Investigation of the active ingredients and mechanism of Shuangling extract in dextran sulfate sodium salt induced ulcerative colitis mice based on network pharmacology and experimental verification.

OBJECTIVE: To explore the pharmacodynamic effects and potential mechanisms of Shuangling extract against ulcerative colitis (UC). METHODS: The bioinformatics method was used to predict the active ingredients and action targets of Shuangling extract against UC in mice. And the biological experiments such as serum biochemical indexes and histopathological staining were used to verify the pharmacological effect and mechanism of Shuangling extract against UC in mice. RESULTS: The Shuangling extract reduced the levels of seruminterleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-N), interleukin-6 (IL-6) and other inflammatory factors in UC mice and inhibited the inflammatory response. AKT Serine/threonine Kinase 1 and IL-6 may be the main targets of the anti-UC action of Shuangling extract, and the TNF signaling pathway, Forkhead box O signaling pathway and T-cell receptor signaling pathway may be the main signaling pathways. CONCLUSION: The Shuangling extract could inhibit the inflammatory response induced by UC and regulate intestinal immune function through multiple targets and multiple channels, which provided a new option and theoretical basis for anti-UC.

Research progress on the effect of panretinal photocoagulation on visual field in the treatment of diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

The early change in the visual field in diabetic retinopathy(DR)are often more timely than visual acuity. However, panretinal photocoagulation(PRP)treatment for DR not only delays the progression of the disease, but also causes adverse side effects such as loss of vision and visual field in the affected eye. Studies have shown that patients with DR after PRP treatment may fail a driving test due to visual field defect within a central range of 20°. In order to ensure the efficacy of PRP and achieve the purpose of reducing complications, laser technology has been continuously improved and developed. By adjusting laser parameters, utilizing new laser systems, combining with anti-vascular endothelial growth factor(VEGF)drugs, and integrating traditional Chinese and Western medicine, the visual field in the affected eye can be improved to a certain extent, leading to better treatment outcome. In the future, the degree of retinal ishemia should be quantitatively assessed using the ischemic index(ISI), and the optimal threshold and photocoagulation range of PRP treatment recommendations should be explored based on the ISI index and the distribution of retinal non-perfusion area, so as to provide a more timely and reasonable personalized treatment plan for DR patients. This article briefly reviews the effect of PRP on the visual field in the treatment of DR.

Establishment and applicability comparison of four models of acute liver ischemia/reperfusion injury in rat / 中华危重病急救医学

OBJECTIVE@#To clarify the preparation methods of four rat models of liver ischemia/reperfusion injury (IRI) and to determine a liver IRI animal model that is consistent with clinical conditions, has stable pathological and physiological injury, and is easy to operate.@*METHODS@#A total of 160 male Sprague-Dawley (SD) rats were randomly divided into four groups using an interval grouping method: 70% IRI (group A), 100% IRI (group B), 70% IRI with 30% hepatectomy (group C), and 100% IRI with 30% hepatectomy (group D), with 40 rats in each group. Each model was further divided into sham operation group (S group) and ischemia groups of 30, 60, and 90 minutes, with 10 rats in each group. After surgery, the survival status and awakening time of the rats were observed, and the liver lobectomy weight, bleeding volume, and hemostasis time of groups C and D were recorded. Blood samples were collected by cardiac puncture after 6 hours of reperfusion for determination the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), serum creatinine (SCr), and γ-glutamyl transpeptidase (γ-GT) in the serum to assess liver and kidney function. Hematoxylin-eosin (HE) staining and immunohistochemical staining of macrophages were performed to analyze the liver tissue structure damage from a pathological perspective.@*RESULTS@#Rats in group A exhibited earlier awakening and acceptable mental status, while rats in the other groups showed delayed awakening and poor mental status. The hemostasis time in group D was approximately 1 second longer than that in group C. The mortality of rats subjected to 60 minutes of 70% hepatic ischemia was 0. Compared to the sham operation group, rats in each experimental group showed significant increases in serum levels of AST, ALT, ALP, BUN, SCr, and γ-GT, indicating impaired liver and kidney function in the rat models of liver IRI. In groups A, B, and C, the 90-minute ischemia subgroup exhibited more pronounced elevation in AST, ALT, ALP, BUN, SCr, and γ-GT levels compared to the 30-minute ischemia subgroup [AST (U/L): group A, 834.94±56.73 vs. 258.74±18.33; group B, 547.63±217.40 vs. 277.67±57.92; group C, 930.38±75.48 vs. 640.51±194.20; ALT (U/L): group A, 346.78±25.47 vs. 156.58±13.25; group B, 408.40±138.25 vs. 196.80±58.60; group C, 596.41±193.32 vs. 173.76±72.43; ALP (U/L): group A, 431.21±34.30 vs. 315.95±15.64; group B, 525.88±62.13 vs. 215.63±17.31; group C, 487.53±112.37 vs. 272.46±92.33; BUN (U/L): group A, 18.35±5.63 vs. 14.32±2.30; group B, 30.21±4.55 vs. 17.41±8.14; group C, 20.50±3.64 vs. 15.93±3.22; SCr (U/L): group A, 27.47±8.91 vs. 22.37±5.66; group B, 43.60±15.57 vs. 36.80±7.95; group C, 63.81±20.24 vs. 42.47±7.03; γ-GT (U/L): group A, 15.64±3.57 vs. 6.82±1.48; group B, 9.28±1.91 vs. 5.62±1.21; group C, 10.98±3.18 vs. 5.67±1.10; all P < 0.05]. The 100% IRI 90-minute group and 100% IRI 90-minute group with 30% hepatectomy exhibited more pronounced increases in the above-mentioned indicators compared to the corresponding 70% IRI control group, indicating increased liver and kidney damage in rats subjected to combined blood flow occlusion and hepatectomy. HE staining showed clear liver tissue structure with intact and orderly arranged cells in the sham operation group, while the experimental groups exhibited cell structure damage, including cell rupture or collapse, cell swelling, nuclear pyknosis, deep cytoplasm staining, cell shedding, and necrosis. The interstitium showed infiltration of inflammatory cells. Immunohistochemical staining revealed a higher number of macrophages in the experimental groups compared to the sham operation group.@*CONCLUSIONS@#Four models of liver IRI in rat were successfully established. As the duration and severity of hepatic ischemia increased, liver cell ischemia worsened, leading to increased hepatocellular necrosis and exhibiting characteristic features of liver IRI. These models can effectively simulate liver IRI following liver trauma, with the group subjected to 100% ischemia and 30% hepatectomy showing the most severe liver injury. The designed models are reasonable, easy to perform, and exhibit good reproducibility. They can be used for investigating the mechanisms, therapeutic efficacy, and diagnostic methods related to clinical liver IRI.

The effects of fixation methods on early postoperative weight bearing in elderly patients with femoral intertrochanteric fractures / 中华创伤骨科杂志

With rapid aging of populations, the incidence of intertrochanteric fractures in the elderly is increasing. Surgery is the preferred treatment for the fractures. The internal fixation methods commonly used for the fractures in clinical practice include dynamic hip screw (DHS), proximal femoral nail antirotation (PFNA), Gamma nail, InterTan intramedullary nail, and proximal femoral bionic nail (PFBN) which stemmed from the "lever reconstruction balance" theory. However, there has been no unified theoretical guidance on the early weight-bearing time for affected limbs after different internal fixation methods. This article reviews the current situation of early weight-bearing in elderly patients with femoral intertrochanteric fracture after treatment with different internal fixations, with a view to providing references for clinical healthcare professionals.

Dissecting lncRNA-mRNA competitive regulatory network in human islet tissue exosomes of a type 1 diabetes model reveals exosome miRNA markers.

Background: Emerging evidence shows that exosomes play a crucial role in the occurrence and development of diabetes and its complications. The molecules in exosomes can be regarded as important markers for the diagnosis of diseases. However, it is presently unclear the pathological association mechanism between exosomes and diabetes. Results: In this study, transcriptome data and lncRNA regulatory association data of human pancreatic islet-derived exosome were integrated to construct the ceRNA network. Network analysis revealed that lncRNA with differential expression were primarily involved in islet insulin secretion signaling pathways, including Hippo, TGF-beta, Wnt, FOXO, Neurotrophin and ErbB signaling pathway. Further, combined with miRNA mediated competitive regulation and differential expression analysis results, potential markers of diabetes were revealed and validated in independent datasets. Finally, we analyzed the mechanisms of diabetes based on the competitive regulatory association and function of lncRNA. Conclusion: Our results suggest that lncRNA such as lncRNA PVT1, LINC00960 and hsa-miR-107 might be involved in inflammation response in T1DM, and the former lncRNA chose in the present study may serve as novel biomarkers and potential targets for the diagnosis and treatment of T1DM.

Reason for failed fixation with dynamic hip screws for intertrochanteric fracture: analysis based on the lever-balance-reconstruction theory / 中华创伤骨科杂志

Objective:To study the reason for failed fixation with dynamic hip screws (DHS) and the indications for DHS fixation in the treatment of intertrochanteric fracture based on the lever-balance-reconstruction theory.Methods:A retrospective analysis was performed of the data of 32 patients with intertrochanteric fracture who had been treated by DHS fixation at Department of Orthopaedic Trauma, Peking University People's Hospital from January 1999 to December 2019. There were 22 males and 10 females, aged from 34 to 91 years (average, 67.7 years). By the AO classification, 15 fractures were type 31-A1, 13 ones type 31-A2, and 4 ones type 31-A3. According to the lever-balance-reconstruction theory, after the position of postoperative fulcrum was determined depending on the relationship between fracture line and internal fixation, the medial and lateral force arms were measured after internal fixation. The 32 patients were divided into 2 groups according to the position of fulcrum after internal fixation. In group A of 13 patients, the fulcrum was located in or within the center of the medullary cavity; in group B of 19 patients, the fulcrum was located outside the center of the medullary cavity. The incidence of internal fixation failure was compared between the 2 groups.Results:Internal fixation failure occurred in 15 of the 32 patients: cutting out of the head and neck screws without penetration in 2 cases, screw withdrawal in 8 cases, hip varus deformity in 10 cases, and femoral neck shortening in 15 cases. The 2 groups were comparable because there were no statistically significant differences in their preoperative general data or types of internal fixation between them except AO classification ( P>0.05). The length of medial force arm (power arm) averaged 51.12 mm (from 39.4 to 57.9 mm) and the length of lateral force arm (resistance arm) 23.37 mm (from 15.1 to 31.0 mm) in group A where 3 patients experienced internal fixation failure after operation; the length of medial force arm (power arm) averaged 63.71 mm (from 52.3 to 74.5 mm) and the length of lateral force arm (resistance arm) 9.94 mm (from 3.1 to 18.3 mm) in group B where 12 patients experienced internal fixation failure after operation. There was a significant difference between the 2 groups in internal fixation failure ( P=0.036). Conclusions:In the DHS fixation of intertrochanteric fracture, the postoperative fixation failure is associated with the fulcrum position after reconstruction. DHS is only indicated for intertrochanteric fractures whose fracture line (post-reconstruction fulcrum) is near and inside the center of the medullary cavity, but not for those whose fracture line (post-reconstruction fulcrum) is outside the medullary cavity.

Surveillance of pathogens of infectious diarrhea among children in Zhengzhou City / 预防医学

Objective@#To analyze the pathogenic spectrum of infectious diarrhea among children in Zhengzhou City in 2020, so as to provide insights into the management of childhood infectious diarrhea.@*Methods@#A total of 230 stool samples were collected from children with diarrhea in the Diarrhea Clinic of Zhengzhou Municipal Children's Hospital in 2020. Diarrheagenic Escherichia coli, Salmonella, Shigella, Vibrio parahaemolyticus, Campylobacter and Aeromonas were isolated. Salmonella was typed using pulsed-field gel electrophoresis ( PFGE ) and antimicrobial resistance was tested in Salmonella. The main types and drug resistance of pathogens were descriptively analyzed.@*Results@#The 230 children with diarrhea included 152 males and 78 females, with a male to female ratio of 1.95∶1. There were 173 cases at ages of 3 years and below ( 75.22% ), and 82 cases seen between June and August ( 35.65% ). A total of 71 pathogenic bacteria strains were isolated, with a detection rate of 30.87%. Salmonella was the most frequently isolated pathogen ( 35 strains, 15.22% prevalence ), following by diarrheagenic E. coli ( 20 strains, 8.70% ). Eleven serotypes of Salmonella were identified, which mainly included S. enteritidis and S. typhimurium. PFGE typing revealed 25 band patterns of Salmonella, with a similarity ranging from 11.85% to 100%. Salmonella were sensitive to imipenem, meropenem, polymyxin B and amikacin and highly resistant to streptomycin ( 85.71% ), ampicillin ( 80.00% ) and sulfaisoxazole ( 80.00% ). A 82.86% proportion of multi-drug resistance was detected in the 29 Salmonella strains. @*Conclusions@# A wide range of pathogenic bacteria were detected from the childhood infectious diarrhea in Zhengzhou City in 2020, which mainly included Salmonella and diarrheagenic E. coli. A high polymorphism level was seen in PFGE fingerprints of Salmonella, which presented high-level resistance to antimicrobial agents.

Analysis of the status quo and influencing factors of personal control in patients with ischemic stroke / 中风与神经疾病杂志

@#Objective　To investigate the current status of personal control in patients with ischemic stroke（IS） and to analyze its influencing factors.Methods　The convenience sampling method was used to select 180 IS patients who met the inclusion criteria as the research objects.It conducts a questionnaire survey.Results　IS patients had PMS score (17.96±1.96),GSES score (18.47±2.09),and AODS total score (74.21±4.22).Multiple linear regression analysis showed that the level of education,the number of dysfunctions,the NIHSS score,and the general Efficacy and disability acceptance were the influencing factors of personal control (P<0.05).Conclusion　The level of personal control of IS patients is low,and there are many influencing factors.Medical staff should guide patients to establish confidence in the face of the disease and improve disease cognition,so as to promote the level of personal control.

Study on the Cognitive Status Quo of “Prohibiting“”Avoiding“”Using Caution ”in the Clinical Application of TCM / 中国药房

OBJECTIVE：To understand the current status of clinical understanding of “prohibiting”“avoiding”“using caution ” in the application of TCM ，and to provide reference for standardizing the connotation and rational application of “prohibiting” “avoiding”“using caution ”of TCM. METHODS ：Based on the theory of “knowledge-attitude-behavior”，doctor-pharmacist questionnaires and patient questionnaires were designed on the basis of literature research and clinical practice. Through the “Tencent questionnaire ”platform，800 doctor-pharmacist questionnaires were distributed to nearly 300 medical institutions from 32 provinces（cities，autonomous regions ）and 800 patient questionnaires were distributed to public patiants who had used TCM nationwide by anonymous online method. After dimensionality reduction of the questionnaire from three dimensions of cognition ， attention and behavior ，the cognition ，attention and behavior of “prohibiting”“avoiding”“using caution ”in the application of TCM were evaluated by 10 points system. RESULTS ：A total of 703 doctor-pharmacist questionnaires were collected ，including 638 valid questionnaires with recovery rate of 87.9％ and effective rate of 90.8％；Cronbach alpha coefficient was 0.90. A total of 644 patient questionnaires were collected ，including 621 valid questionnaires with recovery rate of 80.5％ and effective rate of 96.4％ . The cognition score of doctors and pharmacists to the terms of “prohibiting”“avoiding”“using caution ”in clinical application of TCM was （7.94±1.21），and that of patients was （5.64±1.54）. The score of doctors and pharmacists ’attention to the above terms was （9.47±1.15）（Spearman Rho correlation coefficient with cognition score was 0.077，P＞0.05），and the score of behavioral ability of patients was （7.01±1.71）（Spearman Rho correlation coefficient with cognition score was －0.021，P＞ 0.05）. The score of behavior ability was （7.43 ± 1.72） （Spearman Rho correlation coefficient with cognition score was 0.233，P＜0.01）. TCM textbooks （89.2％），trainingmeetings （66.5％） and herbal prescriptions （58.2％） were the main ways for doctors and pharmacists to learn the above taboos. Medical staff （74.2％）and internet （52.5％）were the main ways for patients to understand the above taboos. CONCLUSIONS ：Doctors，pharmacists and patients pay more attention to the terms of “prohibiting”“avoiding”“using caution ”in the clinical application of TCM ，but their cognition and executive power were low. Clinical cognition of “prohibiting”“avoiding”“using caution ”in the application of TCM is relatively vague，and the corresponding clinical practice behavior is lacking. It is yet to establish clinical specialist consensus in the field of TCM and publicize it actively to improve the level of clinical rational drug use.

Determination of β-lactoglobulin in Anti-HPV Biological Protein Dressing by Amino Acid Assay / 中国医疗器械杂志

OBJECTIVE@#To establish an amino acid assay for the determination of β-lactoglobulin in Anti-HPV biological protein dressing.@*METHODS@#Under acidic conditions, β-lactoglobulin is hydrolyzed into free amino acids, separated by cation exchange chromatography, and derivatived after ninhydrin column. The chromatogram at 570 nm is collected. The content of β-lactoglobulin in the sample is indirectly determined by measuring the lysine content obtained by hydrolysis.@*RESULTS@#β-lactoglobulin has a good linear relationship in the concentration range of 77.28~309.12 μg/mL (@*CONCLUSIONS@#The method is simple, specific, accurate and reproducible, which is suitable for the quantitative analysis of β-lactoglobulin in anti-HPV biological protein dressing.

Failure analysis in proximal femoral nail antirotation fixation for intertrochanteric fractures / 中华创伤骨科杂志

Objective:To analyze the causes and risk factors for failure of internal fixation with proximal femoral nail antirotation (PFNA) in the treatment of femoral intertrochanteric fractures.Methods:A retrospective analysis was conducted of the 568 patients with femoral intertrochanteric fracture who had been treated with PFNA fixation at Department of Orthopaedic Surgery, The Fifth Central Hospital of Tianjin from March 2013 to March 2018. They were 348 males and 220 females, aged from 44 to 93 years (average, 74.6 years). According to the fracture stability classification, the patients were divided into a stable group of 424 cases and an unstable group of 144 cases. According to the AO classification, the stable group had type 31-A1 and type 31-A2.1 while the unstable group type 31-A2.2, type 31-A2.3 and type 31-A3. The 2 groups were compared in terms of reduction quality, rate of internal fixation failure, and function of the affected hip. Single factor and multi-factor binary logistic regression analyses were conducted to determine the risk factors responsible for failure of PFNA fixation of femoral intertrochanteric fracture.Results:There were no significant differences in the preoperative general data between the 2 groups, showing comparability between groups ( P> 0.05). Internal fixation failure occurred in 19 cases, which was caused by spiral blade withdrawal in 13 cases, femoral neck shortening in 17 cases, hip varus in 14 cases, and spiral blade cut-out in 14 cases. The failure rate for the stable group was 1.2% (5/424), significantly lower than that for the unstable group [9.7%,(14/144)] ( P<0.05). The Harris hip score at the last follow-up for the stable group [98(95,100)] was significantly higher than that for the unstable group [84 (82, 87)] ( P<0.05). There was no significant difference in reduction quality between the 2 groups ( P>0.05). The multivariate analysis showed that osteoporosis ( OR=7.283, 95% CI: 1.626 to 32.623, P=0.009) and unstable fracture ( OR=11.607, 95% CI: 4.039 to 33.355, P<0.001) were risk factors responsible for the failure of PFNA fixation of femoral intertrochanteric fracture. Conclusions:PFNA fixation for unstable intertrochanteric fracture can lead to a high failure rate. It forms a lever like structure so that the main stress is shifted to the internal fixation. Its lever fulcrum is located at the angle of intramedullary fixation so that a long arm forms at the load-bearing side, leading to a high failure rate. The weight-free time should be longer for patients with osteoporosis and unstable fracture after operation.

Analysis of characteristics and causes of postoperative invalid fixation failures of femoral intertrochanteric fractures / 中华创伤杂志

Objective:To investigate the characteristics of postoperative internal fixation failures of femoral intertrochanteric fractures and analyze the related reasons using the leverage-balance-reconstruction theory.Methods:A retrospective case series study was performed for 40 patients suffering from implant failure after internal fixation of femoral intertrochanteric fractures admitted to Peking University People's Hospital from January 1999 to December 2019. There were 20 males and 20 females, aged from 43 to 92 years [(74.1±11.5)years]. The patients were assigned to extramedullary fixation (extramedullary fixation group, 17 patients) and intramedullary fixation (intramedullary fixation group, 23 patients). Complications associated with internal fixation were recorded, including internal fixation cutout, coxa vara deformity of hip joint, internal fixation withdrawal, femoral heck shortening and internal fixation breakage. Based on the lever-balance-reconstruction theory, the failure reasons of internal fixation were analyzed in combination with the change of arm length and outward shift of fulcrum measured before operation, after internal fixation and after fixation failure.Results:Among 40 patients, internal fixation cutout occurred in 18 patients, coxa vara deformity of hip joint in 37, internal fixation withdrawal in 29, femoral neck shortening in 37 and internal fixation breakage in 3. In extramedullary fixation group, the lengths of primary power arm and resistance arm were (8.0±1.0)mm and (59.4±10.9)mm, the lengths of power arm and resistance arm after fixation were (72.7±21.7)mm and (8.9±7.4)mm, the lengths of power arm and resistance arm after fixation failure were (50.3±14.9)mm and (33.6±17.6)mm. In intramedullary fixation group, the lengths of primary power arm and resistance arm were (6.7±0.6)mm and (49.8±9.9)mm, the lengths of power arm and resistance arm after fixation were (51.5±7.0)mm and (19.8±5.9)mm, the lengths of power arm and resistance arm after fixation failure were (41.6±9.6)mm and (32.4±7.7)mm. In each group, the lengths of power arm and resistance arm after internal fixation showed significant differences from that of normal ones and from that after fixation failure ( P<0.05). The length of power arm in extramedullary fixation group was larger than that in intramedullary fixation group ( P<0.05). The shortening of power arm in extramedullary fixation group was larger than that in intramedullary fixation group after fixation failure ( P<0.05). Conclusions:The extramedullary and intramedullary fixation of femoral intertrochanteric fractures result in the displacement of reconstruction fulcrum. The shortening of power arm is observed after fixation failure. The leverage-balance-reconstruction theory is helpful to analyze the cause of complications. The power arm after extramedullary fixation is longer than that after intramedullary fixation and is therefore more prone to fixation failure. The primary cause of postoperative internal fixation complications is to achieve a new balance of leverage.

Finite element analysis of biomechanical properties of bionic surface hip prosthesis / 中华骨科杂志

Objective:To compare the biomechanical properties of traditional surface hip prosthesis and bionic surface hip prosthesis.Methods:The Sawbone digital model (#3908, Left, Medium) was selected as the research object. Mimics 21.0 software was used to reconstruct the physical model of femur. Solidworks 16.0 software was used to build the model of prostheses, including the traditional and bionic (type 1-4) protheses and their assembly. The distances from the screw cross position to the top of pressure screw of type 1 to type 4 protheses were 20.22 mm, 30.12 mm, 32.17 mm and 37.76 mm, respectively. The mechanical distribution characteristics of the whole model were measured and the stress distribution cloud map was obtained.Results:The peak stresses at bone-stem junction of traditional prosthesis and type 1-4 hip prostheses were 32.18 MPa, 13.80 MPa, 15.01 MPa, 23.46 MPa and 34.51 MPa, respectively. With the fulcrums away from the top of the femur, the peak stresses at the fulcrums of type 1-4 hip protheses were 37.98 MPa, 48.60 MPa, 54.80 MPa, and 53.87 MPa, respectively. The maximum stress above femoral neck of traditional prosthesis and type 1-4 hip prostheses were 8.00 MPa, 7.80 MPa, 7.04 MPa, 7.03 MPa and 7.51 MPa, respectively. The maximum stresses under femoral neck was 15.38 MPa, 14.20 MPa, 11.11 MPa, 13.10 MPa and 12.18 MPa, respectively. The maximum stresses in the greater trochanter region of femur were 13.08 MPa, 11.61 MPa, 13.09 MPa, 11.02 MPa and 39.51 MPa, respectively.Conclusion:Compared with the traditional surface hip prosthesis, the type I bionic surface hip prosthesis is designed based on the lever balance reconstruction theory. With the bionic reconstruction of the tension trabeculae and compression trabeculae through reasonable screw placement angles and the inward movement of the fulcrum closer to the center of the femoral head, the new type prothesis make up for the design defects of the traditional surface hip prosthesis, optimize the stress distribution in the proximal femur, and improve the stability of the prosthesis after replacement, which help reduce the risk of femoral neck fracture and prosthesis loosening, and extend the service life of the prosthesis.

Genetically-predicted vitamin D status, ambient UVB during the pandemic and COVID-19 risk in UK Biobank: Mendelian Randomisation study

A growing body of evidence shows that poor vitamin D status has been associated with an increased susceptibility to viral and bacterial respiratory infections. In this study, we aimed to examine the association between vitamin D and COVID-19 risk and outcomes, and to explore potential causal effects. We used logistic regression to identify associations between different vitamin D variables (25-hydroxyvitamin D concentration (25-OHD), ambient UVB and genetically-predicted 25-OHD concentrations) and COVID-19 (risk of infection, hospitalisation and death) in 495,780 participants from UK Biobank. We subsequently performed a Mendelian Randomisation (MR) study to test if there was any causal effect. In total, 1,746 COVID-19 cases and 399 COVID-19 deaths occurred between March and June 2020. We found significant inverse associations between COVID-19 infection and 25-OHD in univariable models, but these associations were non-significant after adjustment for confounders. Ambient UVB was strongly and inversely associated with hospitalization and death. Although the main MR analysis showed that genetically-predicted vitamin D levels were not causally associated with COVID-19 risk, MR sensitivity analysis using weighted mode method indicated a potential causal effect (OR=0.72, 95% CI:0.53-0.98; P=0.041). In conclusion, our study found suggestive evidence of association between vitamin D and the risk or severity of COVID-19 but further studies are needed.

Physical activity, BMI and COVID-19: an observational and Mendelian randomisation study

Physical activity (PA) is known to be a protective lifestyle factor against several non-communicable diseases while its impact on infectious diseases, including Coronavirus Disease 2019 (COVID-19) is not as clear. We performed univariate and multivariate logistic regression to identify associations between body mass index (BMI) and both objectively and subjectively measured PA collected prospectively and COVID-19 related outcomes (Overall COVID-19, inpatient COVID-19, outpatient COVID-19, and COVID-19 death) in the UK Biobank (UKBB) cohort. Subsequently, we tested causality by using two-sample Mendelian randomisation (MR) analysis. In the multivariable model, the increased acceleration vector magnitude PA (AMPA) was associated with a decreased probability of overall and outpatient COVID-19. No association was found between self-reported moderate-to-vigorous PA (MVPA) or BMI and COVID-19 related outcomes. Although no causal association was found by MR analyses, this may be due to limited power and we conclude policies to encourage and facilitate exercise at a population level during the pandemic should be considered.

Investigation and analysis on characteristics of a cluster of COVID-19 associated with exposure in a department store in Tianjin / 中华流行病学杂志

Objective@#To describe the epidemiological characteristics of a cluster of COVID-19 cases reported in Baodi district of Tianjin as of 18 February, 2020, which might be associated with the exposure in a local department store, and provide suggestions for prevention and control strategy development.@* Methods@#The basic characteristics, time and area distributions, clinical manifestations, epidemiological history and transmission mode of the COVID-19 cases associated with the department store exposure were analyzed.@* Results@#A total of 40 COVID-19 cases were associated with the department store exposure, accounting for 75.47% of the total confirmed cases (53 cases) reported in Baodi district. The cases were mainly at the age of 60 years or older (35.00%) and farmers (40.00%). The main clinical manifestations included fever (95.00%), cough (35.00%), and diarrhea (15.00%). The proportion of confirmed severe cases was 32.50%. The incidence curve showed that the incidence peak occurred on 31 January, 2020. Among the 40 cases, 6(15.00%) were department store employees, 19(47.50%) were customers and 15(37.50%) were close contacts (secondary cases). The first case occurred on 21 January, 2020, this case was a department store employee who had a purchasing history at whole sale markets in other provinces and cities before the onset, and 3 employees were still on duty after symptom onsets. The median of the incubation period of customer cases was 6 days, and the median of the interval between onset and medical treatment of customer cases was 7 days.@* Conclusion@#This was a cluster epidemic of COVID-19, which might be associated with the exposure in the department store. By now, the current prevention and control measures have achieved satisfied effects.

Lever-pivot balance: a neodoxy on treatment for intertrochanteric femoral fractures / 中华创伤杂志

Intertrochanteric femoral fractures are common in clinical practice and the key to treatment is timely stable fixation and early rehabilitation to prevent bedridden complications. At present, the failure of common internal fixation system in the treatment of unstable intertrochanteric femoral fractures is not rare. The authors think that for the normal anatomical type of leverage structure of human proximal femur, pivot can bear weight and complete multidirectional activities because its pivot is close to the center of the body. The intertrochanteric femoral fractures destroyed the trabecular structure on the tension side and pressure side. At the same time, the physiological lever of the proximal femur was destroyed. The cause for the failure of the existing internal fixation is the inability to reconstruct the physiological pivot. Based on the anatomical and biomechanical characteristics of the proximal femur, the author reviewed the previous literatures and analyzed the problems in the treatment of intertrochanteric femoral fractures, and for the first time raised the " lever-pivot balance" theory for the treatment of intertrochanteric femoral fractures. This theory opens a new way for solving the problems in treatment of intertrochanteric femoral fractures.

Investigation and analysis of tuberculosis prevention and control in schools in Tianjin / 公共卫生与预防医学

Objective To understand the current situation of tuberculosis (TB) prevention and control in schools, and to provide a basis for further improving school TB prevention and control strategies. Methods A survey of 387 schools in Tianjin was conducted. The data was statistically analyzed by chi-square test. Results Most of the schools implemented the TB prevention and control work well, including leadership responsibility, work plan and epidemic report. However, the leadership responsibility (72.34%, 34/47) and the work plan (68.09%, 32/47) in colleges and universities were not well implemented. The proportion of full-time health care personnel in schools with more than 600 students was relatively low, which was 1:2 497 in primary schools, 1:1 537 in secondary schools, and 1:2 673 in colleges and universities. The proportion of morning and afternoon checking (27.66%) and sickness absenteeism tracking (82.98%) was low in colleges and universities. There was a lower proportion of new students carrying out TB test in primary schools and secondary schools (χ2=26.05，P<0.001). The colleges and universities had a low proportion of TB check-up among students in schools and students in high epidemic areas (P<0.001). The screening rate of students who had close contacts with TB patients in primary schools was low (P<0.001). The proportion of preventive treatment in schools at all levels was low (P<0.001). Conclusion Schools at all levels in Tianjin need to utilize additional school health care personnel and increase the proportion of latent infection patients receiving preventive treatment. Primary and secondary schools should further standardize the physical examination of new students and the treatment of epidemic situation. It is necessary for colleges and universities to establish multi-level tuberculosis surveillance networks and carry out active screening.

Effect of branched chain amino acid on apoptosis of neurons after focal cerebral ischemia in rats / 中华临床营养杂志

Objective To investigate the regulatory effect of branched chain amino acids (BCAA) on the expression of apoptosis related proteins after cerebral ischemia reperfusion injury and the protective effects of BCAA on ischemic brain injury in rats.Methods 40 male SD rats were randomly divided into normal diet group (n =20) and branched chain amino acid (BCAA) group (n=20) according to the random number table,and each group was randomly divided into control group (n=6),sham operation group (n=6) and model group (n =8) which used suture method to make ischemia reperfusion model.After modeling,modified Neurological Severity Scores (mNSS) was used to access the neurological impairment degree of 2,6,24,48 and 72 h in each group.The expression of apoptosis related proteins (Cleaved,Bax/Bcl-2) after 72 h was detected by the method of immune protein imprinting (Caspase3) and compared between normal diet group and BCAA group.Results Compared with the normal diet rats,the mNSS of BCAA diet rats after modeling at 2,6,24,48,72 h decreased (11.35±2.78 vs.7.15±2.41,P=0.019;9.35±1.75 vs.5.82±1.17,P=0.002;6.11±1.16vs.4.39±1.46,P=0.048;5.87±1.32vs.3.55±1.94,P=0.036;4.98±2.24vs.2.09±1.33,P=0.022).The expression of cleaved caspase3 protein and the ratio of Bax/Bcl-2 decreased in BCAA group.Conclusion BCAA can alleviate the apoptosis of rats after ischemia and reperfusion,reduce the damage of nerve function,and has a positive protective effect on ischemic brain injury.