Objective:To investigate serum vitamin A and vitamin D status in children aged 2-<7 years in 20 cities in China.Methods:A cross-sectional study was conducted. A total of 2 924 healthy children aged 2-<7 years were recruited from September 2018 to September 2019 from 20 cities in China, categorized by age groups of 2-<3 years, 3-<5 years, and 5-<7 years. The demographic and economic characteristics and health-related information of the enrolled children were investigated. Body weight and height were measured by professional staff members. The serum vitamin A and vitamin D levels were detected by high-performance liquid chromatography-tandem mass spectrometry. Chi-square test and Logistic regression were applied to analyze the association between vitamin A and vitamin D deficiency and insufficiency as well as their underlying impact factors.Results:The age of the 2 924 enrolled children was 4.33 (3.42, 5.17) years. There were 1 726 males (59.03%) and 1 198 females (40.97%). The prevalences of vitamin A and vitamin D deficiency in enrolled children were 2.19% (64/2 924) and 3.52% (103/2 924), respectively, and the insufficiency rates were 29.27% (856/2 924) and 22.20% (649/2 924), respectively. Children with both vitamin A and vitamin D deficiencies or insufficiencies were found in 10.50% (307/2 924) of cases. Both vitamin A ( χ2=7.91 and 8.06, both P=0.005) and vitamin D ( χ2=71.35 and 115.10, both P<0.001) insufficiency rates were higher in children aged 3-<5 and 5-<7 years than those in children aged 2-<3 years. Vitamin A and vitamin D supplementation in the last 3 months was a protective factor for vitamin A and D deficiency and insufficiency, respectively ( OR=0.68 and 0.22, 95% CI 0.49-0.95 and 0.13-0.40, both P<0.05). The rates of vitamin A and D insufficiency was higher in children with annual household incomes <60 000 RMB than in those with annual household incomes ≥60 000 RMB ( χ2=34.11 and 10.43, both P<0.01). Northwest and Southwest had the highest rates of vitamin A and vitamin D insufficiency in children aged 2-<7 yeas, respectively ( χ2=93.22 and 202.54, both P<0.001). Conclusions:Among 20 cities in China, children aged 2-<7 years experience high rates of vitamin A and vitamin D insufficiency, which are affected by age, family economic level, vitamin A and vitamin D supplementation, and regional economic level. The current results suggest that high level of attention should be paid to vitamin A and vitamin D nutritional status of preschool children.

Clinical trials are an important method for evaluating the safety and efficacy of in vitro diagnostic reagents, and are a key basis for product registration review and approval. In order to strengthen the management of clinical trials of in vitro diagnostic reagents, the National Medical Products Administration and relevant departments have formulated a series of regulations at the regulatory level, and require applicants and clinical trial institutions to establish a quality management system for clinical trials of in vitro diagnostic reagents. Medical laboratory is the main department and implementer of in vitro diagnostic reagent clinical trials in medical institutions. In recent years, with the rapid development of the in vitro diagnostic industry, the clinical trial projects of in vitro diagnostic reagents conducted by medical laboratory have been increasing day by day. However, there are currently few discussions on the clinical trial of in vitro diagnostic reagents from the perspective of researchers. Therefore, this article summarizes the characteristics of clinical trials of in vitro diagnostic reagents, analyzes the problems and difficulties in conducting clinical trials of in vitro diagnostic reagents in current medical laboratories, and introduces the laboratory′s experience in management; to provide reference for medical testing laboratories that have not yet conducted or have already conducted clinical trials of in vitro diagnostic reagents, in order to improve the quality and efficiency of clinical trials.

Clinical trials are an important method for evaluating the safety and efficacy of in vitro diagnostic reagents, and are a key basis for product registration review and approval. In order to strengthen the management of clinical trials of in vitro diagnostic reagents, the National Medical Products Administration and relevant departments have formulated a series of regulations at the regulatory level, and require applicants and clinical trial institutions to establish a quality management system for clinical trials of in vitro diagnostic reagents. Medical laboratory is the main department and implementer of in vitro diagnostic reagent clinical trials in medical institutions. In recent years, with the rapid development of the in vitro diagnostic industry, the clinical trial projects of in vitro diagnostic reagents conducted by medical laboratory have been increasing day by day. However, there are currently few discussions on the clinical trial of in vitro diagnostic reagents from the perspective of researchers. Therefore, this article summarizes the characteristics of clinical trials of in vitro diagnostic reagents, analyzes the problems and difficulties in conducting clinical trials of in vitro diagnostic reagents in current medical laboratories, and introduces the laboratory′s experience in management; to provide reference for medical testing laboratories that have not yet conducted or have already conducted clinical trials of in vitro diagnostic reagents, in order to improve the quality and efficiency of clinical trials.

As resident immune cells of central nervous system(CNS),microglia play a key role in immune surveillance and tissue repair.They can be activated by various types of pathological factors to form M1 or M2 phenotype,which mediates neuroinflam-mation or neuroprotective effects.At the same time,when the homeostasis of the microenvironment in which the neuron is located is broken,"signal"molecules are also released to induce microglial activation through ligand-receptor binding.Therefore,the regulation of microglia-neuron connection is of great significance for treatment of nervous system diseases.This article reviews the signaling mole-cules involved in the two-way interaction between microglial cells and neurons,and elucidates the immune mechanisms of microglia-neuron,thus providing a basis for targeted treatment of CNS diseases related to microglia activation.

Three different preclinical evaluation methods of MTF through-frequency response, MTF through-focus-response and expected visual acuity were used to compare and analyze the imaging differences of IOLs with four different optical designs. The research work could be used in the simultaneous vision IOLs in the optical design stage and verify the optical quality of the IOLs, the results can predict the visual representation of the patients better. The evaluation results can provide reference for IOL manufacturers and users in product design, development, validation and application selection.
Humans ; Prosthesis Design ; Lenses, Intraocular ; Vision, Ocular ; Visual Acuity

The study explored the methods of determining the diameter of clear optic of intraocular lenses by analyzing the design principles and influencing factors of clear optic. Measure and compare the clear optic diameters of intraocular lenses from -10.0 D to 36.0 D respectively. The measurement results of the two methods have good consistency and can be used in the measurement of clear optic. But considering the accuracy and convenience of actual measurement, profile projector measurement principle is more suitable for conventional mass production testing. The Schlieren technique method can provide more useful information in product development and feature description stage, and can be used as an auxiliary verification method for clear optic diameter measurement.
Eye ; Lenses, Intraocular ; Optics and Photonics ; Prosthesis Design

Objective: This study aims to explore factors associated with parental mediation of children’s vision care and digital technology use. Methods: By using a probabilityproportionate sampling method, a total of 3 249 parents of junior primary school students completed the selfadministered questionnaire in second semester of 2018 from Taipei and Pingtung. Results: Parents had moderate scores in children’s vision care beliefs, selfefficacy and parental mediation. Children spent an average of 7 hours on digital technology use per week. Multiple regression analysis results showed that parents who had intact family, not providing children with personal digital technology devices, spent less time in digital technology devices, and had higher levels of vision care beliefs, higher mediation efficacy, and more cues to action were more likely to have higher levels of vision care mediation behaviors. Whereas children who were at senior grades, low household income, from nonintact families, owned personal digital technology devices, whose parents spent more time using digital technology devices and implementing low levels of parental mediation were more likely to spend more time using digital technology devices. Conclusion Schools and communities could provide more parental training and parentchild colearning opportunities to enhance parental mediation of children’s vision care behavior and reduce excessive digital technology use.

Objective To investigate the expression level of hypoxia-inducible factor-lot (HIF-1ot) in gastric cancer and its relationship with clinicopathological characteristics and prognosis of patients with gastric cancer.Methods From March 3,2011 to September 28,2012,49 patients with gastric adenocarcinoma tissue chips were selected from pathology department of our hospital.They were matched with paracancerous tissues.The expression levels of HIF-1α were measured by immunohistochemistry method in gastric cancer tissues and paracancerous tissues chips.Kaplan-Meier was used to evaluate the progression-free survival (PFS) and overall survival (OS),and the Cox proportional hazards model was used to analyze whether HIF-1α was a prognostic factor.Results The high expression rate of HIF-1α protein in gastric cancer was significantly higher than that in paired para-carcinoma group (42.9％ vs.4.1％,x2 =20.509,P ＜ 0.001).The expression of HIF-1 α protein was related to TNM stage (x2 =4.601,P =0.032),vascular invasion (x2 =6.766,P =0.009) and degree of differentiation (x2 =7.969,P =0.005).Compared with patients with low expression of HIF-1α,the median PFS (16.2 months vs.27.3 months) and median OS (34.8 months vs.43.8 months) were shorter in the patients with high expression of HIF-1 α,and the differences were statistically significant (median PFS:x2 =4.661,P =0.002;median OS:x2 =6.903,P =0.009).The results of single factor analysis showed that overexpre-ssion of HIF-1α was correlated with PFS and OS (PFS:HR =4.461,95％ CI:1.969-10.802,P ＜0.001;OS:HR =3.109,95％CI:1.274-7.588,P =0.013).The results of Cox multivariate analysis showed that overexpression of HIF-1α was the independent risk factor that affected the survival and prognosis of patients with gastric cancer (PFS:HR =4.747,95％ CI:2.175-10.230,P ＜0.001;OS:HR =3.171,95％ CI:1.358-7.404,P =0.008).Conclusion The high expression rate of HIF-1α protein in gastric cancer tissues is significantly higher than that in paracancerous tissues.The expression of HIF-1α is associated with TNM stage,vascular invasion,degree of differentiation in patients with gastric cancer.The high expression of HIF-1α is associa-ted with the shorter median OS and PFS.The high expression of HIF-1α is an independent risk factor for the survival and prognosis of patients with gastric cancer,which is expected to be an independent marker of poor prognosis.

Background:In the pathogenesis of chronic gastritis,the changes of biological factors can affect the physiological barrier of gastric mucosa,increase the risk of injury of intercellular junctions,leading to disruption of mucosal barrier. Aims:To investigate the expressions of occludin and zonula occluden-1 (ZO-1)in chronic gastritis and their significance. Methods:A total of 82 patients with chronic gastritis from October 2014 to October 2017 at the First People's Hospital of Xiaochang were enrolled and divided into chronic non-atrophic gastritis (CNAG)group and chronic atrophic gastritis (CAG)group according to the endoscopic biopsy pathology. Forty healthy subjects were served as normal controls. Expressions of occludin and ZO-1 were examined by immunohistochemistry. Patients positive for Helicobacter pylori (Hp) infection received eradication therapy,and expressions of occludin and ZO-1 were reexamined after Hp eradication. Results:The positivity rates of occludin and ZO-1 proteins in CNAG and CAG groups were significantly lower than those in normal control group (P＜0.05). The positivity rates of occludin and ZO-1 proteins in CNAG group were significantly higher than those in CAG group (P＜0.05). The positivity rates of occludin and ZO-1 proteins in Hp-positive CNAG patients were significantly lower than those in Hp-negative CNAG patients (P＜0.05). The positivity rate of ZO-1 protein in Hp-positive CAG patients was significantly lower than that in Hp-negative CAG patients (P＜0.05). Expressions of occludin and ZO-1 proteins showed a linear trend correlation with activity of gastric inflammation (P ＜0.05);their expressions decreased significantly with the increase in activity of inflammation. The positivity rates of occludin and ZO-1 proteins in CNAG patients increased significantly after Hp eradication (P＜0.05). Conclusions:Expressions of occludin and ZO-1 are decreased in chronic gastritis,especially in CAG,and are correlated with Hp infection and activity of gastric inflammation.

OBJECTIVETo observe the changes in the expressions of microRNA-126 in myocardial tissue and cardiac troponin I (cTnI) in serum of rats in the early stage of severe burn injury with analysis of their relationship, and to validate the relationship between microRNA-126 and myocardial damage in cellular level.

METHODS(1) Forty-eight SD rats were divided into sham injury group (n=8, without fluid therapy after sham injury) and burn injury group (n=40, inflicted with 30% TBSA full-thickness scald on the back, hereinafter referred to as burn, and received intraperitoneally injection of lactic acid Ringer's solution) according to the random number table. Blood was collected from abdominal aorta of rats in sham injury group at post injury hour (PIH) 1, and then these 8 rats were sacrificed for obtaining left ventricular tissue. Blood was respectively collected from abdominal aorta of 8 rats in burn injury group at PIH 3, 6, 12, 24, and 48, and then they were sacrificed and the left ventricular tissue was obtained at each time point. The expression of microRNA-126 in myocardial tissue was assessed by real-time fluorescent quantitative RT-PCR. Serum level of cTnI was assessed by ELISA. (2) Rat myocardial cell line H9C2 was divided into normal control group (NC, routinely cultured), stimulation group (S), negative transfection+stimulation group (NT+S), and transfection+stimulation group (T+S) according to the random number table. Cells in S group were treated with hypoxia for 24 h after being cultured with DMEM containing 10% burn serum obtained from rats in burn injury group at PIH 6 in experiment (1). Cells in NT+S group and T+S group were respectively transfected with the negative control of microRNA mimics and microRNA-126 mimics for 24 h, and then were given the same treatment as that of S group. The expression of microRNA-126 in myocardial cells was determined by real-time fluorescent quantitative RT-PCR (with the sample number of 3). Cell counting kit 8 was used to examine the vitality of myocardial cell (with the sample number of 4, denoted as absorbance value). Apoptotic rate of myocardial cells was determined by flow cytometer (with the sample number of 3). Data were processed with one-way analysis of variance and LSD-t test. The relationship between microRNA-126 expression in myocardial tissue and serum level of cTnI of rats was assessed by linear correlation analysis.

RESULTS(1) Compared with that of sham injury group at PIH 1, the expression levels of microRNA-126 in myocardial tissue of rats in burn injury group at PIH 3, 6, 12, 24, and 48 were significantly decreased (with t values from 5.68 to 9.79, P values below 0.01), reaching its nadir at PIH 24 (0.40 ± 0.08). Compared with that of sham injury group at PIH 1, the serum levels of cTnI of rats in burn injury group at PIH 3, 6, 12, 24, and 48 were significantly increased (with t values from 6.68 to 12.79, P values below 0.01), peaking at PIH 12 [(1 035 ± 177) pg/mL]. A significant negative correlation between the expression level of microRNA-126 in myocardial tissue and serum level of cTnI was observed in rats of burn injury group at each time point (r=-0.797, P<0.001). (2) Compared with those of NC group, the microRNA-126 expression levels in myocardial cells of S group and T+S group were respectively decreased and increased (with t values respectively 4.57 and 5.73, P<0.05 or P<0.01), the cell vitality levels were obviously decreased (with t values respectively 14.88 and 6.48, P values below 0.01), and the apoptotic rates were significantly increased (with t values respectively 13.82 and 6.96, P values below 0.01). Compared with that in NT+S group, the microRNA-126 expression level in myocardial cells of T+S group was significantly increased (t=6.77, P<0.01), the cell vitality level was obviously increased (t=8.23, P<0.001), and the apoptotic rate was significantly decreased (t=6.14, P<0.001).

CONCLUSIONSExpression level of microRNA-126 in myocardial tissue of rat was decreased in the early stage of severe burn injury. It may participate in regulating myocardial damage and play a protective role.

Animals ; Burns ; metabolism ; pathology ; Cell Line ; Enzyme-Linked Immunosorbent Assay ; Hypoxia ; MicroRNAs ; genetics ; metabolism ; Myocardium ; metabolism ; pathology ; Myocytes, Cardiac ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; Serum ; Soft Tissue Injuries ; Transfection ; Troponin I ; metabolism