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1.
Pacing Clin Electrophysiol ; 39(11): 1254-1260, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27550834

RESUMEN

BACKGROUND: Radiofrequency (RF) technology has improved detection of retained surgical sponges with a reported 100% sensitivity and specificity. However, the potential for interactions of the RF signals emitted by the detection system with cardiac implantable electronic devices (CIEDs) or temporary pacemakers may limit its use in those patients with these devices. This study investigated whether RF detection technology causes interference or clinically significant changes in the programmed settings of implanted pacemakers and defibrillators or temporary epicardial pacemakers. METHODS: Fifty patients who were scheduled either for CIED removal or placement of a temporary epicardial pacemaker (at the time of open heart surgery) were recruited for this study. Device settings and measurements from separate interrogations before and after scanning with the RF detection system were compared. For the temporary pacemakers, we observed for any changes in hemodynamics or signs of pacing interference. RESULTS: Twenty (40%) pacemakers, 20 (40%) implantable cardioverter defibrillators, and 10 (20%) temporary pacemakers were analyzed in this study. During scanning, no signal interference was detected in any permanent device, and there were no significant changes in programmed settings after scanning with the RF detection system. However, pacing inhibition was detected with temporary pacing systems when programmed to a synchronous mode (DDD). CONCLUSIONS: RF detection technology can be safely used to scan for retained surgical sponges in patients with permanent CIEDs and temporary pacemakers set to asynchronous mode.


Asunto(s)
Desfibriladores Implantables , Cuerpos Extraños/diagnóstico , Marcapaso Artificial , Ondas de Radio , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Europace ; 16(3): 372-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24127355

RESUMEN

AIMS: Managing an infection of the pocket of a cardiac implantable electronic device (CIED) is frequently challenging. The wound is often treated with a drain or wet-to-dry dressings that allow healing by secondary intention. Such treatment can prolong the hospital stay and can frequently result in a disfiguring scar. Negative pressure wound therapy (NPWT) has been frequently used to promote the healing of chronic or infected surgical wounds. Here we describe the first series of 28 patients in which NPWT was successfully used to treat CIED pocket infections. METHODS AND RESULTS: After removal of the CIED and debridement of the pocket, a negative pressure of 125 mmHg continuously applied to the wound through an occlusive dressing. Negative pressure wound therapy was continued for a median of 5 days (range 2-15 days) and drained an average of 260 mL sero-sanguineous fluid (range 35-970 mL). At the conclusion of NPWT, delayed primary closure of the pocket was performed with 1-0 prolene mattress sutures. The median length of stay after CIED extraction was 11.0 days (range 2-43 days). Virtually all infected pockets healed without complications and without evidence of recurrent infection over a median follow-up of 49 days (range 10-752 days). One patient developed a recurrent infection when NPWT was discontinued prematurely and a new device was implanted at the infected site. CONCLUSION: We conclude that NPWT is a safe and effective means to promote healing of infected pockets with a low incidence of recurrent infection and a satisfactory cosmetic result.


Asunto(s)
Desfibriladores Implantables/efectos adversos , Electrodos Implantados/efectos adversos , Terapia de Presión Negativa para Heridas/métodos , Marcapaso Artificial/efectos adversos , Infecciones Relacionadas con Prótesis/etiología , Infecciones Relacionadas con Prótesis/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia de Presión Negativa para Heridas/instrumentación , Apósitos Oclusivos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/terapia , Resultado del Tratamiento
3.
Diagnostics (Basel) ; 14(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38786284

RESUMEN

Many clinical studies have shown wide performance variation in tests to identify coronary artery disease (CAD). Coronary computed tomography angiography (CCTA) has been identified as an effective rule-out test but is not widely available in the USA, particularly so in rural areas. Patients in rural areas are underserved in the healthcare system as compared to urban areas, rendering it a priority population to target with highly accessible diagnostics. We previously developed a machine-learned algorithm to identify the presence of CAD (defined by functional significance) in patients with symptoms without the use of radiation or stress. The algorithm requires 215 s temporally synchronized photoplethysmographic and orthogonal voltage gradient signals acquired at rest. The purpose of the present work is to validate the performance of the algorithm in a frozen state (i.e., no retraining) in a large, blinded dataset from the IDENTIFY trial. IDENTIFY is a multicenter, selectively blinded, non-randomized, prospective, repository study to acquire signals with paired metadata from subjects with symptoms indicative of CAD within seven days prior to either left heart catheterization or CCTA. The algorithm's sensitivity and specificity were validated using a set of unseen patient signals (n = 1816). Pre-specified endpoints were chosen to demonstrate a rule-out performance comparable to CCTA. The ROC-AUC in the validation set was 0.80 (95% CI: 0.78-0.82). This performance was maintained in both male and female subgroups. At the pre-specified cut point, the sensitivity was 0.85 (95% CI: 0.82-0.88), and the specificity was 0.58 (95% CI: 0.54-0.62), passing the pre-specified endpoints. Assuming a 4% disease prevalence, the NPV was 0.99. Algorithm performance is comparable to tertiary center testing using CCTA. Selection of a suitable cut-point results in the same sensitivity and specificity performance in females as in males. Therefore, a medical device embedding this algorithm may address an unmet need for a non-invasive, front-line point-of-care test for CAD (without any radiation or stress), thus offering significant benefits to the patient, physician, and healthcare system.

4.
Dev Biol ; 371(1): 35-46, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22898305

RESUMEN

Spermatogonial stem cells divide throughout life, maintaining their own population and giving rise to differentiated gametes. The unstable regulatory protein Geminin is thought to be one of the factors that determine whether stem cells continue to divide or terminally differentiate. Geminin regulates the extent of DNA replication and is thought to maintain cells in an undifferentiated state by inhibiting various transcription factors and chromatin remodeling proteins. To examine how Geminin might regulate spermatogenesis, we developed two conditional mouse models in which the Geminin gene (Gmnn) is deleted from either spermatogonia or meiotic spermatocytes. Deleting Geminin from spermatogonia causes complete sterility in male mice. Gmnn(-/-) spermatogonia disappear during the initial wave of mitotic proliferation that occurs during the first week of life. Gmnn(-/-) spermatogonia exhibit more double-stranded DNA breaks than control cells, consistent with a defect in DNA replication. They maintain expression of genes associated with the undifferentiated state and do not prematurely express genes characteristic of more differentiated spermatogonia. In contrast, deleting Geminin from spermatocytes does not disrupt meiosis or the differentiation of spermatids into mature sperm. In females, Geminin is not required for meiosis, oocyte differentiation, or fertility after the embryonic period of mitotic proliferation has ceased. We conclude that Geminin is absolutely required for mitotic proliferation of spermatogonia but does not regulate their differentiation. Our results suggest that Geminin maintains replication fidelity during the mitotic phase of spermatogenesis, ensuring the precise duplication of genetic information for transmission to the next generation.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proliferación Celular , Fertilidad/genética , Mitosis/fisiología , Proteínas Nucleares/metabolismo , Espermatogonias/fisiología , Animales , Proteínas de Ciclo Celular/deficiencia , Proteínas de Ciclo Celular/genética , Roturas del ADN de Doble Cadena , Replicación del ADN/genética , Galactósidos , Geminina , Técnicas de Inactivación de Genes , Inmunohistoquímica , Indoles , Masculino , Ratones , Proteínas Nucleares/deficiencia , Proteínas Nucleares/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Espermatogonias/citología
6.
Catheter Cardiovasc Interv ; 79(2): 198-209, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21542113

RESUMEN

OBJECTIVES: To evaluate the cost-effectiveness of alternative approaches to revascularization for patients with three-vessel or left main coronary artery disease (CAD). BACKGROUND: Previous studies have demonstrated that, despite higher initial costs, long-term costs with bypass surgery (CABG) in multivessel CAD are similar to those for percutaneous coronary intervention (PCI). The impact of drug-eluting stents (DES) on these results is unknown. METHODS: The SYNTAX trial randomized 1,800 patients with left main or three-vessel CAD to either CABG (n = 897) or PCI using paclitaxel-eluting stents (n = 903). Resource utilization data were collected prospectively for all patients, and cumulative 1-year costs were assessed from the perspective of the U.S. healthcare system. RESULTS: Total costs for the initial hospitalization were $5,693/patient higher with CABG, whereas follow-up costs were $2,282/patient higher with PCI due mainly to more frequent revascularization procedures and higher outpatient medication costs. Total 1-year costs were thus $3,590/patient higher with CABG, while quality-adjusted life expectancy was slightly higher with PCI. Although PCI was an economically dominant strategy for the overall population, cost-effectiveness varied considerably according to angiographic complexity. For patients with high angiographic complexity (SYNTAX score > 32), total 1-year costs were similar for CABG and PCI, and the incremental cost-effectiveness ratio for CABG was $43,486 per quality-adjusted life-year gained. CONCLUSIONS: Among patients with three-vessel or left main CAD, PCI is an economically attractive strategy over the first year for patients with low and moderate angiographic complexity, while CABG is favored among patients with high angiographic complexity.


Asunto(s)
Angioplastia Coronaria con Balón/economía , Puente de Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/economía , Stents Liberadores de Fármacos/economía , Costos de la Atención en Salud , Anciano , Angiografía Coronaria , Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Análisis Costo-Beneficio , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
7.
Proc Natl Acad Sci U S A ; 106(27): 11154-9, 2009 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-19549856

RESUMEN

WT1, a critical regulator of kidney development, is a tumor suppressor for nephroblastoma but in some contexts functions as an oncogene. A limited number of direct transcriptional targets of WT1 have been identified to explain its complex roles in tumorigenesis and organogenesis. In this study we performed genome-wide screening for direct WT1 targets, using a combination of ChIP-ChIP and expression arrays. Promoter regions bound by WT1 were highly G-rich and resembled the sites for a number of other widely expressed transcription factors such as SP1, MAZ, and ZNF219. Genes directly regulated by WT1 were implicated in MAPK signaling, axon guidance, and Wnt pathways. Among directly bound and regulated genes by WT1, nine were identified in the Wnt signaling pathway, suggesting that WT1 modulates a subset of Wnt components and responsive genes by direct binding. To prove the biological importance of the interplay between WT1 and Wnt signaling, we showed that WT1 blocked the ability of Wnt8 to induce a secondary body axis during Xenopus embryonic development. WT1 inhibited TCF-mediated transcription activated by Wnt ligand, wild type and mutant, stabilized beta-catenin by preventing TCF4 loading onto a promoter. This was neither due to direct binding of WT1 to the TCF binding site nor to interaction between WT1 and TCF4, but by competition of WT1 and TCF4 for CBP. WT1 interference with Wnt signaling represents an important mode of its action relevant to the suppression of tumor growth and guidance of development.


Asunto(s)
Pruebas Genéticas , Genoma/genética , Transducción de Señal/genética , Proteínas WT1/metabolismo , Proteínas Wnt/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Proteína de Unión a CREB/metabolismo , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , ADN/metabolismo , Embrión no Mamífero/metabolismo , Desarrollo Embrionario , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas/genética , Unión Proteica , Factores de Transcripción TCF/metabolismo , Transcripción Genética , Xenopus/embriología
8.
JACC Case Rep ; 4(22): 1515-1521, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36444176

RESUMEN

Pericardial decompression syndrome (PDS) is a potentially fatal disorder of left ventricular function that sometimes occurs after drainage of a pericardial effusion for cardiac tamponade. Patients at risk for PDS are difficult to identify. Here, we report 2 cases where PDS developed after drainage of effusions that had been present for years, suggesting that patients with chronic effusions are at higher risk for PDS. (Level of Difficulty: Advanced.).

9.
Front Cardiovasc Med ; 9: 956147, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36119746

RESUMEN

Introduction: Multiple trials have demonstrated broad performance ranges for tests attempting to detect coronary artery disease. The most common test, SPECT, requires capital-intensive equipment, the use of radionuclides, induction of stress, and time off work and/or travel. Presented here are the development and clinical validation of an office-based machine learned algorithm to identify functionally significant coronary artery disease without radiation, expensive equipment or induced patient stress. Materials and methods: The IDENTIFY trial (NCT03864081) is a prospective, multicenter, non-randomized, selectively blinded, repository study to collect acquired signals paired with subject meta-data, including outcomes, from subjects with symptoms of coronary artery disease. Time synchronized orthogonal voltage gradient and photoplethysmographic signals were collected for 230 seconds from recumbent subjects at rest within seven days of either left heart catheterization or coronary computed tomography angiography. Following machine learning on a proportion of these data (N = 2,522), a final algorithm was selected, along with a pre-specified cut point on the receiver operating characteristic curve for clinical validation. An unseen set of subject signals (N = 965) was used to validate the algorithm. Results: At the pre-specified cut point, the sensitivity for detecting functionally significant coronary artery disease was 0.73 (95% CI: 0.68-0.78), and the specificity was 0.68 (0.62-0.74). There exists a point on the receiver operating characteristic curve at which the negative predictive value is the same as coronary computed tomographic angiography, 0.99, assuming a disease incidence of 0.04, yielding sensitivity of 0.89 and specificity of 0.42. Selecting a point at which the positive predictive value is maximized, 0.12, yields sensitivity of 0.39 and specificity of 0.88. Conclusion: The performance of the machine learned algorithm presented here is comparable to common tertiary center testing for coronary artery disease. Employing multiple cut points on the receiver operating characteristic curve can yield the negative predictive value of coronary computed tomographic angiography and a positive predictive value approaching that of myocardial perfusion imaging. As such, a system employing this algorithm may address the need for a non-invasive, no radiation, no stress, front line test, and hence offer significant advantages to the patient, their physician, and healthcare system.

10.
PLoS One ; 17(11): e0277300, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36378672

RESUMEN

BACKGROUND: Phase space is a mechanical systems approach and large-scale data representation of an object in 3-dimensional space. Whether such techniques can be applied to predict left ventricular pressures non-invasively and at the point-of-care is unknown. OBJECTIVE: This study prospectively validated a phase space machine-learned approach based on a novel electro-mechanical pulse wave method of data collection through orthogonal voltage gradient (OVG) and photoplethysmography (PPG) for the prediction of elevated left ventricular end diastolic pressure (LVEDP). METHODS: Consecutive outpatients across 15 US-based healthcare centers with symptoms suggestive of coronary artery disease were enrolled at the time of elective cardiac catheterization and underwent OVG and PPG data acquisition immediately prior to angiography with signals paired with LVEDP (IDENTIFY; NCT #03864081). The primary objective was to validate a ML algorithm for prediction of elevated LVEDP using a definition of ≥25 mmHg (study cohort) and normal LVEDP ≤ 12 mmHg (control cohort), using AUC as the measure of diagnostic accuracy. Secondary objectives included performance of the ML predictor in a propensity matched cohort (age and gender) and performance for an elevated LVEDP across a spectrum of comparative LVEDP (<12 through 24 at 1 mmHg increments). Features were extracted from the OVG and PPG datasets and were analyzed using machine-learning approaches. RESULTS: The study cohort consisted of 684 subjects stratified into three LVEDP categories, ≤12 mmHg (N = 258), LVEDP 13-24 mmHg (N = 347), and LVEDP ≥25 mmHg (N = 79). Testing of the ML predictor demonstrated an AUC of 0.81 (95% CI 0.76-0.86) for the prediction of an elevated LVEDP with a sensitivity of 82% and specificity of 68%, respectively. Among a propensity matched cohort (N = 79) the ML predictor demonstrated a similar result AUC 0.79 (95% CI: 0.72-0.8). Using a constant definition of elevated LVEDP and varying the lower threshold across LVEDP the ML predictor demonstrated and AUC ranging from 0.79-0.82. CONCLUSION: The phase space ML analysis provides a robust prediction for an elevated LVEDP at the point-of-care. These data suggest a potential role for an OVG and PPG derived electro-mechanical pulse wave strategy to determine if LVEDP is elevated in patients with symptoms suggestive of cardiac disease.


Asunto(s)
Disfunción Ventricular Izquierda , Humanos , Disfunción Ventricular Izquierda/diagnóstico , Presión Sanguínea , Sistemas de Atención de Punto , Análisis de la Onda del Pulso , Aprendizaje Automático , Función Ventricular Izquierda , Presión Ventricular , Volumen Sistólico
11.
Dev Dyn ; 238(10): 2614-21, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19705441

RESUMEN

The cell nucleus must be inactivated or destroyed in order to generate feeder layers for cultured cells or to prepare recipient egg cells for nuclear transfer. Existing enucleation techniques are either cumbersome or employ toxic chemicals. Here we report a new method to enucleate cells by treatment with a psoralen and long-wave ultraviolet light. The technique is >90% efficient and causes little cytoplasmic damage to the treated cell. We have used psoralen treatment to enucleate a wide variety of cells, including eggs, sperm, HeLa cells, and fibroblasts. Colonies of human embryonic stem cells (hESCs) and human keratinocyte precursors grown on psoralen-treated feeders are indistinguishable from those grown on gamma-irradiated or mitomycin C-treated cells. Psoralen enucleation provides a rapid, simple, and non-toxic method to generate feeder cells. The technique is also useful for nuclear transfer studies in species with large eggs whose cleavage divisions are not regulated by cell-cycle checkpoints.


Asunto(s)
Núcleo Celular , Furocumarinas/farmacología , Fármacos Fotosensibilizantes/farmacología , Animales , Técnicas de Cultivo de Célula , Núcleo Celular/efectos de los fármacos , Núcleo Celular/efectos de la radiación , Células Cultivadas , Femenino , Células HeLa , Humanos , Cariotipificación , Masculino , Oocitos/citología , Oocitos/efectos de los fármacos , Oocitos/efectos de la radiación , Espermatozoides/citología , Espermatozoides/efectos de los fármacos , Espermatozoides/efectos de la radiación , Rayos Ultravioleta , Xenopus laevis/embriología , Xenopus laevis/crecimiento & desarrollo
13.
Eur Heart J ; 29(13): 1625-34, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18556716

RESUMEN

AIMS: This study sought to investigate the 2-year outcomes of patients treated with the paclitaxel-eluting TAXUS((R)) stent (PES) or vascular brachytherapy (VBT), the previous 'gold standard therapy', for bare metal stent in-stent restenosis (ISR). METHODS AND RESULTS: In the TAXUS V-ISR trial, 396 patients with bare metal stent ISR referred for percutaneous coronary intervention were prospectively randomized to either PES or beta source VBT. The present analysis reports 24-month clinical outcomes from that study. Between 9 and 24 months, ischaemia-driven target lesion revascularization tended to be required less frequently with assignment to PES compared to VBT (5.3 vs. 10.3%, P = .07). As a result, ischaemia-driven target lesion revascularization at 24 months was significantly reduced with PES compared with VBT (10.1 vs. 21.6%, P = 0.003), as was ischaemia-driven target vessel revascularization (18.1 vs. 27.5%, P = .03). There were no significant differences between the two groups with regard to death, myocardial infarction, or target vessel thrombosis either between 12 and 24 months, or cumulative to 24 months. CONCLUSION: Freedom from clinical restenosis at 2 years is significantly enhanced after PES placement compared with VBT for bare metal stent ISR, with similar rates of death, myocardial infarction, and target vessel thrombosis.


Asunto(s)
Braquiterapia , Reestenosis Coronaria/terapia , Stents Liberadores de Fármacos , Paclitaxel/administración & dosificación , Moduladores de Tubulina/administración & dosificación , Anciano , Reestenosis Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Factores de Riesgo , Resultado del Tratamiento
14.
Mol Carcinog ; 47(11): 835-44, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18404646

RESUMEN

Pancreatic adeniocarcinoma is among the deadliest of human cancers. Apigenin, an antitumor flavonoid, inhibits pancreatic cancer cell proliferation in vitro. Geminin is a recently identified novel protein that plays a critical role in preventing abnormal DNA replication by binding to and inhibiting the essential replication factor Cdt1. Microarray analysis identified geminin to be downregulated in pancreatic cancer cells treated with apigenin. Therefore, we investigated the effects of apigenin on geminin expression and other proteins involved in replication (Cdc6, Cdt1, and MCM7) in pancreatic cancer cell lines CD18 and S2013. Real time RT-PCR and western blotting analysis showed that geminin expression is downregulated by apigenin at both mRNA and protein levels. Furthermore, treatment of cells with proteosome inhibitor MG132 reversed the downregulation of geminin by apigenin, supporting our hypothesis that the degradation pathway is another mechanism by which apigenin affects geminin expression. Apigenin treatment also resulted in downregulation of Cdc6 at both mRNA and protein levels. However, Cdt1 and MCM7 expression was not affected in apigenin-treated cells. The effect of apigenin treatment on geminin promoter activity was measured by transient transfection of Hela cells with a reporter gene, demonstrating that apigenin inhibited geminin promoter activity. Geminin expression was also evaluated in human pancreatic tissue (n = 15) by immunohistochemistry and showed that geminin is overexpressed in human pancreatic cancer compared to normal adjacent pancreatic tissue. In conclusion, our studies demonstrated that geminin is overexpressed in human pancreatic cancer and downregulated by apigenin which may contribute to the antitumor effect of this natural flavonoid.


Asunto(s)
Apigenina/farmacología , Productos Biológicos/farmacología , Proteínas de Ciclo Celular/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Pancreáticas/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Geminina , Humanos , Leupeptinas/farmacología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Regiones Promotoras Genéticas/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma , ARN Mensajero/genética
15.
Dent Today ; 27(12): 108, 110-1, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19133641

RESUMEN

This patient's treatment involved a complex diagnostic challenge, as well as a challenging clinical sequence due to the utilization of immediate implant placement and restoration after extraction along with immediate prosthodontic restoration with sinus elevation with bone grafting. The inability to have diagnostic patient wax try-ins required a detailed and exacting diagnostic work-up which included significant laboratory diagnostic wax-ups. The utilization of the ACP Parameters of Care for Partial Edentulism for a PDI Class IV patient provided a framework in which care could be planned and executed with confidence. The availability of various reconstructive materials and techniques to create a seamless restorative result is essential to the success of this type of advanced treatment.


Asunto(s)
Estética Dental , Rehabilitación Bucal/métodos , Aumento de la Cresta Alveolar , Coronas , Implantes Dentales , Prótesis Dental de Soporte Implantado , Dentadura Completa Inmediata , Dentadura Completa Inferior , Humanos , Masculino , Maloclusión/terapia , Masticación/fisiología , Persona de Mediana Edad , Planificación de Atención al Paciente , Abrasión de los Dientes/terapia , Enfermedades Dentales/terapia , Erupción Dental , Dimensión Vertical
16.
Mol Biol Cell ; 13(10): 3662-71, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12388764

RESUMEN

Geminin is an unstable inhibitor of DNA replication that gets destroyed at the metaphase/anaphase transition. The biological function of geminin has been difficult to determine because it is not homologous to a characterized protein and has pleiotropic effects when overexpressed. Geminin is thought to prevent a second round of initiation during S or G2 phase. In some assays, geminin induces uncommitted embryonic cells to differentiate as neurons. In this study, geminin was eliminated from developing Xenopus embryos by using antisense techniques. Geminin-deficient embryos show a novel and unusual phenotype: they complete the early cleavage divisions normally but arrest in G2 phase immediately after the midblastula transition. The arrest requires Chk1, the effector kinase of the DNA replication/DNA damage checkpoint pathway. The results indicate that geminin has an essential function and that loss of this function prevents entry into mitosis by a Chk1-dependent mechanism. Geminin may be required to maintain the structural integrity of the genome or it may directly down-regulate Chk1 activity. The data also show that during the embryonic cell cycles, rereplication is almost entirely prevented by geminin-independent mechanisms.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Embrión no Mamífero/fisiología , Fase G2/fisiología , Proteínas Quinasas/metabolismo , Xenopus laevis/fisiología , Animales , Proteína Quinasa CDC2/genética , Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Replicación del ADN/fisiología , Embrión no Mamífero/anatomía & histología , Geminina , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/metabolismo , Fenotipo , ARN/genética , ARN/metabolismo , Proteínas de Xenopus , Fosfatasas cdc25/genética , Fosfatasas cdc25/metabolismo
17.
Stem Cell Reports ; 8(4): 1086-1100, 2017 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-28410642

RESUMEN

Large-scale collections of induced pluripotent stem cells (iPSCs) could serve as powerful model systems for examining how genetic variation affects biology and disease. Here we describe the iPSCORE resource: a collection of systematically derived and characterized iPSC lines from 222 ethnically diverse individuals that allows for both familial and association-based genetic studies. iPSCORE lines are pluripotent with high genomic integrity (no or low numbers of somatic copy-number variants) as determined using high-throughput RNA-sequencing and genotyping arrays, respectively. Using iPSCs from a family of individuals, we show that iPSC-derived cardiomyocytes demonstrate gene expression patterns that cluster by genetic background, and can be used to examine variants associated with physiological and disease phenotypes. The iPSCORE collection contains representative individuals for risk and non-risk alleles for 95% of SNPs associated with human phenotypes through genome-wide association studies. Our study demonstrates the utility of iPSCORE for examining how genetic variants influence molecular and physiological traits in iPSCs and derived cell lines.


Asunto(s)
Arritmias Cardíacas/genética , Bases de Datos Factuales , Estudios de Asociación Genética , Variación Genética , Células Madre Pluripotentes Inducidas/metabolismo , Miocitos Cardíacos/metabolismo , Arritmias Cardíacas/etnología , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatología , Diferenciación Celular , Línea Celular , Reprogramación Celular/genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Células Madre Pluripotentes Inducidas/citología , Familia de Multigenes , Miocitos Cardíacos/citología , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Polimorfismo de Nucleótido Simple , Grupos Raciales
18.
JAMA ; 295(11): 1253-63, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16531618

RESUMEN

CONTEXT: Restenosis within bare-metal stents is often treated with repeat percutaneous coronary intervention, although subsequent recurrence rates are high, with vascular brachytherapy (VBT) affording the best results. The effectiveness of drug-eluting stents in this setting has not been established. OBJECTIVE: To investigate the safety and efficacy of the polymer-based, slow-release paclitaxel-eluting stent in patients with restenotic lesions after prior stent implantation in native coronary arteries. DESIGN, SETTING, AND PATIENTS: Prospective, multicenter, randomized trial conducted between June 6, 2003, and July 16, 2004, at 37 North American academic and community-based institutions in 396 patients with in-stent restenosis of a previously implanted bare-metal coronary stent (vessel diameter, 2.5-3.75 mm; lesion length, < or =46 mm). INTERVENTIONS: Patients were randomly assigned to undergo angioplasty followed by VBT with a beta source (n = 201) or paclitaxel-eluting stent implantation (n = 195). Clinical and angiographic follow-up at 9 months was scheduled in all patients. MAIN OUTCOME MEASURE: Ischemia-driven target vessel revascularization at 9 months. RESULTS: Diabetes mellitus was present in 139 patients (35.1%). Median reference vessel diameter was 2.65 mm and median lesion length was 15.3 mm. In the VBT group, new stents were implanted in 22 patients (10.9%) and in the paclitaxel-eluting stent group, multiple stents were required in 57 patients (29.2%), with median stent length of 24 mm. Follow-up at 9 months was complete in 194 patients in the VBT group and 191 patients in the paclitaxel-eluting stent group (96.5% and 97.9%, respectively). For VBT and paclitaxel-eluting stents, respectively, the number of events and 9-month rates for ischemic target lesion revascularization were 27 (13.9%) vs 12 (6.3%) (relative risk [RR], 0.45; 95% confidence interval [CI], 0.24-0.86; P = .01); for ischemic target vessel revascularization, 34 (17.5%) vs 20 (10.5%) (RR, 0.60; 95% CI, 0.36-1.00; P = .046); and for overall major adverse cardiac events, 39 (20.1%) vs 22 (11.5%) (RR, 0.57; 95% CI, 0.35-0.93; P = .02), with similar rates of cardiac death or myocardial infarction (10 [5.2%] vs 7 [3.7%]; RR, 0.71; 95% CI, 0.28-1.83; P = .48) and target vessel thrombosis (5 [2.6%] vs 3 [1.6%]; RR, 0.61; 95% CI, 0.15-2.50; P = .72). Angiographic restenosis at 9 months was 31.2% (53 of 170 patients) with VBT and 14.5% (25 of 172 patients) with paclitaxel-eluting stents (RR, 0.47; 95% CI, 0.30-0.71; P<.001). CONCLUSION: Treatment of bare-metal in-stent restenotic lesions with paclitaxel-eluting stents rather than angioplasty followed by VBT reduces clinical and angiographic restenosis at 9 months and improves event-free survival. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00287573.


Asunto(s)
Braquiterapia , Reestenosis Coronaria/terapia , Paclitaxel/administración & dosificación , Stents , Anciano , Angioplastia Coronaria con Balón , Angiografía Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
19.
J Am Coll Cardiol ; 40(12): 2125-34, 2002 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-12505224

RESUMEN

OBJECTIVES: The purpose of this study was to assess the efficacy and safety of ezetimibe administered with simvastatin in patients with primary hypercholesterolemia. BACKGROUND: Despite the availability of statins, many patients do not achieve lipid targets. Combination therapy with lipid-lowering agents that act via a complementary pathway may allow additional patients to achieve recommended cholesterol goals. METHODS: After dietary stabilization, a 2- to 12-week washout period, and a 4-week, single-blind, placebo lead-in period, patients with baseline low-density lipoprotein cholesterol (LDL-C) > or =145 mg/dl to < or =250 mg/dl and triglycerides (TG) < or =350 mg/dl were randomized to one of the following 10 groups administered daily for 12 consecutive weeks: ezetimibe 10 mg; simvastatin 10, 20, 40, or 80 mg; ezetimibe 10 mg plus simvastatin 10, 20, 40, or 80 mg; or placebo. The primary efficacy variable was percentage reduction from baseline to end point in direct LDL-C for the pooled ezetimibe plus simvastatin groups versus pooled simvastatin groups. RESULTS: Ezetimibe plus simvastatin significantly improved LDL-C (p < 0.01), high-density lipoprotein cholesterol (HDL-C) (p = 0.03), and TG (p < 0.01) compared with simvastatin alone. Ezetimibe plus simvastatin (pooled doses) provided an incremental 13.8% LDL-C reduction, 2.4% HDL-C increase, and 7.5% TG reduction compared with pooled simvastatin alone. Coadministration of ezetimibe and simvastatin provided LDL-C reductions of 44% to 57%, TG reductions of 20% to 28%, and HDL-C increases of 8% to 11%, depending on the simvastatin dose. Ezetimibe 10 mg plus simvastatin 10 mg and simvastatin 80 mg alone each provided a 44% LDL-C reduction. The coadministration of ezetimibe with simvastatin was well tolerated, with a safety profile similar to those of simvastatin and of placebo. CONCLUSIONS: When coadministered with simvastatin, ezetimibe provided significant incremental reductions in LDL-C and TG, as well as increases in HDL-C. Coadministration of ezetimibe with simvastatin was well tolerated and comparable to statin alone.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Azetidinas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Simvastatina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Quimioterapia Combinada , Ezetimiba , Femenino , Humanos , Hipercolesterolemia/sangre , Lípidos/sangre , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
20.
Am J Cardiol ; 95(6): 709-15, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15757595

RESUMEN

The effect of obesity on repeat coronary revascularization and restenosis in patients who undergo stent implantation has not been reported. We therefore examined the database from the multicenter randomized TAXUS-IV trial to determine the effect of body mass index (BMI) on outcomes after bare-metal and drug-eluting stent implantation. In TAXUS-IV, patients were randomized to receive a slow-release, polymer-based, paclitaxel-eluting stent or a bare-metal stent. Outcomes were stratified by baseline BMI. Of the 1,307 randomized patients who had documented BMI, 233 (17.8%) had normal weight (BMI <25 kg/m2), 531 (40.6%) were overweight (BMI < or =25 to 30 kg/m2), and 543 (41.5%) were obese (BMI > or =30 kg/m2). Patients who had been assigned to receive bare-metal stents and were overweight and obese compared with those who had normal weight had higher rates of 9-month binary restenosis (29.2% and 30.5% vs 9.3%, respectively; p = 0.01) and 1-year major adverse cardiac events (20.8% and 23.2% vs 11.1%, respectively; p = 0.02), whereas rates of these events did not differ significantly among those who received a paclitaxel-eluting stent (7.6% and 9.3% vs 4.9%, respectively for binary restenosis; p = 0.65; 11.3% and 10.4% vs 10.1%, respectively; p = 0.82 for major adverse cardiac events). By multivariate analysis, BMI > or =30.0 kg/m2 independently predicted binary restenosis (hazard ratio 4.26, p = 0.005), 1-year target vessel revascularization (hazard ratio 1.95, p = 0.04), and major adverse cardiac events (hazard ratio 1.95, p = 0.004) in patients who received bare-metal stents but not paclitaxel-eluting stents. In conclusion, obesity is an important risk factor for clinical and angiographic restenosis and for composite major adverse cardiac events in patients who receive bare-metal stents. Paclitaxel-eluting stents attenuate the increased risk associated with obesity, such that the intermediate-term prognosis after percutaneous coronary intervention is independent of weight.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Enfermedad Coronaria/terapia , Reestenosis Coronaria/mortalidad , Metales , Obesidad/complicaciones , Paclitaxel/administración & dosificación , Polímeros , Stents , Anciano , Angina de Pecho/diagnóstico por imagen , Angina de Pecho/mortalidad , Angina de Pecho/terapia , Angina Inestable/diagnóstico por imagen , Angina Inestable/mortalidad , Angina Inestable/terapia , Índice de Masa Corporal , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/mortalidad , Reestenosis Coronaria/diagnóstico por imagen , Preparaciones de Acción Retardada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/mortalidad , Isquemia Miocárdica/terapia , Obesidad/epidemiología , Obesidad/mortalidad , Modelos de Riesgos Proporcionales , Factores de Riesgo
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