AIM: To analyze the effect of pigment epithelium derived factor (PEDF) on nitrogen monoxide (NO) and expression of cysteine-containing, aspartate-specific proteases-3 (caspase-3) in retinal tissues of model rats with optic nerve crush injury.METHODS: A total of 60 SD rats were randomly divided into the blank control group, model group and PEDF group, with 20 rats in each group.Except the blank control group, the optic nerve crush injury rat models were established in the other groups, and left eyeballs were taken as samples.After successfully modeling, the model group were treated with intravitreal injection of 5μL of balanced salt solution while PEDF group were treated with intravitreal injection of 5μL of PEDF (0.2μg/μL).Two weeks later, the retinal tissues were collected, and changes of shape were observed under microscope after HE staining.The changes of NO level were measured by colorimetry assay, the expression of caspase-3 mRNA and caspase-3 protein was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western-blot.RESULTS: HE staining showed that retinal tissues of the blank control group arranged neatly and clearly.Retinal ganglion cells (RGCs) arranged in a monolayer, and cells were oval, uniform in size and distribution, the cell nuclei were clear, closely arranged, with clear boundaries.The retinal tissues of the model group were sparse in shape, RGCs showed vacuolar changes, the overall number of cells was reduced, and cell nuclei of residual RGCs showed pyknosis and uneven staining.RGCs in PEDF group were with slightly edema and arranged closely, and the degree of injury was significantly milder than that in the model group.Levels of Caspase-3 mRNA and protein and NO levels in the three groups showed the model group > PEDF group > blank control group (all P < 0.05).CONCLUSION: The application of PEDF can down regulate the expression of Caspase-3 and NO in rates with optic nerve injury and reduce RGCs injury.

Objective To investigate the preparation of a biodegradable intravascular stent (BIS) with poly-l-lactic acid (PLLA), and to evaluate its physical and mechanical properties, as well as its biocompatibility. Methods The study of this BIS was first prepared by PLLA with molecular weight of 100 000 unit as the strut, and then the micro-porous structure was fabricated and the film was coated at the struts. Following the solidified shaping of BIS, the primary physical and mechanical properties of the BIS were tested, and 22 zigzag type BISs were implanted into the aorta and iliac arteries of 11 canines, then they were euthanized according to a fixed timetable for histopathological assessment. Results Two types of BIS (spiral and zigzag) were prepared, and the strut diameter of the BIS was 0.1-0.6 mm, stent diameter of BIS was 6-15 mm, and stent length was 30-80 mm. Of this BIS, the radial strength was 1.6-2.0 kPa (1 kPa=7.5 mm Hg), the dilatable rate was 6.0-6.5, the shortening rate was smaller than 8%-10%, and the proportion of stent surface area to open surface area was 0.16-0.18 (

Objective To investigate the relationship between the gene polymorphism of the inducible costimulatory molecules (ICOS),CD_(28),CD_(24) and susceptibility to multiple sclerosis(MS). Methods 83 patients with MS and 110 controls selected from healthy individuals and hospital staff in Chinese Han people with non-autoimmune diseases were studied by detecting genotype of the 3 genes using PCR-RFLP method. Results The frequency of ICOS-2394 TT genotypes was significantly higher in MS patients than in controls (MS 33.7%vs controls 10.9%, P

Age Distribution ; Aged ; China ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Sex Distribution ; Surveys and Questionnaires ; Tobacco Smoke Pollution ; statistics & numerical data

Objective To define the effect of drug eluting BIS with antiproliferation agent-paclitaxel in preventing vascular restenosis.Methods Bare BIS and drug BIS with 60 ?g paclitaxel were prepared. Both types of the BIS were implanted into the infrarenal restenosis aortas in canine models, and the animals were euthanized 6 weeks after implantation for histopathological, morphometric and immunohistochemical assessment.Results The mean lumen area of bare BIS group was (77 586.5?66.0) ?m2, and lumen of paclitaxel eluting BIS group was (113 435.9?71.0) ?m2. The mean neointima area of bare BIS group was (24 803?56) ?m2, and paclitaxel eluting BIS group was (12 931?63) ?m2. The PCNA-positive ratio was (38?15)% in bare BIS group and (11?0.31)% in paclitaxel eluting BIS group. The statistically significant difference between the two groups were noted ( P

OBJECTIVETo find out the situation of the implementation on "rules on stop smoking in the public places in Beijing", a study was carried out to compare the results from 1997 and 2001.

METHODSThousands of residents aged above 15 in a family were sampled by stratified sampling, and 4 districts were selected as study locales.

RESULTS(1) About 40% of the department or school leaders considered much about the work on banning of smoking with 70 % of the departments or schools having posters of signs on 'ban on smoking' in the meeting rooms. (2) Some of the departments or schools had inspectors looking after the issue. (3) 60% of the people had never or 10% had seen that the inspectors ever criticizing or punishing the smokers who violating the rules. (4) People still often saw some one would smoke in public (the rates were 19.53% , 37.89% , 6.35% respectively in 1997,2001,2004 ). (5) People received the information of these rules through TV news or newspaper.

CONCLUSIONAlthough success had been achieved since the implementation of the Rules, it did not seem to have had substantial progress.

Adolescent ; Adult ; Aged ; China ; Data Collection ; Humans ; Middle Aged ; Public Policy ; Public Sector ; Smoking Prevention

Objective As brucellosis epidemic is constantly rising in Harbin in recent years,we analyze the epidemic and surveillance results at municipal surveillance spots of brucellosis from 2008 to 2012,to find out the epidemic characteristics of Harbin brucellosis,and to provide scientific evidences for development of countermeasures.Methods Brucellosis surveillance data which were collected from the National Diseases Surveillance Information Management System from 2008 to 2010,the epidemic characteristics of Harbin brucellosis (including regional,time and population distribution) and the municipal surveillance results in Harbin (including epidemiological investigation and serological surveillance) were analyzed.Results A total of 1348 cases of brucellosis were reported in Harbin from 2008 to 2012,and the incidence of brucellosis increased from 1.79 per 100 000 to 4.62 per 100 000; in addition to Pingfang District (2008-2011) and Fangzheng County(2009 and 2011),all eighteen districts (counties or cities) in Harbin had reported epidemic in the past five years,the highest incidence was in Yilan (382 cases),and the incidence was significantly increased in Shuangcheng(111 cases) and Binxian(73 cases) in 2012; the time of onset focused on March to July,which accounted for 62.54％(843/1348) of annual incidence; age distribution,mainly young adults aged 30 to 60(71.59％,965/1348); gender distribution predominantly male (75.45％,1017/1348) ; occupational distribution farmers(84.87％,1144/1348),and the number of infected students and house workers were also high in the past five years(4.23％,57/1348 and 2.52％,34/1348).In the municipal surveillance spots from 2008 to 2012,13 010 cases were surveyed,of which 2695 cases received serological test,the positive rate was 3.93％ (106/2695),and the positive rate was increasing year by year.Conclusions The incidence of Harbin brucellosis is increasing year by year,onset season mainly in the spring and summer,young men with a high incidence,and farmers are main professional people.Brucellosis has also occurred among students,domestic workers,which should be vigilant.Therefore,we should further strengthen surveillance,timely analyze and report the epidemic,and provide a scientific basis to ensure each measure of eliminating the sources of infection put in place,vigorously develop health education,strengthen inter-departments cooperation,and control the spread of epidemic.

BACKGROUND:Human umbilical cord blood (CB)-derived CD133+ cells are a minority population of primitive cells with extensive proliferation and differentiation potentials,which are considered to have ability of neural differentiation.OBJECTIVE:We hypothesized a possible application of CB CD133+ cells in the cognitive and survival function of mice with dementia,the present study observed the changes of the cognitive function and survival of amyloid precursor protein(APP)transgenic mice after CB CD 133+ cells transplantation to verify the above assumption.DESIGN,TIME AND SETTING:A completely randomized block design of animal experiments was performed in the Hematology Institute of Tianjin Hematology Hospital from September 2005 to December 2007.MATERIALS:Forty-eight eight-month-old male APP 695 transgenic C57BL/6 (BDF1/KM) mice were selected in this experiments All mice were divided randomly into three groups:control group (n=8),CD133+ transplantation group (n=20) and CD133 transplantation group (n=20).METHODS:Mice in control groups received an intraventricular injection of 10 μL phosphate buffered saline (PBS).The transgenic mice that received an intraventricular injection of 10 μL CD133+ (5×104/μL) and CD133 CB cells (5×104/μL) respectively.MAIN OUTCOME MEASURES:Radial ann water maze (RAWM) was used to evaluate cognitive function of the mice and the survival days of mice in different groups were recorded,lmmunohistochemical assessments and Dil Fluorescence labeled way was used to detect the differentiation phenotype of transplanted cells.RESULTS:The cognitive function of the mice in CD133+ transplantation group was significantly improved compared with the mice in CD 133- transplantation and control groups both 30 and 180 days after transplantation (P＜0.05).The mean survival time of the mice in CD133+ transplantation group was significantly increased compared with CD133 transplantin group and control group (P＜0.05).It was observed that the transplantation CB CD133+ cells labeled with Dil migrated into several brain regions at day 30 post-transplantation.These cells were stained for human βⅢ-tubulin,neuralfilement(NF),neuron specific enolase (NSE),and glial fibriliary acidic protein(GFAP).However,in the brain of mice that received CD133 cells transplantation,CB cells were distributed mainly in and around the lateral ventricle at day 30 and 180 post-transplantation and GFAP-,βⅢ-tubulin- and NSE-positive cells were rarely detected.After intraventricular transplantation of CB CD133+ cells,the percentage of transplanted Dil-labeled CB cells expressing βⅢ-tubulin was significant higher at day 30 than at day 180,and the percentage of CB cells expressing NSE was significant lower at day 30 than that at day 180 (both P＜0.01).The percentage of CB cells expressing GFAP was relatively constant between the days 30 and 180 after transplantation (P＞0.05).CONCLUSION:The result of this experiment suggested that the cognitive and survival function improvement achieved by transplantation of CB CD133+ cells is mainly due to a replacement of dysfunctional cells or augmentation of neural circuit by CB CD133+ cells transplantation.

BACKGROUND: At present, hemopoietic stem cells have been proved to differentiate into nerves in rodents animals. As for the human, this topic is in debate.OBJECTIVE: To investigate the neural differentiation potential of human umbilical cord blood-derived AC133+ cells. DESIGN, TIME AND SETTING: Control experiments by grouping were performed in the Hematology Institute of Tianjin Hematology Hospital and Central Laboratory of Neurosurgery in Yuquan Hospital of Tsinghua University from August 2005 to December 2007.MATERIALS: Human umbilical cord blood was sampled from full-term newborn infant. Fetal brain-derived trophic support cells were harvested from aborted fetus of 22 weeks old.MAIN OUTCOME MEASURES: After the induction, human cord blood cells were collected at weeks 1, 2 and 4. RT-PCR was used to detect the expression of nestin, bone morphogenetic protein-2 and neural cell adhesion molecule. Immunocytochemistry method was applied to detect the cytotype-specific antigen. RESULTS: In the culture medium containing epidermal growth factor and basic fibroblast growth factor, human cord blood AC133+ cells could express nestin and bone morphogenetic protein-2, which were down-regulated even closed up in suboptimal condition. In the DMEM/F12 medium supplemented with epidermal growth factor, basic fibroblast growth factor and brain-derived neurotrophic factor, the gene expression of bone morphogenetic protein-2 and nestin continued in optimal condition at 2 weeks. Moreover neural cell adhesion molecule, another gene of neural cells, also expressed in this condition. AC133+ cells co-cultured with fetal brain-derived trophic support cells exhibited similar expressions. In the optimal non-cell-cell contact co-culture system, glial fibrillary acidic protein-positive cells were found by immuocytochemistry, while neuronal marker β-tubulin Ⅲwas expressed in the cell-cell direct contact system. These outcomes indicated that human cord blood isolated AC133+ cells may have an effect through gene rearrangement on inducing stem cells to express nerve cell development factors.CONCLUSION: The human umbilical cord blood-derived AC133+ cells contain some multipotential stem cells with differentiation potential, neural differentiation-related antigen when exposed to a suitable microenvironment.

Objective To observe the effect of γ-ray irradiation on CD4 + CD25 + regulatory T cells (Tregs),and to investigate the mechanism of immune injury induced by irradiation.Methods The thymus and spleen of C57BL/6 mice were taken and weighted 1-28 d after γ-ray irradiation,and the organ coefficients were calculated.The amount of mouse peripheral WBC measured,CD4 + T cells and Tregs in peripheral and splenic were analyzed by flow cytometry.Results Coefficients of mouse thymus and spleen decreased significantly 1 d post irradiation,and reached to the bottom at 7 d.Coefficients did not recover to control level 28 d after radiation.Peripheral WBC continuously decreased and reached the bottom at 7 d,and did not recover to control level up to 28 d postirradiation.Peripheral CD4 + T lymphocyte temporally reduced at 1 d,while it increased at 7 d,and it approached to control level at 28 d after radiation.Splenic CD4 + T cells slightly reduced at 7 d however,they basically maintained as the same level as control 14 d and 28 d after radiation.Peripheral Tregs ascended at 1 d and reached the peak at 7 d,and reduced at 14 d and 28 d postirradiation,although they still were significantly higher than those of control group.At the same time,splenic Tregs increased significantly and achieved peak value at 1 d,and then gradually decreased and reached the minimum at 28 d after irradiation,which were significantly lower than those of control group( t =2.731,P ＜ 0.05).Conclusions Mouse thymus and spleen were injured severely,and the number of immunocytes decreased after 6 Gy whole body γ-ray irradiation.However,Tregs with immunosuppressive action increased significantly postirradiation,revealing that Tregs were closely correlated with immune function depression and immunomodulation imbalance induced by ionizing radiation.