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2.
Poult Sci ; 92(8): 1972-80, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23873543

RESUMEN

A major skeletal problem of conventionally caged hens is increased susceptibility to osteoporosis mainly due to lack of exercise. Osteoporosis is characterized by a progressive decrease in mineralized structural bone. Whereas considerable attention has been given to enriching laying cages, little research has been conducted on providing caged pullets with furnishments, in particular perches. The objective of the current study was to determine if metal perches during all or part of the life cycle of White Leghorns affected hen musculoskeletal health, especially at end of lay. Treatments during the pullet phase (hatch to 16.9 wk) entailed cages with and without perches. Four treatments were used during the laying phase (17 to 71 wk of age). Treatment 1 chickens never had access to perches at any point during their life cycle, typical of egg industry practices in the United States for conventional cages. Treatment 2 chickens had access to perches only during the egg-laying phase, which was from 17 to 71 wk of age. Treatment 3 chickens had access to perches only during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had perch access throughout their entire life cycle (0 to 71 wk of age). Musculoskeletal health was assessed by measuring muscle weights, bone mineralization, bone fracture incidence, and keel bone deviations. Muscle deposition of 71-wk-old hens increased when given access to perches as pullets. Bone mineralization of 71-wk-old hens also increased if given perch access as adults. However, the disadvantage of the adult perch was the higher incidence of keel deviations and keel fractures at end of lay. The increase in bone mineralization of the keel bone as a result of perch access during the pullet and laying phases was not great enough to prevent a higher incidence of keel bone fractures at end of lay. Perch redesign and placement of perches within the cage to minimize keel fractures and deviations are possible solutions.


Asunto(s)
Bienestar del Animal , Pollos/fisiología , Vivienda para Animales , Oviposición/fisiología , Absorciometría de Fotón , Envejecimiento/fisiología , Animales , Densidad Ósea/fisiología , Femenino , Músculo Esquelético
3.
Poult Sci ; 92(2): 310-20, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23300294

RESUMEN

Enrichment of pullet cages with perches has not been studied. Our objective was to determine if access to metal perches during all or part of the life cycle of caged White Leghorns affected egg traits, foot health, and feather condition. Treatment 1 represented control chickens that never had access to perches during their life cycle. Treatment 2 hens had perches only during the egg laying phase of the life cycle (17 to 71 wk of age), whereas treatment 3 chickens had perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens always had access to perches (0 to 71 wk of age). Comparisons between chickens that always had perches with controls that never had perches showed similar performance relative to egg production, cracked eggs, egg weight, shell weight, % shell, and shell thickness. More dirty eggs occurred in laying cages with perches. Feed usage increased resulting in poorer feed efficiency in hens with perch exposure during the pullet phase with no effect during egg laying. Perches did not affect hyperkeratosis of toes and feet. The back claw at 71 wk of age broke less if hens had prior experience with perches during the pullet phase. In contrast, during egg laying, the back claw at 71 wk of age broke more due to the presence of perches in laying cages. Perches in laying cages resulted in shorter trimmed claws and improved back feather scores, but caused poorer breast and tail feather scores. In conclusion, enriching conventional cages with perches during the entire life cycle resulted in similar hen performance compared with controls. Fewer broken back claws but poorer feed efficiency occurred because of prior experience with perches as pullets. Perch presence during egg laying improved back feather scores with more trimmed nails but caused more dirty eggs, broken back claws, and poorer breast and tail feather scores. Although perches allow chickens to express their natural perching instinct, it was not without causing welfare problems.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Pollos/fisiología , Plumas/fisiología , Reproducción , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Pollos/crecimiento & desarrollo , Huevos/normas , Femenino , Pie/fisiología , Enfermedades del Pie/epidemiología , Enfermedades del Pie/veterinaria , Vivienda para Animales , Queratosis/epidemiología , Queratosis/veterinaria , Óvulo/fisiología , Enfermedades de las Aves de Corral/epidemiología
4.
J Endocrinol Invest ; 35(11): 947-50, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23310924

RESUMEN

Free testosterone (FT) hormonal responses were compared between high-intensity interval exercise (IE) and steadystate endurance exercise (SSE) in endurance trained males (no.=15). IE session was repeated periods of 90-sec treadmill running at 100-110% maximal oxygen uptake (VO2max) and 90-sec active recovery at 40% VO2max for 42-47 min. The SSE session consisted of a continuous 45-min run at 60-65% VO2max. Total work output was equal for each exercise session. A 45-min supine rest control session (CON) was also performed. All three sessions were on separate days. Pre-session (PRE), immediate post-session (POST), and 12-h post-session (12POST) blood samples were collected and used to determine FT, SHBG, LH, 3- α-androstanediol glucuronide (3-α Diol G) and cortisol. Analysis of variance compared IE and SSE biomarker responses to the reference CON session. IE and SSE each caused an increase (p<0.01) in FT, but IE more so than SSE (p<0.05). The 5α-reductase marker 3-α Diol G response at 12POST IE was elevated while FT was reduced (p<0.05); no such change occurred following SSE. These findings suggest IE might produce a more pronounced turnover of FT by androgen sensitive tissue than the SSE form of exercise.


Asunto(s)
Ejercicio Físico/fisiología , Resistencia Física/fisiología , Testosterona/sangre , Adulto , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/sangre , Humanos , Hidrocortisona/sangre , Hormona Luteinizante/sangre , Masculino , Globulina de Unión a Hormona Sexual/metabolismo
5.
Poult Sci ; 91(9): 2114-20, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22912444

RESUMEN

Osteoporosis, a progressive decrease in mineralized structural bone, causes 20 to 35% of all mortalities in caged White Leghorn hens. Previous research has focused on manipulating the egg laying environment to improve skeletal health, with little research on the pullet. The objective of the current study was to determine the effect of perch access on pullet health, bone mineralization, muscle deposition, and stress in caged White Leghorns. From 0 to 17 wk of age, half of the birds were placed in cages with 2 round metal perches, while the other half did not have perches (controls). Bone mineralization and bone size traits were determined in the tibia, femur, sternum, humerus, ulna, radius, and phalange (III carpometacarpal) using dual energy x-ray absorptiometry. Muscle weights were obtained for the breast and left leg (drum and thigh). A sample of pullets from each cage was evaluated for foot health, BW, right adrenal weight, and packed cell volume. Most measurements were taken at 3, 6, and 12 wk of age. Access to perches did not affect breast muscle weight, percentage breast muscle, percentage leg muscle, bone mineral density, bone length, bone width, adrenal weight, packed cell volume, and hyperkeratosis of the foot-pad and toes. There were no differences in BW, bone mineral content, and leg muscle weight at 3 and 6 wk of age. However, at 12 wk of age, BW (P = 0.025), bone mineral content of the tibia, sternum, and humerus (P = 0.015), and the left leg muscle weight (P = 0.006) increased in pullets with access to perches as compared with controls. These results suggest that perch access has beneficial effects on pullet health by stimulating leg muscle deposition and increasing the mineral content of certain bones without causing a concomitant decrease in bone mineral density.


Asunto(s)
Crianza de Animales Domésticos , Pollos , Vivienda para Animales , Glándulas Suprarrenales/anatomía & histología , Envejecimiento , Animales , Densidad Ósea/fisiología , Femenino , Hematócrito , Músculo Esquelético/fisiología , Tamaño de los Órganos , Estrés Fisiológico
6.
Int J Sports Med ; 30(5): 379-82, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19199221

RESUMEN

This study compared cardio-respiratory responses during running wearing a motion control shoe (MC) or a cushioning shoe (CU) in a cross-over single blinded design. Fourteen runners (10F/4M, age=27.3+/-5.1 years, body mass=64.1+/-12.2 kg, height=167.8+/-7.5 cm, VO (2)max=52.3+/-8.8 ml/kg/min) completed a 40-min run at approximately 65% VO (2) max under both shoe conditions. Oxygen uptake (mL/kg/min; L/min), minute ventilation (L/min), respiratory exchange ratio, and heart rate were measured at minutes 8-10, 18-20, 28-30 and 38-40 of exercise. Rating of perceived exertion was obtained at minutes 10, 20, 30 and 40. Two (footwear) by four (time) repeated measures ANOVAs showed no differences between footwear conditions in overall oxygen consumption (MC=36.8+/-1.5 vs. CU=35.3+/-1.4 mL/kg/min, p=0.143), minute ventilation (MC=50.4+/-4 vs. CU=48.5+/-3.8, p=0.147), respiratory exchange ratio (MC=0.90+/-0.01 vs. CU=0.89+/-0.01, p=0.331), heart rate (MC=159+/-3 vs. CU=160+/-3, p=0.926), or rate of perceived exertion. The design of motion control footwear does not appear to affect cardio-respiratory or perceived exertion responses during submaximal running. The findings are specific to the shoes tested. Nonetheless, the outcomes suggest that footwear selection to reduce certain overuse injuries does not increase the work of running.


Asunto(s)
Consumo de Oxígeno/fisiología , Carrera/fisiología , Zapatos , Adolescente , Adulto , Análisis de Varianza , Estudios Cruzados , Prueba de Esfuerzo/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Esfuerzo Físico/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Respiración , Método Simple Ciego , Factores de Tiempo , Adulto Joven
7.
Pediatr Obes ; 14(5): e12493, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30589518

RESUMEN

The roles of obestatin and adropin in paediatric obesity are poorly understood. We compared obestatin and adropin concentrations in younger (n = 21) and older children (n = 14) with Prader-Willi syndrome (PWS) and age and BMI-z-matched controls (n = 31). Fasting plasma obestatin and adropin were higher in younger children with PWS than controls; adropin was also higher in older children with PWS. Growth hormone treatment had no effects on obestatin or adropin in PWS. The ratio of ghrelin to obestatin declined from early to late childhood but was higher in older PWS than older controls. Adropin correlated with fasting glucose in the PWS group only. Changes in the ratio of ghrelin to obestatin may suggest changes in the processing of preproghrelin to ghrelin and obestatin during development and differential processing of preproghrelin in PWS.


Asunto(s)
Ghrelina/sangre , Obesidad Infantil/sangre , Péptidos/sangre , Síndrome de Prader-Willi/sangre , Adolescente , Proteínas Sanguíneas , Índice de Masa Corporal , Peso Corporal , Niño , Preescolar , Femenino , Humanos , Lactante , Resistencia a la Insulina/fisiología , Péptidos y Proteínas de Señalización Intercelular , Masculino
8.
Pediatr Obes ; 13(11): 734-743, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30280511

RESUMEN

BACKGROUND: Physical activity is associated with improved cardiometabolic markers in children with nonsyndromic obesity (NSO). Prader-Willi Syndrome (PWS) is a neurodevelopmental disorder characterized by obesity. OBJECTIVE: To compare cardiometabolic changes in response to a home-based parent-facilitated physical activity intervention between children with PWS or with NSO. METHODS: Participants included 18 children with PWS (age = 10.5 ± 0.7y; body fat = 44.6 ± 2.0%) and 30 children with NSO (age = 9.7 ± 0.2y; body fat = 44.8 ± 1.2%). Active Play @ Home was a 24-week physical activity intervention curriculum containing playground-based and active video games completed 4 days per week. Pre- and post-intervention measurements included physical activity, body composition, blood samples analysed for glucose, insulin, lipids and cytokines, and insulin resistance computed using the homeostatic model of assessment for insulin resistance (HOMA-IR). RESULTS: All children (n = 48) showed a significant decrease in Interleukin-8 (3.64 ± 0.24 vs. 3.06 ± 0.22 pg/mL). Children with obesity who did not gain or who lost body fat percentage (n = 18) demonstrated a significant decrease in HOMA-IR (3.17 ± 0.39 vs. 2.72 ± 0.34) and an increase in high-density lipoprotein (44.30 ± 2.51 vs. 47.29 ± 2.59 mg/dL). All other measurements showed no significant changes. CONCLUSIONS: The most favourable changes in cardiometabolic factors were observed in children with nonsyndromic obesity who demonstrated no gain or a decrease in body fat percentage.


Asunto(s)
Biomarcadores/sangre , Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Obesidad Infantil/terapia , Síndrome de Prader-Willi/terapia , Adolescente , Antropometría/métodos , Glucemia/análisis , Composición Corporal/fisiología , Niño , Citocinas/sangre , Femenino , Humanos , Insulina/sangre , Resistencia a la Insulina/fisiología , Lípidos/sangre , Masculino , Padres , Obesidad Infantil/fisiopatología , Síndrome de Prader-Willi/fisiopatología
9.
J Am Coll Cardiol ; 6(2): 307-10, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3874891

RESUMEN

The incidence, risk factors and long-term prognosis of complex ventricular arrhythmias after coronary artery bypass graft surgery are not known. Complex ventricular arrhythmias are defined as Lown grades 4a (couplets), 4b (ventricular tachycardia) and 5 (R on T phenomenon). Ninety-two patients with normal left ventricular function who underwent elective coronary artery bypass graft surgery were prospectively evaluated. Ventricular arrhythmias were documented by predischarge 24 hour ambulatory electrocardiographic monitoring; 43% of patients had no or simple ventricular arrhythmias (Lown grades 1 to 3) and 57% had complex ventricular arrhythmias. Risk factors analyzed included age, sex, diabetes, hypertension, smoking, preoperative digoxin or propranolol therapy, cardiopulmonary bypass time, aortic cross-clamp time, number of vessels bypassed, peak creatine kinase (CK) elevation and pericarditis. No risk factor identified patients at higher risk for complex ventricular arrhythmias. Patients were followed up for 6 to 24 months (mean 16). Patients with complex ventricular arrhythmias did not have a higher incidence of sudden death, cardiac death, syncope, angina, myocardial infarction or cerebrovascular accident. It was concluded that: Complex ventricular arrhythmias are common after coronary artery bypass graft surgery. None of the risk factors considered identify high risk patients. Complex ventricular arrhythmias after coronary artery bypass graft surgery do not indicate a poor prognosis in patients with normal left ventricular function.


Asunto(s)
Arritmias Cardíacas/etiología , Puente de Arteria Coronaria/efectos adversos , Atención Ambulatoria , Angina de Pecho/cirugía , Arritmias Cardíacas/tratamiento farmacológico , Arritmias Cardíacas/fisiopatología , Digoxina/uso terapéutico , Electrocardiografía , Electrofisiología , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Premedicación , Pronóstico , Propranolol/uso terapéutico , Estudios Prospectivos , Distribución Aleatoria , Riesgo , Factores de Tiempo
10.
Endocrinology ; 132(3): 1305-12, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7679977

RESUMEN

The sites of noncovalent association between the alpha- (common) and beta- (hormone-specific) subunits in the glycoprotein hormones [LH, human CG (hCG), FSH, and TSH] remain to be completely defined. This information is essential to efforts to map the three-dimensional structure of the hormones and to help explain the stability of the hormone heterodimer in the circulation. Among numerous approaches that have been employed to identify these sites of subunit interaction, chemical or photoaffinity cross-linking has the advantage of identifying the complementary sites of contact on the respective subunits. We have used the stable photoaffinity ligand, L-benzoylphenylalanine (Bpa), to evaluate subunit interaction by the hLH beta sequence (1-15). A peptide from this region of hCG beta has been shown previously to inhibit subunit association. The 3H-labeled Bpa was incorporated into the peptide at position 8 (Trp) during solid-phase synthesis. After incubation with alpha under long-wavelength (366 nm) ultraviolet light, a Bpa- (1-15)-labeled-alpha-fraction was isolated. Control experiments showed the binding to be covalent and specific to (1-15). Two other Bpa-labeled beta-fragments, the receptor-binding loop (38-57) and the (30-43) peptide containing the highly conserved CAGY sequence, did not cross-link. The site of contact in alpha was localized by peptide mapping and sequence analysis to the N-terminal fragment (18-33), most likely at Met-29 or Gly-30. Both the alpha- and beta-sites are adjacent to or overlapping receptor-binding regions. Subunit contact sites and receptor-binding segments may thus be oriented in close proximity to provide a multicomponent receptor-binding domain imparting full activity to the native hormone.


Asunto(s)
Gonadotropina Coriónica/metabolismo , Hormonas Glicoproteicas de Subunidad alfa/metabolismo , Hormona Luteinizante/metabolismo , Fenilalanina/análogos & derivados , Marcadores de Afinidad/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Humanos , Hormona Luteinizante/química , Datos de Secuencia Molecular , Mapeo Peptídico , Fenilalanina/metabolismo
11.
Endocrinology ; 141(9): 3080-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10965877

RESUMEN

Homologs of mammalian PTH1 and PTH2 receptors, and a novel PTH3 receptor have been identified in zebrafish (zPTH1, zPTH2, and zPTH3). zPTH1 receptor ligand specificity is similar to that of mammalian PTH1 receptors. The zPTH2 receptor is selective for PTH over PTH-related protein (PTHrP); however, PTH produces only modest cAMP accumulation. A PTH2 receptor-selective peptide, tuberoinfundibular peptide of 39 residues (TIP39), has recently been purified from bovine hypothalamus. The effect of TIP39 has not previously been examined on zebrafish receptors. The zPTH3 receptor was initially described as PTHrP selective based on comparison with the effects of human PTH. We have now examined the ligand specificity of the zebrafish PTH-recognizing receptors expressed in COS-7 cells using a wide range of ligands. TIP39 is a potent agonist for stimulation of cAMP accumulation at two putative splice variants of the zPTH2 receptor (EC50, 2.6 and 5.2 nM); in comparison, PTH is a partial agonist [maximal effect (Emax) of PTH peptides ranges from 28-49% of the TIP39 Emax]. As TIP39 is much more efficacious than any known PTH-like peptide, a homolog of TIP39 may be the zPTH2 receptor's endogenous ligand. At the zPTH3 receptor, rat PTH-(1-34) and rat PTH-(1-84) (EC50, 0.22 and 0.45 nM) are more potent than PTHrP (EC50, 1.5 nM), and rPTH-(1-34) binds with high affinity (3.2 nM). PTH has not been isolated from fish. PTHrP-like peptides, which have been identified in fish, may be the natural ligands for zPTH1 and zPTH3 receptors.


Asunto(s)
Neuropéptidos/farmacología , Proteína Relacionada con la Hormona Paratiroidea , Hormona Paratiroidea/farmacología , Fragmentos de Péptidos/farmacología , Proteínas/farmacología , Receptores de Hormona Paratiroidea/efectos de los fármacos , Pez Cebra/metabolismo , Animales , Células COS , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Indicadores y Reactivos , Ligandos , Ratones , Ensayo de Unión Radioligante , Teriparatido/farmacología
12.
J Mol Endocrinol ; 16(1): 73-80, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8672235

RESUMEN

A cDNA containing the sequence of GH was cloned and sequenced from a pituitary cDNA library for the holostean fish Lepisosteus osseus (common name: gar). The gar GH cDNA contained an open reading frame of 633 nucleotides and a 3' untranslated region (including the terminal codon TAG) of 1058 nucleotides. The overall length of the gar GH cDNA including leader sequence, signal sequence, hormone sequence and 3' untranslated region was 1713 nucleotides. Thus, the gar GH cDNA is the largest vertebrate GH cDNA yet cloned. A comparison of GH sequences from ancient (holostean fishes-gar and bowfin; one chondrostean fish-the Russian sturgeon) and more modern (27 species of teleosts) members of class Actinopterygii indicate that members of this class have maintained many of the invariant residues deemed necessary for GH folding motifs (intramolecular relationships) observed in mammals.


Asunto(s)
Peces/genética , Hormona del Crecimiento/biosíntesis , Hormona del Crecimiento/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Cartilla de ADN , ADN Complementario , Peces/clasificación , Biblioteca de Genes , Hormona del Crecimiento/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
13.
Am J Cardiol ; 74(1): 53-6, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8017307

RESUMEN

A hypercoagulable state exists after orthotopic liver transplantation. This hematologic abnormality may predispose patients to coronary thrombosis and unstable angina. The incidence of postoperative myocardial ischemia in such patients is unknown. Suitable electrocardiograms and clinical events of consecutive patients undergoing orthotopic liver transplantation (n = 45) and major intraabdominal surgery (n = 28) during a 3-month period at a major university teaching hospital and transplant center were examined retrospectively. Clinical myocardial ischemia or ischemic electrocardiographic changes, or both, occurred in 6 transplant patients compared with no patient in the nontransplant or comparison group. In 4 of the 6 patients with dramatic electrocardiographic changes and ischemic events, coronary arteriography failed to demonstrate significant obstructive disease. It is concluded that severe myocardial ischemia may occur in patients after orthotopic liver transplantation in the absence of significant coronary disease. A hypercoagulable state may predispose to coronary thrombosis in this setting, providing insight (and a future model for study) into the development of unstable angina.


Asunto(s)
Trasplante de Hígado/efectos adversos , Isquemia Miocárdica/etiología , Abdomen/cirugía , Adulto , Anciano , Trastornos de la Coagulación Sanguínea/complicaciones , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico , Estudios Retrospectivos
14.
J Thorac Cardiovasc Surg ; 94(3): 331-5, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3306163

RESUMEN

Multiple trials have suggested the use of digoxin, digoxin and propranolol, or timolol to prevent atrial fibrillation after coronary artery bypass grafting. No trial has evaluated the efficacy of digoxin verus propranolol. Furthermore, the predictors of postoperative atrial fibrillation and the long-term consequence of atrial fibrillation that reverts to sinus rhythm have not been established. One hundred fifty patients were randomized to receive no drug, propranolol (20 mg every 6 hours), or digoxin (0.5 mg followed by 0.25 mg daily). Twenty-seven patients were excluded from data analysis. In the remaining 123 patients, no preoperative parameter (age, sex, diabetes, hypertension, smoking, electrocardiographic p wave morphology, or preoperative digoxin or propranolol therapy), intraoperative parameter (bypass time, aortic cross-clamp time, or number of vessels bypassed), or postoperative parameter (peak creatinine kinase, congestive heart failure, or pericarditis) by univariate or multivariate analysis predicted patients at risk for atrial fibrillation. Sustained atrial fibrillation developed in 37.5% of control and 32.6% of digoxin-treated patients. Only 16.2% of propranolol-treated patients had sustained atrial fibrillation (p less than 0.03). There were no in-hospital complications in those patients with atrial fibrillation. After 26 +/- 7 months follow-up, those patients with postoperative atrial fibrillation had no increased incidence of angina, cerebral vascular accident, myocardial infarction, or sudden death. Therefore, in this select population, propranolol prophylaxis is effective but discretionary.


Asunto(s)
Fibrilación Atrial/prevención & control , Puente de Arteria Coronaria/efectos adversos , Fibrilación Atrial/etiología , Ensayos Clínicos como Asunto , Digoxina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Propranolol/uso terapéutico , Distribución Aleatoria , Riesgo , Factores de Tiempo
15.
J Am Soc Echocardiogr ; 5(2): 173-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1571173

RESUMEN

Coronary artery fistulas are relatively uncommon and are usually initially suspected on auscultation of a continuous murmur. Long-term complications include congestive heart failure, endocarditis, ischemia, and atrial arrhythmias. The role of echocardiography in visualization and diagnosis of these fistulas is expanding. We report two cases in which transesophageal echocardiography was used to visualize and better define proximal coronary arteries and coronary artery fistulas.


Asunto(s)
Anomalías de los Vasos Coronarios/diagnóstico por imagen , Ecocardiografía , Fístula/diagnóstico por imagen , Adulto , Anomalías de los Vasos Coronarios/cirugía , Femenino , Fístula/congénito , Fístula/cirugía , Humanos , Persona de Mediana Edad
16.
Radiol Clin North Am ; 35(1): 21-44, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8998208

RESUMEN

MR imaging of the knee is highly accurate for the noninvasive diagnosis of meniscal tears and other meniscal pathology. Familiarity with the normal anatomy and common pitfalls reduces errant interpretations, but does not eliminate them entirely. The two MR imaging signs of a meniscal tear are abnormal intrameniscal signal on a short-TE image that unequivocally contacts the meniscal surface, and abnormal meniscal morphology in the absence of prior meniscal surgery. To help guide the treatment of meniscal injuries, which continues to evolve, the MR imaging report should thoroughly describe tears, and not simply indicate whether a meniscal tear is present. In the patient with an ACL tear, the accuracy of MR imaging examination for meniscal tears, especially lateral tears, diminishes but still surpasses that of physical examination. The MR imaging criteria for meniscal tears need to be modified in patients who have undergone meniscal surgery.


Asunto(s)
Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Humanos , Artropatías/diagnóstico , Meniscos Tibiales/patología
17.
Neurosurgery ; 44(4): 881-6; discussion 886-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10201317

RESUMEN

OBJECTIVE: Extremely high flow through arteriovenous malformations (AVMs) may limit the safety and effectiveness of endovascular glue therapy. To achieve a more controlled deposition of glue, we used transient but profound systemic hypotension afforded by an intravenously administered bolus of adenosine to induce rapidly reversible high-degree atrioventricular block. METHODS AND CASE REPORT: A patient with a large high-flow occipital AVM fed primarily by the posterior cerebral artery underwent n-butyl cyanoacrylate glue embolization. Nitroprusside-induced systemic hypotension did not adequately reduce flow through the nidus, as determined by contrast injection in the feeding artery. In a dose-escalation fashion, boluses of adenosine were administered to optimize the dose and verify that there was no flow reversal in the AVM and no other unexpected hemodynamic abnormalities by arterial pressure measurements and transcranial Doppler monitoring of the posterior cerebral artery feeding the AVM. Thereafter, 64 mg of adenosine was rapidly injected as a bolus to provide 10 to 15 seconds of systemic hypotension (approximately 20 mm Hg). Although there were conducted beats and some residual forward flow through the AVM during this time, the mean systemic and feeding artery pressures were roughly similar and remained relatively constant. A slow controlled injection of n-butyl cyanoacrylate glue was then performed, with excellent filling of the nidus. CONCLUSION: Adenosine-induced cardiac pause may be a viable method of partial flow arrest in the treatment of cerebral AVMs. Safe, deep, and complete embolization with a permanent agent may increase the likelihood of endovascular therapy's being curative or may further improve the safety of microsurgical resection.


Asunto(s)
Adenosina/uso terapéutico , Embolización Terapéutica , Bloqueo Cardíaco , Malformaciones Arteriovenosas Intracraneales/terapia , Adhesivos , Adulto , Electrocardiografía , Enbucrilato , Femenino , Humanos
18.
Top Magn Reson Imaging ; 9(6): 348-59, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9894738

RESUMEN

Magnetic resonance (MR) imaging of the joints with routine pulse sequences can show the three main categories of osteochondral and chondral injuries: osteochondral fractures, osteochondritis dissecans, and chondral fractures. Detecting acute osteochondral fractures, which frequently accompany ligament tears, may modify patient treatment and ultimately may prove important in long-term prognostication. Staging osteochondritis dissecans lesions is possible with MR imaging and can be used to guide therapy, both surgical and nonsurgical. Specific treatment for chondral fractures is evolving; preoperative diagnosis using MR imaging is advantageous because these lesions often are not initially suspected, they are radiographically occult, and they clinically mimic other internal derangements, for which therapy differs. The MR imaging finding that these traumatic lesions share is the frequent presence of an abnormality in the subchondral bone. Fat-suppressed images are the key to detecting subtle areas of subchondral edema, which in turn may draw attention to a defect in the overlying articular surface.


Asunto(s)
Cartílago Articular/lesiones , Fracturas Óseas/diagnóstico , Articulaciones/lesiones , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Osteocondritis Disecante/diagnóstico , Heridas y Lesiones/diagnóstico
19.
J Heart Valve Dis ; 2(5): 558-60, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8269167

RESUMEN

Infection with group G streptococcus is an unusual but virulent cause of endocarditis. Aortitis and abscess formation due to this organism have been described in one previous report, but only at necropsy. We present here a patient with group G streptococcal endocarditis and aortic annular abscess diagnosed during life by transesophageal echocardiography, leading to successful surgical intervention.


Asunto(s)
Absceso/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Ecocardiografía Transesofágica , Endocarditis Bacteriana/diagnóstico por imagen , Prótesis Valvulares Cardíacas , Complicaciones Posoperatorias/diagnóstico por imagen , Infecciones Estreptocócicas/diagnóstico por imagen , Absceso/cirugía , Anciano , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Bioprótesis , Puente de Arteria Coronaria , Endocarditis Bacteriana/cirugía , Humanos , Masculino , Complicaciones Posoperatorias/cirugía , Falla de Prótesis , Reoperación
20.
Spine (Phila Pa 1976) ; 24(23): 2536-41, 1999 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-10626317

RESUMEN

STUDY DESIGN: A cross-sectional and prospective study. OBJECTIVES: To investigate the association between lumbar listhesis in elderly white women and bone mineral density at the spine, hip, radius, and calcaneus. SUMMARY OF BACKGROUND DATA: Several types of degenerative spinal changes have been found to be associated with high bone mineral density at the spine and other body sites. METHODS: Lateral radiographs of the lumbar spine for 1400 elderly women enrolled in the Study of Osteoporotic Fractures were digitized. Listhesis (antero and retro) was assessed at L3-L4, L4-L5, and L5-S1. Bone mineral density was measured at the spine, hip, calcaneus, and the distal and proximal radius. RESULTS: After adjusting the data for age and body mass index, retrolisthesis at L3-L4, L4-L5, and L5-S1 was associated with mean spinal bone mineral density levels that were 9% to 13% higher compared with those levels in women with no listhesis (P < 0.0001). In addition, bone mineral density at the hip and appendicular sites increased from 4% to 9%. The mean lumbar spinal bone mineral density of women with anterolisthesis at L3-L4 was 12% higher (P < 0.05) than that of women with no listhesis; it was the same for both groups at L4-L5 and was 7% lower (P < 0.005) at L5-S1. At L5-S1 the bone mineral density level at the hip and appendicular sites was also lower among the women with anterolisthesis at that level. CONCLUSIONS: This study suggests that retrolisthesis, like other spinal degenerative diseases, is associated with increased spinal bone mineral density. Anterolisthesis, however, may involve a different etiology, because its association with bone mineral density varies by spinal level.


Asunto(s)
Densidad Ósea/fisiología , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiopatología , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/fisiopatología , Anciano , Estudios Transversales , Femenino , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/fisiopatología , Humanos , Osteoporosis/diagnóstico por imagen , Osteoporosis/fisiopatología , Estudios Prospectivos , Radiografía
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