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1.
J Perinatol ; 36(12): 1132-1137, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27684422

RESUMEN

OBJECTIVE: To evaluate the preparedness of pediatric residents entering accredited neonatal-perinatal medicine (NPM) fellowships in the United States. STUDY DESIGN: A multi-domain, validated survey was distributed to Program Directors (PDs) of US NPM fellowship programs. The 47-item survey explored 5 domains: professionalism, independent practice, psychomotor ability, clinical evaluation, and academia. A systematic, qualitative analysis on free-text comments was also performed. RESULTS: Sixty-one PDs completed the survey, for a response rate of 62% (61/98). For entering fellows, PDs assessed performance in professionalism positively, including 76% as communicating effectively with parents and 90% treating residents/house-staff with respect. In contrast, most PDs rated performance in psychomotor abilities negatively, including 59% and 79% as deficient in bag-and-mask ventilation and neonatal endotracheal intubation, respectively. Although 62% of PDs assessed entering fellows positively for genuine interest in academic projects, fewer than 10% responded positively that entering fellows understood research protocol design, basic statistics, or were capable of writing a cohesive manuscript well. Thematic clustering of qualitative data revealed deficits in psychomotor ability and academia/scholarship. CONCLUSIONS: On the basis of the perspective of front line educators, graduating pediatric residents are underprepared for subspecialty fellowship training in NPM. To provide the best preparation for pediatric graduates who pursue advanced training, changes to residency education to address deficiencies in these important competencies are warranted.


Asunto(s)
Competencia Clínica/normas , Becas/organización & administración , Internado y Residencia/normas , Neonatología/educación , Pediatría/educación , Investigación Biomédica/educación , Curriculum , Humanos , Encuestas y Cuestionarios , Estados Unidos
2.
J Mater Chem B ; 3(48): 9233-9241, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-32262922

RESUMEN

Nitric oxide (NO) is a biologically-active free radical involved in numerous physiological processes such as regulation of vasodilation, promotion of cell proliferation and angiogenesis, and modulation of the inflammatory and immune responses. Furthermore, NO has demonstrated the ability to mitigate the foreign body response that often results in the failure of implanted biomedical devices. Although NO has promising therapeutic value, the short physiological half-life of exogenous NO complicates its effective delivery. For this reason, the development of NO-releasing materials that permit the localized delivery of NO is an advantageous method of utilizing this molecule for biomedical applications. Herein, we report the synthesis and characterization of biodegradable NO-releasing polyesters prepared from citric acid, maleic acid, and 1,8-octanediol. NO release was achieved by incorporation of S-nitrosothiol donor groups through conjugation of cysteamine and ethyl cysteinate to the polyesters, followed by S-nitrosation with tert-butyl nitrite. The extent of NO loading and the release properties under physiological conditions (pH 7.4 PBS, 37 °C) were determined by chemiluminesence-based NO detection. The average total NO content of poly(citric-co-maleic acid-co-1,8-octanediol)-cysteamine was determined to be 0.45 ± 0.07 mol NO g-1 polymer, while the NO content for poly(citric-co-maleic acid-co-1,8-octanediol)-ethyl cysteinate was 0.16 ± 0.04 mol NO g-1 polymer. Continuous NO release under physiological conditions was observed for at least 6 days for the cysteamine analog and 4 days for the ethyl cysteinate analog. Cell viability assays and morphological studies with human dermal fibroblasts indicated an absence of toxic leachates at a cytotoxic level, and suggested that these citrate-based polyesters may be suitable for future biomedical applications.

3.
ACS Appl Mater Interfaces ; 6(15): 12307-20, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-25026120

RESUMEN

Herein, we describe the surface modification of an S-nitrosated polymer derivative via H2O plasma treatment, resulting in polymer coatings that maintained their nitric oxide (NO) releasing capabilities, but exhibited dramatic changes in surface wettability. The poly(lactic-co-glycolic acid)-based hydrophobic polymer was nitrosated to achieve a material capable of releasing the therapeutic agent NO. The NO-loaded films were subjected to low-temperature H2O plasma treatments, where the treatment power (20-50 W) and time (1-5 min) were varied. The plasma treated polymer films were superhydrophilic (water droplet spread completely in <100 ms), yet retained 90% of their initial S-nitrosothiol content. Under thermal conditions, NO release profiles were identical to controls. Under buffer soak conditions, the NO release profile was slightly lowered for the plasma-treated materials; however, they still result in physiologically relevant NO fluxes. XPS, SEM-EDS, and ATR-IR characterization suggests the plasma treatment resulted in polymer rearrangement and implantation of hydroxyl and carbonyl functional groups. Plasma treated samples maintained both hydrophilic surface properties and NO release profiles after storage at -18 °C for at least 10 days, demonstrating the surface modification and NO release capabilities are stable over time. The ability to tune polymer surface properties while maintaining bulk properties and NO release properties, and the stability of those properties under refrigerated conditions, represents a unique approach toward creating enhanced therapeutic biopolymers.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Ácido Láctico/química , Óxido Nítrico/química , Gases em Plasma/química , Ácido Poliglicólico/química , Catálisis , Cisteína/química , Hidrólisis , Microscopía Electrónica de Rastreo , Nitrosación , Espectroscopía de Fotoelectrones , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , S-Nitrosotioles , Espectrometría por Rayos X , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Agua/química , Humectabilidad
4.
Ann Biomed Eng ; 41(10): 2193-205, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23563992

RESUMEN

Nitric oxide (NO) inhibits platelet aggregation at and near the site of a vascular injury by upregulation of cyclic guanosine monophosphate, which reduces the dimerization of the integrin α(IIb)ß3. The magnitude of NO flux from the vessel wall and the NO concentration that is necessary to inhibit platelet aggregation under physiological flow conditions is unknown. In this study, a NO releasing polymer, diazeniumdiolated dibutylhexanediamine, was integrated into a microfluidic flow assay to determine the relationship between NO wall flux and collagen mediated platelet adhesion, activation and aggregation. A NO flux equal to or greater than 2.5 × 10⁻¹° mol cm⁻² min⁻¹ was found to abrogate aggregation, but not initial platelet adhesion, on collagen at 200 and 500 s⁻¹ as effectively as the α(IIb)ß3 antagonist abciximab. The dynamic range of NO fluxes found to induce measurable inhibition of platelet aggregation spanned from 0.33 × 10⁻¹° to 2.5 × 10⁻¹° mol cm⁻² min⁻¹ at 200-500 s⁻¹. These fluxes correspond to near-wall NO concentrations of 3-90 nM based on a computational model of NO transport. The model predicts that NO concentration in the platelet rich layer near the wall is kinetically limited, while NO penetration into the lumen is mass transfer limited.


Asunto(s)
Plaquetas/metabolismo , Técnicas Analíticas Microfluídicas , Modelos Biológicos , Óxido Nítrico/farmacocinética , Agregación Plaquetaria/efectos de los fármacos , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Compuestos Azo/farmacocinética , Compuestos Azo/farmacología , Transporte Biológico/fisiología , Velocidad del Flujo Sanguíneo , Plaquetas/citología , Femenino , Humanos , Masculino , Óxido Nítrico/farmacología
5.
Heredity (Edinb) ; 91(6): 584-92, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-13130306

RESUMEN

In pines, self-pollination rates can be as high as 34% yet only 5% of viable seed is a product of self-fertilization. This decline in selfed seed viability is the consequence of post-fertilization exclusion mechanisms operating via the embryo lethal system. Recent molecular marker dissection studies suggest that the embryo lethal system is composed of semilethal factors dispersed across the genome, but it is not clear whether overdominant lethal factors are rare or representative. The study objective was to determine if overdominance was rare for the embryo lethal system in conifers. Three cohorts of selfed offspring from a single Pinus taeda parent were genotyped for nuclear microsatellites. Maximum likelihood tests based on distorted segregation ratios for single markers and for interval mapping were used to infer the degree of dominance. Four hypotheses about overdominance lethal factors were tested: (1) overdominant lethal factors rarely occur within the embryo lethal system, (2) overdominant lethal factors are rarely detected because they are transient and display stage-specific expression, (3) overdominant lethal factors are rarely detected due to tight linkage with rare marker alleles and (4) dominance estimation is unbiased by gametic selection. Four out of the seven chromosomal segments were linked to an overdominant lethal factor. One of these four segments had symmetric overdominance, an effect which persisted from embryo maturity through germination. Four overdominant lethal factors were linked to common and rare marker alleles. Gametic selection was not a source of bias in dominance estimation. Overdominant or pseudo-overdominant lethal factors are a common component of the conifer embryo lethal system.


Asunto(s)
Epistasis Genética , Genes Dominantes/genética , Genoma de Planta , Endogamia , Tracheophyta/embriología , Tracheophyta/genética , Segregación Cromosómica/genética , Cartilla de ADN , Frecuencia de los Genes , Ligamiento Genético , Genotipo , Funciones de Verosimilitud , Repeticiones de Microsatélite/genética
6.
Cancer Res ; 57(21): 4838-48, 1997 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9354447

RESUMEN

The epidermal growth factor receptor (EGFR) is overexpressed in a significant percentage of carcinomas and contributes to the malignant phenotype. CP-358,774 is a directly acting inhibitor of human EGFR tyrosine kinase with an IC50 of 2 nM and reduces EGFR autophosphorylation in intact tumor cells with an IC50 of 20 nM. This inhibition is selective for EGFR tyrosine kinase relative to other tyrosine kinases we have examined, both in assays of isolated kinases and whole cells. At doses of 100 mg/kg, CP-358,774 completely prevents EGF-induced autophosphorylation of EGFR in human HN5 tumors growing as xenografts in athymic mice and of the hepatic EGFR of the treated mice. CP-358,774 inhibits the proliferation of DiFi human colon tumor cells at submicromolar concentrations in cell culture and blocks cell cycle progression at the G1 phase. This inhibitor produces a marked accumulation of retinoblastoma protein in its underphosphorylated form and accumulation of p27KIP1 in DiFi cells, which may contribute to the cell cycle block. Inhibition of the EGFR also triggers apoptosis in these cells as determined by formation of DNA fragments and other criteria. These results indicate that CP-358,774 has potential for the treatment of tumors that are dependent on the EGFR pathway for proliferation or survival.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Receptores ErbB/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Adenosina Trifosfato/metabolismo , Animales , Apoptosis/genética , Ciclo Celular/genética , División Celular/efectos de los fármacos , Fragmentación del ADN , ADN de Neoplasias/efectos de los fármacos , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Humanos , Ratones , Ratones Desnudos , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Fosforilación/efectos de los fármacos , Proteína de Retinoblastoma/metabolismo , Células Tumorales Cultivadas
7.
Chest ; 102(6): 1746-7, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1446483

RESUMEN

The increasing importance of the acquired immunodeficiency syndrome (AIDS) as a cause of large, clinically significant pericardial effusions has not been well documented. To determine the frequency and characteristics of large AIDS-associated pericardial effusions, we reviewed the records of 50 consecutive patients undergoing pericardiocentesis between 1985 and 1990; AIDS was the most common underlying illness and was present in 14 patients (28 percent). The pericardial fluid was diagnostic in three (21 percent) of the 14 cases (one bacterial, one positive for acid-fast bacilli, and one lymphoma). Of the 11 patients with nondiagnostic fluid, one underwent a pericardial biopsy which revealed granuloma consistent with mycobacterial disease, four had active pulmonary tuberculosis (TB), and two responded clinically to anti-TB therapy. Thus, in 8 (57 percent) of the 14 patients with AIDS, there was either definitive or suggestive evidence of mycobacterial disease. We conclude that AIDS is now a common underlying illness associated with large pericardial effusions and that mycobacterial disease may frequently be the etiology.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Derrame Pericárdico/complicaciones , Adulto , Taponamiento Cardíaco/complicaciones , Femenino , Humanos , Masculino , Infecciones por Mycobacterium/complicaciones , Derrame Pericárdico/microbiología , Derrame Pericárdico/patología , Tuberculosis Pulmonar/complicaciones
8.
Am J Respir Cell Mol Biol ; 3(1): 13-20, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2363934

RESUMEN

We determined whether normal human lung fibroblasts expressed cell-associated thymocyte-stimulating activity in response to recombinant interleukin-1 (rIL-1) (alpha and beta) and recombinant tumor necrosis factor (rTNF). Individually, rIL-1 and rTNF induced fibroblast expression of thymocyte-stimulating activity, with rIL-1 being significantly more potent. Importantly, combining rIL-1 and rTNF resulted in a synergistic increase in fibroblast thymocyte-stimulating activity. This synergistic interaction was dose dependent for both cytokines and was not noted when gamma-interferon was combined with rIL-1 or rTNF. In all cases, the thymocyte-stimulating activity was the result of an IL-1 alpha-like moiety whose maximal production required protein synthesis. IL-1 alpha activity could be detected after as little as 4 h, peaked after 24 h, and returned toward normal with longer periods of cytokine-fibroblast incubation. However, cytokine-stimulated fibroblasts that no longer expressed IL-1 alpha activity could be induced to re-express this activity with repeat cytokine challenge. Induction of fibroblast IL-1 alpha by IL-1 and/or TNF may be an important mechanism amplifying IL-1-mediated biologic events at sites of local inflammation.


Asunto(s)
Interleucina-1/administración & dosificación , Interleucina-1/biosíntesis , Pulmón/fisiología , Factor de Necrosis Tumoral alfa/administración & dosificación , Adhesión Celular , Células Cultivadas , Cicloheximida/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Fibroblastos , Humanos , Técnicas In Vitro , Pulmón/citología , Proteínas Recombinantes , Factores de Tiempo
9.
Proc Natl Acad Sci U S A ; 86(16): 6171-5, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2788284

RESUMEN

To understand the role fibroblasts play in mediating and amplifying the effects of inflammatory cytokines, we determined whether recombinant interleukin 1 (IL-1) and recombinant tumor necrosis factor (TNF), alone and in combination, stimulated fibroblasts to produce IL-1 beta. Recombinant IL-1 (alpha and beta) stimulated fibroblast IL-1 beta mRNA accumulation, whereas recombinant TNF did not. In addition, simultaneous stimulation with recombinant IL-1 (alpha or beta) and recombinant TNF resulted in a synergistic increase in IL-1 beta mRNA levels. However, in all cases, IL-1 beta mRNA accumulation was not associated with fibroblast production of soluble IL-1 beta protein. Lysates of unstimulated, recombinant IL-1-stimulated, and recombinant TNF-stimulated fibroblasts did not contain IL-1 beta prohormone. In contrast, IL-1 beta prohormone was detected in lysates of fibroblasts incubated simultaneously with recombinant IL-1 and recombinant TNF. These studies demonstrate that recombinant IL-1 stimulates fibroblast IL-1 beta mRNA accumulation and that recombinant IL-1 and recombinant TNF synergize to further up-regulate IL-1 beta mRNA levels. In addition, they show that IL-1 beta production by human lung fibroblasts is inhibited at a posttranscriptional level. Translational control appears to be important in recombinant IL-1-stimulated fibroblasts and posttranslational control is important in fibroblasts stimulated simultaneously with recombinant IL-1 and recombinant TNF.


Asunto(s)
Interleucina-1/genética , Procesamiento Proteico-Postraduccional/efectos de los fármacos , ARN Mensajero/genética , Factor de Necrosis Tumoral alfa/farmacología , Anticuerpos , Complejo Antígeno-Anticuerpo , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/inmunología , Humanos , Interleucina-1/biosíntesis , Interleucina-1/farmacología , Monocitos/inmunología , ARN Mensajero/efectos de los fármacos , Proteínas Recombinantes/farmacología
10.
J Relig Health ; 21(3): 245-53, 1982 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24309992

RESUMEN

It is estimated that fifteen percent of the population is in need of some kind of mental health service at any given time, thus constituting a primary health problem. The President's Commission on Mental Health (PCMH) recognized that religious institutions can help to prevent mental illness by providing support in the community. This paper presents types of programs the PCMH found that were supportive and describes the program of one church to illustrate additional ways that clergy and their congregants, working collaboratively with professionals and agencies, can contribute significantly to the prevention of mental illness.

12.
Soc Work Health Care ; 3(2): 187-98, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-366783

RESUMEN

Although the number of social workers participating in medical education is increasing, there is a need to review and evaluate their roles in such educational activities. Information is needed about how social workers participate in medical education in order to plan how to make a more effective contribution. This article describes how the role of social workers in medical education evolved, and gives examples of what social workers have done in the past and are doing today.


Asunto(s)
Educación Médica/historia , Servicio Social/historia , Docentes Médicos , Historia del Siglo XIX , Historia del Siglo XX , Medicina Social/historia , Servicio Social/educación , Estados Unidos
13.
Health Soc Work ; 1(4): 38-60, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-791772

RESUMEN

The question of professional accountability has frequently been raised with regard to the provision of health care services. Various systems, among them peer review, utilization review, and the PSRO, have accordingly been introduced to monitor the quality and the cost of health care. Social workers will have increased opportunities to participate in these review systems and, thus, to improve health care delivery.


Asunto(s)
Revisión por Pares , Organizaciones de Normalización Profesional , Servicio Social , Revisión de Utilización de Recursos , Técnicos Medios en Salud/estadística & datos numéricos , American Medical Association , Confidencialidad , Medicaid , Medicare , Organización y Administración , Servicio Social/normas , Sociedades , Estados Unidos , United States Dept. of Health and Human Services
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