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111.
Background
Recent studies have demonstrated marked international variations in the prevalence of asthma, but less is known about ethnic variations in asthma epidemiology within individual countries and in particular the impact of migration on risk of developing asthma. Recent within country comparisons have however revealed that despite originating from areas of the world with a low risk for developing asthma, South Asian and Afro-Caribbean people in the UK are significantly (3× and 2× respectively) more likely to be admitted to hospital for asthma related problems than Whites.Methods
Using data from the Fourth National Study of Morbidity Statistics in General Practice, a one-percent broadly representative prospective cohort study of consultations in general practice, we investigated ethnic variations in incident asthma consultations (defined as new or first consultations), and compared consultation rates between those born inside and outside the UK (migrant status). Logistic regression models were used to examine the combined effects of ethnicity and migration on asthma incident consultations.Results
Results showed significantly lower new/first asthma consultation rates for Whites than for each of the ethnic minority groups studied (mean age-adjusted consultation rates per 1000 patient-years: Whites 26.4 (95%CI 26.4, 26.4); South Asians 30.4 (95%CI 30.3, 30.5); Afro-Caribbeans 35.1 (95%CI 34.9, 35.3); and Others 27.8 (27.7, 28.0). Within each of these ethnic groups, those born outside of the UK showed consistently lower rates of incident asthma consultations. Modelling the combined effects of ethnic and migrant status revealed that UK-born South Asians and Afro-Caribbeans experienced comparable risks for incident GP consultations for asthma to UK-born Whites. Non-UK born Whites however experienced reduced risks (adjusted OR 0.82, 95%CI 0.69, 0.97) whilst non-UK born South Asians experienced increased risks (adjusted OR 1.33, 95%CI 1.04, 1.70) compared to UK-born Whites.Conclusion
These findings strongly suggest that ethnicity and migration have significant and independent effects on asthma incidence. The known poorer asthma outcomes in UK South Asians and Afro-Caribbeans may in part be explained by the offspring of migrants experiencing an increased risk of developing asthma when compared to UK-born Whites. This is the first study to find heterogeneity for incident asthma consultations in Whites by migrant status. 相似文献112.
Comparison of probabilistic combination methods for protein secondary structure prediction 总被引:2,自引:0,他引:2
Liu Y Carbonell J Klein-Seetharaman J Gopalakrishnan V 《Bioinformatics (Oxford, England)》2004,20(17):3099-3107
MOTIVATION: Protein secondary structure prediction is an important step towards understanding how proteins fold in three dimensions. Recent analysis by information theory indicates that the correlation between neighboring secondary structures are much stronger than that of neighboring amino acids. In this article, we focus on the combination problem for sequences, i.e. combining the scores or assignments from single or multiple prediction systems under the constraint of a whole sequence, as a target for improvement in protein secondary structure prediction. RESULTS: We apply several graphical chain models to solve the combination problem and show that they are consistently more effective than the traditional window-based methods. In particular, conditional random fields (CRFs) moderately improve the predictions for helices and, more importantly, for beta sheets, which are the major bottleneck for protein secondary structure prediction. 相似文献
113.
K. S. Mohan R. Asokan C. Gopalakrishnan 《Journal of plant biochemistry and biotechnology.》1997,6(2):105-109
Commercial formulations of Bacillus thuringiensis subsp. kurstaki (Btk) consisting of insecticidal crystals and endospores are being extensively used by farmers in Karnataka for the control of insect pests on cabbage and cauliflower. The endospores of Btk persist in soil and are infectious to the mulberry silkworm, Bombyx mori. In order to lower the risk of accidental infection to silkworm we have developed sporeless mutants through chemical mutagenesis of a wild type Btk. An isolate of Btk (HR-Px91) was obtained from cadaver of the cabbage pest, Plutella xylostella. Exponential growth phase cells of Btk were exposed to the mutagen N-methyl-N′-nitro, N-nitrosoguanidine and crystalliferous but sporulation-deficient (Spo? Cry+) mutants were isolated. Five oligosporogenous (OS) mutants were selected based on characteristics like autolysis, insecticidal crystal production and toxicity to larvae of P. xylostella, Crocidolomia binotalis and Helicoverpa armigere. Mutagenesis had not affected the quantity of toxins produced on solid medium by the five OS mutants when compared with the wilcitype HR-Px91. Also there was no significant differences in the toxicity of crystals from two OS mutants and those produced by Btks of wild type and a commercial formulation ‘Bactospeine’. Field studies have unequivocally demonstrated the efficacy of OS mutant HR-Pu7 in protecting cabbage crop against the major insect pests, P. xylostella and C. binotalis. The field efficacy was at-par with ‘Batospeine’ at an equivalent crystal-protein concentration, when evaluated based on marketable yield of cabbage obtained and pest damage. Thus, sporeless mutants of Btk could be generated by chemical mutagenesis and effectively used for plant protection in sericulture tracts with minimum risk to silkworm. 相似文献
114.
115.
Baranabas David Jayaseelan Baskaralingam Vaseeharan Athisuyambulingam Maharajan Sathappan Shanthi Gopalakrishnan Vinoj 《Annals of microbiology》2013,63(4):1601-1609
The in vitro vibriostatic effects of probiotic Bacillus licheniformis strains (Dahb1 to Dahb7) from both wild and commercial sources were evaluated against pathogenic Vibrios isolated from shrimp hatcheries and farms. Agar antagonism assay results showed that, out of seven B. licheniformis strains, strain Dahb1 showed the biggest inhibitory zone (6–12 mm) tested against 162 isolates of Vibrio spp. viz., V. harveyi (53 isolates), V. anguillarum (42 isolates), V. vulnificus (31 isolates) and Photobacterium damselae ssp. damselae (36 isolates) obtained from Penaeus monodon culture hatcheries and ponds. The genetic status of these seven strains were analyzed through randomly amplified polymorphic DNA analysis using 18 random primers. Of the 18 primers studied, only 6 generated repeatable polymorphic DNA bands with sizes ranging from 250 to 1,000 bp in seven isolates of B. licheniformis. The dendrogram generated from resolved gel profiles showed two major branches with three clusters. The results of the present study allow us to conclude that B. licheniformis Dahb1 can be used as an effective probiotic to control Vibrios. Field studies are needed to evaluate probiotic efficiency to control diseases in aquatic organisms. 相似文献
116.
Human population density in the coastal zone and potential impacts of climate change underscore a growing conflict between coastal development and an encroaching shoreline. Rising sea-levels and increased storminess threaten to accelerate coastal erosion, while growing demand for coastal real estate encourages more spending to hold back the sea in spite of the shrinking federal budget for beach nourishment. As climatic drivers and federal policies for beach nourishment change, the evolution of coastline mitigation and property values is uncertain. We develop an empirically grounded, stochastic dynamic model coupling coastal property markets and shoreline evolution, including beach nourishment, and show that a large share of coastal property value reflects capitalized erosion control. The model is parameterized for coastal properties and physical forcing in North Carolina, U.S.A. and we conduct sensitivity analyses using property values spanning a wide range of sandy coastlines along the U.S. East Coast. The model shows that a sudden removal of federal nourishment subsidies, as has been proposed, could trigger a dramatic downward adjustment in coastal real estate, analogous to the bursting of a bubble. We find that the policy-induced inflation of property value grows with increased erosion from sea level rise or increased storminess, but the effect of background erosion is larger due to human behavioral feedbacks. Our results suggest that if nourishment is not a long-run strategy to manage eroding coastlines, a gradual removal is more likely to smooth the transition to more climate-resilient coastal communities. 相似文献
117.
Charles J. Billington Jr Brian Schmidt Ralph S. Marcucio Benedikt Hallgrimsson Rajaram Gopalakrishnan Anna Petryk 《Disease models & mechanisms》2015,8(2):139-146
Holoprosencephaly (HPE) is a developmental anomaly characterized by inadequate or absent midline division of the embryonic forebrain and midline facial defects. It is believed that interactions between genes and the environment play a role in the widely variable penetrance and expressivity of HPE, although direct investigation of such effects has been limited. The goal of this study was to examine whether mice carrying a mutation in a gene encoding the bone morphogenetic protein (BMP) antagonist twisted gastrulation (Twsg1), which is associated with a low penetrance of HPE, are sensitized to retinoic acid (RA) teratogenesis. Pregnant Twsg1+/− dams were treated by gavage with a low dose of all-trans RA (3.75 mg/kg of body weight). Embryos were analyzed between embryonic day (E)9.5 and E11.5 by microscopy and geometric morphometric analysis by micro-computed tomography. P19 embryonal carcinoma cells were used to examine potential mechanisms mediating the combined effects of increased BMP and retinoid signaling. Although only 7% of wild-type embryos exposed to RA showed overt HPE or neural tube defects (NTDs), 100% of Twsg1−/− mutants exposed to RA manifested severe HPE compared to 17% without RA. Remarkably, up to 30% of Twsg1+/− mutants also showed HPE (23%) or NTDs (7%). The majority of shape variation among Twsg1+/− mutants was associated with narrowing of the midface. In P19 cells, RA induced the expression of Bmp2, acted in concert with BMP2 to increase p53 expression, caspase activation and oxidative stress. This study provides direct evidence for modifying effects of the environment in a genetic mouse model carrying a predisposing mutation for HPE in the Twsg1 gene. Further study of the mechanisms underlying these gene-environment interactions in vivo will contribute to better understanding of the pathogenesis of birth defects and present an opportunity to explore potential preventive interventions.KEY WORDS: Twisted gastrulation, Twsg1, Bone morphogenetic protein, Holoprosencephaly, Retinoic acid, Apoptosis, Oxidative stress 相似文献
118.
Andrew R. H. Dalton Eszter P. Vamos Matthew J. Harris Gopalakrishnan Netuveli Robert M. Wachter Azeem Majeed Christopher Millett 《PloS one》2014,9(1)
Background
The Patient Protection and Affordable Care Act (ACA) galvanised debate in the United States (US) over universal health coverage. Comparison with countries providing universal coverage may illustrate whether the ACA can improve health outcomes and reduce disparities. We aimed to compare quality and disparities in hypertension management by socio-economic position in the US and England, the latter of which has universal health care.Method
We used data from the Health and Retirement Survey in the US, and the English Longitudinal Study for Aging from England, including non-Hispanic White respondents aged 50–64 years (US market-based v NHS) and >65 years (US-Medicare v NHS) with diagnosed hypertension. We compared blood pressure control to clinical guideline (140/90 mmHg) and audit (150/90 mmHg) targets; mean systolic and diastolic blood pressure and antihypertensive prescribing, and disparities in each by educational attainment, income and wealth, using regression models.Results
There were no significant differences in aggregate achievement of clinical targets aged 50 to 65 years (US market-based vs. NHS- 62.3% vs. 61.3% [p = 0.835]). There was, however, greater control in the US in patients aged 65 years and over (US Medicare vs. NHS- 53.5% vs. 58.2% [p = 0.043]). England had no significant socioeconomic disparity in blood pressure control (60.9% vs. 63.5% [p = 0.588], high and low wealth aged ≥65 years). The US had socioeconomic differences in the 50–64 years group (71.7% vs. 55.2% [p = 0.003], high and low wealth); these were attenuated but not abolished in Medicare beneficiaries.Conclusion
Moves towards universal health coverage in the US may reduce disparities in hypertension management. The current situation, providing universal coverage for residents aged 65 years and over, may not be sufficient for equality in care. 相似文献119.
M. Gopalakrishnan J. Thanusu V. Kanagarajan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):669-675
Some 2,6-diarylpiperidin/tetrahydrothiopyran/tetrahydropyran-4-one oximes were synthesized in dry media under microwave irradiation and were evaluated for their in vitro antibacterial activity against clinically isolated bacterial strains i.e. S.aureus, β-H.Streptococcus, E.coli, P.aeruginosa, S.typhii and in vitro antifungal activities against fungal strains i.e. C.albicans, Rhizopus, A.niger and A.flavus. Structure-activity relationships for the synthesized compounds showed that compounds 12 and 15 exerted excellent antibacterial activity against all the tested bacterial strains except 15 against S.aureus and β-H.streptococcus. Against C.albicans and A.flavus, compound 15 exerted potent antifungal activities while against Rhizopus, compound 16 showed promising activity. 相似文献
120.
Lakra WS Goswami M Yadav K Gopalakrishnan A Patiyal RS Singh M 《In vitro cellular & developmental biology. Animal》2011,47(2):89-94
The Puntius denisonii colloquially and more popularly referred to as Miss Kerala is a subtropical fish belonging to the genus Puntius (Barb) and family Cyprinidae. Two cell lines PDF and PDH were developed from the caudal fin and heart of P. denisonii, respectively. The cell lines were optimally maintained at 26°C in Leibovitz-15 medium supplemented with 10% fetal bovine serum. A diploid count of 50 chromosomes at passage 50 was observed in both the cell lines. The high growth potential of the cell lines was reflected from the cell doubling time of 28 and 30?h of PDF and PDH cell lines, respectively. The viability of the PDF and PDH cell lines was 70% and 76%, respectively, after 4?mo of storage in liquid nitrogen (-196°C). The origin of the cell lines was confirmed by the amplification of 653?bp fragments of cytochrome oxidase subunit I of mitochondrial DNA genes. 相似文献