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1.
J Evol Biol ; 26(6): 1281-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23458151

RESUMO

Exaggerated male ornaments are predicted to be costly to their bearers, but these negative effects may be offset by the correlated evolution of compensatory traits. However, when locomotor systems, such as wings in flying species, evolve to decrease such costs, it remains unclear whether functional changes across related species are achieved via the same morphological route or via alternate changes that have similar function. We conducted a comparative analysis of wing shape in relation to eye-stalk elongation across 24 species of stalk-eyed flies, using geometric morphometrics to determine how species with increased eye span, a sexually selected trait, have modified wing morphology as a compensatory mechanism. Using traditional and phylogenetically informed multivariate analyses of shape in combination with phenotypic trajectory analysis, we found a strong phylogenetic signal in wing shape. However, dimorphic species possessed shifted wing veins with the result of lengthening and narrowing wings compared to monomorphic species. Dimorphic species also had changes that seem unrelated to wing size, but instead may govern wing flexion. Nevertheless, the lack of a uniform, compensatory pattern suggests that stalk-eyed flies used alternative modifications in wing structure to increase wing area and aspect ratio, thus taking divergent morphological routes to compensate for exaggerated eye stalks.


Assuntos
Evolução Biológica , Dípteros/anatomia & histologia , Filogenia , Asas de Animais/anatomia & histologia , Animais , Dípteros/classificação , Masculino
2.
Science ; 171(3971): 585-7, 1971 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-4321925

RESUMO

Linkage groups of a culicine mosquito, Culex tritaeniorhynchus, have been assigned to their respective chromosomes by genetic and cytologic observations of radiation-induced aberrations. Linkage group I is assigned to the smallest chromosome, linkage group II to the submetacentric chromosome, and linkage group III to the metacentric chromosome.


Assuntos
Cromossomos , Culex/citologia , Citogenética , Insetos Vetores/citologia , Animais , Aberrações Cromossômicas , Encefalite Japonesa , Ligação Genética , Infertilidade Masculina/genética , Cariotipagem , Masculino , Radiogenética , Cromossomos Sexuais , Testículo/citologia
3.
Genetics ; 71(2): 287-96, 1972 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-5065280

RESUMO

A natural population of Culex tritaeniorhynchus was sampled to test the efficacy of a proposed method to detect and measure concealed variability. Thirty-nine lethals and ten recessive visible mutations were uncovered out of a total of 125 chromosomes tested.


Assuntos
Culex , Variação Genética , Genética Populacional , Animais , Cromossomos , Cruzamentos Genéticos , Feminino , Genes Letais , Genes Recessivos , Heterozigoto , Homozigoto , Infertilidade , Masculino , Mutação , Fenótipo
4.
BMC Evol Biol ; 1: 6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11696235

RESUMO

BACKGROUND: Polytene chromosome banding patterns have long been used by Drosophila evolutionists to infer degree of relatedness among taxa. Recently, nucleotide sequences have preempted this traditional method. We place the classical Drosophila evolutionary biology tools of polytene chromosome inversion analysis in a phylogenetic context and assess their utility in comparison to nucleotide sequences. RESULTS: A simultaneous analysis framework was used to examine the congruence of the chromosomal inversion data with more recent DNA sequence data in four Drosophila species groups - the melanogaster, virilis, repleta, and picture wing. Inversions and nucleotides were highly congruent with one another based on incongruence length difference and partitioned Bremer support values. Inversion phylogenies were less resolved because of fewer numbers of characters. Partitioned Bremer supports, corrected for the number of characters in each matrix, were higher for inversion matrices. CONCLUSIONS: Polytene chromosome data are highly congruent with DNA sequence data and, when placed in a simultaneous analysis framework, are shown to be more information rich than nucleotide data.


Assuntos
Cromossomos , Drosophila/genética , Filogenia , Animais , Inversão Cromossômica , Cromossomos/genética , DNA/genética , Drosophila melanogaster/genética , Evolução Molecular , Genes de Insetos/genética , Análise de Sequência de DNA/métodos
5.
Evolution ; 55(7): 1373-85, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11525461

RESUMO

Eye stalks and their scaling relationship with body size are important features in the mating system of many diopsid species, and sexual selection is a critical force influencing the evolution of this exaggerated morphology. Interspecific variation in eye span suggests there has been significant evolutionary change in this trait, but a robust phylogenetic hypothesis is required to determine its rate and direction of change. In this study, the pattern of morphological evolution of eye span is assessed in a phylogenetic framework with respect to its function in the sexual system of these flies. Specifically, we examine within the family Diopsidae the pattern of increase and decrease in sexual dimorphism, the morphological coevolution of eye span between males and females, and the evolutionary flexibility of eye-span allometry. Based on several different methods for reconstructing morphological change, results suggest a general pattern of evolutionary flexibility, particularly for eye-span allometry. Sexual dimorphism in eye span has evolved independently at least four times in the family and this trait also has undergone several reductions within the genus Diasemopsis. Despite most species being dimorphic, there is a strong phylogenetic correlation between males and females for mean eye span. The coevolution between the sexes for eye-span allometry, however, is significantly weaker. Overall, eye-span allometry exhibits significantly more change on the phylogeny than the other morphological traits. The evolutionary pattern in eye-span allometry is caused primarily by changes in eye-span variance. Therefore, this pattern is consistent with recent models that predict a strong relationship between sexual selection and the variance of ornamental traits and highlights the significance of eye-span allometry in intersexual and intrasexual signaling.


Assuntos
Evolução Biológica , Dípteros/anatomia & histologia , Olho/anatomia & histologia , Filogenia , Caracteres Sexuais , Animais , Constituição Corporal , Dípteros/fisiologia , Feminino , Masculino , Modelos Biológicos , Comportamento Sexual Animal
6.
Am J Med Genet ; 31(2): 427-35, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2852900

RESUMO

Ophthalmic examinations were performed on 56 patients with validated familial adenomatous polyposis (FAP) for hyperpigmented defects of the retinal pigment epithelium. Such lesions were seen bilaterally in 29 patients (52%) and unilaterally in 8 patients (14%). Of the 56 patients, 33 had one or more of the extracolonic expressions associated with Gardner syndrome. We found retinal lesions in 8 patients without any of the expressions of Gardner syndrome. No association was found between Gardner syndrome and the retinal lesions when these patients were compared to patients without any stigmata of Gardner syndrome, nor was any significant association found when each of the expressions was compared individually with the presence of the pigmented retinal lesions. The presence or absence of eye findings were seen to cluster within families. There was no association with sex. Fundus lesions are apparently a variable expression of the FAP gene and are not specifically associated with Gardner syndrome.


Assuntos
Polipose Adenomatosa do Colo/patologia , Epitélio Pigmentado Ocular/patologia , Pigmentos da Retina/análise , Polipose Adenomatosa do Colo/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Am J Trop Med Hyg ; 33(4): 715-24, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6476219

RESUMO

Mutant and geographical strains of Culex tritaeniorhynchus were compared for West Nile (WN) virus susceptibility by feeding on a high-titered blood-virus suspension. Eleven strains also were selected from 2-21 generations for an increase and/or a reduction of oral susceptibility using 90% and 10% infective virus doses, respectively. Only one of the 20 strains tested, e ma, was significantly less susceptible than the control strain. In the selection experiments, none of the strains showed a consistent decrease in susceptibility, but the Changa Manga II (CM) strain showed a sustained increase in susceptibility from generations F11-F21 when selection was discontinued. Reciprocal cross-matings and back-crosses were set up between the selected CM strain and two of the morphological mutant strains, e ma and re e ae, carrying homozygous recessive markers. The resulting progeny were tested for susceptibility to WN virus infection and the ability to replicate virus to high-titers after infection. These results suggest that the trait of increased susceptibility is dominant over resistance. The enhanced ability of infected mosquitoes to replicate WN virus showed partial dominance. Both of these traits appear to be polyfactorial, and are apparently associated with more than one chromosome in Cx. tritaeniorhynchus.


Assuntos
Culex/microbiologia , Variação Genética , Vírus do Nilo Ocidental/fisiologia , Animais , Cruzamentos Genéticos , Culex/genética , Feminino , Cinética , Masculino , Mutação , Fenótipo , Seleção Genética , Especificidade da Espécie , Replicação Viral
8.
Am J Trop Med Hyg ; 40(5): 548-56, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2567124

RESUMO

Vertical transmission of Japanese encephalitis virus to the F1 adult stage was demonstrated in Culex tritaeniorhynchus, Cx. annulus, Cx. quinquefasciatus, and Armigeres subalbatus. Transmission to the F1 larval stage was demonstrated in Cx. pipiens, Aedes vexans, Ae. alcasidi, and A. flavus. In Cx. tritaeniorhynchus, vertical transmission rates (the percentage of parent females transmitting to progeny) varied (12-100%). Filial infection rates (the percentage of progeny infected) for a given mosquito virus combination were markedly affected by the interval of time between parental infection and oviposition, suggesting that vertical infection was not transovarial in nature but occurred at oviposition. Filial infection rates for Cx. tritaeniorhynchus also varied widely by family and, as measured in F1 larvae, rates in excess of 20% were observed in a family. Filial infection rates in Cx. tritaeniorhynchus F1 adults were about 4 times lower than those in larvae. Japanese encephalitis virus was sexually transmitted from male to female Cx. tritaeniorhynchus.


Assuntos
Culex/microbiologia , Culicidae/microbiologia , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Insetos Vetores/microbiologia , Animais , Culex/crescimento & desenvolvimento , Culex/fisiologia , Culicidae/crescimento & desenvolvimento , Culicidae/fisiologia , Feminino , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/fisiologia , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Oviposição , Temperatura
9.
Science ; 179(4076): 924-5, 1973 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17832772
10.
Am J Ophthalmol ; 114(4): 473-8, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1415459

RESUMO

Eighteen untreated patients with unilateral exfoliation syndrome without glaucoma were studied with regard to differences in aqueous dynamics between the affected and unaffected fellow eyes. Additionally, both eyes of the patients with exfoliation were compared to the eyes of 18 age-matched and gender-matched control subjects. Intraocular pressure was significantly higher (13.9 +/- 3.0 mm Hg [mean +/- standard deviation]) in the affected compared with the unaffected eyes (12.2 +/- 2.5 mm Hg), but no difference in aqueous humor flow was detected when eyes in the three groups were compared (affected eyes, 2.40 +/- 0.60 microliter/min; unaffected eyes, 2.40 +/- 0.65 microliter/min; control eyes, 2.61 +/- 0.60 microliter/min). Anterior chamber volumes were significantly smaller in affected (122 +/- 37 microliters) and unaffected eyes (121 +/- 37 microliters) of the patients with exfoliation compared with the eyes of the control subjects (145 +/- 30 microliters). Apparent resistance was higher in the eyes with exfoliation (6.5 +/- 1.9 min mm Hg/microliters) compared with both unaffected (5.4 +/- 1.2 min mm Hg/microliters) and control groups (5.2 +/- 1.8 min mm Hg/microliters), although these differences were not statistically significant.


Assuntos
Segmento Anterior do Olho/fisiopatologia , Humor Aquoso/fisiologia , Doenças do Cristalino/fisiopatologia , Idoso , Oftalmopatias/fisiopatologia , Feminino , Fluorofotometria , Humanos , Pressão Intraocular , Masculino , Tonometria Ocular
11.
Qual Saf Health Care ; 12(1): 24-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12571341

RESUMO

OBJECTIVES: This study measured the extent to which a systematic approach was used to select criteria for audit, and identified problems in using such an approach with potential solutions. DESIGN: A questionnaire survey using the Audit Criteria Questionnaire (ACQ), created, piloted, and validated for the purpose. Possible ACQ scores ranged from 0 to 1, indicating how systematically the criteria had been selected and how usable they were. SETTING: A stratified random sample of 10 audit leads in each of 83 randomly selected NHS trusts and all practices in each of 11 randomly selected primary care audit group areas in England and Wales. PARTICIPANTS: Audit leads of ongoing audits in each organisation in which a first data collection had started less than 12 months earlier and a second data collection was not completed. MAIN OUTCOME MEASURES: ACQ scores, problems identified in the audit criteria selection process, and solutions found. RESULTS: The mean ACQ score from all 83 NHS trusts and the 11 primary care audit groups was 0.52 (range 0.0-0.98). There was no difference between mean ACQ scores for criteria used in audits on clinical (0.51) and non-clinical (0.52) topics. The mean ACQ scores from nationally organised audits (0.59, n=33) was higher than for regional (0.51, n=21), local (0.53, n=77), or individual organisation (0.52, n=335) audits. The mean ACQ score for published audit protocols (0.56) was higher than for locally developed audits (0.49). There was no difference in ACQ scores for audits reported by general practices (0.49, n=83) or NHS trusts (0.53, n=383). Problems in criteria selection included difficulties in coordination of staff to undertake the task, lack of evidence, poor access to literature, poor access to high quality data, lack of time, and lack of motivation. Potential solutions include investment in training, protected time, improved access to literature, support staff and availability of published protocols. CONCLUSIONS: Methods of selecting review criteria were often less systematic than is desirable. Published usable audit protocols providing evidence based review criteria with information on their provenance enable appropriate review criteria to be selected, so that changes in practice based on these criteria lead to real improvement in quality rather than merely change. The availability and use of high quality audit protocols would be a valuable contribution to the evolution of clinical governance. The ACQ should be developed into a tool to help in selecting appropriate criteria to increase the effectiveness of audit.


Assuntos
Hospitais Públicos/normas , Auditoria Médica/métodos , Atenção Primária à Saúde/normas , Indicadores de Qualidade em Assistência à Saúde , Inglaterra , Pesquisa sobre Serviços de Saúde , Humanos , Medicina Estatal/normas , Inquéritos e Questionários , País de Gales
12.
Trans R Soc Trop Med Hyg ; 73(4): 445-50, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-555071

RESUMO

Genetic analysis indicates that dieldrin resistance in laboratory colonies of Anopheles culicifacies is under the control of codominant alleles of a locus in linkage group 3 (chromosome 3), approximately 31 map units from Acph (acid phosphatase).


Assuntos
Anopheles/genética , Dieldrin , Ligação Genética , Fosfatase Ácida/metabolismo , Animais , Anopheles/enzimologia , Cruzamentos Genéticos , Resistência a Medicamentos , Feminino , Masculino , Cromossomos Sexuais
13.
J Parasitol ; 83(4): 739-45, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9267419

RESUMO

A nonimmune American acquired an infection of Plasmodium vivax Type 1 malaria in Brazil in 1994. After returning to the U.S.A., he had a primary attack followed by 3 relapses. The primary attack and first 2 relapses were treated with a standard regimen of chloroquine, followed by 14 days of primaquine (15 mg/day). Following the third relapse, the primaquine treatment was extended to 28 days. No further relapses occurred. The lack of response to primaquine by this strain may recommend it as a suitable candidate for chemotherapeutic study if it can be adapted to an animal model. Anopheles quadrimaculatus mosquitoes infected by feeding on the patient during the first relapse were used to establish the strain in Aotus and Saimiri monkeys. Monkeys supported well the development of long-lasting parasitemia. Anopheles freeborni, Anopheles stephensi, and Anopheles gambiae mosquitoes were readily infected by feeding on the monkeys and by membrane feeding on diluted blood. Monkey-to-monkey transmission was obtained via the bites of infected mosquitoes and the intravenous injection of sporozoites dissected from salivary glands. This parasite is designated as the Brazil I/CDC strain of P. vivax.


Assuntos
Antimaláricos/farmacologia , Aotidae/parasitologia , Malária Vivax/parasitologia , Plasmodium vivax/efeitos dos fármacos , Primaquina/farmacologia , Saimiri/parasitologia , Animais , Anopheles , Antimaláricos/uso terapêutico , Brasil , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Modelos Animais de Doenças , Resistência a Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Insetos Vetores , Malária Vivax/tratamento farmacológico , Malária Vivax/transmissão , Masculino , Parasitemia/tratamento farmacológico , Parasitemia/patologia , Parasitemia/transmissão , Primaquina/uso terapêutico , Recidiva
14.
Qual Health Care ; 10(3): 173-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11533425

RESUMO

OBJECTIVES: To identify the desirable characteristics of review criteria for quality improvement and to determine how they should be selected. BACKGROUND: Review criteria are the elements against which quality of care is assessed in quality improvement. Use of inappropriate criteria may impair the effectiveness of quality improvement activities and resources may be wasted in activities that fail to facilitate improved care. METHODS: A two round modified Delphi process was used to generate consensus amongst an international panel of 38 experts. A list of 40 characteristics of review criteria, identified from literature searches, was distributed to the experts who were asked to rate the importance and feasibility of each characteristic. Comments and suggestions for characteristics not included in the list were also invited. RESULTS: The Delphi process refined a comprehensive literature based list of 40 desirable characteristics of review criteria into a more precise list of 26 items. The expert consensus view is that review criteria should be developed through a well documented process involving consideration of valid research evidence, possibly combined with expert opinion, prioritisation according to health outcomes and strength of evidence, and pilot testing. Review criteria should also be accompanied by full clear information on how they might be used and how data might be collected and interpreted. CONCLUSION: The desirable characteristics for review criteria have been identified and will be of use in the development, evaluation, and selection of review criteria, thus improving the cost effectiveness of quality improvement activities in healthcare settings.


Assuntos
Conferências de Consenso como Assunto , Técnica Delphi , Garantia da Qualidade dos Cuidados de Saúde/normas , Indicadores de Qualidade em Assistência à Saúde , Medicina Baseada em Evidências , Processos Grupais , Humanos
15.
Artigo em Inglês | MEDLINE | ID: mdl-614715

RESUMO

Virgin Culex tritaeniorhynchus males and females from a laboratory strain and the progeny of wild-caught females were released at a rural village on the outskirts of Lahore during late autumn to study mating behavior in nature at a time when population abundance was declining. Although both released and endemic males were numerous, few recaptured females were inseminated. Apparently during late autumn there normally is a cessation of mating activity as the population begins to enter the overwintering diapause condition even though males and virgin females may be readily collected resting in fields. These data suggested that genetic material would not be readily introduced into the overwintering population during late autumn.


Assuntos
Culex , Comportamento Sexual Animal , Animais , Temperatura Baixa , Feminino , Masculino , Paquistão , Estações do Ano , Fatores de Tempo
16.
Sci Total Environ ; 468-469: 475-86, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24051446

RESUMO

The current methods to assess the environmental impacts of plant pests differ in their approaches and there is a lack of the standardized procedures necessary to provide accurate and consistent results, demonstrating the complexity of developing a commonly accepted scheme for this purpose. By including both the structural and functional components of the environment threatened by invasive alien species (IAS), in particular plant pests, we propose an environmental risk assessment scheme that addresses this complexity. Structural components are investigated by evaluating the impacts of the plant pest on genetic, species and landscape diversity. Functional components are evaluated by estimating how plant pests modify ecosystem services in order to determine the extent to which an IAS changes the functional traits that influence ecosystem services. A scenario study at a defined spatial and temporal resolution is then used to explore how an IAS, as an exogenous driving force, may trigger modifications in the target environment. The method presented here provides a standardized approach to generate comparable and reproducible results for environmental risk assessment as a component of Pest Risk Analysis. The method enables the assessment of overall environmental risk which integrates the impacts on different components of the environment and their probabilities of occurrence. The application of the proposed scheme is illustrated by evaluating the environmental impacts of the invasive citrus long-horn beetle, Anoplophora chinensis.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Plantas/microbiologia , Plantas/parasitologia , Medição de Risco/métodos
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