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11.
Twenty-six rice landraces from West Bengal, India were evaluated for antixenosis and tolerance against brown planthopper (BPH) biotype 4 at the Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal. High levels of resistance were observed in six landraces, namely Badshabhog, Gamra, Haldichuri, Janglijata, Kalabhat and Khara. These phenotypically resistant rice landraces including Ptb33 exhibited lowest feeding rate, fecundity, nymphal and adult preference, survival, plant dry weight loss per mg of BPH dry weight produced (PDWL), and higher functional plant loss index (FPLI), more days to wilt and unhatched eggs compared with the susceptible check Swarna. All the landraces were classified into four major clusters at 10 unit distance by the scale of similarity during genetic diversity analysis through 21 gene-linked SSR markers of BPH resistance. Some phenotypically resistant landraces were gathered under the major cluster I indicating their analogous genetic history, while some were grouped with susceptible landraces exhibiting their genetic variation. The resistant landraces can be used as potential donors in the breeding programme for the development of rice varieties with resistance to BPH.  相似文献   
12.
ABSTRACT

A laboratory-scale biofilter unit packed with a mixture of compost, sugarcane bagasse, and granulated activated carbon (GAC) in the ratio of 55:30:15 by weight was used for a biofiltration study of air stream containing benzene, toluene, ethylbenzene, and o-xylene (BTEX). The effect of superficial velocity on mass transfer coefficient for the packing was studied by maintaining gas flow rates of 3, 4, 5, 6, and 8 L min?1 for inlet concentrations of 0.1, 0.4, and 0.8 g m?3 for each of benzene, toluene, ethylbenzene, and o-xylene. The maximum elimination capacity was found to be 20.92, 22.72, 20.73, and 18.94 g m?3 h?1 for BTEX, respectively, for stated flow rates. Removal efficiency of BTEX decreased from 99% to 71% for increasing inlet concentration from 0.1 to 0.8 g m?3. Gas film mass transfer coefficient predicted by modified Onda's equation was within ±10% of the experimental values.  相似文献   
13.
Cetirizine is a piperazine-derived second-generation antihistaminic drug recommended for treatment of pruritus associated with atopic dermatitis. The present investigation encompasses development of a nanosized novel elastic vesicle-based topical formulation of cetirizine dihydrochloride using combination of Phospholipon® 90G and edge activators with an aim to have targeted peripheral H1 antihistaminic activity. The formulation was optimized with respect to phospholipid/drug/charge inducer ratio along with type and concentration of edge activator. The optimized formulation was found to be satisfactory with respect to stability, drug content, entrapment efficiency, pH, viscosity, vesicular size, spreadability, and morphological characteristics. The ex vivo permeation studies through mice skin were performed using Franz diffusion cell assembly. It was found that the mean cumulative percentage amount permeated in 8 h was almost twice (60.001 ± 0.332) as compared to conventional cream (33.268 ± 0.795) and aqueous solution of drug (32.616 ± 0.969), suggesting better penetration and permeation of cetirizine from the novel vesicular delivery system. Further, therapeutic efficacy of optimized formulation was assessed against oxazolone-induced atopic dermatitis in mice. It was observed that the developed formulation was highly efficacious in reducing the itching score (4.75 itches per 20 min) compared to conventional cream (9.75 itches per 20 min) with profound reduction in dermal eosinophil count and erythema score. To conclude, a novel vesicular, dermally safe, and nontoxic topical formulation of cetirizine was successfully developed and may be used to treat atopic dermatitis after clinical investigation.KEY WORDS: atopic dermatitis, cetirizine, elastic vesicles, oxazolone, topical  相似文献   
14.
Alterations of endothelial cells and the vasculature play a central role in the pathogenesis of a broad spectrum of the most dreadful of human diseases, as endothelial cells have the key function of participating in the maintenance of patent and functional capillaries. The endothelium is directly involved in peripheral vascular disease, stroke, heart disease, diabetes, insulin resistance, chronic kidney failure, tumor growth, metastasis, venous thrombosis, and severe viral infectious diseases. Dysfunction of the vascular endothelium is thus a hallmark of human diseases. In this review the main endothelial abnormalities found in various human diseases such as cancer, diabetes mellitus, atherosclerosis, and viral infections are addressed.  相似文献   
15.
16.
Accumulating evidence(s) indicate that CXCL12-CXCR4 signaling cascade plays an important role in the process of invasion and metastasis that accounts for more than 80% of deaths in hepatocellular carcinoma (HCC) patients. Thus, identification of novel agents that can downregulate CXCR4 expression and its associated functions have a great potential in the treatment of metastatic HCC. In the present report, we investigated an anthraquinone derivative, emodin for its ability to affect CXCR4 expression as well as function in HCC cells. We observed that emodin downregulated the expression of CXCR4 in a dose-and time-dependent manner in HCC cells. Treatment with pharmacological proteasome and lysosomal inhibitors did not have substantial effect on emodin-induced decrease in CXCR4 expression. When investigated for the molecular mechanism(s), it was observed that the suppression of CXCR4 expression was due to downregulation of mRNA expression, inhibition of NF-κB activation, and abrogation of chromatin immunoprecipitation activity. Inhibition of CXCR4 expression by emodin further correlated with the suppression of CXCL12-induced migration and invasion in HCC cell lines. In addition, emodin treatment significantly suppressed metastasis to the lungs in an orthotopic HCC mice model and CXCR4 expression in tumor tissues. Overall, our results show that emodin exerts its anti-metastatic effect through the downregulation of CXCR4 expression and thus has the potential for the treatment of HCC.  相似文献   
17.
Analysis of any mammalian plasma proteome is a challenge, particularly by mass spectrometry, due to the presence of albumin and other abundant proteins which can mask the detection of low abundant proteins. As detection of human plasma proteins is valuable in diagnostics, exploring various workflows with minimal fractionation prior to mass spectral analysis, is required in order to study population diversity involving analysis in a large cohort of samples. Here, we used ‘reference plasma sample’, a pool of plasma from 10 healthy individuals from Indian population in the age group of 25–60 yrs including 5 males and 5 females. The 14 abundant proteins were immunodepleted from plasma and then evaluated by three different workflows for proteome analysis using a nanoflow reverse phase liquid chromatography system coupled to a LTQ Orbitrap Velos mass spectrometer. The analysis of reference plasma sample a) without prefractionation, b) after prefractionation at peptide level by strong cation exchange chromatography and c) after prefractionation at protein level by sodium dodecyl sulfate polyacrylamide gel electrophoresis, led to the identification of 194, 251 and 342 proteins respectively. Together, a comprehensive dataset of 517 unique proteins was achieved from all the three workflows, including 271 proteins with high confidence identified by≥2 unique peptides in any of the workflows or identified by single peptide in any of the two workflows. A total of 70 proteins were common in all the three workflows. Some of the proteins were unique to our study and could be specific to Indian population. The high-confidence dataset obtained from our study may be useful for studying the population diversity, in discovery and validation process for biomarker identification.  相似文献   
18.
Parkinson disease (PD) is a chronic neurodegenerative disease characterized by a slow and progressive degeneration of dopaminergic neurons in substantia nigra. The pathophysiological mechanisms underlying PD remain unclear. Pin1, a major peptidyl-prolyl isomerase, has recently been associated with certain diseases. Notably, Ryo et al. (Ryo, A., Togo, T., Nakai, T., Hirai, A., Nishi, M., Yamaguchi, A., Suzuki, K., Hirayasu, Y., Kobayashi, H., Perrem, K., Liou, Y. C., and Aoki, I. (2006) J. Biol. Chem. 281, 4117–4125) implicated Pin1 in PD pathology. Therefore, we sought to systematically characterize the role of Pin1 in PD using cell culture and animal models. To our surprise we observed a dramatic up-regulation of Pin1 mRNA and protein levels in dopaminergic MN9D neuronal cells treated with the parkinsonian toxicant 1-methyl-4-phenylpyridinium (MPP+) as well as in the substantia nigra of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Notably, a marked expression of Pin1 was also observed in the substantia nigra of human PD brains along with a high co-localization of Pin1 within dopaminergic neurons. In functional studies, siRNA-mediated knockdown of Pin1 almost completely prevented MPP+-induced caspase-3 activation and DNA fragmentation, indicating that Pin1 plays a proapoptotic role. Interestingly, multiple pharmacological Pin1 inhibitors, including juglone, attenuated MPP+-induced Pin1 up-regulation, α-synuclein aggregation, caspase-3 activation, and cell death. Furthermore, juglone treatment in the MPTP mouse model of PD suppressed Pin1 levels and improved locomotor deficits, dopamine depletion, and nigral dopaminergic neuronal loss. Collectively, our findings demonstrate for the first time that Pin1 is up-regulated in PD and has a pathophysiological role in the nigrostriatal dopaminergic system and suggest that modulation of Pin1 levels may be a useful translational therapeutic strategy in PD.  相似文献   
19.
Immunotoxins are rationally designed cancer targeting and killing agents. Disulfide stabilized antibody Fv portion—toxin conjugates (dsFv-toxin) are third generation immunotoxins containing only the antibody fragment variable portions and a toxin fused to the VH or VL. Pseudomonas exotoxin fragment (PE-38) is a commonly used toxin in immunotoxin clinical trials. dsFv-toxin purification was previously published, but the recovery was not satisfactory. This report describes the development of a cGMP production process of the dsFv-toxin that incorporated a novel purification method. The method has been successfully applied to the clinical manufacturing of two dsFv-PE38 immunotoxins, MR1-1 targeting EGFRvIII and HA22 targeting CD22. The two subunits, VL and VH PE-38 were expressed separately in Escherichia coli using recombinant technology. Following cell lysis, inclusion bodies were isolated from the biomass harvested from fermentation in animal source component-free media. The dsFv-toxin was formed after denaturation and refolding, and subsequently purified to homogeneity through ammonium sulfate precipitation, hydrophobic interaction and ion-exchange chromatography steps. It was shown, in a direct comparison experiment using MR1-1 as model protein, that the recovery from the new purification method was improved three times over that from previously published method. The improved recovery was also demonstrated during the clinical production of two dsFv-PE38 immunotoxins—MR1-1 and HA22.  相似文献   
20.
Two series of new benzoxazepines substituted with different alkyl amino ethyl chains were synthesized comprising synthetic steps of inter and intramolecular Mitsunobu reaction, lithium aluminium hydride (LAH) reduction, debenzylation, bimolecular nucleophilic substitution (SN2) reaction. The present study investigates the effect of a tyrosine-based benzoxazepine derivative in human breast cancer cells MCF-7 and MDA-MB-231 and in breast cancer animal model. The anti-proliferative effect of 15a on MCF-7 cells was associated with G1 cell-cycle arrest. This G1 growth arrest was followed by apoptosis as 15a dose dependently increased phosphatidylserine exposure, PARP cleavage and DNA fragmentation that are hallmarks of apoptotic cell death. Interestingly, 15a activated components of both intrinsic and extrinsic pathways of apoptosis characterized by activation of caspase-8 and -9, mitochondrial membrane depolarization and increase in Bax/Bcl2 ratio. However, use of selective caspase inhibitors revealed that the caspase-8-dependent pathway is the major contributor to 15a-induced apoptosis. Compound 15a also significantly reduced the growth of MCF-7 xenograft tumors in athymic nude mice. Together, 15a could serve as a base for the development of a new group of effective breast cancer therapeutics.  相似文献   
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