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Janhvi Mishra Himani Bhandari Mahendra Singh Sandeep Rawat R. K. Agnihotri S. Mishra S. Purohit 《Acta Physiologiae Plantarum》2011,33(5):1841-1846
Picrorhiza kurroa Royle ex Benth. is an endangered plant producing various compounds of medicinal importance. Hairy roots of P. kurroa were obtained following cocultivation of shoot tip explants with Agrobacterium rhizogenes strains A 4 and PAT 405. Bacterial strain A 4 appeared to be better than the strain PAT 405 in terms of both growth of respective
hairy root cultures and secondary metabolite production. The optimal growth of both the hairy root cultures occurred on half-strength
semisolid medium with 3% sucrose. Picrotin and picrotoxinin from the roots of wild type field grown plants were compared with
8-week-old hairy root cultures induced by the A 4 and PAT 405 strains of A. rhizogenes. Picrotin and picrotoxinin content were evaluated in hairy root cultures as well as roots of field grown plant of P. kurroa. In terms of the production of picrotin and picrotoxinin, the A 4 induced hairy roots appeared to be a better performer than
the PAT 405 induced hairy root cultures. The picrotin and picrotoxinin content was highest in 8-week-old A 4 induced hairy
roots (8.8 μg/g DW and 47.1 μg/g DW, respectively). Rapid growth of the hairy roots of P. kurroa with in vitro secondary metabolite production potential may offer an attractive alternative to the exploitation of this endangered
plant species. 相似文献
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55.
Samantaray S Smith JA Das A Matzelle DD Varma AK Ray SK Banik NL 《Neurochemical research》2011,36(10):1809-1816
Spinal cord injury (SCI), depending on the severity of injury, leads to neurological dysfunction and paralysis. Methylprednisolone,
the only currently available therapy renders limited protection in SCI. Therefore, other therapeutic agents must be tested
to maximize neuroprotection and functional recovery. Previous data from our laboratory indicate that estrogen (17β-estradiol)
at a high dose may attenuate multiple damaging pathways involved in SCI and improve locomotor outcome. Since use of high dose
estrogen may have detrimental side effects and therefore may never be used in the clinic, the current study investigated the
efficacy of this steroid hormone at very low doses in SCI. In particular, we tested the impact of dosing (1–10 μg/kg), mode
of delivery (intravenous vs. osmotic pump), and delay in estrogen application (15 min–4 h post-SCI) on microgliosis and neuronal
death in acute SCI in rats. Treatment with 17β-estradiol (1–10 μg/kg) significantly reduced microglial activation and also
attenuated apoptosis of neurons compared to untreated SCI animals. The attenuation of cell death and inflammation by estrogen
was observed regardless of mode and time of delivery following injury. These findings suggest estrogen as a potential agent
for the treatment of individuals with SCI. 相似文献
56.
Selenium availability in berseem (Trifolium alexandrinum) as affected by selenium and phosphorus application 总被引:1,自引:0,他引:1
Summary The effect of selenium and phosphorus application on Berseem (Trifolium alexandrium) was studied in the green house. Each dose of selenium from O to 16 ppm decreased the dry matter yield of Berseem significantly at all the levels of applied phosphorus. Phosphorus stimulated the dry matter yield at all levels of selenium. Yields in the second cutting were of a higher order than in the first cut. Selenium application increased selenium and phosphorus content in Berseem, but at 8 and 16 ppm of selenium the phosphorus content decreased significantly. Sulphur concentration decreased with selenium application but application of phosphorus increased sulphur concentration showing synergetic effect.Studies on residual effect of selenium revealed that the application of 50 ppm of phosphorus increased the yield while that of 100 ppm decreased it. Selenium concentration which increased with increasing phosphorus was many fold higher in the first cutting than in the second cutting and similar was the trend with phosphorus and sulphur. 相似文献
57.
Equilibrium parameters for the binding of monodisperse alkyl sulfate along the i-face (the interface binding surface) of pig pancreatic IB phospholipase A(2) (PLA2) to form the premicellar complexes (E(i)(#)) are characterized to discern the short-range specific interactions. Typically, E(i)(#) complexes are reversible on dilution. The triphasic binding isotherm, monitored as the fluorescence emission from the single tryptophan of PLA2, is interpreted as a cooperative equilibrium for the sequential formation of three premicellar complexes (E(i)(#), i = 1, 2, 3). In the presence of calcium, the dissociation constant K(1) for the E(1)(#) complex of PLA2 with decyl sulfate (CMC = 4500 microM) is 70 microM with a Hill coefficient n(1) = 2.1 +/- 0.2; K(2) for E(2)(#) is 750 microM with n(2) = 8 +/- 1, and K(3) for E(3)(#) is 4000 microM with an n(3) value of about 12. Controls show that (a) self-aggregation of decyl sulfate alone is not significant below the CMC; (b) occupancy of the active site is not necessary for the formation of E(i)(#); (c) K(i) and n(i) do not change significantly due to the absence of calcium, possibly because alkyl sulfate does not bind to the active site of PLA2; (d) the E(i)(#) complexes show a significant propensity for aggregation; and (e) PLA2 is not denatured in E(i)(#). The results are interpreted to elaborate the model for atomic level interactions along the i-face: The chain length dependence of the fit parameters suggests that short-range specific anion binding of the headgroup is accompanied by desolvation of the i-face of E(i)(#). We suggest that allosteric activation of PLA2 results from such specific interactions of the amphiplies and the desolvation of the i-face. The significance of these primary interfacial binding events and the coexistence of the E and E(i)(#) aggregates is discussed. 相似文献
58.
Mahendra K. Jain Fausto Ramirez Terence M. McCaffrey Panayiotis V. Ioannou James F. Marecek J. Leunissen-Bijvelt 《生物化学与生物物理学报:生物膜》1980,600(3):678-688
Aqueous dispersions of monovalent and divalent cation salts of O-(1,2-dipalmitoyl-sn-glycero-3-phosphoryl) cholesterol form multilamellar vesicles as shown by freeze-fracture electron microscopy, by electron micrographs of the negatively stained liposomes, and by swelling curves of liposomes in hypoosmotic medium. Differential scanning calorimetry reveals that aqueous dispersions of divalent metal salts of O-(1,2-dipalmitoyl-sn-glycero-3-phosphoryl)-cholesterol undergo a characteristic thermotropic phase transition with a relatively large cooperative unit (n > 250 for the calcium salt). In contrast, monovalent cation salts of O-(1,2-dipalmitoyl-sn-glycerol-3-phosphoryl)cholesterol do not show a thermotropic phase transition under comparable conditions. The molecular area of O-(1,2-dipalmitoyl-sn-glycero-3-phosphoryl)cholesterol in a monolayer is the same in the presence and absence of Ca2+, and is virtually equal to the area of an equimolar mixture of dipalmitoyl phosphatidic acid and cholesterol. To account for the novel state induced by Ca2+ on aqueous dispersions of O-(1,2-dipalmitoyl-sn-glycero-3-phosphoryl)cholesterol (i.e., bilayer organization and highly cooperative phase transition), a linear array model is proposed in which Ca2+ bridges adjacent arrays of O-(1,2-dipalmitoyl-sn-glycero-3-phosphoryl)cholesterol molecules, thus freezing the acyl chains in their normal state. One of the main corollaries of the model is that the cooperative unit for a thermotropic phase transition is essentially one-dimensional, rather than a two-dimensional matrix. O-(1,2-Dipalmitoyl-sn-glycero-3-phosphoryl)cholesterol is proposed as an orientationally and conformationally restricted analog of glycerophospholipid plus cholesterol in bilayers. 相似文献
59.
Yi Sun Mahendra S. Rao Richard E. Zigmond Story C. Landis 《Developmental neurobiology》1994,25(4):415-430
Vasoactive intestinal peptide (VIP) expression increases in sympathetic neurons when they are grown in dissociated cell or explant cultures and when they are axotomized in vivo. In dissociated cell culture, the magnitude of the VIP increase was reduced when nonneuronal cells were removed and medium conditioned by ganglionic nonneuronal cells increased VIP in neuron-enriched cultures. Antiserum Against cholinergic differentiation factor (also leukemia inhibitory factor; CDF/LIF), but not against ciliary neurotrophic factor, immunoprecipitated this activity. Medium conditioned by sympathetic ganglion explants also contained a VIP-stimulatory molecule that was immunoprecipitated by CDF/LIF antiserum, and CDF/LIF antiserum partially blocked VIP induction in explants. CDF/LIF mRNA was increased in dissociated cell cultures, in ganglion explants and in vivo after axotomy. Our results suggest that CDF/LIF released from ganglionic nonneuronal cells plays an important role in regulating VIP after axotomy. 1994 John Wiley & Sons, Inc. 相似文献
60.
Aparajita Das Swati Tripathi Ajit Varma 《World journal of microbiology & biotechnology》2014,30(3):1075-1084
The present study was conducted for optimization of in vitro substrates under aseptic conditions for interaction of Piriformospora indica with the medicinal plant Coleus forskohlii. It aims to test the effects of different substrates on P. indica colonization as well as growth parameters of the in vitro raised C. forskohlii. Interaction of in vitro C. forskohlii with root endophyte P. indica under aseptic condition resulted in increase in growth parameters in fungus colonized plants. It was observed that P. indica promoted the plant’s growth in all irrespective of substrates used for co-culture study. The growth was found inferior in liquid compared to semisolid medium as well as there was problem of hyperhydricity in liquid medium. P. indica treated in vitro plantlets were better adapted for establishment under green house compared to the non treated plants due to fungal intervention. 相似文献