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1.
Ann R Coll Surg Engl ; 97(8): 578-83, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26492903

RESUMEN

INTRODUCTION: Invasive lobular carcinoma (ILC) presents diagnostic and therapeutic challenges as it produces subtle radiological changes. It has been suggested that it is not suitable for breast conserving surgery (BCS). The aim of this study was to ascertain the diagnostic adequacy of modern mammography and ultrasonography in the context of a fast track symptomatic diagnostic clinic in the UK. It also sought to compare the mastectomy, re-excision and BCS rates for ILC with those for invasive ductal carcinoma (IDC). METHODS: A retrospective analysis of prospectively collected data was carried out on all new symptomatic cancers presenting to the one-stop diagnostic clinic of a single breast unit between 1998 and 2007. RESULTS: Compared with IDC, ILC was significantly larger at presentation (46mm vs 25mm), needed re-excision after BCS more often (38.8% vs 22.3%) and required mastectomy more frequently (58.8% vs 40.8%). Although mammography performs poorly in diagnosing ILC compared with IDC, when combined with ultrasonography, sensitivity of the combined imaging was not significantly different between these two histological types. CONCLUSIONS: Provided ultrasonography is performed, standard radiological imaging is adequate for initial diagnosis of symptomatically presenting ILC but some additional preoperative workup should clearly be employed to reduce the higher number of reoperations for this histological type.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Carcinoma Lobular/diagnóstico , Mamografía/métodos , Mastectomía Segmentaria/métodos , Estadificación de Neoplasias , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma Lobular/cirugía , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Ultrasonografía Mamaria/métodos
2.
Eur J Surg Oncol ; 31(2): 122-7, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15698726

RESUMEN

AIM: Four-node axillary sampling for breast cancer is an established method of staging the axilla in the United Kingdom. We report the sensitivity of sentinel node (SN) biopsy and compare it with that of four-node sampling. METHODS: SN identification was attempted in 234 consecutive patients with unifocal breast cancers up to 25 mm in diameter on pre-operative ultrasound. A combination of isotope-labelled nanocolloid and patent blue dye techniques were used and SN were identified in 221 (94.5%). All patients underwent back-up four-node sampling and those with positive sentinel nodes on frozen section (FS) underwent immediate full axillary clearance. RESULTS: Among those patients who had SN successfully identified, an average of 1.38 SN were identified per patient. Histological examination of the SN alone would have identified all node-positive patients that the four-node sample identified. CONCLUSION: In patients who have SN identified, four-node axillary sampling does not provide any additional information.


Asunto(s)
Neoplasias de la Mama/patología , Biopsia del Ganglio Linfático Centinela , Axila/patología , Axila/cirugía , Neoplasias de la Mama/cirugía , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Mastectomía , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Factores de Tiempo , Salud de la Mujer
3.
Eur J Cancer ; 39(1): 52-6, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12504658

RESUMEN

The aim of this study was to assess the efficacy of free-hand percutaneous core biopsy (FHCB) and to determine the role of fine needle aspiration cytology (FNAC) as diagnostic tools for palpable radiologically-suspicious breast lumps. This retrospective study was based on reviewing the clinical records of all patients diagnosed as having breast cancer between January 1999 and December 2000 and patients who had benign lesions, but suspicious breast imaging at triple assessment. Absolute sensitivity of FHCB for diagnosing cancer in palpable lesions was 98.7% compared with 51.3% for FNAC. The difference in the sensitivity of FHCB and FNAC was statistically significant (P<0.005, Wilcoxon matched pair test). Since 94.8% of radiologically-suspicious lumps were shown to be cancers, we advocate FHCB for all patients presenting with radiologically suspicious palpable lumps to our breast clinic. We also conclude that the sensitivity of FHCB for the diagnosis of malignancy in palpable radiologically-suspicious breast lesions is so high that image-guidance is unnecessary.


Asunto(s)
Biopsia con Aguja/métodos , Neoplasias de la Mama/patología , Mama/patología , Biopsia con Aguja/normas , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Diagnóstico por Imagen , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Ann Hum Biol ; 28(5): 522-36, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11572518

RESUMEN

An allometric model was used to determine the important factors related to the decline in forced expiratory volume (FEV1.0) across ages 55-86 years in independently living men and women. Measurements were available from a randomized sample of 181 men and 203 women residing in London, Ontario, Canada. The effects of height, age, sex, adiposity, fat free mass (FFM), grip strength and physical activity (PA) on FEV1.0 were assessed using an allometric model to test the hypothesis that sex differences in lung function would be due in part to sex-related differences in the aforementioned variables and would therefore be eliminated by our analysis. The following model was linearized and parameters were identified using standard multiple regression: FEV1.0 = height(beta1) x FFM(beta2) x grip strength(beta3) x PA(beta4) x exp(beta0 + beta5age + beta6sex + beta7smoking + beta8%body fat) x epsilon. Results indicate that the amount of FFM and heavy intensity physical activity participated in by the elderly may be more important in influencing forced expiratory function than previously recognized. In addition, results from this study have confirmed the importance of age and height in the prediction of FEV1.0 and demonstrated a negative effect of smoking on lung function. Individuals with a greater FFM and physical activity level tended to be associated with an above average lung function performance. The cross-sectional rate of decline in FEV1.0 determined from our model was approximately 12% per decade.


Asunto(s)
Envejecimiento/fisiología , Composición Corporal/fisiología , Volumen Espiratorio Forzado/fisiología , Pulmón/fisiología , Fumar/fisiopatología , Anciano , Anciano de 80 o más Años , Antropometría , Índice de Masa Corporal , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Espirometría
5.
Exp Physiol ; 86(1): 117-26, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11429625

RESUMEN

This study compared the ventilatory response to 20 min of acute isocapnic hypoxia (end-tidal P(O(2)), 50 mmHg) using the technique of dynamic end-tidal forcing in young (Y) and old (O) men. Two groups of non-smoking male subjects (mean +/- s.d. age: Y, 29.8 +/- 6.9 years; O, 73.4 +/- 2.8 years) with similar body size, normal age-predicted spirometry, and normal moderate levels of physical activity were studied. Compared with baseline ventilation in euoxia (10.79 +/- 1.99 and 11.88 +/- 0.91 l min-1) both groups responded to the abrupt onset of isocapnic hypoxia with peak ventilatory responses of 22.58 +/- 2.60 and 24.56 +/- 2.54 l min-1 for Y and O, respectively (not significant, n.s.). Both groups demonstrated a significant increment in neuromuscular drive (i.e. tidal volume (V(T))/inspiratory time (T(I)); 0.46 +/- 0.06 to 0.91 +/- 0.15 and 0.48 +/- 0.06 to 0.91 +/- 0.12 l s-1 for Y and O, respectively) with a small (but also significant) change in central timing (T(I)/total ventilation time (T(tot)); 0.38 +/- 0.02 to 0.41 +/- 0.02 and 0.42 +/- 0.02 to 0.45 +/- 0.02 for Y and O, respectively). Oxygen sensitivity was assessed using Weil's equation, and gave a hyperbolic factor (A) of 282 +/- 75 and 317 +/- 72, and using the linear equation: change in expiratory minute volume (DeltaV.(E))/change in arterial O(2) saturation (DeltaS(a,O(2))) which gave -1.17 +/- 0.57 and -1.17 +/- 0.42 l min-1 %-1 (n.s.) for Y and O, respectively. After 20 min of sustained isocapnic hypoxia, ventilation declined to 14.29 +/- 1.92 and 16.85 +/- 2.34 l min-1 for Y and O, respectively (n.s.). The acute response to hypoxia was characterised by similar time constants (16.0 +/- 5.4 and 18.5 +/- 6.7 s) and time delays (4.8 +/- 2.1 and 4.6 +/- 1.9 s) for Y and O, respectively. Thus, the dynamic ventilatory response to acute isocapnic hypoxia is maintained into the eighth decade in a group of habitually active elderly men. Experimental Physiology (2001) 86.1, 117-126.


Asunto(s)
Envejecimiento/fisiología , Hipoxia/fisiopatología , Respiración , Enfermedad Aguda , Adulto , Anciano , Arterias , Humanos , Masculino , Sistema Nervioso/fisiopatología , Oxígeno/sangre , Músculos Respiratorios/inervación , Músculos Respiratorios/fisiopatología , Volumen de Ventilación Pulmonar
6.
Clin Biochem ; 34(1): 23-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11239511

RESUMEN

OBJECTIVES: Concerns have been raised over the possibility of transmission of porcine endogenous retrovirus (PERV) to porcine xenograft recipients. METHODS: To help assess this risk, diagnostic assays capable of detection of an active, latent or cleared PERV infection, and the presence of pig cell microchimerism have been developed by a number of groups. Retrospective studies of patients exposed to living pig tissues have been performed using these assays to look for evidence of cross species transmission. RESULTS: To date no evidence of PERV infection has been found in studies of humans exposed to pig tissues, despite evidence of long lived microchimerism. CONCLUSIONS: These data suggest that PERV infection has not occurred in a clinical setting. However, as infection has been seen in a small animal model further investigation of the risk from PERV is warranted.


Asunto(s)
Química Clínica/métodos , ADN Viral/análisis , Infecciones por Retroviridae/diagnóstico , Infecciones por Retroviridae/transmisión , Retroviridae/metabolismo , Trasplante Heterólogo/efectos adversos , Animales , Humanos , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Porcinos
7.
Prev Med ; 29(6 Pt 1): 571-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10600439

RESUMEN

BACKGROUND: Contact with family physicians by older adults may be linked to their physical fitness in addition to other health, behavioral, and sociodemographic determinants. We studied a stratified random sample of urban community-dwelling elderly patients in London, Ontario, Canada, to describe the interaction of physical fitness measures and a number of health and lifestyle behaviors and sociodemographic outcomes with family physician contact over 1 year. We hypothesized that physician contact would be associated with lower indices of physical fitness and that association would be similar to other known determinants of physician utilization. METHODS: Three hundred seventy-five noninstitutionalized elderly men (N = 185) and women (N = 190) ages 55 to 84 years were recruited from the municipal tax assessment list for the city of London (population 280,000). Four categories of independent variables were selected to reflect common determinants of health (physical fitness, self-reported and clinically measured health, lifestyle behaviors, and sociodemographics). The association between these categories of variables and self-reported contact with family physicians and a variety of health professionals was determined for the year prior to the study. RESULTS: Forty-six percent of the subjects had at least one physician contact in the month prior to the study and 79% within the previous year. None of the other health professions (including nursing, chiropractic, physiotherapy, homemaking, and dentistry) were contacted more than once in the previous year. Lifestyle and sociodemographic variables including activity habits, smoking, income, marital status, and education were not associated with physician contact, whereas poor self-reported cardiovascular health and use of cardiovascular and pulmonary medications were associated with physician contact. Interestingly, physical fitness variables including maximal aerobic capacity, grip strength, and hip flexibility were not associated with physician contact. CONCLUSIONS: The absence of an association among physical fitness, lifestyle, and sociodemographic variables and physician contact was not anticipated and may be due to the selection of individuals who were independent, active community dwellers. It may be that most of the physician contact in this relatively healthy and physically fit sample was preventive in nature, for example, monitoring common chronic disease states in the elderly including cardiovascular and pulmonary disease. This paper reports baseline data from a longitudinal study of the interaction between physical fitness and health outcomes in groups of older community-dwelling individuals. As this group ages further, it would be interesting to determine the use of the health care system in relation to their changing functional and health status. In particular, do chronic health conditions such as cardiovascular disease, which increase in prevalence with age, become modified through maintenance of physical fitness and does this impact on health service use?


Asunto(s)
Medicina Familiar y Comunitaria/estadística & datos numéricos , Servicios de Salud/estadística & datos numéricos , Aptitud Física , Anciano , Anciano de 80 o más Años , Femenino , Estado de Salud , Humanos , Análisis de los Mínimos Cuadrados , Estilo de Vida , Masculino , Persona de Mediana Edad , Ontario , Factores Socioeconómicos
8.
Exp Physiol ; 84(1): 79-91, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10081709

RESUMEN

This study examined the effect of the phenylalkylamine calcium channel blocker verapamil, on resting left ventricular (LV) function and O2 uptake rate (VO2) during exercise at maximal and submaximal work rates. Nine older hypertensive (71 years; OH), 10 older sedentary normotensive (69 years; OS), 10 older active (71 years; OA) and 10 young (24 years; Y) individuals volunteered. Studies were completed in the control condition and 4-6 h following 240 mg verapamil SR per os. Resting LV systolic (fractional shortening; FS) and diastolic (early: late (E/A) flow velocity ratio and isovolumic relaxation time (IVRT) were measured by Doppler echocardiography. Maximal oxygen uptake (VO2,max) and, on subsequent test days, four transitions to and from a 6 min square wave exercise perturbation at a sub-anaerobic threshold intensity of 40 W (OH, OS, OA) or 100 W (Y) for determination of VO2 kinetics were performed on a cycle ergometer. Breath-by-breath VO2 transients were fitted with a monoexponential equation, starting at phase 2 of the response, while heart rate (HR) was fitted from phase 1, for the determination of the time constant of VO2 (tau VO2) and HR (tau HR). Baseline left ventricular FS was significantly greater in the OS (32%), OA (34%) and Y (34%) than in the OH (23%) groups, while E/A was significantly greater in the OA (1.16) and Y (2.34) than in the OH (0.9) and OS (0.82) groups (P < 0.05). Baseline VO2,max was higher and tau VO2 faster in the young (41.4 ml kg-1 min-1; 25.2 s) than in the older groups and in the OA (28.8 ml kg-1 min-1; 44.3 s) than in both OH (20.8 ml kg-1 min-1; 71.3 s) and OS (22.0 ml kg-1 min-1; 59.5 s) groups (P < 0.05). Heart rate kinetics showed similar differences to VO2 kinetics among the groups. After verapamil, no significant changes in FS, E/A or IVRT were observed in the OA and Y groups. In the OH group, FS (32%) and E/A (1.15) increased while IVRT decreased significantly (from 0.103 to 0.07; P < 0.05). In the OS group, only E/A increased significantly (0.82 to 1.0; P < 0.05). None of the exercise variables (VO2,max, tau VO2 or tau HR) were altered for the OA or Y groups. VO2,max increased (from 20.8 to 22.8 ml kg-1 min-1) in the OH and (from 22.0 to 24.1 ml kg-1 min-1) in the OS (P < 0.05). tau VO2 was accelerated from 71.3 to 49.2 s in the OH group and from 59.5 to 48.2 s in the OS group (P < 0.05). These results suggest that VO2 responses at maximal and submaximal work rates may be dependent upon the initial cardiac pump function of the study population.


Asunto(s)
Envejecimiento/metabolismo , Ejercicio Físico/fisiología , Gases/metabolismo , Hipertensión/metabolismo , Adulto , Anciano , Transporte Biológico/fisiología , Bloqueadores de los Canales de Calcio/uso terapéutico , Ecocardiografía Doppler , Femenino , Corazón/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Hemodinámica/fisiología , Humanos , Hipertensión/diagnóstico por imagen , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Masculino , Valores de Referencia , Verapamilo/uso terapéutico
9.
Can J Appl Physiol ; 24(1): 28-40, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9916179

RESUMEN

The interplay of cardiovascular and cellular oxygen uptake determinants of aerobic performance and the system adaptations to training in different population samples are examined in order to describe the limitation. With VO2max, a central limitation following myocardial infarction and ageing is modified with training. Peripheral adaptations occur and stroke volume may be increased primarily through improved diastolic filling. In submaximal perturbations, control of the increase in O2 uptake at exercise onset (O2 kinetics) is most often under peripheral metabolic control, but in exceptions may also be limited by central factors. In young and old the peripheral machinery is matched to the growth (puberty) and loss (ageing) of muscle mass. Cardiac stroke volume capacity may adjust following the changes in muscle mass. Submaximal endurance is closely influenced by the anaerobic threshold (theta(an)) and peripheral factors of oxidative metabolism. Relative to VO2max, the theta(an) is low in children and high in older adults, perhaps reflecting a slow time course in full development and loss of peripheral adaptations. Remarkable increases in endurance performance are related to relatively small changes in the maximal capacity and the relative intensity of performance.


Asunto(s)
Envejecimiento/fisiología , Fenómenos Fisiológicos Cardiovasculares , Consumo de Oxígeno/fisiología , Educación y Entrenamiento Físico , Resistencia Física/fisiología , Adaptación Fisiológica , Umbral Anaerobio , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo , Infarto del Miocardio/rehabilitación , Volumen Sistólico/fisiología
10.
Breast ; 8(4): 188-90, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14731438

RESUMEN

Pure invasive lobular carcinoma is more difficult to diagnose clinically and mammographically than other invasive breast carcinomas. Our objective was to document the ultrasound appearances of pure invasive lobular carcinoma, to determine whether there were any specific features when compared to similar cases of invasive ductal carcinoma, and to compare the sensitivity of ultrasound with mammography in the diagnosis of invasive lobular carcinoma. We report on 23 cases of invasive lobular carcinoma who were matched for age and presentation with cases of invasive ductal carcinoma. High frequency ultrasound detected lesions in 22 cases of invasive lobular carcinoma and all had features highly suggestive of malignancy. Twenty-one of 23 cases of invasive ductal carcinoma also had malignant features. At mammography, six cases of invasive lobular carcinoma were not detected. Ultrasound is as specific for identifying invasive lobular carcinoma as it is for invasive ductal carcinoma. Ultrasound was more sensitive than mammography for diagnosing invasive lobular carcinoma.

11.
Cardiovasc Res ; 38(3): 814-21, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9747450

RESUMEN

OBJECTIVE: We have attempted to demonstrate the induction of inducible nitric oxide synthase in human vascular tissue and define the capacity of different cytokines to induce this enzyme. METHODS: Segments of human arteries were stimulated with lipopolysaccharide (10 micrograms/ml), interleukin-1 beta (5 U/ml), tumor necrosis factor-alpha (10 U/ml), and interferon-gamma (200 U/ml). Cytokines were either used alone or in certain combinations, as well as in the presence of L-NG-monomethyl-arginine (100 mumol/l) or cycloheximide (1 mumol/l). Induction was assessed by measurement of mRNA expression, immunocytochemical localisation of the expressed protein, nitric oxide synthase activity and levels of nitrite, a product of nitric oxide formation. RESULTS: PCR analysis showed the presence of mRNA for iNOS in stimulated samples which could be inhibited by cycloheximide. There was positive staining with an antibody against human iNOS in the media of stimulated vessel segments. Stimulated segments were also shown to contain Ca(2+)-independent nitric oxide synthase activity. The cytokines and lipopolysaccharide together gave a significant rise in levels of nitrite in the medium after 36 and 48 h, which was inhibited by L-NG-monomethyl-arginine and cycloheximide. Only interferon-gamma incubated alone was capable of increasing nitrite levels. This effect was enhanced by co-incubation with either interleukin-1 beta, tumor necrosis factor-alpha or lipopolysaccharide. CONCLUSION: We have shown that increased production of nitrite by human vascular tissue in response to cytokines is associated with induction of iNOS as shown at the molecular and protein levels, and further supported by the presence of increased Ca(2+)-independent nitric oxide synthase activity following cytokine stimulation.


Asunto(s)
Citocinas/metabolismo , Músculo Liso Vascular/enzimología , Óxido Nítrico Sintasa/metabolismo , Cicloheximida/farmacología , Sinergismo Farmacológico , Inducción Enzimática , Humanos , Inmunohistoquímica , Técnicas In Vitro , Interferón gamma/farmacología , Interleucina-1/farmacología , Lipopolisacáridos/farmacología , Músculo Liso Vascular/química , Óxido Nítrico Sintasa/análisis , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Nitritos/análisis , Reacción en Cadena de la Polimerasa , Inhibidores de la Síntesis de la Proteína/farmacología , ARN Mensajero/análisis , Estimulación Química , Factor de Necrosis Tumoral alfa/farmacología , omega-N-Metilarginina/farmacología
12.
J Appl Physiol (1985) ; 82(1): 63-9, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9029199

RESUMEN

The relationships between muscle capillarization, estimated O2 diffusion distance from capillary to mitochondria, and O2 uptake (VO2) kinetics were studied in 11 young (mean age, 25.9 yr) and 9 old (mean age, 66.0 yr) adults. VO2 kinetics were determined by calculating the time constants (tau) for the phase 2 VO2 adjustment to and recovery from the average of 12 repeats of a 6-min, moderate-intensity plantar flexion exercise. Muscle capillarization was determined from cross sections of biopsy material taken from lateral gastrocnemius. Young and old groups had similar VO2 kinetics (tau VO2-on = 44 vs. 48 s; tau VO2-off = 33 vs. 44 s, for young and old, respectively), muscle capillarization, and estimated O2 diffusion distances. Muscle capillarization, expressed as capillary density or average number of capillary contacts per fiber/average fiber area, and the estimates of diffusion distance were significantly correlated to VO2-off kinetics in the young (r = -0.68 to -0.83; P < 0.05). We conclude that 1) capillarization and VO2 kinetics during exercise of a muscle group accustomed to everyday activity (e.g., walking) are well maintained in old individuals, and 2) in the young, recovery of VO2 after exercise is faster, with a greater capillary supply over a given muscle fiber area or shorter O2 diffusion distances.


Asunto(s)
Envejecimiento/metabolismo , Músculos/metabolismo , Oxígeno/metabolismo , Adulto , Anciano , Capilares/metabolismo , Femenino , Humanos , Cinética , Masculino , Persona de Mediana Edad , Músculos/irrigación sanguínea
13.
Transplantation ; 57(9): 1333-7, 1994 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-8184471

RESUMEN

The observations of 2 types of CD4+ T cells (Th1 and Th2), which can be distinguished by their different cytokine profiles, has led to the possibility that analysis of cytokine profiles produced locally within transplanted allografts could be predictive of rejection or acceptance of that graft. We have investigated the expression of IL-2 and TNF beta (Th1 type cytokines), IL-4 and IL-10 (Th2 type cytokines), and the proinflammatory cytokines TNF alpha and IL-1 beta in sequential endomyocardial biopsies collected from 12 cardiac transplant recipients during the first 4 months after transplantation, by the analysis of RNA extracted from each biopsy by reverse transcriptase-polymerase chain reaction. The results obtained were compared with histopathological and clinical indicators of rejection. IL-2 was found in all severe (grade 3), in 57% of moderate (grade 2), in 21% of mild (grade 1) rejection, and in only 1 nonrejection (subsequently progressing to grade 3), where rejection was classified by routine histology. IL-4 and IL-10 were absent from grade 3 rejection, but present in 24% (IL-4) and in 17% (IL-10) of mild rejection and in a single nonrejecting biopsy, respectively. IL-4 was found in 2 cases of moderate rejection, and IL-10 in 1 case of moderate rejection. Statistical analysis showed that the presence of IL-2 positively correlated with both mild and moderate rejection, while IL-4 correlated with mild rejection (P < or = 0.05). IL-1 beta, TNF alpha, and TNF beta were found in both rejecting and nonrejecting biopsies, with no significant differences between the histological grades. Our results suggest that in the human situation, IL-2 and IL-4 may indeed be important in the modulation of rejection.


Asunto(s)
Citocinas/biosíntesis , Trasplante de Corazón/inmunología , Secuencia de Bases , Biomarcadores , Citocinas/genética , Cartilla de ADN/química , Electroforesis en Gel de Agar , Expresión Génica , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/inmunología , Supervivencia de Injerto , Trasplante de Corazón/patología , Humanos , Datos de Secuencia Molecular , Miocardio/inmunología , Miocardio/patología , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , Trasplante Homólogo
14.
Med Sci Sports Exerc ; 26(4): 440-6, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8201899

RESUMEN

The purpose was to characterize gas exchange kinetics following the on-transient of exercise in men aged 30-80 yr. Forty-six men completed square wave exercise tests from loadless cycling to subventilatory threshold (V(E)T) work rates with gas exchange measured breath-by-breath. Signal averaged data were fit with a monoexponential equation to derive time constants (tau) for gas exchange and ventilation (tau VO2, tau VCO2, tau VE) and heart rate (tau HR). There was a significant slowing of ventilation and gas exchange kinetics across age with linear regression yielding an increase of 0.67 s.yr-1 for tau VO2 (39 s in young to 61 s in old), 0.57 s.yr-1 for tau VCO2, and 0.65 s.yr-1 for tau VE, whereas tau HR (44 to 41 s) was not changed significantly. The slowed VO2 kinetics with age may reflect limitations in muscle blood flow or in control of the rate of oxidative metabolism. The less marked slowing of tau VCO2 compared with tau VO2 across age may reflect reduced CO2 storage capacity with loss of muscle tissue. The tau VE change across age was similar to that for tau VCO2 (tau VE/tau VCO2 unchanged). The present study demonstrated marked age-related slowing of gas exchange dynamics at exercise onset.


Asunto(s)
Envejecimiento/fisiología , Esfuerzo Físico/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Dióxido de Carbono/análisis , Prueba de Esfuerzo , Frecuencia Cardíaca/fisiología , Humanos , Cinética , Modelos Lineales , Masculino , Persona de Mediana Edad , Oxígeno/análisis , Consumo de Oxígeno/fisiología , Respiración/fisiología , Volumen de Ventilación Pulmonar/fisiología , Factores de Tiempo
15.
Med Sci Sports Exerc ; 26(4): 447-52, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8201900

RESUMEN

The kinetics of gas exchange at the on-transient of exercise are appreciably slowed in older individuals. Eight older men (72 yr) completed 6 months of aerobic cycle training. Ventilation and gas exchange kinetics were determined at the onset of a below threshold (ventilatory threshold, V(E)T) square wave exercise function and compared with control values (N = 4, age 70 yr). Gas exchange data were measured breath-by-breath and signal averaged data were fit with a monoexponential function to determine the time constants (tau). The training group showed significant increases in VO2max (20%) and VO2 at V(E)T (21%). The tau for oxygen uptake kinetics decreased significantly (62.2 +/- 15.5 to 31.9 +/- 7.0 s). The tau VCO2 (70.9 +/- 10.9 to 43.8 +/- 11.4 s) and tau VE (89.2 +/- 18.0 to 50.4 +/- 11.3) also were significantly faster posttraining; however, tau HR (38.1 +/- 20.5 to 28.6 +/- 7.2) was not significantly altered. Thus, with a vigorous training program, the kinetics of gas exchange of older individuals were faster, and approached values reported in fit young subjects.


Asunto(s)
Ejercicio Físico/fisiología , Resistencia Física/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Anciano , Dióxido de Carbono/análisis , Prueba de Esfuerzo , Frecuencia Cardíaca/fisiología , Humanos , Cinética , Modelos Lineales , Masculino , Oxígeno/análisis , Consumo de Oxígeno/fisiología , Educación y Entrenamiento Físico , Respiración/fisiología , Volumen de Ventilación Pulmonar/fisiología
16.
Am J Respir Crit Care Med ; 149(2 Pt 1): 408-15, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8306038

RESUMEN

This study examines the relationship between minute ventilation (VE) and carbon dioxide production (VCO2) during exercise in men (n = 128) and women (n = 96), 55 to 86 yr of age. The means for the slopes of VE-VCO2 (delta VE/delta VCO2), examined for graded exercise below the ventilation threshold (TVE), increased significantly for men (p < 0.0001), from 25.0 +/- 0.7 (SEM) at mean age 58 (55 to 59) yr to 32.2 +/- 1.8 at mean age 83 (80 to 86) yr, but did not change for women (p = 0.0812), from 22.3 +/- 0.9 at mean age 58 (56-59) yr to 24.2 +/- 2.4 at mean age 79 (75 to 85) yr. A correlation that was significantly greater than zero was found between delta VE/delta VCO2 and age. The increase in delta VE/delta VCO2 was 0.29/yr for men (r = 0.47, p < 0.001) and 0.20/yr for women (r = 0.28, p = 0.0051). In both cases, the explained variance was small (men = 22%; women = 8%). VE, tidal volume (VT), and breathing frequency (fb) were examined at VCO2 = 1.0 L/min, the highest intensity that most older men and women could exercise without exceeding TVE. VE was significantly higher by 14% in men 80 to 86 yr of age (38.2 +/- 1.4 L/min) compared with men 55 to 59 yr of age (33.5 +/- 0.8), whereas there were no differences in VE for the women.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Envejecimiento/fisiología , Dióxido de Carbono/fisiología , Ejercicio Físico/fisiología , Respiración/fisiología , Anciano , Anciano de 80 o más Años , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intercambio Gaseoso Pulmonar/fisiología , Pruebas de Función Respiratoria , Fumar/fisiopatología
17.
Br J Radiol ; 67(793): 1-10, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8298861

RESUMEN

Preliminary results with the first commercially available digital display system to be installed in a British radiology department were published in 1989: these consisted of data from observer performance studies of digitized images displayed using a 1024-line monitor, showing a single pathological feature--subperiosteal resorption in renal osteodystrophy. Further experiments have now been conducted with the successor to this equipment, a 1280-line digital display system. Formal observer performance studies were undertaken for four pathological conditions, and the results show statistically significant differences in performance between the digitized displayed images and those on film. The display system was not considered to be good enough for the task of primary radiological diagnosis of subtle lesions; findings support the conclusion that careful, objective clinical evaluation of digital display systems is important before they are introduced into clinical use.


Asunto(s)
Resorción Ósea/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Neumonía por Pneumocystis/diagnóstico por imagen , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Fracturas Craneales/diagnóstico por imagen , Estudios de Evaluación como Asunto , Femenino , Mano/diagnóstico por imagen , Humanos , Mamografía , Cráneo/diagnóstico por imagen
18.
Respir Physiol ; 91(1): 43-56, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8441870

RESUMEN

The objective of this study was to model the dynamics of, and interrelationships among, gas exchange, ventilation, and heart rate responses to sinusoidal forcing in young and elderly women. Nineteen females, 22-28 years (n = 10) and 62-73 years (n = 9) volunteered for the study. All experiments were conducted at work rates below the ventilatory threshold (TVE). A sine wave test consisted of 4 min of cycling (60 rpm) at a work rate equal to the mean of the limits of sinusoid (60% TVE) followed by 16-20 min of a sinusoidally varying work rate (30-90% of TVE) and ending with 4 min of cycling at 60% TVE. The periods were 0.75, 1.0, 1.5, 3.0, 6.0, 10.0 min, assigned randomly. The averaged data were used to determine amplitude and phase lag of the sinusoidal response of VO2, VCO2, VE, fH, PETCO2, and PETO2. Bode plots demonstrated that the dynamics of the cardiorespiratory responses were all well-described by a first-order exponential equation with a delay for both young and elderly subjects. The time constants were much longer in the elderly. Nevertheless, there appeared to be a strong link between the relative slowing of the four components of the gas transport system (VO2, VCO2, VE, and fH). This may suggest one single factor is reflected in the slowing of all components in older subjects.


Asunto(s)
Envejecimiento/fisiología , Ejercicio Físico/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Adulto , Anciano , Transporte Biológico/fisiología , Dióxido de Carbono/sangre , Femenino , Frecuencia Cardíaca , Humanos , Pulmón/fisiología , Persona de Mediana Edad , Modelos Biológicos , Oxígeno/sangre
19.
J Gerontol ; 47(2): M40-4, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1538064

RESUMEN

In a random cross-sectional study in London, Canada, forced expiratory volume in 1 second (FeV1.0), height, and demispan (fingerweb to central sternal notch) were measured on 182 men and 212 women of mean ages 70.4 (SD 8.5) and 71.3 (8.2). The mean FeV1.0 for men was 2.55 (0.66) l, and for women 1.80 (0.48) l and declined 29 ml.year-1 and 25 ml.year-1, respectively. The mean FeV1.0 standardized for measured height and calculated height for men was 2.54 (0.61) l and 2.55 (0.62) l in men, and 1.80 (0.46) l and 1.79 (0.45) l in women. There was no significant difference between the two methods of standardization, and the relationship of height to demispan in this independent elderly population was constant across age for both men (2.16) and women (2.17). Linear and proportional regression coefficients to predict FeV1.0 from height and demispan have been generated for this random sample aged 55 to 86 years.


Asunto(s)
Estatura , Volumen Espiratorio Forzado , Mano/anatomía & histología , Anciano , Anciano de 80 o más Años , Antropometría , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ontario , Valores de Referencia , Fumar/fisiopatología
20.
Clin Radiol ; 44(4): 268-70, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1835685

RESUMEN

Bone scanning is the most frequent type of radionuclide examination performed. We present a case of reduced uptake on a bone scan thought to be due to etidronate therapy. Other causes of this phenomenon are reviewed.


Asunto(s)
Huesos/metabolismo , Ácido Etidrónico/metabolismo , Medronato de Tecnecio Tc 99m , Anciano , Dolor de Espalda/diagnóstico por imagen , Huesos/diagnóstico por imagen , Huesos/efectos de los fármacos , Ácido Etidrónico/efectos adversos , Ácido Etidrónico/uso terapéutico , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Cintigrafía , Medronato de Tecnecio Tc 99m/metabolismo
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