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排序方式: 共有176条查询结果,搜索用时 15 毫秒
101.
Jonatan Niño‐Sánchez Prabhakaran T. Sambasivam Anne Sawyer Rachael Hamby Angela Chen Elizabeth Czislowski Peng Li Narelle Manzie Donald M. Gardiner Rebecca Ford Zhi Ping Xu Neena Mitter Hailing Jin 《植物学报(英文版)》2022,64(11):2187-2198
One of the most promising tools for the control of fungal plant diseases is spray-induced gene silencing (SIGS). In SIGS, small interfering RNA (siRNA) or double-stranded RNA (dsRNA) targeting essential or virulence-related pathogen genes are exogenously applied to plants and postharvest products to trigger RNA interference (RNAi) of the targeted genes, inhibiting fungal growth and disease. However, SIGS is limited by the unstable nature of RNA under environmental conditions. The use of layered double hydroxide or clay particles as carriers to deliver biologically active dsRNA, a formulation termed BioClay™, can enhance RNA durability on plants, prolonging its activity against pathogens. Here, we demonstrate that dsRNA delivered as BioClay can prolong protection against Botrytis cinerea, a major plant fungal pathogen, on tomato leaves and fruit and on mature chickpea plants. BioClay increased the protection window from 1 to 3 weeks on tomato leaves and from 5 to 10 days on tomato fruits, when compared with naked dsRNA. In flowering chickpea plants, BioClay provided prolonged protection for up to 4 weeks, covering the critical period of poding, whereas naked dsRNA provided limited protection. This research represents a major step forward for the adoption of SIGS as an eco-friendly alternative to traditional fungicides. 相似文献
102.
Núbia Boechat Alcione S Carvalho Kelly Salom?o Solange L de Castro Carlos F Araujo-Lima Francisco VC Mello Israel Felzenszwalb Claudia AF Aiub Taline Ramos Conde Helena PS Zamith Rolf Skupin Günter Haufe 《Memórias do Instituto Oswaldo Cruz》2015,110(4):492-499
Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and
cytotoxic properties have been attributed to the presence of the nitro group.
However, we synthesised nitroimidazoles with activity against the trypomastigotes of
Trypanosoma cruzi, but that were not genotoxic. Herein,
nitroimidazoles (11-19) bearing different substituent groups were investigated for
their potential induction of genotoxicity (comet assay) and mutagenicity
(Salmonella/Microsome assay) and the correlations of these
effects with their trypanocidal effect and with megazol were investigated. The
compounds were designed to analyse the role played by the position of the nitro group
in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable
groups at N-1 as an anion receptor group and the role of a methyl group at C-2.
Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to
those bearing NO2 at C-5. However, when there was a CH3
at C-2, the position of the NO2 group had no influence on the genotoxic activity.
Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3
at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl)
and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on
genotoxicity. This study contributes to the future search for new and safer
prototypes and provide. 相似文献
103.
Sullivan R Kinra S Ekelund U Bharathi AV Vaz M Kurpad A Collier T Reddy KS Prabhakaran D Ben-Shlomo Y Davey Smith G Ebrahim S Kuper H 《PloS one》2011,6(10):e24898
Objective
To investigate the relationship between rural to urban migration and physical activity (PA) in India.Methods
6,447 (42% women) participants comprising 2077 rural, 2,094 migrants and 2,276 urban were recruited. Total activity (MET hr/day), activity intensity (min/day), PA Level (PAL) television viewing and sleeping (min/day) were estimated and associations with migrant status examined, adjusting for the sib-pair design, age, site, occupation, education, and socio-economic position (SEP).Results
Total activity was highest in rural men whereas migrant and urban men had broadly similar activity levels (p<0.001). Women showed similar patterns, but slightly lower levels of total activity. Sedentary behaviour and television viewing were lower in rural residents and similar in migrant and urban groups. Sleep duration was highest in the rural group and lowest in urban non-migrants. Migrant men had considerably lower odds of being in the highest quartile of total activity than rural men, a finding that persisted after adjustment for age, SEP and education (OR 0.53, 95% CI 0.37, 0.74). For women, odds ratios attenuated and associations were removed after adjusting for age, SEP and education.Conclusion
Our findings suggest that migrants have already acquired PA levels that closely resemble long-term urban residents. Effective public health interventions to increase PA are needed. 相似文献104.
Huffman MD Rao KD Pichon-Riviere A Zhao D Harikrishnan S Ramaiya K Ajay VS Goenka S Calcagno JI Caporale JE Niu S Li Y Liu J Thankappan KR Daivadanam M van Esch J Murphy A Moran AE Gaziano TA Suhrcke M Reddy KS Leeder S Prabhakaran D 《PloS one》2011,6(6):e20821
Objective
To estimate individual and household economic impact of cardiovascular disease (CVD) in selected low- and middle-income countries (LMIC).Background
Empirical evidence on the microeconomic consequences of CVD in LMIC is scarce.Methods and Findings
We surveyed 1,657 recently hospitalized CVD patients (66% male; mean age 55.8 years) from Argentina, China, India, and Tanzania to evaluate the microeconomic and functional/productivity impact of CVD hospitalization. Respondents were stratified into three income groups. Median out-of-pocket expenditures for CVD treatment over 15 month follow-up ranged from 354 international dollars (2007 INT$, Tanzania, low-income) to INT$2,917 (India, high-income). Catastrophic health spending (CHS) was present in >50% of respondents in China, India, and Tanzania. Distress financing (DF) and lost income were more common in low-income respondents. After adjustment, lack of health insurance was associated with CHS in Argentina (OR 4.73 [2.56, 8.76], India (OR 3.93 [2.23, 6.90], and Tanzania (OR 3.68 [1.86, 7.26] with a marginal association in China (OR 2.05 [0.82, 5.11]). These economic effects were accompanied by substantial decreases in individual functional health and productivity.Conclusions
Individuals in selected LMIC bear significant financial burdens following CVD hospitalization, yet with substantial variation across and within countries. Lack of insurance may drive much of the financial stress of CVD in LMIC patients and their families. 相似文献105.
Mendenhall E Narayanan G Prabhakaran D 《Diabetic medicine : a journal of the British Diabetic Association》2012,29(9):e308-e311
Diabet. Med. 29, e308-e311 (2012) ABSTRACT: As diabetes prevalence shifts from affluent to lower-income groups in India, focus on depression in diabetes will become essential. This paper describes four perspectives through which depression and diabetes should be understood in the Indian context. We consider (1) how rapid socio-economic and demographic changes contribute to increased co-occurring diabetes and depression; (2) how social, cultural and economic factors in the Indian context contribute to depression and therefore play an important role in diabetes care; (3) biological and behavioural pathways between depression and diabetes; and (4) the role of health systems in depression, diabetes and their overlap. We conclude with recommendations for future research and policy on this topic in India. 相似文献
106.
Premalata CS Gayathri Devi M Biswas S Mukherjee G Balu S Sundareshan TS Prabhakaran PS 《Acta cytologica》2003,47(3):475-479
BACKGROUND: Primitive neurocetodermal tumors (PNETs) constitute a family of neoplasms of presumed neuroectrodermal origin most often presenting as bone or soft tissue masses. There are very few reported cases of PNET of the kidney and none diagnosed by fine needle aspiration cytology (FNAC), to the best of our knowledge, in the world literature. We present two cases of renal PNET diagnosed on cytology. CASES: Two patients with renal masses were diagnosed as having PNET on FNAC. Cytologically the tumors showed a dispersed population of malignant small round cells with focal rosette formation and perivascular arrangement of tumor cells. Immunohistochemistry on the cell blocks in both cases showed strong membrane positivity for CD99 (MIC2). Cytogenetic studies in both cases showed the characteristic t(11;22)(q24;q12) translocation, with additional chromosomal abnormalities in case 2. CONCLUSION: PNET of the kidney is a distinct entity and can be diagnosed on fine needle aspiration smears and confirmed with immunohistochemistry and cytogenetic studies. A diagnosis of PNET must be included in the differential diagnosis of renal masses in adolescents and young adults. 相似文献
107.
Pace CN Treviño S Prabhakaran E Scholtz JM 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2004,359(1448):1225-34; discussion 1234-5
Proteins carry out the most difficult tasks in living cells. They do so by interacting specifically with other molecules. This requires that they fold to a unique, globular conformation that is only marginally more stable than the large ensemble of unfolded states. The folded state is stabilized mainly by the burial and tight packing of over 80% of the peptide groups and non-polar side chains. If life as we know it is to exist in a solvent other than water, the folded state must be stable and soluble in the new solvent. Our analysis suggests that proteins will be unstable in most polar solvents such as ethanol, extremely stable in non-polar solvents such as cyclohexane, and even more stable in a vacuum. Our solubility studies suggest that protein solubility will be markedly lower in polar solvents such as ethanol and that proteins will be essentially insoluble in non-polar solvents such as cyclohexane. For these and other reasons it seems unlikely that the life we know could exist in any solvent system other than water. 相似文献
108.
Rao MJ Malavalli A Manjula BN Kumar R Prabhakaran M Sun DP Ho NT Ho C Nagel RL Acharya AS 《Journal of molecular biology》2000,300(5):1389-1406
Interspecies hybrid HbS (alpha(2)(P)beta(2)(S)), has been assembled in vitro from pig alpha-globin and human beta(S)-chain. The alpha(2)(P)beta(2)(S) retains normal tetrameric structure (alpha(2)beta(2)) of human Hb and an O(2) affinity comparable to that of HbS in 50 mM Hepes buffer; but, its O(2) affinity is slightly higher than that of HbS in the presence of allosteric effectors (chloride, DPG and phosphate). The (1)H-NMR spectroscopy detected distinct differences between the heme environments and alpha(1)beta(1) interfaces of pig Hb and HbS, while their alpha(1)beta(2) interfaces appear very similar. The interspecies hybrid alpha(2)(H)beta(2)(P) resembles pig Hb; the pig beta-chain dictated the conformation of the heme environment of the human alpha-subunit, and to the alpha(1)beta(1) interfaces of the hybrid. In the alpha(2)(P)beta(2)(S) hybrid, beta(S)-chain dictated the conformation of human heme environment to the pig alpha-chain in the hybrid; but the conformation of alpha(1)beta(1) interface of this hybrid is close to, but not identical to that of HbS. On the other hand, the alpha(1)beta(2) interface conformation is identical to that of HbS. More important, the alpha(2)(P)beta(2)(S) does not polymerize when deoxygenated; pig alpha-chain completely neutralizes the beta(S)-chain dependent polymerization. The polymerization inhibitory propensity of pig alpha-chain is higher when it is present in the cis alpha(P)beta(S) dimer relative to that in a trans alpha(P)beta(A) dimer. The semisynthetically generated chimeric pig-human and human-pig alpha-chains by exchanging the alpha(1-30) segments of human and pig alpha-chains have established that the sequence differences of pig alpha(31-141) segment can also completely neutralize the polymerization. Comparison of the electrostatic potential energy landscape of the alpha-chain surfaces of HbS and alpha(2)(P)beta(2)(S) suggests that the differences in electrostatic potential energy surfaces on the alpha-chain of alpha(2)(P)beta(2)(S) relative to that in HbS, particularly the ones involving CD region, E-helix and EF-corner of pig alpha-chain are responsible for the polymerization neutralization activity. The pig and human-pig chimeric alpha-chains can serve as blueprints for the design of a new generation of variants of alpha-chain(s) suitable for the gene therapy of sickle cell disease. 相似文献
109.
Tan Robert K. -Z.; Prabhakaran M.; Tung Chang-Shung; Harvey Stephen C. 《Bioinformatics (Oxford, England)》1988,4(1):147-151
A UGUR is a program to predict, display and analyze the three-dimensionalstructure of B-DNA. The user can choose one of six models topredict the helical parameters of a given sequence. These parametersare then used to generate the coordinates of the DNA model inthree-dimensional space (trajectory). The trajectory can bedisplayed and rotated on a graphics terminal The trajectoryand helical parameters can also be searched for bends and structuralhomologues.
Received on August 17, 1987; accepted on December 31, 1987 相似文献
110.
Algae flocculation in reservoir water 总被引:1,自引:0,他引:1
Removal of algae in the reservoir water was studied by electroflocculation using a bipolar cell with aluminum electrodes and flocculation by treatment with commercial alum. Comparison of both the methods is discussed. 相似文献