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71.
72.
Estrogens and androgens may play an important role in vascular health in both sexes. The aim of this study was to examine the relation of endogenous sex hormone levels with early markers of atherosclerosis in a cohort of apparently healthy males. 124 males (age 46.25 ± 9.56) attending a preventive medicine program were examined for unrecognised features of the metabolic syndrome. Flow-mediated dilatation (FMD) and intima-media thickness (IMT) of the common carotid artery were evaluated. Obesity parameters were recorded; estradiol, testosterone, SHBG, free testosterone, insulin, as well as glucose and lipid levels were measured. FMD was positively correlated with estradiol (r = 0.201, P = 0.041) and negatively with total cholesterol (r = -0.205, P = 0.022), low density lipoproteins (r = -0.232, P = 0.009), and triglyceride levels (r = -0.179, P = 0.046). In multivariate analysis, the association of FMD with estrogen was independent of BMI and lipid levels. No significant association between FMD and testosterone levels was found. Subjects with an increased mean IMT (> 0.73 mm, i.e., > 3rd tertile) had lower levels of free (P = 0.021) and bioavailable (P = 0.016) testosterone. In multivariate logistic regression analysis, this association was no longer significant when age or cholesterol levels were considered. Endogenous estrogen levels are associated with FMD, independently of age and lipid levels, showing a protective effect in middle-age male subjects. Circulating androgens are associated, although not independently, with structural changes such as the IMT of carotid artery; this effect is possibly influenced by lipid levels and age.  相似文献   
73.
Thrombosis plays a key role in the pathophysiology of acute coronary syndromes (ACS). The management of patients with ACS includes interventional procedures and use of antithrombotic agents acutely, and dual antiplatelet therapy (aspirin and a P2Y12 receptor antagonist) for secondary prevention. However, patients with recent ACS remain at a substantial residual risk for recurrent ischemic events or death. The idea of follow-up treatment with an oral anticoagulant on top of standard therapy seems promising. Warfarin was the first oral anticoagulant thoroughly investigated in this direction, but the widespread long-term use of warfarin in ACS has been limited by challenges associated with pharmacodynamic/pharmacokinetic deficiencies of the drug and the risk of bleeding. Novel oral anticoagulants, such as direct thrombin inhibitors (DTIs) and FXa inhibitors overcome the downsides of VKAs. Ximelagatran was the first DTI, investigated and proven to be effective in prevention of recurrent ischemic events in ACS patients, but the drug association with hepatotoxicity prompted its withdrawal. Dabigatran etexilate, apixaban, darexaban (YM150) and TAK-442 were studied in phase II dose-escalation trials in order to determine the balance between clinical effectiveness and bleeding risk in daily use with dual antiplatelet therapy, with both positive and negative results. Rivaroxaban is the only agent that completed a phase III trial, showing reduction in recurrent ischemic events rate and death from cardiovascular causes as well as all-cause death. This review summarizes the data from completed and ongoing clinical trials of the new oral anticoagulants in patients with ACS.  相似文献   
74.
Introduction  Selective and non-selective cyclo-oxygenase (COX) inhibitors impair bone healing by inhibiting prostaglandin synthesis. The purpose of this study was to evaluate the long-term effect of parecoxib, a selective COX-2 inhibitor, on bone healing in rats, when it is applied in a pattern similar to clinical treatment patterns, that is, in a high dose and for a short period after bone fracture. Method  Closed non-displaced mid-diaphyseal fractures in the middle of the left femoral shaft were generated in each animal. In the study group, parecoxib sodium (1.06 mg/kg) was administered intra-peritoneally every day for 7 days. In the control group, normal saline was administered intra-peritoneally every day for 7 days. In both groups fracture healing (bone union and callus formation) was evaluated with X-rays 28 and 42 days after surgery. Results  Bone healing was lower in the study group (60 vs. 80% in the control group 28 days after fracture and 80 vs. 90% 42 days after fracture) but this difference was not statistically significant (P > 0.05). Conclusion  Parecoxib does not have a significant long-term effect on bone healing in rats, when it is administered in a high dose and for a short period after bone fracture. Declaration  The experiments comply with the current laws of the EU, and the protocol was approved by the Local Ethics Committee on Animal Research.  相似文献   
75.

Background

Small for Gestational Age (SGA) neonates often appear with haemostatic alterations, principally due to hepatic dysfunction that results from chronic intrauterine hypoxia. Polycythaemia and thrombocytopenia are common findings in this neonatal population.

Study design

We performed a comparison of coagulation, natural inhibitors and fibrinolysis between SGA and Appropriate for Gestational Age (AGA) infants born full term [gestational age (G.A.) > 37 weeks]. Study population consisted of 188 healthy newborns, 90 of whom were SGA (62 females and 28 males), while the rest were the control group (44 females and 54 males). Blood samples were obtained within 30 minutes following birth and before the administration of vitamin K. Investigation included: PT, INR, APTT, fibrinogen, coagulation factors II, V, VII, VIII, IX, X, XI, XII, vWillebrand factor, protein C and free protein S, antithrombin (AT), APCR, tPA and PAI-1. The independent t-test was used to compare the differences between the values of haemostatic parameters.

Results

Statistical analysis revealed a significant prolongation in PT, INR, elevated levels of tPA (< 0.015, 0.01 and 0.002 respectively) and a decrease in the values of XII and free protein S (< 0.045 and 0.007 respectively) in SGA full term neonates. The two groups had similar demographic characteristics (except birth weight), without significant differences in the values of other haemostatic parameters.

Conclusions

Despite of statistically significant differences in PT, INR, values of tPA, XII and free protein S, levels of haemostatic factors range within laboratory references for healthy full term newborns. These findings were not accompanied with clinical manifestations of altered haemostasis.  相似文献   
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77.
OBJECTIVE: The aim of the present study was to identify certain clinical parameters and personality characteristics associated with various forms of psychopathology in systemic sclerosis (SSc) patients. METHODS: Fifty-six SSc patients participated in the study, and 74 healthy participants served as controls. A wide range of clinical information was collected, and the following self-report instruments were used: General Health Questionnaire, Symptom Distress Checklist-90-R, Defense Style Questionnaire, Sense of Coherence (SOC) Scale, and Hostility and Direction of Hostility Questionnaire. RESULTS: The odds of being assessed with a psychiatric diagnosis upon interview were 4.5 times greater among SSc patients compared with controls. Disease duration and lower rates of SOC were found to be associated with elevated symptoms of general psychological distress. Elevated symptoms of depression were strongly associated with esophageal involvement, hostility, and defense style used. Elevated symptoms of anxiety were mainly associated with arthritis-related painful conditions and SOC, while psychotic-like symptoms were only associated with age and a specific personality structure. CONCLUSIONS: SSc patients experience elevated symptoms of psychological distress. Several clinical parameters are associated with distress, but the role of various personality traits could not be disregarded. Early psychiatric assessment and intervention could prevent psychological distress in SSc patients.  相似文献   
78.
Idiosyncratic drug hepatotoxicity represents a major problem in drug development due to inadequacy of current preclinical screening assays, but recently established rodent models utilizing bacterial LPS co-administration to induce an inflammatory background have successfully reproduced idiosyncratic hepatotoxicity signatures for certain drugs. However, the low-throughput nature of these models renders them problematic for employment as preclinical screening assays. Here, we present an analogous, but high-throughput, in vitro approach in which drugs are administered to a variety of cell types (primary human and rat hepatocytes and the human HepG2 cell line) across a landscape of inflammatory contexts containing LPS and cytokines TNF, IFNγ, IL-1α, and IL-6. Using this assay, we observed drug-cytokine hepatotoxicity synergies for multiple idiosyncratic hepatotoxicants (ranitidine, trovafloxacin, nefazodone, nimesulide, clarithromycin, and telithromycin) but not for their corresponding non-toxic control compounds (famotidine, levofloxacin, buspirone, and aspirin). A larger compendium of drug-cytokine mix hepatotoxicity data demonstrated that hepatotoxicity synergies were largely potentiated by TNF, IL-1α, and LPS within the context of multi-cytokine mixes. Then, we screened 90 drugs for cytokine synergy in human hepatocytes and found that a significantly larger fraction of the idiosyncratic hepatotoxicants (19%) synergized with a single cytokine mix than did the non-hepatotoxic drugs (3%). Finally, we used an information theoretic approach to ascertain especially informative subsets of cytokine treatments for most highly effective construction of regression models for drug- and cytokine mix-induced hepatotoxicities across these cell systems. Our results suggest that this drug-cytokine co-treatment approach could provide a useful preclinical tool for investigating inflammation-associated idiosyncratic drug hepatotoxicity.  相似文献   
79.
80.
OBJECTIVE: To access health-related quality of life (HRQOL) in systemic sclerosis (SSc) patients using the World Health Organization Quality of Life Instrument, Short-Form (WHOQOL-BREF), and to identify the association between clinical, psychopathological, and personality parameters and SSc patients' HRQOL. METHODS: Fifty-six patients with SSc were compared with 72 patients with rheumatoid arthritis (RA), 43 with systemic lupus erythematosus (SLE), 34 with Sj?gren syndrome (SS), and 74 healthy controls. A wide range of clinical information was collected and the following self-report instruments were used: the WHOQOL-BREF, the General Health Questionnaire, the Symptom Distress Check List, the Hostility and Direction of Hostility Questionnaire, the Defense Style Questionnaire, and the Sense of Coherence scale. RESULTS: HRQOL perceived by SSc patients was significantly impaired compared with healthy controls. Initial examination of HRQOL across groups of rheumatology patients revealed similar HRQOL, but when age, pain, psychopathology, and coping strategies were taken into account, SSc patients had impaired physical health QOL in comparison with RA, SLE, and SS patients. Arthritis-related pain was closely associated with SSc patients' HRQOL. Elevated psychological distress symptoms as well as certain personality traits, such as maladaptive defenses and lower sense of coherence, were also associated with diminished HRQOL. CONCLUSIONS: Impaired psychological functioning is associated with diminished HRQOL in SSc, and consequently, treatment of depressive symptoms should be considered a priority. Moreover, assessment of HRQOL should only be used in conjunction with specific psychological distress measurements, to detect the influence of psychopathology on HRQOL.  相似文献   
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