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1.
Arch Environ Contam Toxicol ; 86(3): 199-216, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598146

RESUMO

Global contamination of environments with lead (Pb) poses threats to many ecosystems and populations. While exposure to Pb is toxic at high concentrations, recent literature has shown that lower concentrations can also cause sublethal, deleterious effects. However, there remains relatively little causal investigation of how exposure to lower concentrations of environmental Pb affects ecologically important behaviors. Behaviors often represent first-line responses of an organism and its internal physiological, molecular, and genetic responses to a changing environment. Hence, better understanding how behaviors are influenced by pollutants such as Pb generates crucial information on how species are coping with the effects of pollution more broadly. To better understand the effects of sublethal Pb on behavior, we chronically exposed adult wild-caught, captive house sparrows (Passer domesticus) to Pb-exposed drinking water and quantified a suite of behavioral outcomes: takeoff flight performance, activity in a novel environment, and in-hand struggling and breathing rate while being handled by an experimenter. Compared to controls (un-exposed drinking water), sparrows exposed to environmentally relevant concentrations of Pb exhibited decreases in takeoff flight performance and reduced movements in a novel environment following 9-10 weeks of exposure. We interpret this suite of results to be consistent with Pb influencing fundamental neuro-muscular abilities, making it more difficult for exposed birds to mount faster movements and activities. It is likely that suppression of takeoff flight and reduced movements would increase the predation risk of similar birds in the wild; hence, we also conclude that the effects we observed could influence fitness outcomes for individuals and populations altering ecological interactions within more naturalistic settings.


Assuntos
Água Potável , Pardais , Humanos , Animais , Pardais/genética , Chumbo/toxicidade , Ecossistema
2.
Zootaxa ; 4455(1): 68-98, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30314221

RESUMO

Cobras are among the most widely known venomous snakes, and yet their taxonomy remains incompletely understood, particularly in Africa. Here, we use a combination of mitochondrial and nuclear gene sequences and morphological data to diagnose species limits within the African forest cobra, Naja (Boulengerina) melanoleuca. Mitochondrial DNA sequences reveal deep divergences within this taxon. Congruent patterns of variation in mtDNA, nuclear genes and morphology support the recognition of five separate species, confirming the species status of N. subfulva and N. peroescobari, and revealing two previously unnamed West African species, which are described as new: Naja (Boulengerina) guineensis sp. nov. Broadley, Trape, Chirio, Ineich Wüster, from the Upper Guinea forest of West Africa, and Naja (Boulengerina) savannula sp. nov. Broadley, Trape, Chirio Wüster, a banded form from the savanna-forest mosaic of the Guinea and Sudanian savannas of West Africa. The discovery of cryptic diversity in this iconic group highlights our limited understanding of tropical African biodiversity, hindering our ability to conserve it effectively.


Assuntos
Elapidae , Genes Mitocondriais , África , África Ocidental , Animais , Florestas , Naja
4.
Patient Educ Couns ; 100(7): 1374-1381, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28237522

RESUMO

OBJECTIVE: We developed and formatively evaluated a tablet-based decision support tool for use by women prior to a contraceptive counseling visit to help them engage in shared decision making regarding method selection. METHODS: Drawing upon formative work around women's preferences for contraceptive counseling and conceptual understanding of health care decision making, we iteratively developed a storyboard and then digital prototypes, based on best practices for decision support tool development. Pilot testing using both quantitative and qualitative data and cognitive testing was conducted. We obtained feedback from patient and provider advisory groups throughout the development process. RESULTS: Ninety-six percent of women who used the tool in pilot testing reported that it helped them choose a method, and qualitative interviews indicated acceptability of the tool's content and presentation. Compared to the control group, women who used the tool demonstrated trends toward increased likelihood of complete satisfaction with their method. Participant responses to cognitive testing were used in tool refinement. CONCLUSION: Our decision support tool appears acceptable to women in the family planning setting. PRACTICE IMPLICATIONS: Formative evaluation of the tool supports its utility among patients making contraceptive decisions, which can be further evaluated in a randomized controlled trial.


Assuntos
Comportamento de Escolha , Comportamento Contraceptivo/psicologia , Anticoncepção/métodos , Aconselhamento , Tomada de Decisões , Técnicas de Apoio para a Decisão , Inquéritos e Questionários/normas , Adolescente , Adulto , Cognição , Anticoncepção/psicologia , Anticoncepcionais , Dispositivos Anticoncepcionais , Feminino , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Preferência do Paciente , Pesquisa Qualitativa , Adulto Jovem
5.
Pediatr Neurol ; 26(3): 239-42, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11955936

RESUMO

Leigh syndrome is a heterogenous neurologic disease characterized by seizures, developmental delay, muscle weakness, respiratory abnormalities, optic abnormalities, including atrophy and ophthalmoplegia, and progressive cranial nerve degeneration with early onset in infants and children. Diagnosis can be confirmed by characteristic pathologic findings of necrosis in the basal ganglia, thalamus, and brainstem. Severe dysfunction of mitochondrial energy metabolism is generally present and involved in the etiology of this degenerative central nervous system disease. At the molecular level, a number of point mutations have been located in mitochondrial DNA genes, including ATPase6 and tRNA(Lys) genes, and in nuclear genes encoding subunits of oxidative enzymes, such as pyruvate dehydrogenase. Biochemically these mutations are responsible for enzymatic defects in either respiratory complexes (I, IV, or V) or pyruvate dehydrogenase. We describe here the first case of Leigh syndrome with marked depletion of mitochondrial DNA levels in skeletal muscle and abnormal activities in skeletal muscle of mitochondrial respiratory complexes I, III, IV, and V.


Assuntos
DNA Mitocondrial/metabolismo , Doença de Leigh/genética , Encéfalo/patologia , Complexo I de Transporte de Elétrons , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Recém-Nascido , Doença de Leigh/diagnóstico , Doença de Leigh/metabolismo , Doença de Leigh/patologia , Imageamento por Ressonância Magnética , Masculino , Mitocôndrias Musculares/enzimologia , Músculo Esquelético/metabolismo , NADH NADPH Oxirredutases/metabolismo
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