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1.
Curr Oncol ; 26(6): 361-368, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31896934

RESUMEN

Background: Quitting smoking after a cancer diagnosis maximizes treatment-related effects, improves prognosis, and enhances quality of life. However, smoking cessation (sc) services are not routinely integrated into cancer care. The Princess Margaret Cancer Centre implemented a digitally-based sc program in oncology, leveraging an e-referral system (cease) to screen all new ambulatory patients, provide tailored education and advice on quitting, and facilitate referrals. Methods: We adopted the Framework for Managing eHealth Change to guide implementation of the sc program by integrating 6 key elements: governance and leadership, stakeholder engagement, communication, workflow analysis and integration, monitoring and evaluation, and training and education. Results: Incorporating elements of the Framework, we used extensive stakeholder engagement and strategic partnerships to establish a sc program with organizational and provincial accountability. Existing electronic patient-reported assessments were changed to integrate cease. Clinic audits and staff engagement allowed for analysis of workflow, ongoing monitoring and evaluation that aided in establishing a communication strategy, and development of cancer-specific education for patients and health care providers. From April 2016 to March 2018, 22,137 new patients were eligible for screening. Among those new patients, 13,617 (62%) were screened, with 1382 (10%) being current smokers and 532 (4%) having recently quit (within 6 months). Of the current smokers and those who had recently quit, all were advised to quit or to stay smoke-free, and 380 (20%) accepted referral to a sc counselling service. Conclusions: Here, we provide a comprehensive practice blueprint for the implementation of digitally based sc programs as a standard of care within comprehensive cancer centres with high patient volumes.


Asunto(s)
Instituciones Oncológicas/organización & administración , Neoplasias , Desarrollo de Programa , Cese del Hábito de Fumar/métodos , Comunicación , Humanos , Tamizaje Masivo , Guías de Práctica Clínica como Asunto , Participación de los Interesados , Enseñanza , Flujo de Trabajo
2.
Br J Cancer ; 118(7): 947-954, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29515256

RESUMEN

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) tumour expression may provide added value to human equilibrative nucleoside transporter-1 (hENT1) tumour expression in predicting survival following pyrimidine-based adjuvant chemotherapy. METHODS: DPD and hENT1 immunohistochemistry and scoring was completed on tumour cores from 238 patients with pancreatic cancer in the ESPAC-3(v2) trial, randomised to either postoperative gemcitabine or 5-fluorouracil/folinic acid (5FU/FA). RESULTS: DPD tumour expression was associated with reduced overall survival (hazard ratio, HR = 1.73 [95% confidence interval, CI = 1.21-2.49], p = 0.003). This was significant in the 5FU/FA arm (HR = 2.07 [95% CI = 1.22-3.53], p = 0.007), but not in the gemcitabine arm (HR = 1.47 [0.91-3.37], p = 0.119). High hENT1 tumour expression was associated with increased survival in gemcitabine treated (HR = 0.56 [0.38-0.82], p = 0.003) but not in 5FU/FA treated patients (HR = 1.19 [0.80-1.78], p = 0.390). In patients with low hENT1 tumour expression, high DPD tumour expression was associated with a worse median [95% CI] survival in the 5FU/FA arm (9.7 [5.3-30.4] vs 29.2 [19.5-41.9] months, p = 0.002) but not in the gemcitabine arm (14.0 [9.1-15.7] vs. 18.0 [7.6-15.3] months, p = 1.000). The interaction of treatment arm and DPD expression was not significant (p = 0.303), but the interaction of treatment arm and hENT1 expression was (p = 0.009). CONCLUSION: DPD tumour expression was a negative prognostic biomarker. Together with tumour expression of hENT1, DPD tumour expression defined patient subgroups that might benefit from either postoperative 5FU/FA or gemcitabine.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico , Dihidrouracilo Deshidrogenasa (NADP)/metabolismo , Tranportador Equilibrativo 1 de Nucleósido/metabolismo , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidad , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Fluorouracilo/administración & dosificación , Humanos , Inmunohistoquímica , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Supervivencia , Análisis de Matrices Tisulares , Gemcitabina
3.
Support Care Cancer ; 20(3): 641-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22072050

RESUMEN

PURPOSE: We explored regret in thyroid cancer patients, relating to the decision to accept or reject adjuvant radioactive iodine treatment. METHODS: We studied patients with a recent diagnosis of early stage papillary thyroid carcinoma, in whom treatment decisions on adjuvant radioactive iodine had been finalized. Participants completed a Decision Regret Scale questionnaire. We asked the participants to identify who made the final decision about radioactive iodine treatment. We explored the relationship between decision regret and a) degree of patient involvement in decision-making and b) receipt of radioactive iodine treatment. RESULTS: We included 44 individuals, more than half of whom received adjuvant radioactive iodine treatment (26/44). Decision regret was generally low (mean 22.1, standard deviation [SD] 13.0). Participants reported that the final treatment decision was made by the following: patient and doctor (52.3%, 23/44), completely the patient (27.3%, 12/44), or completely the physician (20.5%, 9/44). Decision regret significantly differed according to who made the final decision: the patient (mean 19.0, SD 11.3), patient and doctor (mean 19.5, SD 7.4), and the doctor (mean 32.9, SD 20.37) (F = 4.569; degrees of freedom = 2, 41; p = 0.016). There was no significant difference in decision regret between patients who received radioactive iodine and those who did not (mean difference -2.5; 95% confidence interval -10.6, 5.6; p = 0.540). CONCLUSION: Thyroid cancer patients who reported being involved in the final treatment decision on adjuvant radioactive iodine had less regret than those who did not.


Asunto(s)
Radioisótopos de Yodo/uso terapéutico , Participación del Paciente , Satisfacción del Paciente , Neoplasias de la Tiroides/radioterapia , Adolescente , Adulto , Toma de Decisiones , Emociones , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Encuestas y Cuestionarios , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adulto Joven
4.
Br J Cancer ; 106(1): 61-9, 2012 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-22134511

RESUMEN

BACKGROUND: Locally advanced inoperable pancreatic cancer (LAPC) has a poor prognosis. By increasing intensity of systemic therapy combined with an established safe chemoradiation technique, our intention was to enhance the outcomes of LAPC. In preparation for phase III evaluation, the feasibility and efficacy of our candidate regimen gemcitabine-oxaliplatin chemotherapy with sandwich 5-fluorouracil (5FU) and three-dimensional conformal radiotherapy (3DCRT) needs to be established. METHODS: A total of 48 patients with inoperable LAPC without metastases were given gemcitabine (1000 mg m(-2) d1 + d15 q28) and oxaliplatin (100 mg m(-2) d2 + d16 q28) in induction (one cycle) and consolidation (three cycles), and 5FU 200 mg m(-2) per day over 6 weeks during 3DCRT 54 Gy. RESULTS: Median duration of sustained local control (LC) was 15.8 months, progression-free survival (PFS) was 11.0 months, and overall survival was 15.7 months. Survival rates for 1, 2, and 3 years were 70.2%, 21.3%, and 12.8%, respectively. Global quality of life did not significantly decline from baseline during treatment, which was associated with modest treatment-related toxicity. CONCLUSION: Fixed-dose gemcitabine and oxaliplatin, combined with an effective and safe regimen of 5FU and 3DCRT radiotherapy, was feasible and reasonably tolerated. The observed improved duration of LC and PFS with more intensive therapy over previous trials may be due to patient selection, but suggest that further evaluation in phase III trials is warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pancreáticas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Calidad de Vida , Resultado del Tratamiento , Gemcitabina
5.
Artículo en Inglés | MEDLINE | ID: mdl-22064208

RESUMEN

OBJECTIVE: The purpose of this randomized, controlled, parallel group study was to characterize the relationships between dosages of stearidonic acid (SDA) and eicosapentaenoic acid (EPA), and incorporation of EPA into red blood cell (RBC) membranes over time. METHODS: Healthy subjects (n=131) received capsules with placebo (safflower oil), SDA (0.43, 1.3, 2.6, or 5.2 g/d) or EPA (0.44, 1.3, or 2.7 g/d) for 12 weeks. RBC fatty acids were analyzed biweekly. RESULTS: RBC %EPA increased in all EPA and SDA groups (p<0.02 vs. control) except the 0.43 g/d SDA group (p=0.187). For theoretical intakes of EPA of 0.25, 0.5, and 0.89 g/d, the amounts of SDA needed to achieve equivalent RBC EPA enrichment were 0.61, 1.89, and 5.32 g/d (conversion efficiencies of 41%, 26%, and 17%), respectively. CONCLUSIONS: SDA increased RBC %EPA in a dosage and time-dependent manner at intakes as low as 1.3 g/d.


Asunto(s)
Ácido Eicosapentaenoico/farmacocinética , Membrana Eritrocítica/metabolismo , Eritrocitos/metabolismo , Ácidos Grasos Omega-3/farmacocinética , Adulto , Cápsulas , Diarrea/inducido químicamente , Relación Dosis-Respuesta a Droga , Ácido Eicosapentaenoico/administración & dosificación , Ácido Eicosapentaenoico/efectos adversos , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Método Simple Ciego , Factores de Tiempo
6.
Clin Endocrinol (Oxf) ; 74(4): 419-23, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21198742

RESUMEN

In patients with early stage papillary thyroid carcinoma (PTC) who have had a thyroidectomy, the decision must be made to accept or reject radioactive iodine remnant ablation (RRA). Counselling patients about this decision can be challenging, given the medical evidence uncertainties and the complexity of related information. Although physicians are the primary source of medical information for patients considering RRA, some patients have a desire for supplemental information from sources such as the internet. Yet, thyroid cancer resources on the internet are of variable quality, and some may not be applicable to the individual case. We have developed a computerized educational tool [called a decision aid (DA)], directed to patients with early stage papillary thyroid cancer, and intended as an adjunct to physician counselling, to relay evidence-based medical information on disease prognosis and the choice to accept or reject RRA. DAs are tools used to inform patients about available treatment options and have been utilized in oncologic decision-making. We tested our web-based DA in fifty patients with early stage PTC and found that it improved medical knowledge. Furthermore, participants found the technical usability of the tool acceptable. We are currently conducting a randomized controlled trial comparing the use of the DA plus usual care to usual care alone to confirm the educational benefit of the website and examine its impact on the decision-making process. In the future, DAs may play an expanded role as an adjunct to physician counselling in the care of patients with thyroid cancer.


Asunto(s)
Toma de Decisiones , Radioisótopos de Yodo/uso terapéutico , Educación del Paciente como Asunto/métodos , Adolescente , Adulto , Carcinoma , Carcinoma Papilar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Programas Informáticos , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/terapia , Tiroidectomía , Adulto Joven
7.
Br J Cancer ; 97(4): 464-71, 2007 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-17653074

RESUMEN

The aim of this phase II study was to assess the feasibility and efficacy of a specific three-dimensional conformal radiotherapy technique with concurrent continuous infusion of 5-fluorouracil (CI 5FU) sandwiched between gemcitabine chemotherapy in patients with locally advanced pancreatic cancer. Patients with inoperable cancer in the pancreatic head or body without metastases were given gemcitabine at 1000 mg m(-2) weekly for 3 weeks followed by a 1-week rest and a 6-week period of radiotherapy and concurrent CI 5FU (200 mg m(-2) day(-1)). The defined target volume was treated to 54 Gy in 30 daily fractions of 1.8 Gy. After 4 weeks' rest, gemcitabine treatment was re-initiated for three cycles (days 1, 8, 15, q28). Forty-one patients were enrolled. At the end of radiotherapy, one patient (2.4%) had a complete response and four patients (9.6%) had a partial response; at the end of treatment, three patients (7.3%) had a complete response and two patients (4.9%) had a partial response. Median survival time was 11.7 months, median time to progression was 7.1 months, and median time to failure of local control was 11.9 months. The 1- and 2-year survival rates were 46.3 and 9.8%, respectively. Treatment-related grade 3 and 4 toxicities were reported by 16 (39.0%) and four (9.8%) patients, respectively. Sixteen out of 41 patients did not complete the planned treatment and nine due to disease progression. This approach to treatment of locally advanced pancreatic cancer is safe and promising, with good local control for a substantial proportion of patients, and merits testing in a randomised trial.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Desoxicitidina/análogos & derivados , Fluorouracilo/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Radioterapia Conformacional , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Quimioterapia Adyuvante/efectos adversos , Terapia Combinada/efectos adversos , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Estudios de Factibilidad , Femenino , Fluorouracilo/efectos adversos , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Radioterapia Asistida por Computador/efectos adversos , Radioterapia Conformacional/efectos adversos , Análisis de Supervivencia , Resultado del Tratamiento , Gemcitabina
8.
Biomed Pharmacother ; 61(1): 97-103, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17011740

RESUMEN

Targeted drug delivery requires binding of (and subsequent uptake by) the carrier to target cells. The purpose of our present study is to compare the binding and uptake of emulsions with different electric surface properties to SK-BR3 cell line, which over-expresses the HER2 receptor. Cationic emulsion was prepared by incorporating 0.25% w/w of the cationic lipid, stearylamine in the formulation while the anionic emulsion formulation was identical but lacking stearylamine. Immunoemulsions were prepared by conjugating the 2-iminothiolane derivative of the monoclonal antibody trastuzumab (Herceptin) through the reactive maleimide group of the octadecyl-4-(maleimidomethyl)cyclohexane-carboxylic amide linker which was incorporated in the oil phase of the anionic and cationic emulsions. Cationic emulsion exhibited a droplet size of approximately 130 nm and a zeta potential of +50 mV compared to anionic emulsion with a droplet size of approximately 140 nm and a zeta potential of -30 mV which decreased to -5 mV following antibody coupling. There was no significant difference in the coupling efficiency of trastuzumab to anionic and cationic emulsions which was in the range of 60-70%. The cationic emulsion and immunoemulsion appeared to be physically stable over a long period of time, as indicated by particle-size measurements while the droplets of the anionic immunoemulsion coalesced with time resulting in phase separation within 20 days storage at 4 degrees C. The results of binding and uptake to cells showed that both cationic and anionic immunoemulsions bind and internalized to cells much more than the respective blank emulsions. The enhanced penetration of the probe coumarin-6 with both immunoemulsions clearly indicated that the internalization process was mainly controlled by a cell-receptor endocytosis mechanism mediated by the binding affinity of trastuzumab to the cell surface receptor since the uptake of the cationic immunoemulsion was not significantly different from the uptake of the anionic immunoemulsion. However, only the cationic immunoemulsion might be considered for further investigation in view of its long standing physical stability.


Asunto(s)
Anticuerpos/química , Emulsiones/química , Aceites de Plantas/química , Aniones , Anticuerpos/metabolismo , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales Humanizados , Transporte Biológico , Neoplasias de la Mama , Cationes , Línea Celular Tumoral , Emulsiones/farmacocinética , Femenino , Humanos , Cinética , Propiedades de Superficie , Trastuzumab
9.
Br J Cancer ; 92(5): 832-7, 2005 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-15756253

RESUMEN

This study determined the efficacy and safety of a modified FOLFOX regimen that improved patient convenience without compromising oxaliplatin dose intensity. A total of 62 patients with previously untreated metastatic colorectal cancer were enrolled to receive, entirely as outpatients, 2-weekly cycles of oxaliplatin 100 mg m(-2) i.v. over 2 h, together with leucovorin 400 mg m(-2) over 2 h, 5-fluorouracil (5-FU) 400 mg m(-2), bolus, followed by a 46-h infusion of 5-FU at 2.4 g m(-2). Treatment was given until progression or unmanageable toxicity. In all, 61 patients received > or =one oxaliplatin dose and a median of 11 treatment cycles (range 1-20 cycles); 22 (36%) reported grade 3/4 neutropenia and 13 patients (21%) experienced grade 3 neurotoxicity; 16 patients (26%) discontinued treatment due to disease progression or death, 15 (25%) due to neurotoxicity and six (10%) due to haematological toxicity. Of the 56 eligible patients, complete or partial responses were observed in 29 or 52% (95% confidence interval 38-65%). Median progression-free survival was 8.2 months (7.1-9.9) and median overall survival was 18.7 months (14.0-23.4). In our experience, a modified schedule of FOLFOX improves convenience without compromising efficacy or toxicity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/uso terapéutico , Leucovorina/uso terapéutico , Compuestos Organoplatinos/uso terapéutico , Neoplasias del Recto/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Australia , Quimioterapia Adyuvante , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Hospitalización/estadística & datos numéricos , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Análisis de Supervivencia
10.
Proc Natl Acad Sci U S A ; 98(9): 5078-83, 2001 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-11287634

RESUMEN

Human history is punctuated by periods of rapid cultural change. Although archeologists have developed a range of models to describe cultural transitions, in most real examples we do not know whether the processes involved the movement of people or the movement of culture only. With a series of relatively well defined cultural transitions, the British Isles present an ideal opportunity to assess the demographic context of cultural change. Important transitions after the first Paleolithic settlements include the Neolithic, the development of Iron Age cultures, and various historical invasions from continental Europe. Here we show that patterns of Y-chromosome variation indicate that the Neolithic and Iron Age transitions in the British Isles occurred without large-scale male movements. The more recent invasions from Scandinavia, on the other hand, appear to have left a significant paternal genetic legacy. In contrast, patterns of mtDNA and X-chromosome variation indicate that one or more of these pre-Anglo-Saxon cultural revolutions had a major effect on the maternal genetic heritage of the British Isles.


Asunto(s)
Evolución Cultural , ADN Mitocondrial/genética , Evolución Molecular , Filogenia , Cromosoma X/genética , Cromosoma Y/genética , Emigración e Inmigración/historia , Femenino , Variación Genética/genética , Haplotipos/genética , Historia Antigua , Humanos , Masculino , Repeticiones de Microsatélite/genética , Noruega/etnología , Linaje , Siria , Turquía , Reino Unido/etnología
11.
C R Acad Sci III ; 323(2): 167-72, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10763435

RESUMEN

Inversions of short genomic sequences may play a central role in the generation of protein complexity. We report here the existence of an heterogeneous group of proteins (the trefoil precursors MUC-1 and MUA-1, six preproendothelins, and five classes of zinc finger knot proteins) having both cysteine signatures (Cs) and their inverse complementary sequences (Cs) in the same polypeptide chain. We have also found cases in which the (Cs) of a given signature is not present in the same protein, but elsewhere. TGEKPYK, a cysteine-free motif of the human transcription factor, Krab, coexists with its inverse complementary sequence in 31 proteins; the inverse complementary alone is present in a great number of proteins. Our findings suggest that short DNA inversions are a widespread feature of the genome.


Asunto(s)
Cisteína , Proteínas/química , Proteínas/genética , Secuencia de Aminoácidos , ADN/química , Endotelina-1 , Endotelinas/química , Endotelinas/genética , Humanos , Datos de Secuencia Molecular , Mucina-1/química , Mucina-1/genética , Precursores de Proteínas/química , Precursores de Proteínas/genética , Homología de Secuencia , Factores de Transcripción/química , Factores de Transcripción/genética , Transposasas/química , Transposasas/genética , Dedos de Zinc
12.
Mt Sinai J Med ; 66(2): 106-8, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10100414

RESUMEN

We report a case of acute colonic obstruction initially presumed to be secondary to acute diverticulitis, necessitating emergent surgical intervention. Pathologic examination failed to reveal evidence of inflammation, fibrosis or neoplasia. Marked hypertrophy of the sigmoid circular muscle layer was documented and thought to be the etiology of the colonic obstruction.


Asunto(s)
Colon Sigmoide/patología , Obstrucción Intestinal/etiología , Enfermedad Aguda , Anciano , Bario , Colon Sigmoide/diagnóstico por imagen , Colon Sigmoide/cirugía , Diagnóstico Diferencial , Enema , Humanos , Hiperplasia , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/cirugía , Masculino , Músculo Liso/diagnóstico por imagen , Músculo Liso/patología , Músculo Liso/cirugía , Radiografía
14.
Mol Cell Neurosci ; 11(1-2): 36-46, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9608532

RESUMEN

To ascertain the function of an orphan nuclear receptor Nurr1, a transcription factor belonging to a large gene family that includes receptors for steroids, retinoids, and thyroid hormone, we generated Nurr1-null mice by homologous recombination. Mice, heterozygous for a single mutated Nurr1 allele, appear normal, whereas mice homozygous for the null allele die within 24 h after birth. Dopamine (DA) was absent in the substantia nigra (SN) and ventral tegmental area (VTA) of Nurr1-null mice, consistent with absent tyrosine hydroxylase (TH), L-aromatic amino acid decarboxylase, and other DA neuron markers. TH immunoreactivity and mRNA expression in hypothalamic, olfactory, and lower brain stem regions were unaffected. L-Dihydroxyphenylalanine treatments, whether given to the pregnant dams or to the newborns, failed to rescue the Nurr1-null mice. We were unable to discern differences between null and wild-type mice in the cellularity, presence of neurons, or axonal projections to the SN and VTA. These findings provide evidence for a new mechanism of DA depletion in vivo and suggest a unique role for Nurr1 in fetal development and/or postnatal survival.


Asunto(s)
Proteínas de Unión al ADN , Dopamina/biosíntesis , Hipotálamo/metabolismo , Neuronas/metabolismo , Sustancia Negra/metabolismo , Factores de Transcripción/genética , Área Tegmental Ventral/metabolismo , Animales , Biomarcadores , Química Encefálica/genética , Dopamina/deficiencia , Dopamina/fisiología , Exones , Femenino , Heterocigoto , Levodopa/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes Neurológicos , Mutagénesis Insercional , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Fenotipo , Embarazo , ARN Mensajero/análisis , Sustancia Negra/patología , Factores de Transcripción/deficiencia , Área Tegmental Ventral/patología
15.
Free Radic Biol Med ; 24(2): 252-8, 1998 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9433900

RESUMEN

Myocardial deterioration is relentlessly progressive in almost all patients who develop overt symptoms. Many dilated cardiomyopathies are associated with a marked increase in cardiac sympathetic tone which may be toxic to myocytes. Microvascular spasm, leading to diffuse, focal reperfusion injury, also appears to be an important mechanism of cardiomyocyte loss in many models of dilated cardiomyopathy. Free radicals may mediate both catecholamine-induced damage and reperfusion injury. We hypothesized that myocardial antioxidant reserve may be significantly reduced in dilated cardiomyopathy and that alpha-tocopheryl acetate may be of benefit. The enzymes superoxide dismutase, catalase and glutathione peroxidase were measured in the myocardial tissue of control and cardiomyopathic hamsters in early (25-50 days) and late (275-320 days) stages of the cardiomyopathy. In another study, myocardial glutathione peroxidase activity and protein oxidation was measured in control and late stage cardiomyopathic hamsters receiving alpha-tocopheryl (70 mg/kg/day) or vehicle for 1 month. There were no significant differences in glutathione peroxidase activity between control and cardiomyopathic hamsters in the early stage of the cardiomyopathy. Superoxide dismutase and catalase activities did not change with aging; however, glutathione peroxidase decreased over 30%, alpha-tocopherol was reduced by approximately 50% and protein oxidation increased more than 2-fold in the hearts of late stage cardiomyopathic hamsters. Alpha-tocopheryl acetate administration restored alpha-tocopherol levels, glutathione peroxidase activity and protein oxidation to normal. We conclude that the decompensating heart has significantly limited antioxidant reserve and that this reserve is sensitive to the intake of antioxidant supplements.


Asunto(s)
Cardiomiopatía Dilatada/metabolismo , Estrés Oxidativo , Vitamina E/análogos & derivados , Vitamina E/metabolismo , alfa-Tocoferol/análogos & derivados , Animales , Cardiomiopatía Dilatada/tratamiento farmacológico , Catalasa/metabolismo , Cricetinae , Glutatión Peroxidasa/metabolismo , Masculino , Mesocricetus , Miocardio/metabolismo , Oxidación-Reducción , Proteínas/metabolismo , Superóxido Dismutasa/metabolismo , Tocoferoles , Vitamina E/uso terapéutico
17.
Healthc Financ Manage ; 51(4): 98-9, 101-3, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10166285

RESUMEN

Physician equity alliances are becoming attractive alternatives to PHOs as integrative models for partnering with physicians, securing managed care contracts and increasing revenue. Unlike many PHOs, these alliances provide mechanisms for asset integration and long-term relationships along with utilization management, sophisticated information systems, access to capital and opportunities for physicians to integrate clinically. There are six major types of physician equity alliances: majority physician-owned, clinic without walls, health system joint venture, publicly held physician practice management company, specialty network, and venture capital. The type of alliance that a physician group practice ultimately develops depends on vision, values, method of capitalization, initial organizer of the alliance, level of involvement of physicians in business issues, corporate structure desired, and characteristics of the managed care market in which the alliance will operate.


Asunto(s)
Redes Comunitarias/organización & administración , Práctica de Grupo/organización & administración , Asociaciones de Práctica Independiente/organización & administración , Administración de la Práctica Médica/organización & administración , Financiación del Capital , Redes Comunitarias/clasificación , Redes Comunitarias/economía , Prestación Integrada de Atención de Salud/tendencias , Práctica de Grupo/economía , Práctica de Grupo/tendencias , Convenios Médico-Hospital , Humanos , Asociaciones de Práctica Independiente/economía , Modelos Organizacionales , Propiedad , Administración de la Práctica Médica/economía , Estados Unidos
18.
J Psychoactive Drugs ; 28(3): 267-90, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8895112

RESUMEN

This paper investigates the supposedly psychedelic Bufo toad and the allegedly psychedelic drug bufotenine, which is contained in the skin and glands of this toad. The bufo toad has held a place in human mythologies and medicines worldwide since archaic times. Used by ancient peoples for a variety of purposes, its most spectacular effects, according to lore, involve magical and shamanic or occult uses for casting spells and for divination. In the Middle Ages, the Bufo toad was celebrated as a panacea and persecuted as a powerful poison. More recently, in the 1960s the Bufo toad was resurrected as a countercultural icon, with people purportedly licking or smoking the secretions to get high. Bufotenine has been at the center of a scientific debate since its discovery in 1893. This paper examines the extensive literature surrounding the Bufo toad and bufotenine, and untangles many of the myths and the misinformation that continue to vex both science and popular reporting. Finally, to promote further investigation, a comprehensive bibliography is provided that charts the history of the Bufo toad and bufotenine.


Asunto(s)
Bufonidae/metabolismo , Bufotenina/farmacología , Alucinógenos/farmacología , Animales , Bufotenina/biosíntesis , Bufotenina/historia , Alucinógenos/historia , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia Medieval , Humanos , Magia/historia , Trastornos Relacionados con Sustancias/psicología
19.
J Am Soc Nephrol ; 6(5): 1468-75, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8589325

RESUMEN

Rats of the Milan normotensive rat strain (MNS) spontaneously develop severe proteinuria and excessive glomerular thromboxane (Tx)A2 production at a young age. These abnormalities are accompanied by podocyte alterations, progressive focal glomerulosclerosis (FGS), and interstitial fibrosis, resembling human FGS. Since it has been shown that pharmacologic Tx-synthase inhibition protects MNS rats from these changes, it was hypothesized that a fish oil (FO) enriched diet, by enhancing TxA3 production instead of TxA2, might afford similar protection, compared with diets enriched in safflower oil (SO) or lard (LD). Rats were pair-fed 11% fat diets from age of 1 to 11 months. Glomerular TxA2 at 11 months was significantly lower in PO-fed rats than in SO- and LD-fed rats (11 +/- 3.0, 69 +/- 3.0, 59 +/- 19.0 nanograms per min/mg, respectively; P < 0.001). At 3 months, urinary albumin excretion was similar among the groups. Over the course of the study, rats fed FO developed significantly less albuminuria than the SO and LD groups (P < 0.001 by analysis of variance for repeated measures), such that the values at 11 months were 25 +/- 5.8, 49 +/- 8.7, and 68 +/- 13.0 mg/24h, respectively. Serum cholesterol and triglycerides were also significantly lower in FO-fed rats than in SO- and LD-fed rats. The extent of FGS was similar in the three groups, but FO-fed rats had less interstitial injury than the other groups. It was observed that a fish-oil diet substantially alleviated albuminuria, normalized nephrotic hyperlipidemia, and reduced interstitial injury, but did not prevent the development of FGS in the MNS model.


Asunto(s)
Aceites de Pescado/uso terapéutico , Glomeruloesclerosis Focal y Segmentaria/dietoterapia , Hiperlipidemias/dietoterapia , Albuminuria/prevención & control , Animales , Creatinina/sangre , Glomeruloesclerosis Focal y Segmentaria/complicaciones , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Hematócrito , Lípidos/sangre , Masculino , Microscopía Electrónica , Distribución Aleatoria , Ratas , Albúmina Sérica/metabolismo
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