Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Environ Sci Pollut Res Int ; 30(11): 28947-28960, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36401694

RESUMEN

Tannery effluent contains a number of organic and inorganic elements as pollutants which reduce plant growth. To overcome shortage of water, use of diluted industrial wastewater such as tannery effluent can be a viable strategy for improving crop growth and yield. A pot experiment was conducted to determine the effects of tannery effluent and its various dilutions on physiological and biochemical characteristics of five cucurbitaceous vegetables. Tannery effluent was applied 0, 25, 50, 75 and 100% to 3-week-old plants of five cucurbitaceous vegetables (Cucurbita maxima, Luffa cylindrica, Citrullus vulgaris, Cucumis melo, and Praecitrullus fistulosus) for 4 weeks. Tannery effluent reduced the growth of all five cucrbitaceous vegetables. Diluted tannery effluent (25%) improved the growth of Cucurbita maxima, Citrullus vulgaris, and Cucumis melo. Moderately diluted (50%) did not affect the growth of Citrullus vulgaris and Cucumis melo. Toxic effects of tannery effluent were associated with high accumulation of heavy metals Cr, Cd, Mn, and Fe in leaves and roots. High accumulation of heavy metals in leaves reduced the accumulation of nutrients in leaves (N, P, K) and reduced photosynthetic pigments and photosynthetic rate. Changes in photosynthetic rates of all vegetable species due to tannery effluent were not associated with stomatal limitations (stomatal conductance, transpiration rate, internal CO2). Toxic effects of tannery effluent on plants also include changes in N-metabolism (amino acid and protein). However, extent of these adverse effects of tannery effluent on vegetables was species specific. It is suggested that Cucurbita maxima can be grown by supplying 25% tannery effluent, whereas Citrullus vulgaris and Cucumis melo can be grown with moderately diluted (50%) tannery effluent.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Verduras/metabolismo , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Fotosíntesis , Nutrientes , Residuos Industriales
2.
Front Plant Sci ; 13: 860664, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35401592

RESUMEN

The accumulation of cadmium (Cd) in leaves reduces photosynthetic capacity by degrading photosynthetic pigments, reducing photosystem II activity, and producing reactive oxygen species (ROS). Though it was demonstrated that the application of Methyl Jasmonate (MeJA) induces heavy metal (HM) stress tolerance in plants, its role in adjusting redox balance and photosynthetic machinery is unclear. In this study, the role of MeJA in modulating photosystem II (PSII) activity and antioxidant defense system was investigated to reduce the toxic effects of Cd on the growth of pea (Pisum sativum L.) cultivars. One-week-old seedlings of three pea varieties were subjected to Cd stress (0, 50, 100 µm), and MeJA (0, 1, 5, 10 µm) was applied as a foliar spray for 2 weeks. Cadmium stress reduced the growth of all three pea varieties. Cadmium stress decreased photosynthetic pigments [Chl a (58.15%), Chl b (48.97%), total Chl (51.9%) and carotenoids (44.01%)] and efficiency of photosystem II [Fv/Fm (19.52%) and Y(II; 67.67%)], while it substantially increased Cd accumulation along with an increase in ROS (79.09%) and lipid peroxidation (129.28%). However, such adverse effects of Cd stress varied in different pea varieties. Exogenous application of MeJA increased the activity of a battery of antioxidant enzymes [superoxide dismutase (33.68%), peroxidase (29.75%), and catalase (38.86%)], improved photosynthetic pigments and PSII efficiency. This led to improved growth of pea varieties under Cd stress, such as increased fresh and dry weights of shoots and roots. In addition, improvement in root biomass by MeJA was more significant than that of shoot biomass. Thus, the mitigating effect of MeJA was attributed to its role in cellular redox balance and photosynthetic machinery of pea plants when exposed to Cd stress.

3.
Genes (Basel) ; 14(1)2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36672744

RESUMEN

Plant salt tolerance is controlled by various physiological processes such as water and ion homeostasis, photosynthesis, and cellular redox balance, which are in turn controlled by gene expression. In the present study, plants of six canola cultivars (DGL, Dunkled, Faisal Canola, Cyclone, Legend, and Oscar) were evaluated for salt tolerance by subjecting them to 0 or 200 mM NaCl stress. Based on growth, cultivars DGL, Dunkled, and Faisal Canola were ranked as salt tolerant, while cultivars Cyclone, Legend, and Oscar were ranked as salt-sensitive ones. Differential salt tolerance in these canola cultivars was found to be associated with a relatively lower accumulation of Na+ and greater accumulation of K+ in the leaves, lower oxidative damage (MDA), and better antioxidative defense system (Superoxide dismutase, SOD; peroxidase, POD, and catalase, CAT). Cultivar Oscar was the poorest to discriminate Na+ and K+ uptake and accumulation in leaves and had poor antioxidant potential to scavenge ROS. Salt stress did not affect the structural stability of photosystem-II (PSII) till three weeks, thereafter it caused a significant decrease. Salt stress increased the performance index (PIABS) by increasing the density of active reaction centers in Oscar. Salt stress decreased the antenna size thereby lowering the absorption and trapping energy flux, and maintaining the electron transport with an increase in heat dissipation. This may represent a potential mechanism to cope with salt stress. Transcriptome analysis of salt-sensitive cultivar Oscar further revealed that salt stress down-regulated DEGs related to hormonal signal transduction pathways, photosynthesis, and transcription factors, while DEGs related to the biosynthesis of amino acid and ion transport were up-regulated. In conclusion, salt tolerance in canola cultivars was associated with ion exclusion and maintenance of photosynthesis. Salt stress sensitivity in cultivar Oscar was mainly associated with poor control of ion homeostasis which caused oxidative stress and reduced photosynthetic efficiency.


Asunto(s)
Brassica napus , Brassica napus/genética , Brassica napus/metabolismo , Tolerancia a la Sal/genética , Antioxidantes/metabolismo , Fotosíntesis , Perfilación de la Expresión Génica
4.
Front Plant Sci ; 13: 1102201, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36756234

RESUMEN

Mango (Mangifera indica) fruit is known for its taste, health benefits, and drought tolerance. Potassium (K+) is one of the most abundant ions in a plant cell. It is important for various biological functions related to plant growth, development, and flowering/fruiting. It significantly contributes to fruit yield, quality, and drought tolerance in plants. However, molecular mechanisms comprising K+ transport in mango are least known. In the present study, 37 members of K+ transport-related genes (PTGs) were identified in mango, which include 22 K+ transporters (16 HAKs, 1 HKT, and 6 KEAs) and 15 K+ channels (6 TPKs and 8 Shakers). All PTGs were predicted to be expressed at the plasma membrane and possess characteristic motifs and domains. Phylogenetic analysis identified a strong kinship of PTGs among Oryza sativa, Arabidopsis thaliana, Cicer arietinum, Malus domestica, and M. indica. The promoter analysis identified 60 types of cis-elements related to various biological processes. RNA-seq-based expression profiling identified that MiTPK1.2, MiHAK1, MiHAK2.1, HAK6.1, and MiAKT1.1 were most upregulated in roots and that MiKEA2, MiAKT2, and MiAKT1 were upregulated in leaves. Moreover, MiAKT6, MiHAK1.1, MiKAT2, MiKAT2.1, MiHKT1, MiTPK1.1, MiHAK7, and MiHAK12 were highly expressed during the five growth stages of mango fruit. The current study is the first comprehensive report on K+ transport system in tropical fruits. Therefore, it will provide the foundation knowledge for the functional characterization of K+ genes in mango and related plants.

5.
Infect Drug Resist ; 15: 7699-7705, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36600953

RESUMEN

Introduction: Antibiotics are being used in humans and animals for treatment and control of bacterial infections. Excessive use of antibiotics in the production of poultry is a popular practice, but it poses serious health issues by transferring resistance from farm to humans via food or direct exposure. Study Objective: The objective of this study was to carry out a comparison of the resistance and sensitivity profile of isolated isolates from sewage of toilets that were in use of workers inside the farm and from sewage of household toilets. Methodology: In this study, a total of 320 sewage samples were collected. The antibiotic susceptibility profile was checked by Kirby-Bauer disc diffusion method, and the statistical analysis was carried out by MS excel. Chi-square test was performed to determine whether the antibiograms from two sample types were statistically different from each other or not. Results: From 320 sewage samples, a total of 296 bacterial isolates were isolated among which the leading bacterium was E. coli. The proportion of resistance, ESBL production and MDR was significantly higher in bacteria isolated from sewage of toilets under use of poultry farm workers as compared to the sewage from domestic use toilets. Conclusion: Resistance significantly increased in the bacteria isolated from toilets under use of poultry farm workers as compared to the ones isolated from control sewage samples.

6.
Sci Rep ; 11(1): 10854, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34035371

RESUMEN

Salt tolerant wheat cultivars may be used as genetic resource for wheat breeding to ensure yield stability in future. The study was aimed to select salt tolerant cultivar(s) to identify novel source of salt tolerance in local wheat germplasm. Initially, 40 local wheat cultivars were screened at 150 mM NaCl stress at seedling stage. Selected salt-tolerant (three; S-24, LU-26S and Pasban-90) and salt-sensitive (four; MH-97, Kohistan-97, Inqilab-91 and Iqbal-2000) wheat cultivars were further evaluated using growth, yield, biochemical and physiological attributes. Growth and yield of selected cultivars were reduced under salt stress due to decline in plant water status, limited uptake of macronutrients (N, P and K), reduced K+/Na+ ratio, photosynthetic pigments and quantum yield of PSII. Wheat plants tried to acclimate salt stress by osmotic adjustment (accumulation of total soluble sugars, proline and free amino acids). Degree of salinity tolerance in cvs. S-24 and LU-26S found to be associated with maintenance of K+/Na+ ratio, osmo-protectant and photosynthetic activity and can be used as donor for salt tolerance in wheat breeding program at least in Pakistan. These cultivars can be further characterized using molecular techniques to identify QTLs/genes for salt exclusion, osmo-protectant and photosynthetic activity for molecular breeding.


Asunto(s)
Potasio/metabolismo , Tolerancia a la Sal , Sodio/metabolismo , Triticum/crecimiento & desarrollo , Barajamiento de ADN , Ósmosis , Pakistán , Fotosíntesis , Fitomejoramiento , Semillas/crecimiento & desarrollo
7.
Plant Physiol Biochem ; 158: 244-254, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33221118

RESUMEN

Crop productivity is limited by several environmental constraints. Among these, salt stress plays a key role in limiting the growth and yield production of economically important agricultural crops. However, the exogenous fertigation of vitamins and minerals could serve as a "shot-gun" approach for offsetting the deleterious effects of salts present in the rhizosphere. Therefore, an experiment was conducted to quantify the efficacy of foliar fertigation of ascorbic acid (vitamin-C) and zinc (Zn) on the physio-biochemical attributes of barley (Hordeum vulgare L. Genotype B-14011) grown in a saline environment. The salt stress resulted in a reduced biological yield associated with a decrease in chlorophyll pigment, while a significant enhancement in Na+ and Zn2+ was observed under salinity stress. Similarly, the contents of total soluble proteins, total free amino acids, lipid peroxidation, and H2O2 and the activities of antioxidative enzymes (SOD, POD, CAT, APX and proline) were significantly enhanced under salinity stress. Moreover, salinity negatively affected the yield attributes and ion uptake of plants. However, foliar fertigation with AsA +0.03% Zn enhanced vegetative growth, photosynthetic pigments, synchronized ion uptake, the synthesis of enzymatic and non-enzymatic antioxidants, and the harvest index. It is inferred from this study that among all treatments, the effect of foliar fertigation with the AsA+0.03% Zn combination not only improved the salt stress tolerance but also improved the yield attributes, which will aid in the improvement in barley seed yield and is a step to solve the problem of malnutrition through biofortification of vitamin-C and zinc.


Asunto(s)
Antioxidantes/fisiología , Ácido Ascórbico/administración & dosificación , Hordeum/crecimiento & desarrollo , Estrés Salino , Zinc/administración & dosificación , Hordeum/enzimología , Peróxido de Hidrógeno , Hojas de la Planta
8.
Plants (Basel) ; 11(1)2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-35009006

RESUMEN

Potassium (K+) is one of the most important cations that plays a significant role in plants and constitutes up to 10% of plants' dry weight. Plants exhibit complex systems of transporters and channels for the distribution of K+ from soil to numerous parts of plants. In this study, we have identified 39 genes encoding putative K+ transport-related genes in Vigna radiata. Chromosomal mapping of these genes indicated an uneven distribution across eight out of 11 chromosomes. Comparative phylogenetic analysis of different plant species, i.e., V. radiata, Glycine max, Cicer arietinum, Oryza sativa, and Arabidopsis thaliana, showed their strong conservation in different plant species. Evolutionary analysis of these genes suggests that gene duplication is a major route of expansion for this family in V. radiata. Comprehensive promoter analysis identified several abiotic stresses related to cis-elements in the promoter regions of these genes, suggesting their role in abiotic stress tolerance. Our additional analyses indicated that abiotic stresses adversely affected the chlorophyll concentration, carotenoids, catalase, total soluble protein concentration, and the activities of superoxide and peroxidase in V. radiata. It also disturbs the ionic balance by decreasing the uptake of K+ content and increasing the uptake of Na+. Expression analysis from high-throughput sequencing data and quantitative real-time PCR experiments revealed that several K+ transport genes were expressed in different tissues (seed, flower, and pod) and in abiotic stress-responsive manners. A highly significant variation of expression was observed for VrHKT (1.1 and 1.2), VrKAT (1 and 2) VrAKT1.1, VrAKT2, VrSKOR, VrKEA5, VrTPK3, and VrKUP/HAK/KT (4, 5, and 8.1) in response to drought, heat or salinity stress. It reflected their potential roles in plant growth, development, or stress adaptations. The present study gives an in-depth understanding of K+ transport system genes in V. radiata and will serve as a basis for a functional analysis of these genes.

9.
J Cell Biochem ; 121(2): 898-929, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31478252

RESUMEN

The established concept that RNA works only for protein synthesis has been changed over the past few decades and shifted towards therapeutic purposes. Almost 98% of mammalian genome is transcribed into nonprotein coding RNA termed as noncoding RNA (ncRNA) which plays regulatory role in molecular and cellular functions as controlling gene expression. These ncRNAs are classified as long noncoding RNA (lncRNA), short noncoding RNA (sncRNA), and translational/structural RNA which possess diverse functions. These ncRNAs regulate expression of normal gene and modulate disease development and progression. The characterization of ncRNA genes and their mechanisms can aid in disease diagnosis, examining its development and direct specific therapies in different disease treatments. Due to their unique modes of action, they are designated as novel class of targets leading to drug discovery. The modulation in these ncRNAs can enhance therapeutic treatments against different diseases by targeting mRNA for its cleavage via antisense olionucleotides (ASOs)/DNA duplex, RNA alternative splicing/editing, chromatin modification, transcriptional/translational interference, RNA masking, small interfering RNA/microRNA-based gene silencing and by inducing immunity via RNA-based vaccination. Here in this review, we tried to summarize the emerging fields of ncRNA, their role in different diseases, their modes of action, and their potential in target identification and therapeutic drug development.


Asunto(s)
Enfermedad Crónica/terapia , Descubrimiento de Drogas , MicroARNs/uso terapéutico , Terapia Molecular Dirigida , ARN Mensajero/uso terapéutico , ARN Interferente Pequeño/uso terapéutico , ARN Pequeño no Traducido/uso terapéutico , Animales , Humanos
10.
Ann Hum Genet ; 83(6): 426-433, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31069794

RESUMEN

Tuberculosis (TB) is a global issue as one-third of the population worldwide is considered to be infected. TB has become a critical public health problem as a result of increasing drug resistance, which poses a challenge to current control strategies. Similar to environmental factors, genetic makeup of the host equally contributes to disease onset. We performed genotypic analysis to examine the relationship between IFNG and TB onset and drug resistance in a Pakistani population comprising 689 subjects. Notable differences were observed in the IFNG polymorphism (+874T/A) between the case and control groups. The frequency of the wild-type genotype (TT) in the controls (43.2%) was significantly higher than in the cases (25.3%) (odds ratio [OR] = 0.77, p < 0.0001), while the mutant genotype frequency (AA) (38.57%) in the cases was significantly higher than in the controls (22.6%) (OR = 1.46, p < 0.0001). The heterozygous genotype frequency (TA) did not significantly differ between the control and case groups. Compared with the controls, the variant allele (A) was approximately twice as frequent in the cases. Females and older people have a higher chance of disease development. Finally, the IFNG (+874T/A) polymorphism was not associated with drug sensitivity or resistance. However, a genotypic polymorphism of IFNG (+874T/A) was significantly associated with susceptibility to TB, and the T allele conferred protection against TB. Additional studies involving larger cohorts are needed to further explore this relationship between genetics and disease vulnerability.


Asunto(s)
Predisposición Genética a la Enfermedad , Interferón gamma/genética , Polimorfismo de Nucleótido Simple , Tuberculosis/epidemiología , Tuberculosis/genética , Adolescente , Adulto , Anciano , Niño , Farmacorresistencia Bacteriana , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pakistán/epidemiología , Fenotipo , Vigilancia de la Población , Tuberculosis/diagnóstico , Adulto Joven
11.
Braz J Microbiol ; 50(2): 429-434, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30805894

RESUMEN

Tuberculosis is becoming a global issue with raising occurrences; particularly in developing countries, the situation is alarming. Besides environmental factors, host genetic factors are vital in disease development. A demographical and genotypic analysis in relation to tuberculosis commencement is conducted in a Pakistani population, and genotypic frequency of EBI3 (rs4740) was analyzed. Allelic frequencies of EBI3 (rs4740) were significantly associated with disease susceptibility in the reviewed population. Analysis for EBI3 (rs4740) genotyping showed a significant association of "GG" with reduced risk for disease. Moreover, females and older age found to be more perilous to develop TB while smoking and a family history of TB are additional risk factors for disease development. Further work with a larger population is necessary to identify the true causative variants of tuberculosis.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Interleucinas/genética , Antígenos de Histocompatibilidad Menor/genética , Tuberculosis Pulmonar/genética , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/inmunología , Pakistán , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Fumar/efectos adversos , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/microbiología , Adulto Joven
12.
Appl Biochem Biotechnol ; 186(2): 306-334, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29611134

RESUMEN

Salinity is one of the major threats faced by the modern agriculture today. It causes multidimensional effects on plants. These effects depend upon the plant growth stage, intensity, and duration of the stress. All these lead to stunted growth and reduced yield, ultimately inducing economic loss to the farming community in particular and to the country in general. The soil conditions of agricultural land are deteriorating at an alarming rate. Plants assess the stress conditions, transmit the specific stress signals, and then initiate the response against that stress. A more complete understanding of plant response mechanisms and their practical incorporation in crop improvement is an essential step towards achieving the goal of sustainable agricultural development. Literature survey shows that investigations of plant stresses response mechanism are the focus area of research for plant scientists. Although these efforts lead to reveal different plant response mechanisms against salt stress, yet many questions still need to be answered to get a clear picture of plant strategy to cope with salt stress. Moreover, these studies have indicated the presence of a complicated network of different integrated pathways. In order to work in a progressive way, a review of current knowledge is critical. Therefore, this review aims to provide an overview of our understanding of plant response to salt stress and to indicate some important yet unexplored dynamics to improve our knowledge that could ultimately lead towards crop improvement.


Asunto(s)
Fenómenos Fisiológicos de las Plantas/genética , Salinidad , Estrés Fisiológico/genética , Ácido Abscísico/metabolismo , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Desarrollo de la Planta , Plantas/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
13.
Environ Sci Pollut Res Int ; 23(18): 18320-31, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27278069

RESUMEN

Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and 5.0 % v/w basis). Crude oil contamination reduced soil microflora which may be beneficial to plant growth. It was observed that oil pollution caused a remarkable decrease in biomass, leaf water potential, turgor potential, photosynthetic pigments, quantum yield of photosystem II (PSII) (Fv/Fm), net CO2 assimilation rate, leaf nitrogen and total free amino acids. Gas exchange characteristics suggested that reduction in photosynthetic rate was mainly due to metabolic limitations. Fast chlorophyll a kinetic analysis suggested that crude oil damaged PSII donor and acceptor sides and downregulated electron transport as well as PSI end electron acceptors thereby resulting in lower PSII efficiency in converting harvested light energy into biochemical energy. However, maize plants tried to acclimate to moderate level of oil pollution by increasing root diameter and root length relative to its shoot biomass, to uptake more water and mineral nutrients.


Asunto(s)
Petróleo/metabolismo , Fotosíntesis , Zea mays/metabolismo , Clorofila/metabolismo , Clorofila A , Transporte de Electrón , Cinética , Luz , Contaminación por Petróleo/análisis , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Agua/metabolismo , Zea mays/crecimiento & desarrollo
14.
Water Environ Res ; 87(12): 2065-75, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26156220

RESUMEN

Remediation of colored textile wastewaters is a matter of interest. In this study, 49 bacteria were isolated from the textile wastewater and tested for their ability to decolorize reactive yellow-2 (RY2) dye. The most efficient isolate, RN34, was identified through amplification, sequencing, and phylogenetic analysis of its 16S rDNA and was designated as Serratia sp. RN34. This bacterium was also found capable of decolorizing other related reactive azo-dyes, including reactive black-5, reactive red-120, and reactive orange-16 but at varying rates. The optimum pH for decolorization of RY2 by the strain RN34 was 7.5 using yeast extract as cosubstrate under static incubation at 30 °C. The strain RN34 also showed potential to decolorize RY2 in the presence of considerable amounts of hexavalent chromium and sodium chloride. A phytotoxicity study demonstrated relatively reduced toxicity of RY2 decolorized products on Vigna radiata plant as compared to the uninoculated RY2 solution.


Asunto(s)
Compuestos Azo/metabolismo , Reactores Biológicos , Residuos Industriales/análisis , Serratia/metabolismo , Industria Textil , Triazinas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Compuestos Azo/química , Concentración de Iones de Hidrógeno , Triazinas/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Purificación del Agua
15.
Plant J ; 76(3): 466-80, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23952652

RESUMEN

Like their animal counterparts, plant glutamate receptor-like (GLR) homologs are intimately associated with Ca(2+) influx through plasma membrane and participate in various physiological processes. In pathogen-associated molecular patterns (PAMP)-/elicitor-mediated resistance, Ca(2+) fluxes are necessary for activating downstream signaling events related to plant defense. In this study, oligogalacturonides (OGs), which are endogenous elicitors derived from cell wall degradation, were used to investigate the role of Arabidopsis GLRs in defense signaling. Pharmacological investigations indicated that GLRs are partly involved in free cytosolic [Ca(2+)] ([Ca(2+)]cyt) variations, nitric oxide (NO) production, reactive oxygen species (ROS) production and expression of defense-related genes by OGs. In addition, wild-type Col-0 plants treated with the glutamate-receptor antagonist 6,7-dinitriquinoxaline-2,3-dione (DNQX) had a compromised resistance to Botrytis cinerea and Hyaloperonospora arabidopsidis. Moreover, we provide genetic evidence that AtGLR3.3 is a key component of resistance against H. arabidopsidis. In addition, some OGs-triggered immune events such as defense gene expression, NO and ROS production are also to different extents dependent on AtGLR3.3. Taken together, these data provide evidence for the involvement of GLRs in elicitor/pathogen-mediated plant defense signaling pathways in Arabidopsis thaliana.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/inmunología , Señalización del Calcio , Interacciones Huésped-Patógeno , Oomicetos/fisiología , Receptores de Glutamato/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Óxido Nítrico/metabolismo , Oligosacáridos/metabolismo , Inmunidad de la Planta , Especies Reactivas de Oxígeno/metabolismo , Receptores de Glutamato/genética , Transducción de Señal
16.
J Infect Dev Ctries ; 7(3): 220-8, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23493000

RESUMEN

INTRODUCTION: The etiological association of Helicobacter pylori with gastric ulcer (GU), gastric cancer (GC), and duodenal ulcer (DU) is well-known. Understanding the epidemiology of H. pylori facilitates the estimation of disease burden in a certain population. This study presents the diversity of H. pylori genotypes and their association with different clinical outcomes among dyspeptic patients in Pakistan over a period of four years. METHODOLOGY: Gastric biopsy samples from a total of 450 dyspeptic individualswere subjected to PCR, genotypingand histology. RESULTS: A total of 201 (45%) cases were found positive for H. pylori. The detection rate was high in GU (91%), DU (86%) and GC (83%) cases compared with those cases who had intact gastric mucosa (18%). Histology revealed the presence of infection in 68% of cases of mild/chronic nonspecific gastritis with others belonging to the GU sequel. cagA gene carriage was observed in 104 (51%) cases or mostly from DU, GU and GC groups, of which 97 were Western type strains while 3 were East-Asian type strains that are rarely observed in South Asia. vacA allelic variant s1am1 was most commonly observed, followed by s1am2, and s1bm1, with direct correlation in diseased cases (gastritis, GU, DU and GC). Prevalent genotypic combinations were s1am1/cagA- in gastritis and s1am1/cagA+ in DU, GU, and GC. CONCLUSIONS: Our study indicates the predominant circulation of Western type cagA and vacAs1am1 type H. pylori strains in Pakistan.


Asunto(s)
Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Niño , Femenino , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Variación Genética , Genotipo , Infecciones por Helicobacter/patología , Helicobacter pylori/clasificación , Histocitoquímica , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Pakistán/epidemiología , Reacción en Cadena de la Polimerasa , Prevalencia , Factores de Virulencia/genética , Adulto Joven
17.
World J Gastroenterol ; 18(18): 2245-52, 2012 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-22611319

RESUMEN

AIM: To determine antibiotic resistance of Helicobacter pylori (H. pylori) in Pakistan and its correlation with host and pathogen associated factors. METHODS: A total of 178 strains of H. pylori were isolated from gastric biopsies of dyspeptic patients. Susceptibility patterns against first and second-line antibiotics were determined and trends of resistance were analyzed in relation to the sampling period, gastric conditions and cagA gene carriage. The effect of cagA gene on the acquisition of resistance was investigated by mutant selection assay. RESULTS: The observations showed that monoresistant strains were prevalent with rates of 89% for metronidazole, 36% for clarithromycin, 37% for amoxicillin, 18.5% for ofloxacin and 12% for tetracycline. Furthermore, clarithromycin resistance was on the rise from 2005 to 2008 (32% vs 38%, P = 0.004) and it is significantly observed in non ulcerative dyspeptic patients compared to gastritis, gastric ulcer and duodenal ulcer cases (53% vs 20%, 18% and 19%, P = 0.000). On the contrary, metronidazole and ofloxacin resistance were more common in gastritis and gastric ulcer cases. Distribution analysis and frequencies of resistant mutants in vitro correlated with the absence of cagA gene with metronidazole and ofloxacin resistance. CONCLUSION: The study confirms the alarming levels of antibiotic resistance associated with the degree of gastric inflammation and cagA gene carriage in H. pylori strains.


Asunto(s)
Antibacterianos/uso terapéutico , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Estómago/microbiología , Biopsia , Distribución de Chi-Cuadrado , Análisis Mutacional de ADN , Infecciones por Helicobacter/epidemiología , Humanos , Modelos Lineales , Pruebas de Sensibilidad Microbiana , Mutación , Pakistán/epidemiología
18.
Cell Calcium ; 51(6): 434-44, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22410211

RESUMEN

Calcium signatures induced by two elicitors of plant defense reactions, namely cryptogein and oligogalacturonides, were monitored at the subcellular level, using apoaequorin-transformed Nicotiana tabacum var Xanthi cells, in which the apoaequorin calcium sensor was targeted either to cytosol, mitochondria or chloroplasts. Our study showed that both elicitors induced specific Ca(2+) signatures in each compartment, with the most striking difference relying on duration. Common properties also emerged from the analysis of Ca(2+) signatures: both elicitors induced a biphasic cytosolic [Ca(2+)] elevation together with a single mitochondrial [Ca(2+)] elevation concomitant with the first cytosolic [Ca(2+)] peak. In addition, both elicitors induced a chloroplastic [Ca(2+)] elevation peaking later in comparison to cytosolic [Ca(2+)] elevation. In cryptogein-treated cells, pharmacological studies indicated that IP(3) should play an important role in Ca(2+) signaling contrarily to cADPR or nitric oxide, which have limited or no effect on [Ca(2+)] variations. Our data also showed that, depending on [Ca(2+)] fluxes at the plasma membrane, cryptogein triggered a mitochondrial respiration increase and affected excess energy dissipation mechanisms in chloroplasts. Altogether the results indicate that cryptogein profoundly impacted cell functions at many levels, including organelles.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Calcio/química , Citosol/química , Nicotiana/química , Células Vegetales/efectos de los fármacos , Antiportadores/química , Proteínas de Transporte de Catión/química , Membrana Celular/química , Clorofila/química , Cloroplastos/química , Cloroplastos/efectos de los fármacos , Fluorescencia , Proteínas Fúngicas/farmacología , Mitocondrias/química , Mitocondrias/efectos de los fármacos , Oxígeno/química , Phytophthora/química , Células Vegetales/química , Factores de Tiempo , Nicotiana/citología , Nicotiana/efectos de los fármacos
19.
Plant Sci ; 181(5): 527-33, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21893248

RESUMEN

Increasing evidences support the assumption that nitric oxide (NO) acts as a physiological mediator in plants. Understanding its pleiotropic effects requires a deep analysis of the molecular mechanisms underlying its mode of action. In the recent years, efforts have been made in the identification of plant proteins modified by NO at the post-translational level, notably by S-nitrosylation. This reversible process involves the formation of a covalent bond between NO and reactive cysteine residues. This research has now born fruits and numerous proteins regulated by S-nitrosylation have been identified and characterized. This review describes the basic principle of S-nitrosylation as well as the Biotin Switch Technique and its recent adaptations allowing the identification of S-nitrosylated proteins in physiological contexts. The impact of S-nitrosylation on the structure/function of selected proteins is further discussed.


Asunto(s)
Óxido Nítrico/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Procesamiento Proteico-Postraduccional , Óxido Nítrico/química , Proteínas de Plantas/química
20.
J Pak Med Assoc ; 59(7): 461-3, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19579735

RESUMEN

OBJECTIVE: To compare the acceptable colonoscopy completion rates in three successive audits, identifying the reasons for failure of completion and rectifying them to improve the performance at our endoscopy unit. METHODS: Study was conducted at Endoscopy unit of Medical Unit One Civil Hospital Karachi. The first audit was conducted retrospectively on the colonoscopy results, done from November 2004 to November 2005. As the information was incomplete, a performa was designed for the next prospective audit from December 2005 to November 2006. The shortcomings found in the results of this audit were improved in the third audit done prospectively from December 2006 to November 2007. RESULTS: In the first audit 164 patients (111 male) underwent colonoscopy. The mean age was 40 +/- 10.08 years. The overall caecal intubation rate was 55%, but adjusted caecal intubation was not calculated because of inadequate documentation. In the second audit, 119 patients (66 male) underwent colonoscopy. The mean age was 45 +/- 10.17 years. After implementing changes the overall crude caecal intubation rate was 54.8% and the adjusted caecal intubation rate was 75% with exclusion of strictures and poor preparation. In the third audit, 122 patients (58 males) underwent colonoscopy. The mean age was 38 +/- 11.07 years. With further improvement in methodology the overall crude caecal intubation rate was (80.3%) and the adjusted caecal intubation rate was (98%). CONCLUSION: These audits allowed us to evaluate our endoscopy services and to detect the short comings and deviation from standard techniques and hence improving the performance in the subsequent year for the benefit of patients.


Asunto(s)
Colonoscopía , Intubación , Humanos , Estudios Prospectivos , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...