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211.
Pritam Mohanty Shashikanta Behera Swasti S. Swain Durga P. Barik Soumendra K. Naik 《Physiology and Molecular Biology of Plants》2013,19(4):605-610
An optimized protocol was developed for in vitro plant regeneration of a medicinally important herb Hedychium coronarium J. Koenig using sprouted buds of rhizomes. The rhizomes with sprouted bud were inoculated on Murashige and Skoog (Physiol Plant 15:473–497, 1962) medium (MS) supplemented with either N6-benzyladenine (BA) alone (1.0–4.0 mg L−1) or in combination with 0.5 mg L−1 naphthalene acetic acid (NAA). Of these combinations, MS supplemented with a combination of 2.0 mg L−1 BA and 0.5 mg L−1 NAA was most effective. In this medium, best shoots (3.6) and roots (4.0) regeneration was observed simultaneously with an average shoot and root length of 4.7 cm and 4.2 cm respectively. Regeneration of shoots and roots in the same medium at the same time (One step shoot and root regeneration) reduced the time for production of in vitro plantlets and eliminates the media cost of rooting. Cent-percent (100 %) success in plant establishment was observed in both gradual acclimatization process as well as when plants were directly transferred to outdoor in clay pots containing a mixture of garden soil and sand (2:1) without any sequential acclimatization stage. 相似文献
212.
Sailabala?PadhiEmail author Prasanna?K.?Swain Sasmita?K.?Behura Sivaram?Baidya Santosh?K.?Behera Manas?R.?Panigrahy 《Journal of applied phycology》2011,23(2):151-155
The agarophyte red alga Gracilaria verrucosa occurs widely in Chilika Lake, one of the RAMSAR wetland sites in India. The lake is situated in the extreme southeast corner
of Orissa between latitudes 19°28′ and 19°54′ N and longitudes 85°06′ and 85°35′ E. The natural biomass production is not
sufficient for the agar industry, and the only alternative is to maximize the production of the seaweed through mass cultivation
by seaweed farming. To elucidate important aspects of the growth and development of G. verrucosa, experimental field cultivation was undertaken at Langaleswar and Samal sites of Chilika Lake using ropes and raft methods
during March to August, 2009. After 30 days of cultivation a maximum 15- and 13.8-fold increase in biomass in raft culture
and rope culture, respectively, was observed at Langaleswar and an 11.6- and 11.0-fold increase in biomass at Samal. Environmental
parameters such as temperature, salinity, pH, transparency, DO, conductivity, nitrate, and phosphate were monitored at both
stations, and the influence of environmental parameters is discussed. 相似文献
213.
Transforming growth factor-beta (TGF-β) is a multifunctional cytokine with multiple roles in the immune system. To date, it has been difficult to develop a comprehensive picture of the effect of TGF-β on T lymphocytes, because TGF-β not only acts directly on T lymphocytes, but also acts indirectly by regulating the function of antigen-presenting cells. In early studies, it was mostly the inhibitory function of TGF-β that was demonstrated; recently, however TGF-β was recognized as an antiapoptotic survival factor for T lymphocytes. The outcome of the TGF-β effect on T lymphocytes was shown to strongly depend on their stage of differentiation and on the cytokine milieu. TGF-β cannot be classified as a classical Th1 or Th2 cytokine. However, recently the existence of the TGF-β-producing Th3 subset was described which might play an important regulatory role during an immune response. A better understanding of the molecular mechanism of how TGF-β inhibits or stimulates T lymphocytes will help to predict the complex functions of this cytokine. 相似文献
214.
The number of patients age 65 and over at the Agnews State Hospital now constitutes over one-third of the resident population. The geriatric population is increasing in all California state hospitals.Because this is a relatively new area of concern for the psychiatric institution, the role of the state hospital in the care of the aged is not yet clearly defined.A pilot study of admissions in this age group committed from one county during a 12-month period was undertaken, with an attempt made to evaluate the suitability of the patient for commitment, as well as special problems in admission, treatment during hospitalization, and release from the hospital. The study indicated 42 per cent of persons admitted were considered unsuitable for commitment. Physical illness was found to be a major factor in precipitating admission and a predominating factor in the treatment program after admission. Almost 40 per cent of the patients died within a year after admission. 相似文献
215.
Persistent depots of influenza antigen fail to induce a cytotoxic CD8 T cell response 总被引:9,自引:0,他引:9
Jelley-Gibbs DM Dibble JP Brown DM Strutt TM McKinstry KK Swain SL 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(12):7563-7570
Encounter with Ag during chronic infections results in the generation of phenotypically and functionally heterogeneous subsets of Ag-specific CD8 T cells. Influenza, an acute infection, results in the generation of similar CD8 T cell heterogeneity, which may be attributed to long-lived depots of flu Ags that stimulate T cell proliferation well after virus clearance. We hypothesized that the heterogeneity of flu-specific CD8 T cells and maintenance of T cell memory required the recruitment of new CD8 T cells to persistent depots of flu Ag, as was the case for flu-specific CD4 T cell responses. However, robust expansion and generation of highly differentiated cytolytic effectors and memory T cells only occurred when naive CD8 T cells were primed during the first week of flu infection. Priming of new naive CD8 T cells after the first week of infection resulted in low numbers of poorly functional effectors, with little to no cytolytic activity, and a negligible contribution to the memory pool. Therefore, although the presentation of flu Ag during the late stages of infection may provide a mechanism for maintaining an activated population of CD8 T cells in the lung, few latecomer CD8 T cells are recruited into the functional memory T cell pool. 相似文献
216.
Silverstone AL Tseng TS Swain SM Dill A Jeong SY Olszewski NE Sun TP 《Plant physiology》2007,143(2):987-1000
The Arabidopsis (Arabidopsis thaliana) SPINDLY (SPY) protein negatively regulates the gibberellin (GA) signaling pathway. SPY is an O-linked N-acetylglucosamine (GlcNAc) transferase (OGT) with a protein-protein interaction domain consisting of 10 tetratricopeptide repeats (TPR). OGTs add a GlcNAc monosaccharide to serine/threonine residues of nuclear and cytosolic proteins. Determination of the molecular defects in 14 new spy alleles reveals that these mutations cluster in three TPRs and the C-terminal catalytic region. Phenotypic characterization of 12 spy alleles indicates that TPRs 6, 8, and 9 and the catalytic domain are crucial for GA-regulated stem elongation, floral induction, and fertility. TPRs 8 and 9 and the catalytic region are also important for modulating trichome morphology and inflorescence phyllotaxy. Consistent with a role for SPY in embryo development, several alleles affect seedling cotyledon number. These results suggest that three of the TPRs and the OGT activity in SPY are required for its function in GA signal transduction. We also examined the effect of spy mutations on another negative regulator of GA signaling, REPRESSOR OF ga1-3 (RGA). The DELLA motif in RGA is essential for GA-induced proteolysis of RGA, and deletion of this motif (as in rga-delta17) causes a GA-insensitive dwarf phenotype. Here, we demonstrate that spy partially suppresses the rga-delta17 phenotype but does not reduce rga-delta17 or RGA protein levels or alter RGA nuclear localization. We propose that SPY may function as a negative regulator of GA response by increasing the activity of RGA, and presumably other DELLA proteins, by GlcNAc modification. 相似文献
217.
Lourdes Mahilum-Tapay Vivian Laitila James J Wawrzyniak Helen H Lee Sarah Alexander Catherine Ison Alison Swain Penelope Barber Ines Ushiro-Lumb Beng T Goh 《BMJ (Clinical research ed.)》2007,335(7631):1190-1194
Objective To evaluate the performance of a new Chlamydia Rapid Test with vaginal swab specimens as a potential tool for chlamydia diagnosis and screening.Design Performance evaluation study.Settings A young people’s sexual health centre (site 1) and two genitourinary medicine clinics (sites 2 and 3) in the United Kingdom.Participants 1349 women aged between 16 and 54 attending one of the three clinics.Main outcome measures Sensitivity, specificity, positive predictive value, and negative predictive value of the Chlamydia Rapid Test versus polymerase chain reaction and strand displacement amplification assays; correlation between the Chlamydia Rapid Test visual signal and organism load; acceptability to participants of self collected vaginal swabs as the specimen type for Chlamydia testing.Results Polymerase chain reaction positivity rates for Chlamydia trachomatis infection were 8.4% (56/663) at site 1, 9.4% (36/385) at site 2, and 6.0% (18/301) at site 3. Compared with polymerase chain reaction assay, the resolved sensitivity, specificity, positive predictive value, and negative predictive value of the Chlamydia Rapid Test were 83.5% (91/109), 98.9% (1224/1238), 86.7% (91/105), and 98.6% (1224/1242). Compared with strand displacement amplification assay, sensitivity and specificity of the Chlamydia Rapid Test were 81.6% (40/49) and 98.3% (578/588). Organism load of self collected vaginal swabs ranged from 5.97×102 to 1.09×109 Chlamydia plasmids per swab, which correlated well with the Chlamydia Rapid Test’s visual signal (r=0.6435, P<0.0001). Most (95.9%) surveyed participants felt comfortable about collecting their own swabs.Conclusions The performance of the Chlamydia Rapid Test with self collected vaginal swabs indicates that it would be an effective same day diagnostic and screening tool for Chlamydia infection in women. The availability of Chlamydia Rapid Test results within 30 minutes allows for immediate treatment and contact tracing, potentially reducing the risks of persistent infection and onward transmission. It could also provide a simple and reliable alternative to nucleic acid amplification tests in chlamydia screening programmes. 相似文献
218.
Hutchings JA Swain DP Rowe S Eddington JD Puvanendran V Brown JA 《Proceedings. Biological sciences / The Royal Society》2007,274(1619):1693-1699
Neither the scale of adaptive variation nor the genetic basis for differential population responses to the environment is known for broadcast-spawning marine fishes. Using a common-garden experimental protocol, we document how larval growth, survival and their norms of reaction differ genetically among four populations of Atlantic cod (Gadus morhua). These traits, and their plastic responses to food and temperature, differed across spatial scales at which microsatellite DNA failed to detect population structure. Divergent survival reaction norms indicate that warm-water populations are more sensitive to changes in food, whereas cold-water populations are more sensitive to changes in temperature. Our results suggest that neither the direction nor the magnitude of demographic responses to environmental change need be the same among populations. Adaptive phenotypic plasticity, previously undocumented in marine fishes, can significantly influence the probability of recovery and persistence of collapsed populations by affecting their ability to respond to natural and anthropogenic environmental change. 相似文献
219.
Jack X. Q. Pang Scott Zimmer Sophia Niu Pam Crotty Jenna Tracey Faruq Pradhan Abdel Aziz M. Shaheen Carla S. Coffin Steven J. Heitman Gilaad G. Kaplan Mark G. Swain Robert P. Myers 《PloS one》2014,9(4)
Background
Liver stiffness measurement (LSM) by transient elastography (TE, FibroScan) is a validated method for noninvasively staging liver fibrosis. Most hepatic complications occur in patients with advanced fibrosis. Our objective was to determine the ability of LSM by TE to predict hepatic complications and mortality in a large cohort of patients with chronic liver disease.Methods
In consecutive adults who underwent LSM by TE between July 2008 and June 2011, we used Cox regression to determine the independent association between liver stiffness and death or hepatic complications (decompensation, hepatocellular carcinoma, and liver transplantation). The performance of LSM to predict complications was determined using the c-statistic.Results
Among 2,052 patients (median age 51 years, 65% with hepatitis B or C), 87 patients (4.2%) died or developed a hepatic complication during a median follow-up period of 15.6 months (interquartile range, 11.0–23.5 months). Patients with complications had higher median liver stiffness than those without complications (13.5 vs. 6.0 kPa; P<0.00005). The 2-year incidence rates of death or hepatic complications were 2.6%, 9%, 19%, and 34% in patients with liver stiffness <10, 10–19.9, 20–39.9, and ≥40 kPa, respectively (P<0.00005). After adjustment for potential confounders, liver stiffness by TE was an independent predictor of complications (hazard ratio [HR] 1.05 per kPa; 95% confidence interval [CI] 1.03–1.06). The c-statistic of liver-stiffness for predicting complications was 0.80 (95% CI 0.75–0.85). A liver stiffness below 20 kPa effectively excluded complications (specificity 93%, negative predictive value 97%); however, the positive predictive value of higher results was sub-optimal (20%).Conclusions
Liver stiffness by TE accurately predicts the risk of death or hepatic complications in patients with chronic liver disease. TE may facilitate the estimation of prognosis and guide management of these patients. 相似文献220.
Cooper LC Chicchi GG Dinnell K Elliott JM Hollingworth GJ Kurtz MM Locker KL Morrison D Shaw DE Tsao KL Watt AP Williams AR Swain CJ 《Bioorganic & medicinal chemistry letters》2001,11(9):1233-1236
The synthesis and biological evaluation of a series of 2-aryl indoles with high affinity for the human neurokinin-1 (hNK1) receptor are reported, concentrating on optimisation of the indole substitution. 相似文献