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1.
Mol Cancer Res ; 20(4): 501-514, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980595

RESUMO

Growth factor independence-1 (GFI1) is a transcriptional repressor and master regulator of normal and malignant hematopoiesis. Repression by GFI1 is attributable to recruitment of LSD1-containing protein complexes via its SNAG domain. However, the full complement of GFI1 partners in transcriptional control is not known. We show that in T-acute lymphoblastic leukemia (ALL) cells, GFI1 and IKAROS are transcriptional partners that co-occupy regulatory regions of hallmark T-cell development genes. Transcriptional profiling reveals a subset of genes directly transactivated through the GFI1-IKAROS partnership. Among these is NOTCH3, a key factor in T-ALL pathogenesis. Surprisingly, NOTCH3 expression by GFI1 and IKAROS requires the GFI1 SNAG domain but occurs independent of SNAG-LSD1 binding. GFI1 variants deficient in LSD1 binding fail to activate NOTCH3, but conversely, small molecules that disrupt the SNAG-LSD1 interaction while leaving the SNAG primary structure intact stimulate NOTCH3 expression. These results identify a noncanonical transcriptional control mechanism in T-ALL which supports GFI1-mediated transactivation in partnership with IKAROS and suggest competition between LSD1-containing repressive complexes and others favoring transactivation. IMPLICATIONS: Combinatorial diversity and cooperation between DNA binding proteins and complexes assembled by them can direct context-dependent transcriptional outputs to control cell fate and may offer new insights for therapeutic targeting in cancer.


Assuntos
Proteínas de Ligação a DNA , Regulação Leucêmica da Expressão Gênica , Fator de Transcrição Ikaros , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Fatores de Transcrição , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Fator de Transcrição Ikaros/genética , Fator de Transcrição Ikaros/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Mol Cell Biol ; 39(13)2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30988160

RESUMO

Growth factor independence 1B (GFI1B) coordinates assembly of transcriptional repressor complexes comprised of corepressors and histone-modifying enzymes to control gene expression programs governing lineage allocation in hematopoiesis. Enforced expression of GFI1B in K562 erythroleukemia cells favors erythroid over megakaryocytic differentiation, providing a platform to define molecular determinants of binary fate decisions triggered by GFI1B. We deployed proteome-wide proximity labeling to identify factors whose inclusion in GFI1B complexes depends upon GFI1B's obligate effector, lysine-specific demethylase 1 (LSD1). We show that GFI1B preferentially recruits core and putative elements of the BRAF-histone deacetylase (HDAC) (BHC) chromatin-remodeling complex (LSD1, RCOR1, HMG20A, HMG20B, HDAC1, HDAC2, PHF21A, GSE1, ZMYM2, and ZNF217) in an LSD1-dependent manner to control acquisition of erythroid traits by K562 cells. Among these elements, depletion of both HMG20A and HMG20B or of GSE1 blocks GFI1B-mediated erythroid differentiation, phenocopying impaired differentiation brought on by LSD1 depletion or disruption of GFI1B-LSD1 binding. These findings demonstrate the central role of the GFI1B-LSD1 interaction as a determinant of BHC complex recruitment to enable cell fate decisions driven by GFI1B.


Assuntos
Células Eritroides/citologia , Histona Desmetilases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Animais , Células COS , Diferenciação Celular , Chlorocebus aethiops , Regulação para Baixo , Células Eritroides/metabolismo , Histona Desacetilases/metabolismo , Humanos , Células K562 , Fenótipo , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica
3.
J Am Assoc Nurse Pract ; 30(9): 511-518, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30113532

RESUMO

BACKGROUND AND PURPOSE: This study determined the impact of an interprofessional education (IPE) simulation on family nurse practitioner (FNP) students' and family medicine residents' (FMRs) self-reported confidence in counseling women reluctant to engage in cancer screening or evaluation and assessed knowledge of breast and cervical cancer risk factors. METHOD: A multi-item knowledge survey on breast and cervical cancer risk factors was administered to 76 FNP students and FMRs followed by an IPE simulation with a pre-/postsurvey of self-reported confidence in counseling a woman reluctant to have breast and cervical cancer screening and evaluation. DISCUSSION: Data demonstrated knowledge deficits in breast and cervical cancer risk factors in both disciplines with the average risk factor knowledge score of 8.5/12 for breast cancer and 7.8/12 for cervical cancer. Following IPE simulation, confidence in counseling women reluctant to have breast or cervical cancer screening improved across both disciplines (p < .05) and debrief feedback findings suggest improved attitudes toward collegiality, communication, and understanding of other interprofessional roles among both disciplines. CONCLUSION: Knowledge gaps exist among both FNP students and FMRs in breast and cervical cancer risk factors. This study suggests IPE simulation is effective in building individual provider confidence and team collegiality.


Assuntos
Neoplasias da Mama/diagnóstico , Competência Clínica/normas , Educação Continuada/normas , Programas de Rastreamento/métodos , Neoplasias do Colo do Útero/diagnóstico , Atitude do Pessoal de Saúde , Neoplasias da Mama/terapia , Distribuição de Qui-Quadrado , Currículo/normas , Currículo/tendências , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Educação Continuada/métodos , Feminino , Humanos , Comunicação Interdisciplinar , Programas de Rastreamento/normas , Inquéritos e Questionários , Texas , Neoplasias do Colo do Útero/terapia
5.
J Community Health ; 42(4): 770-778, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28155005

RESUMO

A steady decline in cervical cancer incidence and mortality in the United States has been attributed to increased uptake of cervical cancer screening tests such as Papanicolau (Pap) tests. However, disparities in Pap test compliance exist, and may be due in part to perceived barriers or lack of knowledge about risk factors for cervical cancer. This study aimed to assess correlates of cervical cancer risk factor knowledge and examine socio-demographic predictors of self-reported barriers to screening among a group of low-income uninsured women. Survey and procedure data from 433 women, who received grant-funded cervical cancer screenings over a span of 33 months, were examined for this project. Data included demographics, knowledge of risk factors, and agreement on potential barriers to screening. Descriptive analysis showed significant correlation between educational attainment and knowledge of risk factors (r = 0.1381, P < 0.01). Multivariate analyses revealed that compared to Whites, Hispanics had increased odds of identifying fear of finding cancer (OR 1.56, 95% CI 1.00-2.43), language barriers (OR 4.72, 95% CI 2.62-8.50), and male physicians (OR 2.16, 95% CI 1.32-3.55) as barriers. Hispanics (OR 1.99, 95% CI 1.16-3.44) and Blacks (OR 2.06, 95% CI 1.15-3.68) had a two-fold increase in odds of agreeing that lack of knowledge was a barrier. Identified barriers varied with age, marital status and previous screening. Programs aimed at conducting free or subsidized screenings for medically underserved women should include culturally relevant education and patient care in order to reduce barriers and improve screening compliance for safety-net populations.


Assuntos
Detecção Precoce de Câncer/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Pessoas sem Cobertura de Seguro de Saúde/etnologia , Neoplasias do Colo do Útero/etnologia , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Adulto , Medo , Feminino , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Grupos Raciais , Fatores de Risco , Fatores Socioeconômicos , Estados Unidos , Adulto Jovem
6.
Prev Med Rep ; 5: 257-262, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28133601

RESUMO

Two human papillomavirus (HPV) vaccines are available and can prevent 98% of HPV 16 and 18 infections. This study aimed to explore determinants of 1) HPV vaccine awareness among a cohort of low-income women participating in a cancer prevention program in Central Texas and compare them to United States residents; 2) determinants of healthcare providers' discussion of HPV vaccine among female residents of the United States. Bivariate and multivariable analysis of HPV vaccine awareness using survey data (n = 359) collected between 2014 and 2016 in Central Texas, and the Health Information and Nutrition Survey (HINTS) data which is a nationally representative dataset (unweighted n = 1214) collected in 2013 were conducted. Bivariate and multivariable regression analyses of healthcare providers' discussion of the HPV vaccine using the HINTS survey data were also conducted. Compared to non-Hispanic Whites, there was a decreased likelihood of HPV vaccine awareness among non-Hispanic Blacks (OR = 0.50; 95% CI = 0.28-0.90) and Hispanics (OR = 0.55; 95% CI = 0.30-0.99) in the grant funded program, as well as non-Hispanic Blacks (OR = 0.28; 95% CI = 0.14-0.58) and Hispanics (OR = 0.22; 95% CI = 0.12-0.41) in the HINTS data. There was also a decreased likelihood of healthcare providers discussing the HPV vaccine with respondents who were 35-49 years (OR = 0.50; 95% CI = 0.30-0.84), 50-64 years (OR = 0.26; 95% CI = 0.14-0.49) or ≥ 65 years compared to those who were 18-34 years among the HINTS data respondents. Interventions to increase HPV awareness among non-Hispanic Blacks and Hispanics, as well as encourage healthcare providers' discussion of the HPV vaccination during patient encounters regardless of the patient's age are needed.

7.
Biochem J ; 473(19): 3355-69, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27480105

RESUMO

Proper hematopoietic cell fate decisions require co-ordinated functions of transcription factors, their associated co-regulators, and histone-modifying enzymes. Growth factor independence 1 (GFI1) is a zinc finger transcriptional repressor and master regulator of normal and malignant hematopoiesis. While several GFI1-interacting proteins have been described, how GFI1 leverages these relationships to carry out transcriptional repression remains unclear. Here, we describe a functional axis involving GFI1, SMYD2, and LSD1 that is a critical contributor to GFI1-mediated transcriptional repression. SMYD2 methylates lysine-8 (K8) within a -(8)KSKK(11)- motif embedded in the GFI1 SNAG domain. Methylation-defective GFI1 SNAG domain lacks repressor function due to failure of LSD1 recruitment and persistence of promoter H3K4 di-methyl marks. Methylation-defective GFI1 also fails to complement GFI1 depletion phenotypes in developing zebrafish and lacks pro-growth and survival functions in lymphoid leukemia cells. Our data show a discrete methylation event in the GFI1 SNAG domain that facilitates recruitment of LSD1 to enable transcriptional repression and co-ordinate control of hematopoietic cell fate in both normal and malignant settings.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Histona Desmetilases/metabolismo , Fatores de Transcrição/fisiologia , Transcrição Gênica/fisiologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Linhagem da Célula , Metilação de DNA , Proteínas de Ligação a DNA/química , Humanos , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/química , Peixe-Zebra
8.
Mol Cell Biol ; 36(10): 1438-50, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26951200

RESUMO

Cell fate specification requires precise coordination of transcription factors and their regulators to achieve fidelity and flexibility in lineage allocation. The transcriptional repressor growth factor independence 1 (GFI1) is comprised of conserved Snail/Slug/Gfi1 (SNAG) and zinc finger motifs separated by a linker region poorly conserved with GFI1B, its closest homolog. Moreover, GFI1 and GFI1B coordinate distinct developmental fates in hematopoiesis, suggesting that their functional differences may derive from structures within their linkers. We show a binding interface between the GFI1 linker and the SP-RING domain of PIAS3, an E3-SUMO (small ubiquitin-related modifier) ligase. The PIAS3 binding region in GFI1 contains a conserved type I SUMOylation consensus element, centered on lysine-239 (K239). In silico prediction algorithms identify K239 as the only high-probability site for SUMO modification. We show that GFI1 is modified by SUMO at K239. SUMOylation-resistant derivatives of GFI1 fail to complement Gfi1 depletion phenotypes in zebrafish primitive erythropoiesis and granulocytic differentiation in cultured human cells. LSD1/CoREST recruitment and MYC repression by GFI1 are profoundly impaired for SUMOylation-resistant GFI1 derivatives, while enforced expression of MYC blocks granulocytic differentiation. These findings suggest that SUMOylation within the GFI1 linker favors LSD1/CoREST recruitment and MYC repression to govern hematopoietic differentiation.


Assuntos
Hematopoese , Histona Desmetilases/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas Inibidoras de STAT Ativados/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Animais , Sítios de Ligação , Células COS , Diferenciação Celular , Chlorocebus aethiops , Regulação da Expressão Gênica , Células HEK293 , Células HL-60 , Humanos , Lisina/metabolismo , Camundongos , Chaperonas Moleculares/química , Células NIH 3T3 , Ligação Proteica , Proteínas Inibidoras de STAT Ativados/química , Proteínas Proto-Oncogênicas/química , Proteínas Repressoras/química , Sumoilação
9.
Prev Med ; 85: 98-105, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872393

RESUMO

BACKGROUND: Demand for a wide array of colorectal cancer screening strategies continues to outpace supply. One strategy to reduce this deficit is to dramatically increase the number of primary care physicians who are trained and supportive of performing office-based colonoscopies or flexible sigmoidoscopies. This study evaluates the clinical and economic implications of training primary care physicians via family medicine residency programs to offer colorectal cancer screening services as an in-office procedure. METHODS: Using previously established clinical and economic assumptions from existing literature and budget data from a local grant (2013), incremental cost-effectiveness ratios are calculated that incorporate the costs of a proposed national training program and subsequent improvements in patient compliance. Sensitivity analyses are also conducted. RESULTS: Baseline assumptions suggest that the intervention would produce 2394 newly trained residents who could perform 71,820 additional colonoscopies or 119,700 additional flexible sigmoidoscopies after ten years. Despite high costs associated with the national training program, incremental cost-effectiveness ratios remain well below standard willingness-to-pay thresholds under base case assumptions. Interestingly, the status quo hierarchy of preferred screening strategies is disrupted by the proposed intervention. CONCLUSIONS: A national overhaul of family medicine residency programs offering training for colorectal cancer screening yields satisfactory incremental cost-effectiveness ratios. However, the model places high expectations on primary care physicians to improve current compliance levels in the US.


Assuntos
Neoplasias Colorretais/economia , Detecção Precoce de Câncer/economia , Internato e Residência/economia , Médicos de Atenção Primária/educação , Colonoscopia/economia , Colonoscopia/educação , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Análise Custo-Benefício , Detecção Precoce de Câncer/métodos , Humanos , Internato e Residência/métodos , Internato e Residência/tendências , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Modelos Econométricos , Médicos de Atenção Primária/economia , Sigmoidoscopia/economia , Sigmoidoscopia/educação , Sigmoidoscopia/métodos , Estados Unidos
10.
J Am Board Fam Med ; 28(6): 713-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26546646

RESUMO

BACKGROUND: An inadequate supply of physicians who perform colonoscopies contributes to suboptimal screening rates, especially among the underserved. This shortage could be reduced if primary care physicians perform colonoscopies. This purpose of this article is to report quality indicators from colonoscopy procedures performed by family medicine physicians as part of a colorectal cancer prevention program targeting uninsured, low-income individuals. METHODS: A grant-funded colorectal cancer screening program was implemented to increase access to affordable colonoscopies for underinsured or uninsured residents of target counties while providing colonoscopy training to family medicine resident physicians. Colonoscopies were performed or supervised by 4 board-certified family physicians. Data were collected between 2011 and 2014. RESULTS: A total of 1155 colonoscopies were performed on 1101 individuals over a 3-year period. Cecal intubation rate was 96.25%. Adenoma detection rates among men and women >50 years old were 38.15% and 25.96%, respectively. There was 1 perforation, which was referred to a hospital, and 1 instance of postprocedural bleeding, which spontaneously resolved. CONCLUSIONS: Primary care physicians performing colonoscopies met the recommended quality indicators set forth by the American Society for Gastrointestinal Endoscopy.


Assuntos
Colonoscopia/normas , Programas de Rastreamento/normas , Atenção Primária à Saúde , Adenocarcinoma/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benchmarking , Neoplasias do Colo/diagnóstico , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde , Pessoa de Meia-Idade , Indicadores de Qualidade em Assistência à Saúde , Adulto Jovem
11.
Prev Med Rep ; 2: 158-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26844065

RESUMO

OBJECTIVE: To determine the association between health literacy, communication habits and colorectal cancer (CRC) screening among low-income patients. METHODS: Survey responses of patients who received financial assistance for colonoscopy between 2011 and 2014 at a family medicine residency clinic were analyzed using multivariate logistic regression (n = 456). There were two dependent variables: (1) previous CRC screening and (2) CRC screening adherence. Our independent variables of interest were health literacy and communication habits. RESULTS: Over two-thirds (67.13%) of respondents had not been previously screened for CRC. Multivariate analysis showed a decreased likelihood of previous CRC screening among those who had marginal (OR = 0.52; 95% CI = 0.29-0.92) or inadequate health literacy (OR = 0.49; 95% CI = 0.27-0.87) compared to those with adequate health literacy. Controlling for health literacy, the significant association between educational attainment and previous CRC screening was eliminated. Thus, health literacy mediated the relationship between educational attainment and previous CRC screening. There was no significant association between communication habits and previous CRC screening. There was no significant association between screening guideline adherence, and health literacy or communication. CONCLUSION: Limited health literacy is a potential barrier to CRC screening. Suboptimal CRC screening rates reported among those with lower educational attainment may be mediated by limited health literacy.

12.
J Community Health ; 40(2): 260-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25096763

RESUMO

Colorectal cancer (CRC) is the third most common type of cancer among both males and females in the United States and the second leading cause of cancer-related deaths. Although largely preventable through screening, early detection and removal of polyps, screening rates are considered sub-optimal. Perceived barriers to screening have been reported to influence screening rates. This paper examines variations in the extent to which uninsured patients identified barriers to CRC screening using colonoscopy based on race/ethnicity, educational attainment, age, gender, marital status and prior colonoscopy. Multivariate analyses showed that compared to Caucasians, African Americans had an increased likelihood of identifying lack of transportation as a barrier [odds ratio (OR) 2.68; 95 % confidence interval (CI) 1.35-5.32] while Hispanics were more likely to identify fear of finding cancer as a barrier (OR 2.09; 95 % CI 1.19-3.66). Compared to those with more than a high school education, there was increased likelihood of identifying lack of knowledge as a barrier among individuals with high school education (OR 3.51; 95 % CI 1.94-6.36) or less than a high school education (OR 2.16; 95 % CI 1.04-4.50). Our findings suggest that strategies aimed at increasing colonoscopy screening rates among underserved populations should take into consideration race/ethnicity, educational attainment, age, and prior colonoscopy experience when developing education and outreach plans to reduce barriers to colonoscopy.


Assuntos
Colonoscopia/estatística & dados numéricos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/etnologia , Detecção Precoce de Câncer/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Negro ou Afro-Americano , Fatores Etários , Idoso , Colonoscopia/economia , Detecção Precoce de Câncer/economia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hispânico ou Latino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Fatores Sexuais , Fatores Socioeconômicos , Estados Unidos , População Branca
13.
BMC Bioinformatics ; 14 Suppl 13: S6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24267049

RESUMO

BACKGROUND: Molecular evolution is a very active field of research, with several complementary approaches, including dN/dS, HON90, MM01, and others. Each has documented strengths and weaknesses, and no one approach provides a clear picture of how natural selection works at the molecular level. The purpose of this work is to present a simple new method that uses quantitative amino acid properties to identify and characterize directional selection in proteins. METHODS: Inferred amino acid replacements are viewed through the prism of a single physicochemical property to determine the amount and direction of change caused by each replacement. This allows the calculation of the probability that the mean change in the single property associated with the amino acid replacements is equal to zero (H0: µ = 0; i.e., no net change) using a simple two-tailed t-test. RESULTS: Example data from calanoid and cyclopoid copepod cytochrome oxidase subunit I sequence pairs are presented to demonstrate how directional selection may be linked to major shifts in adaptive zones, and that convergent evolution at the whole organism level may be the result of convergent protein adaptations. CONCLUSIONS: Rather than replace previous methods, this new method further complements existing methods to provide a holistic glimpse of how natural selection shapes protein structure and function over evolutionary time.


Assuntos
Evolução Molecular , Seleção Genética , Alinhamento de Sequência/métodos , Análise de Sequência de Proteína , Intervalos de Confiança , Especiação Genética , Genoma Mitocondrial , Humanos
14.
Tex Med ; 108(2): e1, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22714802

RESUMO

This study was conducted to determine if a parent-oriented educational intervention reduces the use of emergency department (ED) services for the care of infants. Infants aged 7 days to 1 year and older children aged 2 to 10 years were tracked for 3 years in two separate primary care (PC) practices in Washington County, Texas, with the last year being the interventional study period. Also, infants aged 7 days to 1 year and older children aged 7 days to 5 years were tracked in a third PC practice in Burleson County, Texas. The study group consisted of all parents of patients aged 7 days to 1 year seen by the pediatric group in Washington County during the 1-year interventional period. Only parents of infants in the study group received a specific educational intervention booklet. Five separate control groups were followed in this study. The control groups received usual care with standardized patient information, but they did not receive the educational intervention booklet. Each group was evaluated by calculating its monthly ED utilization rate, which is the quotient derived from dividing the number of children from that particular group seen in the ED per month by the number of children from the same group seen in the PC clinic per month. A difference of proportions test was applied to test for statistical significance regarding ED utilization. Compared with parents in the control group, parents receiving the intervention booklet (the study group) showed significantly (P < .05) lower use of ED services for care of their infants. We found no change in ED utilization for children of parents receiving other standard educational information.


Assuntos
Serviço Hospitalar de Emergência , Pais , Humanos , Atenção Primária à Saúde , Texas
15.
Int J Bioinform Res Appl ; 8(1-2): 67-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22450271

RESUMO

Amino acid property methods have repeatedly proven more sensitive than nucleotide-based methods, especially to the subtle influences of selection on Single Nucleotide Polymorphisms (SNPs). The purpose of this study is to evaluate the effects of population sampling and sliding window size on the sensitivity of one amino acid based method by assessing drug resistant SNPs from the HIV-1 gag-pol gene. The analysis of most of the SNPs produced positive results. There was not a trend in terms of properties affected most often, but sliding window size affected results more than population sampling.


Assuntos
Aminoácidos/genética , Proteínas de Fusão gag-pol/genética , Polimorfismo de Nucleotídeo Único , Farmacorresistência Viral/genética , HIV-1/genética , HIV-1/metabolismo
16.
Am Fam Physician ; 83(5): 547-52, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21391521

RESUMO

Dyspepsia affects up to 40 percent of adults each year and is often diagnosed as functional (nonulcer) dyspepsia. The defining symptoms are postprandial fullness, early satiation, or epigastric pain or burning in the absence of causative structural disease. These symptoms may coexist with symptoms of functional gastrointestinal disorders, such as gastroesophageal reflux and irritable bowel syndrome, as well as anxiety and depression. The history and physical examination can help identify other possible causes of the symptoms. Warning signs of serious disease, such as cancer, are unintended weight loss, progressive dysphagia, persistent vomiting, evidence of gastrointestinal bleeding, and a family history of cancer. In these cases, more extensive laboratory investigation, imaging, and endoscopy should be considered as clinically indicated. During the initial evaluation, a test-and-treat strategy to identify and eradicate Helicobacter pylori infection is more effective than empiric treatment and more cost-effective than initial endoscopy. Eradication of H. pylori helps one out of 15 patients with functional dyspepsia diagnosed by endoscopy, but may not be cost-effective. Treatment options that may be beneficial for functional dyspepsia include histamine H2 blockers, proton pump inhibitors, and prokinetic agents. Although psychotropic medications and psychological interventions have no proven benefit in patients with functional dyspepsia, they are appropriate for treating common psychiatric comorbidities.


Assuntos
Dispepsia/diagnóstico , Antidepressivos/uso terapêutico , Diagnóstico Diferencial , Dispepsia/tratamento farmacológico , Dispepsia/fisiopatologia , Dispepsia/psicologia , Dispepsia/terapia , Ácido Gástrico/metabolismo , Motilidade Gastrointestinal/efeitos dos fármacos , Humanos
17.
Fam Med ; 43(2): 106-11, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21305425

RESUMO

BACKGROUND AND OBJECTIVES: A substantial proportion of emergency department (ED) visits by children are for non-urgent care. The objective of this research is to determine whether a parent-focused educational intervention can reduce non-urgent ED visits. METHODS: A regional hospital system (which includes a central hospital, four satellite hospitals, and two primary care clinics) provided monthly data retrospectively from January 2006 to October 2007 on ED visits by children. The same information was provided prospectively from November 2007 to April 2009. Starting in November 2007, a family medicine residency program affiliated with the same hospital network distributed a 6.7 grade reading level booklet on non-urgent care of children to the parents who brought their children to the outpatient clinic. The number of ED visits as a proportion of outpatient clinic visits at the residency program was calculated for each month and compared to historical and geographic trends. RESULTS: Long-term changes were observed only among the intervention group. There was a substantial and statistically significant reduction in ED use for non-urgent care of children. There was also a proportional reduction in ED charges for this group. CONCLUSION: An educational intervention among parents can substantially reduce non-urgent ED visits for their children.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Medicina de Família e Comunidade/estatística & dados numéricos , Internato e Residência/estatística & dados numéricos , Relações Pais-Filho , Educação de Pacientes como Assunto/métodos , Criança , Proteção da Criança , Avaliação Educacional/métodos , Escolaridade , Humanos , Modelos Educacionais , Pacientes Ambulatoriais/estatística & dados numéricos , Educação de Pacientes como Assunto/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Análise de Regressão , Estudos Retrospectivos , Texas , Fatores de Tempo
18.
Int J Bioinform Res Appl ; 6(2): 120-33, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20223735

RESUMO

TreeSAAP has been used in a variety of protein studies for detecting adaptation in terms of the physicochemical properties involved in amino acid replacement. The accuracy of TreeSAAP was here tested using simulated protein-coding DNA data. A sampling of 1402 simulated amino acid replacements resulted in a default accuracy of 81.1%, with most properties exhibiting >90% accuracy. More than half of the false-positive results were traced to just 11 of the 180 possible single-step amino acid exchanges. Overall accuracy increased as the number of magnitude partitions used in the analysis decreased. Sliding window size did not significantly affect accuracy.


Assuntos
Biologia Computacional/métodos , Proteínas/química , Software , Bases de Dados de Proteínas , Evolução Molecular , Proteínas/genética , Análise de Sequência de Proteína
19.
PLoS One ; 4(6): e5836, 2009 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-19503808

RESUMO

BACKGROUND: Metabolism of energy nutrients by the mitochondrial electron transport chain (ETC) is implicated in the aging process. Polymorphisms in core ETC proteins may have an effect on longevity. Here we investigate the cytochrome b (cytb) polymorphism at amino acid 7 (cytbI7T) that distinguishes human mitochondrial haplogroup H from haplogroup U. PRINCIPAL FINDINGS: We compared longevity of individuals in these two haplogroups during historical extremes of caloric intake. Haplogroup H exhibits significantly increased longevity during historical caloric restriction compared to haplogroup U (p = 0.02) while during caloric abundance they are not different. The historical effects of natural selection on the cytb protein were estimated with the software TreeSAAP using a phylogenetic reconstruction for 107 mammal taxa from all major mammalian lineages using 13 complete protein-coding mitochondrial gene sequences. With this framework, we compared the biochemical shifts produced by cytbI7T with historical evolutionary pressure on and near this polymorphic site throughout mammalian evolution to characterize the role cytbI7T had on the ETC during times of restricted caloric intake. SIGNIFICANCE: Our results suggest the relationship between caloric restriction and increased longevity in human mitochondrial haplogroup H is determined by cytbI7T which likely enhances the ability of water to replenish the Q(i) binding site and decreases the time ubisemiquinone is at the Q(o) site, resulting in a decrease in the average production rate of radical oxygen species (ROS).


Assuntos
Envelhecimento , Restrição Calórica , Citocromos b/metabolismo , DNA Mitocondrial/genética , Longevidade/genética , Mitocôndrias/metabolismo , Polimorfismo Genético , Sítios de Ligação , Evolução Molecular , Feminino , Radicais Livres , Humanos , Modelos Genéticos , Conformação Molecular , Filogenia
20.
Curr Biol ; 19(7): 590-5, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19303296

RESUMO

Profound ecological changes are occurring on coral reefs throughout the tropics, with marked coral cover losses and concomitant algal increases, particularly in the Caribbean region. Historical declines in the abundance of large Caribbean reef fishes likely reflect centuries of overexploitation. However, effects of drastic recent degradation of reef habitats on reef fish assemblages have yet to be established. By using meta-analysis, we analyzed time series of reef fish density obtained from 48 studies that include 318 reefs across the Caribbean and span the time period 1955-2007. Our analyses show that overall reef fish density has been declining significantly for more than a decade, at rates that are consistent across all subregions of the Caribbean basin (2.7% to 6.0% loss per year) and in three of six trophic groups. Changes in fish density over the past half-century are modest relative to concurrent changes in benthic cover on Caribbean reefs. However, the recent significant decline in overall fish abundance and its consistency across several trophic groups and among both fished and nonfished species indicate that Caribbean fishes have begun to respond negatively to habitat degradation.


Assuntos
Antozoários , Ecossistema , Peixes , Densidade Demográfica , Animais , Região do Caribe , Conservação dos Recursos Naturais , Ecologia
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