Prenatal lipopolysaccharide reduces motor activity after an immune challenge in adult male offspring

Prenatal lipopolysaccharide (LPS) exposure causes reproductive, behavioral and neurochemical injuries in both the mother and pups. Previous investigations by our group showed that prenatal LPS administration (100 mu g/kg, i.p.) on gestational day 9.5 impaired the male offspring`s social behavior in infancy and adulthood. In the present study, we investigated whether these social behavioral changes were associated with motor activity impairment. Male rat pups treated prenatally with LPS or not were tested for reflexological development and open field general activity during infancy. In adulthood, animals were tested for open field general activity, haloperidol-induced catalepsy and apomorphine-induced stereotypy; striatal dopamine levels and turnover were also measured. Moreover, LPS-treated or untreated control pups were challenged with LPS in adulthood and observed for general activity in the open field. In relation to the control group, the motor behavior of prenatally treated male pups was unaffected at basal levels, both in infancy and in adulthood, but decreased general activity was observed in adulthood after an immune challenge. Also, striatal dopamine and metabolite levels were decreased in adulthood. In conclusion, prenatal LPS exposure disrupted the dopaminergic system involved with motor function, but this neurochemical effect was not accompanied by behavioral impairment, probably due to adaptive plasticity processes. Notwithstanding, behavioral impairment was revealed when animals were challenged with LPS, resulting in enhanced sickness behavior. (C) 2010 Elsevier B.V. All rights reserved.

Prenatal Lipopolysaccharide Reduces Social Behavior in Male Offspring

Objective: This study investigated the relationship between maternal sickness behavior during pregnancy and offspring development and behavior. Methods: Pregnant Wistar rats were administered with lipopolysaccharide (LPS, 100 mu g/kg, i.p.) on gestation day (GD) 9.5. Dams` sickness behavior was analyzed, and at birth, offspring number and weight were evaluated. Male offspring was evaluated through physical development, play behavior, adult social interaction, plus maze studies and morphological analysis of the brain. Results: Results, with respect to the control group, showed that: (1) LPS decreased general activity, food intake, and weight gain in dams, but no pyrexia was observed following treatment; (2) LPS reduced litter size, but no alterations in physical development were observed; (3) LPS reduced play behavior parameters in baby rats; (4) LPS decreased adult social interaction; (5) no alterations were observed between groups on plus maze studies; (6) no differences were observed between groups on morphological analyses of the brain. Conclusion: These data reveal that LPS administered on GD 9.5 impaired male offspring`s social behavior in infancy and adulthood. These results may be related to an alteration in motivational states or/and increased anxiety. Copyright (C) 2010 S. Karger AG, Basel

Prenatal Lipopolysaccharide Exposure Affects Maternal Behavior and Male Offspring Sexual Behavior in Adulthood

Objective: This study investigates the effects of prenatal lipopolysaccharide (LPS) exposure on the maternal behavior of pregnant rats and the physical development and sexual behavior of their male offspring in adulthood. Methods: For two experiments, pregnant rats were injected with LPS (250 mu g/kg, i.p.) on gestation day (GD) 21. In the first experiment, the maternal behavior (postnatal day, PND, 6) and the dam`s open-field general activity (PND7) were evaluated. In the second experiment, the maternal pre- and postnatal parameters, the pup`s development, the offspring`s sexual behavior in adulthood, and the pup`s organ weights were assessed. Results: Compared to the control group, the LPS-treated dams presented reduced maternal behavior, decreased general activity, a smaller body weight difference between GD21 and PND1, a greater number of perinatal deaths, and smaller litters. For the male pups, LPS treatment resulted in a decreased body weight on PND2, whereas the anogenital distance and the day of testis descent were not modified. The male sexual behavior was impaired by prenatal LPS. Particularly the number of ejaculating animals was reduced. The testis weight was also lower in the prenatally LPS-treated rats than in the control rats. Conclusion: We propose that prenatal LPS exposure on GD21 acts as an imprinting factor that interferes with the programming of brain sexual determination in offspring. Copyright (C) 2009 S. Karger AG, Basel

Xenooplasmic Transfer between Buffalo and Bovine Enables Development of Homoplasmic Offspring

Nuclear-mitochondrial incompatibilities may be responsible for the development failure reported in embryos and fetuses produced by interspecies somatic cell nuclear transfer (iSCNT). Herein we performed xenooplasmic transfer (XOT) by introducing 10 to 15% of buffalo ooplasm into bovine zygotes to assess its effect on the persistence of buffalo mitochondrial DNA (mtDNA). Blastocyst rates were not compromised by XOT in comparison to both in vitro fertilized embryos and embryos produced by transfer of bovine ooplasm into bovine zygotes. Moreover, offspring were born after transfer of XOT embryos to recipient cows. Buffalo mtDNA introduced in zygotes was still present at the blastocyst stage (8.3 vs. 9.3%, p = 0.11), indicating unaltered heteroplasmy during early development. Nonetheless, no vestige of buffalo mtDNA was found in offspring, indicating a drift to homoplasmy during later stages of development. In conclusion, we show that the buffalo mtDNA introduced by XOT into a bovine zygote do not compromise embryo development. On the other hand, buffalo mtDNA was not inherited by offspring indicating a possible failure in the process of interspecies mtDNA replication.

Effect of cantilever length and framework alloy on the stress distribution of mandibular-cantilevered implant-supported prostheses

The purpose of this in vitro study was to analyze the stress distribution on components of a mandibular-cantilevered implant-supported prosthesis with frameworks cast in cobalt-chromium (Co-Cr) or palladium-silver (Pd-Ag) alloys, according to the cantilever length. Frameworks were fabricated on (Co-Cr) and (Pd-Ag) alloys and screwed into standard abutments positioned on a master-cast containing five implant replicas. Two linear strain gauges were fixed on the mesial and distal aspects of each abutment to capture deformation. A vertical static load of 100 N was applied to the cantilever arm at the distances of 10, 15, and 20 mm from the center of the distal abutment and the absolute values of specific deformation were recorded. Different patterns of abutment deformation were observed according to the framework alloy. The Co-Cr alloy framework resulted in higher levels of abutment deformation than the silver-palladium alloy framework. Abutment deformation was higher with longer cantilever extensions. Physical properties of the alloys used for framework interfere with abutment deformations patterns. Excessively long cantilever extensions must be avoided. To cite this article:Jacques LB, Moura MS, Suedam V, Souza EAC, Rubo JH. Effect of cantilever length and framework alloy on the stress distribution of mandibular-cantilevered implant-supported prostheses.Clin. Oral Impl. Res. 20, 2009; 737-741.doi: 10.1111/j.1600-0501.2009.01712.x.

Effect of abutment`s height and framework alloy on the load distribution of mandibular cantilevered implant-supported prosthesis

In cantilevered implant-supported complete prosthesis, the abutments` different heights represent different lever arms to which the abutments are subjected resulting in deformation of the components, which in turn transmit the load to the adjacent bone. The purpose of this in vitro study was to quantitatively assess the deformation of abutments of different heights in mandibular cantilevered implant-supported complete prosthesis. A circular steel master cast with five perforations containing implant replicas (O3.75 mm) was used. Two groups were formed according to the types of alloy of the framework (CoCr or PdAg). Three frameworks were made for each group to be tested with 4, 5.5 and 7 mm abutments. A 100 N load was applied at a point 15 mm distal to the center of the terminal implant. Readings of the deformations generated on the mesial and distal aspects of the abutments were obtained with the use of strain gauges. Deformation caused by tension and compression was observed in all specimens with the terminal abutment taking most of the load. An increase in deformation was observed in the terminal abutment as the height was increased. The use of an alloy of higher elastic modulus (CoCr) also caused the abutment deformation to increase. Abutment`s height and framework alloy influence the deformation of abutments of mandibular cantilevered implant-supported prosthesis. To cite this article:Suedam V, Capello SouzaEA, Moura MS, Jacques LB, Rubo JH. Effect of abutment`s height and framework alloy on the load distribution of mandibular cantilevered implant-supported prosthesis. Clin. Oral Impl. Res. 20, 2009; 196-200.doi: 10.1111/j.1600-0501.2008.01609.x.