Atividade anti-HSV-1 in vitro de galactomanana quimicamente sulfatada de sementes de Leucaena leucocephala / In vitro anti-HSV-1 activity of a chemically sulfated galactomannan from Leucaena leucocephala seeds

Obteve-se uma galactomanana quimicamente sulfatada (LLS-2) a partir de polissacarídeo extraído de sementes de Leucaena leucocephala, a qual apresentou 15.2% de sulfato e grau de derivatização de 0,60, e, seu efeito antiviral sobre a replicação do vírus Herpes simplex tipo 1 (HSV-1) em células Vero foi avaliado pela metodologia de redução do número de unidades formadoras de placas. LLS-2 apresentou 93.7% de inibição da replicação viral à concentração de 2,5 ?g/ml, quando adicionado durante as etapas iniciais de replicação, com um índice de seletividade maior que 1.000, sugerindo que LLS-2 inibe a ligação de HSV-1 às células hospedeiras.

A galactomannan extracted from the seeds of Leucaena leucocephala was sulfated chemically, yielding a polymer (LLS-2) with 15.2% sulfate by weight (degree of sulfation 0.60), and its effect on the replication of Herpes simplex virus 1 (HSV-1) in Vero cells was investigated. When added during infection and early replication, LLS-2 showed 93.7% inhibition of HSV-1 replication at a concentration of 2.5 ?g/mL, according to the reduction in the number of viral plaques, and a selectivity index higher than 1,000, suggesting that it inhibits HSV-1 binding to the host cell.

Avaliação do potencial de uso do extrato bruto da fermentação por Streptomyces Viridosporus T7 A em medicinaveterinária / Evaluation of the potential applicability of Streptomyces Viridosporus T7 A crude fermentation extract in veterinary medicine / Evaluación del potencial de uso del extracto bruto de la fermentación por Streptomyces viridosporus T7A en medicina veterinaria

Desde a sua descoberta como produtoras de antibióticos, as bactérias do gênero Streptomyces têm sido muito estudadas, em função de seu grande interesse para a indústria. A maioria das cepas de Streptomyces sintetiza substâncias antibacterianas, antifúngicas, antitumorais, antiparasitárias, herbicidas e enzimas, que têm empregos em medicina e agricultura, bem como em vários processos biotecnológicos. Neste trabalho estudou-se a aplicação do extrato bruto enzimático obtido da fermentação por Streptomyces viridosporus T7A para uso veterinário. O extrato bruto enzimático foi submetido a testes de atividade antimicrobiana e de inocuidade, em cultivo celular e em camundongos. Observou-se efeito inibidor sobre cepas patogênicas Gram positivas (Staphylococcus aureus), porém não sobre bactérias Gram negativas (Salmonella sp., Pseudomonas sp. e Escherichia coli). Em cultivo celular, o extrato mostrou ausência de toxicidade e efeito citoprotetor, e em camundongos foi inócuo, e teve influência positiva no peso final nos grupos tratados.

Since discovered as antibiotics producers, Streptomyces genus bacteria had been studied to a great extent, because their great industrial interest. Most of the Streptomyces strains synthesize antibacterial, antifungal, antineoplastic, antiparasitic, and herbicide substances, as well as enzymes, which are used in medicine, agriculture and other biotechnological processes. We studied the potential applicability of Streptomyces viridosporus T7A crude fermentation extract in veterinary medicine. The antimicrobial properties of enzymatic crude extract were tested against pathogenic bacteria strains, and its innocuity was tested both in cellular cultives and mice. It was observed inhibitory effect against pathogenic Gram positive bacteria (Staphylococcus aureus), but not against pathogenic Gram negative bacteria (Salmonella sp., Pseudomonas sp., and Escherichia coli). In cellular cultives, the extract showed citoprotector effect and absence of toxicity. In mice, it was innocuous and had positive influence on the final weight in the treated groups.

Desde que fueran descubiertas como productoras de antibióticos, las bacterias del género Streptomyces vienen siendo muy estudiadas, por tener gran interés para la industria. La mayoría de las variedades de Streptomyces sintetiza substancias antibacterianas, antifúngicas, antitumorales, antiparasitarias y herbicidas, así como enzimas que se usan en medicina, agricultura y otros procesos biotecnológicos. En este trabajo, se estudió el potencial de uso del extracto bruto de la fermentación por Streptomyces viridosporus T7A en medicina veterinaria. Las propiedades antimicrobianas del extracto bruto enzimático fueran testadas contra bacterias patogénicas, así como se testó su inocuidad tanto en cultivos celulares cuanto en ratones. Se observó efecto inhibitorio sobre bacterias patogénicas Gram positivas (Staphylococcus aureus), pero no sobre bacterias Gram negativas (Salmonella sp., Pseudomonas sp. y Escherichia coli). En cultivo celular, el extracto mostró ausencia de toxicidad y efecto citoprotector, y en ratones fue inocuo, y ha influenciado positivamente el peso final de los grupos tratados.

Investigation of Neospora sp. and Toxoplasma gondii antibodies in mares and in precolostral foals from Parana State, Southern Brazil.

Antibodies to Neospora sp. and Toxoplasma gondii were measured in mares and precolostral foals from a farm in Parana State, Brazil. An indirect fluorescent antibody test (IFAT) was used to determine specific antibodies. Three sampling points, 2003, 2004 and at parturition were included in the study, but not all horses are represented at a parturition time point. In 2003, antibodies to Neospora were detected in 17 mares (47%) at 1:50 dilution and in 5 mares (13.8%) at 1:100 dilution. In 2004, antibodies to Neospora were found in 11/36 (30%) horses with titers of 1:50 and in 6 mares (16.6%) at 1:100 dilution. The prevalence of antibodies against T. gondii was 2.7% in mares, either in 2003 and 2004. Evidence for the role of Neospora sp. in equine reproduction failure was not observed in the farm. Immunoglobulin G antibodies to Neospora were found in two of the nine precolostrum foals. Four seronegative foals were born from seronegative mothers, and three seronegative foals were born from seropositive mothers (1:50). Two seropositive precolostrum foals were born from seropositive mothers (1:50). The foals were born clinically normal, and T. gondii antibodies were not detected in their serum samples. The total immunoglobulins values detected on seronegative precolostrum foals were lower than the levels observed in the seropositive foals. This data warrants additional studies to differentiate N. hughesi and N. caninum serologically and determination if these parasites were associated with equine neurological disease and reproductive failure.

Serological diagnosis of neosporosis in a herd of dairy cattle in southern Brazil.

Neospora caninum-specific antibodies were detected in 60 of 172 (34.8%) dairy cattle by enzyme-linked immunosorbent assay (ELISA) in a herd from Parana State, Brazil. The seropositive animals included 47 of 126 (37.3%) adult cows, 7 of 29 (24%) heifers (1-2 yr), 4 of 15 (27%) heifers (5 mo-1 yr), and 2 precolostral samples. Data collected over a 9-yr follow-up period revealed that the proportion of pregnancies ending in abortion was 20% (31/154) among ELISA seropositive cows and 8% (15/193) among seronegative cows. The farm recorded 46 abortions, of which 31 (67.3%) were from seropositive cows. All sera positive by ELISA (n = 60) and sera from cows (n = 11) that were ELISA-negative but that had aborted were tested by the indirect fluorescent antibody test (IFAT) at dilutions from 1:25 to 1:200. All sera from ELISA-positive cows (n = 47) had an IFAT titer of 1:25:35 (74%) of these sera were also seropositive at a dilution of 1:200 (IFAT). Cows seropositive by ELISA had a 4-fold increased risk of having aborted at least once, compared to ELISA-seronegative cows. This association was statistically significant (P = 0.0016). The attributable fraction for this association indicated that approximately 76% of the risk for a cow having a history of abortion was attributable to seroconversion to N. caninum.