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1.
J Hosp Infect ; 108: 90-93, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33217493

RESUMEN

Hip-fracture patients are vulnerable to the outcomes of COVID-19. We performed a cross-sectional survey to determine measures employed to limit nosocomial spread of COVID-19 in 23 orthopaedic trauma departments in the North-West of England. Nineteen (87%) hospitals admitted patients to a ward prior to a negative swab, and only 9 (39%) patients were barrier nursed. Hip-fracture patients were operated in non-COVID-19-free theatres in 21 (91%) hospitals. Regular screening of doctors working in trauma and elective areas for COVID-19 was undertaken in three (13%) and five (22%) hospitals, respectively. Doctors moved freely between trauma and elective areas in 22 (96%) hospitals.


Asunto(s)
COVID-19/transmisión , Infección Hospitalaria/prevención & control , Fracturas de Cadera/complicaciones , Hospitales/estadística & datos numéricos , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/virología , Prueba de COVID-19/estadística & datos numéricos , Estudios Transversales , Inglaterra/epidemiología , Femenino , Fracturas de Cadera/mortalidad , Fracturas de Cadera/virología , Hospitalización/estadística & datos numéricos , Humanos , Control de Infecciones/métodos , Masculino , Tamizaje Masivo/normas , SARS-CoV-2/genética
2.
J Neurol Neurosurg Psychiatry ; 87(4): 373-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25857661

RESUMEN

OBJECTIVES: To explore phenotypic differences between individuals with sporadic inclusion body myositis (sIBM) who are seropositive for the NT5c1A antibody compared with those who are seronegative. METHODS: Cross-sectional clinical, serological and functional analysis in 25 consecutive participants with sIBM. RESULTS: All participants met criteria for clinically defined or probable sIBM. 18 of 25 participants with sIBM (72%) were seropositive for the NT5c1A antibody. No differences between median age and duration of illness between the two groups were seen. Females have higher odds of being seropositive (OR=2.30). Participants with seropositive sIBM took significantly longer to get up and stand (p=0.012). There were no significant differences between the two groups in terms of distance covered on a 6 min walk. Seropositive participants were more likely to require assistive devices such as a walker or wheelchair for mobility (OR=23.00; p=0.007). A number of secondary (exploratory) outcomes were assessed. NT5c1A seropositive sIBM cases had lower total Medical Research Council (MRC) sum score and MRC sum score on the right (p=0.03 and 0.02, respectively). Participants with the NT5c1A antibody were significantly more likely to have symptoms of dysphagia (OR=10.67; p=0.03) and reduced forced vital capacity (p=0.005). Facial weakness occurred in 50% of seropositive participants while it was only seen in 14% of seronegative participants. CONCLUSIONS: Even though the small sample size limits definite conclusions, our cross-sectional study showed seropositivity to the NT5c1A antibody is associated with greater motor and functional disability in sIBM. The study also suggests more prominent bulbar, facial and respiratory involvement in individuals positive for NT5c1A antibodies.


Asunto(s)
5'-Nucleotidasa/inmunología , Miositis por Cuerpos de Inclusión/complicaciones , Miositis por Cuerpos de Inclusión/inmunología , 5'-Nucleotidasa/análisis , Anciano , Anticuerpos/análisis , Estudios Transversales , Trastornos de Deglución/epidemiología , Trastornos de Deglución/etiología , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Limitación de la Movilidad , Miositis por Cuerpos de Inclusión/fisiopatología , Desempeño Psicomotor , Calidad de Vida , Trastornos Respiratorios/etiología , Trastornos Respiratorios/fisiopatología , Dispositivos de Autoayuda , Enfermedades de la Médula Espinal/etiología , Enfermedades de la Médula Espinal/fisiopatología , Resultado del Tratamiento , Capacidad Vital
4.
Oncogene ; 30(22): 2534-46, 2011 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-21258407

RESUMEN

Birt-Hogg-Dubé (BHD) syndrome is an inherited cancer susceptibility disease characterized by skin and kidney tumors, as well as cystic lung disease, which results from loss-of-function mutations in the BHD gene. BHD is also inactivated in a significant fraction of patients with sporadic renal cancers and idiopathic cystic lung disease, and little is known about its mode of action. To investigate the molecular and cellular basis of BHD tumor suppressor activity, we generated mutant Bhd mice and embryonic stem cell lines. BHD-deficient cells exhibited defects in cell-intrinsic apoptosis that correlated with reduced expression of the BH3-only protein Bim, which was similarly observed in all human and murine BHD-related tumors examined. We further demonstrate that Bim deficiency in Bhd(-/-) cells is not a consequence of elevated mTOR or ERK activity, but results instead from reduced Bim transcription associated with a general loss of TGFß-mediated transcription and chromatin modifications. In aggregate, this work identifies a specific tumor suppressive mechanism for BHD in regulating TGFß-dependent transcription and apoptosis, which has implications for the development of targeted therapies.


Asunto(s)
Apoptosis/genética , Síndrome de Birt-Hogg-Dubé/genética , Células Madre Embrionarias/metabolismo , Proteínas Proto-Oncogénicas/genética , Factor de Crecimiento Transformador beta/metabolismo , Proteínas Supresoras de Tumor/genética , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteína 11 Similar a Bcl2 , Síndrome de Birt-Hogg-Dubé/patología , Cromatina/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas de la Membrana/genética , Ratones , Ratones Mutantes , Serina-Treonina Quinasas TOR/metabolismo , Transcripción Genética
5.
Oncogene ; 28(13): 1594-604, 2009 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-19234517

RESUMEN

Birt-Hogg-Dubé (BHD) syndrome is a tumor-suppressor gene disorder characterized by skin tumors, cystic lung disease and renal cell carcinoma. Very little is known about the molecular pathogenesis of BHD. Clinical similarities between BHD and tuberous sclerosis complex (TSC) suggest that the BHD and TSC proteins may function within a common pathway. The TSC proteins inhibit the activity of the mammalian target of rapamycin complex 1 (TORC1), and in Schizosaccharomyces pombe, Bhd and Tsc1/Tsc2 have opposing roles in the regulation of amino-acid homeostasis. We report here that in mammalian cells, downregulation of BHD reduces the phosphorylation of ribosomal protein S6, an indicator of TORC1 activity. To determine whether folliculin, the product of the BHD gene, regulates mammalian target of rapamycin activity in vivo, we generated a mouse with targeted inactivation of the Bhd gene. The mice developed spontaneous oncocytic cysts and tumors composed of cells that resemble the renal cell carcinomas in BHD patients. The cysts and tumors had low levels of phospho-S6. Taken together, these data indicate that folliculin regulates the activity of TORC1, and suggest a new paradigm in which both inappropriately high and inappropriately low levels of TORC1 activity can be associated with renal tumorigenesis.


Asunto(s)
Carcinoma/genética , Neoplasias Renales/genética , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas/fisiología , Proteínas Supresoras de Tumor/fisiología , Animales , Encéfalo/metabolismo , Carcinoma/metabolismo , Transformación Celular Neoplásica/genética , Células Cultivadas , Femenino , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Neoplasias Renales/metabolismo , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Ovario/metabolismo , ARN Mensajero/metabolismo , Serina-Treonina Quinasas TOR , Testículo/metabolismo
6.
Br J Sports Med ; 39(4): 217-22; discussion 217-22, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15793091

RESUMEN

OBJECTIVES: To investigate body image and psychosocial adjustment among competitive bodybuilders, non-competitive weight trainers, and athletically active men. METHODS: Participants were 40 men in each of the three groups who were assessed on body composition and multiple facets of body image evaluation, investment and anxiety, eating attitudes, and social self esteem. RESULTS: Relative to the other two groups, competitive bodybuilders had greater body mass due to fat-free body mass. Although groups did not differ in their situational body image discomfort, competitive bodybuilders and weight trainers had a more positive global appearance evaluation and were more psychologically invested in their physical appearance. Compared with active controls, men in both weightlifting groups were more satisfied with their upper torso and muscle tone. Competitive bodybuilders reported more mid torso satisfaction than the other two groups. Competitive bodybuilders also wished to be significantly heavier than controls did and reported higher social self esteem but greater eating disturbance. CONCLUSIONS: The findings suggest that competitive bodybuilders as a group are not more "muscle dysmorphic" than either non-competitive weight trainers or physically active men who do not train with weights.


Asunto(s)
Imagen Corporal , Músculo Esquelético/fisiología , Levantamiento de Peso/psicología , Adulto , Composición Corporal/fisiología , Peso Corporal/fisiología , Conducta Competitiva , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Humanos , Masculino , Músculo Esquelético/anatomía & histología , Autoimagen , Levantamiento de Peso/fisiología
7.
Int J Eat Disord ; 30(1): 75-82, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11439411

RESUMEN

OBJECTIVE: The present investigation examined the extent to which participation in a 6-week circuit-weight training program produced changes in participants' body images relative to a matched control group. METHOD: The weight trainers consisted of 39 college students (27 women and 12 men). The control group of 39 individuals did not weight-train currently or within the past year. All participants were pre- and posttested on the Multidimensional Body Self-Relations Questionnaire, the Social Physique Anxiety Scale, and the Physical Self-Efficacy Scale. Weight trainers were also pre- and posttested on muscular strength and assessed on their motives for exercise. RESULTS: The program successfully increased upper- and lower-body strength. In contrast to the comparison group, weight trainers had a significantly improved evaluation of their appearance, greater body satisfaction, reduced social physique anxiety, and enhanced physical self-efficacy. Outcomes were unrelated to the extent of concurrent aerobic exercise and largely unrelated to exercise motives. DISCUSSION: Even a relatively brief weight training program can produce improvements in multiple aspects of body image. Further research should investigate weight training as an adjunct to psychosocial treatments of body dissatisfaction.


Asunto(s)
Imagen Corporal , Terapia por Ejercicio , Levantamiento de Peso , Adolescente , Adulto , Ansiedad , Femenino , Humanos , Masculino , Autoeficacia , Resultado del Tratamiento
9.
Int J Eat Disord ; 29(1): 51-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11135333

RESUMEN

OBJECTIVE: There is widespread public dissemination of research findings and media messages regarding social advantages of physical attractiveness and liabilities of unattractiveness. The purpose of this experimental study was to determine the effects of such information on women's body-image experiences. METHOD: College women (n = 66) listened to one of two audiotapes that detailed research-based information either on the subject of appearance stereotyping and discrimination or on the control topic of television violence and aggression. RESULTS: Although the two conditions did not differentially alter mood, exposure to appearance-related versus control information produced significantly less favorable body-image evaluations. Furthermore, as predicted, women who were schematically invested in their physical appearance were especially susceptible to the deleterious effects of the appearance information. DISCUSSION: The scientific and clinical implications of these findings were discussed, particularly with respect to eating disturbances.


Asunto(s)
Imagen Corporal , Discriminación en Psicología , Identidad de Género , Deseabilidad Social , Estereotipo , Adulto , Femenino , Humanos , Inventario de Personalidad , Estudiantes/psicología
10.
Percept Mot Skills ; 90(2): 453-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10833739

RESUMEN

Antidepressant drugs are frequently prescribed for women and have various side effects, including potential effects on body weight. This experiment examined the effects of information about the weight-related side effects of antidepressants on women's attitudes toward the drugs. 60 college women were randomly assigned to read about one of two drugs, fluoxetine (Prozac) or imipramine (Tofranil). Participants were either told or not told about veridical weight-related side effects, namely, weight loss for Prozac and weight gain for Tofranil. As hypothesized, weight-gain information lowered the personal acceptability of Tofranil, and weight-loss information enhanced the acceptability of Prozac. Although research with clinical populations is required, undergraduate women's decisions about the use of antidepressant medications may be influenced by societal body-image ideals.


Asunto(s)
Antidepresivos/efectos adversos , Actitud Frente a la Salud , Peso Corporal/efectos de los fármacos , Servicios de Información sobre Medicamentos , Adolescente , Adulto , Antidepresivos/uso terapéutico , Femenino , Fluoxetina/efectos adversos , Fluoxetina/uso terapéutico , Humanos , Imipramina/efectos adversos , Imipramina/uso terapéutico , Distribución Aleatoria , Factores Sexuales , Aumento de Peso/efectos de los fármacos , Pérdida de Peso/efectos de los fármacos
11.
Eur J Dermatol ; 10(2): 122-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10694311

RESUMEN

Despite the high prevalence and the accepted psychological aspects of male pattern hair loss, few have characterized the effects of hair loss in representative samples of men in different countries. A representative sample of households in 4 European countries (France, Germany, Italy and the United Kingdom) was contacted by an interviewer and resident males 18-40 years of age (n = 1,717) completed a questionnaire designed specifically to evaluate attitudes to hair loss. The questionnaire was comprised of 78 questions translated and pilot-tested using standard methodology into each local language. Questionnaires queried about self-rated hair loss, satisfaction with hair appearance, noticeability of hair loss to others, and bother, concerns and perceptions about hair loss, as well as general physical health (the SF-12 questionnaire) plus three additional questions about mental health. The self-reported degree of hair loss in men was statistically significantly associated (p < 0.001) with all hair-loss specific effects measured, except "limiting job opportunities". The impact of hair loss was generally consistent in the four countries surveyed, although less pronounced in the United Kingdom. Age was significantly correlated with hair loss (rs = 0.34, p < 0.001). Men with greater hair loss were more bothered, more concerned about looking older due to their hair loss, and less satisfied with their hair appearance. Male pattern hair loss has significant negative effects on hair-loss specific measures in men 18 to 40 years of age in France, Italy, Germany and the UK. The degree that hair loss is perceived as noticeable to others appears to be a significant contributor to these negative effects.


Asunto(s)
Alopecia/psicología , Actitud Frente a la Salud , Adolescente , Adulto , Factores de Edad , Envejecimiento/psicología , Alopecia/clasificación , Francia , Alemania , Estado de Salud , Humanos , Relaciones Interpersonales , Italia , Modelos Lineales , Masculino , Salud Mental , Satisfacción Personal , Prevalencia , Autoimagen , Autoevaluación (Psicología) , Ajuste Social , Encuestas y Cuestionarios , Reino Unido
12.
Br J Dermatol ; 141(3): 398-405, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10583042

RESUMEN

Androgenetic alopecia is a common dermatological condition, with potentially adverse psychosocial sequelae. The present review critically examines scientific evidence concerning the effects of androgenetic hair loss on social processes and psychological functioning, as well as the psychosocial outcomes of medical treatments. Research confirms a negative but modest effect of visible hair loss on social perceptions. More importantly, androgenetic alopecia is typically experienced as a moderately stressful condition that diminishes body image satisfaction. Deleterious effects on self-esteem and certain facets of psychological adjustment are more apparent among women than men and among treatment-seeking patients. Various 'risk factors' vis-à-vis the psychological adversity of androgenetic alopecia are identified. Medical treatments, i.e. minoxidil and finasteride, appear to have some psychological efficacy. A conceptual model is delineated to explain the psychological effects of hair loss and its treatment. Directions for needed research are discussed. Strategies are presented for the clinical management of psychological issues among these patients.


Asunto(s)
Alopecia/psicología , Inhibidores Enzimáticos/uso terapéutico , Calidad de Vida , Alopecia/tratamiento farmacológico , Imagen Corporal , Cultura , Femenino , Finasterida/uso terapéutico , Humanos , Relaciones Interpersonales , Masculino , Minoxidil/uso terapéutico , Autoimagen , Vasodilatadores/uso terapéutico
13.
Percept Mot Skills ; 86(1): 137-8, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9530722

RESUMEN

Alpha hydroxy acids are used extensively by patients and consumers for restorative cutaneous purposes. The current study of 32 patients evaluated the clinical and psychosocial effects of this cosmetic therapy. After 12 weeks, significant clinical improvements were found for facial skin tone and fine wrinkling, as well as for patient-reported satisfaction with physical appearance and with marital or relationship quality.


Asunto(s)
Imagen Corporal , Cosméticos/uso terapéutico , Hidroxiácidos/uso terapéutico , Calidad de Vida , Piel/efectos de los fármacos , Adulto , Cosméticos/farmacología , Cara , Femenino , Humanos , Hidroxiácidos/farmacología , Masculino , Persona de Mediana Edad , Satisfacción Personal , Envejecimiento de la Piel/efectos de los fármacos
14.
Int J Eat Disord ; 22(2): 107-25, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9261648

RESUMEN

OBJECTIVE: Although body-image disturbance is among the diagnostic criteria for anorexia nervosa and bulimia nervosa, the nature and extent of this disturbance have not been precisely identified. This is the purpose of this first meta-analysis of extant research on body image and eating disorders. METHOD: Using contemporary techniques, the meta-analysis systematically examined 66 studies (from 1974 to 1993) of perceptual and attitudinal parameters of body image among anorexics and bulimics relative to control groups. RESULTS: Attitudinal body dissatisfaction, both questionnaire and self-ideal discrepancy measures, produced substantially larger effect sizes than did perceptual size-estimation inaccuracy. Body dissatisfaction measures, whether global or weight/shape related, differentiated bulimic and anorexic groups (with bulimics having more dissatisfaction), whereas perceptual distortion indices did not. Somewhat larger effects occurred with whole-body than with body-part size-estimation assessments. Size distortion among patients with eating disorders appears unlikely to reflect a more generalized sensory/perceptual deficit. DISCUSSION: Scientific, conceptual, and clinical implications of these findings are delineated.


Asunto(s)
Anorexia Nerviosa/psicología , Imagen Corporal , Bulimia/psicología , Constitución Corporal , Estudios de Casos y Controles , Modificador del Efecto Epidemiológico , Femenino , Humanos , Satisfacción Personal , Autoimagen , Encuestas y Cuestionarios
15.
Obes Res ; 5(4): 297-307, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9285835

RESUMEN

Although the stigma of obesity in our society is well documented, the measurement of antifat attitudes has been a difficult undertaking. Two studies were conducted to construct and validate the Antifat Attitudes Test (AFAT). In study 1, college students (110 men and 175 women) completed the preliminary 54-item AFAT and specific indices of body image and weight-related concerns. Psychometric and factor analysis revealed a 47-item composite scale and three internally consistent factors that were uncorrelated with social desirability: Social/Character Disparagement, Physical/Romantic Unattractiveness, and Weight Control/Blame. Several body images correlates of antifat prejudice were identified, and men expressed more negative attitudes than women. Study 2 experimentally examined the effects of information about the controllability of weight on the antifat attitudes of 120 participants. Exposure to information on behavioral vs. biogenetic control led to greater blame of persons who are fat for their body size. The implications of the findings and the potential utility of the AFAT are discussed.


Asunto(s)
Actitud , Obesidad , Prejuicio , Adolescente , Adulto , Constitución Corporal , Imagen Corporal , Peso Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
16.
J Pers Assess ; 64(3): 466-77, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16367722

RESUMEN

The Body-Image Ideals Questionnaire (BIQ) was developed as a unique attitudinal body-image assessment that considers one's perceived discrepancy from and degree of investment in personal ideals on multiple physical attributes. Reliability and validity of the 20-item instrument were examined for a sample of 284 college women. The results indicated that the BIQ consists of two relatively distinct and internally consistent Discrepancy and Importance subscales, as well as their multiplicative composite. The subscales' respective convergent validities vis-à-vis extant body-image measures and specific facets of personality (i.e., public self-consciousness and perfectionism) and psychosocial adjustment (i.e., social anxiety, depression, and eating disturbance) were confirmed. Evidence also supported the incremental validity of multiple self-ideal discrepancies. Effects due to socially desirable responding were inconsequential. Directions for needed basic and clinical research were identified.

17.
Percept Mot Skills ; 78(3 Pt 2): 1168-70, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7936939

RESUMEN

The structure of the attitudinal body-image construct was examined by factor analysis of 11 body-image measures among 279 college women. Results support a distinction between evaluative or affective and cognitive-behavioral investment components. Multiple regression analysis further indicated that the optimal prediction of negative body-image affect requires both evaluative and investment aspects of body image.


Asunto(s)
Afecto , Actitud , Imagen Corporal , Adulto , Peso Corporal , Femenino , Humanos , Inventario de Personalidad/estadística & datos numéricos , Psicometría , Valores de Referencia
18.
Percept Mot Skills ; 78(2): 539-44, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8022678

RESUMEN

This investigation examined the factor structure and correlates of the Reasons for Exercise Inventory among 101 exercising women. Subjects completed the 24-item inventory (with one added item), reported their weekly frequency of exercise, and completed two standardized body-image measures. Factor analysis indicated that, with minor modifications, the instrument has an internally consistent structure with four factors of Appearance/Weight Management, Fitness/Health Management, Stress/Mood Management, and Socializing. Appearance/Weight Management was associated with a more negative body image independent of actual body mass and was the only motive related to self-reported frequency of exercise.


Asunto(s)
Actitud , Ejercicio Físico/psicología , Identidad de Género , Motivación , Inventario de Personalidad/estadística & datos numéricos , Adolescente , Adulto , Afecto , Constitución Corporal , Imagen Corporal , Femenino , Humanos , Persona de Mediana Edad , Resistencia Física , Aptitud Física/psicología , Psicometría , Valores de Referencia , Reproducibilidad de los Resultados
19.
Percept Mot Skills ; 77(3 Pt 2): 1099-103, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8170754

RESUMEN

Substantial research shows less favorable body-image experiences among overweight and obese persons relative to persons of average weight. The purpose of this investigation of body image was to compare 102 enrollees in a commercial, very-low-calorie diet program to 258 age- and weight-matched control subjects. Whereas enrollees were more strongly invested in their physical appearance, they held a more disparaging view of their looks. Relative to the control group, enrollees also felt less healthy, yet their evaluation of and investment in their physical fitness were more positive. Obese persons constitute a heterogeneous population, and those who seek rapid and extensive weight loss in commercial programs may have special body-image concerns and needs.


Asunto(s)
Actitud , Imagen Corporal , Obesidad/psicología , Pérdida de Peso , Adulto , Dieta Reductora/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Obesidad/dietoterapia , Inventario de Personalidad
20.
Free Radic Biol Med ; 15(4): 407-14, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8225022

RESUMEN

Reactive oxygen metabolites generated from xanthine oxidase play an important role in the pathogenesis of ischemia-induced tissue injury. In a hemorrhagic shock model of ischemia-reperfusion, the intracellular enzyme xanthine oxidase was released into the vasculature. This intravascular source of superoxide (O2.-) and hydrogen peroxide (H2O2) interacted reversibly with glycosaminoglycans of vascular endothelium and markedly concentrated xanthine oxidase at cell surfaces, enhancing its ability to produce extensive damage to remote tissues. Rats were made hypotensive by hemorrhage, maintained for 2h, and reinfused with shed blood. Blood samples were obtained prior to hemorrhage and 15, 30, 60, and 90 min after reperfusion for determination of xanthine oxidase (XO), lactate dehydrogenase (LDH), and alanine transaminase (AST). These enzymes were not significantly elevated in control animals. Reperfusion after hemorrhage-induced ischemia resulted in significantly elevated AST and LDH in both low heparin (100 U/h) and high heparin (1000 U/h) groups. Xanthine oxidase was detected in the circulation only after 90 min reperfusion in the low heparin group and was elevated during the entire reperfusion period in the high heparin group. Studies with cultured vascular endothelium showed significant heparin-reversible binding of XO to cellular glycosaminoglycans. These results suggest that XO can gain access to the circulation following ischemia, where it then binds to the vascular endothelial cells to produce site-specific oxidant injury to organs remote from the site of XO release.


Asunto(s)
Choque Hemorrágico/enzimología , Xantina Oxidasa/sangre , Alanina Transaminasa/sangre , Animales , Endotelio Vascular/metabolismo , Radicales Libres , Glicosaminoglicanos/metabolismo , Heparina/sangre , Peróxido de Hidrógeno/sangre , Isquemia , L-Lactato Deshidrogenasa/sangre , Masculino , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión , Superóxidos/sangre
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