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排序方式: 共有270条查询结果,搜索用时 15 毫秒
91.
The lateral geniculate nuclear complex of albino rats was investigated with respect to the development of neurotransmitters/neuromodulators
such as glutamate, cholecystokinin and vasoactive intestinal polypeptide at gestational day 18, various postnatal age periods
and in the adult using immunohistochemical methods. The study shows the unequivocal presence of and the sequential changes
in the profile of glutamate while cholecystokinin and vasoactive intestinal polypeptide are not demonstrable at any of the
age periods. Glutamate is seen both in the cells and fibres from 40 postnatal day onwards and immunoreactivity is more intense
in the adult. The findings are discussed with relevance to the role of neurotransmitters in development. 相似文献
92.
93.
Cheung CT Singh R Yoon AR Hasan MK Yaguchi T Kaul SC Yun CO Wadhwa R 《Cell death and differentiation》2011,18(4):589-601
Collaborator of ARF (CARF) was cloned as an ARF-interacting protein and shown to regulate the p53-p21(WAF1)-HDM2 pathway, which is central to tumor suppression via senescence and apoptosis. We had previously reported that CARF inhibition in cancer cells led to polyploidy and caspase-dependent apoptosis, however, the mechanisms governing this phenomenon remained unknown. Thus, we examined various cell death and survival pathways including the mitochondrial stress, ataxia telangiectasia mutated (ATM)-ATR, Ras-MAP kinase and retinoblastoma cascades. We found that CARF is a pleiotropic regulator with widespread effects; its suppression affected all investigated pathways. Most remarkably, it protected the cells against genotoxicity; CARF knockdown elicited DNA damage response as evidenced by increased levels of phosphorylated ATM and γH2AX, leading to induction of mitotic arrest and eventual apoptosis. We also show that the CARF-silencing-induced apoptosis in vitro translates to in vivo. In a human tumor xenograft mouse model, treatment of developing tumors with short hairpin RNA (shRNA) against CARF via an adenovirus carrier induced complete suppression of tumor growth, suggesting that CARF shRNA is a strong candidate for an anticancer reagent. We demonstrate that CARF has a vital role in genome preservation and tumor suppression and CARF siRNA is an effective novel cancer therapeutic agent. 相似文献
94.
Sharma NN Sharma M Bhalla TC 《Journal of industrial microbiology & biotechnology》2011,38(9):1235-1243
Nitrilase of Nocardia globerula NHB-2 was induced by short-chain aliphatic nitriles (valeronitrile > isobutyronitrile > butyronitrile > propionitrile) and
exhibited activity towards aromatic nitriles (benzonitrile > 3-cyanopyridine > 4-cyanopyridine > m-tolunitrile > p-tolunitrile). Hyperinduction of nitrilase (6.67 U mgDCW−1, 18.7 U mL−1) was achieved in short incubation time (30 h, 30°C) through multiple feeding of isobutyronitrile in the growth medium. The
nitrilase of this organism exhibits both substrate and product inhibition effects. In a fed batch reaction at 1 L scale using
hyperinduced resting cells corresponding to 10 U mL−1 nitrilase activity (1.5 mgDCW mL−1), a total of 123.11 g nicotinic acid was produced at a rate of 24 g h−1 gDCW−1. 相似文献
95.
Krishnan N Malaga W Constant P Caws M Tran TH Salmons J Nguyen TN Nguyen DB Daffé M Young DB Robertson BD Guilhot C Thwaites GE 《PloS one》2011,6(9):e23870
The six major genetic lineages of Mycobacterium tuberculosis are strongly associated with specific geographical regions, but their relevance to bacterial virulence and the clinical consequences of infection are unclear. Previously, we found that in Vietnam, East Asian/Beijing and Indo-Oceanic strains were significantly more likely to cause disseminated tuberculosis with meningitis than those from the Euro-American lineage. To investigate this observation we characterised 7 East Asian/Beijing, 5 Indo-Oceanic and 6 Euro-American Vietnamese strains in bone-marrow-derived macrophages, dendritic cells and mice. East Asian/Beijing and Indo-Oceanic strains induced significantly more TNF-α and IL-1β from macrophages than the Euro-American strains, and East Asian/Beijing strains were detectable earlier in the blood of infected mice and grew faster in the lungs. We hypothesised that these differences were induced by lineage-specific variation in cell envelope lipids. Whole lipid extracts from East Asian/Beijing and Indo-Oceanic strains induced higher concentrations of TNF-α from macrophages than Euro-American lipids. The lipid extracts were fractionated and compared by thin layer chromatography to reveal a distinct pattern of lineage-associated profiles. A phthiotriol dimycocerosate was exclusively produced by East Asian/Beijing strains, but not the phenolic glycolipid previously associated with the hyper-virulent phenotype of some isolates of this lineage. All Indo-Oceanic strains produced a unique unidentified lipid, shown to be a phenolphthiocerol dimycocerosate dependent upon an intact pks15/1 for its production. This was described by Goren as the 'attenuation indictor lipid' more than 40 years ago, due to its association with less virulent strains from southern India. Mutation of pks15/1 in a representative Indo-Oceanic strain prevented phenolphthiocerol dimycocerosate synthesis, but did not alter macrophage cytokine induction. Our findings suggest that the early interactions between M. tuberculosis and host are determined by the lineage of the infecting strain; but we were unable to show these differences are driven by lineage-specific cell-surface expressed lipids. 相似文献
96.
Wesley S. Bond Lalita Wadhwa Laszlo Perlaky Rebecca L. Penland Mary Y. Hurwitz Richard L. Hurwitz Patricia Ch��vez-Barrios 《Journal of visualized experiments : JoVE》2011,(54)
Culturing retinoblastoma tumor cells in defined stem cell media gives rise to primary tumorspheres that can be grown and maintained for only a limited time. These cultured tumorspheres may exhibit markedly different cellular phenotypes when compared to the original tumors. Demonstration that cultured cells have the capability of forming new tumors is important to ensure that cultured cells model the biology of the original tumor. Here we present a protocol for propagating human retinoblastoma tumors in vivo using Rag2-/- immune deficient mice. Cultured human retinoblastoma tumorspheres of low passage or cells obtained from freshly harvested human retinoblastoma tumors injected directly into the vitreous cavity of murine eyes form tumors within 2-4 weeks. These tumors can be harvested and either further passaged into murine eyes in vivo or grown as tumorspheres in vitro. Propagation has been successfully carried out for at least three passages thus establishing a continuing source of human retinoblastoma tissue for further experimentation. Wesley S. Bond and Lalita Wadhwa are co-first authors. 相似文献
97.
Background and Objectives
India has the highest annual number of maternal deaths of any country. As obstetric hemorrhage is the leading cause of maternal death in India, numerous efforts are under way to promote access to skilled attendance at birth and emergency obstetric care. Current initiatives also seek to increase access to active management of the third stage of labor for postpartum hemorrhage prevention, particularly through administration of an uterotonic after delivery. However, prior research suggests widespread inappropriate use of uterotonics at facilities and in communities–for example, without adequate monitoring or referral support for complications. This qualitative study aimed to document health providers’ and community members’ current knowledge, attitudes, and practices regarding uterotonic use during labor and delivery in India’s Karnataka state.Methods
140 in-depth interviews were conducted from June to August 2011 in Bagalkot and Hassan districts with physicians, nurses, recently delivered women, mothers-in-law, traditional birth attendants (dais), unlicensed village doctors, and chemists (pharmacists).Results
Many respondents reported use of uterotonics, particularly oxytocin, for labor augmentation in both facility-based and home-based deliveries. The study also identified contextual factors that promote inappropriate uterotonic use, including high value placed on pain during labor; perceived pressure to provide or receive uterotonics early in labor and delivery, perhaps leading to administration of uterotonics despite awareness of risks; and lack of consistent and correct knowledge regarding safe storage, dosing, and administration of oxytocin.Conclusions
These findings have significant implications for public health programs in a context of widespread and potentially increasing availability of uterotonics. Among other responses, efforts are needed to improve communication between community members and providers regarding uterotonic use during labor and delivery and to target training and other interventions to address identified gaps in knowledge and ensure that providers and pharmacists have up-to-date information regarding proper usage of uterotonic drugs. 相似文献98.
Chapla Agarwal Ritambhara Wadhwa Gagan Deep David Biedermann Radek Ga?ák Vladimír K?en Rajesh Agarwal 《PloS one》2013,8(3)
Silybin or silibinin, a flavonolignan isolated from Milk thistle seeds, is one of the popular dietary supplements and has been extensively studied for its antioxidant, hepatoprotective and anti-cancer properties. We have envisioned that potency of silybin could be further enhanced through suitable modification/s in its chemical structure. Accordingly, here, we synthesized and characterized a series of silybin derivatives namely 2,3-dehydrosilybin (DHS), 7-O-methylsilybin (7OM), 7-O-galloylsilybin (7OG), 7,23-disulphatesilybin (DSS), 7-O-palmitoylsilybin (7OP), and 23-O-palmitoylsilybin (23OP); and compared their anti-cancer efficacy using human bladder cancer HTB9, colon cancer HCT116 and prostate carcinoma PC3 cells. In all the 3 cell lines, DHS, 7OM and 7OG demonstrated better growth inhibitory effects and compared to silybin, while other silybin derivatives showed lesser or no efficacy. Next, we prepared the optical isomers (A and B) of silybin, DHS, 7OM and 7OG, and compared their anti-cancer efficacy. Isomers of these three silybin derivatives also showed better efficacy compared with respective silybin isomers, but in each, there was no clear cut silybin A versus B isomer activity preference. Further studies in HTB cells found that DHS, 7OM and 7OG exert better apoptotic activity than silibinin. Clonogenic assays in HTB9 cells further confirmed that both the racemic mixtures as well as pure optical isomers of DHS, 7OM and 7OG were more effective than silybin. Overall, these results clearly suggest that the anti-cancer efficacy of silybin could be significantly enhanced through structural modifications, and identify strong anti-cancer efficacy of silybin derivatives, namely DHS, 7OM, and 7OG, signifying that their efficacy and toxicity should be evaluated in relevant pre-clinical cancer models in rodents. 相似文献
99.
Neuroblastoma is an aggressive childhood disease of the sympathetic nervous system. Treatments are often ineffective and have serious side effects. Conventional therapy of neuroblastoma includes the differentiation agents. Unlike chemo-radiotherapy, differentiation therapy shows minimal side effects on normal cells, because normal non-malignant cells are already differentiated. Keeping in view the limited toxicity of Withania somnifera (Ashwagandha), the current study was aimed to investigate the efficacy of Ashwagandha water extract (ASH-WEX) for anti-proliferative potential in neuroblastoma and its underlying signalling mechanisms. ASH-WEX significantly reduced cell proliferation and induced cell differentiation as indicated by morphological changes and NF200 expression in human IMR-32 neuroblastoma cells. The induction of differentiation was accompanied by HSP70 and mortalin induction as well as pancytoplasmic translocation of the mortalin in ASH-WEX treated cells. Furthermore, the ASH-WEX treatment lead to induction of neural cell adhesion molecule (NCAM) expression and reduction in its polysialylation, thus elucidating its anti-migratory potential, which was also supported by downregulation of MMP 2 and 9 activity. ASH-WEX treatment led to cell cycle arrest at G0/G1 phase and increase in early apoptotic population. Modulation of cell cycle marker Cyclin D1, anti-apoptotic marker bcl-xl and Akt-P provide evidence that ASH-WEX may prove to be a promising phytotherapeutic intervention in neuroblatoma related malignancies. 相似文献
100.
Tania Sanyal Vivek Kumar Tapas Chandra Nag Suman Jain Vishnu Sreenivas Shashi Wadhwa 《PloS one》2013,8(7)
Prenatal auditory stimulation in chicks with species-specific sound and music at 65 dB facilitates spatial orientation and learning and is associated with significant morphological and biochemical changes in the hippocampus and brainstem auditory nuclei. Increased noradrenaline level due to physiological arousal is suggested as a possible mediator for the observed beneficial effects following patterned and rhythmic sound exposure. However, studies regarding the effects of prenatal high decibel sound (110 dB; music and noise) exposure on the plasma noradrenaline level, synaptic protein expression in the hippocampus and spatial behavior of neonatal chicks remained unexplored. Here, we report that high decibel music stimulation moderately increases plasma noradrenaline level and positively modulates spatial orientation, learning and memory of one day-old chicks. In contrast, noise at the same sound pressure level results in excessive increase of plasma noradrenaline level and impairs the spatial behavior. Further, to assess the changes at the molecular level, we have quantified the expression of functional synapse markers: synaptophysin and PSD-95 in the hippocampus. Compared to the controls, both proteins show significantly increased expressions in the music stimulated group but decrease in expressions in the noise group. We propose that the differential increase of plasma noradrenaline level and altered expression of synaptic proteins in the hippocampus are responsible for the observed behavioral consequences following prenatal 110 dB music and noise stimulation. 相似文献