The Winchcombe meteorite, a unique and pristine witness from the outer solar system.

Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth's water

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson’s disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

The genetic architecture of the human cerebral cortex

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 306 nominally genome-wide significant loci (P < 5 × 10−8) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 299 loci for which replication data were available, 241 loci influencing surface area and 14 influencing thickness remained significant after replication, with 199 loci passing multiple testing correction (P < 8.3 × 10−10; 187 influencing surface area and 12 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation (rG = −0.32, SE = 0.05, P = 6.5 × 10−12), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 10 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Oral presentation of 10 patients with Cowden syndrome

Cowden syndrome (CS) is an autosomal dominant genodermatosis that frequently affects several tissues with hamartomatous growth. The oral cavity is quite commonly involved with papillomatous lesions, which can be crucial to early diagnosis of this disease. In this series, 10 patients with a great diversity of manifestations associated with CS are presented, in whom oral papillomatosis was a constant and relevant finding to establish the diagnosis of CS. The role of the dentist in recognizing the oral lesions, the other diagnostic criteria, the risk for the development of malignancies, and the importance of lifetime follow-up are discussed.1174E301E31

Hard palate hyperpigmentation secondary to chronic chloroquine therapy: report of five cases

Antimalarials are commonly prescribed in medical practice for conditions such as rheumatoid arthritis, lupus erythematosus, as well as malaria. They are generally well-tolerated, but side effects, although infrequent, are well known. The antimalarial chloroquine diphosphate may be associated with a bluish-gray to black hyperpigmentation of the oral mucosa, mainly on the hard palate. In this report we described five additional cases of palate hyperpigmentation related to the chronic use of chloroquine diphosphate. Professionals must be aware of the adverse effects of antimalarials as chloroquine diphosphate in order to make the correct diagnosis and appropriate management of the patient. Early diagnosis of oral pigmentation by antimalarials may be of great relevance, because it might be an early sign of ocular involvement, and therefore it may be helpful to prevent further complications of antimalarial therapy for the patient.40983383

Adolescência, comportamento sexual e fatores de risco à saúde

OBJETIVO : Analisar a rela&#231;&#227;o entre comportamento sexual e fatores de risco &#224; sa&#250;de f&#237;sica ou mental entre adolescentes. M&#201;TODOS : Estudo realizado com 3.195 escolares de 15 a 19 anos de idade, do segundo ano do ensino m&#233;dio de escolas p&#250;blicas e particulares das capitais de 10 estados do Brasil, em 2007-2008. Foi utilizada amostragem por conglomerados com multiest&#225;gio de sele&#231;&#227;o (escolas e alunos) em cada cidade e rede de ensino p&#250;blica e particular. Foi aplicado question&#225;rio a todos os alunos selecionados, com os seguintes itens: dados socioecon&#244;micos e demogr&#225;ficos; comportamento sexual; &#8220;transar&#8221; com pessoas do mesmo sexo, do sexo oposto ou de ambos os sexos; uso de bebida alco&#243;lica e maconha; usar camisinha ao &#8220;transar&#8221;; presen&#231;a de experi&#234;ncias sexuais traum&#225;ticas na inf&#226;ncia ou adolesc&#234;ncia; e idea&#231;&#227;o suicida. A an&#225;lise incluiu descri&#231;&#227;o de frequ&#234;ncias, teste de Qui-quadrado, an&#225;lise de correspond&#234;ncia m&#250;ltipla e de cluster. Foram analisadas qualitativamente, por an&#225;lise dos conte&#250;dos manifestos, as respostas a uma quest&#227;o livre em que o adolescente expressou coment&#225;rios gerais sobre si e sua vida. RESULTADOS : Cerca de 3,0% dos adolescentes referiu comportamento homossexual ou bissexual, sem diferencia&#231;&#227;o de sexo, idade, cor da pele, estrato social, estrutura familiar e rede de ensino. Adolescentes com comportamento homo/bissexual comparados aos heterossexuais relataram (p < 0,05): ficar de &#8220;porre&#8221; (18,7% e 10,5%, respectivamente), uso frequente de maconha (6,1% e 2,1%, respectivamente), idea&#231;&#227;o suicida (42,5% e 18,7%, respectivamente) e ter sido v&#237;tima de viol&#234;ncia sexual (11,7% e 1,5%; respectivamente). Adolescentes com comportamento homo/bissexual relataram utilizar menos preservativo de forma frequente (74,2%) do que aqueles com comportamento heterossexual (48,6%, p < 0,001). Tr&#234;s grupos foram encontrados na an&#225;lise de correspond&#234;ncia: composto por adolescentes com comportamento homo/bissexual e que vivenciava os fatores de risco: sofrer viol&#234;ncia sexual, nunca utilizar camisinha ao &#8220;transar&#8221;, idea&#231;&#227;o suicida, uso frequente de maconha; composto por usu&#225;rios ocasionais de maconha e camisinha e com frequentes &#8220;porres&#8221;; adolescentes com comportamento heterossexual e aus&#234;ncia dos fatores de risco investigados. Entre adolescentes com comportamento homo e bissexual, houve mais fatores de risco quando comparados &#224;queles com comportamento heterossexual. Os adolescentes com comportamento homo e bissexual expuseram mais suas viv&#234;ncias pessoais positivas e relacionamentos negativos do que seus pares heterossexuais, mas se expressaram menos sobre religiosidade. CONCLUS&#213;ES : O tema n&#227;o somente deve ser mais estudado como tamb&#233;m devem ser ampliadas as a&#231;&#245;es preventivas voltadas aos adolescentes com rela&#231;&#245;es afetivo-sexuais homo/bissexuais