Prior history of sexually transmitted diseases in women living with AIDS in Sao Paulo, Brazil

Objectives: To describe the epidemiological profile, risk behaviors, and the prior history of sexually transmitted diseases (STDs) in women living with acquired immunodeficiency syndrome (AIDS). Methods: Cross-sectional study, performed at the Centro de Referencia e Treinamento em DST/AIDS of Sao Paulo. The social, demographic, behavioral, and clinical data such as age, schooling, marital status, age at first sexual intercourse, number of sexual partners, parity, use of drugs, time of HIV diagnosis, CD4 count, and viral load determination were abstracted from the medical records of women living with AIDS who had gynecological consultation scheduled in the period from June 2008 to May 2009. Results: Out of 710 women who were scheduled to a gynecological consultation during the period of the study, 598 were included. Previous STD was documented for 364 (60.9%; 95% CI: 56.9%-64.8%) women. The associated factors with previous STDs and their respective risks were: human development index (HDI) <0.50 (ORaj = 5.5; 95% CI: 2.8-11.0); non-white race (ORaj = 5.2; 95% CI: 2.5-11.0); first sexual intercourse at or before 15 years of age (ORaj = 4.4; 95% CI: 2.3-8.3); HIV infection follow-up time of nine years or more (ORaj = 4.2; 95% CI: 2.3-7.8)]; number of sexual partners during the entire life between three and five partners (ORaj = 2.2; 95% CI: 1.1-4.6), and six or more sexual partners (ORaj = 3.9; 95% CI: 1.9-8.0%); being a sex worker (ORaj = 1.9; 95% CI: 1.1-3.1). Conclusions: A high prevalence of a prior history of STDs in the studied population was found. It is essential to find better ways to access HIV infection prevention, so that effective interventions can be more widely implemented. (C) 2012 Elsevier Editora Ltda. All rights reserved.

Prior history of sexually transmitted diseases in women living with AIDS in São Paulo, Brazil

OBJECTIVES: To describe the epidemiological profile, risk behaviors, and the prior history of sexually transmitted diseases (STDs) in women living with acquired immunodeficiency syndrome (AIDS). METHODS: Cross-sectional study, performed at the Centro de Referência e Treinamento em DST/AIDS of São Paulo. The social, demographic, behavioral, and clinical data such as age, schooling, marital status, age at first sexual intercourse, number of sexual partners, parity, use of drugs, time of HIV diagnosis, CD4 count, and viral load determination were abstracted from the medical records of women living with AIDS who had gynecological consultation scheduled in the period from June 2008 to May 2009. RESULTS: Out of 710 women who were scheduled to a gynecological consultation during the period of the study, 598 were included. Previous STD was documented for 364 (60.9%; 95% CI: 56.9%-64.8%) women. The associated factors with previous STDs and their respective risks were: human development index (HDI) < 0.50 (ORaj = 5.5; 95% CI: 2.8-11.0); non-white race (ORaj = 5.2; 95% CI: 2.5-11.0); first sexual intercourse at or before 15 years of age (ORaj = 4.4; 95% CI: 2.3-8.3); HIV infection follow-up time of nine years or more (ORaj = 4.2; 95% CI: 2.3-7.8)]; number of sexual partners during the entire life between three and five partners (ORaj = 2.2; 95% CI: 1.1-4.6), and six or more sexual partners (ORaj = 3.9; 95% CI: 1.9-8.0%); being a sex worker (ORaj = 1.9; 95% CI: 1.1-3.1). CONCLUSIONS: A high prevalence of a prior history of STDs in the studied population was found. It is essential to find better ways to access HIV infection prevention, so that effective interventions can be more widely implemented.

Investigation of the optical absorption of a magnetic colloid from the thermal to the electronic time-scale regime: measurement of the free-carrier absorption cross-section

The free-carrier absorption cross-section sigma of a magnetic colloid composed of magnetite nanoparticles dispersed in oil is obtained by using the Z-scan technique in different experimental conditions of the laser beam. We show that it is possible to obtain sigma with picosecond pulsed and millisecond chopped beams with pulse frequencies smaller than about 30 Hz. For higher pulse frequencies, the heating of the colloidal system triggers the appearance of the Soret effect. This effect artificially increases the value of sigma calculated from the experimental results. The limits of the different experimental setups are discussed. (C) 2012 Optical Society of America

Advances in primary immunodeficiency diseases in Latin America: epidemiology, research, and perspectives

Primary immunodeficiencies (PIDs) are genetic disorders of the immune system comprising many different phenotypes. Although previously considered rare, recent advances in their clinical, epidemiological, and molecular definitions are revealing how much we still need to learn about them. For example, geographical and ethnic variations as well as the impact of certain practices influence their frequency and presentation, making it necessary to consider their study in terms of regions. The Latin American Society for Immunodeficiencies was established as an organization dedicated to provide scientific support for basic and clinical research and to develop tools and educational resources to promote awareness in the medical community. Initiatives such as these are positively influencing the way PIDs are tackled in these countries, as shown by recent reports and publications. This paper provides a historical compilation and a current view of the many issues faced by scientists studying these diseases in these countries, highlighting the diverse scientific contributions and offering a promising perspective for the further developments in this field in Latin America.

Application of the Z-scan technique to determine the optical Kerr coefficient and two-photon absorption coefficient of magnetite nanoparticles colloidal suspension

We investigate the occurrence of the optical Kerr effect and two-photon absorption when an oil-based magnetic Fe3O4 nanoparticles colloidal suspension is illuminated with high intensity femtosecond laser pulses. The frequency of the pulses is controlled and the Z-scan technique is employed in our measurements of the nonlinear optical Kerr coefficient (n(2)) and two-photon absorption coefficient (beta). From these values it was possible to calculate the real and imaginary parts of the third-order susceptibility. We observed that increasing the pulse frequency, additional physical processes take place, increasing artificially the absolute values of n(2) and beta. The experimental conditions are discussed to assure the obtention of reliable values of these nonlinear optical parameters, which may be useful in all-optical switching and optical power limiting applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4723829]

Influence of nanoparticle size on the nonlinear optical properties of magnetite ferrofluids

The nonlinear index of refraction (n(2)) and the two-photon absorption coefficient (beta) of water-based ferrofluids made of magnetite nanocrystals of different sizes and with different coatings have been measured through the Z-scan technique, with ultrashort (femtoseconds) laser pulses. Their third-order susceptibility is calculated from the values of n(2) and beta. The influence of different particles' coatings and sizes on these nonlinear optical properties are investigated. The values of n(2) and beta depend more significantly on the nanoparticles' size than on the particular coating. We observe a decrease of beta as the nanoparticles' diameters decrease, although the optical gap is found to be the same for all samples. The results are interpreted considering modifications in the electronic orbital shape due to the particles' nanosize effect.