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141.
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143.
Archna Suman Sushil Kumar R. B. Rewari Suman P. S. Khanuja 《Journal of plant biochemistry and biotechnology.》1995,4(1):5-9
Six heat shock tolerant mutants of Rhizobium meliloti Rmd201 were isolated through transposon Tn5 mutagenesis. The symbiotic assays of these mutants with alfalfa plants, showed four of these mutants to be affected in nitrogenase effectivity also. These four mutants could be classified into two separate complementation groups hssA and hssC through R-prime mediated merodiploid constructions. The hssC mutant Rmd1040 also showed poor interaction with phages indicating surface alterations. The results indicated possible involvement of these loci in symbiosis as well as heat shock response. 相似文献
144.
Commercialization of plant tissue culture in India 总被引:2,自引:0,他引:2
Commercial application of plant tissue culture started in USA with micropropagation of orchids in 1970s. It has seen tremendous
expansion globally from 1985 to 1990 in the number of production units as well as the number of plants produced. With an estimated
global market of 15 billion US dollars per annum for tissue cultured products, even with exponential expansion in the industry,
the demand far exceeds production, leaving enough scope for expansion. This industry appears to be undergoing a pause in growth
presently in developed countries as it is finding difficult to remain cost–effective. In US, only half the production capacity
is being utilized currently due to high labour costs. In developing countries, with lower wage scales, plants are being produced
at much cheaper rates. Indian micropropagation industry, though a late starter by almost a decade, compared to its western
counterparts, has expanded exponentially from 5 million annual capacity in 1988 to 190 million in 1996. The facilities now
created are at par with the best in leading countries like the Netherlands and USA. To remain in profitable business and to
earn the much needed foreign exchange, Indian units need to judiciously mix steady revenue generating items with unique speciality
items based on demand in domestic and international markets.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
145.
Soibam Purnima Devi Suman Kumaria Satyawada Rama Rao Pramod Tandon 《Tropical plant biology》2016,9(4):267-279
Carnivorous plants are among the curiosities of nature being different from the normal plants in their mode of nutrition. These plants have fascinated several researchers for centuries. They are also characterized by synthesis of bioactive compounds which are used as a mechanism for self defense. These compounds possess a broad spectrum of biological activities such as antiparasitic, antibacterial, insecticidal, fungicidal, anti-inflammatory, antipyretic, antiproliferative activities. Although, several antimicrobial drugs have been introduced during the recent decades, the problems of microbial infections resistant to synthetic pesticides still exist which necessitate the introduction of novel antimicrobial agents with additional modes of actions than the currently available therapeutic agents. Naphthoquinones are one of the most studied bioactive compounds which have been reported to inhibit the growth of proliferative cells and microbes. Efforts have been made to induce the biosynthesis of naphthoquinone in different species of carnivorous plants. It has been demonstrated that the accumulation of naphthoquinones in carnivorous plants was increased by injecting chitin into the plant tissues. Also, their biosynthesis could be enhanced by the incorporation of elicitors in in vitro cultures of plants. In the present review, we discuss the applications of naphthoquinones and its biosynthesis in carnivorous plants. 相似文献
146.
Mira C. Patel Wei Wang Lioubov M. Pletneva Seesandra V. Rajagopala Yi Tan Tina V. Hartert Marina S. Boukhvalova Stefanie N. Vogel Suman R. Das Jorge C. G. Blanco 《PloS one》2016,11(11)
In recent years, there has been a significant increase in detection of Enterovirus D-68 (EV-D68) among patients with severe respiratory infections worldwide. EV-D68 is now recognized as a re-emerging pathogen; however, due to lack of a permissive animal model for EV-D68, a comprehensive understanding of the pathogenesis and immune response against EV-D68 has been hampered. Recently, it was shown that EV-D68 has a strong affinity for α2,6-linked sialic acids (SAs) and we have shown previously that α2,6-linked SAs are abundantly present in the respiratory tract of cotton rats (Sigmodon hispidus). Thus, we hypothesized that cotton rats could be a potential model for EV-D68 infection. Here, we evaluated the ability of two recently isolated EV-D68 strains (VANBT/1 and MO/14/49), along with the historical prototype Fermon strain (ATCC), to infect cotton rats. We found that cotton rats are permissive to EV-D68 infection without virus adaptation. The different strains of EV-D68 showed variable infection profiles and the ability to produce neutralizing antibody (NA) upon intranasal infection or intramuscular immunization. Infection with the VANBT/1 resulted in significant induction of pulmonary cytokine gene expression and lung pathology. Intramuscular immunization with live VANBT/1 or MO/14/49 induced strong homologous antibody responses, but a moderate heterologous NA response. We showed that passive prophylactic administration of serum with high content of NA against VANBT/1 resulted in an efficient antiviral therapy. VANBT/1-immunized animals showed complete protection from VANBT/1 challenge, but induced strong pulmonary Th1 and Th2 cytokine responses and enhanced lung pathology, indicating the generation of exacerbated immune response by immunization. In conclusion, our data illustrate that the cotton rat is a powerful animal model that provides an experimental platform to investigate pathogenesis, immune response, anti-viral therapies and vaccines against EV-D68 infection. 相似文献
147.
G. Tettamanti A. Preti A. Lombardo T. Suman V. Zambotti 《Journal of neurochemistry》1975,25(4):451-456
—The activity of brain membrane-bound neuraminidase on endogenous and exogenous substrates was comparatively studied in various animals (rat, chicken, rabbit, pig, calf and human). The maximum rate of hydrolysis of endogenous substrates by membrane-bound neuraminidase (using a crude preparation of the enzyme) was different in the various animals (from 0·05 to 0·73 units, referred to 1 mg protein) and was obtained under similar but not identical optimum conditions (pH from 4·1 to 5·1; requirement or not of Triton X-100). The maximum degree of hydrolysis of endogenous substates was also different (from 15 to 27 nmol released NeuNAc/mg protein) and was obtained within different incubation periods (from 2 to 18 h). It corresponded (in rabbit, calf, human brain only), or not, to the actual exhaustion of the endogenous substrates. The endogenous substrates were recognized as both gangliosides and sialoglycoproteins. The extent of hydrolysis of sialoglycoproteins varied from 1·5% in rabbit to 15·6% in chicken brain; the hydrolysis of gangliosides (ranging from 14·1% in pig to 53·7% in rabbit brain) reached only in some animals (rabbit, calf, human) the complete transformation of major oligosialogangliosides into the neuraminidase resistant monosialoganglioside GMI. Upon addition of exogenous substrates (sialyl-lactose, ganglioside GD1a, brain sialopeptides, ovine submaxillary mucin) the actual rate of liberation of total NeuNAc (from both endogenous and exogenous substrates) considerably exceeded, although at a different extent (depending on the animal and on the added substrate used) the rate of hydrolysis of sole endogenous substrates. The possibility of an accurate assay of brain membrane-bound neuraminidase in a crude enzyme preparation is evaluated and guidelines for the assay procedure suggested. 相似文献
148.
Summary A patient with partial trisomy 22 (PT22) is presented. Inheritance is presumed to be due to secondary nondisjunction in her mother, who has a balanced translocation t(11;22)(q25;q13). The problem of the phenotypic heterogeneity observed with this chromosome change is discussed. 相似文献
149.
Naveen Kumar MSc PhD Scholar Srinu Reddi PhD Savita Devi MSc PhD Sanusi Bello Mada PhD Rajeev Kapila PhD Suman Kapila PhD 《Journal of cellular biochemistry》2019,120(6):9677-9691
Prolonged passaging of primary fibroblast cells totally shapes the natural biological phenomena and leads to the appearance of features related to senescence. As a result, it is a good natural tool to delineate the molecular mechanism of cellular aging. The present investigation revealed the antiaging effect of milk-derived novel bioactive peptide (VLPVPQK). The peptide played an important role in downregulating apoptosis-related markers in late passages of cultured fibroblast cells. The peptide treatment to aged fibroblasts caused enhancement in cell migration, DNA integrity, and decrease in the lipid peroxidation, reactive oxygen species, nitric oxide production as well as pro-inflammatory cytokines, TNF-α and IL-6. Moreover, the peptide decreased the expression of apoptotic caspases, Bax, and senescence-associated β-galactosidase (SA-β-gal) proteins. The peptide pretreatment also enhanced the extracellular collagen protein and antiapoptotic, Bcl-xL. In addition, the peptide treatment reversed the senescence-related activity in fibroblasts by stimulating Nrf2 mediated antioxidative defense system and inhibiting the action of NFkB/p38MAPK signaling, similar to the commercially available inhibitor (SB203580) of p38MAPK. Thus, the peptide exhibits the antiaging effect in dermal fibroblast cells. 相似文献
150.