OBJECTIVE:To observe the protective effect of naloxone on ischemical reperfusion injury in rat brain. METHODS: 36 Wistar rats were randomly divided into 3 groups(n=12): normal control group,model control group (normal saline) and naloxone group (naloxone 0.4 mg?kg-1). The model control group and the naloxone group were established into ischemical reperfusion injury model by a drain method of carotid artery. The naloxone was administered at the beginning of ischemia and reperfusion,respectively. At 120 min of reperfusion,the neuron morphous was observed under light microscope and electronic microscope,respectively,the width of the bright bands of the area surrounding neuron and blood vessels and the average density and gray scale value of Bax mRNA positive cells were detected. RESULTS: In naloxone group compared with model control group,the cellular morphous of the neurons was more integrated,the bright bands of the area surrounding neuron and blood vessels were narrower,the average density was lower while the gray scale value was higher for Bax mRNA positive cells and the expression of which was attenuated. CONCLUSION: The protective effect of naloxone on cerebral ischemia reperfusion injury in rat might be associated to the down-regulation of Bax mRNA expression of apoptotic cells.

Objective To explore the role of Bc1\|2,Bc1\|x1 and Bax during the process of Ginsenoside Rg1 protecting against apoptosis of substantia nigra neurons in Parkinson disease(PD) mouse model. Methods C57BL mice were administrated i.p. with MPTP to produce PD mouse model.And different doses of Rg1(2 5,5 0,10 0?mg/kg) were given i.p. prior 3 days to MPTP in preventive groups.Nissl staining,tyrosine hydroxythase(TH) immunostaining and TUNEL staining were used to observe the changes of nigra neurons.Bc1\|2,Bc1\|x1 and Bax immunostaining were used to detect the expression of these proteins. Results Pretreatment with Rg1(5 0,10 0?mg/kg) could prevent the loss of Nissl staining neurons and TH\|positive neurons,and decrease TUNEL\|staining ratio.Rg1 could enhance the expression level of Bc1\|2 and Bc1\|x1,and reduce the expression level of Bax. Conclusion\ Rg1 has protective effect on apoptosis of substantia nigra neurons in PD mouse model.The increased expression level of Bc1\|2 and Bc1\|x1,and the decreased expression level of Bax may be the important mechanism during Rg1 protection against apoptosis.

Objective To study the hypoglycemic effect and mechanism of n￣butyl alcohol extraction from Anoectochilus roxburghii. Methods The total of 12 normal rats were used as normal control group, and 48 diabetic model rats were divided into model control group, and high dose, middle dose and low dose treatment groups with 12 rats in each group,three treatment groups received Anoectochilus roxburghii at dose 600,400,200 mg.kg-1 , respectively, normal control group and model control group were administered with equal volume of 0.9% sodium chlorade solution once a day.After 21 days of drug administration, the weights of rats, the levels of blood glucose and insulin were examined. Results Compared with normal control group, the body weight in model control group decreased significantly(P<0.01), while blood glucose significantly increased (P<0.01).Compared with model control group, the body weight in Anoectochilus roxburghii groups exhibited no obvious difference,while blood glucose decreased significantly (P<0.01 or P<0.05).The level of insulin in high dose group increased remarkably (P<0.05). Conclusion The n￣butyl alcohol extraction from Anoectochilus roxburghii shows markedly hypoglycemic effect,specifically for which at high dose increases the level of insulin significantly,its mechanism may involve with promoting β cells regeneration.

The developing process of thermal comfort was analyzed based on physiology and psychology and the relationship between thermal comfort and human health, environment was discussed in this paper.It suggested that the thermo-stable and thermo-comfortable environment, which might decrease body's adaptability to environment, were not necessarily good for human health. It might have some impacts on human's physiological and psychological adaptabilities also to live in the environment with a great difference between the indoor and outside temperature simultaneously and alternately.

With the acceleration of the aging process of the population, the number of patients suffering from dementia has increased year by year, which has become a prominent social public health problem and has brought a huge burden to the global economy. The effective intervention of controllable risk factors for dementia can reduce and delay the occurrence of dementia by 40%. Strengthening the intervention of the controllable risk factors of dementia, promoting the early diagnosis of dementia, improving the whole-process management of dementia treatment, and exploring new therapeutic targets are a huge systematic project that urgently needs the joint efforts of individuals and the public health system.

Objective Through analyzing the status quo of mental health service in Hunan province in 2002 to put forward policy suggestions for health management department. Methods Applying descriptive methods to analyze the status quo of mental health service. Results Mental health resources in Hunan province was insufficient and the utilization of health resources was low. Conclusions Setting up mental health management section; Increasing the funds for health service; Strengthening the training of professionals; exploiting the service field of related specialities and developing community mental health.

Objective To investigate the effects of IGFBP-3,RXR? and STAT-1 on A?_ 1-42 induced apoptosis in rat hippocampus neurons.Methods Apoptosis was induced by fibrillar A?_ 1-42.The percentage of neurons apoptosis was evaluated by microscopy after staining with TUNEL/DAPI.IGFBP-3 and RXR? positive neurons were observed by immunofluorescence.The expression of RXR? and STAT-1 protein were detected by Western blotting.Results After treatment with 20?mol/L A?_ 1-42 for 24 hours,the apoptotic hippocampus neurons were shown by TUNEL/DAPI assay.The percentage of apoptotic neurons was increased in a time-dependent manner.During the development of apoptosis,both the percentage of IGFBP-3/RXR? positive neurons and the expression of RXR? protein increased markedly after 3-6hours(P

BACKGROUND: The presence of various microorganisms in dental unit waterlines has been revealed by numerous reports previously. However, impact of different dental procedures on microbial contamination in dental unit waterlines (DUWLs) remains unclearly.OBJECTIVE: To assess the level of microbial contamination in water effluent from the high-speed handpiece line of dental chair units (DCUs) among different specialty departments in a provincial stomatological hospital. Thus, to propose individual infection control measures for different specialty departments according to their properties of microbial contamination.DESIGN, TIME AND SETTING: A cross-sectional investigation was designed and conducted in Guangdong Provincial Stomatological Hospital and Laboratory of Microbiology, School of Public Health and Tropical Medicine, Southern Medical University, between May 2007 and March 2008.MATERIALS: The materials used in this investigation including nutrient agar, blood plates, biochemical testing kit, agglutination testing kit and Gram staining agents. These materials were purchased from Guangdong Huankai Microbial Science and Technology Co., Ltd.METHODS: Water sampling was conducted at 80 DCUs of different specialty departments in Guangdong Provincial Stomatological Hospital. A total of 60 mL, with 6 mL for once sampling of water effluent from the high-speed handpiece line of each DCU were collected aseptically after the finish of the daily clinical work on every second Friday between May and October in 2007. Standard isolation and identification technique of bacteria was adopted.MAIN OUTCOME MEASURES: Concentration of bacteria and prevalence of 3 species of bacteria in water effluent from the high-speed handpiece line of DCUs among different specialty departments were evaluated.RESULTS: Concentration of bacteria in water effluent from the high-speed handpiece line of DCUs averaged 5.67×10~2 cfu/mL, ranged from 5.15×10 to 1.59×10~3 cfu/mL. The microbial concentration of water samples from Department of Periodontics was significantly higher than that from other departments, while the microbial concentration of water samples from Department of Oral Surgery was the lowest (P = 0.000).CONCLUSION: Contamination in water effluent from the high-speed handpiece line of DCUs varied from different specialty departments in the provincial stomatological hospital. It is suggested that DUWLs flushing should be performed routinely, especially for the department without frequent use of the high-speed handpiece in the daily work, and extra infection control measures should be adopted for the department with severe clinical operative contamination.

BACKGROUND:Daily flushing of dental unit waterlines (DUWLs) is believed to be the least expensive and simplest method for reducing the level of microbial contamination in DUWLs.Authorities' guidelines suggest that high-speed handpieces should be run to discharge water for 30 seconds after use on each patient.However,the guideline is inaccurate for clinicians according to the time-dependent flushing since the maximum flow rate of flushing water varied from dental chair units (DCUs).OBJECTIVE:To assess the level of microbial contamination in water effluent from the air-water syringe and the high-speed handpiece line of DCUs and prevalence of three species of bacteria detected in DUWLs at each flushing volume.Thus,practical water flushing measures could be proposed according to the effect of volume-dependent dental unit waterline flushing on the microbial contamination in DUWLs.DESIGN,TIME AND SETTING:A cross-sectional investigation was designed and conducted in Guangdong Provincial Stomatological Hospital and Laboratory of Microbiology,School of Public Health and Tropical Medicine,Southern Medical University between May 2007 and March 2008.MATERIALS:The materials used in this investigation including nutrient agar,blood plates,biochemical testing kit,agglutination testing kit and Gram staining agents.These materials were supported by Guangdong Huankai Microbiological Science and Technology Ltd.METHODS:Water sampling was conducted at 80 DCUs in a stomatologicel hospital.A total of 6 mL,2 mL for once sampling,of continuous water flushing from the air-water syringe and the high-speed handpiece line of each DCU respectively were collected aseptically after the finish of the daily clinical work on every second Friday,between May 2007 and October 2007.Standard isolation and identification technique of bacteria was adopted.MAIN OUTCOME MEASURES:Concentration of bacteria and prevalence of three species of bacteria in water effluent from the air-water syringe and the high-speed handpiece line of DCUs at each flushing volume were evaluated.RESULTS:The median concentration of bacteria in water effluent from either the air-water syringe or the high-speed handpiece line of DCUs was 5.67×10~2 cfu/mL,and there were no statistical differences among microbial concentrations of first three 2-mL flushing water samples (P>0.05).Prevalence of Staphylococcus spp.from the third 2-mL flushing water sample demonstrated an obviously higher level than that of Staphylococcus spp.from the first two 2-mL (P < 0.05),while prevalence of Streptococcus spp.and Actinomycete spp.kept at a relative stable level (P > 0.05) at each flushing volume.CONCLUSION:Volume-dependent water flushing procedure stays a more practical measure for reducing microbial contamination in DUWLs rather than time-dependent flushing,but the volume of flushing water needs to be further evaluated.

BACKGROUND: Transplantation of bone marrow mesenchymal stem cells (MSCs) improves functional recovery after spinal cord injury (SCl), but the mechanisms involved remain unclear.OBJECTIVE: To observe the effects of MSCs transplantation on the expression of brain-derived neurotrophic factors (BDNF) in rats after SCl.DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment. The study was performed at the Laboratory of Neuroanatomy, China Medical University from April to July 2003.MATERIALS: A total of 64 SD rats, aged 3 months, of either gender, weighing 250-300 g, were used. Of them, 4 were randomly selected to isolate and culture MSCs, and the remaining were used to establish SCl models.METHODS: The 60 rats were randomly divided into 3 groups. Seven days after SCl, MSCs group (n=24) was transplanted with 5 μL culture solution containing 1×109/L MSCs to the injury site using micro-injection; PBS group (n=24) was transplanted with 5μ L PBS, and the blank control group (n=12) with 5μ L normal saline.MAIN OUTCOME MEASURES: The rats were sacrificed at 7, 14, and 28 days post-surgery. MSCs morphology was observed and the expression of BDNF at the lesion areas was examined by immunohistochemistry,RESULTS: All 60 rats were included in the final analysis. After ten subcultures, the cell proliferative capacity was reduced, and cell body turned to flat; the MSCs protiferation and morphous could be maintained by adding basic fibroblast growth factor.Transplantation of MSCs enhanced the expression of BDNF compared with PBS and blank control groups at 7, 14, and 28 days post-surgery (P ＜ 0.05); white no significant difference was found between PBS and blank control groups (P ＞ 0.05).