966 resultados para Ancient ophthalmology


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Stroke was probably first described in Psalms 136: 5-6 of the Catholic Bible, and Psalms 137:5-6 of the Evangelical Bible. Based on the Portuguese, Spanish, English, German, Dutch, Russian, Greek, and original Hebrew Bible, the significance of this Psalm is the invocation of a punishment, of which the final result would be a stroke of the left middle cerebral artery, causing motor aphasia and right hemiparesis.

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Amphisbaenians are legless reptiles that differ significantly from other vertebrate lineages. Most species dig underground galleries of similar diameter to that of the animal. We studied the muscle physiology and morphological attributes of digging effort in the Brazilian amphisbaenid Leposternon microcephalum (Squamata; Amphisbaenia), which burrows by compressing soil against the upper wall of the tunnel by means of upward strokes of the head. The individuals tested (<72 g) exerted forces on the soil of up to 24 N. These forces were possible because the fibres of the longissimus dorsi, the main muscle associated with burrowing, are highly pennated, thus increasing effective muscle cross-sectional area. The muscle is characterized by a metabolic transition along its length: proximal, medial and distal fibres are fast contracting and moderately oxidative, but fibres closer to the head are richer in citrate synthase and more aerobic in nature. Distal fibres, then, might be active mainly at the final step of the compression stroke, which requires more power. For animals greater than a given diameter, the work required to compress soil increases exponentially with body diameter. Leposternon microcephalum, and probably some other highly specialized amphisbaenids, are most likely constrained to small diameters and can increase muscle mass and effective muscle cross-sectional area by increasing body length, not body diameter.

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Cutaneous biopsies (n = 94) obtained from 88 patients with American tegumentary leishmaniasis were studied by conventional and immunohistochemical techniques. Specimens were distributed as active lesions of cutaneous leishmaniasis (n = 53) (Group I), cicatricial lesions of cutaneous leishmaniasis (n = 35) (Group II) and suggestive scars of healed mucosal leishmaniasis patients (n = 6) (Group III). In addition, active cutaneous lesions of other etiology (n = 24) (Group C1) and cutaneous scars not related to leishmaniasis (n = 10) (Group C2) were also included in the protocol. Amastigotes in Group I biopsies were detected by routine histopathological exam (30.2%), imprint (28.2%), culture (43.4%), immunofluorescence (41.4%) and immunoperoxidase (58.5%) techniques; and by the five methods together (79.3%). In Group II, 5.7% of cultures were positive. Leishmanial antigen was also seen in the cytoplasm of macrophages and giant cells (cellular pattern), vessel walls (vascular pattern) and dermal nerves (neural pattern). Positive reaction was detected in 49 (92.5%), 20 (57%) and 4 (67%) biopsies of Groups I, II and III, respectively. Antigen persistency in cicatricial tissue may be related to immunoprotection or, on the contrary, to the development of late lesions. We suggest that the cellular, vascular and neural patterns could be applied in the immunodiagnosis of active and cicatricial lesions in which leishmaniasis is suspected.

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The chronicles of historical sources are difficult because they are a mix of myths and facts experienced by their authors. Starting from this premise, this study analyzes some of the Spanish and indigenous sources on the conquest of the Inca people and the description of this world and people who were so different. Among the chroniclers chosen, the article highlights the reports by Jose de Acosta on the Mundus Novus and by Cieza de Leon and Garcilaso de la Vega on the myths of the first Inca chief; finally, Francisco de Xerez, Juan de Betanzos, among others, on the event of the imprisonment and murder of Atahualpa, which resulted in the conquest of the "Tahuantinsuyu" by the Spanish.

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The Foxl2 (forkhead box L2) gene is an important member of the forkhead domain family, primarily responsible for the development of ovaries during female sex differentiation. The evolutionary studies conducted previously considered the presence of paralog Foxl2 copies only in teleosts. However, to search for possible paralog copies in other groups of vertebrates and ensure that all predicted copies were homolog to the Foxl2 gene, a broad evolutionary analysis was performed, based on the forkhead domain family. A total of 2464 sequences for the forkhead domain were recovered, and subsequently, 64 representative sequences for Foxl2 were used in the evolutionary analysis of this gene. The most important contribution of this study was the discovery of a new subgroup of Foxl2 copies (ortholog to Foxl2B) present in the chondrichthyan Callorhinchus milii, in the coelacanth Latimeria chalumnae, in the avian Taeniopygia guttata and in the marsupial Monodelphis domestica. This new scenario indicates a gene duplication event in an ancestor of gnathostomes. Furthermore, based on the analysis of the syntenic regions of both Foxl2 copies, the duplication event was not exclusive to Foxl2. Moreover, the duplicated copy distribution was shown to be complex across vertebrates, especially in tetrapods, and the results strongly support a loss of this copy in eutherian species. Finally, the scenario observed in this study suggests an update for Foxl2 gene nomenclature, extending the actual suggested teleost naming of Foxl2A and Foxl2B to all vertebrate sequences and contributing to the establishment of a new evolutionary context for the Foxl2 gene. © 2013 Macmillan Publishers Limited All rights reserved.

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Over the past two decades, several fungal outbreaks have occurred, including the high-profile 'Vancouver Island' and 'Pacific Northwest' outbreaks, caused by Cryptococcus gattii, which has affected hundreds of otherwise healthy humans and animals. Over the same time period, C. gattii was the cause of several additional case clusters at localities outside of the tropical and subtropical climate zones where the species normally occurs. In every case, the causative agent belongs to a previously rare genotype of C. gattii called AFLP6/VGII, but the origin of the outbreak clades remains enigmatic. Here we used phylogenetic and recombination analyses, based on AFLP and multiple MLST datasets, and coalescence gene genealogy to demonstrate that these outbreaks have arisen from a highly-recombining C. gattii population in the native rainforest of Northern Brazil. Thus the modern virulent C. gattii AFLP6/VGII outbreak lineages derived from mating events in South America and then dispersed to temperate regions where they cause serious infections in humans and animals.

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Canine transmissible venereal tumor (CTVT) is the oldest known somatic cell lineage. It is a transmissible cancer that propagates naturally in dogs. We sequenced the genomes of two CTVT tumors and found that CTVT has acquired 1.9 million somatic substitution mutations and bears evidence of exposure to ultraviolet light. CTVT is remarkably stable and lacks subclonal heterogeneity despite thousands of rearrangements, copy-number changes, and retrotransposon insertions. More than 10,000 genes carry nonsynonymous variants, and 646 genes have been lost. CTVT first arose in a dog with low genomic heterozygosity that may have lived about 11,000 years ago. The cancer spawned by this individual dispersed across continents about 500 years ago. Our results provide a genetic identikit of an ancient dog and demonstrate the robustness of mammalian somatic cells to survive for millennia despite a massive mutation burden.

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Liz Bryan begins her book with a description of the Canadian Plains:" . .. a voluptuous landscape of hills and valleys and plains, of lakes and tiny twinkling potholes, of flower-filled coulees and vast sand dunes." Her emphasis throughout on the landscape of southern Saskatchewan and Alberta is necessary since the ancient monuments she describes only truly resonate within this setting. Indeed, almost every page of this attractive book is adorned with at least two color images-of scenery, stone features, artifacts, and aboriginal events. She then proceeds to an eclectic overview of the archaeological record of the Plains of Saskatchewan and Alberta, including the earliest human evidence, such as the Clovis points from the Wally's Beach site, Alberta, where the trackways of mammoths, camels, and muskoxen were miraculously and briefly exposed in the late 1990s. There is one perplexing error, however-the attribution of the extinction of the ice age bestiary, about 12,000 years ago, to the meteorite that felled the dinosaurs!

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We use a recently developed computerized modeling technique to explore the long-term impacts of indigenous Amazonian hunting in the past, present, and future. The model redefines sustainability in spatial and temporal terms, a major advance over the static "sustainability indices" currently used to study hunting in tropical forests. We validate the model's projections against actual field data from two sites in contemporary Amazonia and use the model to assess various management scenarios for the future of Manu National Park in Peru. We then apply the model to two archaeological contexts, show how its results may resolve long-standing enigmas regarding native food taboos and primate biogeography, and reflect on the ancient history and future of indigenous people in the Amazon.

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Objective: To assess the waiting time for eye care identifying the number of patients with each complaint; to investigate how the waiting time may worsen the patient's condition; to check the screening of urgent cases for effectiveness; and to devise means of increasing the medical-surgical care capacity. Methods: A retrospective descriptive survey was conducted using data obtained on 12 occasions during collaborative team visits to provide eyecare services. These initiatives were designed to decrease the waiting time and to treat urgent cases that occurred on each occasion; eyecare services were provided every Saturday, in the period from June to August 2006, in 16 cities of the region covered by Conderg (Consortium for the Development of the Sao Joao da Boa Vista Administrative Region). Results: Referrals used 1,743 (87.1%) of the 2,000 places available. The most frequent diagnoses were refractive errors, with 683 cases, corresponding to 39.1% of the total, followed by cataracts, with 296 cases, corresponding to 20.9%. Of the 238 surgeries indicated, 54.6% were phakectomies. Thirty-five (2.0%) cases were considered urgent. Conclusion: The most common diagnoses made during the team visits to manage the excess demand for eyecare were refractive errors and cataracts, which, together, accounted for the majority of the cases. The Divinolandia Hospital has the necessary human and material resources to meet the demand left unattended by the local SUS network. Immediate referral of urgent cases by the primary units' screeners proved effective.

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Congenital gonadotropin-releasing hormone (GnRH) deficiency manifests as absent or incomplete sexual maturation and infertility. Although the disease exhibits marked locus and allelic heterogeneity, with the causal mutations being both rare and private, one causal mutation in the prokineticin receptor, PROKR2 L173R, appears unusually prevalent among GnRH-deficient patients of diverse geographic and ethnic origins. To track the genetic ancestry of PROKR2 L173R, haplotype mapping was performed in 22 unrelated patients with GnRH deficiency carrying L173R and their 30 first-degree relatives. The mutations age was estimated using a haplotype-decay model. Thirteen subjects were informative and in all of them the mutation was present on the same approximate to 123 kb haplotype whose population frequency is 10. Thus, PROKR2 L173R represents a founder mutation whose age is estimated at approximately 9000 years. Inheritance of PROKR2 L173R-associated GnRH deficiency was complex with highly variable penetrance among carriers, influenced by additional mutations in the other PROKR2 allele (recessive inheritance) or another gene (digenicity). The paradoxical identification of an ancient founder mutation that impairs reproduction has intriguing implications for the inheritance mechanisms of PROKR2 L173R-associated GnRH deficiency and for the relevant processes of evolutionary selection, including potential selective advantages of mutation carriers in genes affecting reproduction.