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1.
Pak J Med Sci ; 39(5): 1416-1421, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680793

RESUMO

Objectives: To assess the prevalence, pattern, and associated factors of dyslipidemia in patients with coronary artery disease (CAD) in the Northwest region of Pakistan. Method: A cross-sectional secondary data analysis was performed on CAD patients visiting cardiology clinics in selected hospitals from July to December 2019. A total of 362 patients were included via consecutive sampling. Dyslipidemia was operationalized according to the "National Cholesterol Education Program (NCEP ATP III) guidelines". Results: Mixed dyslipidemia was recorded in 92.26% of the patients, while isolated dyslipidemia was observed in 5.24%. A high prevalence of combined dyslipidemia with increased LDL-C, TG, and low HDL-C was noted. Contrarily, elevated LDL-C was the commonest single lipid disorder (84.25%). Hypercholesterolemia was the least common disorder. Increasing BMI was found to be independently associated with hypercholesterolemia (OR: 1.19). Similarly, age (OR: 0.97) and being a rural resident (OR: 2.61) were independent factors associated with hypertriglyceridemia. Furthermore, being an urban resident (OR: 2.25) and increasing BMI (OR: 1.77) were also significantly associated with high LDL-C. Conclusion: Mixed dyslipidemias were observed in the majority of the patients. Age, BMI, and residence were noted to be independently associated with abnormal lipids. Early screening and proper management should be encouraged to minimize this significant cardiovascular risk.

4.
J Ayub Med Coll Abbottabad ; 34(4): 817-822, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36566406

RESUMO

BACKGROUND: We tested the utility of mini-pool PCR testing for the rational use of PCR consumables in screening for CoViD-19. METHODS: After pilot experiments, 3-samples pool size was selected. One step RT-PCR was performed. The samples in the mini-pool having COVID gene amplification were tested individually. RESULTS: 1548 samples tested in 516 mini-pools resulted 396 mini-pools as negative and 120 as positive. Upon individual testing, 110 samples tested positive and 9 were inconclusive. 876 PCR reactions were performed to test 1548 samples, saving 43% PCR reagents. Centres with low prevalence resulted in most saving on reagents (50%), while centres with high prevalence resulted in more test reactions. Testing of individual samples resulted in delays in reporting. CONCLUSIONS: Pooling can increase lab capacity, however, pooling delays results and cause degradation of samples.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2/genética , Teste para COVID-19 , Paquistão/epidemiologia , Manejo de Espécimes/métodos , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , RNA Viral
5.
Int Immunopharmacol ; 112: 109246, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36116153

RESUMO

Vincristine induced peripheral neuropathy (VIPN) is a serious untoward side effect suffered by cancer patients, which still lacks an adequate therapeutic approach. This study examined the alleviating potential of novel methanimine derivatives i.e. (E)-N-(4-nitrobenzylidene)-4-chloro-2-iodobenzamine (KB 9) and (E)-N-(2-methylbenzylidene)-4-chloro-2-iodobenzamine (KB 10) in VIPN. Vincristine was injected in BALB/c mice for 10 days to instigate nociceptive neuropathy. Dynamic and static allodynia, thermal (hot and cold) hyperalgesia were evaluated at 0, 5, 10 and 14 days using cotton brush, Von Frey filament application, hot plate test, acetone drop and cold water respectively. Tumour necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), lipid peroxide (LPO), glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and reactive oxygen species (ROS) assays were performed to assess the efficacy of KB9 and KB10 against neuroinflammation and oxidative stress utilizing ELISA, immunohistochemistry and western blot analysis in brain and sciatic nerve tissues. Computational studies were executed to determine the stable binding conformation of both compounds with respect to COX-2 and NF-κB. Interestingly, both compounds substantially reduced protein expression related to neuroinflammation, oxidative stress (LPO, GST, SOD, CAT) and pain (NF-κB, COX-2, IL-1ß and TNF-α). This molecular analysis suggested that the neuroprotective effect of KB9 and KB10 was mediated via regulation of inflammatory signaling pathways. Overall, this study demonstrated that KB9 and KB10 ameliorated vincristine induced neuropathy, through anti-inflammatory, anti-nociceptive and antioxidant mechanisms.


Assuntos
Fármacos Neuroprotetores , Doenças do Sistema Nervoso Periférico , Camundongos , Animais , Vincristina/farmacologia , Catalase/metabolismo , Antioxidantes/uso terapêutico , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Espécies Reativas de Oxigênio , Fármacos Neuroprotetores/farmacologia , NF-kappa B/metabolismo , Ciclo-Oxigenase 2/metabolismo , Peróxidos Lipídicos/farmacologia , Acetona/farmacologia , Acetona/uso terapêutico , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/patologia , Estresse Oxidativo , Hiperalgesia/tratamento farmacológico , Superóxido Dismutase/metabolismo , Glutationa/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Água , Transferases/metabolismo , Transferases/farmacologia , Transferases/uso terapêutico
6.
Int J Mol Sci ; 24(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36613586

RESUMO

This review article is built on the beneficial effects of Lactobacillus against different diseases, and a special focus has been made on its effects against neurological disorders, such as depression, multiple sclerosis, Alzheimer's, and Parkinson's disease. Probiotics are live microbes, which are found in fermented foods, beverages, and cultured milk and, when administered in an adequate dose, confer health benefits to the host. They are known as "health-friendly bacteria", normally residing in the human gut and involved in maintaining homeostatic conditions. Imbalance in gut microbiota results in the pathophysiology of several diseases entailing the GIT tract, skin, immune system, inflammation, and gut-brain axis. Recently, the use of probiotics has gained tremendous interest, because of their profound effects on the management of these disease conditions. Recent findings suggest that probiotics enrichment in different human and mouse disease models showed promising beneficial effects and results in the amelioration of disease symptoms. Thus, this review focuses on the current probiotics-based products, different disease models, variable markers measured during trials, and evidence obtained from past studies on the use of probiotics in the prevention and treatment of different diseases, covering the skin to the central nervous system diseases.


Assuntos
Doenças do Sistema Nervoso Central , Microbioma Gastrointestinal , Probióticos , Animais , Humanos , Camundongos , Lactobacillus , Probióticos/farmacologia , Probióticos/uso terapêutico
7.
Neurotoxicology ; 87: 1-10, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34428482

RESUMO

Herein, we evaluated the neuroprotective effect of melatonin against cisplatin-induced oxidative damage, neuroinflammation, and synaptic dysfunction in mice. Cisplatin was administered at a dose of 2 mg/kg for eleven consecutive days to induce symptoms of cognitive impairment and neurodegeneration, while melatonin was administered at a 20 mg/kg dose for thirty consecutive days. We used various experimental techniques such as western blotting, immunofluorescence analysis, and oxidative stress marker assays to support our notion. Moreover, for cognitive impairment, we conducted behavioral analyses such as Morris Water Maze (MWM) and Y-Maze tests. The results indicated that melatonin attenuated oxidative stress by upregulating the expression of NF-E2-related factor-2 (Nrf2) dependent anti-oxidative protein levels. Similarly, melatonin positively modulated the expression of Sirt1 (a member of the sirtuin family), Phospho-AMPKα (Thr172), peroxisome proliferator-activated receptor (PPARγ), PPAR gamma coactivator 1 alpha (PGC-1α) coupled to downregulation of neuroinflammatory mediators and markers such as nuclear factor kappa-B (NF-κB), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1ß). Moreover, melatonin significantly upregulated the expression of synaptic markers such as postsynaptic density protein -95 (PSD-95), synaptosomal-associated protein 23 (SNAP-23), and synaptophysin compared to the cisplatin alone group. Furthermore, the results of behavior tests suggested that melatonin significantly improved the cognitive functions of the cisplatin injected mice.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Cisplatino/toxicidade , Melatonina/farmacologia , Doenças Neurodegenerativas/induzido quimicamente , Fármacos Neuroprotetores/farmacologia , Animais , Western Blotting , Cisplatino/antagonistas & inibidores , Imunofluorescência , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Teste do Labirinto Aquático de Morris , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neuroinflamatórias/induzido quimicamente , Doenças Neuroinflamatórias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
9.
PLoS One ; 15(9): e0228367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32976485

RESUMO

The Zigzag ladybird beetle, Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), is a biological control agent that feeds on a variety of aphid species. Life table and predation data of C. sexmaculata were collected under laboratory conditions at 25±2°C, 60±5% RH and L14: D10 h in connection with feeding on four different aphid species; Lipaphis erysimi (Kaltenbach), Myzus persicae (Sulzer), Aphis nerii (Boyer de Fonscolombe) and Diuraphis noxia (Mordvilko). Larval development of C. sexmaculata was long when fed on M. persicae (12.18 days) and shorter on D. noxia (10.64 days). The male's lifespan was longer on M. persicae (26.70 days) and shorter on L. erysimi (23.67 days). Fecundity was maximum when the beetle was fed D. noxia (316.8 eggs/female) and minimum on M. persicae (199.1 eggs/female). Net reproductive rate, intrinsic rate of increase and finite rate of increase were highest on D. noxia with values of 158.4 (offspring individual-1), 0.22 d-1, and 1.24 d-1, respectively whereas the respective parameters were lowest on L. erysimi (99.5 offspring individual-1, 0.19 d-1, and 1.20 d-1, respectively). However, the mean of the generation (T) was shorter on A. nerii (22.48 d-1) and longer on M. persicae (24.68 d-1). Based on life table parameters obtained under laboratory conditions, the most appropriate host of C. sexmaculata was D. noxia. This study should help us to improve mass rearing and use of C. sexmaculata in the biological control of aphids on field and horticultural crops.


Assuntos
Afídeos/parasitologia , Besouros/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório/fisiologia , Animais , Afídeos/fisiologia , Feminino , Fertilidade/fisiologia , Larva , Tábuas de Vida , Longevidade/fisiologia , Masculino , Paquistão
10.
Cureus ; 12(5): e7913, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32494528

RESUMO

Introduction Our objective was to determine the severity frequency of coronary artery disease (CAD) in prediabetes patients undergoing coronary angiography (CAG) in a catheterization laboratory. Materials and methods This descriptive comparative study was conducted on patients who were planned for elective CAG in the hospital from January 2019 to November 2019. The study includes patients age ≥40 years undergoing elective CAG with or without percutaneous coronary intervention/percutaneous transluminal coronary angioplasty. There were 458 patients (381 men and 77 women) in this study that were categorized into three groups on the basis on their glycated hemoglobin (HbA1c) levels: group I (n = 143) as non-diabetes, group II (n = 110) as prediabetes, and group III (n = 205) as diabetes. The severity of CAD was determined using the Gensini score. Results A total of 458 patients were included. Of these, 44.97% had hypertension; n = 36 (25.17%), n = 48 (43.63%), and n = 122 (59.51%) in group I, group II and group III, respectively (P = .0001). A total of 214 (46.72%) had a smoking history. There was a strong family history of CAD in group II (n = 29, 26.36%) and group III (n = 43, 20.98%). Group II and group III patients had a higher extension of CAD than group I (P = .01). Group II (n = 27, 41.54) and group III (n = 65, 50.39%) had a higher frequency of deployment of two stents compared to group I. Conclusion Coronary artery atherosclerosis disease increases parallel to the HbA1c severity and smoking. The present study emphasizes prediabetes as an independent risk factor for CAD.

11.
Int. microbiol ; 22(2): 191-201, jun. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184826

RESUMO

In this study, endophytic bacteria isolated from root, stem, and leaf tissues of stripe rust-susceptible (Inqilab 91, Galaxy 2013, and 15BT023) and stripe rust-resistant (NARC 2011, Ujala 2015, TW1410) cultivars were identified and characterized. Abundance of endophytes was found in roots as compared with stems and leaves. Resistant and susceptible cultivars significantly differed in abundance of endophytic bacteria. Restriction analysis of 16S rRNA genes amplified from 100 bacterial isolates produced 17 unique patterns. Representatives of each of the 17 unique patterns were sequenced and identified. Among the sequenced bacteria, 8 belonged to Firmicutes, 7 were Proteobacteria, and 2 were Actinobacteria. Most of the isolates have plant growth-promoting properties and a few have the potential of producing hydrolytic enzymes. Two isolates showed significant inhibition of rust spore germination. These endophytic bacteria not only can be helpful in growth-promoting activities but also can assist in biocontrol of stripe rust disease


No disponible


Assuntos
Endófitos/isolamento & purificação , Raízes de Plantas/microbiologia , Phakopsora pachyrhizi/isolamento & purificação , RNA Ribossômico 16S/isolamento & purificação , Bactérias/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Firmicutes/isolamento & purificação , Actinobacteria/enzimologia , Actinobacteria/isolamento & purificação , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação , Paquistão
12.
Int Microbiol ; 22(2): 191-201, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30810983

RESUMO

In this study, endophytic bacteria isolated from root, stem, and leaf tissues of stripe rust-susceptible (Inqilab 91, Galaxy 2013, and 15BT023) and stripe rust-resistant (NARC 2011, Ujala 2015, TW1410) cultivars were identified and characterized. Abundance of endophytes was found in roots as compared with stems and leaves. Resistant and susceptible cultivars significantly differed in abundance of endophytic bacteria. Restriction analysis of 16S rRNA genes amplified from 100 bacterial isolates produced 17 unique patterns. Representatives of each of the 17 unique patterns were sequenced and identified. Among the sequenced bacteria, 8 belonged to Firmicutes, 7 were Proteobacteria, and 2 were Actinobacteria. Most of the isolates have plant growth-promoting properties and a few have the potential of producing hydrolytic enzymes. Two isolates showed significant inhibition of rust spore germination. These endophytic bacteria not only can be helpful in growth-promoting activities but also can assist in biocontrol of stripe rust disease.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biota , Endófitos/classificação , Endófitos/isolamento & purificação , Doenças das Plantas/microbiologia , Triticum/microbiologia , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Resistência à Doença , Endófitos/genética , Endófitos/crescimento & desenvolvimento , Filogenia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Food Chem Toxicol ; 121: 24-36, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30120946

RESUMO

Bisphenol A an estrogen-mimic endocrine disrupting chemical, used to manufacture polycarbonate plastics and epoxy resins with toxic effects for male reproduction. Due to its toxicity, industries have started to replace it with other bisphenols. In this study, the toxicity of BPA analogues (BPB, BPF and BPS) was evaluated in a chronic study. We investigated whether the chronic exposure to low bisphenols doses affects spermatogenesis with outcomes on oxidative stress and male reproductive system. Male rats (22 day old) were exposed to water containing 0.1% ethanol for control or different concentrations of BPA and its analogues BPB, BPF and BPS (5, 25 and 50 µg/L) in drinking water for 48 weeks. Results of the present study showed a significant alteration in the gonadosomatic index (GSI) and relative reproductive organs weights. Oxidative stress in the testis was significantly elevated while sperm motility, Daily sperm production (DSP) and number of sperm in epididymis were reduced. Plasma testosterone, LH and FSH concentrations were reduced and estradiol levels were high in 50 µg/L exposed group. These results suggest that exposure to BPA and its analogues for chronic duration can induce structural changes in testicular tissue and endocrine alterations in the male reproductive system.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Fenóis/toxicidade , Sulfonas/toxicidade , Testículo/efeitos dos fármacos , Animais , Compostos Benzidrílicos/administração & dosagem , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/administração & dosagem , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Espermatogênese/efeitos dos fármacos , Sulfonas/administração & dosagem , Superóxido Dismutase/metabolismo , Testículo/enzimologia , Testículo/metabolismo , Testosterona/sangue
14.
Sci Rep ; 7(1): 5089, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698641

RESUMO

Xanthomonas oryzae pv. oryzicola (Xoc) and X. oryzae pv. oryzae (Xoo) cause bacterial leaf streak (BLS) and bacterial leaf blight (BLB) in rice, respectively. Unlike Xoo, endogenous avirulence-resistance (avr-R) gene interactions have not been identified in the Xoc-rice pathosystem; however, both pathogens possess transcription activator-like effectors (TALEs) that are known to modulate R or S genes in rice. The transfer of individual tal genes from Xoc RS105 (hypervirulent) into Xoc YNB0-17 (hypovirulent) led to the identification of tal7, which suppressed avrXa7-Xa7 mediated defense in rice containing an Xa7 R gene. Mobility shift and microscale thermophoresis assays showed that Tal7 bound two EBE sites in the promoters of two rice genes, Os09g29100 and Os12g42970, which encode predicted Cyclin-D4-1 and GATA zinc finger family protein, respectively. Assays using designer TALEs and a TALE-free strain of Xoo revealed that Os09g29100 was the biologically relevant target of Tal7. Tal7 activates the expression of rice gene Os09g29100 that suppresses avrXa7-Xa7 mediated defense in Rice. TALEN editing of the Tal7-binding site in the Os09g29100 gene promoter further enhanced resistance to the pathogen Xoc RS105. The suppression of effector-trigger immunity (ETI) is a phenomenon that may contribute to the scarcity of BLS resistant cultivars.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Oryza/genética , Oryza/imunologia , Imunidade Vegetal/genética , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Xanthomonas/metabolismo , Sequência de Bases , Sítios de Ligação , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica
15.
Indian J Endocrinol Metab ; 19(3): 347-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25932388

RESUMO

INTRODUCTION: South Asian population has a particularly high prevalence of thyroid disorders mainly due to iodine deficiency and goitrogen use. There is no data available for prevalence of thyroid disorders in the general population living in nonmountainous regions of Pakistan. MATERIALS AND METHODS: A total of 2335 residents of Pak Pattan, Punjab, Pakistan were interviewed about demographic, dietary, medical and environmental history as well as screened for goiter. Individuals of all ages and either gender were included. RESULTS: Median age was 34 (10-88) years and 1164 (49.9%) were males. Median monthly income was 49 (3.9-137) USD. Six hundred and sixty-nine (28.7%) subjects had palpable goiter. 77.5% (n = 462) and 22.5% (n = 133) had World Health Organization Grade I and Grade II goiters respectively, further screened by measuring thyroid-stimulating hormone (TSH). In subjects with TSH <0.4 mg/dL, free T3 and free T4 levels were measured. In 185 goiter subjects when TSH was measured, 50% (n = 93) were euthyroid, 48% (n = 89) were hyperthyroid, and one subject each was hypothyroid and subclinically hyperthyroid. 29/89 hyperthyroid subjects underwent radionuclide scanning. Twelve subjects had heterogeneous uptake consistent with multinodular goiter, 12 subjects had diffuse uptake, two had cold nodules and two had hyperfunctioning single nodules. Goiter was significantly more common among females, unmarried individuals and individuals drinking tube well (subterranean) water. Goiter was less common among those who consumed daily milk, daily ghee (hydrogenated oil), spices, chilies, and turmeric. DISCUSSION: In our study population, goiter was endemic with very high prevalence of hyperthyroidism. Turmeric use was association with reduced goitrogenesis. Further studies to assess iodine sufficiency, thiocyanate exposure and autoimmunity need to be conducted. Masses consuming high goitrogen diets should be educated to incorporate turmeric, spices and green chilies in their cooking recipes, to reduce the risk of goiter development. In addition, use of iodized salt in their daily diet cannot be overemphasized.

16.
Mol Plant Microbe Interact ; 27(9): 983-95, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25105804

RESUMO

The closely related plant pathogens Xanthomonas oryzae pv. oryzicola and X. oryzae pv. oryzae cause bacterial leaf streak (BLS) and bacterial leaf blight (BLB), respectively, in rice. Unlike X. oryzae pv. oryzae, endogenous avirulence-resistance (avr-R) gene interactions have not been identified in the X. oryzae pv. oryzicola-rice pathosystem, though both X. oryzae pv. oryzicola and X. oryzae pv. oryzae possess transcriptional activator-like effectors (TALE), which are known to modulate R or S genes in rice. In this report, avrXa7, avrXa10, and avrXa27 from X. oryzae pv. oryzae were transferred into YNB0-17 and RS105, hypovirulent and hypervirulent strains, respectively, of X. oryzae pv. oryzicola. When YNB0-17 containing avrXa7, avrXa10, or avrXa27 was inoculated to rice, hypersensitive responses (HR) were elicited in rice cultivars containing the R genes Xa7, Xa10, and Xa27, respectively. By contrast, RS105 expressing avrXa27 elicited an HR in a rice cultivar containing Xa27 but the expression of avrXa7 and avrXa10 in RS105 did not result in HR in rice cultivars containing Xa7 and Xa10, correspondingly. Southern blot analysis demonstrated that YNB0-17 possesses only approximately nine putative tale genes, whereas the hypervirulent RS105 contains at least 20. Although YNB0-17 contains an intact type III secretion system (T3SS), its genome is lacking the T3SS effector genes avrRxo1 and xopO, which are present in RS105. The introduction of avrRxo1 and xopO into YNB0-17 did not suppress avrXa7- or avrXa10-triggered immunity in rice. However, the transference of individual tale genes from RS105 into YNB0-17 led to the identification of tal6 and tal11a that suppressed avrXa7-Xa7-mediated defense. Thus, YNB0-17 may be a useful recipient for discovering such suppressors. This is the first report that co-evolutionally generated tale genes in X. oryzae pv. oryzicola suppress gene-for-gene defense against BLB, which may explain the lack of BLS-resistant cultivars.


Assuntos
Proteínas de Bactérias/genética , Oryza/imunologia , Doenças das Plantas/imunologia , Transativadores/genética , Xanthomonas/patogenicidade , Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos , DNA Bacteriano/genética , Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especificidade da Espécie , Transativadores/metabolismo , Efetores Semelhantes a Ativadores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Virulência , Xanthomonas/genética , Xanthomonas/isolamento & purificação , Xanthomonas/fisiologia
17.
Phytopathology ; 104(7): 672-82, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24423401

RESUMO

Xanthomonas oryzae pv. oryzicola causes bacterial leaf streak (BLS), a devastating disease of rice in Asia countries. X. oryzae pv. oryzicola utilizes repertoires of transcriptional activator-like effectors (TALEs) to manipulate host resistance or susceptibility; thus, TALEs can determine the outcome of BLS. In this report, we studied genetic diversity in putative tale genes of 65 X. oryzae pv. oryzicola strains that originated from nine provinces of southern China. Genomic DNAs from the 65 strains were digested with BamHI and hybridized with an internal fragment of avrXa3, a tale gene originating from the related pathogen, X. oryzae pv. oryzae, which causes bacterial leaf blight (BLB). Southern blot analysis indicated that the strains contained a variable number (9 to 22) of avrXa3-hybridizing fragments (e.g., putative tale genes). Based on the number and size of hybridizing bands, strains were classified into 14 genotypes (designated 1 to 14), and genotypes 3 and 10 represented 29.23 and 24.64% of the total, respectively. A high molecular weight BamHI fragment (HMWB; ≈6.0 kb) was present in 12 of the 14 genotypes, and sequence analysis of the HMWB revealed the presence of a C-terminally truncated tale, an insertion element related to IS1403, and genes encoding phosphoglycerate mutase and endonuclease V. Primers were developed from the 6.0-kb HMWB fragment and showed potential in genotyping X. oryzae pv. oryzicola strains by polymerase chain reaction. Virulence of X. oryzae pv. oryzicola strains was assessed on 23 rice cultivars containing different resistance genes for BLB. The X. oryzae pv. oryzicola strains could be grouped into 14 pathotypes (I to XIV), and the grouping of strains was almost identical to the categories determined by genotypic analysis. In general, strains containing higher numbers of putative tale genes were more virulent on rice than strains containing fewer tales. The results also indicate that there are no gene-for-gene relationships between the tested rice lines and X. oryzae pv. oryzicola strains. To our knowledge, this is the first description of genetic diversity of X. oryzae pv. oryzicola strains based on tale gene analysis.


Assuntos
Proteínas de Bactérias/genética , Variação Genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Xanthomonas/genética , Sequência de Bases , China , Análise por Conglomerados , Primers do DNA/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Epistasia Genética , Genótipo , Dados de Sequência Molecular , Mutação , Hibridização de Ácido Nucleico , Folhas de Planta/microbiologia , Análise de Sequência de DNA , Virulência , Xanthomonas/classificação , Xanthomonas/isolamento & purificação , Xanthomonas/patogenicidade
19.
Mol Plant Pathol ; 14(7): 678-92, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23672717

RESUMO

Xanthomonas oryzae pv. oryzicola (Xoc) is the causal agent of bacterial leaf streak, a devastating disease in rice. Xoc uses a type III secretion (T3S) system, which is encoded by the hrp-hrc-hpa (hypersensitive response and pathogenicity, hrp-conserved and hrp-associated) genes, to inject repertoires of T3S effectors (T3Es) into plant cells. Many of the hrp-hrc-hpa genes have roles in pathogenesis, but the role of hrpE3, which shows homology to hpaE in X. campestris pv. vesicatoria (Xcv), is poorly understood. In this study, hrpE3 was shown to be transcribed independent of the hrpD operon, and its expression was dependent on a promoter within hpaB. The expression of hrpE3 was positively regulated by HrpG and HrpX, a finding probably caused by an imperfect plant-inducible promoter (PIP) box (TTCGT-N16 -TTCGA) in the hrpE3 promoter. The secretion of HrpE3 was dependent on T3S, and subcellular localization of HrpE3 was cytoplasmic and nuclear in plant cells. A mutation in hrpE3 reduced the virulence of Xoc by decreasing disease lesion length and bacterial growth in planta. Full virulence was restored to the mutant when Xoc hrpE3, but not Xcv hpaE, was expressed in trans. The differences in transcription, secretion via the T3S system and bacterial virulence in plants were attributed to N-terminal amino acid differences between Xoc HrpE3 and Xcv HpaE. Collectively, the results demonstrate that hrpE3 encodes a T3E protein which is delivered into the plant cell through the T3S system, localizes to the cytoplasm and nucleus, and is required for full virulence in rice.


Assuntos
Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos , Oryza/microbiologia , Xanthomonas/patogenicidade , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sequência de Bases , Citoplasma/metabolismo , Regulação Bacteriana da Expressão Gênica , Interações Hospedeiro-Patógeno , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Transporte Proteico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Frações Subcelulares/metabolismo , Transcrição Gênica , Virulência/genética , Xanthomonas/genética , Xanthomonas/crescimento & desenvolvimento
20.
PLoS One ; 8(2): e56240, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23418541

RESUMO

Harpins are produced by gram-negative phytopathogenic bacteria and typically elicit hypersensitive response (HR) in non-host plants. The characterization of harpins in Xanthomonas species is largely unexplored. Here we demonstrate that Xanthomonas produce a highly conserved single-stranded DNA-binding protein (SSB(X)) that elicits HR in tobacco as by harpin Hpa1. SSB(X), like Hpa1, is an acidic, glycine-rich, heat-stable protein that lacks cysteine residues. SSB(X)-triggered HR in tobacco, as by Hpa1, is characterized by the oxidative burst, the expression of HR markers (HIN1, HSR203J), pathogenesis-related genes, and callose deposition. Both SSB(X)- and Hpa1-induced HRs can be inhibited by general metabolism inhibitors actinomycin D, cycloheximide, and lanthanum chloride. Furthermore, those HRs activate the expression of BAK1 and BIK1 genes that are essential for induction of mitogen-activated protein kinase (MAPK) and salicylic acid pathways. Once applied to plants, SSB(X) induces resistance to the fungal pathogen Alternaria alternata and enhances plant growth. When ssb(X)was deleted in X. oryzae pv. oryzicola, the causal agent of bacterial leaf streak in rice, the resulting ssb(Xoc)mutant was reduced in virulence and bacterial growth in planta, but retained its ability to trigger HR in tobacco. Interestingly, ssb(Xoc)contains an imperfect PIP-box (plant-inducible promoter) and the expression of ssb(Xoc)is regulated by HrpX, which belongs to the AraC family of transcriptional activators. Immunoblotting evidence showed that SSB(x) secretion requires a functional type-III secretion system as Hpa1 does. This is the first report demonstrating that Xanthomonas produce a highly-conserved SSB(X) that functions as a harpin-like protein for plant immunity.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Xanthomonas/genética , Alternaria/fisiologia , Proteínas de Bactérias/metabolismo , Sequência de Bases , Western Blotting , Sequência Conservada/genética , Proteínas de Ligação a DNA/metabolismo , Glucanos/metabolismo , Microscopia de Fluorescência , Dados de Sequência Molecular , Mutação , Oryza/citologia , Oryza/genética , Oryza/microbiologia , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Folhas de Planta/citologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Plantas Geneticamente Modificadas , Homologia de Sequência de Aminoácidos , /microbiologia , Virulência/genética , Xanthomonas/metabolismo , Xanthomonas/patogenicidade
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