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Virus neutralizing MAb binding and T helper cell stimulating peptide epitopes from structural and non-structural proteins of Japanese encephalitis virus were delineated. It was observed that priming by T helper peptides potentiated neutralizing antibody response against JE virus. Immunization with chimeric T helper - B cell peptides could thus protect mice from lethal challenge with JE virus.  相似文献   
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Journal of Bioenergetics and Biomembranes - Traumatic brain injury (TBI) is still the leading cause of disability in young adults worldwide. The major mechanisms – diffuse axonal injury,...  相似文献   
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Derived from any somatic cell type and possessing unlimited self-renewal and differentiation potential, induced pluripotent stem cells (iPSCs) are poised to revolutionize stem cell biology and regenerative medicine research, bringing unprecedented opportunities for treating debilitating human diseases. To overcome the limitations associated with safety, efficiency, and scalability of traditional iPSC derivation, expansion, and differentiation protocols, biomaterials have recently been considered. Beyond addressing these limitations, the integration of biomaterials with existing iPSC culture platforms could offer additional opportunities to better probe the biology and control the behavior of iPSCs or their progeny in vitro and in vivo. Herein, we discuss the impact of biomaterials on the iPSC field, from derivation to tissue regeneration and modeling. Although still exploratory, we envision the emerging combination of biomaterials and iPSCs will be critical in the successful application of iPSCs and their progeny for research and clinical translation.  相似文献   
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Genetic polymorphisms of pvdhfr and pvdhps genes of Plasmodium vivax were investigated in 83 blood samples collected from patients in the Philippines, Bangladesh, and Nepal. The SNP-haplotypes of the pvdhfr gene at the amino acid positions 13, 33, 57, 58, 61, 117, and 173, and that of the pvdhps gene at the positions 383 and 553 were analyzed by nested PCR-RFLP. Results suggest diverse polymorphic patterns of pvdhfr alone as well as the combination patterns with pvdhps mutant alleles in P. vivax isolates collected from the 3 endemic countries in Asia. All samples carried mutant combination alleles of pvdhfr and pvdhps. The most prevalent combination alleles found in samples from the Philippines and Bangladesh were triple mutant pvdhfr combined with single mutant pvdhps allele and triple mutant pvdhfr combined with double wild-type pvdhps alleles, respectively. Those collected from Nepal were quadruple mutant pvdhfr combined with double wild-type pvdhps alleles. New alternative antifolate drugs which are effective against sulfadoxine-pyrimethamine (SP)-resistant P. vivax are required.  相似文献   
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An economical and efficient one step synthesis of a series of 8-(arylidene)-4-(aryl)-5,6,7,8-tetrahydro-quinazolin-2-ylamines and 9-(arylidene)-4-(aryl)-6,7,8,9-tetrahydro-5H-cycloheptapyrimidin-2-ylamines by the reaction of bis-benzylidene cycloalkanones and guanidine hydrochloride in presence of NaH has been developed. All the synthesized compounds were evaluated against Mycobacterium tuberculosis H37Rv strain and the α-glucosidase and glycogen phosphorylase enzymes. Few of the compounds have shown interesting in vitro activity with MIC up to 3.12 μg/mL against M. tuberculosis and very good inhibition of α-glucosidase and glycogen phosphorylase enzymes. The most potent non toxic compound 40 exhibited about 58% ex vivo activity at MIC of 3.12 μg/mL. The present study opens a new gate to synthesize antitubercular agents for diabetic TB patients. In silico docking studies indicate that mycobacterial dihydrofolate reductase is the possible target of these compounds.  相似文献   
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Acylation of Pseudomonas cepacia lipase with Pyromellitic dianhydride to modify 72% of total amino groups was carried out. Different organic solvents were screened for precipitation of modified lipase. It was found that 1,2-dimethoxyethane was the best precipitant which precipitated 97% protein and complete activity. PCMC (protein coated microcrystals), CLPCMC (crosslinked protein coated microcrystals), EPROS (enzyme precipitated and rinsed with organic solvents) and pH tuned preparations of modified and unmodified lipase were prepared and used for carrying out transesterification reaction with n-octane and dimethyl formamide (DMF) as reaction medium. In n-octane, among all the preparations, CLPCMC of modified lipase gave highest rate (1970 nmol min−1 mg−1) as compared to unmodified pH tuned lipase (128 nmol min−1 mg−1). In DMF, with both 1% (v/v) and 5% (v/v) water content, CLPCMC showed highest initial rate of 0.72 and 7.2 nmol min−1 mg−1, respectively. Unmodified pH tuned lipase showed no activity at all in DMF with both 1% and 5% (v/v) water content.  相似文献   
59.
The expression of cathepsin L, a lysosomal protease, is known to be elevated in cancer and other pathologies. Multiple splice variants of human cathepsin L with variable 5'UTRs exist, which encode for the same protein. Previously we have observed that variant hCATL A (bearing the longest 5'UTR) was translated in vitro with significantly lower efficiency than variant hCATL AIII (bearing the shortest 5'UTR). Contrary to these findings, results of the present study reveal that in cancer cells, hCATL A mRNA exhibits higher translatability in spite of having lower stability than AIII. This is the first report demonstrating a highly contrasting trend in translation efficiencies of hCATL variants in rabbit reticulocytes and live cells. Expression from chimeric mRNAs containing 5'UTRs of A or AIII upstream to luciferase reporter cDNA established the A UTR to be the sole determinant for this effect. Transient transfections of bicistronic plasmids and mRNAs confirmed the presence of a functional Internal Ribosome Entry Site in this UTR. Our data suggest that differential stability and translation initiation modes mediated by the 5'UTRs of human cathepsin L variants are involved in regulating its expression.  相似文献   
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