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1.
Front Med (Lausanne) ; 8: 591201, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33869240

RESUMEN

Growing concerns about the safety of long-term opioid therapy and its uncertain efficacy for non-cancer pain have led to relatively rapid opioid deprescribing in chronic pain patients who have been taking opioid for years. To date, empirically supported processes for safe and effective opioid tapering are lacking. Opioid tapering programs have shown high rates of dropouts and increases in patient distress and suicidal ideation. Therefore, safe strategies for opioid deprescribing that are more likely to succeed are urgently needed. In response to this demand, the EMPOWER study has been launched to examine the effectiveness of behavioral medicine strategies within the context of patient-centered opioid tapering in outpatient settings (https://empower.stanford.edu/). The EMPOWER protocol requires an efficient process for ensuring that collaborative opioid tapering would be offered to the most appropriate patients while identifying patients who should be offered alternate treatment pathways. As a first step, clinicians need a screening tool to identify patients with Opioid Use Disorder (OUD) and to assess for OUD severity. Because such a tool is not available, the study team composed of eight chronic pain and/or addiction experts has extended a validated screening instrument to develop a brief and novel consensus screening tool to identify OUD and assess for OUD severity for treatment stratification. Our screening tool has the potential to assist busy outpatient clinicians to assess OUD among patients receiving long-term opioid therapy for chronic pain.

2.
Ann Trop Paediatr ; 29(3): 239-42, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19689869

RESUMEN

Pseudomonas aeruginosa is a common infection in immunocompromised patients. However, it can also cause severe infections in otherwise healthy individuals. We describe pseudomonal bacteraemia in a 6-month-old boy with significant obstruction of the nasopharynx by pseudomonal debris, which we termed pseudomembranous nectrotising pharyngitis. To prevent aspiration and suffocation, early recognition and removal of the obstruction by endoscopy is recommended.


Asunto(s)
Bacteriemia/microbiología , Faringitis/diagnóstico , Faringitis/microbiología , Infecciones por Pseudomonas/microbiología , Úlcera/microbiología , Obstrucción de las Vías Aéreas/microbiología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Preescolar , Fisura Anal/microbiología , Humanos , Masculino , Nasofaringe/microbiología , Úlceras Bucales/microbiología , Faringitis/tratamiento farmacológico , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/aislamiento & purificación
3.
Cytogenet Genome Res ; 119(1-2): 15-20, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18160776

RESUMEN

We report a newborn male with multiple congenital anomalies including growth retardation, hypotonia, dysmorphic facies, widely-spaced nipples, micropenis, cryptorchidism, optic nerve hypoplasia, heart disease, and a striking, high-pitched cry. Chromosome analysis revealed de novo partial trisomy 11q due to a der(5)t(5;11)(p15.3;q22). Fluorescence in situ hybridization (FISH) showed loss of the 5p telomere signal on the der(5) chromosome, indicating the infant has partial monosomy 5p in addition to partial trisomy 11q. Among cases involving trisomy 11q, an unusual cry has only been documented in the presence of a der(5)t(5p;11q). This apparent dependence of the abnormal cry on monosomy 5p suggested the same genetic mechanism that occurs in Cri du chat syndrome (CDCS) may be responsible for the atypical cry in der(5)t(5p;11q) individuals. Neither a commercial CDCS probe (LSI D5S23, D5S721) nor a series of BAC clones encompassing distal regions implicated in the CDCS-associated cat-cry were deleted in our patient. These results suggest a second cry-modifying locus maps telomeric to BAC RP11-94J21 in band 5p15.33. This locus may not only cause the abnormal cry in individuals with a der(5)t(5p;11q) but could also contribute to the phenotypic variability and discordant mapping studies observed for CDCS.


Asunto(s)
Anomalías Múltiples/genética , Deleción Cromosómica , Cromosomas Humanos Par 5/genética , Llanto , Hibridación Fluorescente in Situ , Anomalías Múltiples/patología , Humanos , Lactante , Cariotipificación , Masculino
4.
Artículo en Inglés | MEDLINE | ID: mdl-17761409

RESUMEN

The aim of this study was to determine whether supplementation with the n-3 long-chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid in patients with chronic refractory epilepsy is associated with beneficial changes in cerebral biochemistry. In a 3-month pilot randomized double-blind placebo-controlled study, three patients received eicosapentaenoic acid and docosahexaenoic acid daily and four received a placebo. 31-Phosphorus neurospectroscopy showed a decrease in phosphodiesters, an increase in gammaNTP and an increase in the broadband component in the active group over this period, while the opposite changes occurred in the placebo group. Therefore, in chronic refractory epilepsy, omega-3 supplementation may be associated with reduced membrane phospholipid breakdown in the brain, an improvement in brain energy metabolism, and an increased level of phospholipids in membranes and/or vesicle bilayers in cells in the brain. The unfavourable biochemical changes observed in the placebo group may be a feature of chronic intractable epilepsy.


Asunto(s)
Encéfalo/metabolismo , Ácidos Docosahexaenoicos , Ácido Eicosapentaenoico , Epilepsia/tratamiento farmacológico , Ácidos Grasos Omega-3 , Adulto , Anciano , Encéfalo/anatomía & histología , Ácidos Docosahexaenoicos/metabolismo , Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/uso terapéutico , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-3/uso terapéutico , Humanos , Espectroscopía de Resonancia Magnética , Persona de Mediana Edad , Proyectos Piloto , Placebos
5.
Nucleosides Nucleotides Nucleic Acids ; 25(9-11): 1221-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17065095

RESUMEN

Xenotransplantation is one be possible solution for a severe shortage of human organs available for transplantation. However, only a few studies addressed metabolic compatibility of transplanted animal organs. Our aim was to compare activities of adenosine metabolizing enzymes in the heart of different species that are relevant to clinical or experimental xenotransplantation. We noted fundamental differences: ecto-5' nucleotidease (E5' N) activity was 4-fold lower in pig and baboon hearts compared to the human hearts while mouse activity was compatible with human and rat activity was three times higher than human. There also were significant differences in AMP-deaminase (AMPD), adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities. We conclude that differences in nucleotide metabolism may contribute to organ dysfunction after xenotransplantation.


Asunto(s)
Trasplante de Corazón/métodos , Nucleótidos/química , Trasplante Heterólogo/métodos , 5'-Nucleotidasa/biosíntesis , AMP Desaminasa/biosíntesis , Adenosina/química , Adenosina Desaminasa/biosíntesis , Animales , Humanos , Ratones , Papio , Purina-Nucleósido Fosforilasa/biosíntesis , Ratas , Especificidad de la Especie , Porcinos
6.
J Hand Surg Br ; 31(1): 72-5, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16289720

RESUMEN

De Quervain's disease is a stenosing tenovaginitis involving the first extensor compartment of the wrist. The similarity of its symptomatology to a number of other conditions and its controversial aetiology are only a few of the barriers which often delay its diagnosis and treatment. We report the first two cases in the literature of abductor pollicus longus tendon rupture in patients with De Quervain's disease who had been treated with conservative methods. The relevant literature is reviewed.


Asunto(s)
Traumatismos de los Tendones , Tenosinovitis/complicaciones , Adulto , Anciano de 80 o más Años , Síndrome del Túnel Carpiano/complicaciones , Síndrome del Túnel Carpiano/cirugía , Femenino , Humanos , Rotura , Férulas (Fijadores) , Tendones/cirugía
7.
J Clin Oncol ; 12(11): 2453-9, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7964963

RESUMEN

PURPOSE: To discuss the significance of multidrug resistance (MDR) in human lymphomas and to review recent and ongoing clinical trials using MDR modulators. DESIGN: A medical literature search was used to identify articles that reported results on the expression or modulation of MDR in human lymphomas. This review summarizes the various methods for detecting expression of the mdr1 gene in tumor specimens, the patterns of expression in lymphomas, and recent and upcoming clinical trials using modulating agents to reverse MDR. RESULTS: There is considerable variation in the assays used to evaluate the expression of mdr1 in lymphomas. Current methodology includes reverse transcriptase polymerase chain reaction (rt-PCR) for assay of mdr1 mRNA, and immunohistochemistry or flow cytometry for detection of the multidrug transporter, P-glycoprotein (P-gp). The preponderance of evidence suggests that mdr1 expression is relatively low in untreated patients (10% to 20% of lymphomas positive), but increases in patients with recurrent disease (50% to 70% positive). Some evidence suggests that mdr1 expression is a prognostic factor for response to chemotherapy, as well as for subsequent survival. Verapamil and cyclosporine (CsA) have been used as competitive inhibitors of the multidrug transporter P-gp in early clinical trials. Although these studies show some activity in modulating clinical MDR, both verapamil and CsA manifest considerable toxicities at doses below those required for complete inhibition of P-gp function. CONCLUSION: MDR due to the expression of the mdr1 gene is an important factor in the course of patients with lymphomas. Continued clinical trials with more potent and less toxic modulators are needed to define the ultimate benefit of modulating MDR in lymphomas.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Antineoplásicos/uso terapéutico , Resistencia a Múltiples Medicamentos/genética , Linfoma/tratamiento farmacológico , Linfoma/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/aislamiento & purificación , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/fisiología , Ensayos Clínicos como Asunto , Humanos , Linfoma/diagnóstico , Pronóstico
8.
J Clin Oncol ; 13(7): 1726-33, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7602362

RESUMEN

PURPOSE: To describe the course of patients following histologic transformation (HT) from low-grade follicular lymphoma to intermediate- or high-grade non-Hodgkin's lymphoma. PATIENTS AND METHODS: Patients were identified from data bases in the Division of Oncology and the Department of Surgical Pathology. HT was defined as the conversion of a follicular small cleaved-cell or follicular mixed small cleaved-cell and large-cell lymphoma to a diffuse large-cell, diffuse mixed small cleaved-cell and large-cell or any high-grade lymphoma. RESULTS: We analyzed the clinical course of 74 low-grade lymphoma patients with histologically proven transformation occurring from 1965 to 1988. The median time from diagnosis to HT was 66 months, and the median age at HT was 58 years. The median duration of survival after transformation was 22 months. Anatomic extent of disease at HT (limited v extensive, P = .01), prior chemotherapy (none v any, P = .01), and response to therapy (complete v partial or none, P = .005) at time of HT were identified as significant predictors of survival after HT in backward-selection Cox regression analysis. Thirty patients attained a complete response to therapy at HT. They had a median survival duration of 81 months after HT. CONCLUSION: A subset of patients with HT from low-grade follicular lymphoma to intermediate- or high-grade lymphoma enjoys relatively long-term survival. Patients with limited disease and no previous exposure to chemotherapy have the most favorable prognosis.


Asunto(s)
Transformación Celular Neoplásica/patología , Linfoma Folicular/mortalidad , Linfoma Folicular/patología , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Adulto , Anciano , Antineoplásicos/uso terapéutico , Femenino , Humanos , Linfoma Folicular/terapia , Linfoma de Células B Grandes Difuso/patología , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Análisis de Supervivencia , Sobrevivientes
9.
Eur J Surg Oncol ; 31(5): 555-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15922893

RESUMEN

AIMS: We evaluated the clinicopathologic relevance of plasma osteopontin (OPN) level in nasopharyngeal carcinoma patients. METHODS: Seventy-two plasma samples were collected from patients with undifferentiated nasopharyngeal carcinoma (NPC) before radiotherapy. Plasma OPN level was determined by quantitative sandwich enzyme immunoassay. The plasma OPN level was evaluated for its clinicopathologic relevance. RESULTS: The mean plasma OPN level was significantly higher in NPC patients than in normal controls (184.66 vs 75.89 ng/ml, p<0.001). In addition, high OPN level was found in the patients with advanced cancer and was correlated with neck node metastasis (p<0.05). CONCLUSIONS: Our findings indicated a potential role of OPN in the pathogenesis and nodal metastasis of undifferentiated NPC.


Asunto(s)
Neoplasias Nasofaríngeas/sangre , Sialoglicoproteínas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/patología , Estadificación de Neoplasias , Osteopontina
10.
Clin Cancer Res ; 5(11): 3357-63, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10589745

RESUMEN

Protein kinase C (PKC) is an attractive target in cancer therapy. It is overexpressed in a variety of cancers, and nonspecific inhibitors of PKC have demonstrated antitumor activity. Antisense oligonucleotides targeted against PKC-alpha, which have high specificity, can inhibit mRNA and protein expression as well as the growth of tumors in vitro and in vivo. This Phase I study sought to characterize the safety profile and to determine the maximum tolerated dose of antisense to PKC-alpha when administered by continuous infusion in patients. Patients with incurable malignancies received ISIS 3521, a 20-length phosphorothioate oligodeoxynucleotide specific for PKC-alpha. Treatment was delivered over a period of 21 days by continuous i.v. infusion followed by a 7-day rest period. Doses were increased from 0.5 to 3.0 mg/kg/day. Patients continued on the study until evidence of disease progression or unacceptable toxicity was detected. Between August 1996 and September 1997, 21 patients were treated in five patient cohorts. The maximum tolerated dose was 2.0 mg/kg/day. The dose-limiting toxicities were thrombocytopenia and fatigue at a dose of 3.0 mg/kg/day. Pharmacokinetic measurements showed rapid plasma clearance and dose-dependent steady-state concentrations of ISIS 3521. Evidence of tumor response lasting up to 11 months was observed in three of four patients with ovarian cancer. The recommended dose of ISIS 3521 for Phase II studies is 2.0 mg/kg/day when given over a period of 21 days. Side effects are modest and consist of thrombocytopenia and fatigue. Evidence of antitumor activity provides the rationale for Phase II studies in ovarian cancer and other malignancies.


Asunto(s)
Isoenzimas/genética , Neoplasias/tratamiento farmacológico , Oligodesoxirribonucleótidos Antisentido/efectos adversos , Proteína Quinasa C/genética , Adulto , Anciano , Área Bajo la Curva , Secuencia de Bases , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Oligodesoxirribonucleótidos Antisentido/sangre , Oligodesoxirribonucleótidos Antisentido/farmacocinética , Proteína Quinasa C-alfa , Sensibilidad y Especificidad , Tionucleótidos , Tomografía Computarizada por Rayos X
11.
Surg Endosc ; 19(6): 774-9, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15868254

RESUMEN

BACKGROUND: Despite being controversial in the past, many reports on the safe use of laparoscopic surgery in emergency settings have been published. The aim of this study was to investigate the diffusion of laparoscopic surgery in three common surgical emergency operations, namely, appendectomy, cholecystectomy, and simple repair of perforated peptic ulcer (PPU), in a stable population. METHODS: This was a retrospective analysis of the central database of the Hospital Authority (HA) in Hong Kong. Data for patients managed in 14 HA hospitals from 1998 to 2002 were studied. The operation record and discharge record of each patient were also investigated to verify the data. RESULTS: A total of 12,708 patients underwent appendectomy, 2631 patients underwent cholecystectomy, and 2260 patients had simple repair of PPU performed. During the study period, 37.2% of appendectomies, 46.5% of cholecystectomies, and 23.1% of simple repairs of PPU were performed laparoscopically. More than a two-fold increase in the proportion of laparoscopic surgery was observed in each of these three operations. By the end of 2002, the percentage of laparoscopic surgery had increased to 53.5% for appendectomies, 61.3% for cholecystectomies, and 32.9% for simple repairs of PPU. Significantly lower hospital mortality rates and shorter postoperative hospital stay were consistenty observed in patients with laparoscopic surgery of the three emergencies. A wide variation in the use of laparoscopic surgery, ranging from 3.7% to 73.1%, was observed among the 14 HA hospitals. However, there was no correlation in the use of laparoscopic surgery with the volume of operation performed in each hospital (p = 0.933). CONCLUSION: A high diffusion rate on the use of laparoscopic surgery for common surgical emergency was observed in Hong Kong. However, there was also a wide variation in the diffusion rate among the 14 HA hospitals. Efforts to reduce hospital variation for the better dissemination of safe laparoscopic technique may be warranted.


Asunto(s)
Apendicectomía/métodos , Apendicectomía/estadística & datos numéricos , Apendicitis/cirugía , Colecistectomía Laparoscópica/métodos , Colecistectomía Laparoscópica/estadística & datos numéricos , Colecistitis/cirugía , Tratamiento de Urgencia , Laparoscopía/estadística & datos numéricos , Úlcera Péptica Perforada/cirugía , Enfermedad Aguda , Adulto , Humanos , Estudios Retrospectivos
12.
Surg Endosc ; 19(5): 697-701, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15776204

RESUMEN

BACKGROUND: The role of laparoscopic cholecystectomy (LC) in acute cholecystitis remains controversial. The aim of the present study was to determine the incidence, clinicopathological characteristics, and outcome of patients with gallbladder cancer presenting with acute cholecystitis. METHODS: We performed a retrospective analysis of patients with gallbladder cancer who presented with acute cholecystitis and were treated at the public hospitals in Hong Kong between 1998 and 2002. RESULTS: Among 2,700 patients with acute cholecystitis managed with cholecystectomy (1,347 open and 1,353 LC), 63 patients (2.3%) were found to have gallbladder cancer. There were 44 women and 19 men with a mean age of 74.7 (+/-12.8) years. Adenocarcinoma (90.5%) was the most common cancer. The overall median survival was 5 months (95% CI = 2.6-7.4). The 5-year survival rate was 20.8%. Laparoscopic cholecystectomy was attempted in 11 patients and was completed successfully in six of them. There was no difference between the LC and open groups in the complication rate, hospital mortality rate, or survival rate. CONCLUSIONS: In the ethnic Chinese population of Hong Kong, the incidence of gallbladder cancer presenting with acute cholecystitis is higher than the same finding in patients undergoing elective cholecystectomy for cholelithiasis. Long-term survival is possible because such patients may be diagnosed at an early stage of the disease.


Asunto(s)
Adenocarcinoma/diagnóstico , Colecistitis/etiología , Neoplasias de la Vesícula Biliar/diagnóstico , Enfermedad Aguda , Adenocarcinoma/complicaciones , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/cirugía , Carcinoma Ductal de Mama/secundario , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirugía , Colecistectomía Laparoscópica , Colecistitis/epidemiología , Colecistitis/cirugía , Colelitiasis/epidemiología , Colelitiasis/cirugía , Comorbilidad , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Femenino , Neoplasias de la Vesícula Biliar/complicaciones , Neoplasias de la Vesícula Biliar/epidemiología , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/secundario , Neoplasias de la Vesícula Biliar/cirugía , Hong Kong/epidemiología , Mortalidad Hospitalaria , Humanos , Incidencia , Hallazgos Incidentales , Tablas de Vida , Linfoma/diagnóstico , Linfoma/cirugía , Masculino , Persona de Mediana Edad , Siembra Neoplásica , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento
13.
Artículo en Inglés | MEDLINE | ID: mdl-16021912

RESUMEN

We compared concentrations of nucleotide substrates and activities of enzymes of nucleotide metabolism in pig and human blood, heart, and kidney. The most important difference was lower ecto-5-nucleotidase (ESN) activity in both pig hearts and kidney. Furthermore, higher hypoxanthine, inosine, adenine, and uracil, but lower uridine and uric acid concentrations were observed in pig blood as compared to human. A twofold increase in UTP concentration has been observed in pig hearts following 4 h perfusion with human blood. Purine metabolism is an important target for genetic and pharmacological manipulation during xenotransplantations.


Asunto(s)
Purinas/metabolismo , Trasplante Heterólogo/métodos , 5'-Nucleotidasa/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Animales Modificados Genéticamente , Cromatografía Líquida de Alta Presión , Humanos , Riñón/metabolismo , Miocardio/metabolismo , Especificidad de la Especie , Porcinos , Uridina Trifosfato/metabolismo
14.
Artículo en Inglés | MEDLINE | ID: mdl-16021913

RESUMEN

Adenosine (Ado) triggers several protective mechanisms that may attenuate development of heart failure, both locally and systemically. We developed a procedure allowing sustained increase in endogenous Ado production by the combined application of Ado metabolism inhibitors and nucleotide precursors. We found that our procedure attenuate the development of heart failure induced by adriamycin.


Asunto(s)
Adenosina/metabolismo , Antibióticos Antineoplásicos/efectos adversos , Doxorrubicina/efectos adversos , Insuficiencia Cardíaca/inducido químicamente , Animales , Cromatografía Líquida de Alta Presión , Doxorrubicina/farmacología , Ecocardiografía , Insuficiencia Cardíaca/prevención & control , Nucleótidos/química , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
15.
Artículo en Inglés | MEDLINE | ID: mdl-16021915

RESUMEN

Possession of the C34T mutation in AMP deaminase (AMPD1) gene has been shown to be associated with attenuation of the progression of heart failure and improved survival in ischemic heart disease. In this study, we examined the frequency of the mutation in the heart with good and poor cardiac function and in healthy controls. We found that there was no difference in the frequency of the mutation between the patients with heart failure and healthy controls. However, the frequency of the mutation in the healthy donor hearts was much higher when compared to healthy controls or donors with failing hearts.


Asunto(s)
AMP Desaminasa/genética , Insuficiencia Cardíaca/genética , Corazón/fisiología , Mutación , Miocardio/patología , Alelos , Estudios de Casos y Controles , Ecocardiografía , Genotipo , Rechazo de Injerto , Trasplante de Corazón , Hemodinámica , Humanos , Isquemia/patología , Polimorfismo Conformacional Retorcido-Simple , Donantes de Tejidos
16.
Artículo en Inglés | MEDLINE | ID: mdl-16021918

RESUMEN

Possession of the nonsense mutation in AMPD 1 C34T gene has been linked to improved survival in patients with heart failure, possibly by promoting the formation of adenosine. This mutation is known to decrease the activity of AMP-deaminase in skeletal muscle. We have found that the AMPD1 mutation decreases the activity of AMP-deaminase in the heart without changing the activity of any other enzymes of adenine nucleotide metabolism. Protective mechanism of this mutation may be thus induced by local cardiac metabolic changes.


Asunto(s)
AMP Desaminasa/genética , Mutación , Miocardio/metabolismo , Adenina/metabolismo , Adenosina/química , Adenosina/metabolismo , Adenosina Monofosfato/metabolismo , Biopsia , Cromatografía Líquida de Alta Presión , Codón sin Sentido , Genotipo , Heterocigoto , Humanos , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple
17.
Artículo en Inglés | MEDLINE | ID: mdl-16021914

RESUMEN

Ecto-5'-nucleotidase (E5'N) is an extracellular enzyme forming anti-inflammatory and immunosuppressive adenosine. We evaluated whether confrontation of pig heart and endothelial cells with human blood changes the activity of E5'N. Pig hearts were perfused ex vivo with fresh human blood for 4 h. Pig aortic endothelial cells (PAEC) were incubated in vitro with human plasma for 3 h. Ex vivo perfusion of pig heart with fresh human blood resulted in a decrease in E5'N activity to 62% and 61% of initial in wild-type and transgenic pig hearts, respectively. PAEC activity of E5'N decreased to 71% and 50% of initial after 3 h exposure to heat-inactivated and active complement human plasma, respectively, while it remained constant in controls. Pig heart activity of E5'N decreased following exposure to human blood, which may affect adenosine production and exacerbate hyperacute and vascular rejection.


Asunto(s)
5'-Nucleotidasa/antagonistas & inhibidores , 5'-Nucleotidasa/metabolismo , Sangre/metabolismo , Endotelio Vascular/metabolismo , Animales , Animales Modificados Genéticamente , Aorta/metabolismo , Proteínas del Sistema Complemento , Endotelio Vascular/citología , Humanos , Nucleótidos/química , Perfusión , Transducción de Señal , Especificidad de la Especie , Porcinos , Factores de Tiempo , Trasplante Heterólogo
19.
Eur J Cancer ; 39(13): 1881-7, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12932666

RESUMEN

Epigenetic silencing of the p16 and p15 genes by promoter methylation are commonly observed in human epithelial malignancies, including head and neck squamous cell carcinomas (HNSCC). In this study, a methylation-specific polymerase chain reaction (MSP) was used to evaluate the methylation status of the p16 and p15 genes in 73 HNSCC surgical specimens. p16 and p15 gene methylation was also examined in 29 paired metastatic lymph nodes and 29 paired histologically, normal resection margin mucosae. The quantity of cell-free methylated p16 and p15 DNA in the plasma samples of 20 HNSCC patients and 24 healthy controls was also examined using a fluorescence-based real-time PCR assay. The frequencies of p16 and p15 methylation in the primary tumour were 49% and 60%, respectively. Concordant methylation of p16 and p15 in tumour samples and metastatic lymph nodes was found in 59 and 38% of cases, respectively. A significantly higher prevalence of p15 methylation was found in histologically-normal surgical margin epithelia of HNSCC patients with chronic smoking and drinking habits compared with non-smokers and non-drinkers. In addition, methylated p16 and p15 DNA levels were significantly higher in the plasma of HNSCC patients (mean 56 copies/ml plasma and 65 copies/ml plasma, respectively) compared with normal controls (mean 6 copies/ml plasma and 16 copies/ml plasma, respectively). In conclusion, promoter methylation of the p16 and p15 genes is involved in the pathogenesis of HNSCC and may be related to chronic smoking and drinking. The differential levels of methylated p16 and p15 DNA in plasma might be potential useful markers in screening high-risk populations for early HNSCC and monitoring their treatment response.


Asunto(s)
Carcinoma de Células Escamosas/genética , Proteínas de Ciclo Celular , Genes p16/fisiología , Neoplasias de Cabeza y Cuello/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor , Adulto , Anciano , Anciano de 80 o más Años , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Metilación de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos
20.
Front Biosci ; 5: D588-93, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10833467

RESUMEN

The ability to target and inhibit individual gene expression with antisense oligonucleotides has shown promising activity in preclinical cancer models. Recent clinical studies have tested antisense compounds directed against seven cancer related genes including p53, bcl-2, c-raf, H-ras, protein kinase C-alpha, and protein kinase A. Class specific effects of the phosphorothioate backbone common to the first generation of antisense compounds have dominated the side effects of these oligonucleotides. Inhibition of target gene expression has been modest at most, and clinical activity has been primarily anecdotal. Combinations of the antisense compounds with chemotherapy and second-generation oligonucleotides offer promise that these agents might become a standard part of future cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Oligonucleótidos Antisentido/uso terapéutico , Humanos
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