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991.
992.
目的 调查广州北郊南昆山自然保护区并殖吸虫流行分布状况. 方法 采集调查点山溪中螺蛳2012只,溪蟹63只,收集疫源地野山猫粪便3份,2只人工感染家猫粪便2份.检查并殖吸虫尾蚴、囊蚴和虫卵.解剖人工感染虫卵阳性猫,查找并殖吸虫成虫. 结果 螺蛳体并殖吸虫尾蚴感染率为0.15‰(3/2000).螺种为放逸短沟蜷.蟹体卫氏并殖吸虫囊蚴感染率为100%(59/59).感染度:2~516个囊蚴/只蟹,2~10个囊蚴/克蟹.蟹种为平和华溪蟹.2份野山猫粪便检出并殖吸虫卵,感染率为66.66%(2/3).解削两只人工感染阳性猫检获卫氏并殖吸虫成虫11条. 结论 首次发现广州北郊南昆山自然保护区存在严重卫氏并殖吸虫流行,为超高度疫源地(I级).鉴于卫氏并殖吸虫是我国主要致病并殖吸虫,该疫源地属国家级自然保护区,也是4A旅游区及著名的避暑胜地,游人如误饮用生山泉水,具有感染卫氏并殖吸虫的潜在危害,必须引起高度重视. 相似文献
993.
目的 探讨反义微小RNA-21寡核苷酸(antisense oligonucleotide micro RNA-21,AS-miRNA-21)抑制Tb3.1人舌鳞状细胞癌增殖的效果和机制.方法 实验分3组,①空白对照组;②无义寡核苷酸转染组;③AS-miRNA-21转染组.寡核苷酸介导转染反义寡核苷酸敲低Tb3.1细胞miRNA-21表达.使用荧光实时定量聚合酶链反应(PCR)鉴定转染后Tb 3.1细胞miRNA-21表达水平;甲基噻唑基四唑(MTT)法检测转染后Tb 3.1细胞生存率;流式细胞术检测转染后Tb3.1早期凋亡;Matrigel基质生长实验检测转染后Tb 3.1细胞生长形成球形集落能力;Transwell体外迁移实验检测转染后Tb 3.1细胞迁移能力;蛋白质印迹法检测转染后Tb3.1细胞增殖核抗原(antigen KI-.67,Ki67)、B细胞淋巴瘤2(B cell lymphoma 2,Bcl-2)、人第10号染色体缺失的磷酸酶及张力蛋白同源的基因(phosphatase and tensin homolog,PTEN)、基质金属蛋白酶2、9(matrix metalloproteinase 2/9,MMP-2、MMP-9)和组织基质蛋白酶抑制因子蛋白1(tissue inhibitor of metalloproteinase 1,TIMP-1)蛋白表达.结果 荧光实时定量PCR显示转染后miRNA-21表达水平下调;转染第4天,AS-miRNA-21转染组肿瘤细胞生长速度[(53.43±11.83)%]低于其他两组[(91.32±8.02)%和100%](F=27.02,P=0.00);细胞凋亡率显著升高[(12.23±2.92)%,F=26.641,P=0.001];AS-miRNA-21转染组细胞生长不能形成球形克隆且通过Transwell小室聚碳酸酯膜的细胞数小于空白对照组(F=268.231,P=0.000);Ki67、Bcl-2、MMP-2和MMP-9蛋白表达下调,PTEN和TIMP-1蛋白表达上调.结论 敲低miRNA-21后Tb3.1人舌癌细胞增殖与侵袭能力被抑制,并为探索miRNA-21调控人舌癌发生机制提供实验依据.Abstract: Objective To investigate the effect of micro RNA-21 (miRNA-21) knocking on the Tb3.1 human tongue squamous cell carcinoma growth. Methods Anti-sense miRNA-21 oligonucleotide was delivered with oligofectamine to suppress Tb 3. 1 tongue cancer cell growth in vitro. Real-time polymerase chain reaction (PCR) was conducted to detect the miRNA-21 expression after transfection. Methyl thiazolyl tetrazolium(MTT) assay was used to determine Tb 3. 1 cell survival rate. Apoptosis were examined by flowcytometry. Matrigel matrix and transwell assay were used to determine Tb 3.1 cell colony formation and migration ability. Antigen KI-67 (Ki67), B cell lymphoma (Bcl-2), phosphatase and tensin homolog (PTEN), matrirx metalloproteinase 2(MMP-2, MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) protein expression in Tb 3. 1 cell were measured by Western blotting. Results miRNA-21 expression was decreased in miRNA-21 antisense oligonucleotide (ASODN) group. The survival rate of Tb 3. 1 cells with AS-miRNA-21 transfection was significantly suppressed (F=27.02, P = 0.00) and early phase apoptosis(F =26. 641 ,P = 0. 001) induced in Tb 3.1 cell. Ki67, Bcl-2, MMP-2 and MMP-9 protein weredown regulated while PTEN and TIMP-1 protein expression was increased. Conclusions Blocking miRNA-21 expression in Tb3.1 cell could suppress cancer cell growth in vitro and miRNA-21 can serve as a novel target candidate for human tongue cancer gene therapy. 相似文献
994.
Deng CY Kuang SJ Rao F Yang H Fang XH Shan ZX Li XH Zhou ZL Lin QX Yang M Wu SL Yu XY Lin SG 《European journal of pharmacology》2012,683(1-3):211-216
Ranolazine is mainly used to treat patients with chronic stable angina in clinical practice. However, ranolazine does not lower significantly systemic blood pressure. The direct effect of ranolazine on vascular tone remains unknown. In the present study, we investigated the vascular effects and mechanisms of action of ranolazine in isolated rat intrarenal arteries. Rings of intrarenal arteries were mounted in a small vessel myography using two stainless steel wires for the measurement of isometric tension. L-type Ca2? currents were recorded in isolated single renal arterial smooth muscle cells using patch clamp techniques in whole-cell mode. Ranolazine induced concentration-dependent relaxations in rings contracted with phenylephrine, but ranolazine failed to cause any relaxation in rings pre-contracted by U46619, 5-HT or endothelin-1. Ranolazine also induced relaxations in norepinephrine pre-contracted rings. Yohimbine failed to induce relaxation in rings pre-contracted by norepinephrine. Propranolol did not affect ranolazine-induced relaxation but the relaxant effect of ranolazine was much less than that of prazosin. Ranolazine-induced relaxations were slight but significantly attenuated by endothelial denudation. Partial inhibition was observed in endothelium-intact arteries exposed to a combination of iberiotoxin and apamin. Ranolazine at higher concentration (>30 μM) inhibited Ca2?-induced contraction in a noncompetitive manner. Ranolazine reduced L-type Ca2? currents at potentials between -30 and 50 mV in isolated renal artery myocytes. Therefore it can be said that ranolazine has significant α?-adrenergic receptor and weak calcium channel antagonistic effects in rat intrarenal arteries. 相似文献
995.
Yeh TL Chen KC Lin SH Lee IH Chen PS Yao WJ Lee SY Yang YK Lu RB Liao MH Chiu NT 《Psychopharmacology》2012,220(1):55-64
Rationale and objective
The aims of this study were to examine the differences between 32 opioid-dependent users treated with a very low dose of methadone or undergoing methadone-free abstinence and 32 controls.Methods
SPECT analysis using [99mTc] TRODAT-1 to assess striatal dopamine transporter (DAT) availability and [123I] ADAM to assess midbrain serotonin transporter (SERT) availability were performed.Results
Lower striatal DAT and midbrain SERT availabilities were noted in low-dose methadone users. History of metamphatamine use was associated with the lower striatal DAT. The striatal DAT of methadone-free abstainers was also lower than controls. The midbrain SERT availability tended to be higher in the methadone-free abstainers than the low-dose methadone users. The severity of depressive symptoms was negatively correlated with midbrain SERT availability in the opioid users.Conclusion
The availability of striatal DAT tended to be, and the availability of midbrain SERT was, lower in the opioid users. History of metamphatamine use may confound the difference in straital DAT between controls and opioid users, as midbrain SERT and depressive symptoms are also associated with opioid use and abstinence. 相似文献996.
Fan G Tao LH Yue QH Kuang TT Tang C Yang YD Luo WZ Zhou XD Zhang Y 《Planta medica》2012,78(6):641-648
Rhizoma coptidis, a broadly used medicinal plant, originates from the dried rhizomes of three species in Chinese pharmacopoeia, namely, Coptis chinensis Franch, Coptis deltoidea C. Y. Cheng et Hsiao, and Coptis teeta Wall. In this study, a novel approach using (1)H NMR spectroscopy combined with multivariate analysis was introduced to differentiate the three species and identify potential metabolic markers for better controlling the quality of rhizoma coptidis. A broad range of metabolites including alkaloids, sugars, organic acids, amino acids, and fatty acids present in rhizoma coptidis were detected by means of (1)H NMR spectroscopy. Principal component analysis (PCA) of the (1)H NMR data set showed a clear separation between all samples by PC1 and PC3, and some metabolites that could be responsible for the discrimination of the three species were identified. An analysis of variance (ANOVA) was performed to statistically verify the significance of differences in metabolite levels between species. By combining PCA and ANOVA, significantly higher contents of palmatine, coptisine, epiberberine, columbamine, and fatty acids together with lower contents of jateorrhizine were found in Coptis chinensis, whereas Coptis deltoidea and Coptis teetA showed the highest levels of sucrose and chlorogenic acid, respectively. This study indicates that metabolites of rhizoma coptidis vary with the species and the proposed method is suitable for metabolic fingerprinting analysis to check the genuine origin of rhizoma coptidis. 相似文献
997.
The purpose of this research is to investigate the effect of tanshinone IIA, an extract of the Chinese medicine Que Xie Hua Yu Tang, on uric acid nephropathy (UAN) and to elucidate the underlying mechanisms. UAN rat model was established. Fifty UAN rats were randomly allocated into 5 groups: adenine-treated group, allopurinol-treated group, and low/middle/high dose of tanshinone IIA-treated groups. Meanwhile, another 10 rats were used as normal controls. Serum uric acid (UA), blood urea nitrogen (BUN), serum creatinine (Scr), MCP-1, and IL-1β levels were measured. Histological staining was performed. Comparison between the adenine group and treatment (allopurinol and tanshinone IIA) groups showed compound treatment could attenuate the inflammation status of the kidneys and decrease serum UA levels. Among different kinds of medicine, tanshinone IIA had similar effects as allopurinol and exerted anti-inflammatory and renal protective effect in a dose-dependent manner. Furthermore, we found tanshinone IIA alone could also inhibit urate-induced MCP-1 and IL-1β overexpression both in vivo and in vitro, accompanied with inhibition of NF-κB translocation from cytosome to nucleus. Tanshinone IIA could protect rats from uric acid-induced kidney damage, probably by attenuating renal inflammatory status. 相似文献
998.
Effective non-invasive treatment of neurological diseases is often limited by the poor access of therapeutic agents into the central nervous system (CNS). The majority of drugs and biotechnological agents do not readily permeate into brain parenchyma due to the presence of two anatomical and biochemical dynamic barriers: the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB). Therefore, one of the most significant challenges facing CNS drug development is the availability of effective brain targeting technology. Recent advances in nanotechnology have provided promising solutions to this challenge. Several nanocarriers ranging from the more established systems, e.g. polymeric nanoparticles, solid lipid nanoparticles, liposomes, micelles to the newer systems, e.g. dendrimers, nanogels, nanoemulsions and nanosuspensions have been studied for the delivery of CNS therapeutics. Many of these nanomedicines can be effectively transported across various in vitro and in vivo BBB models by endocytosis and/or transcytosis, and demonstrated early preclinical success for the management of CNS conditions such as brain tumors, HIV encephalopathy, Alzheimer's disease and acute ischemic stroke. Future development of CNS nanomedicines need to focus on increasing their drug-trafficking performance and specificity for brain tissue using novel targeting moieties, improving their BBB permeability and reducing their neurotoxicity. 相似文献
999.
Li LK Kuang WJ Huang YF Xie HH Chen G Zhou QC Wang BR Wan LH 《Indian journal of pharmacology》2012,44(1):78-81
Objective:
The objective of the present study is to investigate the anti-proliferation activity of Astragalus on human hepatocellular carcinoma (HCC) cells and its mechanism.Materials and Methods:
Hepatic cancer H22 bearing mice were used to study the anti-hepatocarcinoma activity of Astragalus in vivo. The growth curve and inhibitory rate of tumor growth were measured. Cell apoptosis of each group was measured by flow cytometry (FCM). Protein expression of Bax and Bcl-2 were analyzed by immunohistochemistry (IHC). The Statistical Package for Social Sciences version 13.0 (SPSS Inc, Chicago, IL) was used for standard statistical analysis including one-way ANOVA and Student''s t-test. A value of P<0.05 was considered to be statistically significant.Results:
Astragalus significantly inhibited the growth of H22 carcinoma, with an inhibitory rate of 17.28-52.36%. FCM and immunohistochemical assay show that the cell apoptosis rate and protein expression of Bax and Bax/Bcl-2 ratio of H22 transplanted tumor in Astragalus treated group were significantly higher than the control group (P<0.05). The protein expression of Bcl-2 was significantly lower than control (P<0.05).Conclusion:
The results of the present study suggest that Astragalus has significant anti-tumor effect in vivo in inducing apoptosis of H22 tumor cells by promoting protein expression of Bax, decreasing protein expression of Bcl-2 gene, and markedly increasing the Bax/Bcl-2 ratio.KEY WORDS: Antitumor effects, apoptosis, Astragalus, H22 相似文献1000.
The aim of the present work was to evaluate the effect of deacetylated gellan gum on delivering hydrophilic drug to the posterior segment of the eye. An aesculin-containing in situ gel based on deacetylated gellan gum (AG) was prepared and characterized. In vitro corneal permeation across isolated rabbit cornea of aesculin between AG and aesculin solution (AS) was compared. The results showed that deacetylated gellan gum promotes corneal penetration of aesculin. Pharmacokinetics and ocular tissue distribution of aesculin after topical administration in rabbit eye showed that AG greatly improved aesculin accumulation in posterior segmentsrelative to AS, which was probably attributed to conjunctivital/sclera pathway. The area-under-the-curve (AUC) for AG in aqueous humor, choroid-retina, sclera and iris-ciliary body were significantly larger than those of AS. AG can be used as a potential carrier for broading the application of aesculin. 相似文献