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1.
J Clin Densitom ; 19(4): 515-521, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27102659

RESUMEN

While analyzing dual-energy X-ray absorptiometry (DXA) examinations, we observed that, on occasion, the Ward region of interest (ROI) was positioned either unexpectedly or differently between successive examinations. When this occurred, it appeared to be either a marker of a compromised examination or of incident disease. This prompted a systematic inquiry. It became apparent that, while in general seeking the region of least areal density, the Ward ROI is positioned differently by the machines available to us from 2 particular manufacturers (General Electric Co. and Hologic Inc.). Three reviews were thus undertaken: (1) a prospective systematic examination of 200 unselected consecutive DXA examinations made with a General Electric Co. machine, 80 having had follow-up examinations and 245 made with a Hologic Inc. device; (2) a prospective systematic examination of 625 consecutive, unselected DXA examinations that were repeat examinations; and (3) a retrospective examination of a file of 86 cases collected for pedagogical purposes, predominantly made with a Hologic Inc. device. The commonest cause of an unusual position of the Ward area was compromised patient positioning or change in body habitus. Changes between examinations were, in addition if less often, apt to reflect physiological change or disease. Unusual positioning or a change in position of the Ward ROI is easily observed. It does not occur frequently, but, when it does, it may be useful in directing attention to either technical factors or incidental diseases. Observation of the position of the Ward ROI may thus be a quality assurance, and occasionally a diagnostic, tool.


Asunto(s)
Absorciometría de Fotón/instrumentación , Absorciometría de Fotón/métodos , Fémur/diagnóstico por imagen , Posicionamiento del Paciente , Absorciometría de Fotón/normas , Peso Corporal , Humanos , Osteoporosis/diagnóstico por imagen , Garantía de la Calidad de Atención de Salud
2.
Transplantation ; 91(3): 373-8, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21258272

RESUMEN

BACKGROUND: The effect of islet cell transplantation (ICT) on the progression of diabetic microvascular complications is not well understood. METHODS: We have conducted a prospective, crossover, cohort study comparing ICT with intensive medical therapy on the progression of diabetic nephropathy, retinopathy, and neuropathy. RESULTS: The rate of decline in glomerular filtration rate is slower after ICT than on medical therapy. There was significantly more progression of retinopathy in medically treated patients than post-ICT. There was a nonsignificant trend for improved nerve conduction velocity post-ICT. CONCLUSIONS: ICT is associated with less progression of microvascular complications than intensive medical therapy. Multicenter, randomized trials are needed to further study the role of ICT in slowing the progression of diabetic complications.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/terapia , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/prevención & control , Progresión de la Enfermedad , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos , Adulto , Estudios de Cohortes , Estudios Cruzados , Angiopatías Diabéticas/fisiopatología , Nefropatías Diabéticas/epidemiología , Neuropatías Diabéticas/epidemiología , Retinopatía Diabética/epidemiología , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Incidencia , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
4.
Transplantation ; 84(1): 17-22, 2007 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-17627232

RESUMEN

BACKGROUND: The effect of islet cell transplantation (ICT) on renal function in type 1 diabetes is uncertain and some recent studies report a significant decline in estimated glomerular filtration rate (GFR) and worsening of albuminuria. METHODS: We are conducting a prospective crossover study comparing medical treatment with islet transplantation on the progression of diabetic complications, including renal function. The primary endpoint is change in GFR measured by Tc-diethylenetriaminepentaacetate with secondary endpoints including estimated GFR and albumin excretion. RESULTS: We have followed 21 patients after islet transplantation a median of 29 months (range 13-45) and compared their results with medically treated patients followed a median 29.5 months (range 13-56). There is no difference in the rate of decline in measured GFR between medically treated patients (-0.35+/-0.89; 95% CI: -0.57 to -0.13 mL/min/month/1.73 m) and those after ICT (-0.31+/-1.18; 95% CI: -0.61 to -0.01) and neither is significantly different from that expected for the general population. The rate of decline in our estimated GFR results is lower than that reported in other studies and we did not find any worsening of albuminuria. CONCLUSIONS: We do not find evidence of worsening of renal function after islet transplantation compared with medically treated patients.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/fisiopatología , Hipoglucemiantes/uso terapéutico , Trasplante de Islotes Pancreáticos , Adulto , Anciano , Albuminuria/fisiopatología , Glucemia/metabolismo , Estudios de Cohortes , Estudios Cruzados , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/orina , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
J Appl Physiol (1985) ; 103(3): 917-25, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17585046

RESUMEN

Lymphoscintigraphy was used to measure lymphatic function at rest and during exercise in breast cancer survivors with lymphedema (BCRL, n = 10), breast cancer survivors (BC, n = 10), and controls (Cont, n = 10). After injection of (99m)Tc-antimony colloid to the hands, subjects rested or performed 12 repeated sets of arm cranking for 2.5 min at 0.6 W/kg followed by 2.5 min of rest. One-minute spot views were taken with a gamma-radiation camera immediately postinjection and every 10 min over 60 min to calculate clearance rate. As well, an upper body scan was taken at 65 min postinjection to measure radiopharmaceutical uptake in the axilla (Ax) and forearm (Fore). All groups displayed similar increases in clearance rate with exercise (P = 0.000). Ax significantly increased with exercise in Cont only [Cont: (mean +/- SD) 4.9 +/- 2.6 vs. 7.9 +/- 4.2%, P = 0.000; BCRL: 1.4 +/- 1.2 vs. 1.7 +/- 2.1%, P = 0.531; BC: 3.9 +/- 3.4 vs. 5.2 +/- 3.2%, P = 0.130], whereas Fore, indicating dermal backflow, significantly increased in BCRL only (BCRL: 2.4 +/- 0.87 vs. 4.4 +/- 2.0%, P = 0.004; BC: 1.1 +/- 0.25 vs. 1.1 +/- 0.31%, P = 0.784; Cont: 0.93 +/- 0.26 vs. 1.0 +/- 0.20%, P = 0.296). The results indicate that, in women with BCRL, exercise causes radiopharmaceuticals to clear from the hand at the same rate as BC and Cont, but, instead of reaching the axilla, a greater amount of activity gets trapped in the dermis of the forearm. BC, meanwhile, have similar lymphatic function as Cont; however, there is a highly variable response that may suggest that some BC subjects may be at risk for developing lymphedema.


Asunto(s)
Ejercicio Físico/fisiología , Vasos Linfáticos/fisiopatología , Linfedema/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Extremidad Superior/fisiopatología , Anciano , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Vasos Linfáticos/diagnóstico por imagen , Linfedema/diagnóstico por imagen , Linfedema/etiología , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Extremidad Superior/diagnóstico por imagen
6.
Nucl Med Commun ; 28(7): 521-7, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17538392

RESUMEN

Whole-body bone scintigraphy (bone scan) using a (99m)Tc-labelled pharmaceutical is one of the most commonly performed radionuclide examinations. In the normal patient, both the osseous components of the skeletal system as well as the kidneys and bladder are visualized. A superscan is defined as a bone scan which demonstrates markedly increased skeletal radioisotope uptake relative to soft tissues, in association with absent or faint genito-urinary tract activity. While a superscan is relatively uncommon, its recognition is important, as it is associated with a number of important underlying diseases. The purpose of this review article is to describe the causes and variable features of a superscan and depict patterns which may aid in defining the underlying cause for the scan. In addition, we will discuss other investigations that may help further to identify the underlying disease in such cases.


Asunto(s)
Enfermedades Óseas/diagnóstico por imagen , Aumento de la Imagen/métodos , Tecnecio , Imagen de Cuerpo Entero/métodos , Humanos , Cintigrafía , Radiofármacos
7.
Lymphat Res Biol ; 4(3): 159-65, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17034296

RESUMEN

BACKGROUND: Little is known about the acute effects of exercise on the lymphatic system. Thus, the purpose was to determine the effect of low versus high intensity upper body exercise on lymphatic function in healthy females. METHODS AND RESULTS: On separate days, eight females performed either HI: 12 repeated sets of arm cranking for 2.5 min at 0.6 W.kg-1, followed by 2.5 min of rest; or LO: 12 repeated sets of arm cranking for 2.5 min at 0.3 W.kg-1, followed by 2.5 min of rest. One min spot views were taken with a gamma-radiation camera immediately after injection of 99mTc-antimony colloid and every 10 min thereafter to measure the clearance rate (CR) from the first and fourth finger-web of each hand. Radiopharmaceutical uptake in the axillary regions (AX) at 65 min postinjection was also measured. Clearance from the injection sites was linear and expressed as a slope (% administered activity.min-1). HI resulted in significantly greater CR (-0.24%.min-1+/-0.06) than LO (-0.19%.min-1+/-0.05; p=0.003). A similar trend was seen in AX (HI: 6.3%+/-1.6, LO: 4.8%+/-1.1, p=0.004). CONCLUSIONS: The results indicate that an arm cranking protocol of higher intensity is more effective in promoting lymphatic clearance from the hand. Further, the high intensity protocol may be useful in the functional evaluation of the lymphatic system in breast cancer survivors and warrants further investigation.


Asunto(s)
Ejercicio Físico/fisiología , Sistema Linfático/fisiología , Linfocintigrafia , Adolescente , Adulto , Antimonio/farmacocinética , Brazo/fisiología , Axila/diagnóstico por imagen , Axila/fisiología , Prueba de Esfuerzo , Femenino , Mano/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/fisiología , Compuestos de Tecnecio/farmacocinética
8.
Sports Med ; 35(6): 461-71, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15974632

RESUMEN

This article summarises the current research on the lymphatic system related to exercise and critically evaluates the implications for exercise performance by breast-cancer survivors. The primary role of the lymphatic system during exercise is to assist in the regulation of tissue volume and pressure by carrying fluid and plasma proteins that have leaked into the interstitial space from tissues back to the cardiovascular system. During steady-state exercise in humans, lymph flow has been shown to increase to levels approximately 2- to 3-fold higher than at rest. Although the lymphatic system does not typically limit exercise performance in the normal population, the function of this system can be impaired in 27-49% of women who have survived breast cancer. Breast cancer-related lymphoedema (BCRL) is a chronic swelling that can occur in the ipsilateral hand or arm of women treated for breast cancer and results in a number of physical and psychological sequelae. Exercise was once believed to be a factor in the development of BCRL as it was thought that the damage to the axillary lymphatics from breast-cancer treatment resulted in a primary obstruction to lymph flow. However, the exact aetiology and pathophysiology of BCRL appears to be multi-factorial and not as simple as a 'stop-cock' effect. Furthermore, recent studies have shown that participating in vigorous, upper-body exercise is not related to an increase in arm volume, which would indicate the development of BCRL. It is still not known, though, how long-term exercise affects lymphatic system function in breast-cancer survivors with and without BCRL.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Ejercicio Físico , Sistema Linfático/fisiopatología , Sobrevivientes , Femenino , Humanos , Sistema Linfático/anatomía & histología , Linfedema/fisiopatología
9.
Lymphat Res Biol ; 3(1): 16-24, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15770082

RESUMEN

BACKGROUND: Currently, there is not a standardized protocol to evaluate lymphatic function in women. Therefore, the purpose of this study was to evaluate the effects of arm crank ergometry (AC) and handgrip contractions (HG) on radiopharmaceutical clearance from the hands of six healthy females. METHODS AND RESULTS: On separate days, subjects performed AC (six repeated bouts of arm cranking for 5 min at 0.6 Watts.kilogram(-1) (W.kg(-1)) followed by 5 min rest) or HG (twelve repeated bouts of 75 contractions in 2.5 min at 50% MVC followed by 2.5 min of rest). HG was done with the right hand only while the left hand served as a control (CON). Prior to the start of exercise, (99m)Tc-antimony colloid was injected into the first and fourth finger-web of each hand, and 1 min spot views were taken immediately after the injection and then again every 10 min over 60 min. Clearance from the injection sites was linear and expressed as a slope (% administered activity.min(-1)). Significantly faster clearance was observed with AC (rt = -0.27 +/- 0.03 %.min(-1); left = -0.29 +/- 0.06 %.min(-1)) compared to both HG (-0.18 +/- 0.03 %.min(-1)) and CON (-0.14 +/- 0.05 %.min(-1); p = 0.000). CONCLUSION: The results indicate that AC may be more effective in promoting lymphatic clearance from the hand and may be a useful protocol to challenge the lymphatic system in breast cancer survivors.


Asunto(s)
Ejercicio Físico/fisiología , Mano/diagnóstico por imagen , Mano/fisiología , Sistema Linfático/fisiología , Adolescente , Adulto , Antimonio , Coloides , Femenino , Humanos , Cintigrafía , Tecnecio
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