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991.
To test the hypothesis that cholesterol might suppress the beneficial effect of olive oil in atherosclerosis, we fed apoE KO mice diets containing extra virgin olive oil, either with or without cholesterol, for 10 weeks and assessed the development of atherosclerosis. Within each sex, mice were assigned randomly to one of the following four experimental groups: (1) a standard chow diet, (2) a chow diet supplemented with 0.1% cholesterol (w/w) cholesterol, (3) a chow diet enriched with 20% (w/w) extra virgin olive oil and (4) a chow diet containing 0.1% cholesterol and 20% extra virgin olive oil. On the standard chow diet, average plasma cholesterol levels were higher in males than in females. Olive oil- and cholesterol-enriched diets, separately or in combination, induced hypercholesterolemia in both sexes, and abolished the difference between the sexes in plasma cholesterol levels. The addition of cholesterol to chow or olive oil diets decreased apolipoprotein A-I significantly in females and serum paraoxonase activities in males. The latter activity was higher in females than in males. In both sexes, the size of aortic atherosclerotic lesions was similar in olive oil- and chow-fed animals and smaller than in cholesterol-supplemented groups. Size of aortic lesions were positively correlated with circulating paraoxonase activity, particularly in males, and the relationship remained after adjusting for apolipoprotein A-I and HDL cholesterol levels. Our results demonstrate that the nutritional regulation of paraoxonase is an important determinant of atherosclerotic lesions dependent on sex. They also suggest that the mere inclusion of olive oil in Western diets is insufficient and the adoption of Mediterranean diet would be more effective in retarding the development of atherosclerotic lesions.  相似文献   
992.
993.
Plasma concentration of atazanavir (ATV) may be reduced when coadministered with tenofovir (TDF) or proton pump inhibitors. Boosting ATV exposure with ritonavir (r) may make it possible to overcome these drug interactions. However, jaundice and loss of the metabolic advantages of ATV are more frequent using ATV/r than ATV alone. Herein, we assessed whether therapeutic drug monitoring (TDM) could make it possible to identify the subset of patients in whom removal of ritonavir could be attempted without risk of suboptimal plasma ATV exposure and subsequent virological failure. A total of 56 patients with undetectable plasma HIV-RNA under a stable triple regimen containing ATV 300/100 mg qd were switched to ATV 400 mg qd. Plasma ATV concentrations were measured using a reliable high-performance liquid chromatography method. Median plasma ATV C(min) fell from 880 to 283 ng/ml (p = 0.03) after removal of ritonavir. While all patients on ATV/r showed ATV plasma concentrations within therapeutic values (IC(min) above 150 ng/ml) before switching, four patients (7%) fell below this threshold after switching to ATV 400 mg qd. However, only one of this group experienced virological failure at week 24 of follow-up. TDF was part of the antiretroviral regimen in all four cases. From a total of 29 (52%) patients on ATV/r showing grade 3-4 hyperbilirubinemia, only 7 (12%) remained on it upon switching to ATV 400 mg qd (p < 0.001). Patients with complete viral suppression under ATV/r 300/100 mg qd may benefit from switching to ATV 400 mg qd guided by TDM, which may make it possible to minimize adverse events without compromising antiviral efficacy in most cases.  相似文献   
994.

Objectives

Systemic sclerosis (SSc) causes functional and structural microcirculatory dysfunction, affecting also distal extremities. Optical Near-InfraRed Spectroscopy (NIRS) of blood HbO2 saturation (stO2) is able to evaluate O2 delivery/consumption balance in the explored tissue. The NIRS-sensitive camera non-invasively detects stO2 values in superficial tissues, automatically generating 2D-imaging maps in real time. We aimed at testing whether NIRS hand imaging may evaluate peripheral microcirculatory dysfunction and its spatial heterogeneity in SSc patients compared to controls.

Methods

Forty SSc patients (aged 55.1?±?15.6 years) and twenty-one healthy controls (aged 54.3?±?14.5years, p?=?0.89) were studied by palmar hand NIRS-2D imaging. A blood pressure cuff was applied to the forearm and 3 min ischemia was induced. Images were acquired at basal conditions and every 10 seconds during 3 minutes of ischemia and 5 minutes of reperfusion. Five regions of interest were positioned on each fingertip, from the second to the fifth finger and one on the thenar eminence.

Results

A significant difference was found between controls and SSc patients in basal stO2 (84.3?±?7.5?vs. 75.4?±?10.9%, p?<?0.001), minimum stO2 (65.2?±?8.0?vs. 53.4?±?10.1%, p?<?0.001) and time to maximum stO2 during hyperemia (63?±?38?vs. 85?±?49?s, p?<?0.05). Among clinical characteristics, anti-Scl70 antibody positivity, digital ulcers history and smoke exposure affected NIRS parameters, as well as sildenafil and statins therapy. Conversely, no significant differences were found in NIRS-2D values between different nailfold-videocapillaroscopy patterns.

Conclusion

NIRS-2D imaging is a simple, automated tool to non-invasively detect regional microcirculatory impairment in SSc, which seems to add significant functional information to the morphological picture of nailfold-videocapillaroscopy.  相似文献   
995.
996.
Pulmonary perfusion scintiphotographs in patients with acute, extensive pulmonary embolism have disclosed instances in which Scintiphotographic changes thought to indicate embolic recurrence were not substantiated by clinical-angiographic observations. These spurious Scintiphotographic recurrences reflected changes in the regional distribution of pulmonary vascular resistance secondary to different rates of embolic resolution or distal migration of emboli. To document the influence of changes in vascular resistance upon perfusion scintiphotographs, studies were performed in animals subjected to various sequences of pulmonary arterial obstruction by balloon catheters. Scintiphotographic changes mimicking, but not representing, recurrence of embolism were produced. Observations in both animals and man indicate that the diagnosis of embolic recurrence based on Scintiphotographic changes alone should be made with caution, particularly in patients with multiple emboli and pulmonary hypertension.  相似文献   
997.
Summary A 9-mm granular-cell myoblastoma of the cecum found incidentally during appendectomy in a 17-year-old girl is reported. Electronmicroscopic findings favor origin of the granular cells from an undifferentiated mesenchymal (fibroblast-like) cell. Review of the small number of previously reported cases revealed three involving the cecum, one each in the ascending and transverse colon and two in the rectum. Four patients were asymptomatic and their lesions were found incidentally. Three lesions simulated malignancy clinically; these patients underwent right hemicolectomy.  相似文献   
998.
999.
BACKGROUND: Although chronic alcohol intake and chronic hepatitis C may progress to cirrhosis and hepatocellular carcinoma (HCC), few data are available about survival and probability of developing HCC in decompensated cirrhosis of both aetiologies. METHODS: This study identified factors related with probability of developing HCC and survival in a cohort of 377 consecutive patients with decompensated HCV-related cirrhosis (200 cases) or alcoholic cirrhosis (177 cases) without known HCC, hospitalized for their first hepatic decompensation, as well as to evaluate differences between both aetiologies. Patients were followed for a mean period of 39 +/- 2 months. RESULTS: During follow-up, 42 patients (11.1%) developed HCC (16.5% vs 5.1%) in groups HCV and alcohol, respectively; p = 0.0008), and 131 patients (34.7%) died (42% vs 26.6% in groups HCV and alcohol, respectively; p = 0.002). Age and HCV-cirrhosis were independently related to HCC development, while baseline age and Child-Turcotte-Pugh score were independently correlated with survival. CONCLUSION: Survival in decompensated HCV-related or alcoholic cirrhosis is influenced by age and baseline Child-Turcotte-Pugh score, without differences in cirrhosis aetiology. The risk of developing HCC is greater in HCV-related cirrhosis than in alcoholic cirrhosis.  相似文献   
1000.
AIMS: Treatment delay is a powerful predictor of survival in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). We investigated effectiveness of pre-hospital diagnosis of STEMI with direct referral to PCI, alongside more conventional referral strategies. METHODS AND RESULTS: From January 2003 to December 2004, 658 STEMI patients were referred for primary PCI at our intervention laboratory. Three predefined referral routes were compared: (1) for patients within 90 min drive of the PCI centre, pre-hospital diagnosis and direct transportation (n=166), (2) diagnosis at the interventional hospital emergency department (n=316), (3) diagnosis at local hospitals before transportation (n = 176). Pre-hospital diagnosis was associated with more than 45 min reduction in treatment delay (P = 0.001). No significant difference in in-hospital mortality was apparent in the overall study population. In the cardiogenic shock subgroup (n = 80), pre-hospital diagnosis was associated with a two-thirds reduction in in-hospital mortality (P = 0.019); mortality was only 6.2% in shock patients who underwent PCI in < 2 h. CONCLUSION: This study shows that pre-hospital diagnosis can provide a reduction in primary PCI treatment delay, and suggests the hypothesis that this referral strategy might provide survival benefits to patients with cardiogenic shock.  相似文献   
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