Effects of exposure to cigarette smoke prior to pregnancy in diabetic rats

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to evaluate the effects of cigarette smoke exposure before pregnancy on diabetic rats and their offspring development.</p> <p>Methods</p> <p>Diabetes was induced by streptozotocin and cigarette smoke exposure was conducted by mainstream smoke generated by a mechanical smoking device and delivered into a chamber. Diabetic female Wistar rats were randomly distributed in four experimental groups (n minimum = 13/group): nondiabetic (ND) and diabetic rats exposed to filtered air (D), diabetic rats exposed to cigarette smoke prior to and into the pregnancy period (DS) and diabetic rats exposed to cigarette smoke prior to pregnancy period (DSPP). At day 21 of pregnancy, rats were killed for maternal biochemical determination and reproductive outcomes.</p> <p>Results</p> <p>The association of diabetes and cigarette smoke in DSPP group caused altered glycemia at term, reduced number of implantation and live fetuses, decreased litter and maternal weight, increased pre and postimplantation loss rates, reduced triglyceride and VLDL-c concentrations, increased levels of thiol groups and MDA. Besides, these dams presented increased SOD and GSH-Px activities. However, the increased antioxidant status was not sufficient to prevent the lipid peroxidation observed in these animals.</p> <p>Conclusion</p> <p>Despite the benefits stemming from smoking interruption during the pregnancy of diabetic rats, such improvement was insufficient to avoid metabolic alterations and provide an adequate intrauterine environment for embryofetal development. Therefore, these results suggest that it is necessary to cease smoking extensive time before planning pregnancy, since stopping smoking only when pregnancy is detected may not contribute effectively to fully adequate embryofetal development.</p

Influence of maternal periuterine and periovarian fat on reproductive performance and fetal growth in rats

Abstract We aimed to evaluate how high-fat diet consumption can interfere with rat reproductive performance and fetal development. High-fat diet (HFD) was initiated in 30-day-old rats, distributed into two groups (n=7 animals/group): Rats receiving a standard diet and rats receiving HFD. At adulthood, the rats were mated, and on day 21 of pregnancy, the females were anesthetized, decapitated, and submitted to laparotomy to obtain visceral and periovarian adipose tissue. The uterine horns were exposed for analysis of maternal reproductive performance. The fetuses and placentas were weighed and analyzed. Pearson’s correlation test was used, and p<0.05 was considered significant. There was a significant positive correlation (HFD consumption x increased periovarian fat) and a negative correlation with the implantation, live fetus numbers and lower litter weight. Furthermore, the increased relative weight of periuterine fat was related to the lower number of live fetuses and litter weight. Regarding the fetal weight classification, there was a negative correlation between the relative weight of periovarian fat and the percentage of fetuses appropriate for gestational age and large for gestational age. Therefore, our findings show that HFD maternal intake negatively influenced on reproductive performance and fetal growth

Foundation Pattern, Productivity and Colony Success of the Paper Wasp, Polistes versicolor

Polistes versicolor (Olivier) (Hymenoptera: Vespidae) colonies are easily found in anthropic environments; however there is little information available on biological, ecological and behavioral interactions of this species under these environmental conditions. The objective of this work was to characterize the foundation pattern, the productivity, and the success of colonies of P. versicolor in anthropic environments. From August 2003 to December 2004, several colonies were studied in the municipal district of Juiz de Fora, Southeastern Brazil. It was possible to determine that before the beginning of nest construction the foundress accomplishes recognition flights in the selected area, and later begins the construction of the peduncle and the first cell. As soon as new cells are built, the hexagonal outlines appear and the peduncle is reinforced. Foundation of nests on gypsum plaster was significantly larger (p < 0.0001; χ2 test) in relation to the other types of substrate, revealing the synantropism of the species. On average, the P. versicolor nest presents 244.2 ± 89.5 (100–493) cells and a medium production of 171.67 ± 109.94 (37–660) adults. Cells that produced six individuals were verified. Usually, new colonies were founded by an association of females, responsible for the success of 51.5%. Although these results enlarge knowledge on the foundation pattern of P. versicolor in anthropic environments, other aspects of the foundation process require further investigation

The role of males in a neotropical paper wasp, Polistes ferreri Saussure, 1853 (Hymenoptera, Vespidae, Polistinae)

There are a few studies about the behavior of males of paper wasps in the colonies; however, some activities performed by males , such as nest maintenance and brood care, have been described in the literature. Between February and June 2001, behavioral observations were carried out on three colonies of Polistes ferreri Saussure, 1853, from postemergence to decline phases. Productivity,emergence time, permanence on the combs and behavioral repertory were verified during the observations. The emergence of males took place between February and June, and the productivity was 17,66±12,05 males per colony. Such values were smaller than those found for other species of Polistes. Seventeen behavioral acts were registered for males of P. ferreri. Males remained in the colony for a short period (average of 8,06 days). Some performed acts by males seem to be related to the tasks in the nests and to the mating behavior

Comparison of Methods for the Identification of Coagulase-negative Staphylococci

Coagulase-negative staphylococci (CNS) species identification is still difficult for most clinical laboratories. The scheme proposed by Kloos and Schleifer and modified by Bannerman is the reference method used for the identification of staphylococcal species and subspecies; however, this method is relatively laborious for routine use since it requires the utilization of a large number of biochemical tests. The objective of the present study was to compare four methods, i.e., the reference method, the API Staph system (bioMérieux) and two methods modified from the reference method in our laboratory (simplified method and disk method), in the identification of 100 CNS strains. Compared to the reference method, the simplified method and disk method correctly identified 100 and 99% of the CNS species, respectively, while this rate was 84% for the API Staph system. Inaccurate identification by the API Staph method was observed for Staphylococcus epidermidis (2.2%), S. hominis (25%), S. haemolyticus (37.5%), and S. warneri (47.1%). The simplified method using the simple identification scheme proposed in the present study was found to be efficient for all strains tested, with 100% sensitivity and specificity and proved to be available alternative for the identification of staphylococci, offering, higher reliability and lower cost than the currently available commercial systems. This method would be very useful in clinical microbiology laboratory, especially in places with limited resources

Colony cycle, foundation strategy and nesting biology of a Neotropical paper wasp Ciclo colonial, estrategia de la fundación y biología de anidación de una avispa de papel neotropical

Polistes ferreri Saussure, 1853 is a Neotropical paper wasp often found in anthropic environments. However, there is little information available on biological, ecological and behavioral interactions of this species under these environmental conditions. This study investigated the colony cycle, foundation strategy and nesting biology of this species. From March of 2000 to February of 2004, several colonies were studied in the municipal district of Juiz de Fora, in southeastern Brazil. The colony cycle events of P. ferreri are concentrated in specific periods of the year. The colonies are established principally by association of females, the latter is the foundation strategy that confers the greatest success. Nidification on manmade substrates seems common for the species. The peduncle of the nest is increased in width to support the weight of colony members. Likewise, cells are increased in height, in accordance with the size of the layers of meconium, allowing accommodation of the immature. It is suggested that, at least for post-emergent colonies of P. ferreri, the cost of nest construction is not a factor limiting the development of the colonies. Finally, the results also support the idea that the reuse of cells is an advantageous strategy because it saves costs related to the construction of new cells.Polistes ferreri Saussure, 1853 es una avispa de papel neotropical encontrada a menudo en ambientes antrópicos. Sin embargo, hay poca información disponible sobre las interacciones biológicas, ecológicas y de comportamiento de esta especie en estas condiciones ambientales. Este estudio investigó el ciclo de la colonia, la estrategia de fundación y la biología de anidación de esta especie. Desde marzo de 2000 a febrero de 2004, varias colonias fueron estudiadas en el municipio de Juiz de Fora, en el sureste de Brasil. Los eventos del ciclo de la colonia de P. ferreri se concentran en determinados períodos del año. Las colonias se establecen, principalmente, por asociación de hembras, siendo esta la estrategia que se traduce en un mayor éxito. La nidificación en sustratos artificiales parece común para la especie. El pedúnculo del nido va aumentando en ancho para soportar el peso de los miembros de la colonia. Del mismo modo, las celdas aumentan en altura, de acuerdo con el tamaño de las capas de meconio, lo que permite el alojamiento de los inmaduros. Se sugiere que, al menos para las colonias de postemergentes de P. ferreri, el costo de la construcción del nido no es un factor que limita el desarrollo de las colonias. Por último, los resultados también apoyan la idea de que la reutilización de las celdas es una estrategia ventajosa porque reduce los costos relacionados con la construcción de nuevas celdas