ABSTRACT
Abstract The Equine Strangles, caused by Streptococcus equi subs. equi, is a contagious disease, causing high rates of morbidity been responsible for important economic losses. The M protein synthesized by S. equi plays an important role in the pathogenesis and is a promising candidate for a vaccine antigen. The innate immune system is responsible for the first immune response against microorganisms, this response is mediated by receptors that detect PAMPs and their activation trigger crucial modulation of the adaptative immune response. This work describes the immune response of S. equi subs. equi. recombinant SeM protein, using Escherichia coli BL21 (DE3) as an expression and delivery vaccine system. To characterize and to determine the vaccine efficacy, mice were vaccinated as followed: 1. Recombinant E. coli expressing rSeM protein; 2. The same recombinant E. coli, inactivated adsorbed in Alumen; 3. Purified rSeM protein adsorbed in Alumen; 4. Inactivated S. equi whole cells adsorbed in Alumen; 5. Control group. All vaccinated mice developed protective response against S. equi infection, however the groups that received the E. coli expressing rSeM presented significant higher IgG level than other vaccinated groups. The recombinant E. coli delivery vaccine system also induced a highest IgG response than inactivated S. equi or purified rSeM vaccines in horses. This study evidence that the recombinant E. coli, live or inactivated, enhanced the humoral response, reaching significant higher antibodies levels than those obtained in the vaccination with the bacterin or purified antigen, showing the feasibility of producing low-cost vaccines against strangles.
ABSTRACT
Resumo Objetivo Comparar a prevalência e os fatores associados à transmissão vertical de HIV-1 entre grávidas tratadas de 1998-2004 e de 2005-2011 em um serviço de referência de cuidado de pacientes com HIV no sul do Brasil. Métodos Estudo descritivo e analítico que usou as bases de dados de laboratórios da Rede Nacional de Laboratórios de CD4 e Carga Viral de DST/Aids do Ministério da Saúde. As grávidas com HIV-1 foram selecionadas em uma pesquisa ativa de informações clínicas e dados obstétricos e neonatais em seus prontuários médicos entre 1998-2011. Resultados Foram analisadas 102 grávidas entre 1998 e 2004 e 251 entre 2005-2011, no total 353 crianças nascidas de grávidas com HIV-1. Observou-se que a transmissão vertical foi de 11,8% entre 1998 e 2004 e de 3,2% entre 2005-2011 (p < 0,001). O maior uso de medicamentos antirretrovirais (p = 0,02), a redução na carga viral (p < 0,001) e o tempo de ruptura de membranas menor do que quatro horas (p < 0,001) foram associados à redução nos fatores de transmissão vertical quando os dois períodos são comparados. Conclusão Observou-se uma redução na taxa de transmissão vertical nos últimos anos. De acordo com as variáveis estudadas, sugere-se que os fatores de risco de transmissão vertical de HIV-1 foram ausência de terapia antirretroviral, alta carga viral das grávidas e tempo de ruptura maior do que quatro horas.
Abstract Objective To compare the prevalence and factors associated with vertical transmission of human immunodeficiency virus 1 (HIV-1) among pregnant women treated in the periods of 1998-2004 and 2005-2011 in a reference service for the care of HIV-infected patients in southern Brazil. Methods This was a descriptive and analytical study that used the databases of laboratories from the CD4 and STDs/AIDS Viral Load National Laboratory Network of the Brazilian Ministry of Health. HIV-1-infected pregnant women were selected after an active search for clinical information and obstetric and neonatal data from their medical records between the years of 1998 and 2011. Results 102 pregnant women were analyzed between 1998 and 2004 and 251 in the period between 2005 and 2011, totaling 353 children born to pregnant women with HIV-1. It was observed that the vertical transmission rate was 11.8% between 1998 and 2004 and 3.2% between 2005 and 2011 (p < 0.001). The increased use of antiretroviral drugs (p = 0.02), the decrease in viral load (p < 0.001), and time of membrane rupture lower than 4 h (p < 0.001) were associated with the decrease of vertical transmission factors when comparing the two periods. Conclusion It was observed a decrease in the rate of vertical transmission in recent years. According to the studied variables, is suggested that the risk factors for vertical transmission of HIV-1 were absence of antiretroviral therapy, high viral load in the pregnant women, and membrane rupture time >4 h.