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1.
J Contin Educ Nurs ; 54(4): 176-184, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37001120

RESUMO

Recent surveys of Magnet facilities and nurses found low rates of implementation of evidence-based practice in U.S. health care settings. Nursing Experts: Translating the Evidence (NExT) is a collaboration of nurses and librarians providing free online evidence-based practice nursing education benefiting nurses in all settings. The NExT online modules empowered participants to efficiently access valuable resources to inform and improve their practice in a convenient, accessible, self-paced format. Quantitative and qualitative evaluation methods and the value of collaboration are discussed. [J Contin Educ Nurs. 2023;54(4):176-184.].


Assuntos
Educação Continuada em Enfermagem , Serviços de Enfermagem Escolar , Humanos , Educação Continuada em Enfermagem/métodos , Enfermagem Baseada em Evidências/educação , Atenção à Saúde , Inquéritos e Questionários
2.
Animals (Basel) ; 12(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35158715

RESUMO

Eradication and control methods to limit damage caused to native biota in New Zealand by the stoat (Mustela erminea) rely on effective lures for trapping and detection devices, such as cameras. Long-life semiochemical lures have the potential for targeting stoats in situations where food-based lures are of limited success. The attractiveness of body odours of captive stoats was tested in a series of captive animal and extensive field trials to investigate their potential as trapping and monitoring lures. Stoats approached and spent significantly more time sniffing stoat urine and scats and bedding from oestrous female stoats than a non-treatment control. The bedding odours were attractive in both the breeding and the non-breeding season. Stoats also spent significantly more time sniffing oestrous stoat bedding than female ferret bedding, but the ferret odour also produced a significant response by stoats. In the field trials, there were no significant differences between the number of stoats caught with food lures (long-life rabbit or hen eggs) compared with oestrous female or male stoat bedding lures. These results indicate the potential of both stoat bedding odour and the scent of another mustelid species as stoat trapping lures that likely act as a general odour attractant rather than a specific chemical signal of oestrus.

3.
Public Health Nurs ; 36(1): 11-17, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30272378

RESUMO

OBJECTIVE: To explore participants' evaluation of an online sexual health intervention posted on Facebook and identify appealing and effective ways to present sexual health content to adolescents and emerging adults (AEAs). DESIGN AND MEASURES: A qualitative approach using peer moderated focus groups was used to elicit reflections on the Facebook site's content, appeal, and ease of navigation. Focus group discussions were transcribed, coded, and analyzed for themes using conventional content analysis. Demographic data were analyzed with SPSS. SAMPLE: Participants (n = 63) were recruited from a Midwestern university and both an urban and rural high school. Eight focus groups were conducted. RESULTS: Participants reported significant concerns with the stigma associated with having sexual health conversations with parents, peers or providers. Participants thought the Facebook site provided reliable sexual health information, was not condescending, and was more visually appealing than other sites frequented by technology-proficient AEA. AEAs suggested developing an independent sexual health education website. CONCLUSION: Findings demonstrate the importance for having accurate and reliable sexual health information available on the internet. The use of visually appealing social media to communicate sexual health content that is interactive, informative, and user-friendly and meets the educational needs of AEA in the Midwest is recommended.


Assuntos
Saúde do Adolescente , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde , Educação Sexual/métodos , Infecções Sexualmente Transmissíveis/prevenção & controle , Mídias Sociais , Adolescente , Adulto , Comunicação , Feminino , Humanos , Internet , Masculino , Pais , População Rural , Comportamento Sexual
4.
J Med Libr Assoc ; 105(4): 385-393, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28983202

RESUMO

OBJECTIVE: While many librarians have been asked to participate in systematic reviews with researchers, often these researchers are not familiar with the systematic review process or the appropriate role for librarians. The purpose of this study was to identify the challenges and barriers that librarians face when collaborating on systematic reviews. To take a wider view of the whole process of collaborating on systematic reviews, the authors deliberately focused on interpersonal and methodological issues other than searching itself. METHODS: To characterize the biggest challenges that librarians face while collaborating on systematic review projects, we used a web-based survey. The thirteen-item survey included seventeen challenges grouped into two categories: methodological and interpersonal. Participants were required to indicate the frequency and difficulty of the challenges listed. Open-ended questions allowed survey participants to describe challenges not listed in the survey and to describe strategies used to overcome challenges. RESULTS: Of the 17 challenges listed in the survey, 8 were reported as common by over 40% of respondents. These included methodological issues around having too broad or narrow research questions, lacking eligibility criteria, having unclear research questions, and not following established methods. The remaining challenges were interpersonal, including issues around student-led projects and the size of the research team. Of the top 8 most frequent challenges, 5 were also ranked as most difficult to handle. Open-ended responses underscored many of the challenges included in the survey and revealed several additional challenges. CONCLUSIONS: These results suggest that the most frequent and challenging issues relate to development of the research question and general communication with team members. Clear protocols for collaboration on systematic reviews, as well as a culture of mentorship, can help librarians prevent and address these challenges.


Assuntos
Bases de Dados Bibliográficas , Bibliotecários , Competência Profissional , Literatura de Revisão como Assunto , Medicina Baseada em Evidências , Humanos , Bibliotecas Médicas
5.
J Air Waste Manag Assoc ; 66(2): 173-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26284986

RESUMO

UNLABELLED: An explosive growth in natural gas production within the last decade has fueled concern over the public health impacts of air pollutant emissions from oil and gas sites in the Barnett and Eagle Ford shale regions of Texas. Commonly acknowledged sources of uncertainty are the lack of sustained monitoring of ambient concentrations of pollutants associated with gas mining, poor quantification of their emissions, and inability to correlate health symptoms with specific emission events. These uncertainties are best addressed not by conventional monitoring and modeling technology, but by increasingly available advanced techniques for real-time mobile monitoring, microscale modeling and source attribution, and real-time broadcasting of air quality and human health data over the World Wide Web. The combination of contemporary scientific and social media approaches can be used to develop a strategy to detect and quantify emission events from oil and gas facilities, alert nearby residents of these events, and collect associated human health data, all in real time or near-real time. The various technical elements of this strategy are demonstrated based on the results of past, current, and planned future monitoring studies in the Barnett and Eagle Ford shale regions. IMPLICATIONS: Resources should not be invested in expanding the conventional air quality monitoring network in the vicinity of oil and gas exploration and production sites. Rather, more contemporary monitoring and data analysis techniques should take the place of older methods to better protect the health of nearby residents and maintain the integrity of the surrounding environment.


Assuntos
Poluição do Ar/análise , Monitoramento Ambiental/métodos , Gás Natural , Indústrias Extrativas e de Processamento , Formaldeído/análise , Humanos , Modelos Teóricos , Campos de Petróleo e Gás , Projetos Piloto , Texas , Incerteza
8.
J Med Libr Assoc ; 103(3): 145-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26213507

RESUMO

QUESTION/PURPOSE: The New York University (NYU) Health Sciences Library used a new method to arrange in-depth discussions with basic science researchers. The objective was to identify collaborators for a new National Library of Medicine administrative supplement. SETTING: The research took place at the NYU Health Sciences Library. METHODS: Using the National Institutes of Health (NIH) RePORTER, forty-four researchers were identified and later contacted through individualized emails. RESULTS: Nine researchers responded to the email followed by six in-person or phone discussions. At the conclusion of this process, two researchers submitted applications for supplemental funding, and both of these applications were successful. CONCLUSIONS: This method confirmed these users could benefit from the skills and knowledge of health sciences librarians, but they are largely unaware of this.


Assuntos
Pesquisa Biomédica/organização & administração , Gestão da Informação/métodos , Armazenamento e Recuperação da Informação/métodos , Bibliotecas Médicas/organização & administração , Centros Médicos Acadêmicos , Humanos , Relações Interprofissionais
9.
Biol Psychiatry ; 77(1): 75-83, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25168609

RESUMO

BACKGROUND: Although case-control approaches are beginning to disentangle schizophrenia's complex polygenic burden, other methods will likely be necessary to fully identify and characterize risk genes. Endophenotypes, traits genetically correlated with an illness, can help characterize the impact of risk genes by providing genetically relevant traits that are more tractable than the behavioral symptoms that classify mental illness. Here, we present an analytic approach for discovering and empirically validating endophenotypes in extended pedigrees with very few affected individuals. Our approach indexes each family member's risk as a function of shared genetic kinship with an affected individual, often referred to as the coefficient of relatedness. To demonstrate the utility of this approach, we search for neurocognitive and neuroanatomic endophenotypes for schizophrenia in large unselected multigenerational pedigrees. METHODS: A fixed-effects test within the variance component framework was performed on neurocognitive and cortical surface area traits in 1606 Mexican-American individuals from large, randomly ascertained extended pedigrees who participated in the Genetics of Brain Structure and Function study. As affecteds were excluded from analyses, results were not influenced by disease state or medication usage. RESULTS: Despite having sampled just 6 individuals with schizophrenia, our sample provided 233 individuals at various levels of genetic risk for the disorder. We identified three neurocognitive measures (digit-symbol substitution, facial memory, and emotion recognition) and six medial temporal and prefrontal cortical surfaces associated with liability for schizophrenia. CONCLUSIONS: With our novel analytic approach, one can discover and rank endophenotypes for schizophrenia, or any heritable disease, in randomly ascertained pedigrees.


Assuntos
Endofenótipos , Linhagem , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Adulto , Idoso , Encéfalo/patologia , Interpretação Estatística de Dados , Família , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Americanos Mexicanos/genética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Risco , Esquizofrenia/patologia , Psicologia do Esquizofrênico
10.
Med Ref Serv Q ; 33(2): 157-66, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24735265

RESUMO

With nearly all library resources and services delivered digitally, librarians working for the New York University Health Sciences Library struggled with maintaining awareness of changing user needs, understanding barriers faced in using library resources and services, and determining knowledge management challenges across the organization. A liaison program was created to provide opportunities for librarians to meaningfully engage with users. The program was directed toward a subset of high-priority user groups to provide focused engagement with these users. Responsibility for providing routine reference service was reduced for liaison librarians to provide maximum time to engage with their assigned user communities.


Assuntos
Bibliotecários , Bibliotecas Médicas/organização & administração , Papel Profissional , Centros Médicos Acadêmicos , Humanos , Comunicação Interdisciplinar , Informática Médica , Avaliação das Necessidades , Cidade de Nova Iorque , Objetivos Organizacionais , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde
11.
Comp Med ; 64(2): 135-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24674589

RESUMO

Baboons provide a natural model of epilepsy. However, spontaneous seizures are usually sporadic, brief, and may not be observed. We hypothesized that various types of craniofacial trauma (CFT) may serve as reliable markers for epilepsy. We evaluated the type, demographics, and clinical significance of CFT in a large baboon colony. CFT was categorized according to somatotopic location, propensity to recur, and association with witnessed seizures or abnormal EEG findings. We divided the baboons with CFT into 2 groups: those with known histories of seizures (CFT+Sz, n = 176) and those without seizure histories (CFTonly; n = 515). In CFT+Sz baboons, the 568 injuries identified included periorbital (57%), scalp (27%), muzzle (12%), and facial (4%) injuries; multiple somatotopic locations or body parts were affected in 21 baboons. The most common CFT injuries associated with seizures were periorbital and scalp lesions (43% for each region). Compared with those in CFTonly animals, EEG abnormalities, including interictal epileptic discharges (IED) and photosensitivity were more prevalent in the CFT+Sz group, particularly among baboons with periorbital or scalp injuries. Compared with CFT+Sz animals, CFTonly baboons tended to have later onset and less frequent recurrence of CFT but higher prevalence of muzzle and tooth injuries. IED and photosensitivity were less prevalent in the CFTonly than the CFT+Sz group, with periorbital injuries carrying the highest and muzzle injuries the lowest association with IED or photosensitivity in both groups. Therefore, CFT in general and periorbital injuries in particular may be markers for seizures in baboons.


Assuntos
Animais de Laboratório , Epilepsia/veterinária , Traumatismos Faciais/veterinária , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/patologia , Papio , Crânio/lesões , Animais , Biomarcadores , Eletroencefalografia/veterinária , Epilepsia/complicações , Epilepsia/epidemiologia , Epilepsia/patologia , Traumatismos Faciais/etiologia , Estudos Retrospectivos , Texas/epidemiologia
13.
Epilepsy Res ; 105(1-2): 77-85, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23499213

RESUMO

This is the first large-scale epidemiological study evaluating the prevalence of interictal epileptic discharges (IEDs) and photosensitivity (PS) recorded by scalp EEG in a natural nonhuman-primate model of photosensitive, generalized epilepsy. Scalp EEG was used to characterize electroclinical phenotypes in a large baboon pedigree housed at the Southwest National Primate Research Center at the Texas Biomedical Research Institute (Texas Biomed) based upon IEDs and photosensitivity. Scalp EEG studies including intermittent light stimulation (ILS) were performed in 671 baboons. Clinical histories were available for 531 (79%) of the animals. The EEG studies lasted 53 (±11) min, during which the baboons were lightly sedated with intramuscular ketamine doses of 5.6 (±0.8) mg. The animals were further classified according to electroclinical phenotypes recorded by scalp EEG: presence or absence of IEDs, seizures and photoparoxysmal or photoconvulsive responses. Effects of age, gender, and species on EEG phenotypes were compared using (Chi-square, two-sided, α<0.05). Sensitivity and specificity of IEDs and photosensitivity to detect a history of seizures was calculated. Generalized IEDs and photosensitivity were identified in 324 (49%) and 156 (23%) pedigreed baboons, respectively. Only photosensitivity was associated with gender, significantly increased in males. Otherwise, while IEDs were marginally more prevalent among males, there were no other significant associations of IEDs or photosensitivity with age or subspecies. Photosensitivity was significantly associated with IEDs, with demonstrating a possible association with gender and subspecies. Of 531 baboons with histories of clinical events, 91 (17%) had witnessed seizures and 269 (51%) were asymptomatic. IEDs demonstrated sensitivity and specificity of 62% and 57%, and photosensitivity of 40% and 83%, for prediction of seizures, respectively. While these EEG findings mirror the high prevalence of seizures in the colony, the sensitivity and specificity of scalp EEG may have been affected by ketamine's ability to lower the threshold for IEDs and seizures, particularly in animals predisposed to epilepsy. Photosensitivity provides a specific biological marker for epilepsy in future epidemiological, genetic, behavioral and histopathological studies.


Assuntos
Eletroencefalografia/métodos , Linhagem , Fenótipo , Convulsões/genética , Convulsões/fisiopatologia , Animais , Feminino , Masculino , Papio , Convulsões/diagnóstico
14.
Adv Genet ; 81: 1-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23419715

RESUMO

Statistical genetic analysis of quantitative traits in large pedigrees is a formidable computational task due to the necessity of taking the nonindependence among relatives into account. With the growing awareness that rare sequence variants may be important in human quantitative variation, heritability and association study designs involving large pedigrees will increase in frequency due to the greater chance of observing multiple copies of rare variants among related individuals. Therefore, it is important to have statistical genetic test procedures that utilize all available information for extracting evidence regarding genetic association. Optimal testing for marker/phenotype association involves the exact calculation of the likelihood ratio statistic which requires the repeated inversion of potentially large matrices. In a whole genome sequence association context, such computation may be prohibitive. Toward this end, we have developed a rapid and efficient eigen simplification of the likelihood that makes analysis of family data commensurate with the analysis of a comparable sample of unrelated individuals. Our theoretical results which are based on a spectral representation of the likelihood yield simple exact expressions for the expected likelihood ratio test statistic (ELRT) for pedigrees of arbitrary size and complexity. For heritability, the ELRT is where h2 and λgi are, respectively, the heritability and eigenvalues of the pedigree-derived genetic relationship kernel (GRK). For association analysis of sequence variants, the ELRT is given by where ht2, hq2, and hr2 are the total, quantitative trait nucleotide, and residual heritabilities, respectively. Using these results, fast and accurate analytical power analyses are possible, eliminating the need for computer simulation. Additional benefits of eigen simplification include a simple method for calculation of the exact distribution of the ELRT under the null hypothesis which turns out to differ from that expected under the usual asymptotic theory. Further, when combined with the use of empirical GRKs-estimated over a large number of genetic markers-our theory reveals potential problems associated with nonpositive semidefinite kernels. These procedures are being added to our general statistical genetic computer package, SOLAR.


Assuntos
Modelos Genéticos , Herança Multifatorial , Linhagem , Feminino , Estudos de Associação Genética , Humanos , Funções Verossimilhança , Masculino , Fenótipo
15.
Epilepsy Res ; 101(1-2): 46-55, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22480914

RESUMO

The baboon provides a natural non-human primate model for photosensitive, generalized epilepsy. This study describes an implantation procedure for the placement of subdural grid and strip electrodes for continuous video-EEG monitoring in the epileptic baboon to evaluate the generation and propagation of ictal and interictal epileptic discharges. Subdural grid, strip and depth electrodes were implanted in six baboons, targeting brain regions that were activated in functional neuroimaging studies during photoparoxysmal responses. The baboons were monitored with continuous video-EEG monitoring for 2-21 (mean 9) days. Although the animals were tethered, the EEG signal was transmitted wirelessly to optimize their mobility. Spontaneous seizures, interictal epileptic discharges (IEDs), and responses to intermittent light stimulation (ILS) were assessed. Due to cortical injuries related to the electrode implantation and their displacement, the procedure was modified. Habitual myoclonic and generalized tonic-clonic seizures were recorded in three baboons, all associated with a generalized ictal discharge, but were triggered multiregionally, in the frontal, parietal and occipital cortices. IEDs were similarly expressed multiregionally, and responsible for triggering most generalized spike-and-wave discharges. Generalized photoparoxysmal responses were activated only in one baboon, while driving responses recorded in all three photosensitive baboons were 2.5 times the stimulus rate. In contrast to previous intracranial investigations in this model, generalized ictal and interictal epileptic discharges were triggered by parietal and occipital, in addition to the frontocentral cortices. Furthermore, targeted visual areas responded differently to ILS in photosensitive than nonphotosensitive baboons, but further studies are required before mechanisms can be implicated for ILS-induced activation of the epileptic networks.


Assuntos
Eletroencefalografia/métodos , Epilepsia Generalizada/fisiopatologia , Animais , Encéfalo/patologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Dura-Máter , Estimulação Elétrica , Eletrodos Implantados , Epilepsia Generalizada/patologia , Epilepsia Tônico-Clônica/patologia , Epilepsia Tônico-Clônica/fisiopatologia , Feminino , Inflamação/patologia , Masculino , Monitorização Fisiológica , Papio
16.
Philos Trans R Soc Lond B Biol Sci ; 367(1590): 887-94, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22312056

RESUMO

Host genetic factors exert significant influences on differential susceptibility to many infectious diseases. In addition, population structure of both host and parasite may influence disease distribution patterns. In this study, we assess the effects of population structure on infectious disease in two populations in which host genetic factors influencing susceptibility to parasitic disease have been extensively studied. The first population is the Jirel population of eastern Nepal that has been the subject of research on the determinants of differential susceptibility to soil-transmitted helminth infections. The second group is a Brazilian population residing in an area endemic for Trypanosoma cruzi infection that has been assessed for genetic influences on differential disease progression in Chagas disease. For measures of Ascaris worm burden, within-population host genetic effects are generally more important than host population structure factors in determining patterns of infectious disease. No significant influences of population structure on measures associated with progression of cardiac disease in individuals who were seropositive for T. cruzi infection were found.


Assuntos
Doença de Chagas/genética , Etnicidade/genética , Predisposição Genética para Doença/genética , Genética Populacional , Helmintíase/genética , Interações Hospedeiro-Parasita/genética , Animais , Ascaris/genética , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Helmintíase/epidemiologia , Humanos , Nepal/epidemiologia , Trypanosoma cruzi/genética
17.
Comp Med ; 62(6): 535-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23561888

RESUMO

This study evaluated the incidence, prevalence, and clinical features of seizures in a pedigreed captive colony of baboons. The association of seizures with subspecies, age, sex, and various clinical features was assessed. Records for 1527 captive, pedigreed baboons were reviewed, and 3389 events were identified in 1098 baboons. Of these events, 1537 (45%) represented witnessed seizures, whereas the remaining 1852 presented with craniofacial trauma or episodic changes in behavior that were suggestive, but not diagnostic, of seizure activity. Seizures were generalized myoclonic or tonic-clonic, with two thirds of the events witnessed in the morning. Seizure onset occurred in adolescence (age, 5 y), with an average of 3 seizures in a lifetime. The incidence and prevalence of seizures were 2.5% and 26%, respectively, whereas the prevalence of recurrent seizures (that is, epilepsy) was 15%. Seizures were more prevalent in male baboons, which tended to present with earlier onset and more seizures over a lifetime than did female baboons. Seizures were equally distributed between the subspecies; age of onset and seizure recurrences did not differ significantly between subspecies. Clinical features including age of onset, characteristics, and diurnal presentation of seizures in baboons suggested similarities to juvenile myoclonic epilepsy in humans. Facial trauma may be useful marker for epilepsy in baboons, but its specificity should be characterized.


Assuntos
Animais de Laboratório , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/patologia , Papio , Convulsões/veterinária , Fatores Etários , Animais , Feminino , Incidência , Masculino , Linhagem , Prevalência , Estudos Retrospectivos , Convulsões/epidemiologia , Convulsões/patologia , Fatores Sexuais
18.
Mech Ageing Dev ; 133(1): 11-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22155176

RESUMO

A theory of aging holds that senescence is caused by a dysregulated nuclear factor kappa B (NF-κB) signal transduction network (STN). We adopted a systems genetics approach in our study of the NF-κB STN. Ingenuity Pathways Analysis (IPA) was used to identify gene/gene product interactions between NF-κB and the genes in our transcriptional profiling array. Principal components factor analysis (PCFA) was performed on a sub-network of 19 genes, including two initiators of the toll-like receptor (TLR) pathway, myeloid differentiation primary response gene (88) (MyD88) and TIR (Toll/interleukin-1 receptor)-domain-containing adapter-inducing interferon-ß (TRIF). TLR pathways are either MyD88-dependent or TRIF-dependent. Therefore, we also performed PCFA on a subset excluding the MyD88 transcript, and on another subset excluding two TRIF transcripts. Using linkage analysis we found that each set gave rise to at least one factor with a logarithm of the odds (LOD) score greater than 3, two on chromosome 15 at 15q12 and 15q22.2, and another two on chromosome 17 at 17p13.3 and 17q25.3. We also found several suggestive signals (2

Assuntos
Envelhecimento/genética , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , NF-kappa B/genética , Locos de Características Quantitativas/fisiologia , Transdução de Sinais/genética , Cromossomos Humanos Par 15/metabolismo , Cromossomos Humanos Par 17/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Humanos , Escore Lod , Masculino , NF-kappa B/metabolismo , Polimorfismo de Nucleotídeo Único , Biologia de Sistemas/métodos
20.
Proc Biol Sci ; 277(1693): 2531-40, 2010 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-20392725

RESUMO

Malaria parasites vary in phenotypic traits of biomedical or biological interest such as growth rate, virulence, sex ratio and drug resistance, and there is considerable interest in identifying the genes that underlie this variation. An important first step is to determine trait heritability (H(2)). We evaluate two approaches to measuring H(2) in natural parasite populations using relatedness inferred from genetic marker data. We collected single-clone Plasmodium falciparum infections from 185 patients from the Thailand-Burma border, monitored parasite clearance following treatment with artemisinin combination therapy (ACT), measured resistance to six antimalarial drugs and genotyped parasites using 335 microsatellites. We found strong relatedness structure. There were 27 groups of two to eight clonally identical (CI) parasites, and 74 per cent of parasites showed significant relatedness to one or more other parasites. Initially, we used matrices of allele sharing and variance components (VC) methods to estimate H(2). Inhibitory concentrations (IC(50)) for six drugs showed significant H(2) (0.24 to 0.79, p = 0.06 to 2.85 x 10(-9)), demonstrating that this study design has adequate power. However, a phenotype of current interest--parasite clearance following ACT--showed no detectable heritability (H(2) = 0-0.09, ns) in this population. The existence of CI parasites allows the use of a simple ANOVA approach for quantifying H(2), analogous to that used in human twin studies. This gave similar results to the VC method and requires considerably less genotyping information. We conclude (i) that H(2) can be effectively measured in malaria parasite populations using minimal genotype data, allowing rational design of genome-wide association studies; and (ii) while drug response (IC(50)) shows significant H(2), parasite clearance following ACT was not heritable in the population studied.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Plasmodium falciparum/genética , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Resistência a Medicamentos , Variação Genética , Humanos , Concentração Inibidora 50 , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Fenótipo , Filogenia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/isolamento & purificação
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