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1.
J Helminthol ; 93(5): 616-628, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30231945

RESUMO

Despite the advances of molecular tools, new nematode species are still described mainly based on morphological characters. Parapharyngodon and Thelandros are two genera of oxyurids with unclear related taxonomic histories. Here we use morphological characters (linear measurements and categorical variables) and genetic information (18S rRNA, 28S rRNA and COI partial gene sequences) to confirm the relationships between representatives of these two genera and to determine whether they can be discriminated morphologically. Genetic results confirm the existence of two main clades, mostly congruent with Parapharyngodon and Thelandros genera but with several discordances. Thelandros is polyphyletic, with two of the species analysed (T. filiformis and T. tinerfensis) being part of the Thelandros clade, but with a third one (T. galloti) falling within the Parapharyngodon clade. Regarding the Parapharyngodon clade, P. cubensis, P. scleratus and Parapharyngodon sp. from Mexico form congruent lineages, while most P. echinatus samples cluster in another group, with one exception. Interestingly, P. micipsae samples are scattered across the Parapharyngodon clade, suggesting that they were misidentified or rather represent alternative morphotypes of other species. Morphological analysis identified the length of the tail, number of caudal papillae, position of the nerve ring, presence of caudal alae and length of the lateral alae as reliable characters to distinguish between Parapharyngodon and Thelandros genetic clades. Our study highlights the current taxonomic inconsistency in these groups, mainly derived from the exclusive use of morphological data. As such, we advocate for the routine implementation of molecular data in nematode taxonomic studies.


Assuntos
Oxyuroidea/classificação , Filogenia , Animais , DNA de Helmintos , Feminino , Lagartos/parasitologia , Masculino , México , Oxiuríase/parasitologia , Oxyuroidea/anatomia & histologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
2.
Health Care Women Int ; 22(3): 281-98, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11814073

RESUMO

The relationship between ethnocultural identity, eating practices, and cultural expectations is complex. When there are conflicting cultural demands, eating disturbances can occur. These disturbances affect many aspects of a woman's life, including her quality of life, health, relationships, and academic/career success. Contextual variables that may influence eating disorders in women of color include (a) level of acculturation, (b) socioeconomic status (SES), (c) peer socialization, (d) family structure, and (e) immigration status. This study examined these variables in a college sample of 115 Mexican American women. Each completed a demographic questionnaire and standardized instruments to measure acculturation, eating disorder symptoms, and family issues. Multiple regression analysis indicated that family rigidity contributes to an increased susceptibility for bulimic symptoms (p < .0001). Poor peer socialization and family rigidity were related to the preoccupation with body size and slimness, thus placing young Mexican American women at greater risk for developing self-destructive eating patterns such as severe weight control and dieting behaviors (p < .0001). Implications for health, quality of life, and appropriate therapeutic care are discussed.


Assuntos
Anorexia Nervosa/etnologia , Bulimia/etnologia , Americanos Mexicanos/psicologia , Estudantes/psicologia , Universidades , Mulheres/psicologia , Aculturação , Adolescente , Adulto , Anorexia Nervosa/diagnóstico , Anorexia Nervosa/etiologia , Anorexia Nervosa/terapia , Atitude Frente a Saúde/etnologia , Imagem Corporal , Bulimia/diagnóstico , Bulimia/etiologia , Bulimia/terapia , California , Escolaridade , Emigração e Imigração , Família/psicologia , Feminino , Humanos , Relações Interpessoais , Pessoa de Meia-Idade , Pesquisa Metodológica em Enfermagem , Grupo Associado , Socialização , Fatores Socioeconômicos , Inquéritos e Questionários
3.
Mol Phylogenet Evol ; 10(1): 37-48, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9751916

RESUMO

Data derived from the morphology of the seven species of South African sand lizards, Meroles (Reptilia, Lacertidae), and their outgroups produce a robust estimate of phylogeny when a maximum parsimony approach is applied. The estimate is fully resolved with little character conflict and internal branches are relatively long. This analysis indicates that Meroles is a true clade that includes the aberrant lacertid long separated as Aporosaura anchietae. The tree is pectinate, its successive external branches representing species with increasing adaptation to desert conditions, especially aeolian sand habitats. This pattern, and the robustness of the tree, support a model of invasion of severe habitats in which successive rounds of speciation, displacement, and adaptation result in spread into extreme ecological situations. To test the robust morphological phylogeny and, indirectly, the model as well, DNA from mitochondrial 12S and 16S ribosomal genes was sequenced and analyzed by both maximum parsimony and maximum likelihood approaches. Trees produced were largely congruent with that derived from morphology, although different from ones resulting from protein electrophoresis. However, in contrast to the internal branches of the morphological tree, those of the DNA maximum likelihood tree are quite short. The DNA data provide some corroboration for the relationships within Meroles based on morphology and consequently for the model as well. The disparity in internal branch lengths between the maximum parsimony morphological and maximum likelihood DNA trees may well indicate that the multiple adaptations to desert conditions arising on the main lineage of Meroles evolved quite rapidly. In this study DNA thus not only corroborates the phylogeny but also provides evidence about another aspect of evolutionary history.


Assuntos
Evolução Biológica , Lagartos/classificação , Mitocôndrias/genética , Adaptação Fisiológica , Animais , Sequência de Bases , Evolução Molecular , Lagartos/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , América do Sul
4.
J Pediatr ; 120(6): 899-905, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1317418

RESUMO

To investigate the biochemical nature of nephrocalcinosis in children with hypophosphatemic rickets treated with orally administered phosphate and vitamin D, we studied five such patients, aged 3.7 to 12.3 years, during treatment and again 3 days after it had been discontinued. Treatment was associated with significant increases in mean serum phosphate concentration and urine phosphate/creatinine ratio, from 0.71 to 1.03 mmol/L and from 3.61 to 9.42 mmol/mmol, respectively. Significant correlation was found between urine phosphate/creatinine and oxalate/creatinine ratios (r = 0.670; p less than 0.01); however, the mean urine oxalate/creatinine ratio of 65.0 mumol/mmol while patients were taking phosphate orally was not significantly different from the ratio of 59.0 mumol/mmol when treatment was discontinued. Kidney biopsy specimens from three of the patients showed that the renal calcifications were located mainly intratubularly and were composed exclusively of calcium phosphate. In a further investigation of the nature of phosphate-induced nephrocalcinosis, six 6-week-old male Hyp mice, the murine analog of the human disease, received oral phosphate therapy with drinking water for 48 days; six others served as control animals. Mice in the experimental group excreted more phosphate (p less than 0.001) and less calcium (p less than 0.01) than control mice did, and medullary nephrocalcinosis, with a high kidney calcium content, developed (p less than 0.001). Histologic sections showed that the renal calcifications were located intratubularly and were composed of calcium phosphate. We conclude that, both in children with hypophosphatemic rickets and in the Hyp mouse, the development of nephrocalcinosis is associated with high oral phosphate intake and subsequent deposition of calcium phosphate precipitates in the kidney.


Assuntos
Calcitriol/uso terapêutico , Hipofosfatemia Familiar/complicações , Rim/química , Nefrocalcinose/etiologia , Fosfatos/uso terapêutico , Animais , Fosfatos de Cálcio/análise , Criança , Feminino , Humanos , Hipofosfatemia Familiar/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos , Nefrocalcinose/metabolismo , Nefrocalcinose/patologia
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