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1.
Braz. j. biol ; 82: 1-11, 2022. tab, ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468549

ABSTRACT

Vegetables are an important source of income and high-value crops for small farmers. Chilli (Capsicum spp.) is one of the most economically important vegetables of Pakistan and it is grown throughout the country. It is a rich source of nutrition especially vitamins A, B, C and E along with minerals as folic acid, manganese (Mn), potassium (K) and molybdenum (Mo). Chilli possesses seven times more amount of vitamin C than an orange. Vitamin A, C and beta carotenoids are strong antioxidants to scavenge the free radicals. Chilli production is restricted due to various biotic factors. Among these viruses, Chilli veinal mottle virus (ChiVMV) is one of the most destructive and menacing agents that inflicts heavy and colossal losses that accounted for 50% yield loss both in quality and quantity. Pathogen-Derived Resistance (PDR) approach is considered one of the effective approaches to manage plant viruses. In this study, ChiVMV was characterized on a molecular level, the coat protein (CP) gene of the virus was stably transformed into Nicotiana benthamiana plants using Agrobacterium tumefaciens. The transgenic plants were challenged with the virus to evaluate the level of resistance of plants against the virus. It was observed that the plants expressing CP gene have partial resistance against the virus in terms of symptoms' development and virus accumulation. Translation of this technique into elite chilli varieties will be resulted to mitigate the ChiVMV in the crop as well as an economic benefit to the farmers.


Vegetais são uma importante fonte de renda e culturas de alto valor para os pequenos agricultores. A pimenta-malagueta (Capsicum spp.) é uma das hortaliças mais importantes economicamente do Paquistão e é cultivada em todo o país. É uma rica fonte de nutrição, especialmente vitaminas A, B, C e E com minerais como ácido fólico, manganês (Mn), potássio (K) e molibdênio (Mo). O pimentão possui sete vezes mais vitamina C do que a laranja. Vitaminas A e C e betacarotenoides são antioxidantes fortes para eliminar os radicais livres. A produção de pimenta é restrita devido a vários fatores bióticos. Entre esses vírus, o ChiVMV é o agente mais destrutivo e ameaçador que inflige perdas pesadas e colossais que representam 50% da perda de rendimento, tanto em qualidade quanto em quantidade. A abordagem de resistência derivada de patógenos (PDR) é considerada uma das abordagens eficazes para gerenciar os vírus de plantas. Neste estudo, ChiVMV foi caracterizado em nível molecular e o gene CP do vírus foi transformado de forma estável em plantas Nicotiana benthamiana usando Agrobacterium tumefaciens. As plantas transgênicas foram desafiadas com o vírus para avaliar seu nível de resistência contra o vírus. Observou-se que as plantas que expressam o gene CP apresentam resistência parcial ao vírus em termos de desenvolvimento de sintomas e acúmulo de vírus. A tradução dessa técnica em variedades de pimenta de elite resultará na mitigação do ChiVMV na safra, bem como em benefícios econômicos para os agricultores em termos de melhor rendimento e baixo custo de produção.


Subject(s)
Capsicum/virology , Drug Resistance, Viral , Plants, Genetically Modified , Tobacco/genetics
2.
Braz. j. biol ; 822022.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468736

ABSTRACT

Abstract Vegetables are an important source of income and high-value crops for small farmers. Chilli (Capsicum spp.) is one of the most economically important vegetables of Pakistan and it is grown throughout the country. It is a rich source of nutrition especially vitamins A, B, C and E along with minerals as folic acid, manganese (Mn), potassium (K) and molybdenum (Mo). Chilli possesses seven times more amount of vitamin C than an orange. Vitamin A, C and beta-carotenoids are strong antioxidants to scavenge the free radicals. Chilli production is restricted due to various biotic factors. Among these viruses, Chilli veinal mottle virus (ChiVMV) is one of the most destructive and menacing agents that inflicts heavy and colossal losses that accounted for 50% yield loss both in quality and quantity. Pathogen-Derived Resistance (PDR) approach is considered one of the effective approaches to manage plant viruses. In this study, ChiVMV was characterized on a molecular level, the coat protein (CP) gene of the virus was stably transformed into Nicotiana benthamiana plants using Agrobacterium tumefaciens. The transgenic plants were challenged with the virus to evaluate the level of resistance of plants against the virus. It was observed that the plants expressing CP gene have partial resistance against the virus in terms of symptoms development and virus accumulation. Translation of this technique into elite chilli varieties will be resulted to mitigate the ChiVMV in the crop as well as an economic benefit to the farmers.


Resumo Vegetais são uma importante fonte de renda e culturas de alto valor para os pequenos agricultores. A pimenta-malagueta (Capsicum spp.) é uma das hortaliças mais importantes economicamente do Paquistão e é cultivada em todo o país. É uma rica fonte de nutrição, especialmente vitaminas A, B, C e E com minerais como ácido fólico, manganês (Mn), potássio (K) e molibdênio (Mo). O pimentão possui sete vezes mais vitamina C do que a laranja. Vitaminas A e C e betacarotenoides são antioxidantes fortes para eliminar os radicais livres. A produção de pimenta é restrita devido a vários fatores bióticos. Entre esses vírus, o ChiVMV é o agente mais destrutivo e ameaçador que inflige perdas pesadas e colossais que representam 50% da perda de rendimento, tanto em qualidade quanto em quantidade. A abordagem de resistência derivada de patógenos (PDR) é considerada uma das abordagens eficazes para gerenciar os vírus de plantas. Neste estudo, ChiVMV foi caracterizado em nível molecular e o gene CP do vírus foi transformado de forma estável em plantas Nicotiana benthamiana usando Agrobacterium tumefaciens. As plantas transgênicas foram desafiadas com o vírus para avaliar seu nível de resistência contra o vírus. Observou-se que as plantas que expressam o gene CP apresentam resistência parcial ao vírus em termos de desenvolvimento de sintomas e acúmulo de vírus. A tradução dessa técnica em variedades de pimenta de elite resultará na mitigação do ChiVMV na safra, bem como em benefícios econômicos para os agricultores em termos de melhor rendimento e baixo custo de produção.

3.
Braz. j. biol ; 82: e243692, 2022. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1278520

ABSTRACT

Vegetables are an important source of income and high-value crops for small farmers. Chilli (Capsicum spp.) is one of the most economically important vegetables of Pakistan and it is grown throughout the country. It is a rich source of nutrition especially vitamins A, B, C and E along with minerals as folic acid, manganese (Mn), potassium (K) and molybdenum (Mo). Chilli possesses seven times more amount of vitamin C than an orange. Vitamin A, C and betacarotenoids are strong antioxidants to scavenge the free radicals. Chilli production is restricted due to various biotic factors. Among these viruses, Chilli veinal mottle virus (ChiVMV) is one of the most destructive and menacing agents that inflicts heavy and colossal losses that accounted for 50% yield loss both in quality and quantity. Pathogen-Derived Resistance (PDR) approach is considered one of the effective approaches to manage plant viruses. In this study, ChiVMV was characterized on a molecular level, the coat protein (CP) gene of the virus was stably transformed into Nicotiana benthamiana plants using Agrobacterium tumefaciens. The transgenic plants were challenged with the virus to evaluate the level of resistance of plants against the virus. It was observed that the plants expressing CP gene have partial resistance against the virus in terms of symptoms' development and virus accumulation. Translation of this technique into elite chilli varieties will be resulted to mitigate the ChiVMV in the crop as well as an economic benefit to the farmers.


Vegetais são uma importante fonte de renda e culturas de alto valor para os pequenos agricultores. A pimenta-malagueta (Capsicum spp.) é uma das hortaliças mais importantes economicamente do Paquistão e é cultivada em todo o país. É uma rica fonte de nutrição, especialmente vitaminas A, B, C e E com minerais como ácido fólico, manganês (Mn), potássio (K) e molibdênio (Mo). O pimentão possui sete vezes mais vitamina C do que a laranja. Vitaminas A e C e betacarotenoides são antioxidantes fortes para eliminar os radicais livres. A produção de pimenta é restrita devido a vários fatores bióticos. Entre esses vírus, o ChiVMV é o agente mais destrutivo e ameaçador que inflige perdas pesadas e colossais que representam 50% da perda de rendimento, tanto em qualidade quanto em quantidade. A abordagem de resistência derivada de patógenos (PDR) é considerada uma das abordagens eficazes para gerenciar os vírus de plantas. Neste estudo, ChiVMV foi caracterizado em nível molecular e o gene CP do vírus foi transformado de forma estável em plantas Nicotiana benthamiana usando Agrobacterium tumefaciens. As plantas transgênicas foram desafiadas com o vírus para avaliar seu nível de resistência contra o vírus. Observou-se que as plantas que expressam o gene CP apresentam resistência parcial ao vírus em termos de desenvolvimento de sintomas e acúmulo de vírus. A tradução dessa técnica em variedades de pimenta de elite resultará na mitigação do ChiVMV na safra, bem como em benefícios econômicos para os agricultores em termos de melhor rendimento e baixo custo de produção.


Subject(s)
Tobacco/genetics , Potyvirus/genetics , Pakistan , Plant Diseases/genetics , Plants, Genetically Modified/genetics , Disease Resistance
4.
Medicina (B.Aires) ; 81(3): 421-426, jun. 2021. graf
Article in Spanish | LILACS | ID: biblio-1346479

ABSTRACT

Resumen Los virus ARN, excepto los retrovirus, se replican por acción de una ARN polimerasa ARN-dependiente que carece de exonucleasa correctora y, en consecuencia, en cada replicación puede co meter errores. Así se originan mutantes que, según su menor o mayor fitness, se extinguen o bien prosperan y originan variantes que escapan al sistema inmune. Las mutaciones de SARS-CoV-2 más importantes son las que alteran la proteína viral S, porque ella tiene la llave de ingreso del virus a la célula humana. Cuanto más se replican los virus, más mutan, y se hace más probable que aparezcan variantes resistentes dominantes. En esos casos, se requerirá una aplicación más estricta de las medidas de protección de la comunidad. Las vacunas y los anticuerpos policlonales, que inducen una respuesta dirigida hacia toda la proteína S, mantendrían protec ción efectiva contra las variantes del SARS-CoV-2. Además, las vacunas inducirían una mayor respuesta de células T helper y citotóxicas, lo que puede ser un biomarcador de protección. En áreas densamente pobladas con escasas medidas de protección, el virus se difunde libremente y aumenta la probabilidad de mutaciones de escape. India y Manaos ejemplifican esa situación. La evolución natural selecciona las mutantes que se repro ducen con mayor eficiencia sin eliminar al huésped, lo que facilita la propagación. En cambio, la circulación de virus de alta virulencia y letalidad (Ebola, hantavirus), que eliminan al huésped, se circunscribe a determinadas áreas geográficas, sin mayor difusión. Por lo tanto, sería esperable que SARS-CoV-2 evolucione a variantes más infecciosas y menos virulentas.


Abstract RNA viruses (except retroviruses) replicate by the action of an RNA-dependent RNA polymerase, which lacks a proofreading exo nuclease and, consequently, errors may occur in each replication giving place to viral mutants. Depending on their fitness, these mutants either become extinct or thrive, spawning variants that escape the immune system. The most important SARS-CoV-2 mutations are those that alter the amino acid sequence in the viral S protein because this protein holds the key for the virus to enter the human cell. The more viruses replicate, the more they mutate, and the more likely it is that dominant resistant variants will appear. In such cases, more stringent measures for community protection will be required. Vaccines and polyclonal antibodies, which induce a response directed towards several sites along the S protein, would maintain effective protection against SARS-CoV-2 vari ants. Furthermore, vaccines appear to induce an increased helper and cytotoxic T-cell response, which may also be a biomarker of protection. In densely populated areas with insufficient protection measures, the virus spreads freely, thus increasing the likelihood of generating escape mutants. India and Manaus exemplify this situation. Natural evolution selects the mutants that multiply most efficiently without eliminating the host, thus facilitating their spread. Contrastingly, the circulation of viruses of high virulence and lethality (Ebola, hantavirus) that elimi nate the host remain limited to certain geographic areas, without further dissemination. Therefore, it would be expected that SARS-CoV-2 will evolve into more infectious and less virulent variants.


Subject(s)
Humans , Vaccines , COVID-19 , Virus Replication , SARS-CoV-2
5.
Braz. j. infect. dis ; 20(2): 173-178, Mar.-Apr. 2016. tab
Article in English | LILACS | ID: lil-780801

ABSTRACT

Abstract Objective There are a lot of disagreements in the studies on hepatitis B virus (HBV) DNA polymerase mutation rate associated with nucleos(t)ide analogues (NAs) in treatment-naive chronic hepatitis B (CHB) patients. This is the first study aimed to investigate the prevalence of spontaneous HBV resistance mutations in Central China. Methods This study included treatment-naive patients with CHB from June 2012 to May 2015 receiving care at the Institute of Liver Disease in Central China. All patients completed a questionnaire covering different aspects, such as family medical history, course of liver disease, medication history, alcohol use, among others. Mutations in HBV DNA polymerase associated with NAs resistance were detected using INNO-LiPA assay. Results 269 patients were infected with HBV genotype B (81.4%), C (17.9%), and both B and C (0.7%). Mutations in HBV DNA polymerase were detected in 24 patients (8.9%) including rtM204I/V (n = 6), rtN236T (n = 5), rtM250V (n = 2), rtL180M (n = 2), rtT184G (n = 1), rtM207I (n = 1), rtS202I (n = 1), rtM204V/I & rtL180M (n = 5), and rtM204I & rtM250V (n = 1). Conclusion Spontaneous HBV resistance mutations in HBV DNA polymerase were found in treatment-naive patients with CHB in Central China. These findings suggest that we should analyze HBV DNA polymerase resistance mutation associated with NAs before giving antiviral therapy such as lamivudine (LAM), adefovir (ADV), and telbivudine (LdT).


Subject(s)
Humans , Male , Female , Pregnancy , Adult , Middle Aged , Aged , Young Adult , DNA, Viral/genetics , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Drug Resistance, Viral/genetics , DNA-Directed DNA Polymerase/genetics , Mutation/genetics , Antiviral Agents/therapeutic use , China , Hepatitis B virus/drug effects , Prevalence , Prospective Studies , Hepatitis B, Chronic/drug therapy , Genotype
6.
Fortaleza; s.n; 2016. 105 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: biblio-971945

ABSTRACT

A terapia antirretroviraltemporobjetivodiminuiramorbidadeemortalidadedaspessoascomHIV/AIDS,melhorandoaqualidadeeaexpectativadevida. Paradoxalmente, o tratamento irregular pode favorecer a seleçãode variantes resistentes, representandouma das principais causas de falha terapêutica. Tais cepas resistentes podem ser transmitidas a outros indivíduos(resistência transmitida), predispondo àfalha precoce do tratamento inaugural. Ostestesderesistência,principalmenteagenotipagem,permitemadetecçãodemutaçõesdogenomaviral.OobjetivodesteestudofoicaracterizarasmutaçõesderesistênciatransmitidadoHIV-1aosantirretroviraisempacientesrecém-diagnosticadosnoCentro de Testagem e Aconselhamento (CTA) de Fortaleza.Duranteoperíododeoutubrode2013asetembrode2014,foramrecrutadospacientescomtestereagente para oHIVrealizadono CTA. Foram colhidas amostras para realizaçãode quantificação da cargaviral(AbbottRealTime),contagemdelinfócitos CD4+(FACSCaliburBD)egenotipagemHIV-1(TruGeneSiemens).As sequências genéticasforam alinhadas pelo programa MEGA eBioEdit. Ossubtipos do vírus HIV-1 foram determinados e identificados empregando análises no banco de dados do REGA HIV Subtyping Tool. A análisedas mutações de resistência aos antirretrovirais foi realizada utilizando o algoritmo da Universidade de Stanford(HIVdbProgram)e as mutaçõesderesistênciatransmitidaforamidentificadasempregandoaCalibraçãodeResistênciaPopulacional.Foram obtidas amostras biológicas de 108 pacientes, sendo que em 105delas foi possível realizar a reação de sequenciamentoea avaliação quantoàpresençademutaçõesderesistênciaassociadasaos antirretrovirais...


Antiretroviral therapy aims to reduce morbidity and mortality of people with HIV / AIDS, improving the quality and life expectancy. Paradoxically, the irregular treatment may favor the selection of resistant variants, representing a major cause of treatment failure. Such resistant strains can be transmitted to other individuals (transmitted resistance) predisposing to early failure of the inaugural treatment. Resistance tests, particularly genotyping, allow mutation detection in the viral genome. Theaim of this study was to characterize the transmitted resistance HIV-1 mutations to antiretroviral drugs in newly diagnosed patients in the Counseling and Testing Center (CTC) in Fortaleza. During the period October 2013 to September 2014, patients with reagent test for HIV were recruited at CTC. Samples for viral load quantitation (Abbott RealTime), CD4 lymphocytes count (BD FACSCalibur) and HIV-1 genotyping (TRUGENE Siemens), were collected. Genetic sequences were aligned by MEGA and BioEdit program. Thesubtypes of HIV-1 were determined and identified using analysis in REGA HIV subtyping Tool database. The analysis of the antiretroviral resistance mutation was performed using the algorithm of Stanford University (HIVdb Program) and transmitted mutation resistance was identified using the CalibratedPopulationResistance (CPR). Biological samples were obtained from 108 patients, among which in 105 was possible to perform the sequencing reaction and evaluation for the presence of mutations to conferantiretroviral drugresistance...


Subject(s)
Humans , Antiretroviral Therapy, Highly Active , Drug Resistance, Viral , Mutation , Genetic Variation
7.
Chinese Pharmaceutical Journal ; (24): 1265-1269, 2016.
Article in Chinese | WPRIM | ID: wpr-859014

ABSTRACT

Recently, the therapy of hepatitis C virus (HCV) infection, especially with the direct-acting antiviral agents (DAAs), has achieved many progresses. Although it is expected to cure HCV infection completely in the coming future, long-term application of DAAs will inevitably induce virus resistance, resulting in treatment failure. To solve this key problem, development of host-targeting agents (HTAs) emerges as one of effective strategies. HTAs targets the essential host factors for various stages of HCV life cycle, and thus has several advantages against HCV with reducing viral resistance, pan-genotypic antivirus, synergistic antiviral effects combined with known DAAs and decreasing side effects of drugs. This review summarized the recent progress of investigating HTAs in the preclinical and clinical study, to provide clues for the development of new anti-HCV drugs.

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