Rat brain development is a complicated process.There are significant changes of histology, cytology and molecular biology in the process of fetal and postnatal brain development.The basic structure of brain has formed in the prenatal period.While the formation of connections between different parts and the improvement of the function of the brain occur after birth, during which many of the variations are bases of the nervous system diseases, so the postnatal brain development is still very important.Although the concept of brain microenvironment has been proposed more than 150 years ago, the research about the changing extracellular space ( ECS ) during the postnatal brain development has yet to gain significant progress.The author reviewed the anatomical and physiological characteristics of ECS in the process of postnatal development of the rat, stating the important role of ECS in the individual development, which is expected to provide reliable evidences for the explore of mechanisms and effective treatment approaches of pediatric development related nervous system diseases.

Objective To investigate the relationship between gene polymorphisms of homocysteine (Hcy), metabolic enzymes methylenetetrahydrofolate reductase MTHFR C677T and chronic pulmonary heart disease (CPHD). Methods The gene polymorphisms of MTHFR C677T were determined by the polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)in CPHD patients (n=120) and healthy control (HC, n=120), and genotyping was carried on. The automatic biochemistry analyzer was used to detect the level of Hcy and other related biochemical indicators. Results There was significant difference in Hcy level between the CPHD group and HC group (P<0.05). The mutation frequencies of CC, CT and TT were 24.17%, 43.33%and 32.50%, 35.00%, 47.50%and 17.50%in the CPHD group and HC group. The mutation frequencies of allele C/T were 45.83%and 54.17%in HC group, and 58.75%and 41.25%in control group. There was significant difference in the overall frequency distribution between the three genotypes (χ2 =8.010, P<0.05). The frequency of T allele was significantly higher in CPHD group than that in control group (χ2=8.025,P<0.05). Conclusion The increased Hcy and its metabolic enzyme MTHFR C677T may be involved in the occurrence and development of CPHD.

Alpha-glycerophosphate oxidase (alpha-GPO) from Enterococcus casseli flavus was successfully isolated and purified by using polyethylene glycol (PEG)/(NH4)2SO4 aqueous two-phase system (ATPS). The results showed that the chosen PEG/(NH4)2SO4 ATPS could be affected by PEG molecular weight, pH, concentration of PEG and (NH4)2SO4, and inorganic salt as well as additional amount of crude enzyme. After evaluating these influencing factors, the final optimum purification strategy was formed by 16.5% (m/m) PEG2000, 13.2% (m/m) (NH4)2SO4, pH 7.5 and 30% (m/m) additive crude enzyme, respectively. The NaCl was a negative influencing factor which would lead to lower purification fold and activity recovery. These conditions eventually resulted in the activity recovery of 89% (m/m), distribution coefficient of 1.2 and purification fold of 7.0.
Ammonium Sulfate ; chemistry ; Glycerolphosphate Dehydrogenase ; chemistry ; isolation & purification ; Molecular Weight ; Polyethylene Glycols ; chemistry ; Water

This paper is aimed to investigate the effect of fluid shear stress on the tight junction of laryngeal squamous carcinoma (Hep2) cells and to explore the potential molecular mechanism. Hep2 cells were selected and subjected to the fluid shear stress of 1.4 dyn/cm2 for different time, respectively. The morphological changes of Hep2 cells under shear stress were observed using inverted microscope. The cell-cell junctions were examined by transmission electron microscope (TEM). The expressions of tight junction proteins (including Occludin, Claudin-5 and ZO-1) and the distribution of Claudin-5 were examined by Western blot assay and laser scanning confocal microscope, respectively. The results indicated that Hep2 cells turned to spindle-like shapes after exposed to shear stress, and showed the trend of the recovering to original shapes when the shear stress was cancelled. The cell-cell junctions were tight under the shear flow condition, and the permeability was reduced under the condition of 1.4 dyn/cm shear flow. The expressions of tight junction proteins were enhanced with increased duration of shear flow, but reduced after removing shear flow. The result of Claudin-5 expression by immufluorescence assay was consistent with that by Western blot. The Claudin-5 mainly distributed in the cytoplasm under static condition, while it located at the intercellular after shear flow stimulation, and it appeared intercellular and cytoplasm after stopping shear flow stimulation. Therefore, it can be concluded that shear stress changes the morphology of laryngeal squamous carcinoma Hep2 cells, and upregulates the tight junction.
Blotting, Western ; Carcinoma, Squamous Cell ; pathology ; Claudin-5 ; metabolism ; Hep G2 Cells ; Humans ; Laryngeal Neoplasms ; pathology ; Occludin ; metabolism ; Stress, Mechanical ; Tight Junctions ; Zonula Occludens-1 Protein ; metabolism

Objective To analyze the cancer mortality and epidemiological characteristics of digestive system cancer in Xianyou County, Fujian Province, and to provide a scientific evidence for formulating preventive measures for digestive system cancer. Methods Excel and SPSS software were used to collect the monitoring data of digestive system cancer death in Xianyou County from 2014 to 2018, and then analyzed the mortality, the standardized rate (according to the Chinese 2000 population census) and the cause of death. Results From 2014 to 2018, the deaths of malignant tumors in Xianyou County accounted for 35.00% of all deaths. Among them, the four common digestive system malignant tumors (gastric cancer, esophageal cancer, liver cancer and colorectal cancer) accounted for 62.44% of malignant tumors. Gastric cancer ranked first and accounted for 27.36%. Average annual rate of crude mortality and standardized mortality of malignant tumor in the digestive system were 108.93/10⁵ and 89.34/10⁵, respectively, and the ratio of male to female was 2.27 to 1. Significant differences were found between town and village, as the terrain gets lower, the death rate goes down gradually. Compared with the data of 2011-2012, the standardized death rate of gastric cancer, esophageal cancer and liver cancer were reduced by 29.71%, 23.92% and 12.06%, respectively, while the rate of colorectal cancer was increased by 28.80% and the average annual growth rate was 7.83%. Conclusion Although the death rates of gastric cancer, esophageal cancer and liver cancer have decreased significantly, the malignant tumor of the digestive system is still the main disease that causes the death of residents in Xianyou County, Putian City. Therefore, it is necessary to strengthen the education of health in order to achieve the early discovery, diagnosis and treatment.

The mechanism of tinnitus remains undear.Currently,in addition to tinnitus induced by ear disea-ses,various systems of the body are also involved in the pathogenesis of tinnitus.Obstructive sleep apnea hypopnea syndrome(OSAHS)may be related to tinnitus,which has garnered increasing attention in recent years.This article reviews the latest research progress on the occurrence and possible mechanism of tinnitus in OSAHS,shedding new light on the treatment of tinnitus.

Objective: To design the self-rating scale on basic ability in graduates of preventive medicine major, and test its reliability and validity, providing a reliable tool for evaluating the basic ability of graduates. Methods: On the basis of constructing the Evaluation Index System on Basic Ability in Graduates of Preventive Medicine Major, the three-level indexes were converted to specific questions. Self-evaluation scale including 58 items, 22 sub-dimensions and 8 main dimensions were finally designed after pre-survey and expert argumentation. A total of 205 graduates of preventive medicine major from a medical college and 9 experts in the field of public health were selected to completed the questionnaire. Scale's reliability was tested by applying internal consistency reliability and composite reliability; it's validity was tested by applying content validity and confirmatory factor analysis. Results: Scale's α coefficient of internal consistency reliability was 0.976; α coefficient and combination reliability of eight main dimensions were both higher than 0.8; the content validity index S-CVI of the scale was 0.94, the content validity index I-CVI of the item level was 0.78 to 1.00; the average variance extraction amount (AVE) of the eight main dimensions was higher than 0.50. Fitting of the structural model with the item used as observation indexes was reasonable (χ²/df=1.749, RMR=0.036, RMSEA=0.061, NFI=0.801, IFI=0.904, TLI=0.904, CFI=0.903), and the sub-dimension as used observation indexes was good(χ²/df=1.876, RMR=0.032, RMSEA=0.066, NFI=0.913, IFI=0.958, TLI=0.945, CFI=0.957). Conclusion This scale is the first self-rating scale on the basic ability in graduates of preventive medicine major on the basis of the National Standards of Teaching Quality on Public Health and Preventive Medicine, with good reliability and validityl. It is able to achieve quantitative evaluation on graduates' basic abilities.

Objective:To construct a set of evaluation index system for the core ability of preventive medicine graduates to respond to sudden biological public health events.Methods:Research methods such as in-depth interviews and group discussions were used to determine the core competence structure, the Delphi method was used to conduct two rounds of expert consultation, and the index system and its weights were finally determined based on the consultation results of 21 experts on the system. Excel and SPSS 21.0 were used for data collation and statistical analysis.Results:The positive coefficient of expert consultation was greater than 80%, the authority coefficient was greater than 0.7, and the average was 0.906. The final index system was composed of 4 first-level indicators, 10 second-level indicators, and 39 third-level indicators.Conclusion:The evaluation index system can provide a reference for exploring effective ways to improve the core competence of graduates.

Optical coherence tomography angiography (OCTA) is an emerging technique for retinal angiography, which images with movement contrast of red blood cells and has the advantages of fast acquisition, high imaging quality and no need of additional contrast agent. Since it was approved by FDA for retinal evaluation in 2015, it has been widely used in the research of nervous system diseases. This article reviews the application of OCTA in nervous system diseases to provide reference for the research of neurological diseases.

Objective To investigate the CT manifestations and clinical features of thymic lymphoepithelioma-like carcinoma(LELC)in children.Methods The CT findings and clinical features of 5 children with LELC confirmed by pathology were analyzed retrospectively,and relevant literatures were reviewed.Results All the five children showed a large soft tissue mass(a few punctuate calcifications in 3 cases)in the anterior and middle mediastinum,which was lobulated.After enhancement,the tumor showed signifi-cant heterogeneous enhancement with cystic,necrosis,compressing,surrounding and invading adjacent structures.Twenty-one children with LELC were searched in literatures.Conclusion Thymic LELC in children usually occurs in adolescent boys aged 10-16 years.Those children usually go to the doctor with symptoms of tumor compression or invasion of adjacent structures.LELC shows advanced clinical stage with poor prognosis.CT enhancement can accurately display the lesion and invasion of adjacent structures,and guide clinical staging and treatment.