HEPATITIS B VACCINATION COVERAGE AND POSTVACCINATION SEROLOGIC TESTING AMONG MEDICAL STUDENTS AT A PUBLIC UNIVERSITY IN BRAZIL

The aim of this cross-sectional study was to determine the hepatitis B vaccination coverage among medical students at a public university in Rio de Janeiro, Brazil, and their compliance with the postvaccination serologic testing recommendations. Of the total of 858 students, 675 (78.7%) participated in the study. Among the participants, 48.9% (95% CI: 45.1% to 52.7%) were vaccinated against hepatitis B (received ≥ 3 doses of the vaccine), 31.6% were not (received 0, 1 or 2 doses), and 19.6% did not know their vaccination status. Hepatitis B vaccination coverage increased from 26.0% among first-year students to 70.6% among sixth-year students while the prevalence of unknown vaccination status decreased from 39.7% among first-year students to 2.4% among sixth-year students. The frequency of unvaccinated students ranged from 23.7% among fifth-year students to 34.4% among first-year students. Only 34.8% of the vaccinated students performed the anti-HBs testing after vaccination. Among these medical students, we found a low adherence to the hepatitis B vaccination and to the postvaccination serologic testing. A comprehensive hepatitis B immunization program should be offered to students at this medical school.     

Analysis of male reproductive parameters in a murine model of mucopolysaccharidosis type I (MPS I)

Mucopolysaccharidosis (MPS) I is a lysosomal storage disorder (LSD) that is characterised by alpha-L-iduronidase (Idua) deficiency and continuous deposition of glycosaminoglycans (GAGs), which consequently interferes with cell signalling mechanisms and results in multisystemic and progressive symptoms. The animal model of MPS I (Idua-/-) has been widely studied to elucidate the consequences and progression of the disorder; however, studies specifically assessing the male reproductive tract are lacking. The aim of this study was to evaluate some of the reproductive characteristics of male MPS I mice in two phases of life. Reproductive organ biometry, sperm counts, sperm morphological evaluation, plasma testosterone measurements and histopathological, histomorphometrical and immunohistochemical analysis were performed in 3- and 6-month-old C57BL/6 Idua+/+ and Idua-/- mice. Seminal vesicle weights were decreased in both the 3- and 6-month-old Idua-/- mice. Decrease in sperm counts and the majority of the histopathological signs were observed in the 6-month-old Idua-/- mice. No differences were detected in the sperm morphological analysis. Immunohistochemistry revealed that seminiferous tubules from 3-month-old Idua-/- mice were more intensely stained with anti-caspase-3 than 3-month-old Idua+/+ mice, but no difference was found at 6 months. These results suggest that MPS I interferes with male reproductive parameters both in 3 and 6-month-old animals and histopathological signs are more pronounced in 6-month-old mice, indicating that the effects of the disorder may intensify with the disease progression.     

Mechanical and physical properties of silorane and methacrylate-based composites

ObjectivesThis study measured the degree of conversion (DC), sorption, solubility and microhardness of methacrylate (Filtek Z250 and Filtek Z350XT) and silorane-based composites (Filtek P90).MethodsDC was measured using near infrared spectroscopy immediately and 24 h after the photoactivation. Sorption and solubility measurements were performed after 24 h, 4 weeks and 12 weeks of storage in water. Knoop microhardness was measured after 24 h and after thermal cycling. The data were statistically analyzed using ANOVA followed by Tukey's, Tamhane or paired t-tests (α = 0.05).ResultsThe DC for P90 (37.22 ± 1.46) was significantly lower than the Z250 (71.44 ± 1.66) and Z350 (71.76 ± 2.84). Water sorption was highest in the Z250 and lowest in the P90. All the tested composites exhibited similar values after 24 h of immersion, and no significant differences were observed. No significant differences were observed between the solubilities of the P90 composite (12 weeks) and the Z250 or Z350 composites (4 weeks). KHN values were less elevated for the P90 composite and similar for the Z250 and Z350 composites. An effect of thermal cycling on KHN values was observed for all the composites (p < 0.001).ConclusionsSilorane produced the lowest DC and KHN values and exhibited lower water sorption and solubility compared to methacrylate-based composites. These differences suggest that silorane composites exhibit better hydrolytic stability after 3 months of water immersion compared to conventional methacrylate-based composites.Clinical significanceSilorane had higher hydrolytic stability after 3 months of water immersion than the methacrylate-based resins, despite the lower values of DC and KHN recorded.     

Maternal education level and low birth weight: a meta-analysis

ObjectiveTo assess the association between maternal education level and birth weight, considering the circumstances in which the excess use of technology in healthcare, as well as the scarcity of these resources, may result in similar outcomes.MethodsA meta-analysis of cohort and cross-sectional studies was performed; the studies were selected by systematic review in the MEDLINE database using the following Key**words socioeconomic factors, infant, low birth weight, cohort studies, cross-sectional studies. The summary measures of effect were obtained by random effect model, and its results were obtained through forest plot graphs. The publication bias was assessed by Egger's test, and the Newcastle-Ottawa scale was used to assess study quality.ResultsThe initial search found 729 articles. Of these, 594 were excluded after reading the title and abstract; 21, after consensus meetings among the three reviewers; 102, after reading the full text; and three for not having the proper outcome. Of the nine final articles, 88.8% had quality ≥ six stars (Newcastle-Ottawa Scale), showing good quality studies. The heterogeneity of the articles was considered moderate. High maternal education showed a 33% protective effect against low birth weight, whereas medium degree of education showed no significant protection when compared to low maternal education.ConclusionsThe hypothesis of similarity between the extreme degrees of social distribution, translated by maternal education level in relation to the proportion of low birth weight, was not confirmed.