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51.
P. B. Kavi Kishor S. Anil Kumar Jalaja Naravula P. Hima Kumari Divya Kummari Rajasheker Guddimalli Sujatha Edupuganti Appa Rao Karumanchi Perumal Venkatachalam Prashanth Suravajhala Rathnagiri Polavarapu 《Physiology and Molecular Biology of Plants》2021,27(10):2433
Exploding global population, rapid urbanization, salinization of soils, decreasing arable land availability, groundwater resources, and dynamic climatic conditions pose impending damage to our food security by reducing the grain quality and quantity. This issue is further compounded in arid and semi-arid regions due to the shortage of irrigation water and erratic rainfalls. Millets are gluten (a family of proteins)-free and cultivated all over the globe for human consumption, fuel, feed, and fodder. They provide nutritional security for the under- and malnourished. With the deployment of strategies like foliar spray, traditional/marker-assisted breeding, identification of candidate genes for the translocation of important minerals, and genome-editing technologies, it is now tenable to biofortify important millets. Since the bioavailability of iron and zinc has been proven in human trials, the challenge is to make such grains accessible. This review encompasses nutritional benefits, progress made, challenges being encountered, and prospects of enriching millet crops with essential minerals. 相似文献
52.
Subramanian Vedhanarayanan Karthikeyan Subbu Perumal Krithika Arun Shetty Perumal Yogeeswari Dharmarajan Sriram 《Bioorganic & medicinal chemistry letters》2009,19(11):3006-3009
A series of novel 2-aryl-3,4-dihydro-2H-thieno[3,2-b]indoles has been synthesised regioselectively in good yields from the reaction of 5-aryldihydro-3(2H)-thiophenones and arylhydrazine hydrochloride. This reaction is found to be assisted by microwaves. The thieno[3,2-b]indoles were evaluated for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB) and multi-drug resistant M. tuberculosis (MDR-TB). Among 22 compounds screened, [2-(2,4-dichlorophenyl)-7-fluoro-3,4-dihydro-2H-thieno[3,2-b]indole] (6t) was found to the most active compound with MIC of 0.4 μg/mL against MTB and MDR-TB. 相似文献
53.
Staphylococcus aureus, an opportunistic pathogen, causes diverse community and nosocomial-acquired human infections, including folliculitis, impetigo, sepsis, septic arthritis, endocarditis, osteomyelitis, implant-associated biofilm infections and contagious mastitis in cattle. In recent days, both methicillin-sensitive and methicillin-resistant S. aureus infections have increased. Highly effective anti-staphylococcal agents are urgently required. Lysostaphin is a 27 kDa zinc metallo antimicrobial lytic enzyme that is produced by Staphylococcus simulans biovar staphylolyticus and was first discovered in the 1960s. Lysostaphin is highly active against S. aureus strains irrespective of their drug-resistant patterns with a minimum inhibitory concentration of ranges between 0·001 and 0·064 μg ml−1. Lysostaphin has activity against both dividing and non-dividing S. aureus cells; and can seep through the extracellular matrix to kill the biofilm embedded S. aureus. In spite of having excellent anti-staphylococcal activity, its clinical application is hindered because of its immunogenicity and reduced bio-availability. Extensive research with lysostaphin lead to the development of several engineered lysostaphin derivatives with reduced immunogenicity and increased serum half-life. Therapeutic efficacy of both native and engineered lysostaphin derivatives was studied by several research groups. This review provides an overview of the therapeutic applications of native and engineered lysostaphin derivatives developed to eradicate S. aureus infections. 相似文献
54.
Sambasivam D Liu CW Jayaraman M Malar EJ Rajadas J 《Biochimica et biophysica acta》2008,1784(11):1659-1667
Most of the disease causing proteins such as beta amyloid, amylin, and huntingtin protein, which are natively disordered, readily form fibrils consisting of beta-sheet polymers. Though all amyloid fibrils are made up of beta-sheet polymers, not all peptides with predominant beta-sheet content in the native state develop into amyloid fibrils. We hypothesize that stable amyloid like fibril formation may require mixture of different conformational states in the peptide. We have tested this hypothesis on amyloid forming peptide namely HCl(Ile)(5)NH(CH(2)CH(2)O)(3)CH(3) (I). We show peptide I, has propensity to form self-assembled structures of beta-sheets in aqueous solutions. When incubated over a period of time in aqueous buffer, I self assembled into beta sheet like structures with diameters ranging from 30 to 60 A that bind with amyloidophilic dyes like Congo red and Thioflavin T. Interestingly peptide I developed into unstable fibrils after prolonged aging at higher concentration in contrast with the general mature fibril-forming propensity of various amyloid petides known to date. 相似文献
55.
Perumal Venkatachalam Natesan Geetha Narayanasamypillai Jayabalan 《Journal of Plant Biology》1998,41(1):1-8
This study was designed to evaluate the effect of phytohormones on plant regeneration from epicotyl and hypocotyl explants
of two groundnut (Arachis hypogaea) cultivars. Explants cultured on media with auxins and in combination with cytokinin produced high frequency of callus. After
four weeks, callus from these cultures was transferred to medium with cytokinin and reduced auxin, shoot buds regenerated
from the cultures. A high rate of shoot bud regeneration was observed on medium supplemented with 2.0 mg/L BAP and 0.5 mg/L
NAA. Among the different auxins tested, NAA was found to be most effective, producing the highest frequency of shoot buds
per responding cultures. Of the two explants tested, epicotyl was found to be best for high frequency shoot bud regeneration.
Multiple shoots arose on MS medium supplemented with BAP or kinetin (1.0–5.0 mg/L) plus IBA (1.0 mg/L), with maximum production
occurring at 5.0 mg/L. The elongated shoots developed rootsin vitro upon transfer to MS medium supplemented with NAA or IBA (0.5–2.0 mg/L) and kinetin (0.5 mg/L) for 15 days.In vitro produced plantlets, were transferred to soil and placed in a glasshouse developed successfully, matured, and set seeds. 相似文献
56.
Peramaiyan Rajendran Thamaraiselvan Rengarajan Jayakumar Thangavel Yutaka Nishigaki Dhanapal Sakthisekaran Gautam Sethi Ikuo Nishigaki 《International journal of biological sciences》2013,9(10):1057-1069
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
57.
Chemoprevention is one of the most promising and realistic approaches in the prevention of cancer. Several bioactive compounds present in fruits and vegetables have revealed their cancer curative potential on hepatocellular carcinoma. Naringenin is one such naturally occurring flavonoid widely found in citrus fruits. In this study, we examined the molecular mechanisms by which naringenin inhibited NDEA‐induced hepatocellular carcinoma in rats by analysing the expression patterns of proliferating cell nuclear antigen, Bcl‐2, NF‐κB, VEGF and MMP‐2/9. Enhanced cell proliferation and apoptotic evasion in NDEA‐induced hepatocarcinogenesis was associated with imbalance in pro‐apoptotic and anti‐apoptotic proteins together with upregulation of proliferating cell nuclear antigen (PCNA) and downregulation of caspase‐3. Administration of pretreatment and posttreatment of naringenin decreased the expression of PCNA and Bcl‐2 and increased the expression of Bax and caspase‐3, indicating antiproliferative and apoptotic effects, respectively. Administration of NDEA increased the tumour expression of NF‐κB, COX‐2, VEGF, MMP‐2 and MMP‐9 that was correlated with more aggressive lesions and tumour growth. Downregulation of NF‐κB, VEGF and MMPs by naringenin seen in the present study were correlated with the inhibition of liver tumour induced by NDEA. Our results suggest that naringenin could act as a legitimate agent by inhibiting cancer processes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
58.
Ayyasami Ramanathan Perumal Vidhyasekaran Luke Rathinakumar 《Archives Of Phytopathology And Plant Protection》2013,46(2):105-114
Several regenerants through organogenesis were obtained in greengram ( Vigna radiata L. wilczek). Cytokinins appear to be important in inducing organogenesis and IAA induces root induction. Heritable variations could be seen among organogenesis regenerants. Some of the regenerants showed resistance to powdery mildew while some others showed resistance to yellow mosaic virus disease. The disease resistant characters were stable also in R 3 and R 4 generations. 相似文献
59.
The polyamines stimulated tyrosine hydroxylase in whole homogenates of bovine caudate nuclei approximately 2 fold. TheV
max forl-tyrosine increased by 2.3 fold while theK
m
s forl-tyrosine and for the cofactor (DMPH4) were unchanged.l-Aromatic amino acid decarboxylase from whole rat brain homogenate was stimulated by about 40% in the presence of polyamines. These findings suggest that increased polyamine levels associated with increased cellular synthetic activity can modify the synthesis of neurotransmitters. 相似文献
60.
Subramanian P Dakshayani KB Pandi-Perumal SR Trakht I Cardinali DP 《Redox report : communications in free radical research》2008,13(2):78-86
To compare the effects of alpha-ketoglutarate (alpha-KG) and melatonin on 24-h rhythmicity of oxidative stress in N-nitrosodiethylamine (NDEA)-injected Wistar male rats, melatonin (5 mg/kg i.p.) or alpha-KG (2 g/kg through an intragastric tube) was given daily for 20 weeks. In blood collected at 6 time points during a 24-h period, serum activity of aspartate transaminase (AST) and alanine transaminase (ALT) and the levels of alpha-fetoprotein (alpha-FP) were measured as markers of liver function. To assess lipid peroxidation and the antioxidant status, plasma levels of thiobarbituric acid reactive substances (TBARS) and of reduced glutathione (GSH) were measured, together with the activity of erythrocyte superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST). NDEA augmented mesor and amplitude of rhythms in AST and ALT activity and plasma alpha-FP levels and mesor values of plasma TBARS, while decreasing mesor values of plasma GSH and erythrocyte SOD, CAT, GPx and GST. Acrophases were delayed by NDEA in all cases except for alpha-FP rhythm, which became phase-advanced. Co-administration of melatonin or alpha-KG partially counteracted the effects of NDEA. Melatonin decreased mesor of plasma TBARS and augmented mesor of SOD activity. The results indicate that melatonin and alpha-KG are effective in protecting from NDEA-induced perturbation of 24-h rhythms in oxidative stress. Melatonin augmented antioxidant defense in rats. 相似文献