AIM: To study the effect of streptozotoxin-induced diabetes on cAMP-mediated dilation of rat small coronary arteries (RSCA). METHODS: The diabetes models were induced by injection of streptozotoxin (STZ) to tail vein. The dilation of RSCA was examined by videomicroscopy measurement. RESULTS: (1) STZ diabetes reduced dilation induced by isoproterenol (ISO), operating through cAMP mechanism, in RSCA. This response was in a dose-dependent manner and endothelium-independent relation. (2) STZ diabetes reduced response of RSCA to adenylyl cyclase agonist forskolin and to adenylyl cyclase inhibitor SQ 22536. (3) The 4-aminopyridine, a Kv channel blocker of vascular smooth muscle, suppressed the dilation induced by ISO and forskolin in RSCA of STZ diabetes. (4) The NaF, a G-protein stimulator, reduced the response in RSCA of STZ diabetes. CONCLUSIONS: Although it is known that diabetes impairs endothelium-dependent vasodilation, the effect of diabetes on dilation mechanism independent of endothelium is not well understood. In the present study, it is demonstrated that dilation is reduced in STZ rat small coronary arteries via cAMP signal mechanism and Kv channel of vascular smooth muscle. The G-protein is able to influence this dilation mechanism.

Adult Clonorchis sinensis not only occurs in human hepatic duct,but also in the liver,gallbladder and bile ducts of animals,including dogs and cats,thus causing clonorchiasis—one of important parasitic zoonoses. In present study,we dis?sected a domestic cat in which a total of 736 pieces of trematodes,identified as Clonorchis sinensis,were detected in the liver and cholecyst. The findings indicate that Clonorchis sinensis may be endemic in domestic animals in Wuhu area,and observe our awareness in prevention of the parasites in house pets.

Objective To report the seizure of Laelaps echidninus on the surface of Apodemus agrarius in Wuhu area for the first time,which prompts that there may exist the spread of the diseases by mites. Methods The mites got from the rats poi-soned by bait were made as the routine slide specimen and then identified with the reference of previous literature. Results The mites seized from Apodemus agrarius were 8 female ones totally and identified as Laelaps echidninus. Conclusion There exsits Laelaps echidninus parasitic on the body of Apodemus agrarius in Wuhu area,which should be paid attention to seriously in order to prevent the spread of diseases by it.

Objective To separate and identify Thyreophagus entomophagus from beer yeast powder and observe its morpho?logical characteristics. Methods The beer yeast powder was collected from the scum after fermentation of the beer material, the mites in it were separated and made into slide specimens,and then they were identified and observed for the morphological characteristics under an optical microscope. Results The mites separated from the beer yeast powder were identified as female Thyreophagus entomophagus. Under the optical microscope,the bodies of the mites were long and narrow,which showed an oval shape,the gnathosoma was wide,the epidermis was colorless but lustrous,the external vertical seta,internal scapular seta,in?ner humerals,anterior lateral seta,and dorsal body setae were all absent,the bristles on the back of the body were relatively long,and all the feet were thick and strong. Conclusion Thyreophagus entomophagus can breed in the beer yeast powder,and therefore,the powder should be stored properly to avoid the contamination caused by the mites.

Objective To explore the effects of TNF-? on the function of Leydig cells, in order to elucidate the possible mechanisms involved. Methods Highly pure primary Leydig cells were obtained by Percoll discontinuous density gradient method. HE stain was used to observe the morphology of the cultured cells. The Leydig cells were treated with different doses of rat TNF-? (0.1, 1, 10, 100 ng/ml) for 48h, and then the supernatants of culture medium were collected every 24 hours at the 1st, 2nd, 3rd and 4th day. The testosterone level in the supernatant was measured by radioimmunoassay. The proliferation and TNF-?-induced apoptosis of Leydig cells were examined by MTT assay, flow cytometry (FCM) as well as acridine orange (AO) stain. Results The purity of Leydig cells was 70%-80% after purification with Percoll discontinuous density gradient method. The Leydig cells were rich in cytoplasm, which contained some secretory granules and round nucleus. After TNF-? treatment in different concentrations (0.1, 1, 10, 100ng/ml) for 24h, the inhibition rates of TNF-? on testosterone secretion of Leydig cells were 22.0%, 35.0%, 53.0% and 74.8%, respectively, and the decrease showed a time-dependent manner, but no statistically significant difference was found in each group at every time point except for 100ng/ml group. High concentration of TNF-? (10 and 100 ng/ml) could inhibit the proliferation and promote apoptosis of Laydig cells. Compared to control group, the inhibition rate and apoptosis rate in 10ng/ml and 100ng/ml group showed significant difference (respectively 38.4%?4.1%, 76.4%?8.7% and 13.2%?1.1%, 26.4%?5.8%). In addition, significant apoptosis could be seen in the high concentration groups as shown with AO staining. Conclusion The present study suggests that TNF-? can inhibit the basal testosterone secretion of Leydig cells, which might be related to the inhibition and apopotosis-induced effects of high concentration of TNF-?.

Objective To investigate the influence of composite transplantation of two kinds of acellular xeno-dermis (pigskin) and micro-autograft on wound healing. Methods Seventy-two Sprague-Dawley rats with full-thickness skin defect on the back were randomly divided into three groups, and then compositt skin I(acellular dermal xeno-matrix+autologous particulate skin +selective acellular xeno-dermis) was adopted to cover the skin defect in the experimental group I, composite skin II(acellular dermal xeno-matrix+autologous particulate skin + glutaraldehyde xeno-skin) was adopted to cover the skin defect in the experimental group II, and auto-particulate skin was adopted in the control group. The area of wound healing and the rates of wound contraction were calculated.Tissue samples were harvested and examined by means of histology, immunohistochemistry and electron microscopy. Results There were continuous epidermis and basement membrane, and the dermal matrix was a kind of matrix with normal structure and organization of collagen and without any cellular components in selective acellular xeno-dermis. There was full differentiation of epithelium, orderly collagen arrange and basal membrane of the skin could be identified by immunohistochemical stain in compound skin grafting group I. The healing effect of compound skin grafting group I was better than compound skin grafting group II and auto-particulate skin grafting group. Conclusion The composite grafts constructed by selective acellular xeno-dermis (pigskin) could be a potential new type of composite skin substitute for the repair of full-thickness skin defect.

Objective To compare the difference of wound healing quality of composite skin grafting consisting of xenogeneic (porcine) acellular dermal matrix (PADM) combined with micro-autograft or split-thickness autograft of skin. Methods Seventy-two Sprague-Dawley rats with full-thickness skin defect on the back were randomly divided into three groups,namely test group I with PADM with split-thickness autologous skin,test group II with HADM with autologous micro- skin and allogeneic skin graft,and control group with autologous micro-skin with allogeneic skin graft to cover the skin defect area respectively. The take rate and the condition of wound healing,and also the rates of wound contraction were calculated. Tissue samples were harvested for histological examination. Results The wound contraction was less in test group I and II than that in control group( P

OBJECTIVE To explore production of ?-lactamase induced by antibiotics in Pseudomonas aeruginosa biofilm and planktonic bacteria.METHODS In vitro models of P.aeruginosa biofilm were built up.The planktonic bacteria and P.aeruginosa biofilms were exposed to different concentrations of imipenem and ceftazidime.The quantitative analysis of ?-lactamase was undertaken.The class of ?-lactamase was verified by modified cefoxitin three-dimensional test.RESULTS Both P.aeruginosa biofilm and planktonic bacteria showed significant ?-lactamase activity in the presence of antibiotics.The maximal ?-lactamase activities of both were significantly different with the statistic method of test(P

Objective:To study the feasibility of 3-D reconstruction model in the observation of tetrachlorodibenzo-p-dioxin(TCDD) effected palatal organ development of fetal mouse.Methods:Kunming mice treated 40 ug/kg TCDD by lavage on day 12.5 of pregnancy were used as in the experimental group,isodose corn oil treated in the control group.On day 13.5,14.5 and 15.5 of pregnancy heads of the fetal mice were taken out and fixed.Conventional paraffin serial sections of palatal organ were preparated and dyed by hematoxylin-eosin,images of the palatal organs were collected and photoshop treated,3-D reconstruction of the palatal organ was performed by 3D-DOCTOR software.Results:3-D reconstruction images showed that palatal organs moved from on both sides above the tongue and gradually closed and merged in the control group.In the experimental group,the palatal organs moved from on both sides above the tongue was later than control group,gradually closed,but not merged,formed cleft palate.Conclusion:3D-DOCTOR software reconstruction can be used for the study of the development process effected by TCDD in the pregnant mouse.

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