Apple bagasse as a substrate for the propagation of Patagonian wine yeast biomass.

AIMS: A culture medium based on apple bagasse was designed and tested as a substrate for biomass production of conventional and unconventional native wine yeasts. METHODS AND RESULTS: The physicochemical characterization of the apple bagasse was carried out and its potential utility as a constituent of a complete culture medium for the production of yeast biomass was analysed using the experimental statistical designs. Growth parameters of conventional and nonconventional Patagonian wine yeasts were analysed with Placket-Burman designs and response surface methodology, comparing in each assay the apple bagasse substrate with the commonly used substrate for biomass development, cane molasses. Culture media composition was optimized and models were validated. CONCLUSIONS: This study demonstrates that, both from a nutritional and from an economic point of view, apple bagasse constitutes a more advantageous substrate than cane molasses for the propagation of native yeasts from Patagonia. SIGNIFICANCE AND IMPACT OF THE STUDY: We used an alternate carbon-rich material, generously available in our region, originally generated as fruit industrial waste, to transform it into a source of sustainable, economically profitable and environmentally friendly energy resource.

Pigmented villonodular synovitis.

Pigmented villonodular synovitis is a benign proliferative disorder of the synovium of uncertain cause. It may involve tendon sheaths, bursae, or joints, the latter occurring as diffuse involvement or a localized nodule. This article reviews the clinical features of the disorder and the imaging features of the disease, concentrating on the findings and utility of MR imaging.

Percutaneous venous interventions.

Percutaneous procedures by interventional radiologists are becoming an increasingly frequent part of the overall care of patients with complex venous thrombotic diseases. Inferior vena caval filters are used in the setting of failed or contraindicated anticoagulation. Catheter-directed thrombolysis is considered for patients with extensive iliofemoral deep venous thrombosis. Venous angioplasty is often indicated for patients with dialysis shunt venous stenoses, upper extremity venous stenoses and for stenoses within venous bypass grafts. Venous stenting is often employed following angioplasty to ensure long-term procedural success. Finally, suction and mechanical thrombectomy and embolectomy are relatively new procedures that are available to optimize patient management.

Mural delivery of iloprost with use of hydrogel-coated balloon catheters suppresses local platelet aggregation.

PURPOSE: To develop reproducible and quantifiable methods for mural delivery of iloprost, a potent agent against platelet aggregation, with use of hydrogel-coated angioplasty balloons, and to determine the in vivo effect of direct iloprost delivery on platelet aggregation at the angioplasty site. MATERIALS AND METHODS: Drug loading of tritiated iloprost from an immersion solution onto hydrogel-coated balloons was evaluated as a function of balloon size (3 mm x 2 cm, 6 mm x 2 cm, 8 mm x 3 cm; n = 4 each), drug concentration (0.0715 mg/mL, 0.1072 mg/mL, 0.1430 mg/mL; n = 3 each), and duration of immersion (40 seconds, 60 seconds, 120 seconds; n = 3 each). In another set of experiments, optimal drying methods were tested to minimize drug loss within a protective delivery sheath (n = 3 each). Ex vivo angioplasty was performed on excised swine arteries to estimate how much of the drug present on the balloon could be delivered to the wall (n = 3 iliac segments). Finally, in vivo angioplasty was performed in three Yorkshire pigs (n = 6 iloprost-treated and 6 control arteries) and indium-111-labeled platelet aggregation was measured at these sites, which were harvested 1 hour after the procedure. RESULTS: In the initial set of experiments, the authors found that the volume of drug loaded is determined by the wet-volume of the hydrogel coating, that the majority of volume loading occurs within the first 2 minutes, and that the volume uptake is independent of the drug concentration. The optimal drying method resulting in the least loss of iloprost within the sheath (only 4%) was prolonged drying (5 hours) under ambient conditions. Ex vivo angioplasty experiments showed that approximately 33% of the drug present on the balloon can be delivered to the wall. Finally, in vivo experiments showed that platelet aggregation is significantly suppressed at treated sites (by approximately 33% compared to control sites; P = .03) by minuscule mural doses of iloprost (roughly estimated at under 1 microg). CONCLUSION: Quantifiable and reproducible methods for loading iloprost onto hydrogel-coated angioplasty balloons were developed. The best of these methods was able to deliver enough iloprost into the wall to significantly reduce local platelet aggregation.

Cyclosporine neurotoxicity and its relationship to hypertensive encephalopathy: CT and MR findings in 16 cases.

OBJECTIVE: The neurotoxic effects of cyclosporine therapy are well known but poorly understood. Imaging studies typically show subcortical edema predominantly affecting the posterior regions of the brain. We sought to determine the causes for these findings by comparing radiographic data with various clinical parameters. MATERIALS AND METHODS: In a 3-year period, 16 patients with neurologic findings attributed to cyclosporine therapy were examined with CT, MR imaging, or both. In most cases, imaging was performed both at the onset of the neurologic syndrome and after it had resolved. The radiographic findings were evaluated with respect to lesion location and changes over time. Various clinical and laboratory data obtained throughout the patients' hospital course were also reviewed, including cyclosporine levels, blood pressure values, hematologic data, and serum levels of cholesterol, magnesium, creatinine, and albumin. RESULTS: The only major factor associated with the neurotoxic effects of cyclosporine in all patients was systemic hypertension. Microangiopathic hemolytic anemia, thrombocytopenia, and hypoalbuminemia were also common, and patients usually displayed signs of sympathetic overactivation. The onset of neurologic symptoms was unrelated to serum levels of creatinine, magnesium, cholesterol, or cyclosporine. The clinical and radiographic findings of these patients were identical to those previously reported in patients with hypertensive encephalopathy. Findings resolved in all but one patient after reduction of blood pressure, with or without reduction in cyclosporine dose. In four patients, intracranial hemorrhages occurred during the hypertensive episode, resulting in one fatality. CONCLUSION: The clinical and radiologic findings in patients showing the neurotoxic effects of cyclosporine appear to be identical to those with hypertensive encephalopathy. Other associated factors, such as cyclosporine-induced vasculopathy or hypoalbuminemia may also play a role in the condition, and intracranial hemorrhage may occur owing to associated thrombocytopenia. Symptoms generally resolve after reduction of blood pressure, and follow-up is usually unnecessary in uncomplicated cases.

Preeclampsia-eclampsia: clinical and neuroradiographic correlates and insights into the pathogenesis of hypertensive encephalopathy.

PURPOSE: To investigate the clinical parameters that are associated with the development of brain edema of hypertensive encephalopathy in patients with preeclampsia-eclampsia. MATERIALS AND METHODS: Twenty-eight patients with preeclampsia-eclampsia and neurologic symptoms underwent magnetic resonance (MR) imaging. Clinical parameters recorded at the time of MR imaging included serum electrolytes and various indices of hematologic, renal, and hepatic function. Several data were available 1 week prior to the development of neurologic symptoms in 11 patients. Univariate analysis and multivariate logistic regression analyses were performed to study possible associations between these parameters and brain edema at MR imaging. RESULTS: The 20 patients with brain edema at MR imaging had a significantly greater incidence of abnormal red blood cell morphology (14 [82%] of 17 patients vs two [25%] of eight, P: <.005) and higher levels of lactic dehydrogenase (LDH) (339 U/L +/- 65 [SD] vs 258 U/L +/- 65, P: =.007) than the eight with normal MR imaging findings; multivariate logistic regression analysis showed a strong association with red blood cell morphology only. Moreover, LDH levels were elevated before the development of neurologic abnormalities (P: <.05). Blood pressures were not significantly different between groups at any time. CONCLUSION: Brain edema at MR imaging in patients with preeclampsia-eclampsia was associated with abnormalities in endothelial damage markers and not with hypertension level.