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1.
Stud Health Technol Inform ; 310: 1542-1543, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38269736

RESUMO

This study assesses how effective gamification in smartphone apps is at enhancing lifestyle and cardiometabolic health in adults at risk of cardiovascular disease. Using a systematic review of six databases, it looked at trials that compared gamified and traditional interventions. Although apps scored highly for functionality, averaging a 4.07 rating, they lacked focus on user engagement. The study reveals that gamification can aid in achievable lifestyle changes and improve cardiometabolic factors, providing insights for future digital health approaches targeting CVD risk reduction.


Assuntos
Doenças Cardiovasculares , Aplicativos Móveis , Adulto , Humanos , Doenças Cardiovasculares/prevenção & controle , Smartphone , Estilo de Vida , Metaboloma
2.
JMIR Res Protoc ; 12: e46082, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37782531

RESUMO

BACKGROUND: Achieving the weekly physical activity recommendations of at least 150-300 minutes of moderate-intensity or 75-150 minutes of vigorous-intensity aerobic exercise is important for reducing cardiometabolic risk, but evidence shows that most people struggle to meet these goals, particularly in the mid to long term. OBJECTIVE: The Messages Improving Resting Heart Health (MIRTH) study aims to determine if (1) sending daily motivational messages through a research app is effective in improving motivation and in promoting adherence to physical activity recommendations in men and women with coronary heart disease randomized to a 12-month intensive lifestyle intervention, and (2) the time of the day when the message is delivered impacts compliance with exercise training. METHODS: We will conduct a single-center, microrandomized trial. Participants will be randomized daily to either receive or not receive motivational messages over two 90-day periods at the beginning (phase 1: months 4-6) and at the end (phase 2: months 10-12) of the Lifestyle Vulnerable Plaque Study. Wrist-worn devices (Fitbit Inspire 2) and Bluetooth pairing with smartphones will be used to passively collect data for proximal (ie, physical activity duration, steps walked, and heart rate within 180 minutes of receiving messages) and distal (ie, change values for resting heart rate and total steps walked within and across both phases 1 and 2 of the trial) outcomes. Participants will be recruited from a large academic cardiology office practice (Central Sydney Cardiology) and the Royal Prince Alfred Hospital Departments of Cardiology and Radiology. All clinical investigations will be undertaken at the Charles Perkins Centre Royal Prince Alfred clinic. Individuals aged 18-80 years (n=58) with stable coronary heart disease who have low attenuation plaques based on a coronary computed tomography angiography within the past 3 months and have been randomized to an intensive lifestyle intervention program will be included in MIRTH. RESULTS: The Lifestyle Vulnerable Plaque Study was funded in 2020 and started enrolling participants in February 2022. Recruitment for MIRTH commenced in November 2022. As of September 2023, 2 participants were enrolled in the MIRTH study and provided baseline data. CONCLUSIONS: This MIRTH microrandomized trial will represent the single most detailed and integrated analysis of the effects of a comprehensive lifestyle intervention delivered through a customized mobile health app on smart devices on time-based motivational messaging for patients with coronary heart disease. This study will also help inform future studies optimizing for just-in-time adaptive interventions. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12622000731796; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382861. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/46082.

3.
JAMA Netw Open ; 6(7): e2325658, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37490288

RESUMO

IMPORTANCE: Plant-based diets are known to improve cardiometabolic risk in the general population, but their effects on people at high risk of cardiovascular diseases (CVDs) remain inconclusive. OBJECTIVE: To assess the association of vegetarian diets with major cardiometabolic risk factors, including low-density lipoprotein cholesterol (LDL-C), hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and body weight in people with or at high risk of CVDs. DATA SOURCES: This meta-analysis was registered before the study was conducted. Systematic searches performed included Embase, MEDLINE, CINAHL, and CENTRAL from inception until July 31, 2021. STUDY SELECTION: Eligible randomized clinical trials (RCTs) that delivered vegetarian diets in adults with or at high risk of CVDs and measured LDL-C, HbA1c or SBP were included. Of the 7871 records screened, 29 (0.4%; 20 studies) met inclusion criteria. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently extracted data including demographics, study design, sample size, and diet description, and performed risk of bias assessment. A random-effects model was used to assess mean changes in LDL-C, HbA1c, SBP, and body weight. The overall certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool. MAIN OUTCOMES AND MEASURES: Mean differences between groups in changes (preintervention vs postintervention) of LDL-C, HbA1c, and SBP; secondary outcomes were changes in body weight and energy intake. RESULTS: Twenty RCTs involving 1878 participants (range of mean age, 28-64 years) were included, and mean duration of intervention was 25.4 weeks (range, 2 to 24 months). Four studies targeted people with CVDs, 7 focused on diabetes, and 9 included people with at least 2 CVD risk factors. Overall, relative to all comparison diets, meta-analyses showed that consuming vegetarian diets for an average of 6 months was associated with decreased LDL-C, HbA1c, and body weight by 6.6 mg/dL (95% CI, -10.1 to -3.1), 0.24% (95% CI, -0.40 to -0.07), and 3.4 kg (95% CI, -4.9 to -2.0), respectively, but the association with SBP was not significant (-0.1 mm Hg; 95% CI, -2.8 to 2.6). The GRADE assessment showed a moderate level of evidence for LDL-C and HbA1c reduction. CONCLUSIONS AND RELEVANCE: In this study, consuming a vegetarian diet was associated with significant improvements in LDL-C, HbA1c and body weight beyond standard therapy in individuals at high risk of CVDs. Additional high-quality trials are warranted to further elucidate the effects of healthy plant-based diets in people with CVDs.


Assuntos
Doenças Cardiovasculares , Adulto , Humanos , Pessoa de Meia-Idade , LDL-Colesterol , Hemoglobinas Glicadas , Vegetarianos , Projetos de Pesquisa , Peso Corporal
5.
Cureus ; 14(8): e28060, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36127980

RESUMO

INTRODUCTION:  The recent multi-nation outbreaks of human monkeypox in non-endemic areas have created an emerging public health issue. Medical students who will become future healthcare providers are directly associated with community people and can easily sensitize the general population, so it is crucial to assess their degree of knowledge and attitudes regarding recently emerging infections or pathogens. However, studies on medical students' perception of the monkeypox virus are scarce in Saudi Arabia. Therefore, the objective of this study was to assess the monkeypox virus-related knowledge and attitudes among medical students in the country. METHODS: A cross-sectional study was conducted from May to July 2022 among undergraduate medical students at King Khalid University, Abha, Saudi Arabia. A systematic random sampling technique was applied to select the study participants. A self-administered questionnaire was used to gather data on sociodemographic characteristics, knowledge and attitudes toward the monkeypox virus. Descriptive statistics and Chi-square tests were performed. RESULTS: A total of 314 medical students were recruited for this study. The findings from this study showed that the vast majority of medical students (72%) had poor knowledge about the monkeypox virus. Respondents' age, grade point average (GPA), fathers' education level, and training received about the monkeypox virus were significantly associated with the level of knowledge about the monkeypox virus (p < 0.05). Nearly half of the respondents (45.9%) agreed that the monkeypox virus could be transmitted to Saudi Arabia. Overall, this study showed that the awareness levels regarding the monkeypox virus were significantly higher among seniors as compared to junior students. CONCLUSION: The study found poor knowledge of the monkeypox virus among currently enrolled medical students in the country's highest-ranked medical school. This finding emphasizes the urgent need to increase their knowledge because controlling outbreaks requires significant cooperation from knowledgeable and skilled healthcare providers.

6.
Bioorg Med Chem Lett ; 28(13): 2270-2274, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29803730

RESUMO

The synthesis of steroid hormones is critical to human physiology and improper regulation of either the synthesis of these key molecules or activation of the associated receptors can lead to disease states. This has led to intense interest in developing compounds capable of modulating the synthesis of steroid hormones. Compounds capable of inhibiting Cyp19 (Aromatase), a key enzyme in the synthesis of estrogens, have been successfully employed as breast cancer therapies, while inhibitors of Cyp17 (17α-hydroxylase-17,20-lyase), a key enzyme in the synthesis of glucocorticoids, mineralocorticoids and steroidal sex hormones, are a key component of prostate cancer therapy. Inhibition of CYP17 has also been suggested as a possible target for the treatment of Cushing Syndrome and Metabolic Syndrome. We have identified two novel series of stilbene based CYP17 inhibitors and demonstrated that exemplary compounds in these series have pharmacokinetic properties consistent with orally delivered drugs. These findings suggest that compounds in these classes may be useful for the treatment of diseases and conditions associated with improper regulation of glucocorticoids synthesis and glucocorticoids receptor activation.


Assuntos
Inibidores das Enzimas do Citocromo P-450/farmacocinética , Desenho de Fármacos , Piperazinas/farmacocinética , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Estilbenos/farmacocinética , Animais , Inibidores das Enzimas do Citocromo P-450/síntese química , Inibidores das Enzimas do Citocromo P-450/química , Cobaias , Meia-Vida , Microssomos Hepáticos/metabolismo , Piperazinas/síntese química , Piperazinas/química , Estereoisomerismo , Estilbenos/síntese química , Estilbenos/química , Relação Estrutura-Atividade
7.
Anal Biochem ; 545: 78-83, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29360440

RESUMO

Tropomyosin-related kinase A (TRKA) fusion was originally detected in colorectal carcinoma that had resulted in expression of the oncogenic chimeric protein TPM3-TRKA. Lately, many more rearrangements in TRK family of kinases generating oncogenic fusion proteins have been identified. These genetic rearrangements usually result in fusion of cytoplasmic kinase domain of TRK to another gene of interest resulting in constitutive kinase activity. Estimation of TRK inhibitor potency in a cellular context is required for drug discovery programs and is measured by receptor phosphorylation levels upon compound administration. However, since a large chunk of the TRK protein is lost in this rearrangement, it's difficult to set up sandwich ELISA for detection of receptor phosphorylation in any cell assay harboring these fusion proteins. In order to address this issue, we developed a novel and robust in-cell ELISA method which quantifies the phosphorylation of TRK kinase (Tyr 674/675) within the KM12 cells. This cell based method is more versatile & economical than conventional ELISA using engineered overexpressing cell line and/or western blot methods. Performance reliability & robustness for the validated assay were determined by %CV and Z factor in assays with reference molecule larotrectinib. This in-cell ELISA method can be used with any TRKA rearranged oncogenic fusion cell type and can be extended to other TRK isoforms as well. We have used this assay to screen novel molecules in KM12 cells and to study pharmacodynamic properties of compounds in TRKA signaling.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Inibidores de Proteínas Quinases/farmacologia , Receptor trkA/antagonistas & inibidores , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Receptor trkA/genética , Receptor trkA/metabolismo , Relação Estrutura-Atividade
8.
J Immunoassay Immunochem ; 38(6): 663-674, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29035165

RESUMO

Phosphatidylinositol-3 kinase (PI3K) pathway regulates multiple cellular functions involving cell survival, growth, motility proliferation, apoptosis, and adhesion. These are deregulated in various diseases such as cancer, atherosclerosis, and inflammation. PI3Ks phosphorylate phosphatidylinositol 4,5-biphosphate (PIP2) yielding phosphatidylinositol 3, 4, 5 triphosphate (PIP3) which in turn activate AKT kinase (serine/threonine kinase), the central enzyme in regulation of metabolic functions. Due to their implications in disease pathophysiology, PI3K/AKT inhibitors became attractive targets for pharmaceutical industries. In order to assess the functional response generated by PI3K inhibitors, an appropriate cell-based screening system is essential in any screening cascade. Here we report the development of highly sensitive in-vitro cell-based kinase ELISA which quantifies the phosphorylated AKT kinase (serine 473) and total AKT kinase directly within the cells upon compound treatment. PI3Kß overexpressing NIH3T3 cells stimulated by lysophosphatidic acid was used for PI3K/Akt pathway activation. Assay performance reliability and robustness were determined by percentage coefficient of variation (%CV) and Z factor which demonstrated an excellent agreement with assay guidelines. This 96-well plate medium throughput assay methodology was used to screen novel molecules and proved a commendable tool to study the mechanism of action property and target engagement of novel PI3K inhibitors in drug discovery.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Cromonas/farmacologia , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática/normas , Lisofosfolipídeos/farmacologia , Camundongos , Morfolinas/farmacologia , Células NIH 3T3 , Fosfatidilinositol 3-Quinases/análise , Proteínas Proto-Oncogênicas c-akt/análise , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Pirimidinonas/farmacologia , Relação Estrutura-Atividade
9.
Bioorg Med Chem Lett ; 26(23): 5825-5829, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27789139

RESUMO

Metabolic Syndrome, also referred to as 'Syndrome X' or 'Insulin Resistance Syndrome,' remains a major, unmet medical need despite over 30years of intense effort. Recent research suggests that there may be a causal link between this condition and abnormal glucocorticoid processing. Specifically, dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis leads to increased systemic cortisol concentrations. Cushing' syndrome, a disorder that is also typified by a marked elevation in levels of cortisol, produces clinical symptomology that is similar to those observed in MetS, and they can be alleviated by decreasing circulating cortisol concentrations. As a result, it has been suggested that decreasing systemic cortisol concentration might have a positive impact on the progression of MetS. This could be accomplished through inhibition of enzymes in the cortisol synthetic pathway, 11ß-hydroxylase (Cyp11B1), 17α-hydroxylase-C17,20-lyase (Cyp17), and 21-hydroxylase (Cyp21). We have identified a series of novel sulfonamide analogs of (2S,4R)-Ketoconazole that are potent inhibitors of these enzymes. In addition, selected members of this class of compounds have pharmacokinetic properties consistent with orally delivered drugs, making them well suited to further investigation as potential therapies for MetS.


Assuntos
Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacologia , Cetoconazol/análogos & derivados , Cetoconazol/farmacologia , Síndrome Metabólica/tratamento farmacológico , Sulfonamidas/química , Sulfonamidas/farmacologia , Animais , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Desenho de Fármacos , Feminino , Cobaias , Humanos , Cetoconazol/farmacocinética , Masculino , Síndrome Metabólica/enzimologia , Sulfonamidas/farmacocinética
10.
Expert Opin Drug Discov ; 10(2): 171-86, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25547459

RESUMO

INTRODUCTION: Phosphoinositide 3-kinases (PI3Ks) constitute one of the most important signaling pathways, playing a vital role in cellular differentiation and proliferation with a key function in cellular receptor triggered signal transduction downstream of tyrosine kinase receptors and/or G-protein coupled receptors. PI3K promotes cell survival proliferation, protein synthesis and glucose metabolism by generating secondary messengers phospholipid phosphatidyl 3,4,5-triphosphate and signaling via AKT/mTOR regulation. Deregulation of PI3K pathways have been observed in cancer, diabetes, neurological and inflammatory diseases and is an attractive target for pharmaceutical industries. AREAS COVERED: In this review, the authors explain different PI3K assay methodologies. Furthermore, the authors summarize the techno-scientific principles and their utility in profiling novel chemical entities against PI3Ks. Specifically, the authors compare different PI3K assay formats explaining their mode of detection as well as their advantages and limitations for drug discovery efforts. EXPERT OPINION: Developing lipid (PI3K) kinase assays involves significant effort and a rational understanding is needed due to the intrinsic lipidic nature of phospholipid phosphatidyl 4,5-biphosphate, which is used as an in vitro substrate for assays with PI3K isoforms. The assay of choice should be versatile, homogenous and definitely adaptable for high-throughput screening campaigns. Additionally, these assays are expected to dissect the mechanism of action of novel compounds (inhibitor characterization) against PI3K. Existing methods provide the versatility to medicinal chemists such that they can choose one or more assay platform to progress their compounds while profiling and/or inhibitor characterization.


Assuntos
Descoberta de Drogas/métodos , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Ensaios de Triagem em Larga Escala/instrumentação , Humanos , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato
11.
Anal Biochem ; 449: 132-8, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24380788

RESUMO

The phosphatidylinositol 3-kinases (PI3Ks) are lipid kinases that regulate the cellular signal transduction pathways involved in cell growth, proliferation, survival, apoptosis, and adhesion. Deregulation of these pathways are common in oncogenesis, and they are known to be altered in other metabolic disorders as well. Despite its huge potential as an attractive target in these diseases, there is an unmet need for the development of a successful inhibitor. Unlike protein kinase inhibitors, screening for lipid kinase inhibitors has been challenging. Here we report, for the first time, the development of a radioactive lipid kinase screening platform using a phosphocellulose plate that involves transfer of radiolabeled [γ-(32)P]ATP to phosphatidylinositol 4,5-phosphate forming phosphatidylinositol 3,4,5-phosphate, captured on the phosphocellulose plate. Enzyme kinetics and inhibitory properties were established in the plate format using standard inhibitors, such as LY294002, TGX-221, and wortmannin, having different potencies toward PI3K isoforms. ATP and lipid apparent Km for both were determined and IC50 values generated that matched the historical data. Here we report the use of a phosphocellulose plate for a lipid kinase assay (PI3Kß as the target) as an excellent platform for the identification of novel chemical entities in PI3K drug discovery.


Assuntos
Celulose/análogos & derivados , Ensaios Enzimáticos/instrumentação , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Trifosfato de Adenosina/metabolismo , Celulose/química , Avaliação Pré-Clínica de Medicamentos/instrumentação , Desenho de Equipamento , Humanos , Papel , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/metabolismo
12.
PLoS One ; 7(2): e31417, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363644

RESUMO

In vivo analysis of Drosophila melanogaster has enhanced our understanding of many biological processes, notably the mechanisms of heredity and development. While in vivo analysis of mutants has been a strength of the field, analyzing fly cells in culture is valuable for cell biological, biochemical and whole genome approaches in which large numbers of homogeneous cells are required. An efficient genetic method to derive Drosophila cell lines using expression of an oncogenic form of Ras (Ras(V12)) has been developed. Mutations in tumor suppressors, which are known to cause cell hyperproliferation in vivo, could provide another method for generating Drosophila cell lines. Here we screened Drosophila tumor suppressor mutations to test if they promoted cell proliferation in vitro. We generated primary cultures and determined when patches of proliferating cells first emerged. These cells emerged on average at 37 days in wild-type cultures. Using this assay we found that a Pten mutation had a strong effect. Patches of proliferating cells appeared on average at 11 days and the cultures became confluent in about 3 weeks, which is similar to the timeframe for cultures expressing Ras(V12). Three Pten mutant cell lines were generated and these have now been cultured for between 250 and 630 cell doublings suggesting the life of the mutant cells is likely to be indefinite. We conclude that the use of Pten mutants is a powerful means to derive new Drosophila cell lines.


Assuntos
Proteínas de Drosophila/deficiência , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/enzimologia , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/metabolismo , Animais , Bioensaio , Linhagem Celular , Proliferação de Células , Hiperplasia , Proteínas Mutantes/metabolismo , Mutação/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fatores de Tempo , Proteínas Supressoras de Tumor/metabolismo , Proteínas ras/metabolismo
13.
J Cell Sci ; 121(Pt 20): 3335-46, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18827006

RESUMO

Previously, we showed that Abl family tyrosine kinases are activated by growth factors, and Abl is required for transition from G1 to S phase during PDGF-mediated proliferation. Here, we show that the SHP-2 tyrosine phosphatase, which acts to promote proliferation in response to cytokines and growth factors, is a novel substrate of endogenous Abl kinases during growth factor-mediated cellular proliferation. Using a pharmacological inhibitor and RNAi, we show that endogenous Abl kinases phosphorylate SHP-2 on Y580, and induce sustained activation of ERK kinases in response to growth factor stimulation in fibroblasts. Consistent with these data, SHP-2 is required for Abl-dependent PDGF-mediated proliferation since expression of an activated form of SHP-2 rescues the ability of Abl-Arg null fibroblasts to transit from G1 to S phase, whereas inhibition of SHP-2 signaling reduces the ability of Abl kinases to rescue the proliferation defect. Abl kinases also indirectly mediate phosphorylation of SHP-2 on Y63 and Y279, which are frequent sites of germline mutation in two cancer susceptibility syndromes. Significantly, we demonstrate that phosphorylation of SHP-2 on Y279 downregulates growth factor-induced sustained ERK activation and proliferation, supporting a role for Abl kinases not only in potentiating growth factor-mediated SHP-2 signaling, but also in negative-feedback regulation.


Assuntos
Fase G1/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Fase S/fisiologia , Transdução de Sinais/fisiologia , Animais , Fase G1/efeitos dos fármacos , Humanos , Camundongos , Células NIH 3T3 , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Proto-Oncogênicas c-abl/genética , Fase S/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
14.
PLoS Genet ; 4(8): e1000142, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18670627

RESUMO

Analysis of cells in culture has made substantial contributions to biological research. The versatility and scale of in vitro manipulation and new applications such as high-throughput gene silencing screens ensure the continued importance of cell-culture studies. In comparison to mammalian systems, Drosophila cell culture is underdeveloped, primarily because there is no general genetic method for deriving new cell lines. Here we found expression of the conserved oncogene Ras(V12) (a constitutively activated form of Ras) profoundly influences the development of primary cultures derived from embryos. The cultures become confluent in about three weeks and can be passaged with great success. The lines have undergone more than 90 population doublings and therefore constitute continuous cell lines. Most lines are composed of spindle-shaped cells of mesodermal type. We tested the use of the method for deriving Drosophila cell lines of a specific genotype by establishing cultures from embryos in which the warts (wts) tumor suppressor gene was targeted. We successfully created several cell lines and found that these differ from controls because they are primarily polyploid. This phenotype likely reflects the known role for the mammalian wts counterparts in the tetraploidy checkpoint. We conclude that expression of Ras(V12) is a powerful genetic mechanism to promote proliferation in Drosophila primary culture cells and serves as an efficient means to generate continuous cell lines of a given genotype.


Assuntos
Técnicas de Cultura de Células/métodos , Linhagem Celular Transformada/fisiologia , Drosophila/citologia , Drosophila/genética , Animais , Linhagem Celular/classificação , Proliferação de Células , Drosophila/embriologia , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Feminino , Expressão Gênica , Genótipo , Cariotipagem , Masculino , Proteína Oncogênica p21(ras)/genética , Proteína Oncogênica p21(ras)/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
15.
Int J Cancer ; 117(5): 786-93, 2005 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-15981211

RESUMO

The role of 3 p53 polymorphisms (16 bp duplication at intron 3, codon 72 Arg/Pro and intron 6 NciI RFLP at np 13494) as potential markers for indicating cancer risk remains inconclusive. In our case-control study consisting of 197 leukoplakia and 310 oral squamous cell carcinoma (SCC) patients and 348 controls, genotype frequencies at these 3 p53 loci were determined by PCR-RFLP method and analyzed by multiple logistic regression to determine the risks of the diseases. The 2/2 genotype at codon 72 of p53 was at risk for developing leukoplakia (OR = 1.6, 95% CI 1.1-2.3), whereas the combination of 1/2 and 2/2 genotypes at intron 3 and 1/1 and 1/2 genotypes at intron 6 conferred a protective effect against leukoplakia and oral SCC development, respectively (OR = 0.5, 95% CI 0.4-0.8 and OR = 0.6, 95% CI 0.5-0.9, respectively). When subjects were stratified according to specific tobacco habit, the risk/protection estimates improved significantly in some cases. Specifically, the exclusive smokers with p53 codon 72 2/2 genotype showed a higher risk of developing leukoplakia (OR = 2.7, 95% CI 1.2-6.3). Furthermore, a particular p53 haplotype 1-2-2 was at risk for both tobacco-associated leukoplakia and oral SCC (OR = 1.5, 95% CI 1.1-1.9 and OR = 1.3, 95% CI 1.1-1.7, respectively). Our results show that both specific p53 genotype and haplotype can indicate risk of tobacco-associated leukoplakia, but risk of development of tobacco-associated oral SCC can be predicted by specific p53 haplotype only.


Assuntos
Carcinoma de Células Escamosas/etiologia , Genes p53 , Haplótipos , Leucoplasia/etiologia , Neoplasias Bucais/etiologia , Nicotiana/efeitos adversos , Estudos de Casos e Controles , Genótipo , Humanos , Índia , Medição de Risco
16.
Mol Vis ; 8: 367-71, 2002 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-12368717

RESUMO

PURPOSE: Glaucoma is a complex neurodegenerative disorder of the eye. Primary Open Angle Glaucoma (POAG) is the most common type, accounting for over half of the total cases. Recently, a significant difference in the distribution of the codon 72 polymorphism of the tumor suppressor gene p53 between control subjects and POAG patients of Chinese origin (p=0.00782) was demonstrated. The proline residue at codon 72 of the p53 gene was significantly over represented in the POAG patients relative to healthy controls. The purpose of this study was to investigate whether the reported association between the p53 polymorphism and POAG is a common phenomenon irrespective of geographical location or ethnicity of the population. METHODS: Sixty seven unrelated POAG patients, ranging from 10-65 years of age (mean+/-SD of 41.16+/-18.52 years), and 112 control subjects having a similar age range of 18-63 years (mean+/-SD of 36.64+/-14.65 years) were enrolled in this study. A region of the p53 gene encompassing two polymorphic sites, a 16 bp duplication in intron 3 and a BstU I RFLP in exon 4, were amplified by polymerase chain reaction from Indian POAG patients and normal healthy controls. A single base change (G to C) in codon 72 alters the amino acid residue from arginine to proline and removes the polymorphic BstU I site mentioned above. The amplified DNA fragments were digested with the restriction enzyme and the digestion patterns of the fragments were used to identify the alleles for both the polymorphic sites. RESULTS: No significant association between p53 alleles and Indian POAG patients were observed by analyzing either codon 72 polymorphism (p=0.5627) or the intronic 16 bp duplication polymorphism (p=0.059). Haplotype analysis, reported to be a better predictor of association of the p53 gene with different types of cancer, was also performed and no association of any haplotype was detected with POAG (p=0.1831). CONCLUSIONS: Association between the p53 gene encoding for proline at codon 72 and POAG presumably exists in some ethnic populations but cannot be used as a predictor for the role of the gene as a common regulator of cell death of retinal ganglions leading to POAG.


Assuntos
Genes p53/genética , Glaucoma de Ângulo Aberto/genética , Polimorfismo Genético , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Idoso , Criança , Códon , Amplificação de Genes , Duplicação Gênica , Glaucoma de Ângulo Aberto/etnologia , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
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