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91.
Plant growth promoting Pantoea agglomerans NBRISRM (NBRISRM) was able to produce 60.4 μg/ml indole acetic acid and solubilize 77.5 μg/ml tri-calcium phosphate under
in vitro conditions. Addition of 2% NaCl (w/v) in the media induced the IAA production and phosphate solubilization by 11%
and 7%, respectively. For evaluating the plant growth promotory effect of NBRISRM inoculation a micro plot trial was conducted
using maize and chickpea as host plants. The results revealed significant increase in all growth parameters tested in NBRISRM
inoculated maize and chickpea plants, which were further confirmed by higher macronutrients (N, P and K) accumulation as compared
to un-inoculated controls. Throughout the growing season of maize and chickpea, rhizosphere population of NBRISRM were in
the range 107–108 CFU/g soil and competing with 107–109 CFU/g soil with heterogeneous bacterial population. Functional richness, diversity, and evenness were found significantly
higher in maize rhizosphere as compared to chickpea, whereas NBRISRM inoculation were not able to change it, in both crops
as compared to their un-inoculated control. To the best of our knowledge this is first report where we demonstrated the effect
of P. agglomerans strain for improving maize and chickpea growth without altering the functional diversity. 相似文献
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93.
Mikus CR Fairfax ST Libla JL Boyle LJ Vianna LC Oberlin DJ Uptergrove GM Deo SH Kim A Kanaley JA Fadel PJ Thyfault JP 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,111(3):657-664
The vasodilatory effects of insulin account for up to 40% of insulin-mediated glucose disposal; however, insulin-stimulated vasodilation is impaired in individuals with type 2 diabetes, limiting perfusion and delivery of glucose and insulin to target tissues. To determine whether exercise training improves conduit artery blood flow following glucose ingestion, a stimulus for increasing circulating insulin, we assessed femoral blood flow (FBF; Doppler ultrasound) during an oral glucose tolerance test (OGTT; 75 g glucose) in 11 overweight or obese (body mass index, 34 ± 1 kg/m2), sedentary (peak oxygen consumption, 23 ± 1 ml·kg?1·min?1) individuals (53 ± 2 yr) with non-insulin-dependent type 2 diabetes (HbA1c, 6.63 ± 0.18%) before and after 7 days of supervised treadmill and cycling exercise (60 min/day, 60-75% heart rate reserve). Fasting glucose, insulin, and FBF were not significantly different after 7 days of exercise, nor were glucose or insulin responses to the OGTT. However, estimates of whole body insulin sensitivity (Matsuda insulin sensitivity index) increased (P < 0.05). Before exercise training, FBF did not change significantly during the OGTT (1 ± 7, -7 ± 5, 0 ± 6, and 0 ± 5% of fasting FBF at 75, 90, 105, and 120 min, respectively). In contrast, after exercise training, FBF increased by 33 ± 9, 39 ± 14, 34 ± 7, and 48 ± 18% above fasting levels at 75, 90, 105, and 120 min, respectively (P < 0.05 vs. corresponding preexercise time points). Additionally, postprandial glucose responses to a standardized breakfast meal consumed under "free-living" conditions decreased during the final 3 days of exercise (P < 0.05). In conclusion, 7 days of aerobic exercise training improves conduit artery blood flow during an OGTT in individuals with type 2 diabetes. 相似文献
94.
Several different classes of growth factor receptors containing tyrosine kinases (RTK) are directly or indirectly involved in angiogenesis. Inhibition of these RTKs has provided a new paradigm in the treatment of tumors by restricting their growth and metastasis. We have designed, synthesized and evaluated eleven novel 2-amino-4-(3-bromoanilino)-6-substituted benzyl pyrrolo[2,3-d]pyrimidines as the first in a series of RTK inhibitors. These analogues were synthesized from appropriate alpha-bromomethylbenzyl ketones by cyclocondensation with 2,6-diamino-4-pyrimidone to afford the 2-amino-4-oxo-6-substituted benzyl pyrrolo[2,3-d]pyrimidines. Chlorination of the 4-position followed by displacement with 3-bromoaniline afforded the target compounds. In some instances, the 2-amino moiety of the pyrrolo[2,3-d]pyrimidines was protected prior to the chlorination and displacement followed by deprotection. The compounds were evaluated as inhibitors of vascular endothelial growth factor receptors VEGFR-2 (Flk-1, KDR) and VEGFR-1 (Flt-1); epidermal growth factor receptor (EGFR); and platelet-derived growth factor receptor-beta (PDGFR-beta). Selected compounds were also evaluated against the growth of A431 cells (which overexpress EGFR) in culture and as inhibitors of angiogenesis in the chicken embryo chorioallantonic membrane (CAM) assay. In each evaluation, a known standard compound was used as a comparison. Of the 11 analogues, five were more potent or equipotent as compared to standard compounds against the growth factor receptors. Two analogues showed superior inhibition of A431 cells in culture compared to the standard compounds. Three analogues were equipotent with the standard compound in the CAM assay and four of the analogues were dual inhibitors of RTKs. The structure-activity relationship for inhibition of different RTKs was quite distinct and different, and for VEGFR-2 and EGFR diametrically opposite. The inhibitory data against the RTKs in this study demonstrates that variation of the substituent(s) in the benzyl ring of these 2-amino-4-anilino 6-benzyl pyrrolo[2,3-d]pyrimidines does indeed control both the potency and specificity of inhibitory activity against RTKs. 相似文献
95.
96.
Anjana Rustagi Deepak Kumar Shashi Shekhar Mohd Aslam Yusuf Santosh Misra Neera Bhalla Sarin 《Molecular biotechnology》2014,56(6):535-545
Cationic antimicrobial peptides (CAPs) have shown potential against broad spectrum of phytopathogens. Synthetic versions with desirable properties have been modeled on these natural peptides. MsrA1 is a synthetic chimera of cecropin A and melittin CAPs with antimicrobial properties. We generated transgenic Brassica juncea plants expressing the msrA1 gene aimed at conferring fungal resistance. Five independent transgenic lines were evaluated for resistance to Alternaria brassicae and Sclerotinia sclerotiorum, two of the most devastating pathogens of B. juncea crops. In vitro assays showed inhibition by MsrA1 of Alternaria hyphae growth by 44–62 %. As assessed by the number and size of lesions and time taken for complete leaf necrosis, the Alternaria infection was delayed and restricted in the transgenic plants with the protection varying from 69 to 85 % in different transgenic lines. In case of S. sclerotiorum infection, the lesions were more severe and spread profusely in untransformed control compared with transgenic plants. The sclerotia formed in the stem of untransformed control plants were significantly more in number and larger in size than those present in the transgenic plants where disease protection of 56–71.5 % was obtained. We discuss the potential of engineering broad spectrum biotic stress tolerance by transgenic expression of CAPs in crop plants. 相似文献
97.
Mahawar M Atianand MK Dotson RJ Mora V Rabadi SM Metzger DW Huntley JF Harton JA Malik M Bakshi CS 《The Journal of biological chemistry》2012,287(30):25216-25229
Francisella tularensis, the causative agent of tularemia, is one of the deadliest agents of biological warfare and bioterrorism. Extremely high virulence of this bacterium is associated with its ability to dampen or subvert host innate immune response. The objectives of this study were to identify factors and understand the mechanisms of host innate immune evasion by F. tularensis. We identified and explored the pathogenic role of a mutant interrupted at gene locus FTL_0325, which encodes an OmpA-like protein. Our results establish a pathogenic role of FTL_0325 and its ortholog FTT0831c in the virulent F. tularensis SchuS4 strain in intramacrophage survival and suppression of proinflammatory cytokine responses. This study provides mechanistic evidence that the suppressive effects on innate immune responses are due specifically to these proteins and that FTL_0325 and FTT0831c mediate immune subversion by interfering with NF-κB signaling. Furthermore, FTT0831c inhibits NF-κB activity primarily by preventing the nuclear translocation of p65 subunit. Collectively, this study reports a novel F. tularensis factor that is required for innate immune subversion caused by this deadly bacterium. 相似文献
98.
Cross-linking of the IgE receptor (FcεRI) on mast cells plays a critical role in IgE-dependent allergy, including allergic rhinitis, asthma, anaphylaxis, and immediate-type hypersensitivity reactions. Previous studies have demonstrated that the K(+) channel, KCa3.1, plays a critical role in IgE-stimulated Ca(2+) entry and degranulation in both human and mouse mast cells. We now have shown that the class II phosphatidylinositol-3-kinase C2β (PI3KC2β) is necessary for FcεRI-stimulated activation of KCa3.1, Ca(2+) influx, cytokine production, and degranulation of bone marrow-derived mast cells (BMMC). In addition, we found that the E3 ubiquitin ligase, tripartite motif containing protein 27 (TRIM27), negatively regulates FcεRI activation of KCa3.1 and downstream signaling by ubiquitinating and inhibiting PI3KC2β. TRIM27(-/-) mice are also more susceptible in vivo to acute anaphylaxis. These findings identify TRIM27 as an important negative regulator of mast cells in vivo and suggest that PI3KC2β is a potential new pharmacologic target to treat IgE-mediated disease. 相似文献
99.
100.
H. S. Shekhar Sharma Colin Fleming Chris Selby J. R. Rao Trevor Martin 《Journal of applied phycology》2014,26(1):465-490
A biostimulant is an organic material that, when applied in small quantities, enhances plant growth and development such that the response cannot be attributed to the application of traditional plant nutrients. This review is aimed at highlighting developments in the processing of macroalgae for agricultural biostimulants (AB), summarising the biologically active components of brown macroalgae and examining the factors supporting the use of macroalgal AB for managing abiotic and biotic stresses in crop plants. The policy drivers supporting the use of macroalgal-derived ABs in agriculture are also emphasised. We examine the use of macroalgal ABs in crop production and evaluated the benefits of seed priming, foliar application, soil drenches and hydroponic treatments. The use of macroalgal ABs on crop plants can generate multiple benefits with reported effects including enhanced rooting, higher crop and fruit yields, freezing, drought and salt tolerance, enhanced photosynthetic activity and resistance to fungi, bacteria and virus. ABs can be applied as an alternative, or used in conjunction with synthetic crop protection products and plant growth regulators, and may have a role in maintaining crop production levels, health and quality in the future when many active ingredients will be lost to the industry due to changes in European Union regulations. Worldwide, macroalgae remain largely unexploited, we highlight some of the future research and development priorities. 相似文献