Electrospun nanofibrous scaffolds increase the efficacy of stem cell-mediated therapy of surgically resected glioblastoma

Engineered stem cell (SC)-based therapy holds enormous promise for treating the incurable brain cancer glioblastoma (GBM). Retaining the cytotoxic SCs in the surgical cavity after GBM resection is one of the greatest challenges to this approach. Here, we describe a biocompatible electrospun nanofibrous scaffold (bENS) implant capable of delivering and retaining tumor-homing cytotoxic stem cells that suppress recurrence of post-surgical GBM. As a new approach to GBM therapy, we created poly(l-lactic acid) (PLA) bENS bearing drug-releasing human mesenchymal stem cells (hMSCs). We discovered that bENS-based implant increased hMSC retention in the surgical cavity 5-fold and prolonged persistence 3-fold compared to standard direct injection using our mouse model of GBM surgical resection/recurrence. Time-lapse imaging showed cytotoxic hMSC/bENS treatment killed co-cultured human GBM cells, and allowed hMSCs to rapidly migrate off the scaffolds as they homed to GBMs. In vivo, bENS loaded with hMSCs releasing the anti-tumor protein TRAIL (bENSsTR) reduced the volume of established GBM xenografts 3-fold. Mimicking clinical GBM patient therapy, lining the post-operative GBM surgical cavity with bENSsTR implants inhibited the re-growth of residual GBM foci 2.3-fold and prolonged post-surgical median survival from 13.5 to 31 days in mice. These results suggest that nanofibrous-based SC therapies could be an innovative new approach to improve the outcomes of patients suffering from terminal brain cancer

Molino de martillos vs. Molinos de rodillo si efectos de l a molienda del cereal principal de la dieta sobre la productividad y la calidad del huevo en gallinas ponedoras rubias.

La influencia del cereal principal de la dieta y el tipo de molienda sobre los parámetros productivos y la calidad del huevo fue estudiada en 420 ponedoras rubias de la estirpe Hy -Line en el período 24 a 59 semanas de vida. Se utilizó un diseño completamente al azar con 6 tratamientos ordenados factorialmente bajo un esquema 3 x 2, con 3 tipos de cereales (cebada, trigo blando y maíz) y dos tipos de moliendas (molino de martillo o molino de rodillos). Cada tratamiento fue replicado 7 veces y la unidad experimental consistió una jaula enriquecida con 10 gallinas. Las variables productivas de las aves fueron analizadas en periodos de 28 días y las variables de calidad del huevo fueron medidas en la semana 40 y 56 de vida respectivamente. El tamaño medio de partícula fue mayor en las dietas basadas en cebada que en las dietas basada en trigo o maíz, siendo estas diferencias más pronunciadas cuando se utilizó el martillo de rodillo para moler las dietas. La proporción de partículas menores de 2500 μm disminuyó con la utilización del molino de rodillo respecto al molino de martillo (13.2% vs. 6.0%). Teniendo en cuenta el periodo global del experimento, el consumo medio diario fue mayor en las gallinas que consumieron tanto trigo como maíz respecto a las que consumieron cebada (110.8 y 110.7 vs. 109.7 g/d; P< 0.05). Varias nteracciones fueron detectadas entre el cereal principal de la dieta y el tipo de molino utilizado, así el consumo medio diario (P< 0.01) y el porcentaje de puesta (P=0.09) fue similar en todas las dietas cuando el molino de martillo fue utilizado, sin embargo, ambas variables empeoraron cuando el molino de rodillo fue utilizado en la dieta basada en cebada respecto a la basada en trigo o maíz. A pesar de estos efectos, tanto en el consumo diario como en la puesta, ninguna de las variables productivas restantes fue afectada por el tratamiento. En cuanto a las variables relacionadas con la calidad de huevo, ninguna de las variables estudiadas fue afectada por el tratamiento. Con estas premisas, podemos concluir que el molino de rodillo puede utilizarse de forma exitosa para moler dietas basadas en cereales, especialmente trigo y maíz. Sin embargo, el molino de rodillo quizá no se adecuado para moler cereales con un porcentaje de fibra elevado como es el caso de la cebada

Stereospecific conversion of alcohols into pinacol boronic esters using lithiation-borylation methodology with pinacolborane

The synthesis of primary and secondary pinacol boronic esters via lithiation–borylation of carbamates and benzoates with pinacolborane is described. This new protocol enables the highly selective synthesis of enantioenriched and geometrically defined boronic esters that cannot otherwise be accessed by alternative methodologies

Capacitative calcium influx and proliferation of human osteoblastic-like MG-63 cells

Adult bone tissue is continuously being remodelled and bone mass is maintained by a balance between osteoclastic bone resorption and osteoblastic bone formation. Alteration of osteoblastic cell proliferation may account in part for lack of balance between these two processes in bone loss of osteoporosis. There is calcium (Ca2+) control in numerous cellular functions; however, involvement of capacitative Ca2+ entry (CCE) in proliferation of bone cells is less well investigated. OBJECTIVES: The study described here was aimed to investigate roles of CCE in the proliferation of osteoblast-like MG-63 cells. MATERIALS AND METHODS: Pharmacological characterizations of CCE were undertaken in parallel, with evaluation of the expression of transient receptor potential canonical (TRPC) channels and of cell proliferation. RESULTS: Intracellular Ca2+ store depletion by thapsigargin induced CCE in MG-63 cells; this was characterized by a rapid transient increase of intracellular Ca2+ followed by significant CCE, induced by conditions that stimulated cell proliferation, namely serum and platelet-derived growth factor. Inhibitors of store-operated Ca2+ channels (2-APB and SKF-96365) prevented CCE, while voltage-dependent Ca2+ channel blockers had no effect. Expression of various TRPC channels was shown in the cells, some having been shown to be responsible for CCE. Voltage-dependent Ca2+ channel blockers had no effect on osteoblast proliferation while thapsigargin, 2-APB and SKF-96395, inhibited it. Cell cycle analysis showed that 2-APB and SKF-96395 lengthen the S and G2/M phases, which would account for the reduction in cell proliferation. CONCLUSIONS: Our results indicate that CCE, likely attributed to the activation of TRPCs, might be the main route for Ca2+ influx involved in osteoblast proliferation

Genomic and biochemical approaches in the discovery of mechanisms for selective neuronal vulnerability to oxidative stress

<p>Abstract</p> <p>Background</p> <p>Oxidative stress (OS) is an important factor in brain aging and neurodegenerative diseases. Certain neurons in different brain regions exhibit selective vulnerability to OS. Currently little is known about the underlying mechanisms of this selective neuronal vulnerability. The purpose of this study was to identify endogenous factors that predispose vulnerable neurons to OS by employing genomic and biochemical approaches.</p> <p>Results</p> <p>In this report, using <it>in vitro </it>neuronal cultures, <it>ex vivo </it>organotypic brain slice cultures and acute brain slice preparations, we established that cerebellar granule (CbG) and hippocampal CA1 neurons were significantly more sensitive to OS (induced by paraquat) than cerebral cortical and hippocampal CA3 neurons. To probe for intrinsic differences between <it>in vivo </it>vulnerable (CA1 and CbG) and resistant (CA3 and cerebral cortex) neurons under basal conditions, these neurons were collected by laser capture microdissection from freshly excised brain sections (no OS treatment), and then subjected to oligonucleotide microarray analysis. GeneChip-based transcriptomic analyses revealed that vulnerable neurons had higher expression of genes related to stress and immune response, and lower expression of energy generation and signal transduction genes in comparison with resistant neurons. Subsequent targeted biochemical analyses confirmed the lower energy levels (in the form of ATP) in primary CbG neurons compared with cortical neurons.</p> <p>Conclusion</p> <p>Low energy reserves and high intrinsic stress levels are two underlying factors for neuronal selective vulnerability to OS. These mechanisms can be targeted in the future for the protection of vulnerable neurons.</p

Enantiospecific sp(2)-sp(3) coupling of secondary and tertiary boronic esters

The cross-coupling of boronic acids and related derivatives with sp² electrophiles (the Suzuki–Miyaura reaction) is one of the most powerful C–C bond formation reactions in synthesis, with applications that span pharmaceuticals, agrochemicals and high-tech materials. Despite the breadth of its utility, the scope of this Nobel prize-winning reaction is rather limited when applied to aliphatic boronic esters. Primary organoboron reagents work well, but secondary and tertiary boronic esters do not (apart from a few specific and isolated examples). Through an alternative strategy, which does not involve using transition metals, we have discovered that enantioenriched secondary and tertiary boronic esters can be coupled to electron-rich aromatics with essentially complete enantiospecificity. As the enantioenriched boronic esters are easily accessible, this reaction should find considerable application, particularly in the pharmaceutical industry where there is growing awareness of the importance of, and greater clinical success in, creating biomolecules with three-dimensional architectures