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151.
Objective: To examine whether different grades of placenta inflammation are associated with risk for spontaneous preterm birth, taking into consideration maternal and delivery factors. Placentas from spontaneous preterm births were compared with a control group from full-term deliveries.

Methods: Placentas from 98 full-term, 71 late preterm (gestational week 34–37), and 65 early preterm (gestational week 22–33) singleton deliveries were analysed from the Karolinska University Hospital in Stockholm. The placentas were examined for histologic chorioamnionitis (HCA) grade 1 (low) and 2 (high). Mother, child, and delivery parameters were collected from maternity centre and delivery forms.

Results: There was a relatively low incidence of HCA in the preterm groups (26.7% and 38.5% in the late and early preterm groups, respectively). HCA 2 was most common in the early preterm group and HCA 1 was most common in the full-term group. The odds of early preterm birth was lower for placentas with HCA 1 compared to HCA 2 (OR?=?0.17) and higher for placentas with HCA 2 compared to no HCA (OR?=?2.17).

Conclusions: Despite a relatively low incidence of HCA in the preterm groups, HCA 2 seems to be associated with early preterm birth whereas HCA 1 seems to be part of the full-term delivery.  相似文献   
152.
Pharmacologic interventions designed to control hyperparathyroidism (HPT) in uremic patients have limitations and potentially serious adverse clinical consequences. Hence, one still has to resort to surgical parathyroidectomy (PTX) in a considerable number of dialysis patients. The aim of the present study was to illustrate our experience with 26 renal dialysis patients who underwent surgical PTX. The main indications for PTX included iPTH > 1000 pg/mL associated with severe osteitis fibrosa, debilitating pruritus, marked soft tissue calcification, or hypercalcemia with hyperphosphatemia, which sometimes complicated vitamin D therapy. All patients were resistant to more conservative measures, including control of serum phosphate, attention to oral intake and dialysate calcium levels, and oral/intravenous administration of active vitamin-D-pulse therapy. Ultrasound and technetium 99-sestamibi scan were used to image the thyroid and the parathyroid glands. Total PTX with autotransplantation was performed in 23 patients; subtotal PTX was performed in 3 patients. Histology of frozen sections taken intraoperatively showed nodular changes in 14 and diffuse hyperplasia in 12 cases. During the 2-year follow-up period significant reductions in parathyroid hormone, alkaline phospatase blood levels, skeletal changes, and soft tissue calcifications were observed. Pruritis improved in half the cases. Some improvement in hemoglobin and hematocrit was also noticed. The complication rate after PTX was low. Transient postoperative hypocalcemia requiring intensification of calcium and vitamin D therapy was seen in cases with high preoperative alkaline phosphatase levels. Recurrence was observed in two cases. Hypoparathyroidism was not recorded. We conclude that surgical reduction of parathyroid mass is a safe and effective treatment for symptomatic disease not suppressible by pharmacologic means.  相似文献   
153.
OBJECTIVE: To explore the modulation of 5-lipoxygenase-activating protein (FLAP) and 5-lipoxygenase (5-LOX) expression in human osteoarthritic (OA) chondrocytes, their relative implications in leukotriene B(4) (LTB(4)) production, the effect of different factors on this system, and the influence of increased LTB(4) production on the synthesis of catabolic factors of cartilage. METHODS: FLAP and 5-LOX expression and LTB(4) production were monitored following treatment with transforming growth factor beta1 (TGFbeta1; 5 ng/ml) and 1,25-dihydroxyvitamin D(3) (1,25[OH](2)D(3); 50 nM) alone or in combination with selective or nonselective cyclooxygenase (COX) inhibitors, naproxen (90 mug/ml), NS-398 (10 muM), or FR122047 (5 muM), or a dual inhibitor of COX/5-LOX activity, licofelone (2.6 muM). LTB(4), prostaglandin E(2) (PGE(2)), and matrix metalloprotease 1 (MMP-1) production were measured by specific enzyme-linked immunosorbent assays, nitric oxide by the Griess reaction, and FLAP and 5-LOX expression by quantitative polymerase chain reaction. RESULTS: Human OA chondrocytes expressed both FLAP and 5-LOX. TGFbeta1 and/or 1,25(OH)(2)D(3) induced a rapid and marked enhancement ( approximately 4-13-fold) in FLAP messenger RNA (mRNA) levels, which was associated with a subsequent and late increase in LTB(4) production and PGE(2) synthesis. Treatment with COX inhibitors in the absence or presence of TGFbeta1 and 1,25(OH)(2)D(3) induced a rapid increase in LTB(4) production; this response was mediated by the sustained and significant (P < 0.01) up-regulation ( approximately 1.5-fold) of 5-LOX mRNA levels. Conversely, treatment with licofelone showed no effect on 5-LOX but significantly reduced FLAP expression levels. Coincubation of licofelone with TGFbeta1 plus 1,25(OH)(2)D(3) did not affect FLAP or 5-LOX levels. In the presence of TGFbeta1 plus 1,25(OH)(2)D(3), naproxen, but not licofelone, induced MMP-1 production and both drugs decreased nitric oxide levels. CONCLUSION: Both the eicosanoids PGE(2) and LTB(4) are important cofactors in regulating FLAP/5-LOX expression; the inhibition of PGE(2) up-regulates 5-LOX while down-regulating FLAP gene expression, and LTB(4) appears to be an up-regulating factor on the 5-LOX gene. Importantly, nonsteroidal antiinflammatory drugs up-regulate the synthesis of LTB(4), supporting the shunt hypothesis from COX to 5-LOX. We also demonstrated that LTB(4) likely contributes to the up-regulation of important catabolic factors involved in the pathophysiology of OA, such as MMP.  相似文献   
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Cytochrome P4503A4 (CYP3A4) is the principal drug-metabolizing enzyme in human liver. Drug-drug interactions (DDIs) caused by induction of CYP3A4 can result in decreased exposure to coadministered drugs, with potential loss of efficacy. Immortalized hepatocytes (Fa2N-4 cells) have been proposed as a tool to identify CYP3A4 inducers. The purpose of the current studies was to characterize the effect of known inducers on CYP3A4 in Fa2N-4 cells, and to determine whether these in vitro data could reliably project the magnitude of DDIs caused by induction. Twenty-four compounds were chosen for these studies, based on previously published data using primary human hepatocytes. Eighteen compounds had been shown to be positive for induction, and six compounds had been shown to be negative for induction. In Fa2N-4 cells, all 18 positive controls produced greater than 2-fold maximal CYP3A4 induction, and all 6 negative controls produced less than 1.5-fold maximal CYP3A4 induction. Subsequent studies were conducted to determine the relationship between in vitro induction data and in vivo induction response. The approach was to relate in vitro induction data (E(max) and EC(50) values) with efficacious free plasma concentrations to calculate a relative induction score. This score was then correlated with decreases in area under the plasma concentration versus time curve values for coadministered CYP3A4 object drugs (midazolam or ethinylestradiol) from previously published clinical DDI studies. Excellent correlations (r(2) values >0.92) were obtained, suggesting that Fa2N-4 cells can be used for identification of inducers as well as prediction of the magnitude of clinical DDIs.  相似文献   
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Oxaliplatin is a platinum-based anticancer drug that has been shown to be genotoxic to the normal cells. Vitamin E is a potent antioxidant that may protect and enhance the repair of the damaged DNA. In this study, we aimed to evaluate the genotoxic effect of oxaliplatin on DNA by measuring the frequency of chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) in cultured human lymphocytes. We also attempted to explore the potential protective effect of vitamin E on chromosomal damage induced by oxaliplatin. Results showed that oxaliplatin significantly increased the frequency of CAs (p?<?0.001) and SCEs (p?<?0.001) as compared to control. This chromosomal damage, caused by oxaliplatin, was significantly decreased by pretreatment of cells with vitamin E. Moreover, the results showed that oxaliplatin caused a significant reduction in the cell kinetic parameters, the mitotic index (MI) and the proliferative index (PI). However, vitamin E did not affect this reduction in the MI and PI. Therefore, we conclude that oxaliplatin is genotoxic, and vitamin E can prevent the chromosomal damage induced by oxaliplatin but it has no effect on oxaliplatin-induced cytotoxicity.  相似文献   
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Inflammation Research - The objective of the study is to uncover the influence of human bone marrow-derived mesenchymal stem cells (BM-MSCs) on the generation of Th17 lymphocytes in co-cultures of...  相似文献   
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