150 research outputs found
Evaluation of chemical compounds for induction of male sterility in wheat (Triticum aestivum L.)
The short-list of eleven chemical hybridizing agents (CHAs) showing 98% or more induction of male sterility
were identified following application at the pre-meiotic stage of wheat. Among ethyl oxanilates, 4-fluoro (CHA
A1), 4-bromo (CHA A2), 4-trifluoromethyl (CHA A5), and 4-cyano (CHA A3) derivatives; and among pyridones,
4-chloro (CHA B3), 4-fluoro (CHA B1), 4-bromo (CHA B2), and 4-trifluoromethyl (CHA B6) derivatives were
the most promising. These agents showed no adverse effects on plant growth and yield. Ethyl 4-fluoro oxanilate
(CHA A1) was tested on 29 wheat genotypes at 1500 ppm and induced 99.76┬▒0.37% male sterility. Ethyl 4-fluoro
oxanilate residues were non-detectable in grain and husk and thus appeared to have no lasting residue effects
Ethyloxanilates as specific male gametocides for wheat (Triticum aestivum L.)
Induction of male sterility by deployment of male gametocides holds
immense potential in heterosis breeding of wheat. The efficacy of a new
class of male gametocide for wheat (Triticum aestivum L.) is described:
ethyloxanilates, the most active example of this class being ethyl
4-fluorooxanilate (E4FO). E4FO induces male sterility, specifically,
without detectable effects on various agronomic features and female
fertility. The plants sprayed once with 0.15% E4FO exhibited 100%
pollen and floret sterility without causing a significant reduction in
total yield. E4FO was screened on 29 genotypes of wheat at 0.15% test
concentration and was observed to induce 99.76 ┬▒ 0.37% male
sterility. Thirteen F1-hybrids of wheat were produced using the
gametocide in Winter 2000тАУ2001 and were evaluated for their
agronomic performance in Winter 2001тАУ2002. The cross combinations
viz., lines WR 544 ┬╖ HW 2046 and HW 2044 ┬╖ WR 956 have
outperformed their respective better parents by 48.17% and 23.42%
in grain yield/plant and thus have potential as hybrids
Synthesis and Screening of Anilides Having Olefinic and Alkyl Moiety in the Side Chain as Chemical Hybridizing Agents for Wheat ( Triticum aestivum L.)
Induction of male sterility by deployment of chemical hybridizing agents (CHAs) holds immense
potential in heterosis breeding of wheat. A total of 21 anilides having different aromatic substitutions
and side-chain variation were synthesized and screened as CHAs on three genotypes of wheat viz.,
PBW 343, HW 2046, and HD 2733, at winter season. Various anilides having vinyl moiety in the acyl
side chain were synthesized by condensation between substituted anilines with different esters or
acid chlorides. Another lead in the form of N-alkyl anilines also became evident. The percent male
sterility data caused by CHAs revealed the significant contribution of anilides containing vinyl double
bond incorporated in the form of closed ring structure viz., furyl moiety as the side chain. 4┬в-Fluorofuryl
anilide (1) and 4┬в-bromo-furyl anilide (2) are found to be promising lead CHAs for the design of
highly active molecules. QSAR analysis revealed a direct relationship of field effect exemplified by
the Swain-Lupton constant Fp for the aromatic substitution but an inverse relationship of molar
refractivity MR for the side chain. The negative influences of parachor for the acyl domain have been
underlined. The real guiding principle for selectivity of CHA action was found to be the ├░ value. The
CHAs act by mimicking UDP-glucose, the key substrate in the synthesis of callose, or lead to an
imbalance in acid-base equilibrium in pollen mother cells resulting in dissolution of callose wall by
premature callase secretion
Eicosapentaenoic Acid Enrichment from Sardine Oil by Argentation Chromatography
Eicosapentaenoic acid (EPA) derived from chemically hydrolyzed sardine oil was concentrated by
urea fractionation using methanol at different temperatures (2, 4, and 6 ┬░C) and urea/fatty acid ratios
(2:1, 3:1, and 4:1 w/w) and purified by argentation neutral alumina column chromatography. The
individual fatty acids were determined as fatty acid methyl esters (FAME) by gas-liquid chromatography
and gas chromatography-mass spectroscopy as FAME and N-acyl pyrrolidides. In the mass
fragmentation pattern of FAME, the base peak was assigned to be the 1-methoxyethenol moiety
(m/ z) 74) obtained by McLafferty rearrangement. Formation of the cyclic tropylium ion (m/ z) 91)
in fatty acids with four or more double bonds was apparent in FAME-PUFAs. The base peak of
N-acyl pyrrolidides was the McLafferty rearrangement ion, 1-(pyrrolidin-1-yl)ethenol (m/ z) 113). The
highest concentration of EPA (47.78%) was obtained at the crystallization temperature of 4 ┬░C with
a urea/fatty acid ratio of 4:1 (w/w) with 93.74% yield. After complexation of saturated and less
unsaturated fatty acids by urea complexation, argentation chromatography resulted in an EPA of
high purity (99.6%) with an overall recovery of 54.09% using 50% diethyl ether/ n-hexane as eluting
solvent. The peroxide (POV) and thiobarbituric acid (TBS) values were found to be highest (4.0 mequiv
of O2/kg and 5.2 mg of malondialdehyde/kg, respectively) during urea fractionation at the higher
crystallization temperature (6 ┬░C) and higher urea/fatty acid ratio (4:1)
Synthesis and Characterization of N-Acylaniline Derivatives as Potential Chemical Hybridizing Agents (CHAs) for Wheat ( Triticum aestivum L.)
Induction of male sterility by deployment of chemical hybridizing agents (CHAs) are important in
heterosis breeding of self-pollinated crops like wheat, wherein the male and female organs are in the
same flower. Taking a lead from the earlier work on rice, a total of 25 N-acylanilines comprising of
malonanilates, acetoacetanilides, and acetanilides (including halogenated acetanilides) were synthesized
and screened as CHAs on three genotypes of wheat, viz., PBW 343, HD 2046, and HD
2733 at 1500 ppm in the winter of 2001-2002. The N-acylanilines containing variations at the acyl
and aromatic domain were synthesized by condensation of substituted anilines with appropriate
diesters, acid chlorides, or monoesters. The test compounds with highly electronegative groups such
as F/Br at the paraposition of the aryl ring were identified as the most potent CHAs, causing higher
induction of male sterility. A variation of N-substitution at the side chain generally furnished analogues
like 4┬в-fluoroacetoacetanilide (7) and ethyl 4┬в-fluoromalonanilate (1), which induced 89.12 and 84.66%
male sterility, respectively, in PBW 343. Among halogenated acetanilides, the increasing number of
chlorine atoms in the side chain led to an increase in the activity of 4┬в-fluoro (23) and 4┬в-bromo (24)
derivatives of trichoroacetanilides, which induced >87% male sterility. Quantitative structure-activity
relationship (QSAR) models indicated the positive contributions of the field effect exemplified by the
Swain-Lupton constant ( Fp) and negative contributions of the Swain-Lupton resonance constant
( R) for the aromatic substitution. The positive influences of parachor ( P) for the acyl domain have
been underlined. These leads will be significant in explaining the CHA fit in the macromolecular
receptor site. The CHAs appeared to act by causing an imbalance in the acid-base equilibrium in
pollen mother cells resulting in dissolution of the callose wall by premature callase secretion
Quantitative Structure-Activity Relationship Analysis as a Tool To Evaluate the Mode of Action of Chemical Hybridizing Agents for Wheat ( Triticum aestivum L.)
Augmentation of wheat production calls for introduction of wheat hybrids in cultivation. In the absence
of viable alternative technology of hybrid wheat development, chemical induction of male sterility
mediated technology based on chemical hybridizing agents (CHAs) holds a great potential. The QSAR
method was applied to two families of CHAs in the N-acylanilines and pyridone class of chemistry.
The models for each CHA family gave good correlation between the variations in log percent of male
sterility and the steric-electrostatic properties of the sets. QSAR analysis has revealed a direct
relationship of the Swain-Lupton constant Fp and molecular mass but an inverse relationship of
MR, ES, and Swain-Lupton resonance constant Rin influencing the bioactivity in the N-acylanilines.
QSAR analysis of four parent families consisting of two training sets each of pyrid-2-ones and prid-
4-ones revealed the positive contributions of field effect exemplified by the Swain-Lupton field constant
( F) and the negative contributions of the molar refractivity (MR) of aromatic substituents in all but
one training set. The QSAR models also indicated that increased steric bulk at the 4-position on the
phenyl ring is associated with enhanced activity. These leads will be useful in explaining the CHA
binding fit in the macromolecular receptor site
Maternal antenatal multiple micronutrient supplementation for long-term health benefits in children: a systematic review and meta-analysis
BACKGROUND: Multiple micronutrient supplementation for pregnant women reduces low birth weight and has been recommended in low- and middle-income countries (LMICs) to improve child survival, growth and health. We aimed to review the evidence from long-term follow-up studies of multiple micronutrient supplementation beginning in the later first or second trimester. METHODS: We searched systematically for follow-up reports from all trials in a 2015 Cochrane review of multiple micronutrient supplementation in pregnancy. The intervention comprised three or more micronutrients and the comparison group received iron (60┬аmg) and folic acid (400┬а╬╝g), where possible. Median gestation of commencement varied from 9 to 23┬аweeks. Primary outcomes were offspring mortality, height, weight and head circumference, presented as unadjusted differences in means or proportions (intervention minus control). Secondary outcomes included other anthropometry, body composition, blood pressure, and cognitive and lung function. RESULTS: We found 20 follow-up reports from nine trials (including 88,057 women recruited), six of which used the UNIMMAP supplement designed to provide recommended daily allowances. The age of follow-up ranged from 0 to 9┬аyears. Data for mortality estimates were available from all trials. Meta-analysis showed no difference in mortality (risk difference -0.05 per 1000 livebirths; 95┬а% CI, -5.25 to 5.15). Six trials investigated anthropometry and found no difference at follow-up in weight-for-age z score (0.02; 95┬а% CI, -0.03 to 0.07), height-for-age z score (0.01; 95┬а% CI, -0.04 to 0.06), or head circumference (0.11┬аcm; 95┬а% CI, -0.03 to 0.26). No differences were seen in body composition, blood pressure, or respiratory outcomes. No consistent differences were seen in cognitive function scores. CONCLUSIONS: There is currently no evidence that, compared with iron and folic acid supplementation, routine maternal antenatal multiple micronutrient supplementation improves childhood survival, growth, body composition, blood pressure, respiratory or cognitive outcomes
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The political views of doctors in the United Kingdom: A cross sectional study
Background: Little is known about the political views of doctors in the United Kingdom, despite their importance in the functioning of the National Health Service.
Methods: Survey-based cross-sectional study in which we asked questions about voting behaviour in 2015 and 2017 UK general elections and 2016 referendum on leaving the European Union (Brexit) and questions relating to recent health policies.
Results: 1,172 doctors (45.1% women) from 1,295 responded to an online survey. 60.5% described their political views as тАШleft-wingтАЩ and 62.2% described themselves as тАШliberalтАЩ. 79.4% of respondents voted to remain in the EU in the 2016 referendum compared to 48.1% of voters as a whole (╧З2=819.8, p<0.001). 98.6% of respondents agreed that EU nationals working in the NHS should be able to remain in the UK after Brexit. The median score for the impact of Brexit on the NHS on a scale of 0 (worst impact) to 10 (best impact) was 2 (IQR=1-4). Most respondents agreed with the introduction of minimum alcohol pricing in the UK (73.9%), charging patients who are not eligible for NHS treatment for non-urgent care (70.6%) and protecting a portion of national spending for the NHS (87.1%). 65.8% thought there was too much use of NHS-funded private sector provision in their medical practice. Specialty, income and grade were associated with divergent opinions.
Conclusions: UK doctors are left-leaning and liberal in general, which is reflected in their opinions on topical health policy issues. Doctors in the UK voted differently from the general electorate in recent polls
Improving health-care quality in resource-poor settings
Improvements in health-care quality can contribute to healthier populations. However, many global and national health strategies are not sufficiently considering the issues of measuring and improving health-care quality in low-resource settings.1 The barriers to delivering high-quality care are often similar across different health systems. However, the extent and mechanisms through which these barriers affect quality improvement interventions may be different in resource-poor settings.2 Investments in health systems strengthening without continuous quality improvement is thought to be a useless effort.3 Conversely, only focusing on quality improvement in a resource-poor context without engaging the broader health system for support is of limited value. Hence, both areas must be improved simultaneously
Racism, xenophobia, and discrimination: mapping pathways to health outcomes
Despite being globally pervasive, racism, xenophobia, and discrimination are not universally recognised determinants of health. We challenge widespread beliefs related to the inevitability of increased mortality and morbidity associated with particular ethnicities and minoritised groups. In refuting that racial categories have a genetic basis and acknowledging that socioeconomic factors offer incomplete explanations in understanding these health disparities, we examine the pathways by which discrimination based on caste, ethnicity, Indigeneity, migratory status, race, religion, and skin colour affect health. Discrimination based on these categories, although having many unique historical and cultural contexts, operates in the same way, with overlapping pathways and health effects. We synthesise how such discrimination affects health systems, spatial determination, and communities, and how these processes manifest at the individual level, across the life course, and intergenerationally. We explore how individuals respond to and internalise these complex mechanisms psychologically, behaviourally, and physiologically. The evidence shows that racism, xenophobia, and discrimination affect a range of health outcomes across all ages around the world, and remain embedded within the universal challenges we face, from COVID-19 to the climate emergency
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