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1.
Health Sci Rep ; 5(4): e741, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35873404

RESUMO

Background and Aim: In Ayurveda, ashwagandha is a popular plant for promoting youthful energy, longevity, and overall well-being. It is also an excellent aphrodisiac herb that aids in the improvement and maintenance of normal sexual health. The present study aims to evaluate the effect of ashwagandha root extract on improving sexual health in adult males. Methods: In this 8-week randomized, double-blind, placebo-controlled study, we investigated the aphrodisiac property of an ashwagandha root extract in adult males. Fifty participants with lower sexual desire were randomly allocated to take 300 mg of ashwagandha root extract or placebo capsules twice daily. Outcomes were measured using the derogatis interview for sexual functioning-male (DISF-M) questionnaire, serum testosterone, serum prolactin, and short-form survey-36 quality of life questionnaire before and after the intervention. Results: Compared to placebo, ashwagandha root extract supplementation was associated with a statistically significant increase in the total DISF-M scores (mean difference -9.8; 95% confidence interval, -10.73 to -8.87; p < 0.0001; t-test). It was also associated with a statistically significant increase in serum testosterone levels (-66.52; -80.70 to -52.34; p < 0.0001; t-test). However, the prolactin level did not change after intervention in both the ashwagandha and placebo groups (-1.06; -2.78 to 0.66; p > 0.05). Conclusion: These findings suggest that ashwagandha demonstrated a significant subjective perception of sexual well-being and assisted in increasing serum testosterone levels in the participants.

2.
Pure Appl Geophys ; 179(4): 1403-1419, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250099

RESUMO

The association between aerosol and lightning has been investigated with long-term decadal data (2005-2014) for lightning, aerosol optical depth (AOD), relative humidity, and effective cloud droplet size. To understand the complex relationship between aerosol and lightning, two different regions with different climatic and weather conditions, a humid region R1 (22°-29° N, 89°-92° E) and an arid region R2 (23°-28° N, 70°-76° E) of northern India, were chosen for the study domain. The results show that lightning activity was observed to occur more over the humid region R1, i.e., 1141 days (1/3 of total days), than over the arid region R2, i.e., 740 days (1/5 of total days). Also, over the humid region R1, the highest lightning flash density was recorded as nearly 4.6 × 10-4 flashes/km2/day observed for 18 days (1.5%); on the contrary, over the arid region R2, the maximum lightning flash density was observed to be 2.5 × 10-4 flashes/km2/day and occurred for about 22 days (2.9%). The analysis shows that a nonlinear relationship exists between aerosol and lightning with a highly associated influence of relative humidity. A very significant positive and negative co-relation that varies with relative humidity has been observed between AOD and lightning for both humid and arid regions. This shows relative humidity is the key factor in determining the increase or decrease of lightning activity. This study also shows that the larger the cloud droplet size, the higher the relative humidity and vice versa. This study emphasizes that aerosol concentration in the atmosphere influences cloud microphysics by modulating the size of cloud droplets and thereby regulating the lightning frequency. The atmospheric humidity is the driving factor in deciding the positive or negative co-relationship between aerosol and lightning. Supplementary Information: The online version contains supplementary material available at 10.1007/s00024-022-02981-6.

3.
Front Plant Sci ; 10: 724, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214233

RESUMO

Apomixis (asexual seed formation) in angiosperms occurs either sporophytically, through adventitious embryony, or gametophytically, where an unreduced female gametophyte (embryo sac) forms and produces an unreduced egg that develops into an embryo parthenogenetically. Multiple types of gametophytic apomixis occur, and these are differentiated based on where and when the unreduced gametophyte forms, a process referred to as apomeiosis. Apomeiotic gametophytes form directly from ameiotic megasporocytes, as in Antennaria-type diplospory, from unreduced spores derived from 1st division meiotic restitutions, as in Taraxacum-type diplospory, or from cells of the ovule wall, as in Hieracium-type apospory. Multiple types of apomeiosis occasionally occur in the same plant, which suggests that the different types occur in response to temporal and/or spatial shifts in termination of sexual processes and onset timing of apomeiosis processes. To better understand the origins and evolutionary implications of apomixis in Boechera (Brassicaceae), we determined apomeiosis type for 64 accessions representing 44 taxonomic units. Plants expressing apospory and diplospory were equally common, and these generally produced reduced and unreduced pollen, respectively. Apospory and diplospory occurred simultaneously in individual plants of seven taxa. In Boechera, apomixis perpetuates otherwise sterile or semisterile interspecific hybrids (allodiploids) through multiple generations. Accordingly, ample time, in these multigenerational clones, is available for rare meioses to produce haploid, intergenomically recombined male and female gametes. The fusion of such gametes could then produce segmentally autoploidized progeny. If sex re-emerges among such progeny, then new and genomically unique sexual species could evolve. Herein, we present evidence that such apomixis-facilitated speciation is occurring in Boechera, and we hypothesize that it might also be occurring in facultatively apomictic allodiploids of other angiospermous taxa.

4.
Front Plant Sci ; 10: 256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30906306

RESUMO

Apomixis is a method of reproduction to generate clonal seeds and offers tremendous potential to fix heterozygosity and hybrid vigor. The process of apomictic seed development is complex and comprises three distinct components, viz., apomeiosis (leading to formation of unreduced egg cell), parthenogenesis (development of embryo without fertilization) and functional endosperm development. Recently, in many crops, these three components are reported to be uncoupled leading to their partitioning. This review provides insight into the recent status of our understanding surrounding partitioning apomixis components in gametophytic apomictic plants and research avenues that it offers to help understand the biology of apomixis. Possible consequences leading to diversity in seed developmental pathways, resources to understand apomixis, inheritance and identification of candidate gene(s) for partitioned components, as well as contribution towards creation of variability are all discussed. The potential of Panicum maximum, an aposporous crop, is also discussed as a model crop to study partitioning principle and effects. Modifications in cytogenetic status, as well as endosperm imprinting effects arising due to partitioning effects, opens up new opportunities to understand and utilize apomixis components, especially towards synthesizing apomixis in crops.

5.
J Exp Bot ; 68(13): 3405-3417, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28633298

RESUMO

Tension wood (TW) is a specialized tissue with contractile properties that is formed by the vascular cambium in response to gravitational stimuli. We quantitatively analysed the proteomes of Populus tremula cambium and its xylem cell derivatives in stems forming normal wood (NW) and TW to reveal the mechanisms underlying TW formation. Phloem-, cambium-, and wood-forming tissues were sampled by tangential cryosectioning and pooled into nine independent samples. The proteomes of TW and NW samples were similar in the phloem and cambium samples, but diverged early during xylogenesis, demonstrating that reprogramming is an integral part of TW formation. For example, 14-3-3, reactive oxygen species, ribosomal and ATPase complex proteins were found to be up-regulated at early stages of xylem differentiation during TW formation. At later stages of xylem differentiation, proteins involved in the biosynthesis of cellulose and enzymes involved in the biosynthesis of rhamnogalacturonan-I, rhamnogalacturonan-II, arabinogalactan-II and fasciclin-like arabinogalactan proteins were up-regulated in TW. Surprisingly, two isoforms of exostosin family proteins with putative xylan xylosyl transferase function and several lignin biosynthesis proteins were also up-regulated, even though xylan and lignin are known to be less abundant in TW than in NW. These data provided new insight into the processes behind TW formation.


Assuntos
Proteínas de Plantas/metabolismo , Populus/metabolismo , Proteoma , Câmbio/crescimento & desenvolvimento , Câmbio/metabolismo , Populus/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento , Madeira/metabolismo , Xilema/crescimento & desenvolvimento , Xilema/metabolismo
6.
Bull Environ Contam Toxicol ; 95(5): 661-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26438175

RESUMO

This paper presents the variation of elemental concentrations of total carbon (TC), total nitrogen (TN) and isotopic ratios of δ13C and δ15N along with δ13OC and OC of PM10 mass over Delhi, Varanasi and Kolkata of the Indo Gangetic Plain (IGP), India. For Delhi, the average concentrations of TC and TN of PM10 were 53.0±33.6 and 14.9±10.8 µg m(-3), whereas δ13C and δ15N of PM10 were -25.5±0.5 and 9.6±2.8‰, respectively. For Varanasi, the average values of δ13C and δ15N of PM10 were -25.4±0.8 and 6.8±2.4‰, respectively. For Kolkata, TC and TN values for PM10 ranged from 9.1-98.2 to 1.4-25.9 µg m(-3), respectively with average values of 32.6±24.9 and 9.3±8.2 µg m(-3), respectively. The average concentrations of δ13C and δ15N were -26.0±0.4 and 7.4±2.7‰, respectively over Kolkata with ranges of -26.6 to -24.9‰ and 2.8±11.5‰, respectively. The isotopic analysis revealed that biomass burning, vehicular emission and secondary inorganic aerosols were likely sources of PM10 mass over IGP, India.


Assuntos
Poluentes Atmosféricos/análise , Isótopos de Carbono/análise , Monitoramento Ambiental/métodos , Isótopos de Nitrogênio/análise , Material Particulado/análise , Aerossóis/análise , Índia , Tamanho da Partícula , Urbanização , Emissões de Veículos/análise
7.
Environ Sci Pollut Res Int ; 21(14): 8610-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24728570

RESUMO

The mass concentration of carbonaceous species, organic carbon (OC), and elemental carbon (EC) using a semicontinuous thermo-optical EC-OC analyzer, and black carbon (BC) using an Aethalometer were measured simultaneously at an urban mega city Delhi in Ganga basin from January 2011 to May 2012. The concentrations of OC, EC, and BC exhibit seasonal variability, and their concentrations were ∼2 times higher during winter (OC 38.1 ± 17.9 µg m(-3), EC 15.8 ± 7.3 µg m(-3), and BC 10.1 ± 5.3 µg m(-3)) compared to those in summer (OC 14.1 ± 4.3 µg m(-3), EC 7.5 ± 1.5 µg m(-3), and BC 4.9 ± 1.5 µg m(-3)). A significant correlation between OC and EC (R = 0.95, n = 232) indicate their common emission sources with relatively lower OC/EC ratio (range 1.0-3.6, mean 2.2 ± 0.5) suggests fossil fuel emission as a major source of carbonaceous aerosols over the station. On average, mass concentration of EC was found to be ∼38 % higher than BC during the study period. The measured absorption coefficient (babs) was significantly correlated with EC, suggesting EC as a major absorbing species in ambient aerosols at Delhi. Furthermore, the estimated mass absorption efficiency (σabs) values are similar during winter (5.0 ± 1.5 m(2) g(-1)) and summer (4.8 ± 2.8 m(2) g(-1)). Significantly high aerosol loading of carbonaceous species emphasize an urgent need to focus on air quality management and proper impact assessment on health perspective in these regions.


Assuntos
Poluentes Atmosféricos/análise , Carbono/análise , Compostos Orgânicos/análise , Aerossóis , Cidades , Monitoramento Ambiental , Índia , Estações do Ano , Fuligem/análise
8.
PLoS One ; 5(6): e11122, 2010 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-20585397

RESUMO

BACKGROUND: There is an urgent need for an improved understanding of the sources, distributions and properties of atmospheric aerosol in order to control the atmospheric pollution over northeastern Himalayas where rising anthropogenic interferences from rapid urbanization and development is becoming an increasing concern. METHODOLOGY/PRINCIPAL FINDINGS: An extensive aerosol sampling program was conducted in Darjeeling (altitude approximately 2200 meter above sea level (masl), latitude 27 degrees 01'N and longitude 88 degrees 15'E), a high altitude station in northeastern Himalayas, during January-December 2005. Samples were collected using a respirable dust sampler and a fine dust sampler simultaneously. Ion chromatograph was used to analyze the water soluble ionic species of aerosol. The average concentrations of fine and coarse mode aerosol were found to be 29.5+/-20.8 microg m(-3) and 19.6+/-11.1 microg m(-3) respectively. Fine mode aerosol dominated during dry seasons and coarse mode aerosol dominated during monsoon. Nitrate existed as NH(4)NO(3) in fine mode aerosol during winter and as NaNO(3) in coarse mode aerosol during monsoon. Gas phase photochemical oxidation of SO(2) during premonsoon and aqueous phase oxidation during winter and postmonsoon were the major pathways for the formation of SO(4)(2-) in the atmosphere. Long range transport of dust aerosol from arid regions of western India was observed during premonsoon. The acidity of fine mode aerosol was higher in dry seasons compared to monsoon whereas the coarse mode acidity was higher in monsoon compared to dry seasons. Biomass burning, vehicular emissions and dust particles were the major types of aerosol from local and continental regions whereas sea salt particles were the major types of aerosol from marine source regions. CONCLUSIONS/SIGNIFICANCE: The year-long data presented in this paper provide substantial improvements to the heretofore poor knowledge regarding aerosol chemistry over northeastern Himalayas, and should be useful to policy makers in making control strategies.


Assuntos
Aerossóis , Poluentes Atmosféricos/análise , Altitude , Índia , Meteorologia , Oxirredução
9.
RNA ; 10(11): 1798-812, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15496525

RESUMO

The RimM protein in Escherichia coli is associated with free 30S ribosomal subunits but not with 70S ribosomes. A DeltarimM mutant is defective in 30S maturation and accumulates 17S rRNA. To study the interaction of RimM with the 30S and its involvement in 30S maturation, RimM amino acid substitution mutants were constructed. A mutant RimM (RimM-YY-->AA), containing alanine substitutions for two adjacent tyrosines within the PRC beta-barrel domain, showed a reduced binding to 30S and an accumulation of 17S rRNA compared to wild-type RimM. The (RimM-YY-->AA) and DeltarimM mutants had significantly lower amounts of polysomes and also reduced levels of 30S relative to 50S compared to a wild-type strain. A mutation in rpsS, which encodes r-protein S19, suppressed the polysome- and 16S rRNA processing deficiencies of the RimM-YY-->AA but not that of the DeltarimM mutant. A mutation in rpsM, which encodes r-protein S13, suppressed the polysome deficiency of both rimM mutants. Suppressor mutations, found in either helices 31 or 33b of 16S rRNA, improved growth of both the RimM-YY-->AA and DeltarimM mutants. However, they suppressed the 16S rRNA processing deficiency of the RimM-YY-->AA mutant more efficiently than that of the DeltarimM mutant. Helices 31 and 33b are known to interact with S13 and S19, respectively, and S13 is known to interact with S19. A GST-RimM but not a GST-RimM(YY-->AA) protein bound strongly to S19 in 30S. Thus, RimM likely facilitates maturation of the region of the head of 30S that contains S13 and S19 as well as helices 31 and 33b.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas Ribossômicas/química , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Alanina/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Glutationa Transferase/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Estrutura Terciária de Proteína , Processamento Pós-Transcricional do RNA , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Proteínas de Ligação a RNA , Proteínas Recombinantes/metabolismo , Proteínas Ribossômicas/genética , Homologia de Sequência de Aminoácidos , Tirosina/metabolismo
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