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Yildiz Oner-Iyido?an Pernur Oner Hikmet Ko?ak Abdul Lama Figen Gürd?l Selda? Bekpinar Nurettin Unur Zeynep Ozbek-Kir 《Pharmacological research》2005,52(4):340-345
Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity. 相似文献
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Either oral, intravenous or subcutaneous 1.25 (OH)2 cholecalciferol is used in the therapy of hyperparathyroidism, which is a serious complication in patients on haemodialysis.
We studied a total of 30 patients (10 women and 20 men) and divided them into two groups depending on the different types
of dialysis membranes used. In the poly sulfone group, mean age was 43.7±0.97 years and the average dialysis period lasted
29.9±1.23 months. For the 15 cases in which we used cuprophane membrane the mean age was 40.2±1.31 years and the average dialysis
period lasted 16.2±0.86 months. The calcium level of the dialysate in both groups was 1.5 mmol/l.
According to the study protocol, the determined oral calcitriol dose was 0.07 mg/kg and it was administered intermittently.
After one month on high dose calcitriol therapy, treatment was continued with a maintenance dose of 0.03 mg/kg for a further
six months. As a phosphate binding agent, daily 3 g calcium carbonate was administered.
Before starting this treatment protocol, patients went on a 1 mg/day calcitriol therapy, although the mean PTH level was 424.63
pg/ml and the mean serum alkaline phosphatase level was 290.2 U/l. During the pretreatment period, levels of PTH, alkaline
phosphatase, ionized calcium, and total calcium remained significantly within normal limits as a result of the new therapy
protocol applied.
PTH and phosphorus clearance rates were compared in the patient groups in which different dialysis membranes had been used.
PTH and phosphorus clearances were 15.2±3 ml/min and 239.1±19.2 ml/min, respectively, in the polysulfone membrane group, and
1.1±0.3 ml/min and 112.8±9.88 ml/min, respectively, in the cuprophane membrane group (p<0.05). 相似文献
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Roles of sortase in surface expression of the major protein adhesin P1, saliva-induced aggregation and adherence,and cariogenicity of Streptococcus mutans
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Sortase is a newly discovered transpeptidase that covalently links LPXTGX-containing surface proteins to the gram-positive bacterial cell wall. In this study, the sortase gene (srtA) was isolated from Streptococcus mutans NG8 by PCR. The gene encoded a 246-amino-acid protein, including a 40-amino-acid signal peptide. The srtA gene was insertionally inactivated by a tetracycline resistance cassette. P1, a major surface protein adhesin previously shown to anchor to the peptidoglycan by the LPXTGX motif, was secreted into the culture medium by the srtA mutant. In contrast, the wild-type P1 remained cell wall associated. Complementation of the mutant with srtA restored the P1 surface expression phenotype. P1 produced by the mutant, but not that produced by the wild type and the srtA-complemented mutant, was recognized by an antibody raised against the hydrophobic domain and charged tail C terminal to the LPXTGX motif. These results suggest that the failure to anchor P1 to the cell wall is due to the lack of cleavage of P1 at the LPXTGX motif. The srtA mutant was markedly less hydrophobic than the wild type and the complemented mutant. The srtA mutant failed to aggregate in the presence of saliva or salivary agglutinin and adhered poorly to saliva- or salivary agglutinin-coated hydroxylapatite. In rats, the srtA mutant colonized the teeth poorly when sucrose was absent. When sucrose was present, the srtA mutant colonized the teeth but less effectively and induced significantly less caries (P < 0.05) than the wild-type strain. In conclusion, the sortase enzyme in S. mutans is responsible for anchoring P1 to the cell surface and plays a role in modulating the surface properties and cariogenicity of S. mutans. 相似文献
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A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2
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当归补血汤出自金元时期李东垣《内外伤辨惑论卷中·暑伤胃气论》,是一首被历代医家传承发扬的补气生血经典名方,已被收录于2018年国家中医药管理局公布《古代经典名方目录(第一批)》。通过系统梳理古籍文献及现代文献,并结合古代经典名方关键信息考证原则,对经典名方当归补血汤的历史源流、组成、剂量、炮制、制法与煎服法、功效与应用进行考证分析。共收集相关古籍文献信息604条,其中涉及中医古籍186部,其中40部(金元5部,明19部,清16部)中医古籍详细记载了组成、炮制、剂量等内容。有关当归补血汤组成,主要为当归和黄芪;根据古今剂量折算,黄芪37.3~38.1 g,当归7.5~7.6 g;黄芪宜采用蜜炙,当归为酒当归;加入水600 mL,煎至300 mL,饭前温服。该方古籍主要记载功效为血虚发热,证见肌热、燥热,烦渴引饮,目赤面红,昼夜不息,脉洪大而虚,重按无力,是补气生血名方。现代研究表明,当归补血汤常用于治疗各种贫血、糖尿病肾病、肿瘤、心脑血管疾病。上述研究结果为经典名方当归补血汤后期开发研究提供了参考依据。 相似文献
7.
Effect of water extract of Turkish propolis on tuberculosis infection in guinea-pigs. 总被引:2,自引:0,他引:2
Zeki Yildirim Süleyman Hacievliyagil Nurettin Onur Kutlu Nasuhi Engin Aydin Mine Kurkcuoglu Mustafa Iraz Riza Durmaz 《Pharmacological research》2004,49(3):287-292
Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model. 相似文献
8.
Rukiye Boran 《Pharmaceutical biology》2017,55(1):402-405
Context: There is a growing market demand for Hypericum sp., a pharmacologically active plant that has been traditionally used to treat various ailments. However, there have been limited studies on the extract or essential oil of Hypericum lydium Boiss (Hypericaceae).Objective: This study investigates for the first time the antioxidant, mutagenic and antimutagenic activity of an ethanol extract of H. lydium.Material and methods: Ethanol extract from aerial parts of H. lydium harvested from Turkey were tested for this mutagenic and antimutagenic activities (2.0–0.002?mg/plate) using Ames Salmonella/microsome test system. 4-Nitro-o-phenylenediamine (4-NPD) (3?μg/plate) for the Salmonella typhimurium TA98 and sodium azide (NaN3) (8?μg/plate) for the S. typhimurium TA100 were used as positive controls. The antioxidant activity, total antioxidant activity and phenolic constituent of the extract (2.0–0.002?mg/mL) was determined by the inhibition of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), β-carotene-linoleic acid model and by means of Folin–Ciocalteu reagent, respectively.Results: The extract showed no sign of mutagenicity at the tested concentrations (0.002–2.0?mg/mL), and showed concentration-dependent antimutagenic activity against NaN3 and 4-NPD ranging from 26.8 to 81.5%. The extract was found to be an efficient scavenger of DPPH (IC50 0.165?±?0.23?mg/mL) and to inhibit β-carotene-linoleic acid bleaching (IC50 0.39?±?0.11?mg/mL).Discussion and conclusion: These findings indicate ethanol extract of H. lydium to be a safe and effective agent that may be incorporated into new strategies for the prevention of cancer and mutagenesis. 相似文献
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