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111.
Existing drugs for visceral leishmaniasis (VL) are partially effective, toxic, having high cost and long term treatment. Their efficacies are also compromised due to suppression of immune function associated during the course of infection. Combination therapy including a potential and safe immunostimulant with lower doses of effective drug has proven as a significant approach which is more effective than immunotherapy or drug therapy alone. In the present study, we have used the combination of Pam3Cys (an in-built immunoadjuvant and TLR2 ligand) and miltefosine. Initially dose optimization of both the agents was carried out and after that, antileishmanial effect of their combination was evaluated. All experiments were done in BALB/c mouse model. The immunomodulatory role of Pam3Cys on the immune functions of the host receiving combination treatment was also determined using immunological and biochemical parameters viz. phagocytosis, Th1/Th2 cytokines and production of ROS, RNS and H(2)O(2). Combination group showed significant enhancement in parasitic inhibition as compared to groups receiving miltefosine and Pam3Cys separately. Enhanced production of Th1 cytokines as well as ROS, RNS and H(2)O(2) was witnessed during the study of immunological alterations. Remarkable increase in phagocytosis index was also observed. Thus, the risk of development of drug resistance against miltefosine can be resolved through using low doses of it and Pam3Cys (single-dose) in combination and also provide a promising alternative for cure of leishmaniasis, with a pronounced transformation of the host immune response.  相似文献   
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The benthic amphipod Diporeia spp. was once the predominant macroinvertebrate in deep, offshore regions of the Laurentian Great Lakes. However, since the early 1990s, Diporeia populations have steadily declined across the area. It has been hypothesized that this decline is due to starvation from increasing competition for food with invasive dreissenid mussels. In order to gain a better understanding of the changes in Diporeia physiology during starvation, we applied two-dimensional gas chromatography coupled with time of flight mass spectrometry (GCXGC/TOF-MS) for investigating the responses in Diporeia metabolome during starvation. We starved Diporeia for 60 days and collected five organisms every 12 days for metabolome analyses. Upon arrival to the laboratory, organisms were flash frozen and served as control (day 0). We observed an increase in lipid oxidation and protein catabolism with subsequent declines of essential amino acids (proline, glutamine, and phenylalanine), down-regulation of glycerophospholipid and sphingolipid metabolism, and decreased polyunsaturated fatty acid abundance in nutritionally stressed Diporeia. Abundance of 1-Iodo-2-methylundecane, a metabolite closely related to insect pheromones, also declined with starvation. This research has further substantiated the applicability of GCXGC/TOF-MS as a research tool in the field of environmental metabolomics. The next step is to apply this new knowledge for evaluating nutritional status of feral Diporeia to elucidate the underlying cause(s) responsible for their decline in the Great Lakes.  相似文献   
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Pretreatment of lignocellulosic biomasses, the first step in their conversion to utilizable molecules requires very high energy (steam and electricity), corrosion resistant high-pressure reactors and high temperatures. These severe conditions not only add to the cost component of the entire process but also lead to the loss of sugars to the side reactions. Microbial pretreatments have been reported to be associated with reducing the cost factors as well as the severities of the reactions. Eight bioagents, including fungi and bacteria, were screened for their pretreatment effects on sugarcane trash. They narrowed down the C:N ratio of trash from 108:1 to a varying range of approximately 42:1 to 60:1.The maximum drop in C:N ratio of 61% was observed using Aspergillus terreus followed by Cellulomonas uda (52%) and Trichoderma reesei and Zymomonas mobilis (49%). The bioagents helped in degradation of sugarcane trash by production of cellulases, the maximum being produced by A. terreus, (12 fold) followed by C. uda (10 fold), Cellulomonas cartae (9 fold) and Bacillus macerans (8 fold). The microbial pretreatment of trash rendered the easy accessibility of sugars for enzymatic hydrolysis, which can be directed for production of alcohol.  相似文献   
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The terminations of the Main Line—C on the plams of 390 schizophrenic male patients were analysed and classified into four modal types according to the direction of their path following Plato's classification (1970). Schizophrenic patients classified into three major sub-categories namely Paranoid (256 palms) Hebephrenic (256 palms), Catatonic (202 palms) and Undifferentiated (66 palms), were taken from the same ethnic group from Yerawada Mental Hospital, Pune and Sassoon General Hospital, Pune (India). Comparisons were made with the respective normal caste control. The frequency of these four model types exhibit strong variations among themselves and between the patients belonging to the sub-categories of schizophrenia. Considerable increase has been observed on the Left Palm of the Paranoid and Catatonic patients for the incidence of Radial and Proximal types. The incidence of Ulnar type showed consistent decrease bilaterally, among all the sub-categories. Absent types showed a steep increase in all the sub-categories of Schizophrenic.  相似文献   
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Macroautophagy/autophagy has emerged as a resistance mechanism to anticancer drug treatments that induce metabolic stress. Certain tumors, including a subset of KRAS-mutant NSCLCs have been shown to be addicted to autophagy, and potentially vulnerable to autophagy inhibition. Currently, autophagy inhibition is being tested in the clinic as a therapeutic component for tumors that utilize this degradation process as a drug resistance mechanism. The current study provides evidence that HSP90 (heat shock protein 90) inhibition diminishes the expression of ATG7, thereby impeding the cellular capability of mounting an effective autophagic response in NSCLC cells. Additionally, an elevation in the expression level of CASP9 (caspase 9) prodomain in KRAS-mutant NSCLC cells surviving HSP90 inhibition appears to serve as a cell survival mechanism. Initial characterization of this survival mechanism suggests that the altered expression of CASP9 is mainly ATG7 independent; it does not involve the apoptotic activity of CASP9; and it localizes to a late endosomal and pre-lysosomal phase of the degradation cascade. HSP90 inhibitors are identified here as a pharmacological approach for targeting autophagy via destabilization of ATG7, while an induced expression of CASP9, but not its apoptotic activity, is identified as a resistance mechanism to the cellular stress brought about by HSP90 inhibition.  相似文献   
119.
Urine albumin excretion rates were measured in overnight timed samples from diabetic and non-diabetic schoolchildren. The excretion rates in the diabetics were significantly higher than those in the controls and were positively correlated with age, duration of diabetes, and glycaemic control. Diabetic children aged 12 years and older had significantly higher albumin excretion rates than younger diabetic children matched for duration of disease. Among the non-diabetic controls there was no correlation between albumin excretion rate and age and the girls excreted significantly more albumin than the boys. Measurement of the overnight albumin excretion rate may provide a useful early indicator of the progression to clinical proteinuria in diabetes and is free from random variations such as that due to exercise.  相似文献   
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The involvement of p53 as a determinant of chemosensitivity or radiosensitivity is not well understood and is complicated by numerous contradictory reports. Here we have addressed this issue using a series of isogenic clones derived from two neuroblastoma cell lines that express wild-type p53 genes, Nub7 and IMR32. Two different mutant p53 transgenes were used in an attempt to disrupt p53 function in the clones. Our findings indicate that the cellular response is dependent on the genotoxic agent used as well as on the specific p53 transgene used. Cellular radiosensitivity showed no association with apoptosis or with the ability of the cells to arrest in G1 after irradiation. An association was observed, however, between gamma-radiation sensitivity and DNA double-strand break rejoining activity.  相似文献   
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