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1.
Inflammation but not obesity or insulin resistance is associated with increased plasma fibroblast growth factor 23 concentration in the elderly 下载免费PDF全文
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Solveig B. Larsen Aleksander Giwercman Marcello Spanò Jens P. Bonde The ASCLEPIOS Study Group 《Reproductive toxicology (Elmsford, N.Y.)》1998,12(6):391-589
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones. 相似文献
4.
M A Blankenstein J Szymczak J Daroszewski A Milewicz J H Thijssen 《Gynecological endocrinology》1992,6(1):13-17
Breast cancer tissue is able to maintain the tissue estradiol level in spite of the massive decrease in plasma estradiol associated with menopause, whereas fatty tissue from breasts with malignancies more closely reflects the changes in plasma. In the present study estrone and estradiol levels in fatty tissues from different origins were compared to evaluate the capacity of distant fatty tissues to act as estrogen reservoirs. Abdominal fat was obtained from 25 premenopausal and 20 postmenopausal women who underwent surgery for non-oncological reasons. Estrone and estradiol levels in these tissues were compared to those in breast fatty tissue from breast cancer patients. Plasma estrogen levels were not different in the two groups. In both groups, median plasma estradiol levels dropped sharply with menopause (from 363 to 40 pmol/l in breast cancer patients; from 280 to 45 pmol/l in the non-oncological patients; p less than 0.002), whereas a significant decrease in plasma estrone was observed only in the breast cancer patients (from 238 to 140 pmol/l; p less than 0.02). In premenopausal women, median estrone and estradiol levels in breast fatty tissue (1135 and 375 fmol/g, respectively) and abdominal tissue (1390 and 470 fmol/g, respectively) were not different. In postmenopausal women, however, significantly higher estrone levels (663 vs. 508 fmol/g; p less than 0.01) and estradiol levels (245 vs. 187 fmol/g; p less than 0.02) were found in abdominal fatty tissue. In view of the absolute estrogen levels in breast and abdominal fatty tissue and in plasma, we conclude, however, that it is unlikely that remote fat contributes substantially to the maintenance of estrogen levels in breast cancer tissue. 相似文献
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Treatment of End-Stage Renal Disease in Central and Eastern Europe: Overview of Current Status and Future Needs 总被引:2,自引:0,他引:2
Bolesaw Rutkowski Aleksandru Ciocalteu Ljubica Djukanovic Istvan Kiss Aleksander Kovac Momir Polenakovic Zvonimir Puretic Rafail Rozental Maria Stanaityte Irina Tareyeva Vladimir Teplan Jeff Zavitz Krivoshiev Stefan & Kveder Rado 《Artificial organs》1998,22(3):187-191
The situation of end-stage renal disease (ESRD) patients in central and eastern Europe was very poor for many years during the so called socialistic era. Economical and political liberation resulted in the significant growth of renal replacement facilities in this region. The number of hemodialysis units increased significantly (56%) during the period 1990–1996, and the number of patients treated with this modality has risen by 75%. More dramatic progress was achieved in peritoneal dialysis. The number of units performing this method of renal replacement therapy (RTT) increased by 277% and the number of patients by more than 300%. Not only quantitative but also qualitative changes were observed. More modern hemodialysis machines installed in the vast majority of units allow for the performance of bicarbonate dialysis, controlled ultrafiltration, and sodium profile modeling. Also, a wider choice of biocompatible dialyzers has become available during the last few years. The number of centers performing renal transplantation has increased significantly, but the number of renal transplants has not followed this progress. Despite all the progress, further development of all RRT methods is necessary to achieve acceptance rates comparable to those observed in developed countries. 相似文献
7.
M. Parczewski J. Kordek E. Janczewska A. Pisula W. Łojewski Ł. Socha M. Wawrzynowicz-Syczewska M. Bociąga-Jasik A. Szymczak I. Cielniak E. Siwak E. Mularska B. Aksak-Wąs A. Urbańska N. Lübke 《Clinical microbiology and infection》2019,21(4):513.e1-513.e6
Objectives
The aim of the study was to characterize the differences in the frequencies of NS3 and NS5A resistance-associated variants (RAVs) among Polish therapy-naive genotype 1 (G1) hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients including clustering patterns and association of RAV frequency with liver fibrosis.Methods
NS3/NS5A RAVs were identified by population sequencing in 387 directly acting antiviral treatment-naive G1-infected individuals (54 with genotype 1a (G1a) and 333 with genotype 1b (G1b)). Liver fibrosis was assessed based on histopathology or ultrasound elastography. Phylogenetic clusters were identified using maximum likelihood models. For statistics, chi-squared or two-sided Fisher's exact tests and multivariate logistic regression models were used, as appropriate.Results
NS3 RAVs were found in 33.33% (18/54) for G1a and 2.62% (8/297) for G1b whereas NS5A variants were present in 5.55% (3/54) G1a and 9.31% (31/333) G1b sequences. Variations in NS5A 31 and 93 codon positions were found only in G1b (4.2% (14/333) for L31I/F/M and 5.39% (17/333) for Y93H). NS5A RAVs were more frequent among patients with advanced liver fibrosis (17.17% (17/99) for F3–F4 versus 6.94% (17/245) for F0–F2; p 0.004) or liver cirrhosis (20.34% (12/59) for F4 versus 7.72% (22/285) for F0–F3; p 0.003). Liver cirrhosis (F4) was associated with higher odds ratio of the NS5A RAVs among HCV-infected patients (odds ratio 2.34, 95% CI 1.004–5.291; p 0.049). NS5A RAVs were less frequent among sequences forming clusters and pairs (5.16% (8/155) versus 11.21% (26/232); p 0.039).Conclusions
Presence of NS5A RAVs correlated with progression of liver fibrosis and represents de novo selection of variants rather than transmission of drug resistance. Hence, the presence of NS5A RAVs may be a predictor for a long-lasting HCV infection. 相似文献8.
Karyotypic evolution in Ph-positive chronic myeloid leukemia in relation to management and disease progression 总被引:1,自引:0,他引:1
Birgitta Swolin Aleksander Weinfeld Jan Westin Johan Waldenström Bengt Magnusson 《Cancer Genetics and Cytogenetics》1985,18(1):65-79
In a prospective study of 32 patients with chronic myeloid leukemia the frequency of chromosome abnormalities in addition to the Philadelphia chromosome (Ph) increased when the disease progressed. Before metamorphosis, 10 patients (31%) had developed additional abnormalities. Such abnormalities were present in three of them at the time of diagnosis; in the other seven, they were detected late in the chronic phase. New clonal abnormalities heralded or accompanied a more malignant phase of the disorder, usually a blastic leukemia. During metamorphosis, 78% of the patients had additional abnormalities, which in 68% of these cases comprised at least one of +8, +22q- or i(17q). Clones with additional abnormalities disappeared in eight cases, either spontaneously or in association with cytostatic therapy during the chronic or blastic phase. Involvement of chromosome #8, usually in the form of a trisomy, was found in 7 of 12 patients treated with busulfan, but was not found in any of the 10 hydroxyurea-treated patients, of whom 8 were splenectomized early during the chronic phase. Cells from the spleen, obtained by fine needle aspiration or splenectomy were cytogenetically examined in 18 cases during the chronic phase, but abnormalities in addition to the Ph were noted in only one patient, who was examined in the late chronic phase. The same abnormalities were present in bone marrow cells of this patient. 相似文献
9.
P-glycoprotein expression influences the result of 99mTc-MIBI scintigraphy in tertiary hyperparathyroidism 总被引:2,自引:0,他引:2
Chudzinski W Niderla J Lasiecka Z Wilczynski G Gornicka B Wasiutynski A Maczewska J Kobylecka M Krolicki L Durlik M Nowacka E Lazarczyk M Dziunycz P Milewski L Nawrot I Grzela T 《International journal of molecular medicine》2005,16(2):215-219
Precise localization of parathyroid glands using 99mTc-labeled hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) scintigraphy could be affected by various biological factors. There is increasing evidence that radiotracer retention could be controlled by members of multidrug resistance (MDR) system, especially P-glycoprotein (P-gp). Since the role of P-gp in tertiary hyperparathyroidism (T-HPTH) scintigraphic studies is poorly recognized, the aim of the study was to compare the correlation between parathyroid P-gp expression and results of their scintigraphy in T-HPTH versus primary hyperparathyroidism (P-HPTH). P-HPTH (n = 19) and T-HPTH (n = 18) patients were subjected to 99mTc-MIBI scintigraphy followed by surgical treatment. The parathyroid glands were assessed in routine hematoxylin-eosin staining and P-gp expression was analyzed using immunohistochemistry. Parathyroids collected during cadaver donor multi-organ harvesting were used as a control. It has been found that P-HPTH-derived parathyroid glands with predominating adenoma morphology expressed less P-gp, as compared to P-gp-rich T-HPTH glands, mainly displaying nodular or diffused hyperplasia phenotype. This finding reversely correlated with results of 99mTc-MIBI scintigraphy. However, we did not observe any difference in P-gp expression nor scintigraphy result between nodular or diffused hyperplasia. Altogether, these data suggest that P-gp overexpression in T-HPTH could be responsible for decreased sensitivity of 99mTc-MIBI scintigraphy in those patients. Therefore, the recently proposed reduced neck exploration or limited parathyroid resection on the basis of scintigraphy could create the risk of persisted/recurrent hyperparathyroidism. However, this problem requires further study. 相似文献
10.
Although the mechanism by which asbestos causes cancer remains unknown, iron associated with asbestos is thought to play a role in the pathogenic effects of fibers. Here, we examined the effects of asbestos on the epidermal growth factor receptor (EGFR) in human lung epithelial (A549) cells, human pleural mesothelial (MET5A) cells, and normal human small airway epithelial (SAEC) cells. Treatment of A549, MET5A, and SAEC cells with asbestos caused a significant reduction of EGFR tyrosine phosphorylation. This was both time- (15 min to 24 h) and concentration-dependent (1.5, 3, and 6 mug/cm(2)) in A549 cells. Also, treatment with 6 mug/cm(2) crocidolite for 24 h diminished the phosphorylation levels of human EGFR 2 (HER2). Exposure of A549 cells to 6 mug/cm(2) crocidolite for 3-24 h resulted in no detectable Y1045 phosphorylation and no apparent degradation of the EGFR. Inhibition of fiber endocytosis resulted in a considerable inhibition of EGFR dephosphorylation. Removal of iron from asbestos by desferrioxamine B or phytic acid inhibited asbestos-induced decreases in EGFR phosphorylation. The effects of crocidolite, amosite, and chrysotile on the EGFR phosphorylation state appeared to be directly related to the amount of iron mobilized from these fibers. These results strongly suggest that iron plays an important role in asbestos-induced inactivation of EGFR. 相似文献