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1.
J Behav Med ; 47(3): 355-373, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38017250

RESUMO

Studies show that interpersonal relations impact behavior change. Yet, a comprehensive review of their efficacy remains unclear. This systematic review examines the efficacy of dyadic and group-based studies that intervened on primary endpoints: diet, PA, and weight loss in adults and their networks. We searched five databases for eligible articles published from 1980 to present. Final inclusion and risk of bias were independently determined and agreed upon by two of the paper's co-authors. Nine dyads and twelve group-based studies were eligible. Of the studies, 36% (4/11) of PA studies, 60% (3/5) of diet studies and 57% (8/14) of studies with weight loss as primary outcomes, reported significant findings. Compared to dyadic interventions, a greater proportion of group-based interventions demonstrated efficacy in PA gain and weight loss as outcomes. Approximately 43% of studies demonstrated low to moderate methodological quality. This systematic review synthesized the evidence of dyadic and group studies that intervened on PA, diet, and weight in adults from the same network. Moderately-high risk of bias and lack of diverse representation restricts inferences around efficacy. High-quality rigorous research is needed to understand the efficacy of dyadic and group-based interventions in addressing these co-occurring endpoints of interest.


Assuntos
Dieta , Redução de Peso , Adulto , Humanos , Exercício Físico , Relações Interpessoais
2.
Sports Biomech ; : 1-15, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35586943

RESUMO

Hip extensor muscles are critical to sport performance as events requiring sprinting and forceful landings are highly dependent on these muscles. Despite biomechanical differences between the barbell hip thrust (BHT) and the barbell glute bridge (BGB), both are biomechanically efficient ways to load this musculature for training purposes. Research investigating the differences in muscular activity between the BHT and BGB has yet been conducted. The aim of this study was to investigate, through surface electromyography, if one exercise is more optimal than the other in producing greater muscle activation for specific hip extensor muscles. Ten male participants completed a two-part study protocol. Results revealed the BHT elicited significantly greater muscle activity within the vastus lateralis for peak and mean outcomes; however, the BGB elicited significantly greater muscle activity in the upper and lower gluteus maximus for peak and mean outcomes and mean outcome in the gluteus medius. Current findings suggest, the BGB is, at minimum, a superior substitute for the BHT for eliciting a larger magnitude of activity in the gluteus maximus. Future studies between the two exercises are warranted to discern which produces greater hypertrophy and whether adaption of the BHT or BGB transfers more optimally to sport performance.

3.
J Immigr Minor Health ; 23(5): 1011-1020, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33043411

RESUMO

African American and Hispanic women report less physical activity (PA) than non-Hispanic White women. As such, a digitally-enhanced 16-week social support pilot intervention was conducted to promote PA among African American and Hispanic women dyads. This study quantitatively and qualitatively examined the engagement and satisfaction of participants (N = 30; 15 dyads) assigned to the intervention. Intervention participants received telephone counseling calls based on motivational interviewing and a Jawbone UP activity monitor. Intervention engagement and satisfaction data were collected from the Jawbone UP, call logs, self-report questionnaires conducted at the 16-week follow-up, and two post-intervention focus groups. Nonparametric tests assessed group differences across engagement and satisfaction measures, and a manually-driven coding scheme was used to evaluate emerging themes from qualitative text. Participants demonstrated high engagement in the telephone counseling sessions and moderate engagement with the Jawbone UP. Friend/co-worker dyads and participants who were 45 years and older were more likely to use the device. Qualitative results emphasized participants' appreciation for the counseling calls, the Jawbone UP, and the overall dyadic framework of the study to collectively nurture social support and accountability for PA. Overall, the intervention group reacted positively to study components. Additional research is needed to understand the role of technology in facilitating long-lasting PA change via social support in minority populations.


Assuntos
Negro ou Afro-Americano , Satisfação Pessoal , Exercício Físico , Feminino , Humanos , Projetos Piloto , Apoio Social
4.
Artigo em Inglês | MEDLINE | ID: mdl-31517177

RESUMO

BACKGROUND: Next-generation sequencing (NGS) for tumor molecular profiling can reveal secondary germline pathogenic and likely pathogenic variants (LPV/PV). The American College of Medical Genetics (ACMG) recommends return of secondary results for a subset of 59 genes, but other genes with evidence of clinical utility are emerging. We previously reported that 4.3% of patients who underwent NGS of a targeted panel of 201 genes had LPV/PV based on the ACMG list. Here we report the frequency of additional germline cancer-related gene variants and discuss their clinical utility. PATIENTS AND METHODS: Matched tumor and germline DNA NGS of a targeted panel of 201 genes was performed in a research laboratory on samples from 1000 patients with advanced or metastatic solid tumors enrolled in a molecular testing protocol (NCT01772771). The frequency of germline LPV/PV in 54 cancer-related genes, beyond the genes in ACMG list, were analyzed. RESULTS: Among 1000 patients who underwent tumor/normal DNA sequencing, 46 (4.6%) were found to have a germline LPV/PV in the following genes: AR-(5), ATM-(4), BAP1-(1), CDH1-(1), CDKN2A-(1), CHEK1-(2), CHEK2-(10), EGFR-(1), ERCC3-(4), ERCC5-(1), HNF1B-(1), HRAS-(1), MITF-(4), MLL3-(1), NF1-(3), PKHD1-(4), PTCH1-(1), and SMARCA4-(1). Thus, a total 8.7% of patients had an LPV/PV with 2 patients having 2 concomitant germline LPV/PV. Five mutations in high-penetrance hereditary cancer predisposition genes were selected to be returned to patients or their representatives: BAP1, CDH1, CDKN2A, EGFR, and SMARCA4. CONCLUSIONS: Broader genomic testing is likely to identify additional secondary pathogenic germline alterations, some with potential clinical utility for return to patients and their relatives. The recommended genes for which germline results should be returned are continually changing, warranting continued study.

5.
Ann Oncol ; 27(5): 795-800, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26787237

RESUMO

BACKGROUND: Next-generation sequencing in cancer research may reveal germline variants of clinical significance. We report patient preferences for return of results and the prevalence of incidental pathogenic germline variants (PGVs). PATIENTS AND METHODS: Targeted exome sequencing of 202 genes was carried out in 1000 advanced cancers using tumor and normal DNA in a research laboratory. Pathogenic variants in 18 genes, recommended for return by The American College of Medical Genetics and Genomics, as well as PALB2, were considered actionable. Patient preferences of return of incidental germline results were collected. Return of results was initiated with genetic counseling and repeat CLIA testing. RESULTS: Of the 1000 patients who underwent sequencing, 43 had likely PGVs: APC (1), BRCA1 (11), BRCA2 (10), TP53 (10), MSH2 (1), MSH6 (4), PALB2 (2), PTEN (2), TSC2 (1), and RB1 (1). Twenty (47%) of 43 variants were previously known based on clinical genetic testing. Of the 1167 patients who consented for a germline testing protocol, 1157 (99%) desired to be informed of incidental results. Twenty-three previously unrecognized mutations identified in the research environment were confirmed with an orthogonal CLIA platform. All patients approached decided to proceed with formal genetic counseling; in all cases where formal genetic testing was carried out, the germline variant of concern validated with clinical genetic testing. CONCLUSIONS: In this series, 2.3% patients had previously unrecognized pathogenic germline mutations in 19 cancer-related genes. Thus, genomic sequencing must be accompanied by a plan for return of germline results, in partnership with genetic counseling.


Assuntos
Mutação em Linhagem Germinativa/genética , Proteínas de Neoplasias/genética , Neoplasias/genética , Exoma/genética , Aconselhamento Genético , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias/diagnóstico , Neoplasias/patologia
6.
Nat Commun ; 5: 3856, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24920014

RESUMO

Recent genome-wide association studies (GWAS) of Hodgkin lymphoma (HL) have identified associations with genetic variation at both HLA and non-HLA loci; however, much of heritable HL susceptibility remains unexplained. Here we perform a meta-analysis of three HL GWAS totaling 1,816 cases and 7,877 controls followed by replication in an independent set of 1,281 cases and 3,218 controls to find novel risk loci. We identify a novel variant at 19p13.3 associated with HL (rs1860661; odds ratio (OR)=0.81, 95% confidence interval (95% CI) = 0.76-0.86, P(combined) = 3.5 × 10(-10)), located in intron 2 of TCF3 (also known as E2A), a regulator of B- and T-cell lineage commitment known to be involved in HL pathogenesis. This meta-analysis also notes associations between previously published loci at 2p16, 5q31, 6p31, 8q24 and 10p14 and HL subtypes. We conclude that our data suggest a link between the 19p13.3 locus, including TCF3, and HL risk.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Cromossomos Humanos Par 19/genética , Predisposição Genética para Doença , Doença de Hodgkin/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Mol Genet Genomics ; 274(2): 141-54, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16049682

RESUMO

To identify the molecular changes that occur in non-small cell lung carcinoma (NSCLC), we compared the gene expression profile of the NCI-H292 (H292) NSCLC cell line with that of normal human tracheobronchial epithelial (NHTBE) cells. The NHTBE cells were grown in a three-dimensional organotypic culture system that permits maintenance of the normal pseudostratified mucociliary phenotype characteristic of bronchial epithelium in vivo. Microarray analysis using the Affymetrix oligonucleotide chip U95Av2 revealed that 1,683 genes showed a >1.5-fold change in expression in the H292 cell line relative to the NHTBE cells. Specifically, 418 genes were downregulated and 1,265 were upregulated in the H292 cells. The expression data for selected genes were validated in several different NSCLC cell lines using quantitative real-time PCR and Western analysis. Further analysis of the differentially expressed genes indicated that WNT responses, apoptosis, cell cycle regulation and cell proliferation were significantly altered in the H292 cells. Functional analysis using fluorescence-activated cell sorting confirmed concurrent changes in the activity of these pathways in the H292 line. These findings show that (1) NSCLC cells display deregulation of the WNT, apoptosis, proliferation and cell cycle pathways, as has been found in many other types of cancer cells, and (2) that organotypically cultured NHTBE cells can be used as a reference to identify genes and pathways that are differentially expressed in tumor cells derived from bronchogenic epithelium.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Apoptose , Sequência de Bases , Brônquios/citologia , Brônquios/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , DNA Complementar/genética , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Traqueia/citologia , Traqueia/metabolismo
9.
J Subst Abuse ; 13(3): 337-46, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11693456

RESUMO

PURPOSE: To examine heroin use and associated morbidity in young adults undergoing drug detoxification. METHODS: A retrospective chart review of all persons (ages 18-25) admitted to either of the two state-funded detoxification facilities in Rhode Island was conducted between June 1998 and June 1999. Only those reporting heroin as a primary drug were included in this study (N=201). RESULTS: Clients were largely male (64%), and white (79%), with a mean age of 22. Of those that reported heroin as their primary drug, 62% used primarily by injection. Mean age of initiation for heroin use was 18.3 years. Twenty-two percent reported a psychiatric diagnosis, and 80% reported a substance-abusing family member. Injection, previous overdose, and a mother with a history of substance use were associated with early initiation of heroin use. CONCLUSIONS: The majority of young adults with heroin addiction undergoing detoxification began using heroin during late adolescence. Concurrence of psychiatric and medical diagnoses with heroin addiction was common, and may contribute to the severity of drug use. Efforts to identify risk factors for heroin and other injection drug use in adolescents and young adults will be critical for the design of effective interventions to prevent injection drug use and its associated morbidities.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Aditivo/psicologia , Dependência de Heroína/psicologia , Adolescente , Adulto , Comportamento Aditivo/epidemiologia , Saúde da Família , Feminino , Dependência de Heroína/epidemiologia , Humanos , Masculino , Transtornos Mentais/psicologia , Estudos Retrospectivos , Rhode Island/epidemiologia , Centros de Tratamento de Abuso de Substâncias
10.
Bioorg Med Chem ; 9(9): 2387-93, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11553480

RESUMO

Bacterial chemotactic responses are initiated when certain small molecules (i.e., carbohydrates, amino acids) interact with bacterial chemoreceptors. Although bacterial chemotaxis has been the subject of intense investigations, few have explored the influence of attractant structure on signal generation and chemotaxis. Previously, we found that polymers bearing multiple copies of galactose interact with the chemoreceptor Trg via the periplasmic binding protein glucose/galactose binding protein (GGBP). These synthetic multivalent ligands were potent agonists of Escherichia coli chemotaxis. Here, we report on the development of a second generation of multivalent attractants that possess increased chemotactic activities. Strikingly, the new ligands can alter bacterial behavior at concentrations 10-fold lower than those required with the original displays; thus, they are some of the most potent synthetic chemoattractants known. The potency depends on the number of galactose moieties attached to the oligomer backbone and the length of the linker tethering these carbohydrates. Our investigations reveal the plasticity of GGBP; it can bind and mediate responses to several carbohydrates and carbohydrate derivatives. These attributes of GGBP may underlie the ability of bacteria to sense a variety of ligands with relatively few receptors. Our results provide insight into the design and development of compounds that can modulate bacterial chemotaxis and pathogenicity.


Assuntos
Proteínas de Ligação ao Cálcio , Fatores Quimiotáticos/síntese química , Fatores Quimiotáticos/farmacologia , Escherichia coli/fisiologia , Proteínas Periplásmicas de Ligação , Fatores Quimiotáticos/química , Quimiotaxia/efeitos dos fármacos , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Galactose/química , Galactose/metabolismo , Galactose/farmacologia , Microscopia de Vídeo , Modelos Moleculares , Proteínas de Transporte de Monossacarídeos/metabolismo , Relação Estrutura-Atividade
11.
Am J Drug Alcohol Abuse ; 27(3): 491-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11506264

RESUMO

We examined patients' attitudes toward HIV testing in the setting of acute substance abuse treatment and determined the prevalence of offering routine on-site testing for human immunodeficiency virus (HIV) in inpatient state-funded detoxification centers in New England. Voluntary questionnaires were administered to patients (N = 66 respondents) at the only two state-funded inpatient drug detoxification treatment centers in Rhode Island, and a telephone survey of all state-funded inpatient detoxification facilities across the New England area was conducted. In New England, 17/38 (44.7%) of all state-funded inpatient detoxification facilities didnot routinely offer on-site HIV testing to clients. Of participants, 97% responded positively to the question, "Do you think HIV testing should be available to patients in drug detoxification facilities such as this one?" There were 89% who reported that they would cope "about the same" or "better" with receiving a positive HIV test result while in detoxification treatment versus elsewhere. The greatest number of participants ranked the Orasure HIV test, an assay for HIV-1 transmucosal antibody, as the test they would most prefer while in drug treatment. However, 59% of patients responded that the type of test offered would not make a difference in whether they chose testing. Most patients indicated that they would want to see a physician within a few days of a positive diagnosis of HIV infection. Despite the controversy surrounding the provision of HIV testing to patients in inpatient acute substance abuse treatment, HIV testing is desired among these patients provided that HIV clinical care is readily available.


Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/sangue , Infecções por HIV/psicologia , Centros de Tratamento de Abuso de Substâncias , Doença Aguda , Adulto , Feminino , Grupos Focais , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Rhode Island , Transtornos Relacionados ao Uso de Substâncias/psicologia , Inquéritos e Questionários
12.
Curr Opin Chem Biol ; 4(6): 696-703, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11102876

RESUMO

Processes such as cell-cell recognition and the initiation of signal transduction often depend on the formation of multiple receptor-ligand complexes at the cell surface. Synthetic multivalent ligands are unique probes of these complex cell-surface-binding events. Multivalent ligands can be used as inhibitors of receptor-ligand interactions or as activators of signal transduction pathways. Emerging from these complementary applications is insight into how cells exploit multivalent interactions to bind with increased avidity and specificity and how cell-surface receptor organization influences signaling and the cellular responses that result.


Assuntos
Ligantes , Receptores de Superfície Celular/efeitos dos fármacos , Animais , Humanos , Receptores de Superfície Celular/agonistas , Receptores de Superfície Celular/antagonistas & inibidores
13.
Chem Biol ; 7(8): 583-91, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11048949

RESUMO

BACKGROUND: Multivalent ligands have been used previously to investigate the role of ligand valency and receptor clustering in eliciting biological responses. Studies of multivalent ligand function, however, typically have employed divalent ligands or ligands of undefined valency. How cells respond to multivalent ligands of distinct valencies, which can cluster a signaling receptor to different extents, has never been examined. The chemoreceptors, which mediate chemotactic responses in bacteria, are localized, and clustering has been proposed to play a role in their function. Using multivalent ligands directed at the chemoreceptors, we hypothesized that we could exploit ligand valency to control receptor occupation and clustering and, ultimately, the cellular response. RESULTS: To investigate the effects of ligand valency on the bacterial chemotactic response, we generated a series of linear multivalent arrays with distinct valencies by ring-opening metathesis polymerization. We report that these synthetic ligands elicit bacterial chemotaxis in both Escherichia coli and Bacillus subtilis. The chemotactic response depended on the valency of the ligand; the response of the bacteria can be altered by varying chemoattractant ligand valency. Significantly, these differences in chemotactic responses were related to the ability of the multivalent ligands to cluster chemoreceptors at the plasma membrane. CONCLUSIONS: Our results demonstrate that ligand valency can be used to tune the chemotactic responses of bacteria. This mode of regulation may arise from changes in receptor occupation or changes in receptor clustering or both. Our data implicate changes in receptor clustering as one important mechanism for altering cellular responses. Given the diverse events modulated by changes in the spatial proximity of cell surface receptors, our results suggest a general strategy for tuning biological responses.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Fatores Quimiotáticos/síntese química , Fatores Quimiotáticos/farmacologia , Quimiotaxia/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Bacillus subtilis/citologia , Bacillus subtilis/metabolismo , Biopolímeros/química , Biopolímeros/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Fatores Quimiotáticos/química , Escherichia coli/citologia , Escherichia coli/metabolismo , Corantes Fluorescentes , Galactose/análogos & derivados , Galactose/farmacologia , Glucose/análogos & derivados , Glucose/farmacologia , Ligantes , Locomoção/efeitos dos fármacos , Microscopia de Fluorescência , Microscopia de Vídeo , Estrutura Molecular , Agregação de Receptores/efeitos dos fármacos
14.
AIDS Read ; 10(7): 421-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10932846

RESUMO

In the United States today, half of all new HIV infections are injection drug use-associated, many of which are a result of the reuse and sharing of contaminated syringes. Thus, providing access to sterile syringes for injection drug users is an important part of preventing HIV transmission. Needle exchange programs (NEPs) have been established as one successful approach to providing sterile injection equipment. The medical literature shows that these programs are effective in decreasing both syringe sharing and HIV incidence in injection drug users. In addition, many NEPs are also beneficial because they provide other injection drug use-relevant services. There are several strategies that can be adopted in order to optimize the impact of needle exchange programs, at both the community and national levels. These include establishing NEPs in communities that need them, expanding and improving those that already exist, and implementing such programs on a larger national scale with the provision of federal funds.


Assuntos
Síndrome da Imunodeficiência Adquirida/prevenção & controle , Programas de Troca de Agulhas , Abuso de Substâncias por Via Intravenosa/complicações , Síndrome da Imunodeficiência Adquirida/transmissão , Humanos
15.
Cancer Res ; 60(15): 4030-2, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10945603

RESUMO

Nearly 6000 patients enrolled in four clinical trials of the National Wilms' Tumor Study Group during 1969-1995 were followed until death or for a median of 11.0 years of survival for the onset of renal failure (RF). Thirteen of 22 patients with Denys-Drash syndrome and 10 of 46 patients with the Wilms' tumor aniridia syndrome developed RF. The cumulative risks of RF at 20 years from Wilms' tumor diagnosis were 62% and 38%, respectively. Only 21 cases of RF were observed among 5358 patients with unilateral disease who did not have characteristic congenital genitourinary anomalies, and their risk was <1%. Although other explanations cannot be completely excluded, the high rate of RF in patients with the aniridia syndrome challenges the view that nephropathy is associated uniquely with missense mutations in the WT1 gene. It suggests the possibility of a further gradation in the spectrum of phenotypes associated with different WT1 mutations. Patients with Wilms' tumor and aniridia or genitourinary abnormalities should be followed closely throughout life for signs of nephropathy or RF.


Assuntos
Transtornos do Desenvolvimento Sexual/complicações , Glomerulosclerose Segmentar e Focal/complicações , Síndrome Nefrótica/complicações , Insuficiência Renal/etiologia , Síndrome WAGR/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Genitália Masculina/anormalidades , Humanos , Lactente , Masculino , Fatores de Risco , Síndrome
16.
Vet Parasitol ; 88(3-4): 261-8, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10714463

RESUMO

The insecticidal effects of the phenylpyrazole, fipronil, and a pyrethroid, beta-cyfluthrin, on larvae of the blowfly Lucilia sericata were determined in laboratory assays. When first stage larvae of L. sericata were reared on homogenized pig liver which had been treated with known amounts of test compounds, both fipronil and beta-cyfluthrin induced significant levels of mortality compared to acetone and water controls. However, fipronil was approximately 10 times more toxic than beta-cyfluthrin to L. sericata larvae following ingestion. Beta-cyfluthrin had little effect on mortality until concentrations of approximately 0.5 ppm were reached. In contrast, fipronil effected L. sericata mortality at a concentration of 0.05 ppm and 100% mortality was reached by 0.5 ppm. The lethal concentration (LC50) value for beta-cyfluthrin was 1.56 ppm as compared to 0.14 ppm for fipronil. Following contact of first and third stage larvae with cloth impregnated with known amounts of test compound, the mortality profiles of fipronil and beta-cyfluthrin were similar. At short contact times, the LC50 values for fipronil were lower than those for beta-cyfluthrin. However, at the highest contact time evaluated for the first stage larvae, 300 s, there was a reversal in this trend. The results suggest that the phenylpyrazole fipronil may represent a new potential insecticide for development against blowfly strike of sheep.


Assuntos
Dípteros , Inseticidas , Pirazóis , Piretrinas , Administração Tópica , Animais , Fígado/parasitologia , Nitrilas
17.
Hum Mutat ; 15(4): 332-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10737978

RESUMO

This is a report on the nature of the mutations in the PAX6 gene in twenty patients with aniridia. Five of the twenty patients had sporadic aniridia with deletions in chromosome 11p13. Three of the five had WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, mental retardation), and the other two had deletions whose breakpoints occurred between the PAX6 and the WT1 genes. Allelic losses at PAX6 were of paternal origin. The remaining fifteen patients with aniridia had intragenic mutations in the PAX6 gene, with mutations found from exon 5 to exon 12. Twelve cases of dysfunctional PAX6 were due to premature termination of the protein by nonsense mutations (five cases), splicing defect (one case), deletion (two cases), deletion-insertions (two cases), and tandem repeat insertions (two cases). One patient (P2) had a PAX6 protein with de novo in-frame deletion of alanine, arginine, and proline at codon positions 37, 38, and 39. These codons are in the paired box region, and codon 38 is in contact with the phosphate group of the sugar-phosphate backbone of the target DNA. Another patient (P8) had a single nucleotide transition at c.1182 (nucleotide number, Genbank accession #M93650, used as in Glaser et al. [1992]), which generated both a missense mutation (Q255H) and a splicing defect. A missense mutation was found at G387E in a third patient (P10). All observed mutations support the notion that haploinsufficiency in PAX6 results in aniridia and associated eye anomalies.


Assuntos
Aniridia/genética , Proteínas de Ligação a DNA/genética , Proteínas de Homeodomínio , Mutação/genética , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Proteínas de Ligação a DNA/deficiência , Proteínas do Olho , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Mutação de Sentido Incorreto , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados , Linhagem , Fenótipo , Proteínas Repressoras , Deleção de Sequência
18.
Chem Biol ; 7(1): 9-16, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10662681

RESUMO

BACKGROUND: Ring-opening metathesis polymerization (ROMP) is a powerful synthetic method for generating unique materials. The functional group tolerance of ruthenium ROMP initiators allows the synthesis of a wide range of biologically active polymers. We generated multivalent ligands that inhibit cell surface L-selectin, a protein that mediates lymphocyte homing and leukocyte recruitment in inflammation. We hypothesized that these ligands function through specific, multivalent binding to L-selection. To examine this and to develop a general method for synthesizing multivalent materials with end-labels, we investigated functionalized enol ethers as capping agents in ruthenium-initiated ROMP. RESULTS: We synthesized a bifunctional molecule that introduces a unique end group by terminating ruthenium-initiated ROMP reactions. This agent contains an enol ether at one end and a masked carboxylic acid at the other. We conjugated a fluorescein derivative to an end-capped neoglycopolymer that had previously been shown to inhibit L-selection function. We used fluorescence microscopy to visualize neoglycopolymer binding to cells displaying L-selectin. Our results suggest that the neoglycopolymers bind specifically to cell surface L-selectin through multivalent interactions. CONCLUSIONS: Ruthenium-initiated ROMP can be used to generate biologically active, multivalent ligands terminated with a latent functional group. The functionalized polymers can be labeled with a variety of molecular tags, including fluorescent molecules, biotin, lipids or antibodies. The ability to conjugate reporter groups to ROMP polymers using this strategy has broad applications in the material and biological sciences.


Assuntos
Receptores de Superfície Celular/efeitos dos fármacos , Carboidratos/química , Fluoresceínas/síntese química , Corantes Fluorescentes/síntese química , Células HL-60 , Humanos , Indicadores e Reagentes , Células Jurkat , Selectina L/química , Ligantes , Microscopia de Fluorescência , Ligação Proteica , Agregação de Receptores , Rutênio/química
19.
J Neurosci ; 20(2): 649-59, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10632594

RESUMO

The Drosophila trp gene encodes a light-activated Ca(2+) channel subunit, which is a prototypical member of a novel class of channel proteins. Previously identified trp mutants are all recessive, loss-of-function mutants characterized by a transient receptor potential and the total or near-total loss of functional TRP protein. Although retinal degeneration does occur in these mutants, it is relatively mild and slow in onset. We report herein a new mutant, Trp(P365), that does not display the transient receptor potential phenotype and is characterized by a substantial level of the TRP protein and rapid, semi-dominant degeneration of photoreceptors. We show that, in spite of its unusual phenotypes, Trp(P365) is a trp allele because a Trp(P365) transgene induces the mutant phenotype in a wild-type background, and a wild-type trp transgene in a Trp(P365) background suppresses the mutant phenotype. Moreover, amino acid alterations that could cause the Trp(P365) phenotype are found in the transmembrane segment region of the mutant channel protein. Whole-cell recordings clarified the mechanism underlying the retinal degeneration by showing that the TRP channels of Trp(P365) are constitutively active. Although several genes, when mutated, have been shown to cause retinal degeneration in Drosophila, the underlying mechanism has not been identified for any of them. The present studies provide evidence for a specific mechanism for massive degeneration of photoreceptors in Drosophila. Insofar as some human homologs of TRP are highly expressed in the brain, a similar mechanism could be a major contributor to degenerative disorders of the brain.


Assuntos
Substituição de Aminoácidos , Canais de Cálcio/genética , Mapeamento Cromossômico , Drosophila melanogaster/genética , Células Fotorreceptoras de Invertebrados/citologia , Células Fotorreceptoras de Invertebrados/fisiologia , Mutação Puntual , Sequência de Aminoácidos , Animais , Canais de Cálcio/química , Canais de Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Eletrorretinografia , Genes de Insetos , Humanos , Microscopia Confocal , Dados de Sequência Molecular , Degeneração Neural/genética , Fenótipo , Retina/ultraestrutura , Canais de Cátion TRPC
20.
Environ Microbiol ; 2(1): 91-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11243266

RESUMO

We performed the first field-scale atrazine remediation study in the United States using chemically killed, recombinant organisms. This field study compared biostimulation methods for enhancing atrazine degradation with a novel bioaugmentation protocol using a killed and stabilized whole-cell suspension of recombinant Escherichia coli engineered to overproduce atrazine chlorohyrolase, AtzA. AtzA dechlorinates atrazine, producing non-toxic and non-phytotoxic hydroxyatrazine. Soil contaminated by an accidental spill of atrazine (up to 29,000 p.p.m.) supported significant populations of indigenous microorganisms capable of atrazine catabolism. Laboratory experiments indicated that supplementing soil with carbon inhibited atrazine biodegradation, but inorganic phosphate stimulated atrazine biodegradation. A subsequent field-scale study consisting of nine (0.75m3) treatment plots was designed to test four treatment protocols in triplicate. Control plots contained moistened soil; biostimulation plots received 300p.p.m. phosphate; bioaugmentation plots received 0.5% (w/w) killed, recombinant E. coli cells encapsulating AtzA; and combination plots received phosphate plus the enzyme-containing cells. After 8 weeks, atrazine levels declined 52% in plots containing killed recombinant E. coli cells, and 77% in combination plots. In contrast, atrazine levels in control and biostimulation plots did not decline significantly. These data indicate that genetically engineered bacteria overexpressing catabolic genes significantly increased degradation in this soil heavily contaminated with atrazine.


Assuntos
Atrazina/metabolismo , Poluição Ambiental , Escherichia coli/enzimologia , Herbicidas/metabolismo , Hidrolases/metabolismo , Microbiologia do Solo , Biodegradação Ambiental , Escherichia coli/genética , Hidrolases/genética , Hidrólise , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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