91％),and general intensive care unit(ICU,0.79％)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.

Osteonecrosis of the femoral head(ONFH)is a common orthopedic disease,and hip preservation surgery has high clinical value in the early stages of ONFH,especially for young and middle-aged patients.However,the repair of ONFH is heterogeneous,leading to inter-individual variations in the efficacy of hip preservation.Currently,the existing tissue-engineered scaffolds in the field of hip preservation are uncontrollable after implantation,making it difficult to achieve precise repair.Smart responsive materials have good biocompatibility and self-feedback capability.By combining them with therapeutic drugs to construct stimulus-responsive drug delivery systems,new possibilities are provided for the precise repair of ONFH.This paper reviews the research progress of smart responsive materials at home and abroad.Based on the response principles of various materials and the repair characteristics of ONFH,the application prospects of various smart responsive materials such as reactive oxygen species-responsive,fluid shear stress-responsive,and light/magnetic-responsive materials are discussed and prospected in the field of precise repair for ONFH,providing new ideas for the precise treatment of ONFH.

Objective To establish an acute exposure model of extreme plateau hypobaric hypoxia environment and explore transcriptomic changes related to learning and memory impairment in rats.Methods Healthy male SD rats aged 6-weeks,200-250 g,were selected and divided into control group and plateau group.The control group was treated with normal pressure and oxygen(19 rats),and the plateau group was placed in a hypobaric hypoxia chamber(19 rats)at a simulated altitude of 8000 meters and treated for 72 hours.Behavioral changes were detected with 16 animals from each group using contextual fear conditioning and Morris water maze(8 rats each).Three hippocampal tissues were extracted from each group for transcriptomic sequencing,and the molecular mechanism of learning and memory impairment induced by extreme plateau environment was analyzed by Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG)and gene set enrichment analysis(GSEA)enrichment.Results The behavioral result showed that compared with the control group,the fear memory and spatial learning memory abilities of rats in plateau group were decreased.GO and KEGG analyses showed that the extreme altitude environment reshaped the hippocampal microenvironment and affected the intercellular signal transmission,while GSEA analysis showed that the extreme altitude environment up-regulated the gene set related to the plasma membrane and extracellular matrix.Conclusion The extreme plateau environment at an altitude of 8000 meters could affect the microenvironment of rat hippocampus,destroy intercellular connections and impair intercellular communication and then induce learning and memory impairment.

The purpose of this study was to identify the tick species native to Xindi Township,Yumin County,Xinjiang,China.Preliminary morphological identification of parasitic ticks collected from animals in the area was conducted with an ultra-depth of field three-dimensional VHX 600 digital stereo microscope.Total DNA of the ticks was extracted,amplified by PCR based on the COI and ITS2 gene loci,and the posi-tive PCR products were sequenced.The sequence were a-ligned with reference sequences from the NCBI database were aligned with the Basic Local Alignment Search Tool.A genet-ic phylogenetic tree was generated with the neighbor-joining method of MEGA 7.0 software to determine the evolutionary biological characteristics of ticks.Morphological identification showed that the ticks collected from Xindi Township of Yu-min County were consistent with the characteristics of Hya-lomma asiaticum.An evolutionary tree based on the COI and ITS2 gene sequences showed that the ticks collected in this study were clustered with known H.asiaticum sequences.The PCR products of COI and ITS2 were sequenced and compared,which confirmed that the collected tick species were H.asiaticum,in agreement with the morphological and molecular biological results.These findings help to clarify the distribution of ticks in Xindi Township of Xinjiang,and provide basic data for the analysis of tick genetic and evolutionary characteristics,as reference for surveillance and control of ticks in the Xinjiang Uygur Autonomous Region.

Objective:To investigate the influence of using tourniquet on the postoperative pain,the muscle injury,the meniscal healing and the rehabilitation of meniscus function after surgery of meniscus suture and repair under arthroscopy.Methods:A total of 144 patients who underwent surgery of suture and repair for meniscus of knee joint in hospital were selected and they were divided into tourniquet group(81 cases)and non-tourniquet group(63 cases)according to whether used tourniquet.Postoperative muscle injury was assessed according to postoperative serum creatine kinase(CK),and postoperative pain was assessed by using visual analogue scale(VAS).The international k nee documentation committee(IKDC)scoring system,Lysholm knee joint score and Tegner knee joint score system were used to assess the rehabilitation effect of the function of knee joint of patient after surgery,and the clinical healing after the surgery of meniscus suture was evaluated according to Barrett standard.Results:There were no significant differences in CK levels between the two groups before surgery,2 days and 8 days after surgery,and at the last follow-up(t=1.667,t=-2.143,t=-4.461,t=-6.380,P>0.05),respectively.There were no significant differences in VAS scores between the two groups before surgery,2 days and 8 days after surgery,and at the last follow-up(Z=-1.121,Z=-1.364,Z=0.745,Z=-0.894,P>0.05),respectively.There were no significant differences in IKDC scores and Lysholm scores before and after surgery between the two groups(tIKDC=-1.680,t=0.533,tLysholm=-3.162,t=-2.543,P>0.05),respectively.There were no significant differences in Tegner score before and after operation between the two groups(Z=-0.803,Z=-0.370,P>0.05),respectively.There was no significant difference in the healing rate of meniscus after surgery between the two groups(Z=-0.247,P>0.05).Conclusion:The use of tourniquet in the surgery of meniscus suture under arthroscopy would not cause muscle injury,and would not aggravate pain,and does not affect healing rate and rehabilitation of meniscus function of patients.

Aim To investigate the antibacterial activity and anti-resistant mutation ability of Qiguiyin decoction (a traditional Chinese herbal formula) combined with levofloxacin against pseudomonas aeruginosa byantibacterial experiment in vitro and serum pharmacology. Methods The minimal inhibitory concentrations (MICs) of levofloxacin and Qiguiyin decoction were detected respectively by the broth dilution technique.The MIC of the combination of two drugs was determined by the micro chessboard dilution method. The effects of combined drugs on enhancing the antibacterial activity of different strains were evaluated respectively by calculating the fractional inhibitory concentration index (FICI). The drug-containing serum of levofloxa-cin group, Qiguiyin decoction group, Qiguiyin decoction combined with levofloxacin group and control group was prepared. The antibacterial rate, MIC and MBC of 10% ~ 90% serum against the two strains were determined. Results Combined with Qiguiyin decoction, MIC of levofloxacin against pseudomonas aeruginosa (standard/resistant) decreased significantly, 0. 5 < FICI ^ 1. With the increase of the proportion of serum, the inhibitory rate of 10% ~ 90% drug-containing serum to pseudomonas aeruginosa (standard/resistant) increased gradually.compared with the control group, the inhibitory effect of the Qiguiyin group on bacteria was significantly enhanced. The MIC

Objective The traditional round incision or cross incision brain harvesting method can not meet the requirements of protecting the donor's remains. In this study, the method of brain removal through a posterior incision on the scalp of both ears was proposed, which effectively protected the donor's remains. Methods Adopting the incision 2. 0 cm above the external occipital protuberance to the most front edge of the auricle to obtain a complete brain. Results The incision did not involve the head and face skin, which was small and conducive to suture repair and reduce exudation. Conclusion The incision effectively protects the donor' s remains, and it will be conducive to the establishment and development of the brain bank.

OBJECTIVES: To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia. METHODS: A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively. RESULTS: Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia. CONCLUSIONS The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia.
Infant, Newborn ; Humans ; Male ; Pregnancy ; Female ; Nomograms ; Retrospective Studies ; Cesarean Section ; Risk Factors ; Asphyxia Neonatorum/etiology*