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排序方式: 共有982条查询结果,搜索用时 15 毫秒
1.
Lenka A. Taylor Jann Arends Arwen K. Hodina Clemens Unger Ulrich Massing 《Lipids in health and disease》2007,6(1):17
Background
It has been observed that ras-transformed cell lines in culture have a higher phosphatidylcholine (PC) biosynthesis rate as well as higher PC-degradation rate (increased PC-turnover) than normal cells. In correspondence to these findings, the concentrations of the PC-degradation product lyso-phosphatidylcholine (LPC) in cancer patients were found to be decreased. Our objective was the systematic investigation of the relationship between LPC and inflammatory and nutritional parameters in cancer patients. Therefore, plasma LPC concentrations were assessed in 59 cancer patients and related to nutritional and inflammatory parameters. To determine LPC in blood plasma we developed and validated a HPTLC method. 相似文献2.
Brezinová J Zemanová Z Ransdorfová S Sindelárová L Sisková M Neuwirtová R Cermák J Michalová K 《Cancer Genetics and Cytogenetics》2005,160(2):188-192
Deletions of the long arm of chromosome 20 represent a common chromosomal abnormality associated with myeloid malignancies, in particular with myeloproliferative disorders (MPD), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Using G-banding cytogenetic techniques, we found clones with del(20q) in 36 patients with hematological malignancies examined in our laboratory during the years 2001–2003: in 23 patients as a sole cytogenetic aberration and in 13 patients together with other chromosomal changes. Fluorescence in situ hybridization (FISH) with a probe specific for the 20q12 region was used in all cases to confirm the presence of the clone with deletion. For patients with additional or complex chromosomal rearrangements, multicolor FISH (M-FISH) analysis was performed. Statistical evaluation of the prognostic impact of sex, age, diagnosis, and karyotype was performed. The survival time correlated with the type of chromosomal aberration; no significant differences in survival were found for sex, age, and diagnosis. 相似文献
3.
Ziad A Eliska M Hubert V Lenka M Petr D Sylva S Marika T Jaroslava V Eva R 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2004,47(4):267-272
The aim of this study is to report our 3years experience with the screening of congenital disorders of glycosylation. A common isoelectric focusing method with immunofixation was used for analysis of serum transferrin and alpha1-antitrypsin, apart from several other procedures. A group of about 1000 individuals, both healthy controls and patients, mostly with signs of a metabolic disease were examined. Here we present an overview of (1) hypoglycosylation findings, (2) distribution of protein variants, (3) misguiding rare Tf variants found in our set, and (4) association of some phenotypes with various diseases. 相似文献
4.
Germline mutations in breast cancer susceptibility genes, BRCA1 and BRCA2, are responsible for a substantial proportion of high‐risk breast and breast/ovarian cancer families. To characterize the spectrum of BRCA1 and BRCA2 mutations, we screened Czech families with breast/ovarian cancer using the non‐radioactive protein truncation test, heteroduplex analysis and direct sequencing. In a group of 100 high‐risk breast and breast/ovarian cancer families, four novel frame shift mutations were identified in BRCA1 and BRCA2 genes. In BRCA1, two novel frame shift mutations were identified as 3761‐3762delGA and 2616‐2617ins10; in BRCA2, two novel frame shift mutations were identified as 5073‐5074delCT and 6866delC. Furthermore, a novel missense substitution M18K in BRCA1 gene in a breast/ovarian cancer family was identified which lies adjacent just upstream of the most highly conserved C3HC4 RING zinc finger motif. To examine the tertiary structure of the RING zinc finger domain and possible effects of M18K substitution on its stability, we used threading techniques according to the crystal structure of RAG1 dimerization domain of the DNA‐binding protein. © 2000 Wiley‐Liss, Inc. 相似文献
5.
Dobrovolny R Dvorakova L Ledvinova J Magage S Bultas J Lubanda JC Elleder M Karetova D Pavlikova M Hrebicek M 《Journal of molecular medicine (Berlin, Germany)》2005,83(8):647-654
We have identified 21 different -galactosidase A gene (GLA) mutations in 22 unrelated Czech and Slovak families with Fabry disease. Eleven of these mutations were novel (point mutations D93N, A135V, D155H, G171R, Q280K, G360S, Q330X, splicing errors c.194ins14, c.801ins36 and deletions c.674_732del59, g.3405_6021del2617). Genotyping of family members for family-specific mutations revealed 55 heterozygotes that manifested clinical symptoms of different severity. To examine the contribution of X-inactivation skewing to disease manifestation in Fabry heterozygotes, we have adopted the Mainz severity scoring scheme and compared the score values with the X-inactivation status in 39 carriers in an age-dependent manner. The age-score trendline of Fabry females who had a predominantly inactivated X-chromosome bearing a wild-type GLA allele (10 of 38 females) was markedly steeper than in the rest of the cohort. One female carrier with an inactivated mutated allele had a low score value when compared to the other heterozygotes of the same age. These data suggest that X-inactivation is indeed a major factor determining the severity of clinical involvement in Fabry heterozygotes. There was a statistically significant difference between the severity score values of heterozygotes with random and non-random X-chromosome inactivation at the 5% level of significance. Further studies will show if the degree of the wildtype allele inactivation will be useful as a predictive marker of severity of phenotype in Fabry heterozygotes. Although the correlation between X-inactivation skewing and presentation of the disease in Fabry heterozygotes has previously been suggested in the literature, this report is among the first attempts to examine this relationship systematically. 相似文献
6.
Alena Jiroutova Rastislav Slavkovsky Martina Cermakova Lenka Majdiakova Irena Hanovcova Radka Bolehovska Milena Hajzlerova Hana Radilova Ema Ruszova Jiri Kanta 《Experimental and toxicologic pathology》2007,58(4):263-273
Hepatic stellate cells (HSC) and liver myofibroblasts (MFB) are two cell populations most likely responsible for the synthesis of most connective tissue components in fibrotic liver. They differ in their origin and location, and possibly in patterns of gene expression. Normal and carbon tetrachloride-cirrhotic livers from rats were used to isolate HSC. Liver was perfused with pronase and collagenase solutions, followed by centrifugation of the cell suspension on a density gradient. HSC were quiescent 2 days after plating on plastic but they became activated after another 5 days in culture. When the culture was passaged 5 times, its character changed profoundly as HSC were replaced by MFB. Microarray analysis was used to determine gene expression in quiescent HSC, activated HSC and MFB. The expression of 49 genes coding for connective tissue proteins, proteoglycans, metalloproteinases and their inhibitors, growth factors and cellular markers was determined. The pattern of gene expression changed during HSC activation and there were distinct differences between HSC and MFB. Little difference between normal cells and cells isolated from cirrhotic liver was found. 相似文献
7.
Martin Dosedl Eduard Jirkovský Kateina Mackov Lenka Kujovsk Kr
mov Lenka Javorsk Jana Pourov Laura Mercolini Fernando Remio Lucie Novkov Pemysl Mladnka 《Nutrients》2021,13(2)
Vitamin C (L-ascorbic acid) has been known as an antioxidant for most people. However, its physiological role is much larger and encompasses very different processes ranging from facilitation of iron absorption through involvement in hormones and carnitine synthesis for important roles in epigenetic processes. Contrarily, high doses act as a pro-oxidant than an anti-oxidant. This may also be the reason why plasma levels are meticulously regulated on the level of absorption and excretion in the kidney. Interestingly, most cells contain vitamin C in millimolar concentrations, which is much higher than its plasma concentrations, and compared to other vitamins. The role of vitamin C is well demonstrated by miscellaneous symptoms of its absence—scurvy. The only clinically well-documented indication for vitamin C is scurvy. The effects of vitamin C administration on cancer, cardiovascular diseases, and infections are rather minor or even debatable in the general population. Vitamin C is relatively safe, but caution should be given to the administration of high doses, which can cause overt side effects in some susceptible patients (e.g., oxalate renal stones). Lastly, analytical methods for its determination with advantages and pitfalls are also discussed in this review. 相似文献
8.
Lenka L Allan Koren K Mann Raymond A Matulka Heui-Young Ryu Jennifer J Schlezinger David H Sherr 《Toxicological sciences》2003,76(2):357-365
Environmental polycyclic aromatic hydrocarbons (PAH) and related halogenated hydrocarbons are immunotoxic in a variety of systems. In a model system of B lymphopoiesis, PAH exposure rapidly induces apoptosis in CD43- pre-B and CD43+ pro/pre-B cells. Apoptosis induction by 7,12-dimethylbenzo[a]anthracene (DMBA) is dependent upon AhR+ bone marrow stromal cells and likely involves DMBA metabolism within the stromal cell. However, it is not known if PAH-treated stromal cells release free metabolites or soluble factors that may directly induce B cell death or if the effector death signal is delivered by stromal cell-B cell contact. Here, we demonstrate that supernatants from DMBA-treated bone marrow stromal cells contain an activity capable of inducing apoptosis in pro/pre-B cells cocultured with stromal cells. This activity (1) is not produced when stromal cells are cotreated with DMBA and alpha-naphthoflavone (alpha-NF), an aryl hydrocarbon receptor (AhR) and cytochrome P-450 inhibitor, (2) is > or = 50 kDa, (3) is trypsin and heat sensitive, and (4) is dependent on AhR+ stromal cells, which in turn deliver the effector death signal to pro/pre-B cells. The results (1) argue against a role for a soluble, stromal cell-derived cytokine as the effector of PAH-induced pro/pre-B cell death, (2) exclude the possibility of a free metabolite acting directly on AhR- pro/pre-B cell targets, and (3) suggest the elaboration by stromal cells of a relatively stable, DMBA metabolite-protein complex capable of acting on other stromal cells at some distance. Collectively, these studies suggest that, while stromal cell products, e.g., metabolite-protein complexes, may affect the function of distant stromal cells, the effector death signal delivered by stromal cells to bone marrow B cells is mediated by cell-cell contact. 相似文献
9.
Carla Sharp Amanda Venta Lochner Marais Donald Skinner Molefi Lenka Joe Serekoane 《AIDS and behavior》2014,18(6):1174-1185
Due to the HIV/AIDS pandemic which has left 12 million children orphaned in Sub-Saharan Africa, children are at increased risk for mental health problems. Currently, no validity data exist for any screening measure of emotional-behavior disorders in pre-adolescent children in Sub-Saharan Africa. The aims of the current study were to evaluate the construct validity of the caregiver-, teacher-, and self-report versions of the one-page Strengths and Difficulties Questionnaire (SDQ) in 466 orphans in South Africa between the ages of 7 and 11 (M age = 9.23 years, SD = 1.33, 51.93 % female) and to provide, for the first time, clinical cut-offs for this population. Findings demonstrated support for the caregiver SDQ, but not the teacher and self-report versions. We provide clinical cut-offs, but caution their use before further research is conducted. There remains a critical need for further psychometric studies of the SDQ in the developing world. 相似文献
10.