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991.
992.
IntroductionAtherosclerosis is an active process and the inflammatory component appears to be particularly correlated with the development of acute coronary syndromes (ACS). C-reactive protein (CRP) is an acute phase protein that appears in the circulation in response to inflammatory cytokines. The present study investigated the association between high-sensitivity C-reactive protein (hsCRP) on admission and follow-up prognosis after an ACS.MethodsWe included 151 consecutive patients admitted to the coronary care unit with a diagnosis of ACS (47% ST-segment elevation myocardial infarction [STEMI]). The primary endpoint was the combination of cardiac death and myocardial reinfarction during the follow-up period (median 19.8 months, interquartile range 16.3–23.7 months).ResultsThe occurrence of follow-up events was significantly related to admission hsCRP level, which was an excellent predictor of cardiac death and reinfarction during follow-up (HR 1.091, 95% CI 1.014–1.174; p=0.019). Stratifying the population based on type of ACS, adjusted by variables associated with cardiac events in univariate analysis (hsCRP, diabetes, depressed ejection fraction and GRACE risk score), hsCRP proved to be an independent predictor of follow-up outcomes only in non-STEMI patients (HR 1.217, 95% CI: 1.093–1.356, p<0.001), not in STEMI patients. The best cutoff level of hsCRP to predict follow-up outcomes was 1.1 mg/dl, with sensitivity of 77.8% and specificity of 63.2%.ConclusionAlthough the GRACE risk score is routinely used for stratification of patients with ACS, assessment of hsCRP may provide additional prognostic value in the follow-up of non-STEMI patients.  相似文献   
993.
We determined the levels of the endogenous angiogenesis inhibitors soluble vascular endothelial growth factor receptor-1 (sVEGFR-1), thrombospondin (TSP)-1 and TSP-2 in the vitreous fluid from patients with proliferative diabetic retinopathy (PDR) and correlated their levels with clinical disease activity and the levels of vascular endothelial growth factor (VEGF). Vitreous samples from 30 PDR and 25 nondiabetic patients were studied by enzyme-linked immunosorbent assay. TSP-1 was not detected. VEGF and TSP-2 levels were significantly higher in PDR with active neovascularization compared with inactive PDR and nondiabetic patients (P < 0.001 for both comparisons). VEGF, sVEGFR-1 and TSP-2 levels were significantly higher in PDR with hemorrhage compared with PDR without hemorrhage and nondiabetic patients (P = 0.0063; 0.0144; <0.001, respectively). VEGF and sVEGFR-1 levels were significantly higher in PDR without traction retinal detachment (TRD) compared with PDR with TRD and nondiabetic patients (P = 0.038; 0.022, respectively). TSP-2 levels were significantly higher in PDR with TRD compared with PDR without TRD and nondiabetic patients (P < 0.001). There was a significant correlation between levels of VEGF and sVEGFR-1 (r = 0.427, P = 0.038). Our findings suggest that upregulation of sVEGFR-1 and TSP-2 may be a protective mechanism against progression of angiogenesis associated with PDR. TSP-2 might be associated with TRD.  相似文献   
994.
Establishing a secure airway in a trauma patient is one of the primary essentials of treatment. Any flaw in airway management may lead to grave morbidity and mortality. Maxillofacial trauma presents a complex problem with regard to the patient's airway. By definition, the injury compromises the patient's airway and it is, therefore, must be protected. In most cases, the patient undergoes surgery for maxillofacial trauma or for other, more severe, life-threatening injuries, and securing the airway is the first step in the introduction of general anaesthesia. In such patients, we anticipate difficult endotracheal intubation and, often, also difficult mask ventilation. In addition, the patient is usually regarded as having a "full stomach" and has not been cleared of a C-spine injury, which may complicate airway management furthermore. The time available to accomplish the task is short and the patient's condition may deteriorate rapidly. Both decision-making and performance are impaired in such circumstances. In this review, we discuss the complexity of the situation and present a treatment approach.  相似文献   
995.
996.
BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an emerging cardiovascular risk marker. To explore the biologic role of Lp-PLA2 in atherosclerosis, we examined its expression and contribution to leukocyte activation under proatherogenic conditions. METHODS AND RESULTS: Following the induction of diabetes and hypercholesterolemia in a porcine model, a rapid increase in plasma Lp-PLA2 activity was observed at 1 month. This was accompanied by upregulated Lp-PLA2 mRNA expression by peripheral blood mononuclear cells (PBMC) at 3 months, and elevated Lp-PLA2 mRNA expression in coronary arteries at 6 months. These changes were paralleled by increased inflammatory responses by circulating PBMC (ICAM-1, IL-6), in coronary tissues (ICAM-1, VCAM-1), and the subsequent accumulation of inflammatory cells. In human PBMC, proinflammatory mediators augmented the synthesis and release of functional Lp-PLA2. Furthermore, lysophosphatidylcholine (lysoPC), a product of Lp-PLA2 activity, induced an increase in several inflammatory cytokines (IL-1beta, IL-6, TNF-alpha) in a concentration-dependent manner. In contrast, Lp-PLA2 inhibition (SB677116; 1 microM) abrogated the inflammatory response elicited by oxidized LDL. CONCLUSIONS: In an experimental model of diabetes and hypercholesterolemia, leukocyte activation was associated with augmented Lp-PLA2 expression. In vitro, Lp-PLA2 activity mediated leukocyte activation and inflammatory responses, whereas Lp-PLA2 inhibition abolished inflammatory responses induced by oxidized LDL. Collectively, these observations support a proatherogenic role for Lp-PLA2.  相似文献   
997.

Background

Facial trauma or tumor surgery in the head and face area often lead to massive destruction of the facial skeleton. Cell-based bone reconstruction therapies promise to offer new therapeutic opportunities for the repair of bone damaged by disease or injury. Currently, embryonic stem cells (ESCs) are discussed to be a potential cell source for bone tissue engineering. The purpose of this study was to investigate various supplements in culture media with respect to the induction of osteogenic differentiation.

Methods

Murine ESCs were cultured in the presence of LIF (leukemia inhibitory factor), DAG (dexamethasone, ascorbic acid and β-glycerophosphate) or bone morphogenetic protein-2 (BMP-2). Microscopical analyses were performed using von Kossa staining, and expression of osteogenic marker genes was determined by real time PCR.

Results

ESCs cultured with DAG showed by far the largest deposition of calcium phosphate-containing minerals. Starting at day 9 of culture, a strong increase in collagen I mRNA expression was detected in the DAG-treated cells. In BMP-2-treated ESCs the collagen I mRNA induction was less increased. Expression of osteocalcin, a highly specific marker for osteogentic differentiation, showed a double-peaked curve in DAG-treated cells. ESCs cultured in the presence of DAG showed a strong increase in osteocalcin mRNA at day 9 followed by a second peak starting at day 17.

Conclusion

Supplementation of ESC cell cultures with DAG is effective in inducing osteogenic differentiation and appears to be more potent than stimulation with BMP-2 alone. Thus, DAG treatment can be recommended for generating ESC populations with osteogenic differentiation that are intended for use in bone tissue engineering.  相似文献   
998.
999.
Bilateral cortisol-secreting adenomas are a rare cause of Cushing's syndrome. We report a case of a 35-year-old woman who presented with ACTH-independent Cushing's syndrome and bilateral adrenal adenomas. Adrenal venous sampling confirmed both adenomas to be hyper-secreting cortisol. She underwent bilateral laparoscopic adrenalectomy; total right and partial left adrenalectomies. At 2-year follow-up, she is maintained on low-dose fludrocortisone and hydrocortisone, and without recurrence of hypercorticolism. Laparoscopic partial adrenalectomy is a feasible option for this rare condition; however, long-term follow-up is needed to determine her total independence from steroid usage.  相似文献   
1000.
Abnormalities of micturition occur in many different diseases, have a variety of causes and take several forms. This review will focus exclusively on those abnormalities in which antidiuretic therapy may be of benefit. These conditions are primarily characterized by an increase in the total amount of urine produced (polyuria) or a circadian shift in the control of urine production and/or voiding (nocturnal enuresis, nocturia).  相似文献   
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