Información para afectados por el VIH

Se trata de un protocolo que indica detalladamente cómo informar a aquellos pacientes seropositivos -infectados por el virus de la inmunodeficiencia humana- y a los que están desarrollando la enfermedad. se contempla la información pre-prueba, post-prueba, los consejos para mantenerse en salud en caso de infección, y cómo mejorar la calidad de vida en el proceso de la enfermedad.

Información para afectados por el VIH

Se trata de un protocolo que indica detalladamente cómo informar a aquellos pacientes seropositivos -infectados por el virus de la inmunodeficiencia humana- y a los que están desarrollando la enfermedad. se contempla la información pre-prueba, post-prueba, los consejos para mantenerse en salud en caso de infección, y cómo mejorar la calidad de vida en el proceso de la enfermedad.

Hemocidinas derivadas da hemoglobina: estruturas, propriedades e perspectivas

The increasing incidence of microbial infections, high toxicity, and high level of resistance associated with conventional antibiotics has created a need for new drugs. Antimicrobial peptides (AMPs) constitute a promising alternative and/or an important source of knowledge given their ability to inhibit the growth and/or to kill bacteria, fungi, parasites and/or viruses through mechanisms of action different from those of non-peptide drugs. This review focused on this important class of organic compounds that includes hemocidins resulting from hemoglobin proteolysis in vivo and in vitro or from chemical synthesis, subject of research in foreign and Brazilian laboratories.

Tietokonevirusten genealogiaa

Kirjallisuusarvostelu

Proteases virais: importantes alvos terapêuticos de compostos peptideomiméticos

Proteases catalyze the hydrolysis of peptide bonds of proteins and peptides to produce smaller peptides and free amino acids. These enzymes are involved in physiologic processes such as blood coagulation and cellular death, and are related to life cycle of several viruses, such as hepatitis C, dengue, and AIDS. These features make most of proteases very important therapeutic targets for new pharmaceutical compounds. The development of peptidemimetics with improved pharmacokinetic properties is driving extensive research in the field of viral protease inhibitors. The present paper aims to highlight the design and synthesis of peptidemimetics that are able to inhibit viral proteases related to hepatitis C, dengue, and AIDS.

Tietokonevirusten mediaekologiaa

Kirjallisuusarvostelu

APLICAÇÃO DE ÓXIDOS DE FERRO NANOESTRUTURADOS COMO ADSORVENTES E FOTOCATALISADORES NA REMOÇÃO DE POLUENTES DE ÁGUAS RESIDUAIS

New techniques for treating wastewater, particularly the removal or degradation of organic pollutants and heavy metals, among other pollutants, have been extensively studied. The use of nanostructured iron oxides as adsorbent and photocatalyst for the removal of these contaminants has proved a promising approach, not only because of their high treatment efficiency, but also for their cost-effectiveness, having the flexibility for in situ and ex situ applications. In this review, we briefly introduced the most used kinds of iron oxide nanoparticles, some synthesis techniques for iron oxide nanostructure formation, their potential benefits in environmental clean-up, and their recent advances and applications in wastewater treatment. These advances range from the direct applications of synthesized nanoparticles as adsorbents for removing toxic contaminants or as catalysts to oxidize and break down noxious contaminants (including bacteria and viruses) in wastewater, to integrating nanoparticles into conventional treatment technologies, such as composite photocatalytic filters (membranes, sand and ceramic) that combine separation technology with photocatalytic activity. Finally, the impact of nanoparticles on the environment and human health is briefly discussed.

RT-PCR and Dot Blot hybridization methods for a universal detection of tospoviruses

Transcriptase reverse - polymerase chain reaction (RT-PCR) and dot blot hybridization with digoxigenin-labeled probes were applied for the universal detection of Tospovirus species. The virus species tested were Tomato spotted wilt virus, Tomato chlorotic spot virus, Groundnut ringspot virus, Chrysanthemum stem necrosis virus, Impatiens necrotic spot virus, Zucchini lethal chlorosis virus, Iris yellow spot virus. Primers for PCR amplification were designed to match conserved regions of the tospovirus genome. RT-PCR using distinct primer combinations was unable to simultaneously amplify all tospovirus species and consistently failed to detect ZLCV and IYSV in total RNA extracts. However, all tospovirus species were detected by RT-PCR when viral RNA was used as template. RNA-specific PCR products were used as probes for dot hybridization. This assay with a M probe (directed to the G1/G2 gene) detected at low stringency conditions all Tospovirus species, except IYSV. At low stringency conditions, the L non-radioactive probe detected the seven Tospovirus species in a single assay. This method for broad spectrum detection can be potentially employed in quarantine services for indexing in vitro germplasm.

Garlic viral complex: identification of Potyviruses and Carlavirus in Central Brazil

Garlic viruses often occur in complex infections in nature. In this study, a garlic virus complex, collected in fields in Brazil, was purified. RT-PCR was performed using specific primers designed from the consensus regions of the coat protein genes of Onion yellow dwarf virus, a garlic strain (OYDV-G) and Leek yellow stripe virus (LYSV). cDNA of Garlic common latent virus (GCLV) was synthesized using oligo-dT and random primers. By these procedures individual garlic virus genomes were isolated and sequenced. The nucleotide sequence analysis associated with serological data reveals the presence of two Potyvirus OYDV-G and LYSV, and GCLV, a Carlavirus, simultaneously infecting garlic plants. Deduced amino acid sequences of the Brazilian isolates were compared with related viruses reported in different geographical regions of the world. The analysis showed closed relations considering the Brazilian isolates of OYDV-G and GCLV, and large divergence considering LYSV isolate. The detection of these virus species was confirmed by specific reactions observed when coat protein genes of the Brazilian isolates were used as probes in dot-blot and Southern blot hybridization assays. In field natural viral re-infection of virus-free garlic was evaluated.

Sequence analysis of the capsid protein gene of an isolate of Apple stem grooving virus, and its survey in Southern Brazil

Apple stem grooving virus (ASGV) is one of the most important viruses infecting fruit trees. This study aimed at the molecular characterization of ASGV infecting apple (Malus domestica) plants in Santa Catarina (SC). RNA extracted from plants infected with isolate UV01 was used as a template for RT-PCR using specific primers. An amplified DNA fragment of 755 bp was sequenced. The coat protein gene of ASGV isolate UV01 contains 714 nucleotides, coding for a protein of 237 amino acids with a predicted Mr of approximately 27 kDa. The nucleotide and the deduced amino acid sequences of the coat protein gene showed identities of 90.9% and 97.9%, respectively, with a Japanese isolate of ASGV. Very high amino acid homologies (98.7%) were also found with Citrus tatter leaf capillovirus (CTLV), a very close relative of ASGV. These results indicate low coat protein gene variability among Capillovirus isolates from distinct regions. In a restricted survey, mother stocks in orchards and plants introduced into the country for large scale fruit production were indexed and shown to be infected by ASGV (20%), usually in a complex with other (latent) apple viruses (80%).

Cytopathological characterization of Mal de Río Cuarto virus in corn, wheat and barley

The Mal de Río Cuarto disease is caused by Mal de Río Cuarto virus (MRCV) transmitted by Delphacodes kuscheli. Comparative studies were carried out on the cytopathological alterations produced by MRCV in corn (Zea mays), wheat (Triticum aestivum) and barley (Hordeum vulgare), as seen with a transmission electron microscope. Corn plants were infected with viruliferous D. kuscheli collected from the endemic disease area (i.e. Río Cuarto County, Córdoba, Argentina). For the viral transmission to small grain cereal plants, laboratory rared insects were used. In this case, the inoculum source was wheat and barley plants infected with MRCV isolate grown in a greenhouse. Leaf samples with conspicuous symptoms were collected: enations and size reduction in corn; crenatures, swelling veins and dark green color in small grain cereals. Viral infection was corroborated by DAS-ELISA. Viroplasms containing complete and incomplete virus particles and fibrillar material were found in the cytoplasm of infected cells in all species. Mature virions were between 60 and 70 nm diameter. In wheat and barley, viroplasms and dispersed particles were observed only in phloem, while in corn virions were also found in cells of the bundle sheath. Crystalline arrays of particles were detected in corn enation constitutive cells. Tubular inclusions were found only in wheat samples. The three species showed abnormalities in the chloroplasts of affected cells. The results showed that MRCV cytopathology has similarities with other viruses from the genus Fijivirus, family family Reoviridae, but slight differences depending upon the host plant.

Cytopathology of callus cells infected with grapevine leafroll-associated virus 3

The cytopathology of grapevine (Vitis spp.) callus tissue infected with Grapevine leafroll-associated virus 3 (GLRaV-3), genus Vitivirus was studied in order to investigate the usefulness of callus cultures to study grapevine leafroll-associated viruses. Ultrathin sections were made from in vitro callus obtained from stems and shoots of GLRaV-3 infected grapevine plants. Callus was composed of two types of tissue. Translucent, soft callus was formed and composed of large loosely arranged cells, containing big vacuoles and a thin layer of cytoplasm. Other parts of the callus were brown-coloured and composed of small compactly arranged cells, which showed flexuous and rod-shaped closterovirus-like particles, with 10-12 nm in diameter, at higher magnifications. Groups of vesicles formed by a single membrane were also observed, with sizes ranging from 50-200 nm, containing fine fibrillar material, also typical of closterovirus infections. Virus concentration was monitored by Immunosorbent electron microscopy (ISEM) tests, which showed that in vitro culture of callus tissue from grapevine infected plants, could be used to study the GLRaV viruses through many successive generations, despite the decline in virus concentration after repeated transfers. No virus particles were observed in callus tissue obtained from healthy grapevines.

Traditional and transgenic strategies for controlling tomato-infecting begomoviruses

Viruses of to the family Geminiviridae are considered some of the most important pathogens in tropical and subtropical regions of the world. Members of one Geminiviridae genus, Begomovirus, have been causing severe losses, particularly in tomato (Lycopersicon esculentum) production in the Americas and the Caribbean. Several new begomoviruses have been reported in the region and, at least one, Tomato yellow leaf curl virus (TYLCV), has been brought in from the Old World via infected transplants. In addition, the recombination events that are playing an important role in Begomovirus diversity have increased the complexity of their control. This scenario has led to the search for control measures that go beyond traditional host genetic resistance, chemical controls and cultural practices. In this review, besides the recommended classical control measures, transgenic approaches will be discussed, as well as the mechanisms involved in their successful control of viruses.

Print-capture PCR for detection of tomato begomoviruses from plants and whiteflies

Print-capture (PC) Polymerase chain reaction (PCR) was evaluated as a novel detection method of plant viruses. Tomato (Lycopersicon esculentum) plants infected with begomovirus (fam. Geminiviridae, gen. Begomovirus) and viruliferous whiteflies were used to study the efficiency of the method. Print-capturing steps were carried out using non-charged nylon membrane or filter paper as the solid support for DNA printings. Amplified DNA fragments of expected size were consistently obtained by PCR from infected plants grown in a greenhouse, after direct application of printed materials to the PCR mix. However, virus detection from a single whitefly and from field-grown tomato samples required a high temperature treatment of printed material prior to PCR amplification. Comparison of nylon membrane and filter paper as the solid support revealed the higher efficiency of the nylon membrane. The application of print-capture PCR reduces the chances of false-positive amplification by reducing manipulation steps during preparation of the target DNA. This method maintains all the advantages of PCR diagnosis, such as the high sensitivity and no requirement of radioactive reagents.

Digitaalisia tartuntoja : liikettä ja elämää verkossa

Kirjallisuusarvostelu