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1.
P Sreenivasula Reddy A Bhagyalakshmi R Ramamurthi 《Archives internationales de physiologie et de biochimie》1986,94(3):193-195
The concentration of haemolymph sugar and the hyperglycaemic activity of eyestalk extract was measured six times (8, 12, 16, 20 and 4 h) over a 24-h period. The concentration of haemolymph sugar and hyperglycaemic activity of eyestalk extract was higher during the night (0 h through 8 h) than that noted in day time (12 h). The variations are closely related to the activity of the animal. 相似文献
2.
Pavithra A. Honnaiah Shankarappa Sridhara Pradeep Gopakkali Nandini Ramesh Eman A. Mahmoud Shaimaa A.M. Abdelmohsen Fatema H. Alkallas Diaa O. El-Ansary Hosam O. Elansary 《Saudi Journal of Biological Sciences》2021,28(6):3453-3460
Crop growth largely depends on radiation. Radiation is the main impetus for photosynthesis and movement of photosynthates from source to sink. Therefore, identification of the optimum sowing windows and suitable cultivars for efficient utilization of radiation is of prime importance. A field study was conducted in red clay soil during 2014 and 2015 Kharif season and the treatments consisted of three genotypes and three sowing windows by using randomized complete block design with three replications. The effect of genotypes and sowing windows was found significant with respect to number of trifoliate leaves, leaf area ratio, dry matter production, grain numbers, pod length, test weight, grain yield, and stover yield of guar during 2014 as compared to 2015 sown crop. Statistically significant plant height, number of trifoliate leaves, number of branches, leaf area ratio, absolute growth rate, leaf area index, dry matter, grain number, pod length, grain yield, stover yield and a higher cumulative radiation interception were recorded with 15th August sown crop as compared to other sowing windows. The plant height, number of trifoliate leaves, number of branches, leaf area ratio, absolute growth rate, leaf area index, dry matter, grain number, pod length, grain yield, stover yield and maximum cumulative interception of radiation were significant with RGC-1003 as compared to RGC-936 and HG-365. It is observed that the incident PAR to dry matter accumulation conversion efficiency was varied with cultivars and different sowing windows which ranges from 0.74 g MJ−1 to 0.79 g MJ−1. 相似文献
3.
Consistent viral evolutionary changes associated with the progression of human immunodeficiency virus type 1 infection
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Shankarappa R Margolick JB Gange SJ Rodrigo AG Upchurch D Farzadegan H Gupta P Rinaldo CR Learn GH He X Huang XL Mullins JI 《Journal of virology》1999,73(12):10489-10502
To understand the high variability of the asymptomatic interval between primary human immunodeficiency virus type 1 (HIV-1) infection and the development of AIDS, we studied the evolution of the C2-V5 region of the HIV-1 env gene and of T-cell subsets in nine men with a moderate or slow rate of disease progression. They were monitored from the time of seroconversion for a period of 6 to 12 years until the development of advanced disease in seven men. Based on the analysis of viral divergence from the founder strain, viral population diversity within sequential time points, and the outgrowth of viruses capable of utilizing the CXCR4 receptor (X4 viruses), the existence of three distinct phases within the asymptomatic interval is suggested: an early phase of variable duration during which linear increases ( approximately 1% per year) in both divergence and diversity were observed; an intermediate phase lasting an average of 1.8 years, characterized by a continued increase in divergence but with stabilization or decline in diversity; and a late phase characterized by a slowdown or stabilization of divergence and continued stability or decline in diversity. X4 variants emerged around the time of the early- to intermediate-phase transition and then achieved peak representation and began a decline around the transition between the intermediate and late phases. The late-phase transition was also associated with failure of T-cell homeostasis (defined by a downward inflection in CD3(+) T cells) and decline of CD4(+) T cells to =200 cells/microliter. The strength of these temporal associations between viral divergence and diversity, viral coreceptor specificity, and T-cell homeostasis and subset composition supports the concept that the phases described represent a consistent pattern of viral evolution during the course of HIV-1 infection in moderate progressors. Recognition of this pattern may help explain previous conflicting data on the relationship between viral evolution and disease progression and may provide a useful framework for evaluating immune damage and recovery in untreated and treated HIV-1 infections. 相似文献
4.
Enhanced detection of human immunodeficiency virus type 1-specific T-cell responses to highly variable regions by using peptides based on autologous virus sequences
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Altfeld M Addo MM Shankarappa R Lee PK Allen TM Yu XG Rathod A Harlow J O'Sullivan K Johnston MN Goulder PJ Mullins JI Rosenberg ES Brander C Korber B Walker BD 《Journal of virology》2003,77(13):7330-7340
The antigenic diversity of human immunodeficiency virus type 1 (HIV-1) represents a significant challenge for vaccine design as well as the comprehensive assessment of HIV-1-specific immune responses in infected persons. In this study we assessed the impact of antigen variability on the characterization of HIV-1-specific T-cell responses by using an HIV-1 database to determine the sequence variability at each position in all expressed HIV-1 proteins and a comprehensive data set of CD8 T-cell responses to a reference strain of HIV-1 in infected persons. Gamma interferon Elispot analysis of HIV-1 clade B-specific T-cell responses to 504 overlapping peptides spanning the entire expressed HIV-1 genome derived from 57 infected subjects demonstrated that the average amino acid variability within a peptide (entropy) was inversely correlated to the measured frequency at which the peptide was recognized (P = 6 x 10(-7)). Subsequent studies in six persons to assess T-cell responses against p24 Gag, Tat, and Vpr peptides based on autologous virus sequences demonstrated that 29% (12 of 42) of targeted peptides were only detected with peptides representing the autologous virus strain compared to the HIV-1 clade B consensus sequence. The use of autologous peptides also allowed the detection of significantly stronger HIV-1-specific T-cell responses in the more variable regulatory and accessory HIV-1 proteins Tat and Vpr (P = 0.007). Taken together, these data indicate that accurate assessment of T-cell responses directed against the more variable regulatory and accessory HIV-1 proteins requires reagents based on autologous virus sequences. They also demonstrate that CD8 T-cell responses to the variable HIV-1 proteins are more common than previously reported. 相似文献
5.
Lakshmanan Venkatachalam R. V. Sreedhar Neelwarne Bhagyalakshmi 《Plant Growth Regulation》2007,51(3):193-205
Use of high levels of growth regulators during micropropagation results in undesirable clonal variability in important commercial
crops such as banana. The present study investigated the effects of high levels of cytokinins on micropropagation in banana
(genotype AAB), and the genetic stability of plantlets was assessed using RAPD and ISSR markers. Cytokinins, such as BA and
kinetin were added to the routine shoot multiplication medium at concentrations up to 10 mg l−1. After 12 weeks of culture involving three subcultures, the maximum number of shoot buds were produced in cultures receiving
either 5 mg l−1 BA (80 shoot buds) or 4 mg l−1 kinetin (62 shoot buds). Certain morphological abnormalities observed during proliferation of shoot buds in vitro were not
observed during acclimatization ex vitro. To check the genetic stability, RAPD and ISSR profiles of micropropagated plantlets
obtained from different cytokinin-treatments were compared with control microplants maintained on MS medium as well as the
field-grown mother plant. A total of 50 RAPD and 12 ISSR primers resulted in 625 distinct and reproducible bands. Thus a total
of 17,400 bands were generated showing homogeneous RAPD and ISSR patterns. Band intensity histogram of each gel confirmed
their monomorphic nature with no genetic variation in all the plantlets analysed. Based on these results a protocol for high
rate shoot multiplication was worked out leading to uniform shoot production. 相似文献
6.
L. Venkatachalam R. Thimmaraju R. V. Sreedhar N. Bhagyalakshmi 《In vitro cellular & developmental biology. Plant》2006,42(3):262-269
Summary Direct shoot and cormlet regeneration from leaf explants were obtained in triploid dessert banana cultivar Nanjanagud Rasabale
(NR) that is classified under the group ‘Silk’ and has the genotype AAB. The response for both cormlet and direct shool formation
was observed only in leaf explants obtained from shoots cultured in liquid medium but not in similar explants obtained from
shoots grown on gelled medium. Shoot initiation occurred after a sequential culture of leaf (sheath) explants on modified
Murashige and Skoog (MS) medium supplemented with different growth regulators. In the sequence, the leaf explants were cultured
first on medium with a high level (22.4 μM) of benzyladenine (BA), second on indolc-3-butyric acid (IBA) supplemented medium, and third on reduced BA medium under incubation
in the dark. The highest adventitious shoot regeneration in 24% of the explants, with the number of shoots ranging from 2
to 3 per explant, occurred in the explants incubated at the first step in medium with 22.4 and 0.198 μM IBA. Further growth and complete shoot formation occurred under incubation in a 16-h photoperiod. While keeping the culture
conditions constant and replacing BA with picloram (0.83–20.71 μM) in the initial step, adventious origin of cormlets occurred in 12% of the explants. However, when rhizome explants (also
obtained from shoots grown in liquid medium) were cultured with various growth regulators in the first step, medium containing
2,4,5-trichlorophenoxyacctic acid (7.82 μM) produced friable callus that re-differentiated into roots only. Physical forms of the medium, ie.e. agar-gelled or liquid,
imparted specific effects on the extent of multiplication of leaf-regenerated shoots with no differences in morphology and
growth patterns when compared to those of meristem-derived plants. 相似文献
7.
8.
Zhonghui Lu James J.-W. Duan Haiyun Xiao James Neels Dauh-Rurng Wu Carolyn A. Weigelt John S. Sack Javed Khan Max Ruzanov Yongmi An Melissa Yarde Ananta Karmakar Sureshbabu Vishwakrishnan Venkata Baratam Harisha Shankarappa Sridhar Vanteru Venkatesh Babu Mushkin Basha T.G. Murali Dhar 《Bioorganic & medicinal chemistry letters》2019,29(16):2265-2269
An X-ray crystal structure of one of our previously discovered RORγt inverse agonists bound to the RORγt ligand binding domain revealed that the cyclohexane carboxylic acid group of compound 2 plays a significant role in RORγt binding, forming four hydrogen bonding and ionic interactions with RORγt. SAR studies centered around the cyclohexane carboxylic acid group led to identification of several structurally diverse and more potent compounds, including new carboxylic acid analogues 7 and 20, and cyclic sulfone analogues 34 and 37. Notably, compounds 7 and 20 were found to maintain the desirable pharmacokinetic profile of 2. 相似文献
9.
Occurrence of genetic variants during micropropagation is occasionally encountered when the cultures are maintained in vitro for long period. Therefore, the micropropagated multiple shoots of Vanilla planifolia Andrews developed from axillary bud explants established 10 years ago were used to determine somaclonal variation using random amplified polymorphic DNA (RAPD) and intersimple sequence repeats markers (ISSR). One thousand micro-plants were established in soil of which 95 plantlets (consisting of four phenotypes) along with the mother plant were subjected to genetic analyses using RAPD and ISSR markers. Out of the 45 RAPD and 20 ISSR primers screened, 30 RAPD and 7 ISSR primers showed 317 clear, distinct and reproducible band classes resulting in a total of 30 115 bands. However, no difference was observed in banding patterns of any of the samples for a particular primer, indicating the absence of variation among the micropropagated plants. Our results allow us to conclude that the micropropagation protocol that we have used for in vitro proliferation of vanilla plantlets for the last 10 years might be applicable for the production of clonal plants over a considerable period of time. 相似文献
10.
Hairy root cultures of red beet, Beta vulgaris L., were permeabilized under the functions of food-grade chemical and biological agents cetyl trimethylammonium bromide (CTAB), Triton X-100, Tween-80, Lactobacillus helveticus, Saccharomyces cereviseae, and Candida utilis, as well as cell fractions of L. helveticus, for the recovery of betalaines with or without oxygen stress. Tween-80 (0.15%), Triton X-100 (0.2%), and CTAB (0.05%), in combination with oxygen stress, released 45%, 70%, and 90% pigment into the medium, respectively, with significantly lesser levels in agitated cultures receiving similar treatments. The release was rapid (1 h) in CTAB treatment with a much slower release in Tween-80. CTAB (0.002%) was found to be also useful in effluxing betalaines (80%) from hairy roots grown in a bubble column reactor. Viability of permeabilized hairy roots, tested on agar medium, was not affected by any level of CTAB treatment and was significantly retarded at higher levels of Triton X-100 and Tween-80. An altogether new approach of pigment release using biological agents such as live cells of food-grade microbes was used where C. utilis, L. helveticus, and S. cereviseae released 60%, 85%, and 54% betalaines, respectively, in 24 h, though lower level treatments also released similar levels of pigment by 48 h. Dried whole cell powder of L. helveticus, its total insoluble carbohydrate, and free lipid fractions released 10%, 0%, and 85% pigment, respectively. An extended study with a bubble column reactor using the free lipid fraction of L. helveticus showed 50% and 84% pigment release in 8 and 12 h, respectively, exhibiting good viability when plated on agar medium. Even in the bioreactor, replenishment of medium 8 h after treatment with free lipid of L. helveticus allowed regrowth of hairy roots. The high level of pigment release recorded here, using CTAB or lipid of L. helveticus, appears useful for developing processes for in situ recovery of betalaines. The live microbes, applicable only for batch cultures, are expected to impart improved sensory/nutraceutical effects to the recovered pigment and hence may add value to the product receiving the red beet pigment thus produced. 相似文献