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81.
Chromium(III) is an essential element for carbohydrate and lipid metabolism, and various chemical forms of this element are widely used as dietary supplements. Of particular interest is [Cr3O(O2CCH2CH3)6(H2O)3]+ cation (CrProp), that has been proposed as an alternative source of Cr. However, its safety has not been studied completely. In this study we investigated the effects of CrProp supplementation on pregnancy outcome and maternal and foetal mineral status in the rat. Female Wistar rats (n = 20, 14 weeks old) were mated with males and, after successful conception were fed either AIN-93G diet supplemented with CrProp (100 mg Cr/kg diet, equals to 7.2 mg Cr/kg body mass/day) or non-supplemented diet (0.27 mg Cr/kg diet, equals to 0.02 mg Cr/kg body mass/day) for 21 days. Dams were sacrificed on 21 day of gestation, and their foetuses were examined for adverse effects. Maternal and foetal organs were analysed for minerals contents (Fe, Cu, Zn, Cr) using the AAS-method. Supplemental Cr given did not affect pregnancy outcome, litter size, body and inner organ masses, maternal blood biochemical indices. No abnormalities in gross organ morphology of foetuses were detected. Supplemental CrProp increased maternal liver and kidney Cr levels by 177% and 455%, decreased liver Cu and Zn concentrations by 9% and 12%, increased foetal liver Zn by 181%, and decreased kidney Cu level by 34%. 相似文献
82.
The aim of this study was to compare environmental quality in two sites of the river in Western Ukraine, rural (R) and industrial (I) during three seasons via a set of biochemical markers in carp Cyprinus carpio L. Upon comparing the values of the I-site with those of the R-site, we found that Mn- and Cu, Zn-superoxide dismutase (SOD) activities decreased and O(.) production increased; metallothionein (MT) and glutathione levels increased in most cases, and acetylcholinesterase (AChE) activity decreased in summer. This confirms our hypothesis about continuous environmental press at the I-site. The higher activity of catalase and lipid peroxidation (TBARS), as well as the increased levels of vitellogenin-like proteins at the R-site, compare to the I-site in spring reflects the permitting effect of agricultural discharges. According to the results of PCA, the most sensitive biomarkers of pollution are MT, TBARS, and AChE in liver. 相似文献
83.
Lyashkov AE Juhaszova M Dobrzynski H Vinogradova TM Maltsev VA Juhasz O Spurgeon HA Sollott SJ Lakatta EG 《Circulation research》2007,100(12):1723-1731
Spontaneous, localized, rhythmic ryanodine receptor (RyRs) Ca(2+) releases occur beneath the cell membrane during late diastolic depolarization in cardiac sinoatrial nodal cells (SANCs). These activate the Na(+)/Ca(2+) exchanger (NCX1) to generate inward current and membrane excitation that drives normal spontaneous beating. The morphological background for the proposed functional of RyR and NCX crosstalk, however, has not been demonstrated. Here we show that the average isolated SANC whole cell labeling density of RyRs and SERCA2 is similar to atrial and ventricle myocytes, and is similar among SANCs of all sizes. Labeling of NCX1 is also similar among SANCs of all sizes and exceeds that in atrial and ventricle myocytes. Submembrane colocalization of NCX1 and cardiac RyR (cRyR) in all SANCs exceeds that in the other cell types. Further, the Cx43 negative primary pacemaker area of the intact rabbit sinoatrial node (SAN) exhibits robust positive labeling for cRyR, NCX1, and SERCA2. Functional studies in isolated SANCs show that neither the average action potential (AP) characteristics, nor those of intracellular Ca(2+) releases, nor the spontaneous cycle length vary with cell size. Chelation of intracellular [Ca(2+)], or disabling RyRs or NCX1, markedly attenuates or abolishes spontaneous SANC beating in all SANCs. Thus, there is dense labeling of SERCA2, RyRs, and NCX1 in small-sized SANCs, thought to reside within the SAN center, the site of impulse initiation. Because normal automaticity of these cells requires intact Ca(2+) cycling, interactions of SERCA, RyR2 and NCX molecules are implicated in the initiation of the SAN impulse. 相似文献
84.
Rohrer JE Bernard ME Zhang Y Rasmussen NH Woroncow H 《Journal of evaluation in clinical practice》2008,14(2):214-217
Objective To determine whether marital status and self‐assessed mental health are independent risk factors for poor self‐rated overall health among female primary care patients. Design We conducted a cross‐sectional survey of family medicine patients treated in a clinic in rural Minnesota. Complete responses were obtained from 723 women. Self‐ratings of mental health, demographics and symptoms were used to predict self‐rated overall health. Results Women who were single, divorced or otherwise not married, or widowed had lower odds of good self‐rated overall health (OR = 0.39, P = 0.004) compared with married women. Women who were 65 years of age and over (OR = 0.31, P = 0.017), women who rated themselves as depressed (OR = 0.54, P = 0.029), and women who reported more physical symptoms (OR = 0.78, P = 0.000) also were less likely to have good health, compared with younger women, women who did not feel depressed, and women with fewer physical symptoms, respectively. Education was not independently related to health in this sample. Worry was related to health in the univariate analysis but not after controlling for self‐assessed depression. Conclusions In order to improve overall health among rural women seen in primary care settings, special attention may need to be directed at women who are single, are older, report more physical symptoms, and feel depressed. Programmes should include self‐help materials, support groups and counselling services addressing social isolation, employment and financial hardship. 相似文献
85.
This study addresses the role of the Na + /H + exchanger (NHE) in the generation of procoagulant activity in blood platelets. It was found that monensin (simulating the action of NHE) and gramicidin (causing sodium influx without concomitant H + efflux) produced a dose- and time-dependent increase in platelet procoagulant activity. Alkalinization of platelet cytosol by NH 4 Cl failed to evoke a procoagulant response. Collagen-induced procoagulant response was diminished in the absence of external Na + and in the presence of EIPA (NHE inhibitor) or GF 109203X (protein kinase C inhibitor). Phorbol ester (PMA) produced a dose- and time-dependent generation of procoagulant response which was inhibited in the absence of the external Na+ and in the presence of EIPA. Platelets stimulated by collagen and PMA accumulated 22 Na + , a phenomenon inhibited in the presence of EIPA. The data indicate that development of procoagulant activity in platelets may occur as a result of Na + influx via Na + /H + exchanger. 相似文献
86.
87.
Mariola ?liwińska-Mossoń MD Ph.D. Halina Milnerowicz Jerzy Rabczyński Stanis?aw Milnerowicz 《Archivum immunologiae et therapiae experimentalis》2009,57(4):295-301
Introduction The objective of this study was to determine the expression levels of metallothionein (MT) and p53 protein, recognized neoplastic
transformation markers, in pancreatic serous cystadenomas (SCA) and adenomocarcinomas.
Materials and Methods Neoplastic pancreatic tissue was taken from 20 patients with diagnosed benign (SCA: 5 cases) or malignant tumors (adenomocarcinomas:
15 cases) and control pancreatic tissue from healthy persons who had died in car accidents. Sections were stained with hematoxylin-eosin.
Immunohistochemical localization of MT and p53 protein was carried out by LSAB2-HRP using specific antibodies against MT and
p53.
Results Metallothionein expression was observed only in the epithelial cells of the neoplastic tissue of SCAs. MT expression in the
cystadenomas was weaker than in the healthy pancreatic tissue. No tissue was found with p53 protein expression. In the adenomocarcinomas,
positive staining for MT was observed in 67% and p53 was positive in the carcinoma cells.
Conclusion The weak MT expression and lack of p53 protein expression in pancreatic SCAs confirms the lack of local invasive potential
of the neoplastic lesion. Increased expressions of MT and p53 were observed in the less differentiated tumors. Thus the expression
of MT may be a potential prognostic marker for tumors. 相似文献
88.
Genome sequence of a proteolytic (Group I) Clostridium botulinum strain Hall A and comparative analysis of the clostridial genomes 总被引:1,自引:0,他引:1
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Sebaihia M Peck MW Minton NP Thomson NR Holden MT Mitchell WJ Carter AT Bentley SD Mason DR Crossman L Paul CJ Ivens A Wells-Bennik MH Davis IJ Cerdeño-Tárraga AM Churcher C Quail MA Chillingworth T Feltwell T Fraser A Goodhead I Hance Z Jagels K Larke N Maddison M Moule S Mungall K Norbertczak H Rabbinowitsch E Sanders M Simmonds M White B Whithead S Parkhill J 《Genome research》2007,17(7):1082-1092
Clostridium botulinum is a heterogeneous Gram-positive species that comprises four genetically and physiologically distinct groups of bacteria that share the ability to produce botulinum neurotoxin, the most poisonous toxin known to man, and the causative agent of botulism, a severe disease of humans and animals. We report here the complete genome sequence of a representative of Group I (proteolytic) C. botulinum (strain Hall A, ATCC 3502). The genome consists of a chromosome (3,886,916 bp) and a plasmid (16,344 bp), which carry 3650 and 19 predicted genes, respectively. Consistent with the proteolytic phenotype of this strain, the genome harbors a large number of genes encoding secreted proteases and enzymes involved in uptake and metabolism of amino acids. The genome also reveals a hitherto unknown ability of C. botulinum to degrade chitin. There is a significant lack of recently acquired DNA, indicating a stable genomic content, in strong contrast to the fluid genome of Clostridium difficile, which can form longer-term relationships with its host. Overall, the genome indicates that C. botulinum is adapted to a saprophytic lifestyle both in soil and aquatic environments. This pathogen relies on its toxin to rapidly kill a wide range of prey species, and to gain access to nutrient sources, it releases a large number of extracellular enzymes to soften and destroy rotting or decayed tissues. 相似文献
89.
Domanowska E Jozwicki W Domaniewski J Golda R Skok Z Wiśniewska H Sujkowska R Wolski Z Jozwicka G 《Human pathology》2007,38(5):741-746
Few published studies have addressed the correlation between multidirectional differentiation in muscle-invasive bladder cancer and its ability to metastasize. We demonstrated that histologic differentiation within a single tumor affects lymph node metastasis. We examined cystectomy specimens from 93 bladder tumors and 1085 lymph nodes. In this study, urothelial cell carcinomas (UCCs) with divergent differentiation, excluding pure divergent patterns such as squamous cell carcinoma and adenocarcinoma that tend toward a distinct biologic behavior, were subjected to histopathologic estimation. The positive lymph node ratio increased with the nonconventional differentiation number (NDN) within a tumor from 8.7% for an NDN of 0 (pure conventional UCCs) to 35.5% for an NDN of 2 or higher (mixed conventional and nonconventional [NC] UCCs showing >2 NC patterns). The positive lymph node number (PLN) was more than twice as high for an NDN of 3 or higher as compared with cases with an NDN of 0. Lymph node positivity (LP) was associated with the presence of micropapillary, lymphoma-like, plasmacytoid, giant cell, or clear cell-type tumors, and increasing PLN was associated with the presence of glandular, nested, lymphoma-like, plasmacytoid, or undifferentiated types in the primary tumor. By multivariate analysis, NDN status was determined to be an independent predictor of PLN (P = .032). Tumor stage had impact on LP (P = .002); however, in cases with a PLN of 4 or higher, the NDN became the only predictor of further dissemination (P = .016). No significant tumor grade impact on LP or PLN was found. Our results indicate that NC differentiation in the primary tumor is a good predictor of lymph node dissemination. 相似文献
90.
Histological biocompatibility of new, non-absorbable glaucoma deep sclerectomy implant 总被引:2,自引:0,他引:2
Kałuzny JJ Jóźwicki W Wiśniewska H 《Journal of biomedical materials research. Part B, Applied biomaterials》2007,81(2):403-409
We performed this study to compare the intrascleral biocompatibility of three materials: non-absorbable hydrogel contact lens polymer, non-absorbable silicone rubber, and absorbable cross-linked sodium hyaluronate. Intrascleral implantation of three different materials was performed in 13 healthy, pigmented rabbits. Implants of methacrylic hydrogel, silicone rubber, and cross-linked sodium hyaluronate were implanted in 10, 8, and 8 eyes, respectively. The animals were euthanized at 7, 30, 180, and 360 days post implantation. The eyes were enucleated and immediately fixed in 10% buffered formalin. Semithin sections were cut and stained with hematoxylin-eosin. Light microscope analysis of the specimens was performed. The least severe inflammatory reaction was observed with cross-linked sodium hyaluronate implants. The number of inflammatory cells in proximity to methacrylic hydrogel and silicone implants at all periods of follow up was similar. The thickest fibrous capsule was observed with silicone implants (average, 28.38 +/- 11.17 microm). This area was thinner with methacrylic hydrogel implants (average, 14.90 +/- 5.57 microm) and was thinnest around sodium hyaluronate implants (average, 7.21 +/- 2.33 microm). For each type of implant, the wall on the conjunctival side of the fibrous capsule was significantly thicker than the wall on the choiroidal side. The space between the implant, scleral flap, and bed was filled soon after surgery with connective tissue rich in vessels. In our study, cross-linked sodium hyaluronate had the highest intrascleral biocompatibility. Although the inflammatory responses of the sclera to methacrylic hydrogel and silicone rubber were similar in nature, a thicker fibrous capsule was generated around silicone implants. 相似文献