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1.
J Integr Bioinform ; 18(3)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34098590

RESUMO

People who are engineering biological organisms often find it useful to communicate in diagrams, both about the structure of the nucleic acid sequences that they are engineering and about the functional relationships between sequence features and other molecular species. Some typical practices and conventions have begun to emerge for such diagrams. The Synthetic Biology Open Language Visual (SBOL Visual) has been developed as a standard for organizing and systematizing such conventions in order to produce a coherent language for expressing the structure and function of genetic designs. This document details version 2.3 of SBOL Visual, which builds on the prior SBOL Visual 2.2 in several ways. First, the specification now includes higher-level "interactions with interactions," such as an inducer molecule stimulating a repression interaction. Second, binding with a nucleic acid backbone can be shown by overlapping glyphs, as with other molecular complexes. Finally, a new "unspecified interaction" glyph is added for visualizing interactions whose nature is unknown, the "insulator" glyph is deprecated in favor of a new "inert DNA spacer" glyph, and the polypeptide region glyph is recommended for showing 2A sequences.


Assuntos
Linguagens de Programação , Biologia Sintética , Humanos , Idioma
2.
J Integr Bioinform ; 17(2-3)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32543457

RESUMO

People who are engineering biological organisms often find it useful to communicate in diagrams, both about the structure of the nucleic acid sequences that they are engineering and about the functional relationships between sequence features and other molecular species. Some typical practices and conventions have begun to emerge for such diagrams. The Synthetic Biology Open Language Visual (SBOL Visual) has been developed as a standard for organizing and systematizing such conventions in order to produce a coherent language for expressing the structure and function of genetic designs. This document details version 2.2 of SBOL Visual, which builds on the prior SBOL Visual 2.1 in several ways. First, the grounding of molecular species glyphs is changed from BioPAX to SBO, aligning with the use of SBO terms for interaction glyphs. Second, new glyphs are added for proteins, introns, and polypeptide regions (e. g., protein domains), the prior recommended macromolecule glyph is deprecated in favor of its alternative, and small polygons are introduced as alternative glyphs for simple chemicals.


Assuntos
Linguagens de Programação , Biologia Sintética , Humanos , Idioma
3.
J Am Coll Cardiol ; 66(12): 1378-91, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26383726

RESUMO

Cardiovascular morbidity and mortality as a result of inhaled tobacco products continues to be a global healthcare crisis, particularly in low- and middle-income nations lacking the infrastructure to develop and implement effective public health policies limiting tobacco use. Following initiation of public awareness campaigns 50 years ago in the United States, considerable success has been achieved in reducing the prevalence of cigarette smoking and exposure to secondhand smoke. However, there has been a slowing of cessation rates in the United States during recent years, possibly caused by high residual addiction or fatigue from cessation messaging. Furthermore, tobacco products have continued to evolve faster than the scientific understanding of their biological effects. This review considers selected updates on the genetics and epigenetics of smoking behavior and associated cardiovascular risk, mechanisms of atherogenesis and thrombosis, clinical effects of smoking and benefits of cessation, and potential impact of electronic cigarettes on cardiovascular health.


Assuntos
Doenças Cardiovasculares/etiologia , Sistemas Eletrônicos de Liberação de Nicotina/efeitos adversos , Fumar/efeitos adversos , Epigênese Genética , Humanos , Fumar/legislação & jurisprudência , Abandono do Hábito de Fumar
4.
Cytotherapy ; 12(1): 67-78, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19878081

RESUMO

BACKGROUND AIMS: Current clinical trials utilize non-selected bone marrow (BM) mononuclear cells (MNC) to augment vasculo genesis within ischemic vascular beds. Recent reports have identified a diminished number and function of hemat-opoietic stem cells (HSC) from aged and diseased patients. Umbilical cord blood (UCB) provides a potential robust allo-geneic source of HSC for therapeutic vasculogenesis. METHODS: MNC and magnetically isolated CD133(+) cells were assessed for viability (trypan blue) and surface phenotype (flow cytometry). To test in vivo functionality of the cells, NOD/SCID mice underwent ligation of the right femoral artery followed immediately by cell injection. Blood flow recovery, necrosis, BM engraftment of human cells and histologic capillary density were determined. Cells were tested for potential mechanisms mediating the in vivo effects, including migration, cytokine secretion and angiogenic augmentation (Matrigel assays). RESULTS: Surface expression analysis showed CD31 (PECAM) expression was greatly increased in UCB CD133(+) cells compared with BM MNC. At 28 days, perfusion ratios were highest in animals receiving UCB CD133(+) cells, while animals receiving BM CD133(+) cells and BM MNC demonstrated perfusion ratios statistically higher than in animals treated with cytokine media alone. Animals receiving CD133(+) cells showed a statistically higher capillary density, reduced severe digit necrosis and increased engraftment in the BM than animals treated with unselected BM MNC. In vitro studies showed equivalent migration to stromal-derived factor-1 (SDF-1), increased production of tumor necrosis factor alpha (TNF-alpha) and increased branch points with the co-incubation of CD133(+) cells with human umbilical vein endothelial cells (HUVEC) in the Matrigel angiogenesis assay. CONCLUSIONS: Taken together, UCB CD133(+) cells exhibit robust vasculogenic functionality compared with BM MNC in response to ischemia.


Assuntos
Antígenos CD/metabolismo , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Sangue Fetal/fisiologia , Glicoproteínas/metabolismo , Neovascularização Fisiológica/fisiologia , Peptídeos/metabolismo , Células-Tronco/fisiologia , Antígeno AC133 , Adulto , Animais , Antígenos CD/análise , Capilares/citologia , Capilares/fisiologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas , Quimiocina CXCL12/farmacologia , Feminino , Artéria Femoral/lesões , Artéria Femoral/cirurgia , Sangue Fetal/citologia , Glicoproteínas/análise , Membro Posterior/irrigação sanguínea , Membro Posterior/cirurgia , Humanos , Separação Imunomagnética/métodos , Recém-Nascido , Isquemia/fisiopatologia , Isquemia/terapia , Camundongos , Camundongos SCID , Peptídeos/análise , Recuperação de Função Fisiológica/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Células-Tronco/citologia , Transplante Homólogo/métodos , Resultado do Tratamento
5.
Clin Cardiol ; 32(12): E80-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20014213

RESUMO

Myocardial stunning, known as stress cardiomyopathy, broken-heart syndrome, transient left ventricular apical ballooning, and Takotsubo cardiomyopathy, has been reported after many extracardiac stressors, but not following chemotherapy. We report 2 cases with characteristic electrocardiographic and echocardiographic features following combined modality therapy with combretastatin, a vascular-disrupting agent being studied for treatment of anaplastic thyroid cancer. In 1 patient, an ECG performed per protocol 18 hours after drug initiation showed deep, symmetric T-wave inversions in limb leads I and aVL and precordial leads V(2) through V(6). Echocardiography showed mildly reduced overall left ventricular systolic function with akinesis of the entire apex. The patient had mild elevations of troponin I. Coronary angiography revealed no epicardial coronary artery disease. The electrocardiographic and echocardiographic abnormalities resolved after several weeks. The patient remains stable from a cardiovascular standpoint and has not had a recurrence during follow-up. An electrocardiogram performed per protocol in a second patient showed deep, symmetric T-wave inversions throughout the precordial leads and a prolonged QT interval. Echocardiography showed mildly reduced left ventricular function with hypokinesis of the apical-septal wall. Acute coronary syndrome was ruled out, and both the electrocardiographic and echocardiographic changes resolved at follow-up. Although the patient remained pain-free without recurrence of anginal symptoms during long-term follow-up, the patient developed progressive malignancy and died.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bibenzilas/efeitos adversos , Miocárdio Atordoado/induzido quimicamente , Miocárdio Atordoado/diagnóstico , Idoso , Bibenzilas/administração & dosagem , Carcinoma/tratamento farmacológico , Diagnóstico por Imagem , Eletrocardiografia , Feminino , Humanos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Troponina I/sangue
6.
Nat Clin Pract Oncol ; 3(12): 682-92, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17139319

RESUMO

Vascular disrupting agents (VDAs), or endothelial disrupting agents, attempt to exploit the vascular endothelium that supplies rapidly dividing neoplasms. Unlike antiangiogenesis agents (e.g. the monoclonal antibody bevacizumab; and tyrosine kinase inhibitors sorafenib and sunitinib) that disrupt endothelial cell survival mechanisms and the development of a new tumor blood supply, VDAs are designed to disrupt the already established abnormal vasculature that supports tumors, by targeting their dysmorphic endothelial cells. Tumor vascular endothelium is characterized by its increased permeability, abnormal morphology, disorganized vascular networks, and variable density. VDAs induce rapid shutdown of tumor blood supply, causing subsequent tumor death from hypoxia and nutrient deprivation. The safety profile of this class of compounds is more indicative of agents that are indeed 'vascularly' active. For example, VDAs can cause: acute coronary and other thrombophlebitic syndromes; alterations in blood pressure, heart rate, and ventricular conduction; transient flush and hot flashes; neuropathy; and tumor pain. Despite these cardiovascular concerns some patients have benefited from VDAs in early clinical trials. Further drug development of VDAs must include the combination of these agents with other novel biological agents, cytotoxic chemotherapy, and radiotherapy. Close monitoring of patients receiving VDAs for any cardiovascular toxicity is imperative.


Assuntos
Inibidores da Angiogênese/farmacologia , Sistemas de Liberação de Medicamentos , Neovascularização Patológica , Inibidores da Angiogênese/farmacocinética , Endotélio Vascular/efeitos dos fármacos , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico
7.
J Invasive Cardiol ; 18(5): 212-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16670448

RESUMO

BACKGROUND: Intracoronary mononuclear cell therapy may produce angiogenesis in chronic myocardial ischemia. Potential complications include periprocedural infarction secondary to: reduced coronary blood flow; hyperviscosity from the cell preparation; or microvascular dysfunction. To date, no studies to evaluate these potential complications have been reported. The objective of this report was to study the safety and feasibility of intracoronary injections of autologous bone marrow mononuclear cells in a porcine chronic myocardial ischemia model. METHODS: Domestic pigs (n = 5) underwent ameroid cuff placement of the left circumflex artery. Bone marrow-derived mononuclear cells [15 x 10(6) cells] labeled with CM dioctadecyl tetramethylindocarbocyanine were given by intracoronary injection. Animals were sacrificed, and hearts and vital organs were inspected grossly and by histopathology, and bone marrow underwent immunofluorescence microscopy. RESULTS: Troponin I levels, gross inspection and histopathology did not reveal evidence of myocardial infarction. Labeled cells were observed in perivascular structures in myocardium at the injection site in all animals and in the spleen from one animal. Bone marrow aspirates indicated labeled cells. CONCLUSIONS: Intracoronary injection of autologous mononuclear cells in a porcine chronic myocardial ischemia model appears safe. Intracoronary injection resulted in cell localization in the perivascular areas of myocardium supplied by the injected vessel. Cell localization was observed only in the spleen in just one animal. Labeled cells were identified in bone marrow aspirates from three animals following injection, suggesting a role for bone marrow engraftment and repopulation as a possible mechanism for progenitor cell localization in myocardium.


Assuntos
Isquemia Miocárdica/cirurgia , Transplante de Células-Tronco/métodos , Animais , Medula Óssea/patologia , Doença Crônica , Vasos Coronários , Estudos de Viabilidade , Corantes Fluorescentes , Injeções Intra-Arteriais , Isquemia Miocárdica/patologia , Miocárdio/patologia , Baço/patologia , Transplante de Células-Tronco/efeitos adversos , Células-Tronco/patologia , Suínos
9.
Cardiovasc Revasc Med ; 7(1): 19-24, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16513519

RESUMO

BACKGROUND: Bone marrow mesenchymal stem cells (MSCs) can be used for myocardial repair following myocardial infarction. Increased expression of stromal cell-derived factor-1 (SDF-1) by an ischemic myocardium attracts CXCR4+ stem cells toward it. CXCR4, the receptor for SDF-1, is important in the migration, homing, and survival of hematopoietic stem cells. Although low levels of CXCR4 expression were found in minor subpopulations of cultured MSCs, most MSCs do not express CXCR4. To optimize the migration and survival of human MSCs, we expressed the CXCR4 gene in these cells using retroviral transduction. MATERIALS AND METHODS: We isolated and cultured MSCs from healthy volunteers and transduced them with a retroviral vector containing either CXCR4 and green fluorescent protein (GFP; CXCR4/GFP vector) or GFP alone (control vector). Flow cytometry confirmed successful transduction and GFP and CXCR4 expression. We used a transwell migration system to study MSC migration to SDF-1. We used Annexin V and propidium iodide stains to assess cell survival before and after the survival challenge. RESULTS: Flow cytometry showed that, on average, 83.4+/-17.7% of transduced MSCs expressed CXCR4. Compared with control MSCs, MSCs transduced with CXCR4 showed significantly more migration toward SDF-1, threefold greater at 3 h and more than fivefold greater at 6 h. Mesenchymal stem cells transduced with CXCR4 showed no significant difference in survival under normal to serum-deprived growth conditions. CONCLUSION: Mesenchymal stem cells can be efficiently transduced to express CXCR4, and transduced MSCs migrate rapidly toward SDF-1. CXCR4 expression does not render survival advantage to MSCs under serum-deprived conditions.


Assuntos
Movimento Celular/fisiologia , Quimiocinas CXC/fisiologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais/citologia , Receptores CXCR4/fisiologia , Apoptose , Adesão Celular , Moléculas de Adesão Celular/fisiologia , Quimiocina CXCL12 , Quimiotaxia/fisiologia , Citometria de Fluxo , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Células-Tronco Mesenquimais/metabolismo , Receptores CXCR4/metabolismo , Retroviridae/genética , Transdução Genética
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