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1.
Ann Med Surg (Lond) ; 85(5): 2270-2272, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37229059

RESUMO

Electronic cigarettes, or "vaping," are battery-operated devices that heat a liquid containing propylene glycol, nicotine, and some flavoring agents, which aerosolize to produce vapors that the user inhales. They were introduced in 2003 and became popular worldwide as a less irritating alternative to combustible cigarettes. While they were initially advertised as smoking cessation aids, their use has taken the shape of an epidemic in some regions of the world. Vaping prevalence is high in South Asia, where a significant number of people use tobacco and smokeless tobacco. According to data from Pakistan, 6.2% of the population uses vaping/e-cigarettes, while 15.9 million (12.4%) use smokeless tobacco. Vaping may be a safer alternative to cigarette smoking, as e-cigarettes do not contain all the toxins that regular cigarettes do, and the aerosol from e-cigarettes has no appreciable cytotoxic, genotoxic, or inflammatory effects when inhaled. However, nicotine addiction is a concern, as it is the main culprit behind smoking addiction, and e-cigarettes may become a new pathway toward nicotine addiction. Hence, their effectiveness in smoking cessation is still debatable, and their role as a tool for smoking cessation needs further research.

2.
Indian J Pharm Sci ; 76(3): 251-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25035539

RESUMO

Ballota limbata (Lamiaceae) has been used for its antispasmodic, antiulcer, diuretic, vermifuge and sedative effects in folk medicine. However, little is known about how does it work to produce these therapeutic actions. Present research investigated phytochemical components and antioxidant properties of methanol extract and different fractions of Ballota limbata. In this study, phytochemical investigation was done by performing different chemical tests. Here, antioxidant property of the extract and fractions was investigated by using 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity, total antioxidant activity by the phosphomolybdenum method, linoleic acid peroxidation, ferric thiocyanate analysis and ferric-reducing antioxidant power. Methanol extract and fractions showed presence of numerous chemical principles including alkaloids, cardiac glycosides, tannins and flavonoids. The ethyl acetate fraction exhibited higher scavenging activity compared to the other fractions under investigation. This fraction displayed 84.16±1.02% 1,1-diphenyl-2-picryl hydrazyl radical inhibition at a dose of 60 µg/ml. IC50 for 1,1-diphenyl-2-picryl hydrazylradical-scavenging activity was 13.53±0.22 µg/ml, relative to the standard, butylatedhydroxytoluene, having IC50 of 12.33±0.88 µg/ml. Thus, Ballota limbata showed significant antioxidant activity, which may contribute in the mechanism of above pharmacological actions.

3.
Arh Hig Rada Toksikol ; 64(1): 169-77, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23740557

RESUMO

Oxidative stress has recently been implicated as a factor in the mortality and morbidity induced by organophosphorus (OP) compound poisoning. An overwhelming number of research papers are based on studying at the cellular and organ level. Such studies have concluded that antioxidants can be used as an adjunct compound in the treatment of both chronic as well as acute OP poisoning. Still, the role of antioxidants in reducing the mortality and morbidity induced by OP compounds has scarcely been verified, as well as their role as adjunct treatment compounds for both structurally and functionally different OP compounds. The present review of the literature was undertaken to establish the role of antioxidants in survival studies following acute exposure to OP compounds. The review found no substantial evidence that antioxidants demonstrate any positive effect following extremely toxic poisoning. However, for a more comprehensive and rational conclusion, further research needs to be conducted.


Assuntos
Antioxidantes/metabolismo , Inibidores da Colinesterase/metabolismo , Inseticidas/intoxicação , Intoxicação por Organofosfatos/metabolismo , Estresse Oxidativo , Humanos
4.
Indian J Chest Dis Allied Sci ; 54(2): 111-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22973780

RESUMO

BACKGROUND AND OBJECTIVES: This study compares the frequency of undiagnosed chronic obstructive pulmonary disease (COPD) in tobacco smokers suffering from ischaemic heart disease (IHD) and analyses the association of COPD severity with status, type and duration of smoking. METHODS: An analytical cross-sectional study conducted in current and former cigarette, hookah and combined cigarette and hookah smokers with IHD to detect previously undiagnosed COPD through spirometry. RESULTS: Among 124 males with IHD, majority [74 (59.7%)] were former smokers and were in the age ranged between 42 to 78 years. All had dyspnoea up to grade 4 and 64 (51.6%) also reported chronic cough and sputum production. According to type of smoking, 64 (51.6%) smoked cigarettes, 30 (24.2%) smoked hookah and 30 (24.2%) smoked both hookah and cigarettes. Forty-seven (37.9%) were found to have COPD, 24 (37.5%) among cigarette smokers, 12 (40%) among hookah smokers, while 11 (36.7%) were from cigarette and hookah smokers. Duration of smoking, its type and magnitude had no association with severity of COPD. CONCLUSIONS: The frequency of undiagnosed COPD is high in smokers with IHD. Hookah and combined hookah and cigarette smokers are almost as susceptible to develop COPD as are cigarette smokers.


Assuntos
Isquemia Miocárdica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumar/efeitos adversos , Idoso , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Paquistão/epidemiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/etiologia , Índice de Gravidade de Doença
5.
Theor Appl Genet ; 110(7): 1195-202, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15761718

RESUMO

The most popular retrotransposon-based molecular marker system in use at the present time is the sequence-specific amplification polymorphism (SSAP) system . This system exploits the insertional polymorphism of long terminal repeat (LTR) retrotransposons around the genome. Because the LTR sequence is used to design primers for this method, its successful application requires sequence information from the terminal region of the mobile elements . In this study, two LTR sequences were isolated from the cashew genome and used successfully to develop SSAP marker systems. These were shown to have higher levels of polymorphism than amplified fragment length polymorphic markers for this species.


Assuntos
Anacardium/genética , Marcadores Genéticos/genética , Polimorfismo Genético , Retroelementos/genética , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Componentes do Gene , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Sequências Repetidas Terminais/genética
6.
Heredity (Edinb) ; 94(3): 295-304, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15316557

RESUMO

The underlying mechanisms for hybrid vigor or heterosis are elusive. Here we report a population of recombinant inbred lines (RILs), derived from the two ecotypes, Col and Ler, which can serve as a permanent resource for studying the molecular basis of hybrid vigor in Arabidopsis. Using a North Carolina mating design III (NCIII), we determined the additive and dominant nature of gene action in this population. We detected heterosis among crosses of RILs with one of the two parents (Col and Ler) and analyzed genotypes and heterozygosities for RILs and test cross families (RILs crossed to Col and Ler) using a total of 446 published molecular markers. The performance of RILs and additive and dominant components in the test cross families were used to analyze QTLs for 16 traits, using QTL cartographer and composite interval mapping with 1,000 permutations for each trait. Our data suggest that locus-specific and/or genome-wide differential heterozygosity, including epistasis, plays an important role in the generation of the observed heterosis. Furthermore, the hybrid vigor occurred between two closely related ecotypes, and provides a general mechanism for novel variation generated between genetically similar materials.


Assuntos
Arabidopsis/genética , Marcadores Genéticos , Genótipo , Vigor Híbrido/genética , Meio Ambiente , Epistasia Genética , Variação Genética , Heterozigoto
7.
Theor Appl Genet ; 108(2): 280-91, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14513220

RESUMO

Cotton, the leading natural fiber crop, is largely produced by two primary cultivated allotetraploid species known as Upland or American cotton ( Gossypium hirsutum L.) and Pima or Egyptian cotton ( G. barbadense L.). The allotetraploid species diverged from each other and from their diploid progenitors (A or D genome) through selection and domestication after polyploidization. To analyze cotton AD genomes and dissect agronomic traits, we have developed a genetic map in an F2 population derived from interspecific hybrids between G. hirsutum L. cv. Acala-44 and G. barbadense L. cv. Pima S-7. A total of 392 genetic loci, including 333 amplified fragment length polymorphisms (AFLPs), 47 simple sequence repeats (SSRs), and 12 restriction fragment length polymorphisms (RFLPs), were mapped in 42 linkage groups, which span 3,287 cM and cover approximately 70% of the genome. Using chromosomal aneuploid interspecific hybrids and a set of 29 RFLP and SSR framework markers, we assigned 19 linkage groups involving 223 loci to 12 chromosomes. Comparing four pairs of homoeologous chromosomes, we found that with one exception linkage distances in the A-subgenome chromosomes were larger than those in their D-subgenome homoeologues, reflecting higher recombination frequencies and/or larger chromosomes in the A subgenome. Segregation distortion was observed in 30 out of 392 loci mapped in cotton. Moreover, approximately 29% of the RFLPs behaved as dominant loci, which may result from rapid genomic changes. The cotton genetic map was used for quantitative trait loci (QTL) analysis using composite interval mapping and permutation tests. We detected seven QTLs for six fiber-related traits; five of these were distributed among A-subgenome chromosomes, the genome donor of fiber traits. The detection of QTLs in both the A subgenome in this study and the D subgenome in a previous study suggests that fiber-related traits are controlled by the genes in homoeologous genomes, which are subjected to selection and domestication. Some chromosomes contain clusters of QTLs and presumably contribute to the large amount of phenotypic variation that is present for fiber-related traits.


Assuntos
Ligação Genética , Gossypium/crescimento & desenvolvimento , Gossypium/genética , Poliploidia , Locos de Características Quantitativas , Mapeamento Cromossômico , Segregação de Cromossomos , Cromossomos de Plantas , DNA de Plantas , Marcadores Genéticos , Genoma de Planta , Fenótipo , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Técnica de Amplificação ao Acaso de DNA Polimórfico
8.
Heredity (Edinb) ; 91(5): 456-64, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14576738

RESUMO

The genetic control of 22 quantitative traits, including developmental rates and sizes, was examined in generations of Arabidopsis thaliana derived from the cross between the ecotypes, Columbia (Col) and Landsberg erecta (Ler). The data were obtained from three sets of families raised in the same trial: the 16 basic generations, that is, parents, F(1)'s, F(2)'s, backcrosses, recombinant inbred lines (RILs) and a triple test cross (TTC), the latter produced by crossing the RILs to Col, Ler and their F(1). The data were analysed by two approaches. The first (approach A) involved traditional generation mean and variance component analysis and the second (B), based around the RILs and TTC families, involved marker-based QTL analysis. From (A), genetic differences between Col and Ler were detected for all traits with moderate heritabilities. Height at flowering was the only trait to show heterosis. Dominance was partial to complete for all height traits, and there was no overdominance but there was strong evidence for directional dominance. For most other traits, dominance was ambidirectional and incomplete, with average dominance ratios of around 80%. Epistasis, particularly of the duplicate type that opposes dominance, was a common feature of all traits. The presence of epistasis must imply multiple QTL for all traits. The QTL analysis located 38 significant effects in four regions of chromosomes I, II, IV and V, but not III. QTL affecting rosette size and leaf number were identified in all four regions, with days to maturity on chromosomes IV and V. The only QTL for height was located at the expected position of the erecta gene (chromosome II; 50 cM), but the additive and dominance effects of this single QTL did not adequately explain the generation means. The possible involvement of other interacting height QTL is discussed.


Assuntos
Arabidopsis/genética , Padrões de Herança/genética , Modelos Genéticos , Fenótipo , Característica Quantitativa Herdável , Análise de Variância , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Mapeamento Cromossômico , Cruzamentos Genéticos , Locos de Características Quantitativas/genética , Fatores de Tempo
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