Simultaneous analysis of parabens in cosmetic products by stir bar sorptive extraction and liquid chromatography

A sensitive and precise stir bar sorptive extraction (SBSE) combined with LC (SBSE/LC) analysis is described for simultaneous determination of methyl, ethyl, propyl, and butyl parabens in commercial cosmetic products in agreement with the European Union Cosmetics Directive 76/768/EEC. Important factors in the optimization of SB SE efficiency are discussed, such as time and temperature of extraction, pH, and ionic strength of the sample, matrix effects, and liquid desorption conditions by different modes (magnetic stirring, ultrasonic). The LOQs of the SBSE/LC method ranged from 30 to 200 ng/mg, with linear response over a dynamic range, from the LOQ to 2.5 mu g/mg, with a coefficient of determination higher than 0.993. The interday precision of the SBSE/LC method presented a coefficient of variation lower than 5%. The effectiveness of the proposed method was proven for analysis of commercial cosmetic products such as body creams, antiperspirant creams, and sunscreens.

Transfer of Cholesterol and Other Lipids From a Lipid Nanoemulsion to High-density Lipoprotein in Heart Transplant Patients

Background: Beyond the first year after a heart transplant (HT) procedure, patients often develop dyslipidemias, which may be implicated in the genesis of transplant coronary heart disease. High-density lipoprotein (HDL) has a several anti-atherogenic properties, but the status of HDL in HT patients is still controversial. Nonetheless, determination of HDL cholesterol concentration is not sufficient for evaluation of the overall HDL protective role. In this study, a fundamental functional property of HDL, the ability to simultaneously receive the major lipid classes, was tested in HT patients. Methods: Twenty HT patients and 20 healthy normolipidemic subjects paired for gender, age and body mass index were studied. Blood samples were collected after 12-hour fasting for determination of plasma lipids, glucose, paraxonase I (PON 1) activity, HDL diameter and transfer of labeled lipids from an artificial nanoemulsion to HDL. Results: Plasma triglycerides (159 +/- 63 vs 94 +/- 35 mg/dl) and glucose (104 +/- 20 vs 86 +/- 10 mg/dl) were greater in HT patients than in control subjects. HDL cholesterol was lower and HDL diameter was smaller in the HT group (HDL cholesterol: 44 +/- 11 vs 55 +/- 15 mg/dl; HDL diameter: 8.8 +/- 0.6 vs 9.0 +/- 1.2 nm). PON 1 activity did not differ (87 +/- 47 vs 75 +/- 37 nmol/min/ml). The transfer rates of free cholesterol and cholesteryl esters were diminished in HT patients (HT: 8.4 +/- 1.2% and 3.8 +/- 0.6%; controls: 9.7 +/- 1.9% and 4.7 +/- 1.2%, respectively). Conclusions: The transfer of free cholesterol and cholesteryl esters to HDL is diminished in HT patients; disturbance in the ability of HDL to receive lipids may affect the anti-atherogenic properties of the lipoprotein. J Heart Lung Transplant 2009;28:1075-80. Copyright (C) 2009 by the International Society for Heart and Lung Transplantation.

Metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein in young obese and normal-weight patients with polycystic ovary syndrome

Objective: To clarify whether the metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein (HDL) are altered in patients with polycystic ovary syndrome (PCOS). Design: Case control study. Setting: Endocrinology clinics. Patient(s): Eight normal-weight (NW) and 15 obese (013) patients with PCOS were compared with 10 NW and 10 Ob women without PCOS paired for age and body mass index. Intervention(s): Determination of triglyceride-rich lipoprotein metabolism and lipid transfer to HDL. Main Outcome Measure(s): Participants were injected triglyceride-rich emulsions labeled with (14)C-cholesteryl esters and (3)H-triglycerides and the fractional clearance rate (FCR, in min(-1)) of labels was determined. Lipid transfer from artificial nanoemulsions to HDL was performed by incubating radioactively labeled lipid nanoemulsions with plasma during 1 hour, followed by radioactive counting of HDL-containing supernatant after chemical precipitation. Result(s): Lipolysis estimated by triglyceride FCR was equal in PCOS groups (NW = 0.043 +/- 0.032, Ob = 0.033 +/- 0.009) and respective controls (NW = 0.039 +/- 0.015, Ob = 0.044 +/- 0.019). However, the remnant removal as estimated by cholesteryl ester FCR was reduced in both PCOS groups (NW = 0.005 +/- 0.006, Ob = 0.005 +/- 0.005) compared with controls (NW = 0.016 +/- 0.006, Ob = 0.011 +/- 0.072). Lipid transfer rates were not different among groups, but triglyceride transfer rates were positively correlated with homeostasis model assessment estimate of insulin resistance in PCOS. Conclusion(s): PCOS patients showed decreased removal of atherogenic remnants even when fasting glucose was <100 mg/dL. This reinforces the usefulness of the measures taken to prevent cardiovascular events in PCOS patients. (Fertil Steril (R) 2010;93:1948-56. (C)2010 by American Society for Reproductive Medicine.)

EVALUATION OF ONYX HD-500 EMBOLIC SYSTEM IN THE TREATMENT OF 84 WIDE-NECK INTRACRANIAL ANEURYSMS

OBJECTIVE: We report our results using Onyx HD-500 (Micro Therapeutics, Inc., Irvine, CA) in the endovascular treatment of wide-neck intracranial aneurysms, which have a high rate of incomplete occlusion and recanalization with platinum coils. METHODS: Sixty-nine patients with 84 aneurysms were treated. Most of the aneurysms were located in the anterior circulation (80 of 84 aneurysms), were unruptured (74 of 84 aneurysms), and were incidental. Ten presented with subarachnoid hemorrhage, and 15 were symptomatic. All aneurysms had wide necks (neck >4 mm and/or dome-to-neck ratio <1.5). Fifty aneurysms were small (<12 mm), 30 were large (12 to <25 mm) and 4 were giant. Angiographic follow-up was available for 65 of the 84 aneurysms at 6 months, for 31 of the 84 aneurysms at 18 months, and for 5 of the 84 aneurysms at 36 months. RESULTS: Complete aneurysm occlusion was seen in 65.5% of aneurysms on immediate control, in 84.6% at 6 months, and in 90.3% at 18 months. The rates of complete occlusion were 74%, 95.1%, and 95.2% for small aneurysms and 53.3%, 70%, and 80% for large aneurysms at the same follow-up periods. Progression from incomplete to complete occlusion was seen in 68.2% of all aneurysms, with a higher percentage in small aneurysms (90.9%). Aneurysm recanalization was observed in 3 patients (4.6%), with retreatment in 2 patients (3.3%). Procedural mortality was 2.9%. Overall morbidity was 7.2%. CONCLUSION: Onyx embolization of intracranial wide-neck aneurysms is safe and effective. Morbidity and mortality rates are similar to those of other current endovascular techniques. Larger samples and longer follow-up periods are necessary.

Gasless fetoscopy: A new approach to endoscopic closure of a lumbar skin defect in fetal sheep

Objective: To develop a new endoscopic approach to the correction of a myelomeningocele-like defect in fetal sheep. Methods: The fetuses of 9 pregnant ewes, with an average gestational age of 115 days, were subjected to a 3.0 x 2.0 cm removal of the skin over the lumbar spine, performed through hysterotomy. The uterus was closed, and three 5-mm endoscopic cannulas, without valve mechanisms, were inserted. In the pilot phase (2 animals), we initially worked exclusively in the amniotic fluid space. In the study phase, we partially withdrew the fetus from the amniotic fluid to completely expose its back. By simply allowing air to enter the amniotic cavity (without gas injection), a working space was created using a uterine lift device. The skin around the defect was dissected, and a biosynthetic cellulose material was applied to cover the area. A continuous suture of the skin was performed to completely hide the material. Results: The combined air/fluid space allowed the skin to be successfully closed in 6 out of 7 cases in the study phase. All fetuses were alive at the end of the procedures. Time to complete the endoscopic part of the procedure fell from 3 to 1 h by the end of this series. Premature birth occurred in 2 of the 4 cases allowed to continue with the pregnancy. Conclusion: A new gasless fetoscopic surgery technique was developed as an alternative to current techniques used for fetal endoscopic surgery. Copyright (C) 2008 S. Karger AG, Basel.

Neoskin development in the fetus with the use of a three-layer graft: an animal model for in utero closure of large skin defects

Objective: To assess the ability of a three-layer graft in the closuse of large fetal skin defects. Methods: Ovine fetuses underwent a large (4 x 3 cm) full-thickness skin defect over the lumbar region at 105 days` gestation (term = 140 days). A bilaminar artificial skin was placed over a cellulose interface to cover the defect (3-layer graft). The skin was partially reapproximated with a continuous nylon suture. Pregnancy was allowed to continue and the surgical site was submitted to histopathological analysis at different post-operative intervals. Results: Seven fetuses underwent surgery. One maternal/fetal death occurred, and the remaining 6 fetuses were analyzed. Artificial skin adherence to the wound edges was observed in cases that remained in utero for at least 15 days. Neoskin was present beneath the silicone layer of the bilaminar artificial skin. Conclusions: Our study shows that neoskin can develop in the fetus using a 3-layer graft, including epidermal growth beneath the silicone layer of the bilaminar skin graft. These findings suggest that the fetus is able to reepithelialise even large skin defects. Further experience is necessary to assess the quality of this repair.

Vaccinating the vampire bat Desmodus rotundus against rabies

The objective of this study was to extend the previous work of indirect oral rabies immunization of vampire bats (Desmodus rotundus) maintained in captivity, which demonstrated the immunogenicity of the V-RG vaccine (Vaccinia-Rabies Glycoprotein) and indicated that although the results had been encouraging, a new method for concentrating the vaccine should be tested in order to avoid vaccine loss and increase the survival proportion of bats after rabies challenge. In this study, three groups of seven bats each were tested with vaccine concentrated by ultrafiltration through a cellulose membrane. The vaccine was homogenized in Vaseline paste and applied to the back of one vector bat, which was then reintroduced into its group. A dose of 10(5.0) MICLD50 rabies virus was used by intramuscular route to challenge the bats postvaccination. The survival proportion in the three groups after the challenge was 71.4%, 71.4% and 100%. (c) 2008 Elsevier B.V. All rights reserved.

Evaluation of lignin contents in tropical forages using different analytical methods and their correlations with degradation of insoluble fiber

We compared the lignin contents of tropical forages by different analytical methods and evaluated their correlations with parameters related to the degradation of neutral detergent fiber (NDF). The lignin content was evaluated by five methods: cellulose solubilization in sulfuric acid [Lignin (sa)], oxidation with potassium permanganate [Lignin (pm)], the Klason lignin method (KL), solubilization in acetyl bromide from acid detergent fiber (ABLadf) and solubilization in acetyl bromide from the cell wall (ABLcw). Samples from ten grasses and ten legumes were used. The lignin content values obtained by gravimetric methods were also corrected for protein contamination, and the corrected values were referred to as Lignin (sa)p, Lignin (pm)p and KLp. The indigestible fraction of NDF (iNDF), the discrete lag (LAG) and the fractional rate of degradation (kd) of NDF were estimated using an in vitro assay. Correcting for protein resulted in reductions (P < 0.05) in the lignin contents as measured by the Lignin (sa), Lignin (pm) and, especially, the KL methods. There was an interaction (P < 0.05) of analytical method and forage group for lignin content. In general, LKp method provided the higher (P < 0.05) lignin contents. The estimates of lignin content obtained by the Lignin (sa)p, Lignin (pm)p and LKp methods were associated (P > 0.05) with all of the NDF degradation parameters. However, the strongest correlation coefficients for all methods evaluated were obtained with Lignin (pm)p and KLp. The lignin content estimated by the ABLcw method did not correlate (P > 0.05) with any parameters of NDF degradation. There was a correlation (P < 0.05) between the lignin content estimated by the ABLadf method and iNDF content. Nonetheless, this correlation was weaker than those found with gravimetric methods. From these results, we concluded that the gravimetric methods produce residues that are contaminated by nitrogenous compounds. Adjustment for these contaminants is suggested, particularly for the KL method, to express lignin content with greater accuracy. The relationships between lignin content measurements and NDF degradation parameters can be better determined using KLp and Lignin (pm)p methods. (C) 2011 Elsevier B.V. All rights reserved.