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601.
ObjectiveTo evaluate the clinical performance and overall utility of imaging and biomarker assays in discriminating between benign and malignant ovarian masses in a Filipino population.MethodsThis is a prospective cohort study among Filipino women undergoing assessment for an ovarian mass in a tertiary center. All included patients underwent a physical examination before level III specialist ultrasonographic and Doppler evaluation, multivariate index assay (MIA2G), and surgery for an adnexal mass. Ovarian tumors were classified as high-risk for malignancy based on the International Ovarian Tumour Analysis (IOTA) – Logistic Regression 2 (LR2) score. The ovarian imaging and biomarker results were correlated with the reference standard: histological findings.ResultsAmong the 379 women with adnexal masses enrolled in this study, 291 were evaluable with ultrasound imaging, biomarker assays, and histopathological results. The risk of malignancy was higher for women classified as high-risk based on IOTA-LR2 (≥10%). The sensitivity, specificity, and diagnostic accuracy for the prediction of malignancy were 81.2%, 81%, and 0.81 (95% CI: 0.77–0.86) for IOTA-LR2; 77.5%, 66.7%, and 0.72 (95% CI: 0.67–0.77) for CA-125; and 91.3%, 41.2%, and 0.66 (95% CI: 0.62–0.71) for MIA2G. A combination of IOTA-LR2 and MIA2G significantly influenced the diagnostic performance and the result. When MIA2G was combined with IOTA-LR2 in parallel, the sensitivity (94.2%) and NPV (87.7%) increased, but the specificity (37.3%) decreased. When combined with IOTA-LR2 in series, there were fewer false positives, which resulted in improved specificity (85%).ConclusionThis study determined the utility of ovarian imaging and a second-generation multivariate index assay in predicting the risk of ovarian malignancy. IOTA-LR2 and MIA2G were useful in classifying patients with a high risk for ovarian malignancy.  相似文献   
602.
C1q-tumor necrosis factor-related protein-9 (CTRP9) is an important adipocytokine that is closely associated with cardiovascular disease. This study aimed to detect CTRP9 expression in hypertensive patients and mice and to analyze its effects on hypertension-related atherogenesis. First, circulating CTRP9 levels were detected in both nonhypertensive subjects and hypertensive patients. The results showed that plasma CTRP9 levels were increased in hypertension patients compared with control subjects and gradually elevated in the Grade I, Grade II, and Grade III groups. While nondipper state did not affect CTRP9 expression in hypertension patients. Hypertension patients with carotid atherosclerotic plaque (CAP) exhibited higher CTRP9 levels and the high CTRP9 group exhibited significantly higher CAP morbidity, CTRP9 levels were positively correlated with the occurrence of CAP. Then, effects of CTRP9 on angiotensin II (Ang II)-induced endothelial dysfunction were analyzed in vitro, and the results exhibited that treatment with Ang II significantly increased CTRP9 mRNA expression in endothelial cells (ECs), and downregulation of CTRP9 expression aggravated Ang II-induced endothelial dysfunction in ECs. Mice were infused with Ang II, and CTRP9 was also increased in Ang II-infused mice and mainly secreted by ECs. In Ang II-infused ApoE−/− mice, treatment with recombinant CTRP9 significantly reduced atherosclerotic area and alleviated endothelial dysfunction. In conclusion, our results may found that CTRP9 delayed the progression of hypertension-related arteriosclerosis by alleviating endothelial dysfunction.  相似文献   
603.
Summary This study of angiotensin II (ANG II) membrane interactions uses a combination of31P NMR spectroscopy and differential scanning calorimetry (DSC), two valuable and complementary techniques which can provide useful information about the thermotropic and dynamic properties of peptide hormones in membranes. The major conclusion from the calorimetric experiments is that ANG II affects the phase properties of hydrated dipalmitoyl-phosphatidylcholine (DPPC) bilayers by mainly broadening the pretransition area. Preliminary31P NMR data seem to confirm the DSC results by showing that ANG II produces a lowering of the pretransition temperature but affects only minimally the main phase transition. In combination, the results from the two methods may indicate that the hormone produces its effects on the phospholipid head groups while its effects on the bilayer alkyl chains are not significant. Such results can be interpreted to mean that ANG II closely interacts with the phospholipid head groups perhaps up to the level of the interface, but does not enter deeper into the membrane bilayer.  相似文献   
604.
605.
Summary Taurine is an abundant free amino acid in the plasma and cytosol. The kidney plays a pivotal role in maintaining taurine balance. Immunohistochemical studies reveal a unique localization pattern of the amino acid along the nephron. Taurine acts as an antioxidant in a variety ofin vitro andin vivo systems. It prevents lipid peroxidation of glomerular mesangial cells and renal tubular epithelial cells exposed to high glucose or hypoxic culture conditions. Dietary taurine supplementation ameliorates experimental renal disease including models of refractory nephrotic syndrome and diabetic nephropathy. The beneficial effects of taurine are mediated by its antioxidant action. It does not attenuate ischemic or nephrotoxic acute renal failure or chronic renal failure due to sub-total ablation of kidney mass. Additional work is required to fully explain the scope and mechanism of action of taurine as a renoprotective agent in experimental kidney disease. Clinical trials are warranted to determine the usefulness of this amino acid as an adjunctive treatment of progressive glomerular disease and diabetic nephropathy.  相似文献   
606.
Glucocorticoids including betamethasone (BM) are routinely administered to women entering into early preterm labor to facilitate fetal lung development and decrease infant mortality; however, fetal steroid exposure may lead to deleterious long term consequences. In a sheep model of fetal programming, BM-exposed (BMX) offspring exhibit elevated mean arterial pressure (MAP) and decreased baroreflex sensitivity (BRS) for control of heart rate by 0.5-years of age associated with changes in the circulating and renal renin-angiotensin systems (RAS). In the brain solitary tract nucleus, angiotensin (Ang) II actions through the AT1 receptor oppose the beneficial actions of Ang-(1-7) at the Mas receptor for BRS regulation. Therefore, we examined Ang peptides, angiotensinogen (Aogen), and receptor expression in this brain region of exposed and control offspring of 0.5- and 1.8-years of age. Mas protein expression was significantly lower (>40%) in the dorsal medulla of BMX animals at both ages; however, AT1 receptor expression was not changed. BMX offspring exhibited a higher ratio of Ang II to Ang-(1-7) (2.30 ± 0.36 versus 0.99 ± 0.28; p < 0.01) and Ang II to Ang I at 0.5-years. Although total Aogen was unchanged, Ang I-intact Aogen was lower in 0.5-year BMX animals (0.78 ± 0.06 vs. 1.94 ± 0.41; p < 0.05) suggesting a greater degree of enzymatic processing of the precursor protein in exposed animals. We conclude that in utero BM exposure promotes an imbalance in the central RAS pathways of Ang II and Ang-(1-7) that may contribute to the elevated MAP and lower BRS in this model.  相似文献   
607.
A breeding colony of Macaca fascicularis was established at the New England Regional Primate Center in 1977 and continued through 1984. Characterization of the offspring of this colony at 18 and 30 months of age suggested that higher blood pressure levels are hereditary in M. fascicularis, but evidence to date cannot determine if this condition is harmful to the animals.  相似文献   
608.
The effects of calcium antagonists (amlodipine) and angiotensin II receptor antagonists (telmisartan) on lipid profile and oxidative markers were investigated in Algerian hypertensive patients. At the beginning and after 1 year of antihypertensive therapy, blood samples are collected for determination of biochemical parameters (glucose, cholesterol, triglycerides, urea, creatinine) and oxidative markers (malondialdehyde, carbonyl proteins, nitric oxide, superoxide anion, vitamin C, glutathione, catalase, superoxide dismutase). The results of this study indicate that telmisartan and amlodipine are effective antihypertensive agents in the treatment of hypertension because a significant reduction in systolic and diastolic blood pressure was observed in all hypertensive patients after 1 year of treatment. Our results show also that telmisartan and amlodipine treatments counteracted hypertension-dependent lipid abnormalities and oxidative stress. Telmisartan treatment appears to be more efficient than amlodipine treatment. In addition, telmisartan, which reversed all lipid and redox changes associated with hypertension, should be prescribed, especially in hypertensive patients with hypertriglyceridemia and with severe oxidative stress.  相似文献   
609.
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