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541.
Tumor necrosis factor α (TNF-α) is an essential player in infection with Leishmania, controlling inflammatory lesion and parasite killing. We recently have shown the leishmanicidal activity of transmembrane form of TNF (mTNF) derived from allogeneic natural killer (NK) cells in experimental visceral leishmaniasis. Allogeneic macrophages and human monocytes derived mTNF has significantly higher antileishmanial activity compared to allogeneic NK cells. Unlike NK cells, syngeneic macrophages also possess antileishmanial activity, although degree of activity is significantly less compared to allogeneic macrophages. Cellular therapy by intravenous transfer of allogeneic macrophages enhances leishmanicidal effect against the established infection in susceptible animal by reducing the splenic parasite burden to 28.3 ± 4.71 × 105 compared to 256.00 ± 17.36 × 105 in control group. In vivo treatment with anti-mouse TNF-α reduces the therapeutic efficacy of the allogeneic macrophages by increasing the parasite load in spleen of infected mice. These results demonstrated that allogeneic and xenogeneic macrophages induce cytokine mediated protective mechanism against infected macrophages via TNF-α in vitro and, possibly in vivo. The macrophage mediated protective role in absence of T cell help demonstrate an unique property of the mononuclear phagocytes in controlling infection and inflammation in visceral leishmaniasis, despite being acts as a host cell for the same parasite. 相似文献
542.
A genetic model is discussed for recessively inherited disorders that do not follow a single-locus Mendelian pattern of inheritance. Further complexity arising from variable age of onset is also discussed. Methods of statistical analysis of family data using the likelihood principle are described for such complex disorders. The methods are exemplified using data on families of prelingual deafness and vitiligo. 相似文献
543.
Corey A. Theriot Rachael C. Casey Valerie C. Moore Linsey Mitchell Julia O. Reynolds Madeline Burgoyne Ranga Partha Janice L. Huff Jodie L. Conyers Antony Jeevarajan Honglu Wu 《Radiation and environmental biophysics》2010,49(3):437-445
In this study, the ability of the C60 fullerene derivative DF-1 to protect radiosensitive cells from the effects of high doses of gamma irradiation was examined. Earlier reports of DF-1’s lack of toxicity in these cells were confirmed, and DF-1 was also observed to protect both human lymphocytes and rat intestinal crypt cells against radiation-induced cell death. We determined that DF-1 protected both cell types against radiation-induced DNA damage, as measured by inhibition of micronucleus formation. DF-1 also reduced the levels of reactive oxygen species in the crypt cells, a unique capability of fullerenes because of their enhanced reactivity toward electron-rich species. The ability of DF-1 to protect against the cytotoxic effects of radiation was comparable to that of amifostine, another ROS-scavenging radioprotector. Interestingly, localization of fluorescently labeled DF-1 in fibroblast was observed throughout the cell. Taken together, these results suggest that DF-1 provides powerful protection against several deleterious cellular consequences of irradiation in mammalian systems including oxidative stress, DNA damage, and cell death. 相似文献
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546.
Partha Pratim Roy 《Molecular simulation》2013,39(11):887-905
Pharmacophore mapping, molecular docking and quantitative structure–activity relationship (QSAR) studies were carried out for a structurally diverse set of 48 compounds as CYP2B6 inhibitors. The generated best pharmacophore hypotheses from the three methods of conformer generation (FAST, BEST and conformer algorithm based on energy screening and recursive buildup) indicate the importance of two features, namely, hydrogen bond acceptor [electron-rich centre] and ring aromaticity. The distance between the two centres of the important features for ideal inhibitors varied from 5.82 to 6.03 Å. The chemometric tools used for the QSAR analysis were genetic function approximation (GFA) and genetic partial least squares. The developed QSAR models indicate the importance of an electron-rich centre, size of molecule, impact of branching and ring system and distribution of charges in the molecular surface. The docking study confirms the importance of an electron-rich centre for binding with the iron atom of the cytochrome enzyme. A GFA model with spline option was found to be the best model based on internal validation as well as the r 2 m (overall) criterion (Q 2 = 0.772, r 2 m (overall) = 0.774). According to the external prediction statistics (R 2 pred = 0.876), another GFA-derived model with spline option outperforms the remaining models. 相似文献
547.
Malcolm Stein IV Chien-Fan Chen Daniel J. Robles Christopher Rhodes Partha P. Mukherjee 《Journal of visualized experiments : JoVE》2016,(108)
Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational analysis. Testing of lithium-ion batteries in an academic setting has taken on several forms, but at the most basic level lies the coin cell construction. In traditional LIB electrode preparation, a multi-phase slurry composed of active material, binder, and conductive additive is cast out onto a substrate. An electrode disc can then be punched from the dried sheet and used in the construction of a coin cell for electrochemical evaluation. Utilization of the potential of the active material in a battery is critically dependent on the microstructure of the electrode, as an appropriate distribution of the primary components are crucial to ensuring optimal electrical conductivity, porosity, and tortuosity, such that electrochemical and transport interaction is optimized. Processing steps ranging from the combination of dry powder, wet mixing, and drying can all critically affect multi-phase interactions that influence the microstructure formation. Electrochemical probing necessitates the construction of electrodes and coin cells with the utmost care and precision. This paper aims at providing a step-by-step guide of non-aqueous electrode processing and coin cell construction for lithium-ion batteries within an academic setting and with emphasis on deciphering the influence of drying and calendaring. 相似文献
548.
Mahtab Hassanpourfard Xiaohui Sun Amin Valiei Partha Mukherjee Thomas Thundat Yang Liu Aloke Kumar 《Journal of visualized experiments : JoVE》2014,(90)
Several bacterial species possess the ability to attach to surfaces and colonize them in the form of thin films called biofilms. Biofilms that grow in porous media are relevant to several industrial and environmental processes such as wastewater treatment and CO2 sequestration. We used Pseudomonas fluorescens, a Gram-negative aerobic bacterium, to investigate biofilm formation in a microfluidic device that mimics porous media. The microfluidic device consists of an array of micro-posts, which were fabricated using soft-lithography. Subsequently, biofilm formation in these devices with flow was investigated and we demonstrate the formation of filamentous biofilms known as streamers in our device. The detailed protocols for fabrication and assembly of microfluidic device are provided here along with the bacterial culture protocols. Detailed procedures for experimentation with the microfluidic device are also presented along with representative results. 相似文献
549.
J-domain containing co-chaperone Mrj (mammalian relative to DnaJ) has been implicated in diverse cellular functions including placental development and inhibition of Huntingtin mediated cytotoxicity. It has also been shown to interact with keratin intermediate filaments. Since keratins undergo extensive reorganization during cell division, its interactor Mrj might also play an important role in the regulation of cell cycle. In support of this hypothesis, we report the up-regulation of Mrj protein in M-phase of HeLa cells implicating its role in mitosis related activities. The protein is dispersed throughout the cell during late mitosis and is localized in nucleolus during interphase, confirming that the activity of Mrj is regulated by its cell cycle specific expression together with its differential subcellular localization. 相似文献
550.