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1.
Oecologia ; 196(4): 1073-1083, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338861

RESUMO

Phenology is a key driver of population and community dynamics. Phenological metrics (e.g., first date that an event occurred) often simplify information from the full phenological distribution, which may undermine efforts to determine the importance of life history events. Data regarding full phenological distributions are especially needed as many species are shifting phenology with climatic change which can alter life-history patterns and species dynamics. We tested whether skewness, kurtosis or maximum duration of breeding phenology affected juvenile emigration phenology and survival in natural populations of ringed (Ambystoma annulatum) and spotted salamanders (A. maculatum) spanning a 7-year period at two study locations. We evaluated the relative importance of different phenological metrics in breeding phenology and larval density dependence on emigration phenology and survival. We found that variability in emigration phenology differed by species, with ringed salamanders having a shorter duration and distributions that were more often right-skewed and leptokurtic compared to spotted salamanders. Emigration phenology was not linked to any measure of variability in breeding phenology, indicating phenological variability operates independently across life stages and may be subject to stage-specific influences. Emigration duration and skewness were partially explained by larval density, which demonstrates how phenological distributions may change with species interactions. Further tests that use the full phenological distribution to link variability in timing of life history events to demographic traits such as survival are needed to determine if and how phenological shifts will impact species persistence.


Assuntos
Lagoas , Urodelos , Ambystoma , Animais , Mudança Climática , Dinâmica Populacional , Estações do Ano
2.
J Community Health ; 46(2): 389-398, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33064229

RESUMO

Prostate-specific antigen (PSA) testing is one of the standard screening methods for prostate cancer (PC); however, a high proportion of men with abnormal PSA findings lack evidence for PC and may undergo unnecessary treatment. Furthermore, little is known about the prevalence of PSA testing for US men, after the US Preventive Services Task Force (USPSTF) recommended against routine PSA screening in 2012. Our objectives were to: (1) examine the self-reported patterns of PSA testing following a change in the USPSTF prostate cancer screening recommendations and (2) to determine the associated socio-demographic factors. Data were from the 2010 and 2015 National Health Interview Surveys. Men were ages ≥ 40 years and responded to the question "Ever had a PSA test?". Multivariable logistic regression was used to examine PSA testing prevalence in 2010 and 2015, and their associated socio-demographic factors. The analytic sample contained 15,372 men. A majority (75.2%) identified as non-Hispanic (NHW) and 14.2% were foreign-born. Those surveyed in 2015 were less likely to report ever having had a PSA test when compared to those in 2010. Compared to US-born and older NHW men, PSA testing was statistically significantly lower among foreign-born men and men belonging to all other racial categories. Fewer men reported PSA testing following the USPSTF 2012 recommendations. Associated socio-demographic factors included nativity, age, race/ethnicity, educational attainment and type of health insurance. Further studies are required to elucidate our findings and their health implications for the US native and foreign-born population.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Adulto , Fatores Etários , Estudos Transversais , Detecção Precoce de Câncer , Humanos , Masculino , Programas de Rastreamento , Neoplasias da Próstata/diagnóstico
3.
Mol Pharm ; 14(1): 172-182, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-28043127

RESUMO

Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Many drugs that are available for treating the disease are insufficiently effective, toxic, or too expensive. Therefore, there is a pressing need for safe, effective, and inexpensive therapeutic agents from indigenous plants used in ethnomedicines. The potential of aqueous extracts of Cajanus cajan leaf and seed, Zanthoxylum zanthoxyloides leaf, and Carica papaya leaf in sickle cell disease management was investigated in vitro using freshly prepared 2% sodium metabisulfite for sickling induction. The results indicated that the percentage of sickled cells, which was initially 91.6% in the control, was reduced to 29.3%, 41.7%, 32.8%, 38.2%, 47.6%, in the presence of hydroxyurea, C. cajan seed, C. cajan leaf, Z. zanthoxyloides leaf, and C. papaya leaf extracts, respectively, where the rate of polymerization inhibition was 6.5, 5.9, 8.0, 6.6, and 6.0 (×10-2) accordingly. It was also found that the RBC resistance to hemolysis was increased in the presence of the tested agents as indicated by the reduction of the percentage of hemolyzed cells from 100% to 0%. The phytochemical screening results indicated the presence of important phytochemicals including tannins, saponins, alkaloids, flavonoids, and glycosides in all the plant extracts. Finally, gas chromatography-mass spectrometry analysis showed the presence of important secondary metabolites in the plants. These results suggest that the plant extracts have some potential to be used as alternative antisickling therapy to hydroxyurea in SCD management.


Assuntos
Antidrepanocíticos/farmacologia , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/farmacologia , Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/química , Cajanus/química , Carica/química , Eritrócitos/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Medicina Tradicional/métodos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Saponinas/química , Saponinas/farmacologia , Sementes/química , Taninos/química , Taninos/farmacologia , Zanthoxylum/química
4.
J Biol Chem ; 290(12): 7517-34, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25631044

RESUMO

Coenzyme Q (Q or ubiquinone) is a redox active lipid composed of a fully substituted benzoquinone ring and a polyisoprenoid tail and is required for mitochondrial electron transport. In the yeast Saccharomyces cerevisiae, Q is synthesized by the products of 11 known genes, COQ1-COQ9, YAH1, and ARH1. The function of some of the Coq proteins remains unknown, and several steps in the Q biosynthetic pathway are not fully characterized. Several of the Coq proteins are associated in a macromolecular complex on the matrix face of the inner mitochondrial membrane, and this complex is required for efficient Q synthesis. Here, we further characterize this complex via immunoblotting and proteomic analysis of tandem affinity-purified tagged Coq proteins. We show that Coq8, a putative kinase required for the stability of the Q biosynthetic complex, is associated with a Coq6-containing complex. Additionally Q6 and late stage Q biosynthetic intermediates were also found to co-purify with the complex. A mitochondrial protein of unknown function, encoded by the YLR290C open reading frame, is also identified as a constituent of the complex and is shown to be required for efficient de novo Q biosynthesis. Given its effect on Q synthesis and its association with the biosynthetic complex, we propose that the open reading frame YLR290C be designated COQ11.


Assuntos
Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Ubiquinona/biossíntese , Cromatografia Líquida , Proteômica , Proteínas de Saccharomyces cerevisiae/biossíntese , Espectrometria de Massas em Tandem
5.
J Cancer Educ ; 31(4): 702-708, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-25948412

RESUMO

Community-based participatory research (CBPR) is becoming one of the dominant approaches for bringing evidence- and consensus-based cancer prevention and control practices to medically underserved communities. There are many examples of how CBPR has been useful for generating culturally specific solutions for different health issues that affect African-Americans. However, few examples exist in the literature on how the CBPR approach can be applied to address prostate cancer. This paper describes a collaborative process for linking inner-city, African-American men to free prostate cancer education, physician counseling, and screening opportunities (prostate-specific antigen (PSA) testing and digital rectal examination (DRE)). The site of this community-based participatory project was the city of Buffalo, located in Erie County, New York. The collaborative, community-academic process that is described includes the following: (1) planning and conducting a community needs assessment to contextualize local prostate cancer issues, (2) organizing town and gown event planning, and (3) manipulating aspects of the built environment to build an infrastructure within the community to address disparities in screening opportunities. This paper concludes with a description of lessons learned that can help others develop and implement similar activities in other communities.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Aconselhamento , Detecção Precoce de Câncer/estatística & dados numéricos , Avaliação das Necessidades/organização & administração , Educação de Pacientes como Assunto , Neoplasias da Próstata/diagnóstico , Negro ou Afro-Americano , Humanos , Masculino , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/prevenção & controle , Estados Unidos/epidemiologia , População Urbana
6.
Ecotoxicology ; 24(5): 1073-86, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25794558

RESUMO

Glyphosate-based herbicides are the number one pesticide in the United States and are used commonly around the world. Understanding the affects of glyphosate-based herbicides on non-target wildlife, for example amphibians, is critical for evaluation of regulations pertaining to the use of such herbicides. Additionally, it is important to understand how variation in biotic and abiotic environmental conditions, such as UV-B light regime, could potentially affect how glyphosate-based herbicides interact with non-target species. This study used artificial pond mesocosms to identify the effects of generic glyphosate-based herbicide (GLY-4 Plus) on mortality, cellular immune response, body size, and morphological plasticity of larvae of the spotted salamander (Ambystoma maculatum) under conditions that reflect moderate (UV(M)) and low (UV(L)) UV-B light regimes. Survival within a given UV-B level was unaffected by herbicide presence or absence. However, when herbicide was present, survival varied between UV-B levels with higher survival in UV(M) conditions. Herbicide presence in the UV(M) treatments also decreased body size and reduced cellular immune response. In the UV(L) treatments, the presence of herbicide increased body size and affected tail morphology. Finally, in the absence of herbicide, body size and cellular immune response were higher in UV(M) treatments compared to UV(L) treatments. Thus, the effects of herbicide on salamander fitness were dependent on UV-B level. As anthropogenic habitat modifications continue to alter landscapes that contain amphibian breeding ponds, salamanders may increasingly find themselves in locations with reduced canopy cover and increased levels of UV light. Our findings suggest that the probability of surviving exposure to the glyphosate-based herbicide used in this study may be elevated in more open canopy ponds, but the effects on other components of fitness may be varied and unexpected.


Assuntos
Ambystoma/fisiologia , Glicina/análogos & derivados , Herbicidas/toxicidade , Raios Ultravioleta , Ambystoma/imunologia , Animais , Glicina/toxicidade , Imunidade Celular/efeitos dos fármacos , Larva/efeitos dos fármacos , Glifosato
7.
J Cancer Educ ; 30(4): 623-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25288347

RESUMO

The barbershop is a promising setting where African-American men might receive information and education about prostate cancer. In this study, we assessed the feasibility of engaging rural barbershops as venues for barbers to deliver a prostate cancer education intervention to increase informed decision-making for prostate cancer screening among customers. Twelve barbershops were recruited from two separate micropolitan areas in Georgia as intervention and control sites. Structured interviews were conducted with 11 barbers in both sites about customer characteristics as well as their willingness to participate in the study. The interviews were audio recorded and transcribed for analysis. In the intervention site, six barbers completed a survey and a pre-/posttest prostate cancer knowledge instrument following training classes. Barbers reported a wide average range of customers served per week (50 to 300). African-American men made up an average of 87% of customers. Barbers thought prostate cancer was an important discussion topic, felt they would be comfortable discussing it, and supported the participation of their barbershop in the study. For intervention group barbers, there was a statistically significant difference between the average pretest knowledge score of 72% (mean 12.2, SD=3.2) and the posttest knowledge score of 89% (mean 15.2, SD=1.1) (P=0.03) on the 17-item prostate cancer knowledge instrument. Based on the multiple interactions with the barbers, there was high receptivity to the topic and consensus about the importance of addressing prostate cancer with their customers. Rural barbershops represent feasible venues for delivering a prostate cancer education intervention.


Assuntos
Barbearia , Negro ou Afro-Americano/estatística & dados numéricos , Educação em Saúde/métodos , Promoção da Saúde/métodos , Neoplasias da Próstata/etnologia , Adulto , Idoso , Comportamento do Consumidor , Estudos de Viabilidade , Feminino , Seguimentos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , População Rural
8.
Biochim Biophys Acta ; 1831(4): 776-791, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23270816

RESUMO

Coenzyme Qn (ubiquinone or Qn) is a redox active lipid composed of a fully substituted benzoquinone ring and a polyisoprenoid tail of n isoprene units. Saccharomyces cerevisiae coq1-coq9 mutants have defects in Q biosynthesis, lack Q6, are respiratory defective, and sensitive to stress imposed by polyunsaturated fatty acids. The hallmark phenotype of the Q-less yeast coq mutants is that respiration in isolated mitochondria can be rescued by the addition of Q2, a soluble Q analog. Yeast coq10 mutants share each of these phenotypes, with the surprising exception that they continue to produce Q6. Structure determination of the Caulobacter crescentus Coq10 homolog (CC1736) revealed a steroidogenic acute regulatory protein-related lipid transfer (START) domain, a hydrophobic tunnel known to bind specific lipids in other START domain family members. Here we show that purified CC1736 binds Q2, Q3, Q10, or demethoxy-Q3 in an equimolar ratio, but fails to bind 3-farnesyl-4-hydroxybenzoic acid, a farnesylated analog of an early Q-intermediate. Over-expression of C. crescentus CC1736 or COQ8 restores respiratory electron transport and antioxidant function of Q6 in the yeast coq10 null mutant. Studies with stable isotope ring precursors of Q reveal that early Q-biosynthetic intermediates accumulate in the coq10 mutant and de novo Q-biosynthesis is less efficient than in the wild-type yeast or rescued coq10 mutant. The results suggest that the Coq10 polypeptide:Q (protein:ligand) complex may serve essential functions in facilitating de novo Q biosynthesis and in delivering newly synthesized Q to one or more complexes of the respiratory electron transport chain.


Assuntos
Antioxidantes/metabolismo , Transporte de Elétrons/fisiologia , Peptídeos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Ubiquinona/metabolismo , Sequência de Aminoácidos , Transporte de Elétrons/genética , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Ubiquinona/análogos & derivados
9.
Conserv Biol ; 27(1): 95-102, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23140535

RESUMO

Biological invasions and habitat alteration are often detrimental to native species, but their interactions are difficult to predict. Interbreeding between native and introduced species generates novel genotypes and phenotypes, and human land use alters habitat structure and chemistry. Both invasions and habitat alteration create new biological challenges and opportunities. In the intensively farmed Salinas Valley, California (U.S.A.), threatened California tiger salamanders (Ambystoma californiense) have been replaced by hybrids between California tiger salamander and introduced barred tiger salamanders (Ambystoma tigrinum mavortium). We conducted an enclosure experiment to examine the effects habitat modification and relative frequency of hybrid and native California tiger salamanders have on recruitment of salamanders and their prey, Pacific chorus frogs (Pseudacris regilla). We tested whether recruitment differed among genetic classes of tiger salamanders (hybrid or native) and pond hydroperiod (seasonal or perennial). Roughly 6 weeks into the experiment, 70% (of 378 total) of salamander larvae died in 4 out of 6 ponds. Native salamanders survived (n = 12) in these ponds only if they had metamorphosed prior to the die-offs. During die-offs, all larvae of native salamanders died, whereas 56% of hybrid larvae died. We necropsied native and hybrid salamanders, tested water quality, and queried the California Department of Pesticide Regulation database to investigate possible causes of the die-offs. Salamander die-offs, changes in the abundance of other community members (invertebrates, algae, and cyanobacteria), shifts in salamander sex ratio, and patterns of pesticide application in adjacent fields suggest that pesticide use may have contributed to die-offs. That all survivors were hybrids suggests that environmental stress may promote rapid displacement of native genotypes.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Urodelos/fisiologia , Qualidade da Água , Animais , California , Vigor Híbrido , Hibridização Genética , Larva/fisiologia , Modelos Logísticos , Praguicidas/análise , Dinâmica Populacional , Ranidae/fisiologia , Urodelos/genética , Urodelos/crescimento & desenvolvimento , Água/química
10.
Proc Natl Acad Sci U S A ; 107(8): 3606-10, 2010 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20133596

RESUMO

When introduced or cultivated plants or animals hybridize with their native relatives, the spread of invasive genes into native populations might have biological, aesthetic, and legal implications. Models suggest that the rate of displacement of native by invasive alleles can be rapid and inevitable if they are favored by natural selection. We document the spread of a few introduced genes 90 km into a threatened native species (the California Tiger Salamander) in 60 years. Meanwhile, a majority of genetic markers (65 of 68) show little evidence of spread beyond the region where introductions occurred. Using computer simulations, we found that such a pattern is unlikely to emerge by chance among selectively neutral markers. Therefore, our results imply that natural selection has favored both the movement and fixation of these exceptional invasive alleles. The legal status of introgressed populations (native populations that are slightly genetically modified) is unresolved by the US Endangered Species Act. Our results illustrate that genetic and ecological factors need to be carefully weighed when considering different criteria for protection, because different rules could result in dramatically different geographic areas and numbers of individuals being protected.


Assuntos
Quimera/genética , Espécies em Perigo de Extinção , Extinção Biológica , Deriva Genética , Seleção Genética , Alelos , Animais , California , Evolução Molecular , Marcadores Genéticos , Variação Genética
11.
Circ Cardiovasc Qual Outcomes ; 16(4): e009697, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37017086

RESUMO

BACKGROUND: Epidemiologic studies have documented the associations between experiences of discrimination and adverse health outcomes. However, the relationship between discrimination and mortality, and the factors that may moderate this relationship are not well understood. This study examined whether lifetime and everyday discrimination were associated with all-cause and cardiovascular mortality and whether these associations differed by race and ethnicity, gender, and racial and ethnic residential segregation. METHODS: The study included 1633 Black, 1403 Hispanic/Latino, and 2473 White participants aged 45 to 84 years from the Multi-Ethnic Study of Atherosclerosis, enrolled from 2000 to 2002 and followed across 5 exams (2002-2018). Discrimination was measured using the lifetime discrimination (major experiences of unfair treatment) and everyday discrimination (day-to-day experiences of unfair treatment) scales. Racial and ethnic residential segregation was measured using the Gi* statistic. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% CIs, adjusting for sociodemographic characteristics, health behaviors, and clinical risk factors. RESULTS: Each increase in reports of lifetime discrimination was associated with increased all-cause (HR, 1.06 [95% CI, 1.00-1.11]) and cardiovascular (HR, 1.15 [95% CI, 1.04-1.27]) mortality, adjusting for sociodemographic factors, health behaviors, and clinical risk factors. Associations between lifetime discrimination and cardiovascular mortality were observed across all racial and ethnic groups but were strongest and only statistically significant among Black participants (HR, 1.18 [95% CI, 1.02-1.37]). Additionally, in the fully adjusted model, each increase in reports of everyday discrimination was strongly associated with increased cardiovascular mortality (HR, 1.21 [95% CI, 1.03-1.43]). Associations for lifetime and everyday discrimination with all-cause and cardiovascular mortality were not modified by race and ethnicity, gender, or racial and ethnic residential segregation. CONCLUSIONS: These findings suggest that experiences of discrimination are associated with increased all-cause and cardiovascular mortality.


Assuntos
Doenças Cardiovasculares , Discriminação Social , Humanos , Aterosclerose/diagnóstico , Etnicidade , Hispânico ou Latino , Modelos de Riscos Proporcionais , Brancos , Negro ou Afro-Americano , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/mortalidade , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
12.
Proc Natl Acad Sci U S A ; 106(27): 11166-71, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19564601

RESUMO

Although the ecological consequences of species invasions are well studied, the ecological impacts of genetic introgression through hybridization are less understood. This is particularly true of the impacts of hybridization on "third party" community members not genetically involved in hybridization. We also know little about how direct interactions between hybrid and parental individuals influence fitness. Here, we examined the ecological effects of hybridization between the native, threatened California Tiger Salamander (Ambystoma californiense) and the introduced Barred Tiger Salamander (Ambystoma tigrinum mavortium). Native x introduced hybrids are widespread in California, where they are top predators in seasonal ponds. We examined the impacts of early generation hybrids (first 2 generations of parental crosses) and contemporary hybrids derived from ponds where hybrids have been under selection in the wild for 20 generations. We found that most classes of hybrid tiger salamander larvae dramatically reduced survival of 2 native community members, the Pacific Chorus Frog (Pseudacris regilla) and the California Newt (Taricha torosa). We also found that native A. californiense larvae were negatively impacted by the presence of hybrid larvae: Native survival and size at metamorphosis were reduced and time to metamorphosis was extended. We also observed a large influence of Mendelian dominance on size, metamorphic timing and predation rate of hybrid tiger salamanders. These results suggest that both genetic and ecological factors are likely to influence the dynamics of admixture, and that tiger salamander hybridization might constitute a threat to additional pond-breeding species of concern in the region.


Assuntos
Ambystoma/genética , Anfíbios/crescimento & desenvolvimento , Hibridização Genética , Comportamento Predatório , Ambystoma/anatomia & histologia , Animais , Tamanho Corporal , California , Cruzamentos Genéticos , Feminino , Genótipo , Masculino , Metamorfose Biológica , Fenótipo , Dinâmica Populacional , Especificidade da Espécie
13.
South Med J ; 105(6): 294-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22665151

RESUMO

OBJECTIVES: A major challenge facing contemporary cancer educators is how to optimize the dissemination of breast cancer prevention and control information to African American women in the Deep South who are believed to be cancer free. The purpose of this research was to provide insight into the breast cancer information-acquisition experiences of African American women in Alabama and Mississippi and to make recommendations on ways to better reach members of this high-risk, underserved population. METHODS: Focus group methodology was used in a repeated, cross-sectional research design with 64 African American women, 35 years old or older who lived in one of four urban or rural counties in Alabama and Mississippi. RESULTS: Axial-coded themes emerged around sources of cancer information, patterns of information acquisition, characteristics of preferred sources, and characteristics of least-preferred sources. CONCLUSIONS: It is important to invest in lay health educators to optimize the dissemination of breast cancer information to African American women who are believed to be cancer free in the Deep South.


Assuntos
Negro ou Afro-Americano , Neoplasias da Mama/etnologia , Educação em Saúde/métodos , Adulto , Idoso , Alabama , Neoplasias da Mama/prevenção & controle , Estudos Transversais , Feminino , Grupos Focais , Humanos , Pessoa de Meia-Idade , Mississippi , Risco
14.
Genetica ; 139(2): 209-19, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21161568

RESUMO

We investigated genetic diversity of the hellbender (Cryptobranchus alleganiensis) throughout its range in the eastern US using nuclear markers and compared our results to a previously published mitochondrial analysis. A variety of nuclear markers, including protein-coding gene introns and microsatellites were tested but only microsatellites were variable enough for population level analysis. Microsatellite loci showed moderate among population sharing of alleles, in contrast to the reciprocal monophyly exhibited by mitochondrial DNA. However, analyses using F-statistics and Bayesian clustering algorithms showed considerable population subdivision and clustered hellbender populations into the same major groups as the mtDNA. The microsatellites combined with the mtDNA data suggest that gene flow is severely restricted or non-existent among eight major groups, and potentially among populations (rivers) within groups. The combined mtDNA and microsatellite data suggest that the currently recognized hellbender subspecies are paraphyletic. We suggest that the eight independent groups identified in our study should be managed as such, rather than basing conservation decisions on the two named subspecies of hellbender.


Assuntos
DNA Mitocondrial/genética , Genética Populacional , Repetições de Microssatélites/genética , Urodelos/genética , Alelos , Animais , Núcleo Celular/genética , Análise por Conglomerados , Conservação dos Recursos Naturais , Fluxo Gênico , Variação Genética , Geografia , Filogeografia , Rios , Estados Unidos
15.
J Cancer Educ ; 26(4): 708-16, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21626265

RESUMO

The purposes of this study are to explore cancer information acquisition patterns among African-American men and to evaluate relationships between information acquisition patterns and prostate cancer prevention and control knowledge. A random sample of 268 men participated in a statewide interviewer-administered, telephone survey. Men classified as non-seekers, non-medical source seekers, and medical source seekers of prostate cancer information differed on household income, level of education, and beliefs about personal risk for developing prostate cancer. Results from multiple regression analysis indicated that age, education, and information-seeking status were associated with overall levels of prostate cancer knowledge. Results from logistic regression analyses indicated that men who included physicians as one of many information resources (medical source seekers) had superior knowledge over non-seekers and non-medical source seekers on 33% of individual knowledge details. The findings emphasize the need to connect lower-income and lower-educated African-American men to physicians as a source of prostate cancer control information.


Assuntos
Negro ou Afro-Americano/educação , Negro ou Afro-Americano/psicologia , Informação de Saúde ao Consumidor , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto , Neoplasias da Próstata/prevenção & controle , Neoplasias da Próstata/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etnologia , Fatores de Risco , Inquéritos e Questionários
16.
BMC Evol Biol ; 10: 147, 2010 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-20482794

RESUMO

BACKGROUND: Introductions of non-native tiger salamanders into the range of California tiger salamanders have provided a rare opportunity to study the early stages of secondary contact and hybridization. We produced first- and second-generation hybrid salamanders in the lab and measured viability among these early-generation hybrid crosses to determine the strength of the initial barrier to gene exchange. We also created contemporary-generation hybrids in the lab and evaluated the extent to which selection has affected fitness over approximately 20 generations of admixture. Additionally, we examined the inheritance of quantitative phenotypic variation to better understand how evolution has progressed since secondary contact. RESULTS: We found significant variation in the fitness of hybrids, with non-native backcrosses experiencing the highest survival and F2 hybrids the lowest. Contemporary-generation hybrids had similar survival to that of F2 families, contrary to our expectation that 20 generations of selection in the wild would eliminate unfit genotypes and increase survival. Hybrid survival clearly exhibited effects of epistasis, whereas size and growth showed mostly additive genetic variance, and time to metamorphosis showed substantial dominance. CONCLUSIONS: Based on first- and second- generation cross types, our results suggest that the initial barrier to gene flow between these two species was relatively weak, and subsequent evolution has been generally slow. The persistence of low-viability recombinant hybrid genotypes in some contemporary populations illustrates that while hybridization can provide a potent source of genetic variation upon which natural selection can act, the sorting of fit from unfit gene combinations might be inefficient in highly admixed populations. Spatio-temporal fluctuation in selection or complex genetics has perhaps stalled adaptive evolution in this system despite selection for admixed genotypes within generations.


Assuntos
Ambystoma/genética , Aptidão Genética , Genética Populacional , Hibridização Genética , Animais , Cruzamentos Genéticos , Evolução Molecular , Fluxo Gênico , Variação Genética , Genótipo , Modelos Estatísticos , Fenótipo , Característica Quantitativa Herdável , Análise de Regressão , Análise de Sequência de DNA
17.
Mol Ecol ; 19(11): 2184-95, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20465588

RESUMO

Molecular markers have become a fundamental piece of modern biology's toolkit. In the last decade, new genomic resources from model organisms and advances in DNA sequencing technology have altered the way that these tools are developed, alleviating the marker limitation that researchers previously faced and opening new areas of research for studies of non-model organisms. This availability of markers is directly responsible for advances in several areas of research, including fine-scaled estimation of population structure and demography, the inference of species phylogenies, and the examination of detailed selective pressures in non-model organisms. This review summarizes methods for the development of large numbers of DNA markers in non-model organisms, the challenges encountered when utilizing different methods, and new research applications resulting from these advances.


Assuntos
Marcadores Genéticos , Genômica/métodos , Evolução Biológica , Mapeamento Cromossômico , Ecologia , Genética Populacional , Geografia , Filogenia , Análise de Sequência de DNA/métodos
18.
BMC Evol Biol ; 9: 176, 2009 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-19630983

RESUMO

BACKGROUND: Hybrid zones represent valuable opportunities to observe evolution in systems that are unusually dynamic and where the potential for the origin of novelty and rapid adaptation co-occur with the potential for dysfunction. Recently initiated hybrid zones are particularly exciting evolutionary experiments because ongoing natural selection on novel genetic combinations can be studied in ecological time. Moreover, when hybrid zones involve native and introduced species, complex genetic patterns present important challenges for conservation policy. To assess variation of admixture dynamics, we scored a large panel of markers in five wild hybrid populations formed when Barred Tiger Salamanders were introduced into the range of California Tiger Salamanders. RESULTS: At three of 64 markers, introduced alleles have largely displaced native alleles within the hybrid populations. Another marker (GNAT1) showed consistent heterozygote deficits in the wild, and this marker was associated with embryonic mortality in laboratory F2's. Other deviations from equilibrium expectations were idiosyncratic among breeding ponds, consistent with highly stochastic demographic effects. CONCLUSION: While most markers retain native and introduced alleles in expected proportions, strong selection appears to be eliminating native alleles at a smaller set of loci. Such rapid fixation of alleles is detectable only in recently formed hybrid zones, though it might be representative of dynamics that frequently occur in nature. These results underscore the variable and mosaic nature of hybrid genomes and illustrate the potency of recombination and selection in promoting variable, and often unpredictable genetic outcomes. Introgression of a few, strongly selected introduced alleles should not necessarily affect the conservation status of California Tiger Salamanders, but suggests that genetically pure populations of this endangered species will be difficult to maintain.


Assuntos
Ambystoma/genética , Quimera/genética , Genética Populacional , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Alelos , Animais , California , Conservação dos Recursos Naturais , Evolução Molecular , Frequência do Gene , Marcadores Genéticos , Hibridização Genética , Análise de Sequência de DNA
19.
Am J Pharm Educ ; 83(4): 7222, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31223167

RESUMO

Global engagement between schools and colleges of pharmacy in the United States and Africa is increasing. For a balanced and fruitful engagement, sensitivity towards the cultural and clinical needs of the people and professionals of the African region is critical. In this paper, we have divided the discussion into Southern, East, Central, and West Africa. General information about Africa, with unique aspects for individual subregions and countries, will be introduced. Stereotypes and misconceptions about the region and the people will also be discussed, along with recommendations for culturally sensitive engagement for pharmacy and other health care practitioners when hosting members from, or visiting this region. The paper is a resource for schools and colleges of pharmacy who are currently engaged or considering future outreach opportunities in Africa.


Assuntos
Competência Cultural , Educação em Farmácia/organização & administração , Cooperação Internacional , Faculdades de Farmácia/organização & administração , África , Pessoal de Saúde/organização & administração , Humanos , Estados Unidos
20.
Pan Afr Med J ; 34: 214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32180886

RESUMO

INTRODUCTION: Substance abuse is an important public health issue affecting West Africa; however, there is currently a dearth of literature on the actions needed to address it. The aim of this study was to assess the risks and protective factors of substance abuse in Ghana, West Africa, using the photovoice method. METHODS: This study recruited and trained 10 participants in recovery from substance abuse and undergoing treatment in the greater Accra region of Ghana on the photovoice methodology. Each participant received a disposable camera to take pictures that represented the risk and protective factors pertinent to substance abuse in their communities. They were also given the opportunity to provide narratives of the pictures using pre-identified themes and the different levels of the social-ecological model and participatory action research (PAR). RESULTS: Participants identified at the individual level: ignorance; interpersonal level: family and peer pressure; organizational level: lack of regulation; community level: media, availability of drugs, cost of drugs, urbanization, slum communities and cultural factors; and policy level: lack of regulations and their enforcement. Education and beliefs were cited at the individual level; family at the interpersonal level; religion at the organizational level; organizing youth, media and narcotics anonymous at the community level; and nothing at the policy level. CONCLUSION: This is an exploratory study that will add to the limited body of knowledge in the scientific literature with respect to substance abuse in the country and also help develop interventions to address the respective needs of several communities in Ghana.


Assuntos
Fotografação , Saúde Pública , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Pesquisa Participativa Baseada na Comunidade , Feminino , Gana/epidemiologia , Humanos , Masculino , Fatores de Proteção , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/reabilitação
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