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1.
ESMO Open ; 9(1): 102219, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38194881

RESUMEN

BACKGROUND: Despite the prognostic relevance of cachexia in pancreatic cancer, individual body composition has not been routinely integrated into treatment planning. In this multicenter study, we investigated the prognostic value of sarcopenia and myosteatosis automatically extracted from routine computed tomography (CT) scans of patients with advanced pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: We retrospectively analyzed clinical imaging data of 601 patients from three German cancer centers. We applied a deep learning approach to assess sarcopenia by the abdominal muscle-to-bone ratio (MBR) and myosteatosis by the ratio of abdominal inter- and intramuscular fat to muscle volume. In the pooled cohort, univariable and multivariable analyses were carried out to analyze the association between body composition markers and overall survival (OS). We analyzed the relationship between body composition markers and laboratory values during the first year of therapy in a subgroup using linear regression analysis adjusted for age, sex, and American Joint Committee on Cancer (AJCC) stage. RESULTS: Deep learning-derived MBR [hazard ratio (HR) 0.60, 95% confidence interval (CI) 0.47-0.77, P < 0.005] and myosteatosis (HR 3.73, 95% CI 1.66-8.39, P < 0.005) were significantly associated with OS in univariable analysis. In multivariable analysis, MBR (P = 0.019) and myosteatosis (P = 0.02) were associated with OS independent of age, sex, and AJCC stage. In a subgroup, MBR and myosteatosis were associated with albumin and C-reactive protein levels after initiation of therapy. Additionally, MBR was also associated with hemoglobin and total protein levels. CONCLUSIONS: Our work demonstrates that deep learning can be applied across cancer centers to automatically assess sarcopenia and myosteatosis from routine CT scans. We highlight the prognostic role of our proposed markers and show a strong relationship with protein levels, inflammation, and anemia. In clinical practice, automated body composition analysis holds the potential to further personalize cancer treatment.


Asunto(s)
Aprendizaje Profundo , Neoplasias Pancreáticas , Sarcopenia , Humanos , Pronóstico , Sarcopenia/complicaciones , Músculo Esquelético/patología , Estudios Retrospectivos , Composición Corporal , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología
2.
Orthopade ; 49(2): 169-176, 2020 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-31974632

RESUMEN

BACKGROUND: Tissue defects of the trunk and limbs after oncologic surgery and radiation require plastic reconstructive tissue coverage. Depending on the location and size of the wound as well as the interdisciplinary treatment concept, different reconstructive procedures are performed. These range from skin transplantation to local and pedicle flaps, to perforator flaps and free microsurgical tissue transfer. METHODS: The modern "reconstructive ladder" can be regarded as an orientation for the sequence of the reconstructive options. Considering the patient's wishes and risk profile, an individual reconstructive concept must be devised. The best functional and simultaneously safest procedure with the smallest secondary defect is to be chosen. Wound preconditioning via vacuum-assisted closure can precede definitive tissue coverage in order to optimize local conditions. CONCLUSION: Safe tissue coverage can be achieved even in advanced stages of oncologic disease and after extensive surgery by performing wound preconditioning and arteriovenous loop grafting to induce safe de novo recipient vessels for two-stage free tissue transfer. The choice between maximum plastic reconstructive options for a curative approach or limited palliative surgery is to be harmonized and balanced with therapeutic goals and the patient's biologic resources. Preservation and restoration of quality of life and functionality is the plastic surgeon's dictum.


Asunto(s)
Neoplasias , Procedimientos de Cirugía Plástica , Humanos , Calidad de Vida , Trasplante de Piel , Colgajos Quirúrgicos
3.
J Am Coll Cardiol ; 29(4): 791-9, 1997 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9091526

RESUMEN

OBJECTIVES: The purpose of this study was to prove that transient response harmonic imaging could detect normal and abnormal myocardial perfusion in multiple echocardiographic windows with one intravenous injection of microbubbles in humans. BACKGROUND: Myocardial ultrasound contrast can be produced from intravenous perfluorocarbon-exposed sonicated dextrose albumin, and ultrasound can be significantly improved by briefly suspending the interval between frame rates. Whether this contrast can noninvasively quantify myocardial perfusion in humans is unknown. METHODS: In 28 patients, harmonic transient response imaging was used to image the heart in multiple different imaging planes after one intravenous injection of ultrasound contrast agent. Twenty-five of these 28 patients had a repeat injection during dipyridamole stress. In the primary view, the ultrasound transmission rate was one frame per cardiac cycle; in secondary and tertiary views, the transmission rate was once every multiple cardiac cycles. Regional myocardial contrast was visually assessed and quantified off-line. Quantitative rest thallium and dipyridamole stress sestamibi imaging was also performed. RESULTS: Perfusion abnormalities were evident in the secondary and tertiary views only with one frame every multiple cardiac cycles. Regional peak myocardial videointensity (PMVI) correlated closely with regional tracer uptake in individual patients both at rest (r = 0.84) and during stress (r = 0.88). A PMVI ratio (abnormal region divided by the region with highest nuclear uptake) < 0.6 in any view had a 92% sensitivity and a 84% specificity in identifying a regional nuclear perfusion abnormality. CONCLUSIONS: Transient response imaging produces myocardial contrast in multiple views with one intravenous injection of contrast agent and can accurately identify regional myocardial perfusion abnormalities.


Asunto(s)
Medios de Contraste , Ecocardiografía , Fluorocarburos , Corazón/diagnóstico por imagen , Aumento de la Imagen , Adulto , Anciano , Anciano de 80 o más Años , Dipiridamol , Ecocardiografía/métodos , Prueba de Esfuerzo , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sonicación , Tecnecio Tc 99m Sestamibi , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único , Vasodilatadores
4.
Clin Cardiol ; 19(9): 755-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8874998

RESUMEN

Dobutamine stress echocardiography (DSE) has been widely used for the noninvasive diagnosis of obstructive coronary artery disease. The ST-segment elevation during DSE has been reported as an infrequent event, caused by old myocardial infarction and/or critical coronary narrowings. The patient presented here was a 35-year-old man with a recent history of nonexertional chest pain. He had hypercholesterolemia and a history of heavy smoking as risk factors. The patient developed ST-segment elevation with chest pain during 40 mcg/min dobutamine infusion for the stress echocardiographic examination. Subsequent coronary angiograms revealed only mild coronary atherosclerosis. It is speculated that coronary spasm occurred in this patient as a paradoxical response to increased coronary blood flow with dobutamine administration.


Asunto(s)
Angina Pectoris Variable/etiología , Cardiotónicos , Dobutamina , Ecocardiografía/efectos adversos , Adulto , Angina Pectoris Variable/fisiopatología , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Humanos , Masculino
5.
J Am Coll Cardiol ; 27(6): 1497-501, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8626965

RESUMEN

OBJECTIVES: The objectives of this study were to determine whether a new method of ultrasound imaging (transient response imaging) could improve the myocardial contrast after intravenous injections of perfluorocarbon-exposed sonicated dextrose albumin microbubble contrast medium in humans. BACKGROUND: We have shown in animals that very low doses of intravenous contrast medium can produce transient but significantly better myocardial contrast when diagnostic ultrasound pulses are interrupted (delivered only once per cardiac cycle) instead of conventional 25- to 30-Hz frame rate imaging. METHODS: In 14 patients with normal rest wall motion, the peak myocardial contrast produced by transient response imaging was compared with that produced by conventional harmonic ultrasound imaging after injections of low doses (0.0025 to 0.01 ml/kg) of intravenous contrast medium. All studies were performed with second harmonic imaging (2.0 to 2.5 MHz-transmitted frequency). Blood pressure, oxygen saturation, respiratory rate and pulse were monitored before and after each injection. RESULTS: The intravenous contrast medium in the doses given produced no hemodynamic changes and no significant side effects in any patients. Overall, the mean (+/-SD) anterior and posterior myocardial contrast produced was significantly greater with transient response imaging than with conventional harmonic ultrasound imaging (anterior: 37 +/- 20 U transient response imaging vs. 18 +/- 14 U conventional harmonic imaging; posterior: 17 +/- 14 U transient response imaging vs. 5 +/- 5 U conventional; p< 0.01). With the sample size of 14 patients, the study had 80% power to detect a true difference of 18 U for anterior myocardial contrast and 90% power to detect a difference of 12 U for posterior contrast. Visually evident anterior or apical myocardial contrast was observed in 14 of 15 patients with transient response imaging but in only 7 patients with conventional harmonic imaging. Posterior or basal myocardial contrast was evident in 10 patients with transient response imaging but in only 1 patient with conventional harmonic imaging. CONCLUSIONS: Transient response imaging produces significantly better myocardial contrast than conventional harmonic imaging in humans and can be produced safely with minute quantities of intravenous perfluorocarbon.


Asunto(s)
Medios de Contraste , Ecocardiografía/métodos , Fluorocarburos , Albúminas , Medios de Contraste/administración & dosificación , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad
6.
Cathet Cardiovasc Diagn ; 37(2): 178-83, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8808078

RESUMEN

Conduction disturbances in the setting of calcific aortic valve disease have been well documented in the literature. In this report we describe a case of a patient who presented in complete heart block and dyspnea on exertion. Subsequent non-invasive and invasive studies revealed moderate aortic stenosis and regurgitation with preserved left ventricular function. Hemodynamically important physiological pressure waveform changes occurred before and after pacing the ventricles and are highlighted here.


Asunto(s)
Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/fisiopatología , Estimulación Cardíaca Artificial , Bloqueo Cardíaco/fisiopatología , Anciano , Insuficiencia de la Válvula Aórtica/complicaciones , Insuficiencia de la Válvula Aórtica/terapia , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/terapia , Bloqueo Cardíaco/complicaciones , Bloqueo Cardíaco/terapia , Hemodinámica , Humanos , Masculino
7.
Cathet Cardiovasc Diagn ; 35(3): 257-61, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7553836

RESUMEN

We report a case of a patient who presented with sudden cardiac death secondary to a subtotal occlusion of a small non-dominant right coronary system. Catheterization several weeks following the initial episode revealed persistent severe right ventricular dysfunction with moderate hemodynamic compensation. Continued unstable arrhythmogenic potential at this point led to placement of an AICD device. The case highlights the potential hazard and often complacency involved in dealing with benign appearing lesions as this one.


Asunto(s)
Arritmias Cardíacas/etiología , Enfermedad Coronaria/complicaciones , Muerte Súbita Cardíaca/etiología , Disfunción Ventricular Derecha/etiología , Constricción Patológica/complicaciones , Femenino , Humanos , Persona de Mediana Edad
8.
Chest ; 99(2): 504-5, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1989820

RESUMEN

The cause of bleeding in a patient with recurrent massive hemoptysis was not apparent after bronchoscopy and gross examination of the lobectomy specimen. Histologic submission of all major bronchi uncovered dilated, tortuous bronchial arteries just below the bronchial mucosa with sites of both current and healing arterial rupture. This bronchial arterial abnormality is common to several chronic pulmonary diseases, but is rarely diagnosed as a cause of massive hemoptysis. Careful pathologic examination of major bronchi in the setting of hemoptysis of unknown causation is recommended.


Asunto(s)
Arterias Bronquiales/patología , Bronquitis/complicaciones , Hemoptisis/etiología , Anciano , Bronquitis/patología , Enfermedad Crónica , Femenino , Hemoptisis/patología , Humanos , Recurrencia
9.
Mech Ageing Dev ; 14(1-2): 203-9, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6259457

RESUMEN

The activities of glycolytic enzymes were determined in human autoptic temporal lobes from patients with different forms of dementia. For some enzymes (hexokinase, phosphofructokinase and phosphoglycerate mutase) the effect seen in dementia can be regarded as an intensification of the normal ageing affect. For other enzymes (aldolase, phosphoglucose isomerase, triosephosphate isomerase and lactate dehydrogenase) no changes in enzyme activities corresponding to those found in dementia are observed in the normal ageing process. These effects are most pronounced in the non-vascular Alzheimer cases. With the exception of triosephosphate isomerase and lactate dehydrogenase, enzyme activity is also reduced in bronchopneumonia. The effects of dementia and bronchopneumonia on the activities of glycolytic enzymes in human autoptic brain tissue are often difficult to distinguish.


Asunto(s)
Envejecimiento , Encéfalo/enzimología , Demencia/enzimología , Glucólisis , Anciano , Enfermedad de Alzheimer/enzimología , Bronconeumonía/enzimología , Fructosa-Bifosfato Aldolasa/metabolismo , Glucosa-6-Fosfato Isomerasa/metabolismo , Hexoquinasa/metabolismo , Humanos , L-Lactato Deshidrogenasa/metabolismo , Fosfofructoquinasa-1/metabolismo , Fosfoglicerato Mutasa/metabolismo , Triosa-Fosfato Isomerasa/metabolismo
10.
Aktuelle Gerontol ; 10(5): 203, 1980 May.
Artículo en Alemán | MEDLINE | ID: mdl-6106427

RESUMEN

The influence of aging and pre- and post-mortem conditions on the activities of glycolytic enzymes and of the ATPases was determined in samples of autoptic human cerebral cortex and putamen. These results were compared with results obtained from an aging collective of rats (four groups ranging from 20 to 120 weeks of age). The results revealed an interlinked significant age-related increase in soluble hexokinase (HK) and a significant decrease in phosphofructokinase (PFK) activity in human autoptic tissue, whereas no significant age-dependent differences could be observed in rat brain. Subdivision of the cases according to duration of agony and other pre-mortem conditions revealed reduced variance and therefore statistically more significant PFK age-dependence in cases with a short agony. All other cases are not dependent on age. In addition to the pre- and post-mortem effects, the age-dependence of PFK and soluble HK can be clearly demonstrated in human autoptic brain tissue.


Asunto(s)
Envejecimiento , Encéfalo/enzimología , Hexoquinasa/metabolismo , Dolor/enzimología , Fosfofructoquinasa-1/metabolismo , Cambios Post Mortem , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Anciano , Animales , Corteza Cerebral/enzimología , Humanos , Persona de Mediana Edad , Putamen/enzimología , Ratas
12.
J Trauma ; 15(10): 922-5, 1975 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1177341

RESUMEN

A case of room-temperature vulcanizing (RTV) silicone injection of the hand is presented, and principles of management of high-pressure hand injuries are outlined. Early debridement and decompression are urgent in the acute stage of injury. Intermediate stages require adequate coverage and mobilization, and late stages involve reconstructive procedures. As in all high-pressure hand injuries, safety measures and prevention at the industrial level are very important.


Asunto(s)
Traumatismos de los Dedos , Medicina del Trabajo , Silicio/efectos adversos , Adulto , Desbridamiento , Traumatismos de los Dedos/terapia , Humanos , Masculino , Presión , Silicio/administración & dosificación
13.
Aviat Space Environ Med ; 46(5): 671-8, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-1131130

RESUMEN

The purpose of this study was to determine the effects of isometric or isotonic exercise training on post-bedrest +Gz tolerance. Seven male volunteers, 19-22 years, underwent accelerations of +2.1 Gz (740 s), +3.2 Gz (327 s), and +3.8 Gz (312 s) in a selected, randomized order; the ramp to peak acceleration was 1.8 G/min. The centrifugation runs were terminated by loss of central vision (blackout) to a white light with a luminance of 3.15 times 10-5 log candle/cm-2 (0.092 ft-lambert). The study began with a 14-d ambulatory control period, followed by three 14-d bedrest periods (each separated by a 21-d recovery period) and then a final week of recovery. During the ambulatory periods, the subjects exercised on a bicycle ergometer at 50% of their maximal oxygen uptake (max VO2) for 1 h/d. During two of the three bedrest periods, the subjects performed in the supine position one of two routines, either isometric exercise (21% of max leg extension force for 1 min followed by 1-min rest) or isotonic exercise (68% of max VO2) for 0.5 in the morning and afternoon. During the third bedrest period, no exercise was performed. In general +Gz tolerance was reduced by 24% to 35% (p less than or equal to 0.05) after bedrest. Compared with control values, there were significant reductions in average tolerance times after bedrest with no exercise and isotonic exercise at all G levels. With isometric exercise, there was a significant decrease in tolerance at 2.1 Gz but not at 3.2 Gz or 3.8 Gz, even though the latter tolerances were reduced 15.6% and 10.0%, respectively. Both exercise regimens maintained tolerance at levels equal to or above that obtained with no exercise. Compared with control values, average tolerances were lower (p less than or equal to 0.05) after the two recovery periods between the bedrest periods (minus 24% to minus 26% at 3.2 Gz and 3.8 Gz), indicating that 3 weeks of ambulation was not sufficient time for full recovery from the deconditioning induced in this study. A prediction equation was constructed with data from all comparable studies utilizing deconditioned men riding relaxed without protective garments: Tolerance (in seconds) equals minus 334 + (1715/+Gz level). From this equation, the calculated tolerance after bedrest is 13.5 min at 1.5 G, and the point of zero tolerance is 5.1 Gz.


Asunto(s)
Aceleración , Esfuerzo Físico , Descanso , Adaptación Fisiológica , Adulto , Medicina Aeroespacial , Análisis de Varianza , Presión Sanguínea , Temperatura Corporal , Peso Corporal , Dieta , Ambiente Controlado , Frecuencia Cardíaca , Humanos , Masculino , Consumo de Oxígeno , Equilibrio Postural , Presión , Pulso Arterial , Respiración , Factores de Tiempo , Estados Unidos , Visión Ocular
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