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91.
Purpose: To report a series of patients with fungal orbital cellulitis who underwent exenteration surgery and describe presenting features, management and outcomes at a referral center.

Methods: Retrospective case series.

Results: From November 2011 to March 2014, four patients underwent orbital exenteration for fungal orbital cellulitis at the University of Illinois. Three patients had mucormycosis and one had aspergillosis. All patients were treated with intravenous antifungals and underwent orbital exenteration. Two patients were successfully treated with supplemental intra-orbital catheter delivery of amphotericin B. Presenting visual acuity in the affected eye ranged from 20/25 to no light perception. Some level of ophthalmoplegia was present in three patients. Significantly elevated intraocular pressure was found in two patients. All patients with mucormycosis were found to have uncontrolled diabetes mellitus. One patient had a history of myelodysplastic syndrome, chronic hepatitis C infection, polysubstance abuse and Crohn’s disease. Another patient had a history of alcoholic liver cirrhosis, Crohn’s disease treated with systemic immunosuppression and renal cell carcinoma. The patient with aspergillosis had myelodysplastic syndrome and portal hypertension, and the initial presentation resembled giant cell arteritis. Two of four patients died during their hospitalization.

Conclusions: Fungal orbital cellulitis has a high mortality rate despite aggressive antifungal treatment and orbital exenteration performed soon after the diagnosis is confirmed. Patients often have a history of immunosuppression and the onset may be insidious. There must be a high rate of suspicion for fungal orbital cellulitis given the appropriate signs and medical history in order to avoid treatment delay.  相似文献   

92.
The effects of increased brain availability of l ‐arginine (l ‐arg), a precursor for nitric oxide synthesis, on core body temperature (Tcore) and cutaneous heat loss were evaluated in running rats. One week prior to the experiments, adult male Wistar rats received the following implants: a chronic guide cannula in the lateral cerebral ventricle and a temperature sensor in the abdominal cavity. On the day of the experiments, the rats were assigned to receive a 2‐μL intracerebroventricular injection of either NaCl (0.15 mol/L) or l ‐arg solution (0.825, 1.65 or 3.30 mol/L); Tcore and tail skin temperature were measured while the rats ran at a speed of 18 m/min until they were fatigued. l ‐arginine induced a dose‐dependent reduction in the threshold Tcore required for cutaneous heat loss (38.09 ± 0.20°C for 3.30‐mol/L l ‐arg vs 38.61 ± 0.10°C for saline; P < 0.05), which attenuated the exercise‐induced hyperthermia. Although the rats treated with l ‐arg presented a lower Tcore at the end of exercise (~0.7°C lower after treatment with the highest dose), no changes in the time to fatigue were observed relative to the control trial. These results suggest that brain l ‐arg controls heat loss during exercise, most likely by modulating the sympathetic vasoconstrictor tonus to skin vessels. Furthermore, despite facilitating cutaneous heat loss mechanisms, increased brain l ‐arg availability did not enhance physical performance.  相似文献   
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OBJECTIVES: In this study, we examined whether a reconstituted high-density lipoprotein (HDL) utilizing recombinant apolipoprotein A-I(Milano) (apo A-I(M))/phospholipid complex (PC) could restore normal endothelial function in hypercholesterolemic apolipoprotein (apo) E-null mice. BACKGROUND: We have previously shown antiatherosclerotic and vasculoprotective effects of recombinant apo A-I(M). METHODS: A perfused vessel preparation was used to examine vascular responses in control wild-type, untreated, and treated apo E-null mice. Aortic tissue cholesterol content and platelet aggregation were also measured. RESULTS: Endothelium-dependent vasodilator responses to acetycholine were significantly inhibited in untreated apo E-null mice compared with control wild-type mice (p < 0.001). Treatment of the mice for five weeks with once every-other-day intravenous bolus injections of apo A-I(M)/PC restored endothelium-dependent dilation in a dose-dependent manner (p < 0.01 at 80 mg/kg dose). The improvement in endothelial function was associated with a reduction in aortic cholesterol content and reduced platelet aggregability and occurred despite severe and persistent hypercholesterolemia. Neither treatment with free protein nor phospholipid carrier alone produced any significant effects. We performed additional experiments in vitro in isolated rabbit carotid arteries to compare the effects on lysophosphatidylcholine (LPC)-induced endothelial dysfunction. Treatment with apo A-I(M)/PC prevented impairment of endothelium-dependent vasodilator responses to acetylcholine to a greater degree than either wild-type apo A-I or plasma-derived HDL. CONCLUSIONS: Our results indicate a rapid improvement in endothelial dysfunction with recombinant apo A-I(M)/PC that is associated with mobilization of tissue cholesterol. Taken together with previously established antiatherosclerotic and antithrombotic effects, these findings suggest significant vasculoprotective effects with apo A-I(M)/PC therapy.  相似文献   
96.
BACKGROUND--Serial testing with impedance plethysmography or compression ultrasonography has been demonstrated to be feasible and accurate for the detection of deep vein thrombosis (DVT) in symptomatic outpatients, and these techniques are replacing contrast venography in this patient category. Limited data, however, are available on the clinical utility of these noninvasive tests in symptomatic hospitalized patients. The objectives of our study were to determine the feasibility of ascending contrast venography and to evaluate the accuracy of these two noninvasive methods for the detection of DVT in symptomatic hospitalized patients. METHODS--A prospective, "blind" comparison of impedance plethysmography and compression ultrasonography with ascending contrast venography was performed in consecutive hospitalized patients with clinically suspected DVT of the leg. RESULTS--Of the 127 potentially eligible patients, 44 had to be excluded; 25 of these could not undergo venography (feasibility of venography, 80.3%). The sensitivity, specificity, and positive and negative predictive values of impedance plethysmography for proximal DVT were 96%, 83%, 82%, and 97%, respectively. For compression ultrasonography, these measures for proximal DVT were 97%, 86%, 87%, and 97%, respectively. The overall prevalence of DVT was 53%, of which 85% was located proximally. CONCLUSIONS--Contrast venography cannot be performed in about 20% of consecutive symptomatic patients. Both impedance plethysmography and compression ultrasonography are feasible and valid alternatives to contrast venography in the diagnostic treatment of these patients.  相似文献   
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Aims/hypothesis

The prognostic importance of the ankle–brachial index (ABI) in individuals with diabetes is controversial. We aimed to evaluate the relationship between the ABI and the occurrence of micro- and macrovascular complications in individuals with type 2 diabetes.

Methods

The ABI was measured at baseline in 668 individuals with type 2 diabetes, and the individuals were followed-up for a median of 10 years. Multivariate Cox analysis was used to examine associations between the ABI and the occurrence of microvascular (retinopathy, microalbuminuria, renal function deterioration and peripheral neuropathy) and macrovascular (total cardiovascular events, major adverse cardiovascular events [MACE] and cardiovascular mortality) complications, and all-cause mortality. The improvement in risk stratification was assessed using the C statistic and the integrated discrimination improvement (IDI) index.

Results

During follow-up, 168 individuals had a cardiovascular event (140 MACE) and 191 individuals died (92 cardiovascular deaths); 156 individuals newly developed or experienced worsening diabetic retinopathy, 194 achieved the renal composite outcome (122 with newly developed microalbuminuria and 93 with deteriorating renal function) and 95 newly developed or experienced worsening peripheral neuropathy. The ABI, either analysed as a continuous or as a categorical variable, was significantly associated with all macrovascular and mortality outcomes, except for non-cardiovascular mortality. Individuals with a baseline ABI of ≤0.90 had a 2.1-fold increased risk of all-cause mortality (95% CI 1.3, 3.5; p?=?0.004), a 2.7-fold excess risk of cardiovascular mortality (95% CI 1.4, 5.4; p?=?0.004) and a 2.5-fold increased risk of MACE (95% CI 1.5, 4.4; p?=?0.001). The ABI improved risk discrimination over classical risk factors, with relative IDIs ranging from 6.3% (for all-cause mortality) to 31% (for cardiovascular mortality). In addition, an ABI of ≤0.90 was associated with the development or worsening of peripheral neuropathy (2.1-fold increased risk [95% CI 1.1, 4.3]; p?=?0.033), but not with retinopathy or renal outcomes.

Conclusions/interpretation

A low ABI is associated with excess risk of adverse cardiovascular outcomes, mortality and peripheral neuropathy development or worsening, and improves cardiovascular risk stratification. The ABI should therefore be routinely evaluated in individuals with type 2 diabetes.
  相似文献   
99.
BACKGROUND/AIMS: We studied the influence of biochemical and virologic patterns and interferon on the outcome of anti-HBe positive chronic hepatitis B in 164 (103 treated) consecutive patients, followed-up prospectively for a mean of 6 years (21 months-12 years). METHODS: Histology, biochemical and virologic profiles were characterized by monthly monitoring during the first 12 months of follow-up. Thereafter patients underwent blood and clinical controls every 4 and 6 months, respectively. Cirrhosis at follow-up histology or end stage complications of cirrhosis served as end points for the analysis of factors influencing disease progression in patients with baseline chronic hepatitis or cirrhosis, respectively. RESULTS: Disease progression was associated with older age (P<0.001), absence of previous HBeAg history (P=0.017) and higher serum HBV-DNA levels (P=0.009) (more frequently observed in unremitting disease profile, P=0.012) at multivariate analysis. Fluctuations of IgM anti-HBc levels (associated with disease exacerbations, P=0.045) correlated with end stage complications in cirrhotics (P=0.011). Disease improved in 14.6 and 1.6% of treated and untreated patients, respectively (P=0.015): interferon slowed disease progression (P<0.001). CONCLUSIONS: The outcome of anti-HBe positive chronic hepatitis B is worsened by older age and persistent viral replication or hepatitis exacerbations in chronic hepatitis or in cirrhotic patients, respectively. Interferon reduces by 2.5-folds disease progression.  相似文献   
100.
In spite of increasing resistance, chloroquine remains the primary drug for treatment of malaria in most sub-Saharan African countries. We evaluated the effect of drug treatment policy on the case-fatality rates of children, adjusting for differing distributions of malaria and severe anemia. In 1991, 63% of children were treated with chloroquine while the remaining 37% were treated with a regimen that would eliminate and clear parasitemia. Case-fatality rates were 13% and 4.1%, respectively; the proportion of deaths attributable to chloroquine treatment was 69%. The trend in case-fatality rates for malaria decreased as an increasing proportion of children received an effective treatment regimen; adjusted malaria case-fatality rates were 5.1%, 3.6%, and 3.3% in 1992, 1993, and 1994, respectively, when 85% of children in 1992 and 97% of children in 1993-1994 received effective therapy. These 4 years of data provide strong evidence that continued use of chloroquine in areas with resistance is contributing to excess Plasmodium falciparum-related deaths.  相似文献   
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