77 resultados para ANTIVIRAL
Resumo:
Dengue is the most important arboviral disease in the world. As chloroquine, an antimalarial agent, has shown some antiviral effects, this study evaluated its effect in patients with dengue. A randomised, double-blind study was performed by administering chloroquine or placebo for three days to 129 patients with dengue-related symptoms. Of these patients, 37 were confirmed as having dengue and completed the study; in total, 19 dengue patients received chloroquine and 18 received placebo. There was no significant difference in the duration of the disease or the degree and days of fever. However, 12 patients (63%) with confirmed dengue reported a substantial decrease in pain intensity and a great improvement in their ability to perform daily activities (p = 0.0004) while on the medication and the symptoms returned immediately after these patients stopped taking the medication. The same effect was not observed in patients with diseases other than dengue. Therefore, this study shows that patients with dengue treated with chloroquine had an improvement in their quality of life and were able to resume their daily activities. However, as chloroquine did not alter the duration of the disease or the intensity and days of fever, further studies are necessary to confirm the clinical effects and to assess the side effects of chloroquine in dengue patients.
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Inter-individual heterogeneity in the response to human T-lymphotropic virus 1 (HTLV-1) infection has been partially attributed to host genetic background. The antiviral activity of the inflammasome cytoplasmic complex recognises viral molecular patterns and regulates immune responses via the activation of interleukin (IL)-1 family (IL-1, IL-18 and IL-33) members. The association between polymorphisms in the inflammasome receptors NLRP1 and NLRP3 and HTLV-1 infection was evaluated in a northeastern Brazilian population (84 HTLV-1 carriers and 155 healthy controls). NLRP3 rs10754558 G/G was associated with protection against HTLV-1 infection (p = 0.012; odds ratio = 0.37). rs10754558 affects NLRP3 mRNA stability; therefore, our results suggest that higher NLRP3 expression may augment first-line defences, leading to the effective protection against HTLV-1 infection.
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Lactotransferrin, also known as lactoferrin, is an iron binding glycoprotein that displays antiviral activity against many different infectious agents, including human immunodeficiency virus (HIV)-1. Lactotransferrin is present in the breast milk and in the female genitourinary mucosa and it has been hypothesised as a possible candidate to prevent mother-to-child HIV-1 transmission. To verify if two functional polymorphisms, Thr29Ala and Arg47Lys, in the lactotransferrin encoding gene (LTF) could affect HIV-1 infection and vertical transmission, a preliminary association study was performed in 238 HIV-1 positive and 99 HIV-1 negative children from Brazil, Italy, Africa and India. No statistically significant association for the Thr29Ala and Arg47Lys LTF polymorphisms and HIV-1 susceptibility in the studied populations was found. Additionally LTF polymorphisms frequencies were compared between the four different ethnic groups.
Resumo:
Abstract OBJECTIVE Comparing Health-Related Quality of Life (HRQoL) scores in patients with chronic hepatitis C undergoing double and triple antiviral therapy and analyzing possible factors related to HRQoL. METHOD HRQoL was assessed using the Short Form 36 and Chronic Liver Disease Questionnaire, which were applied at baseline and at weeks 4, 12 and 16 of treatment to 32 patients divided into two groups: double therapy with pegylated interferon (IFN-PEG) and ribavirin, and triple therapy with PEG-IFN, ribavirin and telaprevir. RESULTS The reduction of HRQoL was greater in patients receiving triple therapy compared to those treated with two drugs, the most critical time is at 12 weeks in both groups. After removal of telaprevir, the triple therapy group significantly improved their HRQoL scores. Anxiety and depression before treatment, employment status and race are significantly related to diminished HRQoL. CONCLUSION Patients undergoing double and triple therapy have diminished HRQoL indexes, but the addition of telaprevir chooses a more significant decrease.
Resumo:
O objetivo deste trabalho foi avaliar a proteção antiviral específica via RNA de interferência (RNAi) contra o vírus da síndrome da mancha-branca (WSSV), em camarões marinhos (Litopenaeus vannamei). Os camarões foram injetados com uma sequência dsRNA específica (vp28 do envelope viral), seguida por desafio com WSSV após 48 horas. Avaliaram-se o hemograma às 0, 3, 6, 24, 48 e 72 horas após o desafio, e a taxa de mortalidade durante 30 dias. Nos animais tratados com dsRNA vp28, a infecção viral foi limitada, e a sobrevivência (73%) e a "clearance" viral (80%) foram maiores do que nos camarões infectados, não tratados, que apresentaram 100% de mortalidade em cinco dias. Nos camarões tratados com dsRNA, o hemograma diminuiu até 6 horas após o desafio, seguido por aumento, tendo atingido o nível normal em 72 horas. O tratamento com dsRNA vp28 limita a infecção nos camarões por WSSV, restaura as suas condições imunológicas e promove "clearance" viral na maioria dos sobreviventes. Esses resultados são indicativos de que dsRNA vp28 pode servir como ferramenta molecular para combater o WSSV e que o RNAi representa abordagem promissora para controlar doenças virais em camarões cultivados.
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This work describes the more promising chemical and pharmacological or biological results obtained with some selected Brazilian medicinal plants, which has been conducted at Núcleo de Investigações Químico-Farmacêuticas (NIQFAR)/UNIVALI in the last five years. It was found that several phytoconstituents exhibit different activities, such as antispasmodic, antiallergic, analgesic, antiinflammatory, antimicrobial and antiviral. Some of them were more potent than some well-known standard drugs used clinically.
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The number of agents available for the treatment of viral infections has increased dramatically during the past decade most of them belonging to the nucleoside class. The accomplishment of many syntheses for these nucleosides in recent years offers evidence that the field is very important for the organic synthesis. The discussion of several approaches for preparing deoxy and dehydronucleosides is reviewed in a simplified way.
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This article shows that thiosemicarbazones, semicarbazones and their metal complexes can exhibit target selectivity along with a wide pharmacological profile. Complexes of thiosemicarbazones with cytotoxic or antitumoral activity are presented, some of which show activity against cisplatinum-resistant cells. The inhibition mechanism of the enzyme ribonucleoside diphosphate reductase (RDR), involved in DNA syntheses, by alpha(N)-heterocyclic thiosemicarbazones is discussed. The encouraging results of clinical trials with the RDR inhibitor 3-aminopyridine-2-carboxaldehyde thiosemicarbazone ("Triapine") against rapidly growing tumors are outlined. Examples are also given of thiosemicarbazones with antiviral and antimicrobial activity. The possible applications of semicarbazones as anticonvulsants with low toxicity and good therapeutic index are presented.
Resumo:
Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry.
Resumo:
Zidovudine (AZT) and stavudine (D4T) are nucleoside reverse transcriptase inhibitors extensively used in human immunodeficiency virus (HIV) infected patients. In order to evaluate the quality of these drugs, two stability indicating HPLC methods were developed. The validated methods were applied in quantitative determination of AZT, D4T and their induced degradation products in capsule preparations. The stability studies were conducted at controlled temperature and relative humidity conditions based on the International Conference on Harmonization stability studies protocol for Zone IV areas. Easy sample preparation and low-cost make these methods especially useful for quality control and stability studies of AZT and D4T in drug products.
Resumo:
Species of Cassia are widely distributed in tropical and subtropical regions throughout the world, and have been extensively investigated chemically and pharmacologically.They are known to be a rich source of phenolic derivatives, most of them with important biological and pharmacological properties. Some Asian, African and Indian tribes use these species as a laxative, purgative, antimicrobial, antipyretic, antiviral and anti-inflammatory agent. Among a number of other classes of secondary metabolites, such as anthracene derivatives, antraquinones, steroids and stilbenoids, biologically active piperidine alkaloids are an especially important bioactive class of compounds that showed to be restricted to a small group of Cassia species. In this paper we present an overview of the chemical, biological and ethnopharmacological data on Cassia piblished in the literature.
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Microbiológica is a science-based Brazilian Company with its core competence focused on nucleoside process chemistry. This article describes its origin and contributions as well as comments on public policies which impact the Brazilian industrial development.
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The AIDS epidemy has spread out and led to the diversification on the research for new antiviral drugs. Natural products, especially those derived from plants, are well-recognized as excellent sources of new drugs. Several of them have inhibitory activity against HIV replication, and some have been already clinically tested, with favorable results. This review presents the biochemical basis of the viral cycle and the research up to date on the identification, determination of the mechanism of biological action together with the therapeutical potential of plants-derived natural products, in the inhibition of HIV.
Resumo:
Turmeric, obtained from the dried rhizomes of Curcuma longa (Zingiberaceae), is a golden colored material, commonly used around the world for seasoning and coloring food dishes. Since antiquity, turmeric has been widely used in the treatment of several diseases in traditional Chinese and Indian medicine (Ayurveda), where it is also known by other names such as Kanchani (goddess gold) or also Gauri (having a bright and luminous face), a designation stemming from the gilded appearance of the plant material. Curcumin, the main chemical component of turmeric, is responsible both for its properties as dyes as well as its biological activities. This diarylheptanoid was first isolated almost two centuries ago and had its chemical structure determined in 1910 as being diferuloylmethane. Subsequently, more detailed and relevant data were obtained furthering the understanding of structural features of curcumin. The classical methodology for the synthesis of curcumin and other curcuminoids was described in 1960 by Pabon. Subsequently, different variations on this methodology have been developed, culminating with the synthesis of different curcuminoids. Several studies have been published in recent years on the biological activities exhibited by curcumin including its antioxidant, antitumor, anti-inflammatory, antiviral, antibacterial, antifungal, antimalarial and leishmanicidal activities.
Resumo:
Um isolado do Sugarcane mosaic virus (SCMV) causando sintomas de mosaico em plantas de cana-de-açúcar do clone RB925268 foi identificado no estado do Paraná. Gemas axilares extraídas de colmos infectados, medindo de 4 a 8 mm, foram utilizadas como explantes e regeneradas em plântulas em meio de cultura MS, suplementado ou não com o antiviral ribavirina, nas concentrações variando de 10-60 mg/L. O efeito fitotóxico da ribavirina foi constatado, resultando na morte dos explantes em concentrações iguais ou superiores a 30 mg/L. Após seis meses de aclimatação das plantas em estufa plástica, o vírus não foi detectado nas plantas provenientes do meio MS contendo ribavirina na concentração de 25 mg/L, confirmado através dos ensaios de inoculação mecânica em sorgo 'Rio' e de RT-PCR.