In vitro differentiation of bone marrow derived porcine mesenchymal stem cells to endothelial cells

Mesenchymal stem cells (MSCs) hold potential for the regeneration of damaged tissues in cardiovascular diseases. In this study, we investigated the potential of porcine MSCs to differentiate into endothelial cells (ECs) in vitro. The cultured bone marrow‐derived cells were CD11b^–CD34^–CD44⁺CD45^–CD90⁺ and showed mesodermal lineage differentiation, which is characteristic of MSCs. The MSCs were induced to differentiate into ECs using endothelial growth medium (EGM), with and without high concentrations of VEGF (EGM + VEGF; 50 ng/ml). Endothelial basal medium (EBM) without growth factors served as the control. The EC differentiation was assessed by the presence of vWF, ability to take up acetylated LDL, in vitro angiogenesis assay, flow cytometry and qPCR of EC markers vWF, VE‐cadherin, PECAM‐1, VEGF‐R1 and VEGF‐R2 after 10 days of stimulation. Cells cultured in EGM + VEGF medium demonstrated higher amounts of DiI‐AcLDL‐positive cells and enhanced the presence of vWF (90%), VE‐Cadherin‐ (60%) and PECAM‐1 (48%)‐positive cells, than in EBM. These cells showed profuse sprouting of capillary tubes and closed polygon formation in the angiogenesis assay. There was 1.5–2‐fold increase in the mRNA expression of endothelial markers in the cells stimulated with EGM + VEGF medium when compared to control. The results demonstrate the ability of porcine MSCs to differentiate into ECs under in vitro inducing conditions. The differentiated cells would provide new options for re‐endothelialization following interventional procedures and tissue engineering. Copyright © 2012 John Wiley & Sons, Ltd.     

PhRMA CPCDC initiative on predictive models of human pharmacokinetics,part 3: Comparative assessement of prediction methods of human clearance

The objective of this study was to evaluate the performance of various allometric and in vitro–in vivo extrapolation (IVIVE) methodologies with and without plasma protein binding corrections for the prediction of human intravenous (i.v.) clearance (CL). The objective was also to evaluate the IVIVE prediction methods with animal data. Methodologies were selected from the literature. Pharmaceutical Research and Manufacturers of America member companies contributed blinded datasets from preclinical and clinical studies for 108 compounds, among which 19 drugs had i.v. clinical pharmacokinetics data and were used in the analysis. In vivo and in vitro preclinical data were used to predict CL by 29 different methods. For many compounds, in vivo data from only two species (generally rat and dog) were available and/or the required in vitro data were missing, which meant some methods could not be properly evaluated. In addition, 66 methods of predicting oral (p.o.) area under the curve (AUC_p.o.) were evaluated for 107 compounds using rational combinations of i.v. CL and bioavailability (F), and direct scaling of observed p.o. CL from preclinical species. Various statistical and outlier techniques were employed to assess the predictability of each method. Across methods, the maximum success rate in predicting human CL for the 19 drugs was 100%, 94%, and 78% of the compounds with predictions falling within 10‐fold, threefold, and twofold error, respectively, of the observed CL. In general, in vivo methods performed slightly better than IVIVE methods (at least in terms of measures of correlation and global concordance), with the fu intercept method and two‐species‐based allometry (rat–dog) being the best performing methods. IVIVE methods using microsomes (incorporating both plasma and microsomal binding) and hepatocytes (not incorporating binding) resulted in 75% and 78%, respectively, of the predictions falling within twofold error. IVIVE methods using other combinations of binding assumptions were much less accurate. The results for prediction of AUC_p.o. were consistent with i.v. CL. However, the greatest challenge to successful prediction of human p.o. CL is the estimate of F in human. Overall, the results of this initiative confirmed predictive performance of common methodologies used to predict human CL. © 2011 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:4090–4110, 2011     

Spontaneous Rupture of a Giant Hepatic Hemangioma-Report of a Case

Hemangioma is the commonest benign hepatic neoplasm. Most cases are asymptomatic. Spontaneous rupture is rare (1–4%). Only 34 cases have been reported in adults. None had history of trauma. We report a case, the first from India of spontaneous rupture of a giant hepatic hemangioma, in a 25 year old male presenting with acute abdomen. He underwent right hepatectomy. Histopathology suggested cavernous hemangioma.     

Human congenital myopathy actin mutants cause myopathy and alter Z-disc structure in Drosophila flight muscle

Over 190 mutations in the human skeletal muscle α-actin gene, ACTA1 cause congenital actin myopathies. We transgenically expressed six different mutant actins, G15R, I136M, D154N, V163L, V163M and D292V in Drosophila indirect flight muscles and investigated their effects in flies that express one wild type and one mutant actin copy. All the flies were flightless, and the IFMs showed incomplete Z-discs, disorganised actin filaments and ‘zebra bodies’. No differences in levels of sarcomeric protein expression were observed, but tropomodulin staining was somewhat disrupted in D164N, V163L, G15R and V163M heterozygotes. A single copy of D292V mutant actin rescued the hypercontractile phenotypes caused by TnI and TnT mutants, suggesting that the D292V mutation interferes with thin filament regulation. Our results show that expression of actin mutations homologous to those in humans in the indirect flight muscles of Drosophila disrupt sarcomere organisation, with somewhat similar phenotypes to those observed in humans. Using Drosophila to study actin mutations may help aid our understanding of congential myopathies caused by actin mutations.     

Barriers and facilitators to growth monitoring and promotion in Nepal: Household,health worker and female community health volunteer perceptions

Growth monitoring and promotion (GMP) is both a service for diagnosing inadequate child growth in its earliest stages and a delivery platform for nutrition counselling. The widespread use of GMP services in developing countries has the potential to substantially reduce persistent child undernutrition through early diagnosis and by linking caregivers and their children to key health and nutrition services. However, researchers have questioned the effectiveness of GMP services, which are frequently undermined by underdeveloped health systems and inconsistent implementation. This analysis examined both supply‐ and demand‐side factors for GMP utility in Nepal from the perspectives of beneficiaries and service providers, particularly focusing on three components of GMP: growth assessment, analysis of growth status and counselling. The most common factors influencing GMP uptake included beneficiaries' perceptions of the relative importance of GMP and the knowledge and skill of frontline workers. Both providers and beneficiaries viewed GMP as a secondary health and nutrition activity and therefore less important than curative services. We found deficits in GMP‐related knowledge and skills among providers (i.e. health workers and female community health volunteers), as well as indications of poor training quality and coverage. Furthermore, we found variation in GMP utilization by maternal age, education and residency (alone, nuclear or extended), as well as household socio‐economic well‐being and rurality. This study is the first to assess factors influencing both beneficiaries and service providers for GMP utilization. Further research is needed to explore the implementation of improved GMP protocols and to evaluate facility‐level implementation barriers.     

Methods for estimating neural firing rates,and their application to brain–machine interfaces

Neural spike trains present analytical challenges due to their noisy, spiking nature. Many studies of neuroscientific and neural prosthetic importance rely on a smoothed, denoised estimate of a spike train’s underlying firing rate. Numerous methods for estimating neural firing rates have been developed in recent years, but to date no systematic comparison has been made between them. In this study, we review both classic and current firing rate estimation techniques. We compare the advantages and drawbacks of these methods. Then, in an effort to understand their relevance to the field of neural prostheses, we also apply these estimators to experimentally gathered neural data from a prosthetic arm-reaching paradigm. Using these estimates of firing rate, we apply standard prosthetic decoding algorithms to compare the performance of the different firing rate estimators, and, perhaps surprisingly, we find minimal differences. This study serves as a review of available spike train smoothers and a first quantitative comparison of their performance for brain–machine interfaces.     

Dabrafenib-induced neutrophilic panniculitis in a child undergoing dual BRAF-MEK inhibitor therapy for glioblastoma multiforme

BRAF inhibitor-induced neutrophilic panniculitis is a rare event that is well-characterized in adults undergoing therapy for metastatic melanoma. To date, there are very few reports of this event in children undergoing BRAF inhibitor therapy for low-grade gliomas, all of which were seen with vemurafenib. We report a case of dabrafenib-induced neutrophilic panniculitis in a 9-year-old girl that manifested within several weeks of initiating dual BRAF-MEK inhibitor therapy for glioblastoma multiforme. This case highlights neutrophilic panniculitis as a side effect of dabrafenib in children and serves as a reminder to consider cutaneous side effects of BRAF inhibitors as they are increasingly used to treat children with primary brain tumors.     

Nevus psiloliparus: Newly described histopathological features from transverse sections

Nevus psiloliparus is a rare fatty tissue nevus that is a marker for encephalocraniocutaneous lipomatosis, a neurocutaneous syndrome with ocular and central nervous system anomalies. Clinically, nevus psiloliparus is often described as a congenital alopecia and appears as an irregularly shaped, circumscribed area of alopecia on the scalp. Histopathology demonstrates a near-complete absence of mature hair follicles with preservation of arrector pili muscles and mature adipocytes within the dermis. The pathogenesis of nevus psiloliparus may be related to mosaic mutations in fibroblast growth factor receptor 1. Herein we report the histopathological features of a nevus psiloliparus in an 11-year-old girl diagnosed from transverse sections, which show “shadow” follicular units characterized by columns of loosely arranged collagen and a relative paucity of elastic fibers.     

Maté consumption and the risk of squamous cell esophageal cancer in uruguay.

A retrospective hospital-based case-control study was carried out at the Oncology Institute of Montevideo, Uruguay, to investigate the role of maté consumption in esophageal cancer risk. The study included 344 cases with squamous cell carcinoma of the esophagus and 469 controls recruited between January 1988 and August 2000. Maté consumption was significantly associated with an increased risk of developing esophageal cancer and showed a clear dose response, with a relative risk of 2.84 [95% confidence interval (CI), 1.41-5.73] for those drinking more than 1 liter/day of maté as compared with nondrinkers. Subjects who self-reported drinking maté at a very hot temperature had an almost 2-fold increase in risk [odds ratio (OR), 1.87; 95% CI, 1.17-3.00] compared with those drinking warm to hot maté, after adjusting for cumulative consumption of maté. Maté amount and temperature were observed to have independent effects and, although no departure from multiplicativity was observed between the two covariates, those drinking more than 1 liter/day of maté at a very hot temperature had a 3-fold increase in risk (OR, 2.95; 95% CI, 1.30-6.74) compared with those drinking less than 0.5 liter/day of maté at a warm to hot temperature. Subjects with high cumulative exposure to maté in the presence of low alcohol and tobacco exposures presented a lower-risk estimate (OR, 1.52; 95% CI, 0.88-2.62), whereas those with high cumulative exposures to maté, alcohol, and tobacco presented a 7-fold increase in esophageal cancer risk (OR, 7.10; 95% CI, 3.75-13.46). The population-attributable fraction as a result of maté consumption was calculated to be 53%, of which the sole effect of amount and temperature was 14.8 and 12.6% respectively, and 14.9% was attributable to high maté consumption at high temperature.