Genetic variability in G2 and F2 region between biological clones of human respiratory syncytial virus with or without host immune selection pressure

Human respiratory syncytial virus (HRSV) is an important respiratory pathogens among children between zero-five years old. Host immunity and viral genetic variability are important factors that can make vaccine production difficult. In this work, differences between biological clones of HRSV were detected in clinical samples in the absence and presence of serum collected from children in the convalescent phase of the illness and from their biological mothers. Viral clones were selected by plaque assay in the absence and presence of serum and nucleotide sequences of the G2 and F2 genes of HRSV biological clones were compared. One non-synonymous mutation was found in the F gene (Ile5Asn) in one clone of an HRSV-B sample and one non-synonymous mutation was found in the G gene (Ser291Pro) in four clones of the same HRSV-B sample. Only one of these clones was obtained after treatment with the child's serum. In addition, some synonymous mutations were determined in two clones of the HRSV-A samples. In conclusion, it is possible that minor sequences could be selected by host antibodies contributing to the HRSV evolutionary process, hampering the development of an effective vaccine, since we verify the same codon alteration in absence and presence of human sera in individual clones of BR-85 sample.

Neutralising antibodies for Mayaro virus in Pantanal, Brazil

The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in South America. A serosurvey for Mayaro virus (MAYV), eastern (EEEV), western (WEEV) and Venezuelan (VEEV) equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. Sera were tested for specific viral antibodies using plaque-reduction neutralisation test. From a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and WEEV and 484 had no history of immunisation, 10 (1.3%) were seropositive for MAYV and two (0.3%) for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the 484 equids without history of immunisation, 48 (9.9%) were seropositive for EEEV and four (0.8%) for WEEV using the same criteria. Among the sheep, five were sero- positive for equine encephalitis alphaviruses, with one (0.4%) for EEEV, one (0.4%) for WEEV and three (1.3%) for VEEV. Regarding free-ranging caimans, one (1.1%) and three (3.4%), respectively, had low titres for neutralising antibodies to VEEV and undetermined alphaviruses. The neurological disorder outbreak could not be linked to the alphaviruses tested. Our findings represent strong evidence that MAYV and all equine encephalitis alphaviruses circulated in the Pantanal.

Experimental benznidazole treatment of Trypanosoma cruzi II strains isolated from children of the Jequitinhonha Valley, Minas Gerais, Brazil, with Chagas disease

Trypanosoma cruzi strains from distinct geographic areas show differences in drug resistance and association between parasites genetic and treatment response has been observed. Considering that benznidazole (BZ) can reduce the parasite burden and tissues damage, even in not cured animals and individuals, the goal is to assess the drug response to BZ of T. cruzi II strains isolated from children of the Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected and treated with BZ in both phases of infection were compared with the untreated and evaluated by fresh blood examination, haemoculture, polymerase chain reaction, conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in the acute phase, a significant decrease in parasitaemia was observed for all strains. Positive parasitological and/or serological tests in animals treated during the acute and chronic (95.1-100%) phases showed that most of the strains were BZ resistant. However, beneficial effect was demonstrated because significant reduction (p < 0.05%) and/or suppression of parasitaemia was observed in mice infected with all strains (acute phase), associated to reduction/elimination of inflammation and fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals, what suggest that BZ use may be recommended at least for recent chronic infection of the studied region.

BAY 41-2272 activates host defence against local and disseminated Candida albicans infections

In our previous study, we have found that 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]-pyrimidin-4-ylamine (BAY 41-2272), a guanylate cyclase agonist, activates human monocytes and the THP-1 cell line to produce the superoxide anion, increasing in vitro microbicidal activity, suggesting that this drug can be used to modulate immune functioning in primary immunodeficiency patients. In the present work, we investigated the potential of the in vivo administration of BAY 41-2272 for the treatment of Candida albicans and Staphylococcus aureus infections introduced via intraperitoneal and subcutaneous inoculation. We found that intraperitoneal treatment with BAY 41-2272 markedly increased macrophage-dependent cell influx to the peritoneum in addition to macrophage functions, such as spreading, zymosan particle phagocytosis and nitric oxide and phorbol myristate acetate-stimulated hydrogen peroxide production. Treatment with BAY 41-2272 was highly effective in reducing the death rate due to intraperitoneal inoculation of C. albicans, but not S. aureus. However, we found that in vitro stimulation of peritoneal macrophages with BAY 41-2272 markedly increased microbicidal activities against both pathogens. Our results show that the prevention of death by the treatment of C. albicans-infected mice with BAY 41-2272 might occur primarily by the modulation of the host immune response through macrophage activation. .

Bats and zoonotic viruses: can we confidently link bats with emerging deadly viruses?

An increasingly asked question is 'can we confidently link bats with emerging viruses?'. No, or not yet, is the qualified answer based on the evidence available. Although more than 200 viruses - some of them deadly zoonotic viruses - have been isolated from or otherwise detected in bats, the supposed connections between bats, bat viruses and human diseases have been raised more on speculation than on evidence supporting their direct or indirect roles in the epidemiology of diseases (except for rabies). However, we are convinced that the evidence points in that direction and that at some point it will be proved that bats are competent hosts for at least a few zoonotic viruses. In this review, we cover aspects of bat biology, ecology and evolution that might be relevant in medical investigations and we provide a historical synthesis of some disease outbreaks causally linked to bats. We provide evolutionary-based hypotheses to tentatively explain the viral transmission route through mammalian intermediate hosts and to explain the geographic concentration of most outbreaks, but both are no more than speculations that still require formal assessment.

Technical and economical selection of optimum transfer-transport method in solid waste management in metropolitan Cities

Transfer-transport of the waste is one of key functional elements in solid waste management from technical and financial viewpoint. Unfortunately very few reach activities has been conducted in this field regarding local characteristic of phenomenon which urges undertaking local surveys and research projects. Tehran Organization of Waste Recycling and Composting has decided to investigate different transfer-transport options for new Tehran landfill in Houshang Site which is located in far distance from Current landfill in Kahrizak. The study surveyed 3 main options comprising of 8 alternatives. This alternatives covered so many aspects of transfer-transport like road or rail transport, compaction of waste, size of containers and system of loading/unloading, The surveyed showed that the two alternative of heavy compaction in 65m3 semi-trailers will be the most economical system that enjoys so many environmental-ecological advantages over current practice

Investigation of energy recovery from poultry litter and municipal solid waste by thermochemical conversion method in India.

The waste disposal is becoming a major threat to environmental issues and to sustainable development of mankind. The rapid growth in population and enormous developmental activities are the main causes for the generation of waste in many forms. Hence there is need to redress the concern on environment and efforts to be made for effective collection and disposal of wastes. Most of the solid waste is a mix of household wastes, street wastes, commercial and institutional wastes containing organic as well as inorganic matter. This offers better opportunity to recover energy from organic fraction of wastes by adapting suitable processing and treatment technologies. This paper describes the various technologies need to be adopted for the disposal of poultry waste and municipal solid waste. More emphasis has been given on waste disposal technologies for better environment and economics. The advantages and disadvantages of each disposal technology have been briefed.

Economic utilization of agro-industrial wastes through solid state fermentation by aspergillus niger f-21 for alpha-amylase production

Solid state fermentation technique was carried out in utilization of various agro-industrial wastes from different industries for the production of fungal alpha-amylase [E.C. 3.2.1.1] by locally isolated strain of Aspergillus niger. Culture conditions affect enzyme formation such as incubation time, initial pH, moisture level, moistening agent and nitrogen source were investigated. High level of enzyme activity could be obtained after 48 hr using potato peels as a substrate with initial pH 6.0 using whey permeate level of 50% as a moistening agent and urea as a cheap nitrogen source at level 400 mg N/1 moistening agent. The obtained enzyme has an activity of 620 U/g fermented substrate. The obtained enzyme was stable in a wide range of pH between 3-9 as well as the enzyme proceeds through wide range of temperature ranged between 50-85C. The enzyme looses only about 10% from its optimal activity between 90-100C and at 105C the relative activity was about 27%. The crude enzyme was heat stable when incubated at 70C for 39 hr retaining its maximum activity. Crude enzyme was applied for potato starch digestion using different slurries concentrations up to 30% giving about 96% digestion

Análisis de costo de sistemas de tratamiento para aguas residuales industriales / Cost analysis of treatment systems of industrial residual waters

En este trabajo se presentan los resultados obtenidos para los costos involucrados en la instalación y operación de cuatro alternativas de sistema de tratamiento de aguas residuales industriales. Los sistemas estudiados fueron los siguientes: Sistema N§1, el más completo, incluye tratamiento primario (tamizado primario, igualación, neutralización y sedimentación primaria); tratamiento secundario (físico-químico y oxidación biológica) y tratamiento de los lodos residuales. Sistema N§2, el cual consta de tratamiento primario, tratamiento secundario físico-químico y tratamiento de los lodos residuales. Sistema N§3, que consiste en tratamiento primario, tratamiento secundario de oxidación biológica y tratamiento de lodos residuales y el sistema N§ 4, el más simple, consta solamente de tratamiento primario. Los resultados obtenidos para la inversión total, los costos operacionales anuales y los costos anuales necesarios para instalar y operar las plantas de tratamiento se presentan en función del caudal a ser tratado