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1.
J Hum Evol ; 94: 28-44, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27178456

RESUMO

Most Plio-Pleistocene sites in the Gregory Rift Valley that have yielded abundant fossil hominins lie on the Rift Valley floor. Here we report a new Pliocene site, Kantis, on the shoulder of the Gregory Rift Valley, which extends the geographical range of Australopithecus afarensis to the highlands of Kenya. This species, known from sites in Ethiopia, Tanzania, and possibly Kenya, is believed to be adapted to a wide spectrum of habitats, from open grassland to woodland. The Kantis fauna is generally similar to that reported from other contemporaneous A. afarensis sites on the Rift Valley floor. However, its faunal composition and stable carbon isotopic data from dental enamel suggest a stronger C4 environment than that present at those sites. Although the Gregory Rift Valley has been the focus of paleontologists' attention for many years, surveys of the Rift shoulder may provide new perspective on African Pliocene mammal and hominin evolution.


Assuntos
Distribuição Animal , Evolução Biológica , Fósseis , Hominidae/fisiologia , Animais , Meio Ambiente , Geologia , Quênia
3.
Front Immunol ; 13: 1008220, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341392

RESUMO

Human cytomegalovirus (HCMV) infections develop into CMV diseases that result in various forms of manifestations in local organs. CMV-retinitis is a form of CMV disease that develops in immunocompromised hosts with CMV-viremia after viruses in the peripheral circulation have entered the eye. In the HCMV genome, extensive diversification of the UL40 gene has produced peptide sequences that modulate NK cell effector functions when loaded onto HLA-E and are subsequently recognized by the NKG2A and NKG2C receptors. Notably, some HCMV strains carry UL40 genes that encode peptide sequences identical to the signal peptide sequences of specific HLA-A and HLA-C allotypes, which enables these CMV strains to escape HLA-E-restricted CD8+T cell responses. Variations in UL40 sequences have been studied mainly in the peripheral blood of CMV-viremia cases. In this study, we sought to investigate how ocular CMV disease develops from CMV infections. CMV gene sequences were compared between the intraocular fluids and peripheral blood of 77 clinical cases. UL40 signal peptide sequences were more diverse, and multiple sequences were typically present in CMV-viremia blood compared to intraocular fluid. Significantly stronger NK cell suppression was induced by UL40-derived peptides from intraocular HCMV compared to those identified only in peripheral blood. HCMV present in intraocular fluids were limited to those carrying a UL40 peptide sequence corresponding to the leader peptide sequence of the host's HLA class I, while UL40-derived peptides from HCMV found only in the peripheral blood were disparate from any HLA class I allotype. Overall, our analyses of CMV-retinitis inferred that specific HCMV strains with UL40 signal sequences matching the host's HLA signal peptide sequences were those that crossed the blood-ocular barrier to enter the intraocular space. UL40 peptide repertoires were the same in the intraocular fluids of all ocular CMV diseases, regardless of host immune status, implying that virus type is likely to be a common determinant in ocular CMV disease development. We thus propose a mechanism for ocular CMV disease development, in which particular HCMV types in the blood exploit peripheral and central HLA-E-mediated tolerance mechanisms and, thus, escape the antivirus responses of both innate and adaptive immunity.


Assuntos
Infecções por Citomegalovirus , Retinite , Humanos , Citomegalovirus , Viremia , Tolerância Central , Proteínas Virais , Imunidade Adaptativa , Peptídeos , Sinais Direcionadores de Proteínas , Antígenos HLA-E
4.
J AAPOS ; 22(5): 401-403.e1, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30120985

RESUMO

Pierson syndrome, an autosomal recessive disorder caused by a mutation in laminin ß2 (LAMB2) gene, is characterized by congenital nephrotic syndrome and various ocular abnormalities. The ocular findings in Pierson syndrome are not well understood, because the incidence of this syndrome is very rare. We report ocular findings in a 5-month-old boy with Pierson syndrome with a novel mutation in LAMB2. We performed a pupilloplasty for his microcoria. Ophthalmic examinations after surgery revealed that he had cataract, severe retinal degeneration, and high myopia. Optical coherence tomography showed the collapse of retinal layer structures and a marked decrease of choroidal thickness. Immunohistochemistry and electron microscopy examinations revealed abnormal iris differentiation and thinning or defect of basal membranes. These results suggest that the development of the iris, lens, retina, and choroid are affected in this type of mutation.


Assuntos
Anormalidades Múltiplas , Catarata/patologia , Anormalidades do Olho , Laminina/genética , Mutação , Miopia Degenerativa/patologia , Síndrome Nefrótica , Distúrbios Pupilares , Degeneração Retiniana/patologia , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Humanos , Lactente , Masculino , Síndromes Miastênicas Congênitas , Síndrome Nefrótica/genética , Síndrome Nefrótica/patologia , Distúrbios Pupilares/genética , Distúrbios Pupilares/patologia
5.
Rev. bras. oftalmol ; 80(5): e0039, 2021. tab, graf
Artigo em Português | LILACS | ID: biblio-1347255

RESUMO

RESUMO Objetivo Verificar a prevalência e as principais causas de baixa acuidade visual encontradas em estudantes; resolver as alterações refracionais por meio de correção óptica e estabelecer uma relação entre visão e desempenho escolar. Métodos Estudo transversal, quantitativo, de ação social realizada em uma escola pública de ensino fundamental e médio de Araçatuba (SP). A avaliação especializada foi indicada aos estudantes que, em triagem visual, apresentaram acuidade visual ≤0,7 em um ou em ambos os olhos, com ou sem correção óptica prévia. Foram entregues óculos a todos que necessitavam, para melhorar visão. Foi realizada análise pela ficha de atendimento e pela nota escolar dos alunos, pelos programas Excel e BioEstat. Resultados Dos 503 alunos triados, 75 (15%) apresentaram baixa de acuidade visual. Compareceram à consulta agendada 66 (88%), e 50 (80,65%) receberam óculos prontos. A média de idade foi de 152 anos, e houve predominância do sexo feminino (64,5%). As alterações refracionais foram a principal causa da baixa visual (90,3%), e miopia, associada ou não a astigmatismo, foi a mais prevalente (63%). Dentre os casos, 13 (21%) tinham anisometropia. Não houve diferença estatisticamente significativa (p=0,5479) entre as médias anuais dos alunos com baixa de acuidade visual e aqueles com visão normal. Conclusão Projetos sociais de triagem visual são facilmente executáveis, têm baixo custo e alta resolutividade, uma vez que os transtornos refracionais são a principal causa e facilmente corrigidos com óculos. A baixa de acuidade visual detectada nos alunos não interferiu no desempenho escolar.


ABSTRACT Objective To verify the prevalence and the main causes of low visual acuity among students, to correct refractive errors with eyewear, and to establish a relation between vision and school performance. Methods This is a cross-sectional, quantitative study of a social action carried out in a public elementary and high school in the city of Araçatuba (SP). Specialized evaluation was indicated to students who presented visual acuity ≤0.7 in one or both eyes, with or without prior optical correction, upon triage. Glasses were delivered to everyone who needed better vision. The analysis was performed based on screening record and student's school grade, using Excel and BioEstat software. Results Out of 503 students screened, 75 (15%) presented low visual acuity. Sixty-six (88%) attended the scheduled visit and 50 (80.65%) received ready-made glasses. The mean age was 15±2 years, and there was a predominance of females (64.5%). Refractive errors were the main cause of visual impairment (90.3%) and myopia, associated or not to astigmatism, was the most prevalent condition (63%). Thirteen (21%) students had anisometropia. There was no statistically significant difference (p=0.5479) in annual average grade of students with low visual acuity and those with normal vision. Conclusion Social projects for visual triage are carried out without effort, have a low cost and high problem-solving capacity, since refractive errors are the most frequent diagnoses and easily corrected with glasses. The low visual acuity detected in students did not interfere in their school performance.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Erros de Refração/complicações , Erros de Refração/diagnóstico , Serviços de Saúde Escolar , Transtornos da Visão/diagnóstico , Acuidade Visual , Saúde Ocular , Transtornos da Visão/reabilitação , Testes Visuais , Seleção Visual , Saúde do Estudante , Estudos Transversais , Diagnóstico Precoce , Óculos , Estudo Observacional
6.
Appl Spectrosc ; 66(6): 673-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22732538

RESUMO

This study explored the feasibility of rapid, nondestructive near-infrared (NIR) reflection spectroscopy for the prediction of conventional physical properties, carbon-nitrogen-sulfur (CNS) analysis, and concentration of inorganic components in sediment cores from a brackish lake. A long core sample, which consisted of well-preserved annually formed lamina from Lake Ogawara along the Pacific coast in Aomori Prefecture, northeastern Japan, was used to investigate the past environmental record. The core was previously analyzed for physical properties, CNS, and inorganic components. Calibration models were developed from NIR reflection spectra of 149 core samples. Partial least squares (PLS) analysis provided good regression models between measured and predicted values for water content, total nitrogen (TN), total organic carbon (TOC), total sulfur (TS), Al(2)O(3), S/Al(2)O(3), Fe(2)O(3)/Al(2)O(3), Sc/Al(2)O(3), Cu/Al(2)O(3), and Zn/Al(2)O(3) with coefficients of determination (r(2)) for cross-validation of 0.73, 0.89, 0.88, 0.73, 0.92, 0.81, 0.82, 0.75, 0.82, and 0.82, respectively. The variation of predicted component values as a function of depth showed the same trend as that of conventionally measured values. This study also showed the possibility of NIR spectroscopy as an on-site, rapid analytical tool for the identification of tephra (fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism), which is important for dating.

7.
Appl Opt ; 41(12): 2349-54, 2002 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-12003229

RESUMO

Two optical methods, cavity ring-down spectroscopy and photoacoustic spectroscopy, are applied to the measurement of the isotope ratio 18O/16O in water-vapor samples with a Nd3+:YAG pumped-dye laser. The combination band of (2v1 + v3) in the 960-nm region of water molecules is investigated for two standard water samples, the Vienna Standard Mean Ocean Water and the Standard Light Antarctic Precipitation. The results demonstrate that the two methods have the potential of compact systems for in-situ measurements of H2O isotope ratio in the environment.

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