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31.
The present investigation was carried out to characterize genotypic variability in chickpea for water deficit tolerance by exploring the antioxidative defense system and seedling growth. Twenty nine chickpea genotypes including cultivars and advanced lines were grown under control and water deficit conditions induced by adding 3 % mannitol. The genotypes showed differential response in seedling growth under water deficit conditions. The activities of catalase (CAT) and superoxide dismutase (SOD) were observed to be differentially expressed in the roots of various genotypes, under control and water deficit conditions. The contents of H2O2, malondialdehyde (MDA) and proline were also observed to be variable in the roots of all the genotypes, under control and water deficit conditions. Stress tolerance index for the various parameters, viz, CAT and SOD activity, H2O2, MDA and proline content, root length, shoot length and their biomass was determined and the level of stress resistance calculated. The genotypes which showed increased activities of CAT and SOD, decreased contents of H2O2 and MDA together with least affected seedling growth under water deficit conditions exhibited higher stress resistance capacity. Multivariate principal component analysis for all the parameters affected under water deficit conditions, grouped the genotypes into three clusters having different (high, moderate and low) levels of stress resistance. Complete linkage clustering grouped these genotypes into two major clusters-I and II. The genotypes present in sub–sub cluster ‘A1’ and sub cluster ‘B’ of major cluster-I have been observed to possess high stress resistance levels for respective parameters. It can thus be concluded that chickpea genotypes exhibiting increased stress resistance levels in relation to SOD and CAT activities, H2O2 and MDA contents and seedling growth would have higher stress tolerance under water deficit conditions.  相似文献   
32.
The peritrophic matrix (PM) plays a key role in compartmentalization of the blood meal and as barrier to pathogens in many disease vectors. To establish an infection in sand flies, Leishmania must escape from the endoperitrophic space to prevent excretion with remnants of the blood meal digestion. In spite of the role played regarding Leishmania survival, little is known about sand fly PM molecular components and structural organization. We characterized three peritrophins (PpPer1, PpPer2, and PpPer3) from Phlebotomus papatasi. PpPer1 and PpPer2 display, respectively, four and one chitin-binding domains (CBDs). PpPer3 on the other hand has two CBDs, one mucin-like domain, and a putative domain with hallmarks of a CBD, but with changes in key amino acids. Temporal and spatial expression analyses show that PpPer1 is expressed specifically in the female midgut after blood feeding. PpPer2 and PpPer3 mRNAs were constitutively expressed in midgut and hindgut, with PpPer3 also being expressed in Malpighian tubules. PpPer2 was the only gene expressed in developmental stages. Interestingly, PpPer1 and PpPer3 expression are regulated by Le. major infection. Recombinant PpPer1, PpPer2 and PpPer3 were obtained and shown to display similar biochemical profiles as the native; we also show that PpPer1 and PpPer2 are able to bind chitin. Knockdown of PpPer1 led to a 44% reduction in protein, which in spite of producing an effect on the percentage of infected sand flies, resulted in a 39% increase of parasite load at 48 h. Our data suggest that PpPer1 is a component for the P. papatasi PM and likely involved in the PM role as barrier against Le. major infection.  相似文献   
33.
Substituted-3-formylchromones (4ae) on reaction with 1,3-bis-dimethylaminomethylene-thiourea (5) in refluxing toluene solution give novel substituted 5-(o-hydroxyaroyl)pyrimidines (6ae) in high yields. A mechanistic rationalization of the formation of products (6ae) is proffered. Antimicrobial activities of all the synthesized compounds (6ae) were evaluated against various fungal and bacterial strains. Compound 6d display significant antifungal activity (MIC 15) against Geotrichum candidum in comparison fluconazole used as positive control. Some of the compounds also display good antibacterial activity. Cytotoxic profile of compound 6d against HeLa cells indicates that at concentration (20 μM) no significant cell death (~2%) was observed.  相似文献   
34.

Background  

Burkholderia sp. strain SJ98 is known for its chemotaxis towards nitroaromatic compounds (NACs) that are either utilized as sole sources of carbon and energy or co-metabolized in the presence of alternative carbon sources. Here we test for the chemotaxis of this strain towards six chloro-nitroaromatic compounds (CNACs), namely 2-chloro-4-nitrophenol (2C4NP), 2-chloro-3-nitrophenol (2C3NP), 4-chloro-2-nitrophenol (4C2NP), 2-chloro-4-nitrobenzoate (2C4NB), 4-chloro-2-nitrobenzoate (4C2NB) and 5-chloro-2-nitrobenzoate (5C2NB), and examine its relationship to the degradation of such compounds.  相似文献   
35.
There is significant potential for the use of adult mesenchymal stem cells in regenerating musckuloskeletal tissues. The sources of these stem cells discussed in this review are bone marrow, blood, adipose tissue, synovium, periosteum & cartilage. Adult mesenchymal stem cells of bone marrow origin are the cells which are heavily investigated in many studies and have been shown capable of producing a variety of connective tissues especially cartilage and bone. It has recently been suggested that bone marrow derived mesenchymal stem cells originate from microvascular pericytes, and, indeed, many of the tissues from which stem cells have been isolated have good vascularisation and they may give a varied source of cells for future treatments. Clinical trials have shown that these cells are able to be successfully used to regenerate tissues with good clinical outcome. Other sources are showing promise, however, is yet to be brought to the clinical level in humans.  相似文献   
36.
Bioenhancers can increase the bioavailability of metabolism susceptible drugs. The present study was designed to understand the impact of bioenhancer on permeability and bioavailability of a biopharmaceutical drug disposition classification system (BDDCS) class II drug raloxifene (RLX). RLX undergoes extensive first pass metabolism by UGT enzymes in gastrointestinal tract (GIT) and has an oral bioavailability of about 2%. Self-emulsifying drug delivery system (SEDDS) of RLX was developed using a designed approach and this formulation was loaded with reported bioenhancers: quercetin and piperine. These formulations were tested for improvement in permeability and bioavailability of the RLX. The apparent permeability using everted gut sac (P app) for SEDDS (5.26?±?1.10?×?10?8 cm/s) was found to be similar to that of SEDDS with bioenhancers (5.11?±?1.05?×?10?8 cm/s). In oral bioavailability study in rat, SEDDS demonstrated a 4-fold and 2.5-fold higher AUC0–∞ than RLX suspension (control) and marketed product, respectively. No additional improvement in permeability and bioavailability was offered by inclusion of piperine and quercetin (bioenhancers) in the SEDDS.  相似文献   
37.
Next‐generation sequencing (NGS) provides a powerful tool for the discovery of important genes and alleles in crop plants and their wild relatives. Despite great advances in NGS technologies, whole‐genome shotgun sequencing is cost‐prohibitive for species with complex genomes. An attractive option is to reduce genome complexity to a single chromosome prior to sequencing. This work describes a strategy for studying the genomes of distant wild relatives of wheat by isolating single chromosomes from addition or substitution lines, followed by chromosome sorting using flow cytometry and sequencing of chromosomal DNA by NGS technology. We flow‐sorted chromosome 5Mg from a wheat/Aegilops geniculata disomic substitution line [DS5Mg (5D)] and sequenced it using an Illumina HiSeq 2000 system at approximately 50 × coverage. Paired‐end sequences were assembled and used for structural and functional annotation. A total of 4236 genes were annotated on 5Mg, in close agreement with the predicted number of genes on wheat chromosome 5D (4286). Single‐gene FISH indicated no major chromosomal rearrangements between chromosomes 5Mg and 5D. Comparing chromosome 5Mg with model grass genomes identified synteny blocks in Brachypodium distachyon, rice (Oryza sativa), sorghum (Sorghum bicolor) and barley (Hordeum vulgare). Chromosome 5Mg‐specific SNPs and cytogenetic probe‐based resources were developed and validated. Deletion bin‐mapped and ordered 5Mg SNP markers will be useful to track 5M‐specific introgressions and translocations. This study provides a detailed sequence‐based analysis of the composition of a chromosome from a distant wild relative of bread wheat, and opens up opportunities to develop genomic resources for wild germplasm to facilitate crop improvement.  相似文献   
38.
Journal of Plant Research - The present study was conducted to understand the key ecological and biological questions of conservation importance in Drepanostachyum falcatum which aimed to map...  相似文献   
39.
Modification of low density lipoprotein by nonenzymic glycosylation resulted in decreased receptor-mediated lipoprotein catabolism. Guggulsterone treatment caused significant increase in binding of [125I] low density lipoprotein as well as [125I] glycosylated low density lipoprotein. Scatchard plot analysis of the binding activity revealed that under the influence of guggulsterone, the liver membrane contains increased amounts of a functional lipoprotein receptor that binds more low density lipoprotein particles.  相似文献   
40.
BACKGROUND: Tumor metastasis and relapse are major obstacles in combating human malignant diseases. Neither radiotherapy alone nor injection of dendritic cells (DCs) can successfully overcome this problem. Radiation induces tumor cell apoptosis and necrosis, resulting in the release of tumor antigen and danger signals, which are favorable for DC capturing antigens and maturation. Hence, the strategy of combined irradiation and DC vaccine may be a novel approach for treating human malignancies and early metastasis. METHODS: To develop an effective combined therapeutic approach, we established a novel concomitant local tumor and liver metastases model through subcutaneous (s.c.) and intravenous (i.v.) injection. We selected the optimal time for DC injection after irradiation and investigated the antitumor effect of combining irradiation with DC intratumoral injection and the related mechanism. RESULTS: Combined treatment with radiotherapy and DC vaccine could induce a potent antitumor immune response, resulting in a significant decrease in the rate of local tumor relapse and the numbers of liver metastases. The related mechanisms for this strong antitumor immunity of this combined therapy might be associated with the production of apoptotic and necrotic tumor antigens and heat shock proteins after irradiation, phagocytosis, migration and maturation of DCs, and induction of more efficient tumor-specific cytotoxic T lymphocyte activity through a cross-presentation pathway. CONCLUSIONS: Co-administration of local irradiation and intratumoral DC injection may be a promising strategy for treating radiosensitive tumors and eliminating metastasis in the clinic.  相似文献   
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