Objective: To quantitatively compare five occupational health risk assessment models in assessing silica dust hazard risk in small open pits, so as to provide the reference for the research of occupational health risk assessment methodology Methods : Seven small open pits were selected as the evaluation sites. The models from Singapore, the United Kingdom's Control of Substances Hazardous to Health Essentials ( COSHH Essentials ), Australia, Romania, and the International Council on Mining and Metals ( ICMM ) were applied to assessing the occupational health risk of the workers exposed to silica dust. The risk ratios ( RRs ) were calculated, and the parallelism, accuracy and correlation of the evaluation results of the five models were compared. Results : The RRs of the Singaporean model, COSHH model, Romanian model, Australian model and ICMM model were 0.8, 1.0, 0.4, 0.6 and 0.8, respectively. The Singaporean model and the Australian model were able to distinguish transport drivers from sprinkler drivers in the health risk exposed to silica dust, which was consistent with the actual risk of the two posts. Except for COSHH model, the RRs of the other four models were positively correlated ( P<0.05 ); the RRs were all positively correlated with concentration ratios ( CRs ) ( P<0.05 ), and the correlation coefficient between RRs and CRs of the Singaporean model was the largest (0.801). Conclusion Among the five models, the Singaporean model can more accurately evaluate the hazard risk of silica dust in posts of open pits, and has a good correlation with the other models.

VEGF nanoparticle (VEGF-NP) was prepared by a multi-emulsification technique using a biodegradable poly-dl-lactic-co-glycolic (PLGA) as matrix material. The nanoparticles were characterized for size, VEGF loading capacity, and in vitro release. VEGF-NP and naked VEGF plasmid were intramuscularly injected into the ischemia site of the rabbit chronic hindlimb ischemia model and the efficiency of VEGF-NP as gene delivery carrier for gene therapy in animal model was evaluated. Gene therapuetic effect was assessed evaluated by RT-PCR, immunohistochemistry and angiography assay. The average size of VEGF-NP was around 300 nm. The encapsulation efficiency of VEGF was above 96%. Loading amount of VEGF in the nanoparticles was about 4%. In vitro, nanoparticles maintained sustained-release of VEGF for two weeks. Two weeks post gene injection the capillary density in VEGF-NP group (81.22 per mm2) was significantly higher than that in control group (29.54 mm2). RT-PCR results showed greatly higher VEGF expression in VEGF-NP group (31.79au * mm) than that in naked VEGF group (9.15 au * mm). As a carrier system for gene therapy in animal model, VEGF-NP is much better than naked DNA plasmid. The results demonstrate great possibility of using NP carrier in human gene therapy.
Animals ; Disease Models, Animal ; Gene Transfer Techniques ; Genetic Therapy ; Genetic Vectors ; chemistry ; Lactic Acid ; chemistry ; Nanoparticles ; chemistry ; Plasmids ; Polyglycolic Acid ; chemistry ; Rabbits ; Vascular Endothelial Growth Factor A ; genetics

Objective To establish a rapid,high-efficiency and clean way to monitor and pretreat the radioactivity in foods.Methods Food samples,20 kg each of cabbage,crucian,shrimp,pork and 20 L of milk,were collected around Qinshan nuclear power plant,totaling 10 samples for each food.Each type of foods was arranged in two groups each with 10 samples.Samples were pretreated using traditional ashing method (TAM) and microwave ashing method (WAM) separately.HDEHP were used for 90Sr separation and measurement.Calculations were made for the time spent on food pretreatment.The ash-fresh ratio and the recovery rate of 90Sr by the two different method were calculated,with the quality of ash being evaluated.Results The mean time spent on pretreatment was cabbage 20 h,crucian 54 h,shrimp 46 h,pork 58 h and milk 74 h for TAM group,and cabbage 8.5 h,crucian 26 h,shrimp 23 h,pork 26 h and milk 30 h for WAM group,respectively.The time spent by WAM was half the time less than by TAM,especially for animal edible product.The ash-fresh ratios from WAM group were higher than from TAM group.The recovery rates of 90Sr from WAM group in the analytical process were all above 75％,higher than from TAM group.Ashes produced by WAM were hoary,uniform,carbon residue-free and fully ashed.Conclusions WAM pretreatment can pretreat food rapidly,efficiently,cleanly with less loss and better ashing effect.These can meet the requirement of rapid pretreatment of radioactivity in food.

T-cell acute lymphoblastic leukemia (T-ALL) is derived from the malignant transformation and clonal proliferation of precursor T cells. T-ALL is usually associated with the genetic mutations and/or chromosomal translocation, thus causing the change of survival, proliferation and progenitor cell differentiation of T cells in T-cell development. Studies have shown that Wnt signaling pathway plays a key role in the regulation of hematopoietic stem cell and normal T-cell development, and it is also abnormally altered in T-ALL. This article reviews the research progress of the mechanism of Wnt signaling pathway in T-ALL development.

BACKGROUND:Biomimetic design of bioactive materials to restore,maintain or improve the function of tissue based on the understanding of anatomy on the function and structure of biological tissue is a research hotspot in the field of regenerative medicine at present. OBJECTIVE:To discuss the effect of mechanical properties,three-dimensional spatial structure,and biochemical activity of biomedical scaffolds on cell behavior and review the application of biomedical scaffolds in the field of tissue engineering. METHODS:The articles published in CNKI,Wanfang,Web of Science,and PubMed databases from January 2003 to April 2023 were searched by computer.The Chinese search terms were"extracellular matrix,tissue engineering,scaffolds,biomaterials,biomimetic structures,mechanical properties,three-dimensional structures,tendon-bone interface,osteochondral,neural conduits,artificial blood vessels".English search terms were"extracellular matrix,tissue engineering,scaffolds,biomimetic structures,biomaterials,tendon bone interfaces,osteochondral,neural conduits,artificial blood vessels". RESULTS AND CONCLUSION:Cells are in a complex and dynamic three-dimensional environment,so the extracellular matrix is the ultimate target of biomaterial simulation.The bionic structure of biomedical scaffolders needs to be similar to the real microenvironment,so that cells can stick to the wall,grow and migrate normally,and maintain their diverse physiological functions.Biomimetic design of extracellular matrix in terms of mechanical properties,three-dimensional spatial structure,and biochemical properties of biomedical scaffolds can play a decisive role in tissue repair,thus affecting the final result of tissue repair.Biomimetic biomedical scaffolds have been widely used in tendon-bone interface,bone cartilage interface,nerve,vascular regeneration,and other fields,providing a promising new idea in clinical practice.

Objective To summarize the clinical feature,gene mutations,diagnosis,treatment,and follow-up data of protein-sensitive hypoglycemia,so as to improve the clinical understanding of the disease.Methods Five patients were diagnosed with protein-sensitive hypoglycemia during June in 2015 and December in 2017 from the Department of Pediatric Endocrinology and Inherited Metabolic Diseases,Children's Hospital of Fudan University.Clinical data of 5 cases were summarized,including clinical manifestations,findings of protein sensitivity test,therapy effect and prognosis.The endocrine and metabolic panel was used to investigate the genetic cause of four patients.Related literatures of protein-sensitive hypoglycemia were reviewed,and the phenotypes,genotypes,and therapy effects were summarized.Results Among the 5 patients diagnosed with positive results of protein-sensitive hypoglycemia,three were found to harbor glutamate dehydrogenase 1 (GLUD 1) mutations (c.965G ＞ A,p.R322H:2 cases;c.943C ＞T,p.H315Y:1 case),and another one had complex heterozygous mutations in L-3-hydroxyacyl-CoA dehydrogenase (HADH,c.29G ＞ C,p.R10P;c.89T＞ A,p.V30E).5 patients were euglycemia without any medical support after low protein diet.In 18 literatures retrieved and this study,there were totally 161 cases of protein-sensitive hypoglycemia (149 cases with GLUD1 mutations and 10 cases with HADH mutations).Conclusions When a child was admitted because of hypoglycemia,the diagnosis of protein-sensitive hypoglycemia should be suspected if he or she also had postprandial hypoglycemia,with or without hyperammonemia.Protein sensitivity test is helpful for us to make the diagnosis of protein-sensitive hypoglycemia.

Objective: To investigate the epidemiological characteristics of norovirus clustering and outbreaks in schools and kindergartens in China, so as to provide references for prevention and control of outbreaks. Methods: A descriptive epidemiological method was used to analyze outbreaks of Norovirus in schools and kindergartens in China during 2014-2018 , the indicators which was analyzed and compared including attack rate, duration of the outbreak, reporting interval. Results: A total of 832 Norovirus outbreaks were reported by schools and kindergartens in China from 2014 to 2018. The total number of outbreaks showed an upward trend with an average annual growth rate of 58%. The number of reported cases was 40 445 but there was no death. Norovirus outbreaks mainly occurred in primary schools (42%), followed by kindergartens and middle schools (both 24%), university (6%) and 77 outbreaks (4%) were reported in universities and other schools. The peak seasons were March to May, November and December each year. Jiangsu Province and Guangdong Province (both 22%) reported the largest number of outbreaks. The main transmission of norovirus outbreaks was through direct person contact (72%), foodborne (4%) and waterborne (3%) caused fewer outbreaks than direct person contact. The duration of the epidemic was positively correlated with the reporting interval (r=0.63, P<0.05) and the number of cases per outbreak (r=0.51, P<0.05). Conclusion Disinfection treatment of vomitus should be standardized in schools and kindergartens. Timely detection, reporting, disposal of the epidemic can effectively control the spread of norovirus outbreaks.

Objective:To investigate the levels of gross radioactivity in drinking water and of 90Sr in food around Sanmen nuclear power plant (NPP) before and after operation. Methods:From 2012 to 2019, 7 drinking water monitoring sites were selected around the Sanmen NPP to collect source water, factory water and peripheral water, respectively, in order to measure and analyze the total radioactivity level in drinking water. Based on the dietary habits of local residents, 4 kinds of food such as grains, vegetables, freshwater fish and marine fish grown locally were sampled to measure and analyze the activity concentration of 90Sr. Results:Before the operation of Sanmen NPP, the total α radioactivity and total β radioactivity in drinking water around the NPP were 0.001-0.063 Bq/L and 0.019-0.210 Bq/L, respectively. After operation, the total α radioactivity and total β radioactivity were 0.001-0.084 Bq/L and 0.025-0.079 Bq/L, respectively. Both were lower than the national standard value given in the GB 5749-2006 " Sanitary standards for drinking water" . There was no significant change in the radioactivity level of source water, factory water and peripheral water during the wet and dry periods. The activity concentration of 90Sr in these four types of food ranged from 0.037 to 1.216 Bq/kg before operation and from 0.049 to 0.692 Bq/kg after operation, all lower than the standard value of " Standard for the concentration in radioactive substances in food" (GB 14882-94). Conclusions:Before and after the operation of Sanmen NPP, the total α and total β radioactivity in drinking water and 90Sr activity concentration in food are stable, below the national standard limit.

Homocysteine participates in the methionine cycle in the body and is excreted by the kidneys. Its abnormal elevation increases the risk of cerebrovascular disease. Studies in recent years have shown that hyperhomocysteinemia is closely related to cerebral small vessel diseases and is an independent risk factor for ischemic stroke and cognitive impairment. Because hyperhomocysteinemia is largely reversible, the significance of drug intervention in the prevention and treatment of cerebrovascular disease has gradually been confirmed. This article reviews the relationship between homocysteine and cerebral small vessel diseases in order to provide a reference for the prevention of stroke and dementia.

Objective To summarize the pathological survey of time-zero renal biopsy (T0-RBx ) . Methods The material qualities and pathological features were analyzed retrospectively for T 0-RBx (n=176) between March 2008 and May 2016 .According to the source of donor kidney ,T0-RBx specimens were divided into living donors (LD) group (n=137) and Deceased donation (DD) group (n=39) .Furthermore , the DD group was divided into cerebral hemorrhage group (n= 10) and brain trauma group (n= 29) according to the causes of death .The inter-group differences of pathological characteristics and the effects of abnormal pathological lesions on allograft function were observed .Results All T0-RBx specimens contained cortical kidney tissue .The average microscopic length of renal tissue was (0 .39 ± 0 .23) cm and the median glomerular number 11 . The abnormal pathological lesions included glomerulosclerosis (GS ,30 .7 ％ ) , segmental glomerulosclerosis (1 .1 ％ ) ,mesangial increase (MI ,19 .3 ％ ) ,tubular atrophy (TA ,35 .2 ％ ) , acute tubular necrosis (ATN ,9 .1 ％ ) ,vacuolar degeneration of tubular epithelium (27 .3 ％ ) ,losses in tubule epithelial brush border (97 .7 ％ ) , protein cast (25 ％ ) , interstitial fibrosis (IF ,34 .1 ％ ) , inflammation (I ,42 .6 ％ ) ,arteriolar hyalinosis (AH) (26 .1 ％ ) and vascular fibrous intimal thickening (CV ,23 .3 ％ ) .Among them ,23 .9 ％ ,1 .1 ％ ,0 .55 ％ and 0 .55 ％ cases were diagnosed as IgA nephropathy ,immune complex associated with glomerular disease and focal segmental glomerulosclerosis diabetic nephropathy respectively .And the reminders were of ischemic injury .The incidence rates of TA ,IF and I were lower in DD group than those in LD group ( P< 0 .05 ) . However , ATN and vacuolar degeneration of tubular epithelium were higher (P<0 .001) .The incidence of GS was significantly higher in cerebral hemorrhage group than that in brain trauma group (P<0 .01) .No statistical difference existed in other lesions or disease constitution among the groups (P>0 .05) .Further analysis showed GS was related with allograft function at 6/12 months post-transplantation in both LD and DD groups (P<0 .05) .IF and AH were also related to short-term renal function of recipients post-transplantation in LD and DD groups (P>0 .05) .Conclusions T0-RBx may detect the abnormal lesions of donor kidney .Some differences exist in types and degree of abnormal lesions among different donor kidneys .LD group has a higher risk for chronic histological injury such as TA and IF while DD group is more susceptible to acute renal tubular interstitial injury .Thus it is valuable for predicting allograft function post-transplantation .Material quality is essential for ensuring the reliability of T 0-RBx .