<abstract>Aim: To investigate the ultrastructural changes of penile corpus cavernosum and tunica albuginea in rats treated with castration or finasteride. Methods: Eighteen male Sprague-Dawley rats of nine weeks...<abstract>Aim: To investigate the ultrastructural changes of penile corpus cavernosum and tunica albuginea in rats treated with castration or finasteride. Methods: Eighteen male Sprague-Dawley rats of nine weeks old were randomly divided into three groups with 6 rats each. Group A served as the control, Group B was castrated and Group C, treated with finasteride. Four weeks later, rats were anesthetized and blood samples obtained for the determination of serum testosterone (T) and dihydrotestosterone (DHT) levels; penile tissues were taken for scanning electron microscopy. Results: The T, free T and DHT levels in Group B and the DHT level in Group C were significantly lower than those in Group A (P<0.05). The tunica albuginea was significantly thinner in Group B than that in Group A (P<0.05), but there was no significant difference between Group C and Group A (P>0.05). Elastic fibers in the tunica albuginea of Group A were very rich and arranged regularly and undulatedly, but in Group B, most of the elastic fibers were replaced by collagenous fibers. In Group C, the tunica albuginea was mainly composed of thick and irregular-arranged collagenous fibers. In Group A, there were abundant smooth muscle fibers in the trabeculae of corpus cavernosum, but they were much less in Group C and scarce or even disappeared in Group B. In Groups B and C, the diminished/disappeared smooth muscle fibers were replaced by irregularly arranged collagenous fibers. Conclusion: In rats, androgen is essential for maintaining the normal structure of penile tunica albuginea and corpus carvenosum.展开更多
AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.M...AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.METHODS: Islet-like cell clusters (ICCs) were isolated from human fetal pancreas by using collagenase digestion. The free-floating ICCs were handpicked and cultured in a new dish. After the ICCs developed into monolayer epithelium-like cells, they were passaged and induced for differentiation. Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence stain, fluorescenceactivated cell sorting (FACS) and radioimmunoassay (RIA)were used to detect the expression of cell markers. RESULTS: (1) The monolayer epithelium-like cells had highly proliferative potential and could be passaged more than 16 timesin vitro; (2) RT-PCR analysis and immunofluorescence stain showed that these cells expressed both nestin and ABCG2, two of stem cellmarkers; (3) FACS analysis revealed that CD44, CD90and CD147 were positive, whereas CD34, CD38, CD45, CD71, CD117, CD133 and HLA-DR were negative on the nestin-positive cells; (4) RT-PCR analysis showed that the mRNA expression of insulin, glucagon and pancreaticduodenal homeobox gene-1 was detected, whereas the expression of nestin and neurogenin 3 disappeared in these cells treated with serum-free media supplemented with the cocktail of growth factors. Furthermore, the intracellular insulin content was detected by RIA after the induction culture.CONCLUSION: Nestin-positive cells isolated from human fetal pancreas possess the characteristics of pancreatic progenitor cells since they have highly proliferative potential and the capability of differentiation into insulinproducing cells in vitro. Interestingly, the nestin-positive pancreatic progenitor cells share many phenotypic markers with mesenchymal stem cells derived from bone marrow.展开更多
TO evaluate the association between obesity and colorectal cancer risk. METHODS： We searched PubMed, EMBASE, and the Cochrane Library up to January 1, 2007. Cohort studies permitting the assessment of causal associat...TO evaluate the association between obesity and colorectal cancer risk. METHODS： We searched PubMed, EMBASE, and the Cochrane Library up to January 1, 2007. Cohort studies permitting the assessment of causal association between obesity and colorectal cancer, with clear definition of obesity and well-defined outcome of colorectal cancer were eligible. Study design, sample size at baseline, mean follow-up time, co-activators and study results were extracted. Pooled standardized effect sizes were calculated.展开更多
Aim: To clarify the ultrastructural changes of penile tunica albuginea (TA) in streptozotocin (STZ)-induced diabetic rats. Methods: Intraperitoneal injection of STZ was used to induce diabetes mellitus (DM) in 12 Spra...Aim: To clarify the ultrastructural changes of penile tunica albuginea (TA) in streptozotocin (STZ)-induced diabetic rats. Methods: Intraperitoneal injection of STZ was used to induce diabetes mellitus (DM) in 12 Sprague Dawley rats. Ten rats (age and weight-matched) were used as control. Blood samples from the tail snips of the rats were used for the determination of serum glucose levels with SureStep Plus Blood Meter. At week 4 and 10 after the injection, half of the rats in each group were sacrificed and penile samples were obtained from the middle third of the penile shaft for the examination of TA under scanning electron microscopy. Results: In the diabetic group, the serum glucose levels were higher (P<0.01 at both time points) and the TA were thinner (P<0.05) than those of the controls. In the control group, the fibers of TA were rich and arranged regularly and undulated, while in the diabetic group, the fibers were diminished, lost the undulations and were arranged irregularly. Conclusion: In rats, DM appeared to impair the penile TA ultrastructures and this impairment could contribute to diabetic erectile dysfunction in part by impairing the veno-occlusive function.展开更多
AIM: To explore the influence of hepatic glucose production on acute insulin resistance induced by a lipid infusion in awake rats. METHODS: A hyperinsulinaemic-euglycaemic clamp was established in awake chronically ca...AIM: To explore the influence of hepatic glucose production on acute insulin resistance induced by a lipid infusion in awake rats. METHODS: A hyperinsulinaemic-euglycaemic clamp was established in awake chronically catheterized rats. Two groups of rats were studied either with a 4-h intraarterial infusion of lipid/heparin or saline. Insulin-mediated peripheral and hepatic glucose metabolism was assessed by hyperinsulinaemic-euglycaemic clamp combined with [3-^3H]-glucose infusion. RESULTS: During hyperinsulinaemic-euglycaemic clamp,there was a significant increase in plasma free fatty acid (FFA, from 741.9±50.6 to 2346.44±238.5μmol/L, P<0.01) in lipid-infused group. The glucose infusion rates (GIR) in the lipid infusion rats, compared to control rats, were significantly reduced (200-240 min average: lipid infusion; 12.64±1.5 vs control; 34.04±1.6 mg/kg.min, P<0.01), declining to - 35% of the corresponding control values during the last time of the clamp (240min: lipid infusion; 12.04±1.9 vs control; 34.74±1.7 mg/kg·min, P<0.0001). At the end of clamp study,the hepatic glucose production (HGP) in control rats was significantly suppressed (88%) from 19.04±4.5 (basal) to 2.34±0.9 mg/kg.min (P<0.01). The suppressive effect of insulin on HGP was significantly blunted in the lipid-infused rats (200-240 min: from 18.74±3.0 to 23.24±3.1 mg/kg.min (P<0.05). The rate of glucose disappearance (GRd) was a slight decrease in the lipid-infused rats compared with controls during the clamp.CONCLUSION: These data suggest that lipid infusion could induces suppression of hepatic glucose production, impairs the abilities of insulin to suppress lipolysis and mediate glucose utilization in peripheral tissue. Therefore, we conclude that lipid-infusion induces an acute insulin resistance in vivo.展开更多
AIM: To assess the effects of propranolol as compared with placebo on gastrointestinal hemorrhage and total mortality in cirrhotic patients by using meta analysis of 20 published randomized clinical trials.METHODS: A ...AIM: To assess the effects of propranolol as compared with placebo on gastrointestinal hemorrhage and total mortality in cirrhotic patients by using meta analysis of 20 published randomized clinical trials.METHODS: A meta analysis of published randomized clinical trials was designed. Published articles were selected for study based on a computerized MEDLINE and a manual search of the bibliographies of relevant articles. Data from 20 relevant studies fulfilling the inclusion criteria were retrieved by means of computerized and manual search.The reported data were extracted on the basis of the intention-to-treat principle, and treatment effects were measured as risk differences between propranolol and placebo. Pooled estimates were computed according to a random-effects model. We evaluated the pooled efficacy of propranolol on the risk of gastrointestinal hemorrhage and the total mortality.RESULTS: A total of 1 859 patients were included in 20trials, 931 in the propranolol groups and 928 as controls.Among the 652 patients with upper gastrointestinal tract hemorrhage, 261 patients were treated with propranolol,and 396 patients were treated with placebo or non-treated.Pooled risk differences of gastrointestinal hemorrhage were -18 % [95 % CI, -25 %, -10 %] in all trials, -11% [95 % CI,-21%, -1%] in primary prevention trials, and -25 %[95 %CI, -39 %, -10 %] in secondary prevention trials. A total of 440 patients died, 188 in propranolol groups and 252 in control groups. Pooled risk differences of total death were -7 %[95% CI, -12 %, -3 %] in all trials, -9 %[95 % CI, -18 %, -1%]in primary prevention trials, and -5 %[95 %CI, -9 %, -1%]in secondary prevention trials.CONCLUSION: Propranolol can markedly reduce the risks of both primary and recurrent gastrointestinal hemorrhage,and also the total mortality.展开更多
AIM:To explore the effect of diabetic duration and blood glucose level on insulin like growth factor 1(IGF-1) gene expression and serum IGF-1 level.METHODS: Diabetes was induced into Sprague Dawley rats by alloxan and...AIM:To explore the effect of diabetic duration and blood glucose level on insulin like growth factor 1(IGF-1) gene expression and serum IGF-1 level.METHODS: Diabetes was induced into Sprague Dawley rats by alloxan and then the rats were subdivided into different groups with varying blood glucose level and diabetic duration.The parameters were measured as follows:IGF-1 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR),IGF-1 peptide and serum IGF-1 concentration by enzymelinked immunosorbent assay (ELISA).RESULTS:During early diabetic stage (week 2),in comparison with normal control group (NC), IGF-1 mRNA(1.17±0.069 vs 0.79±0.048, P<0.001;1.17±0.069 vs 0.53±0.023, P<0.0005, respectively), IGF-1 peptide contents[(196.66±14.9)ng·mg^-1 vs(128.2±11.25)ng·mg^-1,P<0.0005;(196.66±14.9)ng·mg^-1 vs(74.43±5.33)ng·mg^-1, P<0.0001,respectively] were reduced in liver tissues of diabetic rats.The IGF-1 gene downregulation varied with glucose control level of the diabetic state,and deteriorated gradually further with duration of diabetes.By month 6, hepatic tissue IGF-1mRNA was 0.71±0.024 vs 1.12±0.056,P<0.001;0.47±0.021 vs 1.12±0.056, P<0.0005,respectively.IGF-1 peptide was (114.35±8.09) ng·mg^-1 vs (202.05±15.73)ng·mg^-1,P<0.0005; (64.58±3.89) ng·mg^-1 vs(202.05±15.73)ng·mg^-1,P<0.0001 respectively. Serum IGF-1 was also lowered in diabetic group with poor control of blood glucose.On week 2, serum IGF-1 concentrations were (371.0±12.5)ng·mg^-1 vs(511.2±24.7)ng·mg^-1,P<0.0005, (223.2±9.39)ng·mg^-1 vs(511.2±24.7)ng·mg^-1, P<0.0001 respectively. By month 6, (349.6±18.62)ng·mg^-1 vs(520.7±26.32)ng·mg^-1,P<0.0005, (188.5±17.35 vs520.7±26.32)ng·mg^-1,P<0.0001,respectively. Serum IGF-1 peptide change was significantly correlated with that in liver tissue (r=-0.99, P<0.001).Furthermore,No difference was found in the above parameters between diabetic rats with euglycemia and non-diabetic control group.CONCLUSION: The influence of diabetic status on IGF-1 gene expression in liver tissues is started from early diabetic stage, causing down regulation of IGF-1 expression,and progresses with the severity and duration of diabetic state.Accordingly serum IGF-1 level decreases. This might indicate that liver tissue IGF-1 gene expression is greatly affected in diabetes, thus contributing to reduction of serum IGF-1 level.展开更多
Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60d...Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminif-erous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereologicalmethods as a measure of the spermatogenic efficiency. Results: Low dose (8 mg/kg) TU treatment virtually hadno effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and se-vere suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of therecovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well toler-ated by animals. Conclusion: TU injection reversibly suppresses spermatogenesis in rats.展开更多
Aim: To study the androgen dependence of the neurotransmitter, calcitonin gene-related peptide (CGRP) in rat penis. Methods: Forty-four Sprague-Dawley rats were randomly divided into Group A (intact controls), Group B...Aim: To study the androgen dependence of the neurotransmitter, calcitonin gene-related peptide (CGRP) in rat penis. Methods: Forty-four Sprague-Dawley rats were randomly divided into Group A (intact controls), Group B (castrated) and Group C (gavaged with finasteride 4.5 mg·kg^(-1).day^(-1)). Four and ten weeks later respectively, half of rats in each group were anaesthetized. Blood samples were taken for the measurement of serum testosterone and dihydrotestosterone (DHT) by means of radioimmunoassay. Penile samples were harvested for the investigation of calcitonin gene related peptide (CGRP)-immunoreactive nerve fibers with immunohistochemistry. The computer-assisted imaging analysis system was applied to calculate the area proportion of the CGRP-positive nerve fibers (CGRP-PNF) in each group. Results: 1) Both 4 and 10 weeks later, testosterone and DHT levels in Group B decreased significantly compared with those in Group A, (P < 0.05, P < 0.01, respectively); DHT level in Group C was also significantly decreased in comparison with that in Group A for both 4- and 10- week animals (P < 0.05); 2) There was no significant differences in area proportion of CGRP-PNF among Groups A, B and C 4 weeks after treatments (P > 0.05); However, 10 weeks later, the proportion of CGRP-PNF in Groups B and C was significantly less than that in Group A (P < 0.01);3) The proportion of CGRP-PNF of 4-week animals in Groups B and C was significantly higher than that of 10-week animals (P < 0.05). Conclusion: The expression of neurotransmitter, CGRP may depend on androgens, including testosterone and DHT in rat penis.展开更多
Objective To analyze the clinical characteristics of nonfunctioning pheochromocytoma, and to evaluate the efficacy of 131I-metaiodobenzylguanidine (MIBG) scan in the diagnosis and perioperative treatment of nonfunctio...Objective To analyze the clinical characteristics of nonfunctioning pheochromocytoma, and to evaluate the efficacy of 131I-metaiodobenzylguanidine (MIBG) scan in the diagnosis and perioperative treatment of nonfunctioning pheochromocy- toma. Methods The clinical data of 14 patients with nonfunctioning pheochromocytoma were analyzed retrospectively. Plasma free corticoid, renin, aldosterone, and urine catecholamines levels were estimated. B-mode ultrasonography, computed tomo- graphy scan, thoracic X-ray and 131I-MIBG were used. Results All patients with nonfunctioning pheochromocytoma had no hypertension and the tumors were found inciden- tally. The 24 hours urine catecholamines levels in 80% (8/10) patients were normal. The positive rate of 131I-MIBG was 80% (8/10) and the specificity was 100%. All patients underwent surgical operation of tumor resection. No preoperative volume expansion was given to all patients. All tumors were resected completely, and no death accident happened. There was no recurrence and metastasis after operation by long-term follow-up. Conclusion 131I-MIBG scan is the first choice technique for the diagnosis of nonfunctioning pheochromocytoma. Blood volume expansion is unnecessary before resection of pheochromocytoma.no recurrence and metastasis})展开更多
Objective To evaluate the effects of acute glucose level changes on expression of prepro-orexin, orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) mRNA in rat hypothalamus tissue and pancreatic islets cells. Metho...Objective To evaluate the effects of acute glucose level changes on expression of prepro-orexin, orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) mRNA in rat hypothalamus tissue and pancreatic islets cells. Methods Thirty adult male Wistar rats were randomly divided into three equal groups (n = 10). The acute hypoglycemia rat model was induced by a single subcutaneous injection of insulin. Twenty acute hypoglycemia rats were divided into group B and group C. Group B was allowed to eat freely, while group C was food-deprived. Control rats were injected the same volume of saline. The effect of glucose levels (2.8 mmol/L and 8.3 mmol/L) on pancreatic islet cell orexin system was detected in pancreas islet cell cultured in vitro. The expression of prepro-orexin and OXR mRNA was examined in rat hypothalamus tissue and pancreatic islets cell cultured in vitro using reverse transcription-polymerase chain reaction (RT-PCR). Results Expression of orexin mRNA increased about 150% for the food-deprived hypoglycemia rats in comparison with control group (P < 0.01), whereas expression of OX1R mRNA decreased up to 30% (P < 0.01). However, expression of OX2R mRNA was unchanged in comparison with control group. In vitro, after incubation with 2.8 mmol/L glucose for 6 hours, the expression of prepro-orexin mRNA increased 2 times in rat pancreas islet cells in comparison with 8.3 mmol/L glucose group (P < 0.01). But the expression of OX1R mRNA was not sensitive to acute glucose fluctuation.Conclusions Orexin in rat hypothalamus is stimulated by decline in blood glucose and inhibited by signals related to feeding. Moreover, glucose plays a role in modulating the gene expression of prepro-orexin in rat pancreatic islet cells.展开更多
This study aimed at acquiring knowledge on the hypoglycemic mechanisms of sodium metavanadate (SMV) showed that the liver glucokinase and muscle hexokinase activities increased rapidly after oral SMV was given, and th...This study aimed at acquiring knowledge on the hypoglycemic mechanisms of sodium metavanadate (SMV) showed that the liver glucokinase and muscle hexokinase activities increased rapidly after oral SMV was given, and that the blood glucose level was correlated closely with the activities of the two enzymes but not with the insulin level; which indicated that SMV could improve the altered glucose phosphorylation in diabetic mice independently of stimulating insulin secretion. This was probably one of the mechanisms of hypoglycemic effects of SMV.展开更多
To study the effects of XW630 on bone formation in overiectomized(OVX) rats and in human osteoblast like cell line TE85. [WT5”BX]Method.[WT5”BZ] Bone histomorphometric analysis was performed with undecalcified bone ...To study the effects of XW630 on bone formation in overiectomized(OVX) rats and in human osteoblast like cell line TE85. [WT5”BX]Method.[WT5”BZ] Bone histomorphometric analysis was performed with undecalcified bone sections and tetracycline intraperitoneally labeling. [WT5”BX]Results.[WT5”BZ] Compared with that of OVX rats, the static data of trabecular bone volume(TBV)/ total tissue volume(TTV), TBV/sponge bone volume(SBV) and mean trabecular plate density (MTPD) were enhanced while mean trabecular plate spacing(MTPS) decreased after treated with XW630 for 13w. The dynamic data of single labeled surface [Sfract(s)], double labeled surface[Sfract(d)],Sfract(d+1/2s),trabecular osteoid surface(TOS), and bone formation rate in tissue level (Svf) were increased and osteoid maturation period (OMP) shortened in XW630 group. In osteoblast like cells, both 3H thymidine incorporation and cell count increased after treated with XW630 for 48. Treated with XW630 for 12～18h,inducible nitric oxide synthase(iNOS) activity and cGMP content increased in time dependent manners. [WT5”BX]Conclusions.[WT5”BZ] XW630 enhanced bone activation frequency and increased trabecular connectivity, stability, and strength. The cellular mechanism related to effects of XW630 on bone formation in ovariectomized rats.展开更多
Objective: To investigate the effect of cytokines (TNF-α,IFN-γ and IL-6) on the expression of sodium-iodide symporter(NIS)gene in breast cancer cell(MCF-7). Methods:The breast cancer cell was cultureds with negativ...Objective: To investigate the effect of cytokines (TNF-α,IFN-γ and IL-6) on the expression of sodium-iodide symporter(NIS)gene in breast cancer cell(MCF-7). Methods:The breast cancer cell was cultureds with negative control culture or culture with different concentrations of cytokines for 72 h.NIS gene mRNA in breast cancer cells cultured was determined by reverse transcriptase-polymerase chain reaction(RT-PCR). Results:Expression of sodium-iodide symporter mRNA can be found decreasing along with increasing the concentration of cytokine dose-dependently. Conclusion: Cytokine may play a role in iodide-uptake modulating in breast cancer cells by their effect on NIS gene expression.展开更多
Objective To construct a single plasmid vector mediating doxycycline-inducible recombined human insulin gene expr-ession in myotube cell line. Methods An expression cassette of rtTAnls driven by promoter of human cyto...Objective To construct a single plasmid vector mediating doxycycline-inducible recombined human insulin gene expr-ession in myotube cell line. Methods An expression cassette of rtTAnls driven by promoter of human cytomegalovirus and a furin-cuttable recom-bined human insulin expression cassette driven by a reverse poly-tetO DNA motif were cloned into a single plasmid vector (prTR-tetO-mINS). The prTR-tetO-mINS and pLNCX were co-transfected into a myotube cell line (C2C12) and pLNCX vector were used as a control. After selection with G418, the transfected cells were induced with doxycycline at concentra-tions of 0, 2, and 10 μg/mL. RT-PCR was used to determine expression levels of recombinant insulin mRNA at the 5th day. Insulin production in cell cultures medium (at different incubation time) and cell extracts (at the 7th day) were analyzed with human pro/insulin RIA kits. Results Immune reactive insulin (IRI) level in cell medium was found increased at 24 hours of doxycycline incubation, and still increased at the 5th day. After withdrawn of doxycycline, IRI decreased sharply and was at baseline three days later. IRI and human insulin mRNA levels were positively related to different levels of doxycycline. A 25-fold increase in IRI was found against background expression at the 7th day. Conclusion Human insulin expression can be successfully regulated by doxycycline and the background was very low. This single tet-on insulin expression system may provide a new approach to a controlled insulin gene therapy in skeletal muscle.展开更多
The effects of intensive versus regular therapy on incidence and progress of microalbuminuria in type 2 diabetes were compared. During a follow-up of 3 years, 96 cases of diabetes mellitus were randomized to intensive...The effects of intensive versus regular therapy on incidence and progress of microalbuminuria in type 2 diabetes were compared. During a follow-up of 3 years, 96 cases of diabetes mellitus were randomized to intensive and regular therapy groups. HbA 1c goal was same in the two groups, but the goal of blood pressure (Bp) and lipid was more strict in the intensive therapy group than in the regular therapy group. There was statistically significant difference in the incidence and progression of vascular complications between the two groups. Logistic stepwise-regression analysis (odds ration, OR) showed that there was significant difference in the progression of nephropathy (OR 0.24, 95 % CI 0.12-0.76), retinopathy (OR 0.38, 95 % CI 0.16-0.88), peripheral neuropathy (OR 0.42, 95 % CI 0.22-0.86) and autonomic neuropathy (OR 0.29, 95 % CI 0.12-0.86) between the two groups (P<0.01). It was concluded that intensive blood glucose controlling could retard diabetic vascular complications. Intensive therapy of multiple factors interventions (controlling Bp, regulating blood lipid, improving microcirculation) could decrease various risk factors for diabetic vascular complications.展开更多
The effects of heparin on the expression of transforming growth factor-β 1 (TGF-β 1) and two extracellular matrix components laminin (LN) and fibronectin (FN) in diabetic rat glomeruli were investigated. Twent...The effects of heparin on the expression of transforming growth factor-β 1 (TGF-β 1) and two extracellular matrix components laminin (LN) and fibronectin (FN) in diabetic rat glomeruli were investigated. Twenty-six rats were randomly divided into control group (C, n=8), diabetic group (D, n=9), and diabetes+heparin group (DH, n=9). After 8-week therapy of heparin (200 U once daily by abdominal injection), TGF-β 1, LN and FN expression in glomeruli was detected by immunohistochemical method. The results showed that the expression levels of TGF-β 1, LN and FN were higher in group D than in group C. It was found that heparin could reduce 24-h urinary albumin excretion and inhibit overexpression of TGF-β 1, LN and FN in glomeruli of diabetic rats. It suggested that the inhibitory effect of heparin on diabetic glomerular sclerosis was at least partly related with the inhibition of TGF-β 1 expression.展开更多
文摘<abstract>Aim: To investigate the ultrastructural changes of penile corpus cavernosum and tunica albuginea in rats treated with castration or finasteride. Methods: Eighteen male Sprague-Dawley rats of nine weeks old were randomly divided into three groups with 6 rats each. Group A served as the control, Group B was castrated and Group C, treated with finasteride. Four weeks later, rats were anesthetized and blood samples obtained for the determination of serum testosterone (T) and dihydrotestosterone (DHT) levels; penile tissues were taken for scanning electron microscopy. Results: The T, free T and DHT levels in Group B and the DHT level in Group C were significantly lower than those in Group A (P<0.05). The tunica albuginea was significantly thinner in Group B than that in Group A (P<0.05), but there was no significant difference between Group C and Group A (P>0.05). Elastic fibers in the tunica albuginea of Group A were very rich and arranged regularly and undulatedly, but in Group B, most of the elastic fibers were replaced by collagenous fibers. In Group C, the tunica albuginea was mainly composed of thick and irregular-arranged collagenous fibers. In Group A, there were abundant smooth muscle fibers in the trabeculae of corpus cavernosum, but they were much less in Group C and scarce or even disappeared in Group B. In Groups B and C, the diminished/disappeared smooth muscle fibers were replaced by irregularly arranged collagenous fibers. Conclusion: In rats, androgen is essential for maintaining the normal structure of penile tunica albuginea and corpus carvenosum.
基金Supported by the National Natural Science Foundation of China,No. 30170443 Major State Basic Research Development Program of China, No. 2001CB510105 and "211" Project Foundation of Peking University
文摘AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.METHODS: Islet-like cell clusters (ICCs) were isolated from human fetal pancreas by using collagenase digestion. The free-floating ICCs were handpicked and cultured in a new dish. After the ICCs developed into monolayer epithelium-like cells, they were passaged and induced for differentiation. Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence stain, fluorescenceactivated cell sorting (FACS) and radioimmunoassay (RIA)were used to detect the expression of cell markers. RESULTS: (1) The monolayer epithelium-like cells had highly proliferative potential and could be passaged more than 16 timesin vitro; (2) RT-PCR analysis and immunofluorescence stain showed that these cells expressed both nestin and ABCG2, two of stem cellmarkers; (3) FACS analysis revealed that CD44, CD90and CD147 were positive, whereas CD34, CD38, CD45, CD71, CD117, CD133 and HLA-DR were negative on the nestin-positive cells; (4) RT-PCR analysis showed that the mRNA expression of insulin, glucagon and pancreaticduodenal homeobox gene-1 was detected, whereas the expression of nestin and neurogenin 3 disappeared in these cells treated with serum-free media supplemented with the cocktail of growth factors. Furthermore, the intracellular insulin content was detected by RIA after the induction culture.CONCLUSION: Nestin-positive cells isolated from human fetal pancreas possess the characteristics of pancreatic progenitor cells since they have highly proliferative potential and the capability of differentiation into insulinproducing cells in vitro. Interestingly, the nestin-positive pancreatic progenitor cells share many phenotypic markers with mesenchymal stem cells derived from bone marrow.
文摘TO evaluate the association between obesity and colorectal cancer risk. METHODS： We searched PubMed, EMBASE, and the Cochrane Library up to January 1, 2007. Cohort studies permitting the assessment of causal association between obesity and colorectal cancer, with clear definition of obesity and well-defined outcome of colorectal cancer were eligible. Study design, sample size at baseline, mean follow-up time, co-activators and study results were extracted. Pooled standardized effect sizes were calculated.
文摘Aim: To clarify the ultrastructural changes of penile tunica albuginea (TA) in streptozotocin (STZ)-induced diabetic rats. Methods: Intraperitoneal injection of STZ was used to induce diabetes mellitus (DM) in 12 Sprague Dawley rats. Ten rats (age and weight-matched) were used as control. Blood samples from the tail snips of the rats were used for the determination of serum glucose levels with SureStep Plus Blood Meter. At week 4 and 10 after the injection, half of the rats in each group were sacrificed and penile samples were obtained from the middle third of the penile shaft for the examination of TA under scanning electron microscopy. Results: In the diabetic group, the serum glucose levels were higher (P<0.01 at both time points) and the TA were thinner (P<0.05) than those of the controls. In the control group, the fibers of TA were rich and arranged regularly and undulated, while in the diabetic group, the fibers were diminished, lost the undulations and were arranged irregularly. Conclusion: In rats, DM appeared to impair the penile TA ultrastructures and this impairment could contribute to diabetic erectile dysfunction in part by impairing the veno-occlusive function.
基金Supported by the National Natural Science Foundation of China,No.30270631,No.30370671,Science Foundation of Chongqing Health Bureau.No.99-3002 and Applied Basic Research Foundation of Chongqing Science and Technology Committee,No.02-34 and Science Founda
文摘AIM: To explore the influence of hepatic glucose production on acute insulin resistance induced by a lipid infusion in awake rats. METHODS: A hyperinsulinaemic-euglycaemic clamp was established in awake chronically catheterized rats. Two groups of rats were studied either with a 4-h intraarterial infusion of lipid/heparin or saline. Insulin-mediated peripheral and hepatic glucose metabolism was assessed by hyperinsulinaemic-euglycaemic clamp combined with [3-^3H]-glucose infusion. RESULTS: During hyperinsulinaemic-euglycaemic clamp,there was a significant increase in plasma free fatty acid (FFA, from 741.9±50.6 to 2346.44±238.5μmol/L, P<0.01) in lipid-infused group. The glucose infusion rates (GIR) in the lipid infusion rats, compared to control rats, were significantly reduced (200-240 min average: lipid infusion; 12.64±1.5 vs control; 34.04±1.6 mg/kg.min, P<0.01), declining to - 35% of the corresponding control values during the last time of the clamp (240min: lipid infusion; 12.04±1.9 vs control; 34.74±1.7 mg/kg·min, P<0.0001). At the end of clamp study,the hepatic glucose production (HGP) in control rats was significantly suppressed (88%) from 19.04±4.5 (basal) to 2.34±0.9 mg/kg.min (P<0.01). The suppressive effect of insulin on HGP was significantly blunted in the lipid-infused rats (200-240 min: from 18.74±3.0 to 23.24±3.1 mg/kg.min (P<0.05). The rate of glucose disappearance (GRd) was a slight decrease in the lipid-infused rats compared with controls during the clamp.CONCLUSION: These data suggest that lipid infusion could induces suppression of hepatic glucose production, impairs the abilities of insulin to suppress lipolysis and mediate glucose utilization in peripheral tissue. Therefore, we conclude that lipid-infusion induces an acute insulin resistance in vivo.
基金the National Natural Science Foundation of China,No.19872074
文摘AIM: To assess the effects of propranolol as compared with placebo on gastrointestinal hemorrhage and total mortality in cirrhotic patients by using meta analysis of 20 published randomized clinical trials.METHODS: A meta analysis of published randomized clinical trials was designed. Published articles were selected for study based on a computerized MEDLINE and a manual search of the bibliographies of relevant articles. Data from 20 relevant studies fulfilling the inclusion criteria were retrieved by means of computerized and manual search.The reported data were extracted on the basis of the intention-to-treat principle, and treatment effects were measured as risk differences between propranolol and placebo. Pooled estimates were computed according to a random-effects model. We evaluated the pooled efficacy of propranolol on the risk of gastrointestinal hemorrhage and the total mortality.RESULTS: A total of 1 859 patients were included in 20trials, 931 in the propranolol groups and 928 as controls.Among the 652 patients with upper gastrointestinal tract hemorrhage, 261 patients were treated with propranolol,and 396 patients were treated with placebo or non-treated.Pooled risk differences of gastrointestinal hemorrhage were -18 % [95 % CI, -25 %, -10 %] in all trials, -11% [95 % CI,-21%, -1%] in primary prevention trials, and -25 %[95 %CI, -39 %, -10 %] in secondary prevention trials. A total of 440 patients died, 188 in propranolol groups and 252 in control groups. Pooled risk differences of total death were -7 %[95% CI, -12 %, -3 %] in all trials, -9 %[95 % CI, -18 %, -1%]in primary prevention trials, and -5 %[95 %CI, -9 %, -1%]in secondary prevention trials.CONCLUSION: Propranolol can markedly reduce the risks of both primary and recurrent gastrointestinal hemorrhage,and also the total mortality.
基金Supported by the National Natural Science Foundation of China,No.39770355
文摘AIM:To explore the effect of diabetic duration and blood glucose level on insulin like growth factor 1(IGF-1) gene expression and serum IGF-1 level.METHODS: Diabetes was induced into Sprague Dawley rats by alloxan and then the rats were subdivided into different groups with varying blood glucose level and diabetic duration.The parameters were measured as follows:IGF-1 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR),IGF-1 peptide and serum IGF-1 concentration by enzymelinked immunosorbent assay (ELISA).RESULTS:During early diabetic stage (week 2),in comparison with normal control group (NC), IGF-1 mRNA(1.17±0.069 vs 0.79±0.048, P<0.001;1.17±0.069 vs 0.53±0.023, P<0.0005, respectively), IGF-1 peptide contents[(196.66±14.9)ng·mg^-1 vs(128.2±11.25)ng·mg^-1,P<0.0005;(196.66±14.9)ng·mg^-1 vs(74.43±5.33)ng·mg^-1, P<0.0001,respectively] were reduced in liver tissues of diabetic rats.The IGF-1 gene downregulation varied with glucose control level of the diabetic state,and deteriorated gradually further with duration of diabetes.By month 6, hepatic tissue IGF-1mRNA was 0.71±0.024 vs 1.12±0.056,P<0.001;0.47±0.021 vs 1.12±0.056, P<0.0005,respectively.IGF-1 peptide was (114.35±8.09) ng·mg^-1 vs (202.05±15.73)ng·mg^-1,P<0.0005; (64.58±3.89) ng·mg^-1 vs(202.05±15.73)ng·mg^-1,P<0.0001 respectively. Serum IGF-1 was also lowered in diabetic group with poor control of blood glucose.On week 2, serum IGF-1 concentrations were (371.0±12.5)ng·mg^-1 vs(511.2±24.7)ng·mg^-1,P<0.0005, (223.2±9.39)ng·mg^-1 vs(511.2±24.7)ng·mg^-1, P<0.0001 respectively. By month 6, (349.6±18.62)ng·mg^-1 vs(520.7±26.32)ng·mg^-1,P<0.0005, (188.5±17.35 vs520.7±26.32)ng·mg^-1,P<0.0001,respectively. Serum IGF-1 peptide change was significantly correlated with that in liver tissue (r=-0.99, P<0.001).Furthermore,No difference was found in the above parameters between diabetic rats with euglycemia and non-diabetic control group.CONCLUSION: The influence of diabetic status on IGF-1 gene expression in liver tissues is started from early diabetic stage, causing down regulation of IGF-1 expression,and progresses with the severity and duration of diabetic state.Accordingly serum IGF-1 level decreases. This might indicate that liver tissue IGF-1 gene expression is greatly affected in diabetes, thus contributing to reduction of serum IGF-1 level.
基金Financially supported by a"9th five-year" National Key Grant of Science and Technology (Grant number:969040401),and by Sichuan Committee of Education.
文摘Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminif-erous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereologicalmethods as a measure of the spermatogenic efficiency. Results: Low dose (8 mg/kg) TU treatment virtually hadno effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and se-vere suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of therecovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well toler-ated by animals. Conclusion: TU injection reversibly suppresses spermatogenesis in rats.
文摘Aim: To study the androgen dependence of the neurotransmitter, calcitonin gene-related peptide (CGRP) in rat penis. Methods: Forty-four Sprague-Dawley rats were randomly divided into Group A (intact controls), Group B (castrated) and Group C (gavaged with finasteride 4.5 mg·kg^(-1).day^(-1)). Four and ten weeks later respectively, half of rats in each group were anaesthetized. Blood samples were taken for the measurement of serum testosterone and dihydrotestosterone (DHT) by means of radioimmunoassay. Penile samples were harvested for the investigation of calcitonin gene related peptide (CGRP)-immunoreactive nerve fibers with immunohistochemistry. The computer-assisted imaging analysis system was applied to calculate the area proportion of the CGRP-positive nerve fibers (CGRP-PNF) in each group. Results: 1) Both 4 and 10 weeks later, testosterone and DHT levels in Group B decreased significantly compared with those in Group A, (P < 0.05, P < 0.01, respectively); DHT level in Group C was also significantly decreased in comparison with that in Group A for both 4- and 10- week animals (P < 0.05); 2) There was no significant differences in area proportion of CGRP-PNF among Groups A, B and C 4 weeks after treatments (P > 0.05); However, 10 weeks later, the proportion of CGRP-PNF in Groups B and C was significantly less than that in Group A (P < 0.01);3) The proportion of CGRP-PNF of 4-week animals in Groups B and C was significantly higher than that of 10-week animals (P < 0.05). Conclusion: The expression of neurotransmitter, CGRP may depend on androgens, including testosterone and DHT in rat penis.
文摘Objective To analyze the clinical characteristics of nonfunctioning pheochromocytoma, and to evaluate the efficacy of 131I-metaiodobenzylguanidine (MIBG) scan in the diagnosis and perioperative treatment of nonfunctioning pheochromocy- toma. Methods The clinical data of 14 patients with nonfunctioning pheochromocytoma were analyzed retrospectively. Plasma free corticoid, renin, aldosterone, and urine catecholamines levels were estimated. B-mode ultrasonography, computed tomo- graphy scan, thoracic X-ray and 131I-MIBG were used. Results All patients with nonfunctioning pheochromocytoma had no hypertension and the tumors were found inciden- tally. The 24 hours urine catecholamines levels in 80% (8/10) patients were normal. The positive rate of 131I-MIBG was 80% (8/10) and the specificity was 100%. All patients underwent surgical operation of tumor resection. No preoperative volume expansion was given to all patients. All tumors were resected completely, and no death accident happened. There was no recurrence and metastasis after operation by long-term follow-up. Conclusion 131I-MIBG scan is the first choice technique for the diagnosis of nonfunctioning pheochromocytoma. Blood volume expansion is unnecessary before resection of pheochromocytoma.no recurrence and metastasis})
基金Supported by Important FinancialIssueof Shi-Wu Programming Key Problem in Liaoning Provinceand Financial Issue for Scientific Research in the Department of Education.
文摘Objective To evaluate the effects of acute glucose level changes on expression of prepro-orexin, orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) mRNA in rat hypothalamus tissue and pancreatic islets cells. Methods Thirty adult male Wistar rats were randomly divided into three equal groups (n = 10). The acute hypoglycemia rat model was induced by a single subcutaneous injection of insulin. Twenty acute hypoglycemia rats were divided into group B and group C. Group B was allowed to eat freely, while group C was food-deprived. Control rats were injected the same volume of saline. The effect of glucose levels (2.8 mmol/L and 8.3 mmol/L) on pancreatic islet cell orexin system was detected in pancreas islet cell cultured in vitro. The expression of prepro-orexin and OXR mRNA was examined in rat hypothalamus tissue and pancreatic islets cell cultured in vitro using reverse transcription-polymerase chain reaction (RT-PCR). Results Expression of orexin mRNA increased about 150% for the food-deprived hypoglycemia rats in comparison with control group (P < 0.01), whereas expression of OX1R mRNA decreased up to 30% (P < 0.01). However, expression of OX2R mRNA was unchanged in comparison with control group. In vitro, after incubation with 2.8 mmol/L glucose for 6 hours, the expression of prepro-orexin mRNA increased 2 times in rat pancreas islet cells in comparison with 8.3 mmol/L glucose group (P < 0.01). But the expression of OX1R mRNA was not sensitive to acute glucose fluctuation.Conclusions Orexin in rat hypothalamus is stimulated by decline in blood glucose and inhibited by signals related to feeding. Moreover, glucose plays a role in modulating the gene expression of prepro-orexin in rat pancreatic islet cells.
文摘This study aimed at acquiring knowledge on the hypoglycemic mechanisms of sodium metavanadate (SMV) showed that the liver glucokinase and muscle hexokinase activities increased rapidly after oral SMV was given, and that the blood glucose level was correlated closely with the activities of the two enzymes but not with the insulin level; which indicated that SMV could improve the altered glucose phosphorylation in diabetic mice independently of stimulating insulin secretion. This was probably one of the mechanisms of hypoglycemic effects of SMV.
基金This project was supported by the National Natural ScienceFoundation of ChinaNo.39430 120
文摘To study the effects of XW630 on bone formation in overiectomized(OVX) rats and in human osteoblast like cell line TE85. [WT5”BX]Method.[WT5”BZ] Bone histomorphometric analysis was performed with undecalcified bone sections and tetracycline intraperitoneally labeling. [WT5”BX]Results.[WT5”BZ] Compared with that of OVX rats, the static data of trabecular bone volume(TBV)/ total tissue volume(TTV), TBV/sponge bone volume(SBV) and mean trabecular plate density (MTPD) were enhanced while mean trabecular plate spacing(MTPS) decreased after treated with XW630 for 13w. The dynamic data of single labeled surface [Sfract(s)], double labeled surface[Sfract(d)],Sfract(d+1/2s),trabecular osteoid surface(TOS), and bone formation rate in tissue level (Svf) were increased and osteoid maturation period (OMP) shortened in XW630 group. In osteoblast like cells, both 3H thymidine incorporation and cell count increased after treated with XW630 for 48. Treated with XW630 for 12～18h,inducible nitric oxide synthase(iNOS) activity and cGMP content increased in time dependent manners. [WT5”BX]Conclusions.[WT5”BZ] XW630 enhanced bone activation frequency and increased trabecular connectivity, stability, and strength. The cellular mechanism related to effects of XW630 on bone formation in ovariectomized rats.
文摘Objective: To investigate the effect of cytokines (TNF-α,IFN-γ and IL-6) on the expression of sodium-iodide symporter(NIS)gene in breast cancer cell(MCF-7). Methods:The breast cancer cell was cultureds with negative control culture or culture with different concentrations of cytokines for 72 h.NIS gene mRNA in breast cancer cells cultured was determined by reverse transcriptase-polymerase chain reaction(RT-PCR). Results:Expression of sodium-iodide symporter mRNA can be found decreasing along with increasing the concentration of cytokine dose-dependently. Conclusion: Cytokine may play a role in iodide-uptake modulating in breast cancer cells by their effect on NIS gene expression.
基金Supported by a grant from the Educational Department of Liaoning Province (99022067).
文摘Objective To construct a single plasmid vector mediating doxycycline-inducible recombined human insulin gene expr-ession in myotube cell line. Methods An expression cassette of rtTAnls driven by promoter of human cytomegalovirus and a furin-cuttable recom-bined human insulin expression cassette driven by a reverse poly-tetO DNA motif were cloned into a single plasmid vector (prTR-tetO-mINS). The prTR-tetO-mINS and pLNCX were co-transfected into a myotube cell line (C2C12) and pLNCX vector were used as a control. After selection with G418, the transfected cells were induced with doxycycline at concentra-tions of 0, 2, and 10 μg/mL. RT-PCR was used to determine expression levels of recombinant insulin mRNA at the 5th day. Insulin production in cell cultures medium (at different incubation time) and cell extracts (at the 7th day) were analyzed with human pro/insulin RIA kits. Results Immune reactive insulin (IRI) level in cell medium was found increased at 24 hours of doxycycline incubation, and still increased at the 5th day. After withdrawn of doxycycline, IRI decreased sharply and was at baseline three days later. IRI and human insulin mRNA levels were positively related to different levels of doxycycline. A 25-fold increase in IRI was found against background expression at the 7th day. Conclusion Human insulin expression can be successfully regulated by doxycycline and the background was very low. This single tet-on insulin expression system may provide a new approach to a controlled insulin gene therapy in skeletal muscle.
基金This project was supported by grants from Science and Re-search Founction of the Ministry of Health ( No.96- 2 - 10 2 )and Hubei Provincial Natural SciencesFoundation ( No.96J0 77)
文摘The effects of intensive versus regular therapy on incidence and progress of microalbuminuria in type 2 diabetes were compared. During a follow-up of 3 years, 96 cases of diabetes mellitus were randomized to intensive and regular therapy groups. HbA 1c goal was same in the two groups, but the goal of blood pressure (Bp) and lipid was more strict in the intensive therapy group than in the regular therapy group. There was statistically significant difference in the incidence and progression of vascular complications between the two groups. Logistic stepwise-regression analysis (odds ration, OR) showed that there was significant difference in the progression of nephropathy (OR 0.24, 95 % CI 0.12-0.76), retinopathy (OR 0.38, 95 % CI 0.16-0.88), peripheral neuropathy (OR 0.42, 95 % CI 0.22-0.86) and autonomic neuropathy (OR 0.29, 95 % CI 0.12-0.86) between the two groups (P<0.01). It was concluded that intensive blood glucose controlling could retard diabetic vascular complications. Intensive therapy of multiple factors interventions (controlling Bp, regulating blood lipid, improving microcirculation) could decrease various risk factors for diabetic vascular complications.
文摘The effects of heparin on the expression of transforming growth factor-β 1 (TGF-β 1) and two extracellular matrix components laminin (LN) and fibronectin (FN) in diabetic rat glomeruli were investigated. Twenty-six rats were randomly divided into control group (C, n=8), diabetic group (D, n=9), and diabetes+heparin group (DH, n=9). After 8-week therapy of heparin (200 U once daily by abdominal injection), TGF-β 1, LN and FN expression in glomeruli was detected by immunohistochemical method. The results showed that the expression levels of TGF-β 1, LN and FN were higher in group D than in group C. It was found that heparin could reduce 24-h urinary albumin excretion and inhibit overexpression of TGF-β 1, LN and FN in glomeruli of diabetic rats. It suggested that the inhibitory effect of heparin on diabetic glomerular sclerosis was at least partly related with the inhibition of TGF-β 1 expression.
