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1.
BMC Prim Care ; 25(1): 153, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711031

RESUMO

BACKGROUND: Clinical practice guidelines (CPGs) synthesize high-quality information to support evidence-based clinical practice. In primary care, numerous CPGs must be integrated to address the needs of patients with multiple risks and conditions. The BETTER program aims to improve prevention and screening for cancer and chronic disease in primary care by synthesizing CPGs into integrated, actionable recommendations. We describe the process used to harmonize high-quality cancer and chronic disease prevention and screening (CCDPS) CPGs to update the BETTER program. METHODS: A review of CPG databases, repositories, and grey literature was conducted to identify international and Canadian (national and provincial) CPGs for CCDPS in adults 40-69 years of age across 19 topic areas: cancers, cardiovascular disease, chronic obstructive pulmonary disease, diabetes, hepatitis C, obesity, osteoporosis, depression, and associated risk factors (i.e., diet, physical activity, alcohol, cannabis, drug, tobacco, and vaping/e-cigarette use). CPGs published in English between 2016 and 2021, applicable to adults, and containing CCDPS recommendations were included. Guideline quality was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool and a three-step process involving patients, health policy, content experts, primary care providers, and researchers was used to identify and synthesize recommendations. RESULTS: We identified 51 international and Canadian CPGs and 22 guidelines developed by provincial organizations that provided relevant CCDPS recommendations. Clinical recommendations were extracted and reviewed for inclusion using the following criteria: 1) pertinence to primary prevention and screening, 2) relevance to adults ages 40-69, and 3) applicability to diverse primary care settings. Recommendations were synthesized and integrated into the BETTER toolkit alongside resources to support shared decision-making and care paths for the BETTER program. CONCLUSIONS: Comprehensive care requires the ability to address a person's overall health. An approach to identify high-quality clinical guidance to comprehensively address CCDPS is described. The process used to synthesize and harmonize implementable clinical recommendations may be useful to others wanting to integrate evidence across broad content areas to provide comprehensive care. The BETTER toolkit provides resources that clearly and succinctly present a breadth of clinical evidence that providers can use to assist with implementing CCDPS guidance in primary care.


Assuntos
Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , Prevenção Primária , Humanos , Atenção Primária à Saúde/normas , Prevenção Primária/normas , Canadá , Programas de Rastreamento/normas , Doença Crônica/prevenção & controle , Pessoa de Meia-Idade , Adulto , Idoso , Neoplasias/prevenção & controle , Neoplasias/diagnóstico
2.
Kans J Med ; 15: 131-134, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646255

RESUMO

Introduction: Use of tobacco products carries significant long-term health risks, and rates of smoking in persons living with HIV are as high as two to three times that of the general population. This study aimed to increase assessment of readiness to quit smoking and provide cessation counseling to patients receiving HIV care through an infectious disease clinic. Methods: This study was a pilot implementation in a single-center teaching hospital. In total, 603 active patients with HIV were followed in clinic at the time of the study start; of these, 79 were active tobacco smokers (13%) and eligible for the intervention. Providers were educated on recommendations for tobacco smoking cessation counseling, intervention strategies, and options for treatment. Patients who smoked tobacco were assessed for readiness to quit. Cessation counseling and tobacco cessation mediations or nicotine replacement were provided at the discretion of the patient and physician based on visit discussions. Primary outcome measures were increase in assessment of readiness to quit and in providing cessation counseling. Secondary measures included tabulation of the number of patients provided with a tobacco smoking cessation treatment and those with a successful quit episode. Results: There was a moderate increase in patients assessed for readiness to quit and who received tobacco smoking cessation counseling and treatment medications during the pilot. In total, 11 patients (8.7%) reported quitting smoking for at least two weeks. Conclusions: Additional work on streamlined mechanisms to identify tobacco use and provide efficient and effective tobacco smoking cessation counseling are needed in this high-risk population.

3.
PLoS One ; 15(7): e0236315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706791

RESUMO

The natural product nobiletin is a small molecule, widely studied with regard to its therapeutic effects, including in cancer cell lines and tumors. Recently, nobiletin has also been shown to affect circadian rhythms via their enhancement, resulting in protection against metabolic syndrome. We hypothesized that nobiletin's anti-oncogenic effects, such as prevention of cell migration and formation of anchorage independent colonies, are correspondingly accompanied by modulation of circadian rhythms. Concurrently, we wished to determine whether the circadian and anti-oncogenic effects of nobiletin differed across cancer cell lines. In this study, we assessed nobiletin's circadian and therapeutic characteristics to ascertain whether these effects depend on cell line, which here also varied in terms of baseline circadian rhythmicity. Three cell culture models where nobiletin's effects on cell proliferation and migration have been studied previously were evaluated: U2OS (bone osteosarcoma), which possesses robust circadian rhythms; MCF7 (breast adenocarcinoma), which has weak circadian rhythms; and MDA-MB-231 (breast adenocarcinoma), which is arrhythmic. We found that circadian, migration, and proliferative effects following nobiletin treatment were subtle in the U2OS and MCF7 cells. On the other hand, changes were clear in MDA-MB-231s, where nobiletin rescued rhythmicity and substantially reduced oncogenic features, specifically two-dimensional cell motility and anchorage-independent growth. Based on these results and those previously described, we posit that the effects of nobiletin are indeed cell-type dependent, and that a positive correlation may exist between nobiletin's circadian and therapeutic effects.


Assuntos
Antineoplásicos Fitogênicos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Flavonas , Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Flavonas/farmacologia , Flavonas/uso terapêutico , Humanos , Osteossarcoma/tratamento farmacológico
4.
Integr Cancer Ther ; 19: 1534735420924094, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32493076

RESUMO

Circadian rhythms are essential for controlling the cell cycle, cellular proliferation, and apoptosis, and hence are tightly linked to cell fate. Several recent studies have used small molecules to affect circadian oscillations; however, their concomitant cellular effects were not assessed, and they have not been compared under similar experimental conditions. In this work, we use five molecules, grouped into direct versus indirect effectors of the circadian clock, to modulate periods in a human osteosarcoma cell line (U2OS) and determine their influences on cellular behaviors, including motility and colony formation. Luciferase reporters, whose expression was driven via Bmal1- or Per2-promoters, were used to facilitate the visualization and quantitative analysis of circadian oscillations. We show that all molecules increase or decrease the circadian periods of Bmal1 and Per2 in a dose-dependent manner, but period length does not correlate with the extent of cell migration or proliferation. Nonetheless, molecules that affected circadian oscillations to a greater degree resulted in substantial influence on cellular behaviors (ie, motility and colony formation), which may also be attributable to noncircadian targets. Furthermore, we find that the ability and extent to which the molecules are able to affect oscillations is independent of whether they are direct or indirect modulators. Because of the numerous connections and feedback between the circadian clock and other pathways, it is important to consider the effects of both in assessing these and other compounds.


Assuntos
Relógios Circadianos , Diferenciação Celular , Proliferação de Células , Ritmo Circadiano , Humanos , Regiões Promotoras Genéticas
5.
Methods Enzymol ; 639: 115-140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32475398

RESUMO

Circadian rhythms are critical regulators of many physiological and behavioral functions. The use and abilities of small molecules to affect oscillations have recently received significant attention. These manipulations can be reversible and tunable, and have been used to study various biological mechanisms and molecular properties. Here, we outline procedures for assessment of cellular circadian changes following treatment with small molecules, using luminescent reporters. We describe reporter generation, luminometry experiments, and data analysis. Protocols for studies of accompanying effects on cells, including motility, viability, and anchorage-independent proliferation assays are also presented. As examples, we use indirubin-3'-oxime and two derivatives, 5-iodo-indirubin-3'-oxime and 5-sulfonic acid-indirubin-3'-oxime. In this case study, we analyze effects of these compounds on Bmal1 and Per2 (positive and negative core circadian elements) oscillations and provide step-by-step protocols for data analysis, including removal of trends from raw data, period estimations, and statistical analysis. The reader is provided with detailed protocols, and guidance regarding selection of and alternative approaches.


Assuntos
Ritmo Circadiano , Linhagem Celular Tumoral , Indóis
6.
BMJ Open ; 7(11): e016124, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29102984

RESUMO

OBJECTIVE: To develop and encourage the adoption of clinical practice guidelines (CPGs) for smoking cessation in Canada by engaging stakeholders in the adaptation of existing high-quality CPGs using principles of the ADAPTE framework. METHODS: An independent expert body in guideline review conducted a review and identified six existing CPGs, which met a priori criteria for quality and potential applicability to the local context. Summary statements were extracted and assigned a grade of recommendation and level of evidence by a second expert panel. Regional knowledge exchange brokers recruited additional stakeholders to build a multidisciplinary network of over 800 clinicians, researchers and decision-makers from across Canada. This interprofessional network and other stakeholders were offered various opportunities to provide input on the guideline both online and in person. We actively encouraged end-user input into the development and adaptation of the guidelines to ensure applicability to various practice settings and to promote adoption. RESULTS: The final guideline contained 24 summary statements along with supporting clinical considerations, across six topic area sections. The guideline was adopted by various provincial/territorial and national government and non-governmental organisations. CONCLUSIONS: This method can be applied in other jurisdictions to adapt existing high-quality smoking cessation CPGs to the local context and to facilitate subsequent adoption by various stakeholders.


Assuntos
Prática Clínica Baseada em Evidências/normas , Guias de Prática Clínica como Assunto , Abandono do Hábito de Fumar/métodos , Canadá , Atenção à Saúde/organização & administração , Humanos
7.
Nat Commun ; 7: 11693, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27243207

RESUMO

Analysing population genomic data from killer whale ecotypes, which we estimate have globally radiated within less than 250,000 years, we show that genetic structuring including the segregation of potentially functional alleles is associated with socially inherited ecological niche. Reconstruction of ancestral demographic history revealed bottlenecks during founder events, likely promoting ecological divergence and genetic drift resulting in a wide range of genome-wide differentiation between pairs of allopatric and sympatric ecotypes. Functional enrichment analyses provided evidence for regional genomic divergence associated with habitat, dietary preferences and post-zygotic reproductive isolation. Our findings are consistent with expansion of small founder groups into novel niches by an initial plastic behavioural response, perpetuated by social learning imposing an altered natural selection regime. The study constitutes an important step towards an understanding of the complex interaction between demographic history, culture, ecological adaptation and evolution at the genomic level.


Assuntos
Ecótipo , Evolução Molecular , Especiação Genética , Seleção Genética/genética , Orca/fisiologia , Adaptação Biológica/genética , Animais , Biópsia , Feminino , Interação Gene-Ambiente , Deriva Genética , Variação Genética/genética , Genética Populacional/métodos , Genoma , Genômica/métodos , Masculino , Filogenia , Isolamento Reprodutivo , Pele , Simpatria/genética
8.
Mol Ecol ; 24(15): 3964-79, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26087773

RESUMO

Global climate change during the Late Pleistocene periodically encroached and then released habitat during the glacial cycles, causing range expansions and contractions in some species. These dynamics have played a major role in geographic radiations, diversification and speciation. We investigate these dynamics in the most widely distributed of marine mammals, the killer whale (Orcinus orca), using a global data set of over 450 samples. This marine top predator inhabits coastal and pelagic ecosystems ranging from the ice edge to the tropics, often exhibiting ecological, behavioural and morphological variation suggestive of local adaptation accompanied by reproductive isolation. Results suggest a rapid global radiation occurred over the last 350 000 years. Based on habitat models, we estimated there was only a 15% global contraction of core suitable habitat during the last glacial maximum, and the resources appeared to sustain a constant global effective female population size throughout the Late Pleistocene. Reconstruction of the ancestral phylogeography highlighted the high mobility of this species, identifying 22 strongly supported long-range dispersal events including interoceanic and interhemispheric movement. Despite this propensity for geographic dispersal, the increased sampling of this study uncovered very few potential examples of ancestral dispersal among ecotypes. Concordance of nuclear and mitochondrial data further confirms genetic cohesiveness, with little or no current gene flow among sympatric ecotypes. Taken as a whole, our data suggest that the glacial cycles influenced local populations in different ways, with no clear global pattern, but with secondary contact among lineages following long-range dispersal as a potential mechanism driving ecological diversification.


Assuntos
Evolução Biológica , Mudança Climática , Variação Genética , Orca/genética , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Ecossistema , Ecótipo , Modelos Teóricos , Dados de Sequência Molecular , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Análise de Sequência de DNA
9.
Proc Natl Acad Sci U S A ; 111(37): 13319-24, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25161284

RESUMO

Packaging specific exogenous active proteins and DNAs together within a single viral-nanocontainer is challenging. The bacteriophage T4 capsid (100 × 70 nm) is well suited for this purpose, because it can hold a single long DNA or multiple short pieces of DNA up to 170 kb packed together with more than 1,000 protein molecules. Any linear DNA can be packaged in vitro into purified procapsids. The capsid-targeting sequence (CTS) directs virtually any protein into the procapsid. Procapsids are assembled with specific CTS-directed exogenous proteins that are encapsidated before the DNA. The capsid also can display on its surface high-affinity eukaryotic cell-binding peptides or proteins that are in fusion with small outer capsid and head outer capsid surface-decoration proteins that can be added in vivo or in vitro. In this study, we demonstrate that the site-specific recombinase cyclic recombination (Cre) targeted into the procapsid is enzymatically active within the procapsid and recircularizes linear plasmid DNA containing two terminal loxP recognition sites when packaged in vitro. mCherry expression driven by a cytomegalovirus promoter in the capsid containing Cre-circularized DNA is enhanced over linear DNA, as shown in recipient eukaryotic cells. The efficient and specific packaging into capsids and the unpackaging of both DNA and protein with release of the enzymatically altered protein-DNA complexes from the nanoparticles into cells have potential in numerous downstream drug and gene therapeutic applications.


Assuntos
Bacteriófago T4/química , Capsídeo/química , DNA/química , Expressão Gênica , Técnicas de Transferência de Genes , Integrases/metabolismo , Nanopartículas/química , Sítios de Ligação Microbiológicos , Sequência de Bases , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , DNA/isolamento & purificação , Empacotamento do DNA , DNA Circular/metabolismo , Citometria de Fluxo , Fluorescência , Humanos , Dados de Sequência Molecular , Plasmídeos/metabolismo , Coloração e Rotulagem , Transformação Genética
10.
CMAJ Open ; 2(1): E1-E10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25077119

RESUMO

BACKGROUND: The aim of the Building on Existing Tools to Improve Chronic Disease Prevention and Screening in Family Practice (BETTER) randomized controlled trial is to improve the primary prevention of and screening for multiple conditions (diabetes, cardiovascular disease, cancer) and some of the associated lifestyle factors (tobacco use, alcohol overuse, poor nutrition, physical inactivity). In this article, we describe how we harmonized the evidence-based clinical practice guideline recommendations and patient tools to determine the content for the BETTER trial. METHODS: We identified clinical practice guidelines and tools through a structured literature search; we included both indexed and grey literature. From these guidelines, recommendations were extracted and integrated into knowledge products and outcome measures for use in the BETTER trial. End-users (family physicians, nurse practitioners, nurses and dieticians) were engaged in reviewing the recommendations and tools, as well as tailoring the content to the needs of the BETTER trial and family practice. RESULTS: In total, 3-5 high-quality guidelines were identified for each condition; from these, we identified high-grade recommendations for the prevention of and screening for chronic disease. The guideline recommendations were limited by conflicting recommendations, vague wording and different taxonomies for strength of recommendation. There was a lack of quality evidence for manoeuvres to improve the uptake of guidelines among patients with depression. We developed the BETTER clinical algorithms for the implementation plan. Although it was difficult to identify high-quality tools, 180 tools of interest were identified. INTERPRETATION: The intervention for the BETTER trial was built by integrating existing guidelines and tools, and working with end-users throughout the process to increase the intervention's utility for practice. TRIAL REGISTRATION: ISRCTN07170460.

11.
J Med Chem ; 56(13): 5275-87, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23815100

RESUMO

In this study, we describe novel inhibitors against Francisella tularensis SchuS4 FabI identified from structure-based in silico screening with integrated molecular dynamics simulations to account for induced fit of a flexible loop crucial for inhibitor binding. Two 3-substituted indoles, 54 and 57, preferentially bound the NAD(+) form of the enzyme and inhibited growth of F. tularensis SchuS4 at concentrations near that of their measured Ki. While 57 was species-specific, 54 showed a broader spectrum of growth inhibition against F. tularensis , Bacillus anthracis , and Staphylococcus aureus . Binding interaction analysis in conjunction with site-directed mutagenesis revealed key residues and elements that contribute to inhibitor binding and species specificity. Mutation of Arg-96, a poorly conserved residue opposite the loop, was unexpectedly found to enhance inhibitor binding in the R96G and R96M variants. This residue may affect the stability and closure of the flexible loop to enhance inhibitor (or substrate) binding.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Francisella tularensis/efeitos dos fármacos , Indóis/farmacologia , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional/métodos , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/genética , Inibidores Enzimáticos/química , Francisella tularensis/genética , Francisella tularensis/crescimento & desenvolvimento , Humanos , Indóis/química , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
12.
PLoS One ; 7(11): e48674, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23139812

RESUMO

Observations of enhanced growth of melanized fungi under low-dose ionizing radiation in the laboratory and in the damaged Chernobyl nuclear reactor suggest they have adapted the ability to survive or even benefit from exposure to ionizing radiation. However, the cellular and molecular mechanism of fungal responses to such radiation remains poorly understood. Using the black yeast Wangiella dermatitidis as a model, we confirmed that ionizing radiation enhanced cell growth by increasing cell division and cell size. Using RNA-seq technology, we compared the transcriptomic profiles of the wild type and the melanin-deficient wdpks1 mutant under irradiation and non-irradiation conditions. It was found that more than 3000 genes were differentially expressed when these two strains were constantly exposed to a low dose of ionizing radiation and that half were regulated at least two fold in either direction. Functional analysis indicated that many genes for amino acid and carbohydrate metabolism and cell cycle progression were down-regulated and that a number of antioxidant genes and genes affecting membrane fluidity were up-regulated in both irradiated strains. However, the expression of ribosomal biogenesis genes was significantly up-regulated in the irradiated wild-type strain but not in the irradiated wdpks1 mutant, implying that melanin might help to contribute radiation energy for protein translation. Furthermore, we demonstrated that long-term exposure to low doses of radiation significantly increased survivability of both the wild-type and the wdpks1 mutant, which was correlated with reduced levels of reactive oxygen species (ROS), increased production of carotenoid and induced expression of genes encoding translesion DNA synthesis. Our results represent the first functional genomic study of how melanized fungal cells respond to low dose ionizing radiation and provide clues for the identification of biological processes, molecular pathways and individual genes regulated by radiation.


Assuntos
Adaptação Fisiológica/efeitos da radiação , Exophiala/fisiologia , Exophiala/efeitos da radiação , Radiação Ionizante , Adaptação Fisiológica/genética , Antioxidantes/metabolismo , Transporte Biológico/genética , Transporte Biológico/efeitos da radiação , Carotenoides/biossíntese , Ciclo Celular/genética , Ciclo Celular/efeitos da radiação , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Relação Dose-Resposta à Radiação , Exophiala/citologia , Exophiala/genética , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica/efeitos da radiação , Genes Fúngicos/genética , Melaninas/metabolismo , Fluidez de Membrana/genética , Fluidez de Membrana/efeitos da radiação , Viabilidade Microbiana/genética , Viabilidade Microbiana/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribossomos/genética , Ribossomos/efeitos da radiação , Transcriptoma/genética , Transcriptoma/efeitos da radiação , Regulação para Cima/genética , Regulação para Cima/efeitos da radiação , Água/metabolismo
13.
Biochemistry ; 51(6): 1199-212, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22257032

RESUMO

γ-Glutamyl transpeptidase (GGT) is a two-substrate enzyme that plays a central role in glutathione metabolism and is a potential target for drug design. GGT catalyzes the cleavage of γ-glutamyl donor substrates and the transfer of the γ-glutamyl moiety to an amine of an acceptor substrate or water. Although structures of bacterial GGT have revealed details of the protein-ligand interactions at the donor site, the acceptor substrate site is relatively undefined. The recent identification of a species-specific acceptor site inhibitor, OU749, suggests that these inhibitors may be less toxic than glutamine analogues. Here we investigated the donor and acceptor substrate preferences of Bacillus anthracis GGT (CapD) and applied computational approaches in combination with kinetics to probe the structural basis of the enzyme's substrate and inhibitor binding specificities and compare them with human GGT. Site-directed mutagenesis studies showed that the R432A and R520S variants exhibited 6- and 95-fold decreases in hydrolase activity, respectively, and that their activity was not stimulated by the addition of the l-Cys acceptor substrate, suggesting an additional role in acceptor binding and/or catalysis of transpeptidation. Rat GGT (and presumably HuGGT) has strict stereospecificity for L-amino acid acceptor substrates, while CapD can utilize both L- and D-acceptor substrates comparably. Modeling and kinetic analysis suggest that R520 and R432 allow two alternate acceptor substrate binding modes for L- and D-acceptors. R432 is conserved in Francisella tularensis, Yersinia pestis, Burkholderia mallei, Helicobacter pylori and Escherichia coli, but not in human GGT. Docking and MD simulations point toward key residues that contribute to inhibitor and acceptor substrate binding, providing a guide to designing novel and specific GGT inhibitors.


Assuntos
Proteínas de Bactérias/química , gama-Glutamiltransferase/química , Animais , Bacillus anthracis/enzimologia , Cápsulas Bacterianas/química , Cápsulas Bacterianas/genética , Cápsulas Bacterianas/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/genética , Domínio Catalítico , Biologia Computacional/métodos , Glutationa/metabolismo , Humanos , Ligantes , Camundongos , Ligação Proteica , Ratos , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Sulfonamidas/metabolismo , Sulfonamidas/farmacologia , Suínos , Tiadiazóis/metabolismo , Tiadiazóis/farmacologia , gama-Glutamiltransferase/antagonistas & inibidores , gama-Glutamiltransferase/genética
14.
Bioconjug Chem ; 22(4): 595-604, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21375348

RESUMO

Viruses are of particular interest as scaffolds for biotechnology applications given their wide range of shapes and sizes and the possibility to modify them with a variety of functional moieties to produce useful virus-based nanoparticles (VNPs). In order to develop functional VNPs for cell imaging and flow cytometry applications, we used the head of the T4 bacteriophage as a scaffold for bioconjugation of fluorescent dyes. Bacteriophage T4 is a double-stranded DNA virus with an elongated icosahedron head and a contractile tail. The head is ∼100 nm in length and ∼90 nm in width. The large surface area of the T4 head is an important advantage for the development of functional materials since it can accommodate significantly larger numbers of functional groups, such as fluorescent dyes, in comparison with other VNPs. In this study, Cy3 and Alexa Fluor 546 were chemically incorporated into tail-less T4 heads (T4 nanoparticles) for the first time, and the fluorescent properties of the dye-conjugated nanoparticles were characterized. The T4 nanoparticles were labeled with up to 19 000 dyes, and in particular, the use of Cy3 led to fluorescent enhancements of up to 90% compared to free Cy3. We also demonstrate that the dye-conjugated T4 nanoparticles are structurally stable and that they can be used as molecular probes for cell imaging and flow cytometry applications.


Assuntos
Bacteriófago T4/química , Rastreamento de Células/métodos , Citometria de Fluxo , Corantes Fluorescentes/química , Nanopartículas/química , Linhagem Celular Tumoral , Humanos , Propriedades de Superfície
15.
Evolution ; 65(1): 139-55, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20722729

RESUMO

Breakdown of self-incompatibility occurs repeatedly in flowering plants with important evolutionary consequences. In plant families in which self-incompatibility is mediated by S-RNases, previous evidence suggests that polyploidy may often directly cause self-compatibility through the formation of diploid pollen grains. We use three approaches to examine relationships between self-incompatibility and ploidy. First, we test whether evolution of self-compatibility and polyploidy is correlated in the nightshade family (Solanaceae), and find the expected close association between polyploidy and self-compatibility. Second, we compare the rate of breakdown of self-incompatibility in the absence of polyploidy against the rate of breakdown that arises as a byproduct of polyploidization, and we find the former to be greater. Third, we apply a novel extension to these methods to show that the relative magnitudes of the macroevolutionary pathways leading to self-compatible polyploids are time dependent. Over small time intervals, the direct pathway from self-incompatible diploids is dominant, whereas the pathway through self-compatible diploids prevails over longer time scales. This pathway analysis is broadly applicable to models of character evolution in which sequential combinations of rates are compared. Finally, given the strong evidence for both irreversibility of the loss of self-incompatibility in the family and the significant association between self-compatibility and polyploidy, we argue that ancient polyploidy is highly unlikely to have occurred within the Solanaceae, contrary to previous claims based on genomic analyses.


Assuntos
Poliploidia , Reprodução Assexuada , Solanaceae/genética , Evolução Biológica , Bases de Dados Genéticas , Genoma de Planta , Modelos Genéticos , Filogenia , Solanaceae/classificação , Solanaceae/fisiologia
16.
Anal Bioanal Chem ; 398(5): 1871-81, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20658281

RESUMO

With a view toward developing a rugged microflow cytometer, a sheath flow system was micromachined in hard plastic (polymethylmethacrylate) for analysis of particles and cells using optical detection. Six optical fibers were incorporated into the interrogation region of the chip, in which hydrodynamic focusing narrowed the core stream to ~35 µm × 40 µm. The use of a relatively large channel at the inlet as well as in the interrogation region (375 µm × 125 µm) successfully minimized the risk of clogging. The device could withstand pressures greater than 100 psi without leaking. Assays using both coded microparticles and cells were demonstrated using the microflow cytometer. Multiplexed immunoassays detected nine different bacteria and toxins using a single mixture of coded microspheres. A549 cancer cells processed with locked nucleic acid probes were evaluated using fluorescence in situ hybridization.


Assuntos
Bioensaio/instrumentação , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Bioensaio/métodos , Linhagem Celular Tumoral , Humanos , Imunoensaio , Microesferas , Polimetil Metacrilato/química
17.
Ther Deliv ; 1(3): 411-33, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22816144

RESUMO

The use of peptides to mediate the delivery and uptake of nanoparticle (NP) materials by mammalian cells has grown significantly over the past 10 years. This area of research has important implications for the development of new therapeutic materials and for the emerging field of NP-mediated drug delivery. In this review, we highlight recent advances in the delivery of various NPs by some of the more commonly employed cellular delivery peptides and discuss important related factors such as NP-peptide bioconjugation, uptake efficiency, intracellular fate and toxicity. We also highlight various demonstrations of therapeutic applications of NP-peptide conjugates where appropriate. The paper concludes with a brief forward-looking perspective discussing what can be expected as this field develops in the coming years.


Assuntos
Portadores de Fármacos , Nanomedicina , Nanopartículas , Peptídeos/metabolismo , Preparações Farmacêuticas/administração & dosagem , Tecnologia Farmacêutica/métodos , Animais , Transporte Biológico , Química Farmacêutica , Composição de Medicamentos , Técnicas de Transferência de Genes , Humanos , Nanomedicina/tendências , Peptídeos/química , Peptídeos/toxicidade , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Tecnologia Farmacêutica/tendências
18.
Clin Cancer Res ; 13(19): 5862-8, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17908980

RESUMO

PURPOSE: We used inflammatory breast cancer (IBC) as a model disease to investigate biological changes associated with an antiangiogenesis agent, SU5416, combined with doxorubicin. EXPERIMENTAL DESIGN: Patients with stage IIIB or IV IBC were treated neoadjuvantly with the combination of SU5416 and doxorubicin for induction therapy. The dose of SU5416 (administered on days 1 and 4, every 3 weeks) and doxorubicin (administered on day 1 every 3 weeks) were escalated in cohorts of three patients starting at 110 and 60 mg/m2, respectively, for a total of five cycles leading up to mastectomy. Patients underwent serial assessment (pharmacokinetic sampling, biopsy of breast, tumor blood flow dynamic contrast-enhanced magnetic resonance imaging, plasma angiogenesis, and endothelial cell damage markers) prior to treatment, at the end of cycles no. 2 and no. 5, and after mastectomy. RESULTS: Eighteen patients were enrolled; neutropenia was dose-limiting, and overall median survival was not reached (50 months of study follow-up). Four patients (22%) experienced congestive heart failure, which resolved and were likely attributable to a smaller volume of distribution and higher Cmax of doxorubicin in combination with SU5416. We did observe a significant decline in tumor blood flow using Kep calculated by Brix (pretreatment versus post-cycle no. 5; P = 0.033), trend for a decline in tumor microvessel density after treatment, and low baseline levels of soluble intracellular adhesion molecule were associated with improved event-free survival. CONCLUSIONS: This study showed evidence of an unfavorable cardiac interaction between SU5416 and doxorubicin, which prohibits further investigation of this combination. However, this study supports the importance of using IBC as a model for investigating angiogenesis inhibitors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Doxorrubicina/administração & dosagem , Indóis/administração & dosagem , Neovascularização Patológica/patologia , Pirróis/administração & dosagem , Adulto , Idoso , Inibidores da Angiogênese/farmacologia , Intervalo Livre de Doença , Feminino , Humanos , Inflamação , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Resultado do Tratamento
19.
Clin Cancer Res ; 11(21): 7938-44, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16278419

RESUMO

PURPOSE: To determine the biological modulatory dose of SU5416, we employed a novel trial design, where "dose de-escalation" was based on demonstrable biological changes observed at the maximum tolerated dose. If such an effect was shown, dose de-escalation to a predefined dose level would occur to determine if the lower dose exhibited the same amount of pharmacodynamic effect as the higher dose. EXPERIMENTAL DESIGN: Ten patients with advanced solid tumors were enrolled at each dose level. One of the following pharmacodynamic effects was considered significant: (a) a 35% decrease in microvessel density in sequential tumor biopsies and (b) a 35% decrease in blood flow within tumor as assessed by dynamic contrast-enhanced magnetic resonance imaging. In addition, soluble E-selectin, soluble intercellular adhesion molecule, soluble vascular cell adhesion molecule, and plasma vascular endothelial growth factor were measured sequentially. RESULTS: Nineteen patients were enrolled. Sequential tumor biopsies in all evaluable patients showed an increase in microvessel density. Only one patient met the intended pharmacodynamic end point of >35% reduction in blood flow. There was a significant increase in both soluble E-selectin and soluble intercellular adhesion molecule levels pretreatment versus levels at the time of removal of patients from study (P = 0.04 and P = 0.0007, respectively). Levels of serum fibrinogen rose with therapy. There was a trend toward increase in plasma vascular endothelial growth factor levels. CONCLUSION: SU5416 does not result in decreased blood flow in tumors or a decrease in microvessel density. This corresponds to the lack of clinical activity seen with this agent. Our clinical trial design termed dose de-escalation is a novel approach to determine the in vivo biological effects of targeted therapies in cancer patients.


Assuntos
Inibidores da Angiogênese/farmacologia , Indóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirróis/farmacologia , Adulto , Idoso , Biópsia , Densidade Óssea , Adesão Celular , Moléculas de Adesão Celular , Meios de Contraste/farmacologia , Selectina E/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Cinética , Imageamento por Ressonância Magnética/métodos , Masculino , Dose Máxima Tolerável , Microcirculação , Pessoa de Meia-Idade , Transplante de Neoplasias , Perfusão , Fatores de Tempo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Mol Ecol ; 14(11): 3353-71, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16156808

RESUMO

We present the first description of phylogeographic structure among Cuvier's beaked whales (Ziphius cavirostris) worldwide using mitochondrial DNA (mtDNA) control region sequences obtained from strandings (n = 70), incidental fisheries takes (n = 11), biopsy (n = 1), and whale-meat markets (n = 5). Over a 290-base pair fragment, 23 variable sites defined 33 unique haplotypes among the total of 87 samples. Nucleotide diversity at the control region was relatively low (pi = 1.27%+/- 0.723%) compared to wide-ranging baleen whales, but higher than strongly matrifocal sperm, pilot and killer whales. Phylogenetic reconstruction using maximum likelihood revealed four distinct haplotype groups, each of which displayed strong frequency differences among ocean basins, but no reciprocal monophyly or fixed character differences. Consistent with this phylogeographic pattern, an analysis of molecular variance showed high levels of differentiation among ocean basins (F(ST) = 0.14, Phi ST = 0.42; P < 0.001). Estimated rates of female migration among ocean basins were low (generally < or = 2 individuals per generation). Regional sample sizes were too small to detect subdivisions within oceans except in the North Atlantic, where the Mediterranean Sea (n = 12) was highly differentiated due to the presence of two private haplotypes. One market product purchased in South Korea grouped with other haplotypes found only in the North Atlantic, suggesting a violation of current agreements banning international trade in cetacean species. Together, these results demonstrate a high degree of isolation and low maternal gene flow among oceanic, and in some cases, regional populations of Cuvier's beaked whales. This has important implications for understanding the threats of human impact, including fisheries by-catch, direct hunting, and disturbance or mortality from anthropogenic sound.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Filogenia , Baleias/genética , Análise de Variância , Animais , Sequência de Bases , Conservação dos Recursos Naturais , Primers do DNA , Geografia , Haplótipos/genética , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Oceanos e Mares , Dinâmica Populacional , Análise de Sequência de DNA
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