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1.
Study on the neurotoxic effects of low-level lead exposure in rats   总被引:10,自引:0,他引:10  
Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.  相似文献   

2.
Objective: To explore the effects of cytomegalovirus (CMV) infection on rejection-related gene expression in the endothelial cells of renal transplantation recipients. Methods: Endothelial cells (ECs) were cultured and stimulated by a variety of factors: A, normal control group; B, inactivated human cytomegalovirus (HCMV) infection group; C, HCMV infection group; D, HCMV supematant infection group; and E, ganciclovir HCMV group. Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompability complex (MHC) class Ⅰ and class Ⅱ antigens was detected by flow cytometry (FCM) and immuno-histochemistry. Results: We found characteristic CMV-infected ECs in this study. There were no significant differences among groups A, B and D (P>0.05). Although the expression levels of ICAM-1 were not significantly different between groups C and E (P>0.05), the ICAM-1 expression in these two groups was significantly higher than that in group A (P<0.05). ICAM-1 expression was detected in groups C and E, while there was no expression in groups A, B and D. Furthermore, there was no significant difference of ICAM-1 mRNA expression between groups C and E (P>0.05). Human leucocyte antigen (HLA)-ABC expression was detected in all the groups, while HLA-DR expression was only detected in groups C and E. There were no significant dif-ferences of HLA-ABC and HLA-DR expression among groups A, B and D (P>0.05). However, the HLA-ABC and HLA-DR expression levels in groups C and D were higher than those of the remaining groups previously reported (P<0.05). Meanwhile, the HLA-ABC and HLA-DR expression levels in group E were lower than those of group C (P<0.05). Conclusion: CMV could up-regulate the expression levels of ICAM-1 and MHC antigens, which was closely related to allograft rejection.  相似文献   

3.
Objective: This study was aimed at evaluating and comparing the quality of life in patients who underwent laparo-scopic and open cholecystectomy for chronic cholecystolithiasis. Methods: The study included 25 patients with laparoscopic cholecystectomy (LC group) and 26 with open cholecystectomy (OC group). The quality of life was measured with the Gastrointestinal Quality of Life Index (GLQI) preoperatively, thereafter regularly at 2, 5, 10 and 16 weeks after the operation. Results: The mean preoperative overall GLQI scores were 112.5 and 110.3 in LC and OC group respectively (P>0.05). In the LC group, the mean overall GLQI score reduced slightly to 110.0 two weeks after the operation (P>0.05). The LC group showed significant improvement in overall score and in the aspects of symptomatology, emotional and physiological status from 5 to 16 weeks postoperatively. In the OC group, the GLQI score reduced to 102.0 two weeks after surgery (P<0.05). Significant reductions were shown in the aspects of symptomatology, physiological and social status. The GLQI scores returned to the preoperative level of 115.6 ten weeks after the operation (P>0.05). The patients experienced significant improvements of GLQI sixteen weeks after OC operation (P<0.01-0.05). Within the 10 postoperative weeks, the LC group had significantly higher GLQI scores than the OC group (P<0.05). Conclusions: LC can improve the quality of life postoperatively better and more rapidly than OC. The assessment of quality of life assessment is a valid method for measuring the effects of surgical treatment.  相似文献   

4.
Objective: This study was aimed at evaluating and comparing the quality of life in patients who underwent laparo-scopic and open cholecystectomy for chronic cholecystolithiasis. Methods: The study included 25 patients with laparoscopic cholecystectomy (LC group) and 26 with open cholecystectomy (OC group). The quality of life was measured with the Gastrointestinal Quality of Life Index (GLQI) preoperatively, thereafter regularly at 2, 5, 10 and 16 weeks after the operation. Results: The mean preoperative overall GLQI scores were 112.5 and 110.3 in LC and OC group respectively (P>0.05). In the LC group, the mean overall GLQI score reduced slightly to 110.0 two weeks after the operation (P>0.05). The LC group showed significant improvement in overall score and in the aspects of symptomatology, emotional and physiological status from 5 to 16 weeks postoperatively. In the OC group, the GLQI score reduced to 102.0 two weeks after surgery (P<0.05). Significant reductions were shown in the aspects of symptomatology, physiological and social status. The GLQI scores returned to the preoperative level of 115.6 ten weeks after the operation (P>0.05). The patients experienced significant improvements of GLQI sixteen weeks after OC operation (P<0.01-0.05). Within the 10 postoperative weeks, the LC group had significantly higher GLQI scores than the OC group (P<0.05). Conclusions: LC can improve the quality of life postoperatively better and more rapidly than OC. The assessment of quality of life assessment is a valid method for measuring the effects of surgical treatment.  相似文献   

5.
6.
Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.  相似文献   

7.
INTRODUCTIONChronicinfectionwithHBVaffectsmorethan250millionpeopleworldwide.Therearemorethan120millionchronicHBVcarriersinChina;appro-ximately10percentofthemremaininstateofchronichepatitisandhaveahighriskofdevelop-mentofcirrhosisandhepatocellularcarcinoma.ButthereisnoeffectivemethodtocontrolchronicHBVinfectionatpresent.Recentdataindicatedthatim-munotherapeuticstrategiesstimulatingbothcellularandhumoralimmuneresponsestoHBVantigensareessentialforcuringchronicHBVinfection(ChisariandFe…  相似文献   

8.
9.
Accumulating evidence indicates that endostatin inhibits fibrosis. However, the mechanism is yet to be clarified. The aim of this study is to evaluate the effect of endostatin on platelet-derived growth factor-BB (PDGF-BB)-or transforming growth factor β1 (TGF-β1)-induced fibrosis in cultured human skin fibroblasts, and to further examine the molecular mechanisms involved. Human dermal fibroblasts were cultured in Dulbecco’s modified Eagle’s medium (DMEM) and serum-starved for 48 h before treatment. Cells were grouped as follows: “PDGF-BB”, “PDGF-BB+ endostatin”, “TGF-β1”, “TGF-β1+endostatin”, “endostatin”, and “blank control”. The fibroblasts were stimulated with either TGF-β1 or PDGF-BB for 72 h in order to set up the fibrosis model in vitro. The cells were co-cultured with either TGF-β1 or PDGF-BB and endostatin and were used to check the inhibiting effect of endostatin. A blank control group and an endostatin group were used as negative control groups. The biomarkers of fibrosis, including the expression of collagen I, hydroxyproline, and α-smooth muscle actin (α-SMA), were evaluated using an enzyme-linked immunosorbent assay (ELISA) and Western blot. The expression of phosphorylated PDGF receptor β (p-PDGFRβ), PDGFRβ, phosphorylated extracellular signal-regulated kinase (p-ERK), and ERK was detected using Western blot and immunofluorescent staining was used to explore the mechanisms. Both PDGF-BB and TGF-β1 significantly up-regulated the expression of collagen I, hydroxyproline, and α-SMA. Endostatin significantly attenuated both the PDGF-BB- and TGF-β1-induced over-expression of collagen I, hydroxyproline, and α-SMA. PDGF-BB and TGF-β1 both promoted the expression of PDGFR, ERK, and p-ERK. Endostatin inhibited the expression of PDGFR and p-ERK but did not affect the expression of total ERK. Endostatin inhibited hypertrophic scar by modulating the PDGFRβ/ERK pathway. Endostatin could be a promising multi-target drug in future fibrosis therapy.  相似文献   

10.
INTRODUCTION Bronchioloalveolar carcinoma (BAC) is a par-ticular subtype of pulmonary adenocarcinoma de-rived from clara cell and type II pneumocyte. BAC cells grow along and within alveolar spaces while the alveolar framework of the lung is preserved. The incidence of BAC appears to be rising recently. The etiology and pathogenesis of this unique neoplastic disease are still unclear; many studies of oncogene and tumor suppressor gene expression include BAC with all adenocarcinoma o…  相似文献   

11.
目的探讨格列美脲对老年2型糖尿病(T2DM)治疗的有效性及安全性。方法给予78例老年T2DM患者格列美脲1~4 mg降糖治疗,疗程3个月,比较治疗前后患者血糖指标变化情况。结果空腹血糖、餐后2 h血糖、糖化血红蛋白水平均较治疗前显著变化(P〈0.05),血压、血脂水平较治疗前无显著变化(P〉0.05),未对患者肝肾功能产生不良影响。结论格列美脲治疗老年T2DM临床疗效良好,安全性高,不良反应小,患者服药依从性高,可作为老年T2DM的首选降糖药。  相似文献   

12.
This study was aimed to investigate the relationship between breakfast and serum glucose, insulin and glucagon concentrations in order to establish a model breakfast appropriate for Chinese. Twenty-four volunteers were randomly assigned to four study groups: high carbohydrate breakfast, high fat and protein breakfast, the typical breakfast and fasting. Each subject had serum and urine samples collected while fasting and at 1,2 and 3.5 hours following the meal. The concentration of serum glucose, insulin and glucagon was measured. The levels of serum glucose in group A,B and C differed significantly at 1 and 2 hour after meal compared to those at fasting (P<0.05). The serum glucose in group A increased insignificantly after meal. The serum insulin levels were in group A,B and C significant different compared with control group(P<0.05).Those peaked at 1 hour after meal ,with group C rising the furthest. Compared with the fasting group, the serum glucagons rose and maintained the increase after breakfast in group A,B and C (P<0.05).The data suggested that various diets with different calorigenic amounts increased hormone concentration to various extents. We found that a breakfast rich in carbohydrates could maintain proper blood glucose level.  相似文献   

13.
目的:观察镍铬合金烤瓷冠修复后头发和血液中镍铬元素含量的变化,探讨镍铬合金长期存在于口腔中的安全性。方法:选取60名经体检合格的健康人作为正常对照组;60名上、下颌前牙有任意三颗行镍铬合金烤瓷冠修复的患者作为实验组。实验组修复后半年及一年和对照组均采用火焰原子吸收光谱法测定头发镍铬元素含量,采用石墨炉原子吸收光谱法测得其血清中镍铬元素含量。结果:头发镍含量:实验半年组与对照组比较无显著性差异(P>0.05);实验一年组与对照组相比较有显著性差异(P<0.05);实验一年组与半年组比较无显著性差异(P>0.05)。头发铬含量:各组之间比较均无显著性差异(P>0.05)。血清镍含量:实验半年组与对照组比较无显著性差异(P>0.05);实验一年组与对照组相比较有显著性差异(P<0.05);实验一年组与半年组比较无显著性差异(P>0.05)。血清铬含量:各组之间比较均无显著性差异(P>0.05)。结论:镍铬合金烤瓷冠修复后会在口腔环境中释放一定的镍、铬,且释放的量与时间有关,但量很微小,头发和血液中镍铬元素含量呈正相关。  相似文献   

14.
Objective: We investigated the effects of intermittent negative pressure on osteogenesis in human bone marrow-derived stroma cells (BMSCs) in vitro. Methods: BMSCs were isolated from adult marrow donated by a hip osteoarthritis patient with prosthetic replacement and cultured in vitro. The third passage cells were divided into negative pressure treatment group and control group. The treatment group was induced by negative pressure intermittently (pressure: 50 kPa, 30 rain/times, and twice daily). The control was cultured in conventional condition. The osteogenesis of BMSCs was examined by phase-contrast mi-croscopy, the determination of alkaline phosphatase (ALP) activities, and the immunohistochemistry of collagen type I. The mRNA expressions of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) in BMSCs were analyzed by real-time poly-merase chain reaction (PCR). Results: BMSCs showed a typical appearance of osteoblast after 2 weeks of induction by intermit-tent negative pressure, the activity of ALP increased significantly, and the expression of collagen type 1 was positive. In the treatment group, the mRNA expression of OPG increased significantly (P<0.05) and the mRNA expression of OPGL decreased significantly (P<0.05) after 2 weeks, compared with the control. Conclusion: Intermittent negative pressure could promote os-teogenesis in human BMSCs in vitro.  相似文献   

15.
Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   

16.
血清镍铬元素含量检测用于镍铬合金烤瓷冠修复的研究   总被引:12,自引:0,他引:12  
目的:研究镍铬合金烤瓷冠修复后血清中镍铬元素含量的变化,探讨镍铬合金长期存在于口腔中的安全性。方法:选取60名经体检合格且无任何病史的健康人作为正常对照组,采用石墨炉原子吸收光谱法测得其血清中镍铬元素含量;再从我院修复科选取60名上、下颌前牙有任意三颗行镍铬合金烤瓷冠修复后半年和一年的血清中镍铬元素含量作为实验组,并对实验组和对照组的镍铬元素含量进行分析。结果:血清镍含量:实验半年组与对照组比较无显著性差异(P〉0.05);实验一年组与对照组相比较有显著性差异(P〈0.05);实验一年组与半年组比较无显著性差异(P〉0.05)。血清铬含量:各组之间比较均无显著性差异(P〉0.05)。结论:镍铬合金烤瓷冠修复后会在口腔环境中释放一定的镍和铬,但量很微小,远低于对人体产生毒副作用的水平。  相似文献   

17.
Objective: To evaluate the efficacy and the indication of basic fibroblast growth factor (bFGF) in the treatment of exposure of orbital implants. Design: Retrospective and observational case series. Methods: We reviewed 41 patients (41 eyes) suffering exposure of orbital implants from Jan. 2000 to June 2006. The study group patients with mild exposure received combined treatment with bFGF and antibiotic drops, and while the control group patients with mild exposure were treated with antibiotic drops only. The study group patients with moderate and severe exposure received combined treatment with bFGF and antibiotic drops, and after 2 months they were subjected to amniotic membrane transplantation, while the control group patients with moderate and severe exposure underwent amniotic membrane transplantation after using antibiotic drops. Observation of the growth of conjunctival epithelium and comparison of the healing rate of the two groups. Results: The healing rates of the mild, moderate and severe exposure study group were 100% and 92.3%. The healing rates of the mild, moderate and severe exposure control group were 55.6% and 66.7% respectively. The difference of the healing rates of the mild exposure study group and the control group was significant (P=-0.033). And the difference of the healing rates of the moderate and severe exposure study group and the control group was not significant (P=-0.167). Conclusion: bFGF may promote obviously the healing of orbital implant exposure, particularly it can be the first choice for the treatment of mild degree exposure. For the moderate and severe cases, it can be administered before surgical repair to enhance neovascularization and will tend to increase the success rate of surgical repair.  相似文献   

18.
This study was aimed to investigate the level of sEGF in CAG with different therapies of either Chinese traditional medicine or western medicine. Patients were divided into spleen-reinforcingⅠ, spleen-reinforcing Ⅱ,dampness-resolving and western medicine group by Differentiation Syndrome. Healthy volunteers acted as controls. The sEGF was investigated before and after treatment. The level of sEGF in CAG was higher than that in control group(P<0.01). In patients of spleen-reinforcingⅠgroup and spleen-reinforcing Ⅱgroup, the symptoms and pathological manifestations were improved dramatically (P<0.01) and sEGF dropped markedly after treatment(P<0.01 and P<0.05).The level of sEGF in the dampness-resolving group increased after treatment (P<0.05). But the level of sEGF in the western-medicine group dropped a little after treatment (P>0.05). The inflammation of gastric mucosa may cause the elevation of sEGF in CAG reflectively. After being effectively treated with Chinese traditional medicine, the symptoms of CAG improved simultaneously with the return of sEGF. SEGF is a sensitive index to prognosis of CAG.  相似文献   

19.
Objective: to evaluate cilazapril in vasovagal syncope treatment. Method: eighty-six cases of VVS patients found positive in TTT tilt were medicated with 2.5 mg cilazapril daily for three months and followed up by TTT. Results: seven cases quit due to cough or unexplained reason; 79 VVS patients had no more fainting spells; 75.95% of TTT results of patients changed to negative after 3 months therapy. The before and after cilazapril treatment average blood pressures (taken in lying position) were 121/73 mm Hg (1 mm Hg=0.133kPa) and 120/76 mm Hg respectively (P>0.05); and mean heart rates were 68.63±12.37/min and 70.13±13.15/min respectively with no significant changes (P>0.05). Conclusion: Cilazapril was effective in treatment of VVS; did not affect normal blood pressure and heart rate; was safe; and had little side effect.  相似文献   

20.
目的:探讨胸苷酸合成酶(TS)和雌激素受体(ER)在乳腺癌中的表达及它们的相关性.方法:采用免疫组织化学SP法检测111例乳腺癌和38例乳腺腺瘤组织中TS和ER的表达情况.结果:乳腺腺瘤的TS和ER阳性率分别为10.53%(4/38)和36.84%(14/38),差异有显著性(P<0.05);乳腺癌病人中TS和ER的阳性率分别为31.53%(35/111)和40.54%(45/111),差异无显著性(P>0.05).乳腺癌中TS和ER的表达水平与患者年龄、发生部位、组织学类型、淋巴结转移相关性不明显(P>0.05).TS和ER在乳腺腺瘤组呈正向相关(r=0.077),而在乳腺癌组呈负向相关(r=-0.016).结论:TS在乳腺癌组表达率明显高于腺瘤(P<0.0 5);ER在良、恶性乳腺肿瘤内表达率差异无显著性(P>0.05).检测TS、ER对化疗药物选择有指导意义.  相似文献   

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