Modeling of post-traumatic epilepsy and experimental research aimed at its prevention

Research on the prevention of post-traumatic epilepsy (PTE) has seen remarkable advances regarding its physiopathology in recent years. From the search for biomarkers that might be used to indicate individual susceptibility to the development of new animal models and the investigation of new drugs, a great deal of knowledge has been amassed. Various groups have concentrated efforts in generating new animal models of traumatic brain injury (TBI) in an attempt to provide the means to further produce knowledge on the subject. Here we forward the hypothesis that restricting the search of biomarkers and of new drugs to prevent PTE by using only a limited set of TBI models might hamper the understanding of this relevant and yet not preventable medical condition.     

Genetic variation and relationships at six VNTR loci in two distinct sample populations in Brazil

Background: The Brazilian population has been the focus of intensive genetic study due to admixture characteristics whereas there are few reports on the variability of VNTR loci in Brazil.

Primary objective: The aim of this study was to analyse genetic parameters in sample populations from two geographically distant regions: São Luís City, in Maranhão State and Campinas City, in São Paulo State. We investigated if distinct colonization influences could produce detectable differences in genetic background.

Subject and methods: DNA samples from peripheral drained blood were obtained from unrelated individuals who underwent paternity testing. Allelic variation in six VNTR loci (D2S44, D4S139, D5S110, D8S358, D10S28 and D17S79) was evaluated. The results were compared to reference databases available for general Latin-derived European and African–American populations as well as for other Brazilian groups.

Results: This study reveals that forensic population parameters did not show differences among regions, although we detected admixture values varying between the south-east and north-east of Brazil.

Conclusions: Differences between the two samples are probably due to different admixture proportions of European- and African-derived alleles in each region; both populations are in Hardy–Weinberg equilibrium. In addition, the allelic frequency for all loci, in both populations, can be used as database for forensic purposes.     

Effects of short-term physical training on the liver IGF-I in diabetic rats

To investigate the influence of short-term physical training on IGF-I concentrations in diabetic rats, male wistar rats were distributed into four groups: sedentary control, trained control, sedentary diabetic and trained diabetic. Diabetes was induced by Alloxan (32 mg/kg b.w.) and training protocol consisted of swimming 1 h/day, 5 days/week, during 4 weeks, supporting 5% b.w. At the end of this period, rats were sacrificed and blood was collected for determinations of serum glucose, insulin, albumin, IGF-I and hematocrit. Liver samples were used to determine glycogen, protein, DNA and IGF-I concentrations. Diabetes reduced insulin and IGF-I concentrations in blood and liver protein, ratio protein/DNA and IGF-I concentrations in liver and increased glycemia. Physical training reduced serum glucose and recovered hepatic glycogen stores in diabetic rats and reduced serum and liver IGF-I concentrations. In conclusion, short-term physical training improved the metabolic conditions of diabetic rats, despite of impairing liver and blood IGF-I concentrations.     

Isolation of a phylogenetically distinct rabies virus from a tufted capuchin monkey (Cebus apella) in Brazil

A rabies virus isolate (BRmk1358 strain) was discovered from a rabid tufted capuchin monkey in Brazil. The present study determined the nucleotide sequence of the BRmk1358 strain and compared with the rabies viruses isolated from marmosets and other animals in the Americas. Phylogenetic analyses showed that the BRmk1358 strain formed a lineage distant from that of marmoset rabies virus within the Chiroptera-related rabies virus cluster. This result suggests that the source of rabies infection in the tufted capuchin monkey may have been bat, and that they have a risk to act as rabies reservoir in Brazil.     

Effect of cementation delay on bonding of self-adhesive resin cement to yttria-stabilized tetragonal zirconia polycrystal ceramic treated with nonthermal argon plasma

Statement of problemNonthermal argon plasma (NTAP) has been reported to improve the bond strength of resin cements to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics. However, the effect of the inevitable delay before cementation and after treating Y-TZP ceramics with NTAP is unclear.PurposeThe purpose of this in vitro study was to investigate whether delays of 8, 12, and 24 hours between the Y-TZP ceramic treatment with NTAP and the cementation would affect the surface energy and the bond strength of a self-adhesive resin cement to Y-TZP ceramic.Material and methodsSixty plates and 50 blocks of 3Y-TZP ceramic were divided into 2 groups (n=30 and n=25): as-sintered (AS) and airborne-particle abraded with 50-μm Al₂O₃ (APA). These groups were further divided into 5 subgroups (n=6 and n=5) according to the delay between the NTAP treatment and the measurement of surface energy and microtensile bond strength (μTBS) evaluation: (0, 8, 12, and 24 hours). For both 3Y-TZP surface conditions (AS and APA), a control group without NTAP treatment was used (ASC and APAC). The surface energy (SE) was evaluated with a goniometer and the 3Y-TZP elemental composition with X-ray photoelectron spectroscopy (XPS). For the μTBS test, the 3Y-TZP ceramic blocks were cemented to composite resin blocks with a self-adhesive resin cement. After storage in distilled water at 37 °C for 24 hours, the 3Y-TZP-composite resin blocks were sectioned into beams and submitted to a μTBS test. Data were submitted to 2-way ANOVA and the Tukey HSD test (α=.05).ResultsFor the AS group, NTAP increased the SE irrespective of the delay before measurement: ASC<0 hour=8 hours=12 hours=24 hours (P<.05). For the APA group, except after 12 hours, NTAP also increased the surface energy (P<.05). XPS analysis showed an increase in the oxygen/carbon ratio after NTAP treatment for both groups. For the AS group, NTAP increased the μTBS after 0, 8, and 12 hours (P<.05), whereas for the APA group this occurred only after 8 hours (P<.05). For the AS and APA groups, the highest μTBS was reached after 8 hours (P<.05).ConclusionsTreatment of 3Y-TZP ceramic with NTAP improved the SE and increased the μTBS of self-adhesive resin cement to 3Y-TZP ceramic. These effects were time dependent, with better results at 8 hours after NTAP treatment.     

Efficacy of a mouthwash containing 0.8% arginine,PVM/MA copolymer,pyrophosphates, and 0.05% sodium fluoride compared to a negative control mouthwash on dentin hypersensitivity reduction. A randomized clinical trial

ObjectiveThe objective of this eight week, single-center, two-cell, double-blind, and randomized clinical study was to evaluate the dentin hypersensitivity reduction efficacy of a mouthwash using Pro-Argin? Mouthwash Technology containing 0.8% arginine, PVM/MA copolymer, pyrophosphates, and 0.05% sodium fluoride in an alcohol-free base (“Arginine Mouthwash”) compared to an ordinary mouthwash without any active ingredients (“Negative Control”).MethodsQualifying subjects who presented two hypersensitive teeth with a tactile hypersensitivity score between 10 and 50 g of force, and an air blast hypersensitivity score of 2 or 3 participated in this study and were randomized into one of two treatment groups. Subjects brushed with the toothbrush and fluoride toothpaste provided and then rinsed with 20 mL of their assigned mouthwash for 30 s twice daily. Subjects refrained from eating or drinking for 30 min after rinsing. Dentin hypersensitivity assessments, as well as examinations of oral hard and soft tissues, were conducted at the baseline visit and again after two weeks, four weeks and eight weeks of product use.ResultsNinety (90) subjects entered and completed the eight week study. After two weeks, four weeks and eight weeks of product use, subjects in the Arginine Mouthwash group exhibited statistically significant (p < 0.05) improvements in mean tactile and air blast hypersensitivity scores as compared to the Negative Control Mouthwash.ConclusionThe results of this study support the conclusion that the Arginine Mouthwash provides a significant reduction in dentin hypersensitivity after eight weeks of product use as compared to a Negative Control mouthwash.