10 research outputs found
INSECTICIDE-TREATED BED NETS IN RONDÔNIA, BRAZIL: EVALUATION OF THEIR IMPACT ON MALARIA CONTROL
Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region
A case–control analysis of oral contraceptive use and breast cancer subtypes in the African American Breast Cancer Epidemiology and Risk Consortium
Abstract Introduction Recent oral contraceptive (OC) use has been consistently associated with increased risk of breast cancer, but evidence on specific breast cancer subtypes is sparse. Methods We investigated recency and duration of OC use in relation to molecular subtypes of breast cancer in a pooled analysis of data from the African American Breast Cancer Epidemiology and Risk Consortium. The study included 1,848 women with estrogen receptor-positive (ER+) breast cancer, 1,043 with ER-negative (ER-) breast cancer (including 494 triple negative (TN) tumors, which do not have receptors for estrogen, progesterone, and human epidermal growth factor 2), and 10,044 controls. Multivariable polytomous logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for exposure categories relative to never use, controlling for potential confounding variables. Results OC use within the previous 5 years was associated with increased risk of ER+ (OR 1.46, 95% CI 1.18 to 1.81), ER- (OR 1.57, 95% CI 1.22 to 1.43), and TN (OR 1.78, 95% CI 1.25 to 2.53) breast cancer. The risk declined after cessation of use but was apparent for ER+ cancer for 15 to 19 years after cessation and for ER- breast cancer for an even longer interval after cessation. Long duration of use was also associated with increased risk of each subtype, particularly ER-. Conclusions Our results suggest that OC use, particularly recent use of long duration, is associated with an increased risk of ER+, ER-, and TN breast cancer in African American women. Research into mechanisms that explain these findings, especially the association with ER- breast cancer, is needed
Influence of aerobic fitness on age-related lymphocyte DNA damage in humans: relationship with mitochondria respiratory chain and hydrogen peroxide production
The aim of this study was to analyze the influence of aerobic fitness (AF) on age-related lymphocyte DNA damage in humans, giving special attention to the role of the mitochondrial respiratory chain and hydrogen peroxide production. Considering age and AF (as assessed by VO2max), 66 males (19–59 years old) were classified as high fitness (HF) or low fitness (LF) and distributed into one of the following groups: young adults (19–29 years old), adults (30–39 years old), and middle-aged adults (over 40 years old). Peripheral lymphocytes obtained at rest were used to assess DNA damage (strand breaks and formamidopyrimidine DNA glycosylase (FPG) sites through the comet assay), activity of mitochondrial complexes I and II (polarographically measured), and the hydrogen peroxide production rate (assayed by fluorescence). Results revealed a significant interaction between age groups and AF for DNA strand breaks (F = 8.415, p = .000), FPG sites (F = 11.766, p = .000), mitochondrial complex I activity (F = 7.555, p = .000), and H2O2 production (F = 7.500, p = .000). Except for mitochondrial complex II activity, the age variation of the remaining parameters was significantly attenuated by HF. Considering each AF level, an increase in DNA strand breaks and FPG sites with age (r = 0.655, p = 0.000, and r = 0.738, p = 0.000, respectively) was only observed in LF. Moreover, decreased mitochondrial complex I activity with age (r = −.470, p = .009) was reported in LF. These results allow the conclusion that high AF seems to play a key role in attenuating the biological aging process
A review on macrobenthic trophic relationships along subtropical sandy shores in southernmost Brazil
Main trophic relationships that occur along the exposed sandy shores in southernmost Brazil
(,336 S) are established taking into account several biological compartments operating at
morphodynamically distinct environments. Beaches are predominantly of the intermediate type but
some stretches of coastline are truly dissipative (Cassino Beach) or tending-to-reflective (Concheiros
Beach), presenting thus diverse biological compartments and inhabitant macrobenthic assemblages.
Dense concentrations of the surf-zone diatom Asterionellopsis glacialis are responsible - at least for the
intermediate shorelines - for the most year-round primary production, sustaining several consumers up to
tertiary level. Among them, bivalves Amarilladesma mactroides, Donax hanleyanus and the hippid crab
Emerita brasiliensis can account for more than 95% of all the surf-zone secondary production, in addition
to the elevated biomass of the suspension-feeder polychaete Spio gaucha and the scavenger isopod
Excirolana armata. Crabs, whelks, carnivorous polychaetes, seabirds and surf-zone fishes may also be
present and occupy superior trophic levels depending on the beach morphodynamics. Based on the high
species richness, abundance and the role of macrobenthic fauna in transferring matter and energy to
seabirds and the surf-zone fish assemblages, we address this important issue on the Southwestern Atlantic
ecology. Conservation efforts should be implemented for the southernmost Brazilian sandy shores, at
least for those non urbanized areas.As principais relac¸o˜ es tro´ ficas observadas ao longo da costa arenosa exposta do extremo sul do
Brasil (,336 S) sa˜o estabelecidas levando-se em considerac¸a˜o os va´ rios compartimentos biolo´ gicos que
operam em ambientes morfodinamicamente distintos. Estas praias sa˜o predominantemente do tipo
intermedia´ rio, embora alguns trechos sejam dissipativos (Praia do Cassino) ou apresentem tendeˆncias
reflectivas (Praia dos Concheiros), possuindo compartimentos biolo´ gicos diversificados e associac¸o˜es
macrobentoˆnicas residentes. Densas concentrac¸o˜ es da diatoma´cea Asterionellopsis glacialis sa˜o
responsa´ veis - pelo menos para as praias intermedia´ rias - por grande parte da produtividade prima´ ria
anual, sustentando va´ rios consumidores ate´ o nı´vel tercia´ rio. Entre estes, os bivalves Amarilladesma
mactroides, Donax hanleyanus e o crusta´ceo Emerita brasiliensis sa˜o responsa´ veis por mais de 95% de toda
a produc¸a˜o secunda´ ria da zona de surfe, em adic¸a˜o a` elevada biomassa do poliqueta suspensı´voro Spio
gaucha e do iso´pode necro´fago Excirolana armata. Caranguejos, gastro´ podes, poliquetas carnı´voros, aves
marinhas e peixes da zona de surfe tambe´m podem estar presentes, ocupando nı´veis tro´ ficos superiores
dependendo da morfodinaˆmica praial. Baseado na alta riqueza de espe´cies, na abundaˆncia e no papel da
macrofauna bentoˆ nica em transferir mate´ria e energia para as aves marinhas e as assemble´ias de peixes da
zona de surfe, esta importante questa˜o ecolo´ gica do Atlaˆntico Sudoeste foi investigada. Esforc¸os de
conservac¸a˜o devem ser implementados nas praias arenosas do extremo sul do Brasil, pelo menos naquelas
a´ reas na˜o urbanizadas