64 research outputs found

    Dental Occlusion in a Split Amazon Indigenous Population: Genetics Prevails over Environment

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    Background: Studies examining human and nonhuman primates have supported the hypothesis that the recent increase in the occurrence of misalignment of teeth and/or incorrect relation of dental arches, named dental malocclusion, is mainly attributed to the availability of a more processed diet and the reduced need for powerful masticatory action. For the first time on live human populations, genetic and tooth wear influences on occlusal variation were examined in a split indigenous population. The Arara-Iriri people are descendants of a single couple expelled from a larger village. In the resultant village, expansion occurred through the mating of close relatives, resulting in marked genetic cohesion with substantial genetic differences. Methodology/Principal Findings: Dental malocclusion, tooth wear and inbreeding coefficient were evaluated. The sample examined was composed of 176 individuals from both villages. Prevalence Ratio and descriptive differences in the outcomes frequency for each developmental stage of the dentition were considered. Statistical differences between the villages were examined using the chi-square test or Fisher’s exact statistic. Tooth wear and the inbreeding coefficient (F) between the villages was tested with Mann-Whitney statistics. All the statistics were performed using two-tailed distribution at p#0.05. The coefficient inbreeding (F) confirmed the frequent incestuous unions among the Arara-Iriri indigenous group. Despite the tooth wear similarities, we found a striking difference in occlusal patterns between the two Arara villages. In the original village, dental malocclusion was present in about one third of the population; whilst in the resultant village, the occurrence was almost doubled. Furthermore, the morphological characteristics of malocclusion were strongly different between the groups. Conclusions/Significance: Our findings downplay the widespread influence of tooth wear, a direct evidence of what an individual ate in the past, on occlusal variation of living human populations. They also suggest that genetics plays the most important role on dental malocclusion etiology

    Wdr74 Is Required for Blastocyst Formation in the Mouse

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    Preimplantation is a dynamic developmental period during which a combination of maternal and zygotic factors program the early embryo resulting in lineage specification and implantation. A reverse genetic RNAi screen in mouse embryos identified the WD Repeat Domain 74 gene (Wdr74) as being required for these critical first steps of mammalian development. Knockdown of Wdr74 results in embryos that develop normally until the morula stage but fail to form blastocysts or properly specify the inner cell mass and trophectoderm. In Wdr74-deficient embryos, we find activated Trp53-dependent apoptosis as well as a global reduction of RNA polymerase I, II and III transcripts. In Wdr74-deficient embryos blocking Trp53 function rescues blastocyst formation and lineage differentiation. These results indicate that Wdr74 is required for RNA transcription, processing and/or stability during preimplantation development and is an essential gene in the mouse

    Oral health status of the ethnic group Xukuru from Ororubá: multilevel analysis

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    Objective: To analyse the oral health status of the indigenous people Xukuru from Ororubá aged 10 to 14 years old, in Pernambuco, Brazil. Method: A cross-sectional population-based study developed within the limits of the Indigenous Land Xukuru, from January to March 2010. Oral examinations were performed on a sample of 233 indigenous people. The software SPSS 13.0® was used for descriptive analysis. Later, in order to measure the effect of factors associated with the absence of caries, Poisson log-linear multilevel models were tested with the statistical software MLwiN 2.02®. Results: Oral examinations identified a DMFT Index average of 2.38 (± 2.62). Among all individuals examined, 26.61% were caries free. Multiple regression analysis revealed a negative association between the absence of caries and the variables: higher average of people per household in the villages, higher number of residents per household, older age, male sex, not knowing how to read and write, and very dissatisfied/dissatisfied with teeth/mouth. The variables higher income per capita, not sleeping due to dental problems, had never been to the dentist, no occurrence of toothache, and no need for dental treatment were positively associated with the absence of caries. Conclusion: The absence of caries is associated with contextual and individual factors of the indigenous people Xukuru from Ororubá, aged 10 to 14 years old

    The catatonic dilemma expanded

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    Catatonia is a common syndrome that was first described in the literature by Karl Kahlbaum in 1874. The literature is still developing and remains unclear on many issues, especially classification, diagnosis, and pathophysiology. Clinicians caring for psychiatric patients with catatonic syndromes continue to face many dilemmas in diagnosis and treatment. We discuss many of the common problems encountered in the care of a catatonic patient, and discuss each problem with a review of the literature. Focus is on practical aspects of classification, epidemiology, differential diagnosis, treatment, medical comorbidity, cognition, emotion, prognosis, and areas for future research in catatonic syndromes
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