RESUMEN
Immediate feedback was given to correct observers' estimates of distance in an experiment in which those estimates were made outdoors at night while observers wore night vision goggles (NVGs). Initially observers made unguided estimates of distances between marked positions in an open field. Those distances ranged from 7.6 m (25 ft) to 64 m (210 ft). Later the same observers made more estimates. After each of these they were told the measured distance between the positions. During this training, the observers' height from the ground plane was either at a standing position or at an elevated position raised 2.3 m (7 ft 7 in) from standing position. After the training--either immediately after, a week later, or at both times--observers made unguided estimates of distance for a second time. These latter estimates of ground distance made with the NVGs were improved. Average improvement of the observers' estimates persisted for at least one week after training. This training can be applied to improve clearance estimates and estimates of hover height for pilots of rotary-wing aircraft.
Asunto(s)
Medicina Aeroespacial , Adaptación a la Oscuridad , Percepción de Distancia , Anteojos , Aviación , Retroalimentación , Femenino , Humanos , Modelos Lineales , Masculino , Análisis y Desempeño de TareasRESUMEN
The medical criteria for inoperability have been difficult to define in patients with lung cancer. Sixty-six patients with non-small cell lung cancer and radiographically resectable lesions were evaluated prospectively in a clinical trial. The patients were considered by cardiac or pulmonary criteria to be high risk for pulmonary resection. If exercise testing revealed a peak oxygen uptake of 15 mL.kg-1.min-1 or greater, the patient was offered surgical treatment. Of the 20 procedures performed, nine were lobectomies, two were bilobectomies, and nine were wedge or segmental resections. All patients were extubated within 24 hours and discharged within 22 days after operation (median time to discharge, 8 days). There were no deaths, and complications occurred in 8 (40%) of the 20 patients. Five patients whose peak oxygen uptake was lower than 15 mL.kg-1.min-1 also underwent surgical intervention; there was one death. Thirty-four patients whose peak oxygen uptake was less than 15 mL.kg-1.min-1 and 7 who declined operation underwent radiation therapy alone (35 patients) or radiation therapy and chemotherapy (6 patients). There were no treatment-related deaths, and the morbidity rate was 12% (5/41). The median duration of survival was 48 +/- 4.3 months for the patients treated surgically and 17 +/- 2.7 months for those treated medically (p = 0.0014). We conclude that a subgroup of patients who would be considered to have inoperable disease by traditional medical criteria can be selected for operation on the basis of oxygen consumption exercise testing. There is a striking survival benefit to an aggressive surgical approach in these patients.
Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias Pulmonares/terapia , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/fisiopatología , Anciano , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/fisiopatología , Terapia Combinada , Prueba de Esfuerzo , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Oxígeno/farmacocinética , Oxígeno/fisiología , Consumo de Oxígeno , Selección de Paciente , Neumonectomía , Complicaciones Posoperatorias/epidemiología , Cuidados Preoperatorios , Estudios Prospectivos , Intercambio Gaseoso Pulmonar , Pruebas de Función Respiratoria , Factores de Riesgo , Tasa de Supervivencia , Resultado del TratamientoAsunto(s)
Enfermedades de la Aorta/diagnóstico por imagen , Ecocardiografía Transesofágica , Fístula/diagnóstico por imagen , Cardiopatías/diagnóstico por imagen , Lesiones Cardíacas/cirugía , Heridas Punzantes/cirugía , Adulto , Enfermedades de la Aorta/etiología , Fístula/etiología , Cardiopatías/etiología , Lesiones Cardíacas/complicaciones , Lesiones Cardíacas/diagnóstico por imagen , Ventrículos Cardíacos , Humanos , Masculino , Heridas Punzantes/complicaciones , Heridas Punzantes/diagnóstico por imagenRESUMEN
P-glycoprotein (Pgp), encoded by the multidrug-resistance gene (MDR1), is an active efflux pump for many structurally diverse lipophilic compounds. Using peroxidase-antiperoxidase immunohistochemistry technique and four anti-Pgp monoclonal antibodies directed against different epitopes of the molecule, we examined the distribution of Pgp in normal human tissues and squamous cell carcinomas of the head and neck. All four antibodies detected Pgp in bronchial cells, mammary ductal epithelium, gallbladder epithelium, epithelia of small and large intestine, bile canaliculi, dermal sweat glands, proximal tubules of kidney, endometrium, trophoblasts, adrenal gland, and capillaries of central nervous system, testis, and papillary dermis. Of the 23 head and neck squamous cell carcinomas, about 60% had detectable Pgp. It is possible that differences noticed between antibodies are due to cross-reactivity to proteins unrelated to MDR1. Care must be taken in interpreting staining results when only one or two monoclonal antibodies are used.
Asunto(s)
Carcinoma de Células Escamosas/química , Proteínas Portadoras/análisis , Neoplasias de Cabeza y Cuello/química , Glicoproteínas de Membrana/análisis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Anticuerpos Monoclonales , Proteínas Portadoras/inmunología , Endotelio Vascular/química , Humanos , Técnicas para Inmunoenzimas , Glicoproteínas de Membrana/inmunología , Proteínas de Neoplasias/análisis , Distribución Tisular , Células Tumorales CultivadasRESUMEN
We have analyzed the expression of the p53 tumor suppressor gene in paraffin-embedded sections of normal and malignant head and neck and lung tumors by immunohistochemistry using the PAb 1801 monoclonal antibody (MAb). The PAb 1801 does not consistently detect its p53 epitope in tissue fixed in 10% buffered formaldehyde. However, the antibody is effective in AMeX-fixed specimens, thereby permitting the improved morphologic localization of p53 phosphoprotein in paraffin embedded tissue. Of 33 primary head and neck carcinomas analyzed from AMeX-fixed, paraffin-embedded sections, 21 (64%) showed heterogeneous staining with PAb 1801. All 33 normal samples of head and neck tissues were negative. Similarly, 13 out of 20 lung carcinomas (65%) showed heterogeneous staining while none of normal lung tissues were positive. The data indicate a strong positive correlation between p53 detection by PAb 1801 and carcinomas of the head and neck and of lung. However, there was no obvious correlation between p53 staining and the number of involved nodes, the stage of disease or the degree of differentiation in these carcinomas.
Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Neoplasias Pulmonares/patología , Proteína p53 Supresora de Tumor/análisis , Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Inmunohistoquímica/métodos , Neoplasias Pulmonares/cirugía , Metástasis Linfática , Estadificación de NeoplasiasAsunto(s)
Enfermedades de la Aorta/complicaciones , Ecocardiografía/métodos , Insuficiencia Multiorgánica/etiología , Trombosis/complicaciones , Adulto , Aorta Torácica/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedad Crítica , Esófago , Femenino , Humanos , Insuficiencia Multiorgánica/diagnóstico por imagen , Trombosis/diagnóstico por imagenRESUMEN
In studies using bromodeoxyuridine (BrdUrd) and/or iododeoxyuridine (IdUrd) to label S phase cells in cancer patients, several unique observations were made regarding DNA replication sites and the organization of newly synthesized DNA in post-mitotic cells. While the majority of tumour specimens removed at the end of infusions demonstrated concentration of replication sites around the nuclear membrane, biopsies obtained in leukaemic patients 1 week later demonstrated several distinct patterns of labelling. For example, one, two or all lobes of granulocytes were labelled. Scavenger macrophages bearing labelled leukaemic cells in their cytoplasm were also seen. Sequential IdUrd/BrdUrd labelling of solid tumours showed various patterns of nuclear/nucleolar/membrane labelling, allowing more precise localization of early versus late replication sites.
Asunto(s)
Replicación del ADN , Neoplasias/patología , Anticuerpos Monoclonales , Neoplasias Encefálicas/patología , Bromodesoxiuridina/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Neoplasias Gastrointestinales/patología , Humanos , Idoxuridina/metabolismo , Técnicas para Inmunoenzimas , Leucemia/patología , Leucemia Mieloide/patología , Neoplasias/metabolismo , Fase SRESUMEN
We analyzed the expression of P-glycoprotein (Pgp) by immunohistochemistry using JSB-1 monoclonal antibody (MAb) on paraffin-embedded sections of the multi-drug resistant (MDR) (CHrC5 and CEM-VLB), and sensitive (AuxB1 and CEM) cell lines, and also in normal kidney, colon, adrenal and in kidney and colon carcinomas. After comparing the sensitivity of three different immunohistochemical techniques the peroxidase-antiperoxidase method was found to be the best. We then tested six different fixation methods. The MDR cell lines and human tissues demonstrated the strongest staining with B-5 fixative. Both MDR cell lines, but not the tissues fixed in 1% paraformaldehyde and Zamboni's fixative demonstrated weak staining. No immuno- reactivity could be detected in MDR cell lines and tissues fixed in 10% buffered or nonbuffered formalin or by the AMeX method of tissue processing. The present study clearly shows that the type of fixative is critical for the preservation of Pgp epitope recognized by JSB-1 MAb, and that B-5 fixative is expected to be equally applicable for the detection of Pgp in normal and neoplastic tissues.
Asunto(s)
Glándulas Suprarrenales/química , Anticuerpos Monoclonales , Colon/química , Neoplasias del Colon/química , Neoplasias Renales/química , Riñón/química , Glicoproteínas de Membrana/análisis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Glándulas Suprarrenales/citología , Animales , Células CHO , Colon/citología , Neoplasias del Colon/patología , Cricetinae , Fijadores/farmacología , Humanos , Inmunohistoquímica , Riñón/citología , Neoplasias Renales/patología , Adhesión en Parafina , Coloración y Etiquetado , Adhesión del Tejido , Células Tumorales CultivadasRESUMEN
A case is presented of anaemia which was caused by decubitus ulcer and fistula of the duodenum developed as a result of pressure exerted by aortofemoral vascular prosthesis.
Asunto(s)
Anemia/etiología , Prótesis Vascular/efectos adversos , Enfermedades Duodenales/etiología , Úlcera Duodenal/complicaciones , Fístula Intestinal/etiología , Humanos , Masculino , Persona de Mediana Edad , Presión/efectos adversosRESUMEN
To give operators of high-speed, highly-manoeuvrable vehicles the ability to keep pace with their increasingly dynamic environment, stereoscopic 3-D displays may soon replace conventional 2-D displays. Important to the development of stereoscopic 3-D displays is the interaction of perceived depth created by hues (chromostereopsis) and perceived depth created by presenting different images of a single object to the left and right eye of the observer (stereopsis). The purpose of this research is to evaluate the interaction of chromostereopsis and stereopsis on a stereoscopic CRT by determining the level of accuracy with which subjects can properly interpret the relative depth differences of adjacent symbols containing six levels of hue and seven levels of stereoscopic disparity. This research demonstrated that hue, disparity, and the interaction of hue and disparity significantly influenced one's perception of depth on a stereoscopic monitor. The results suggest that caution should be exercised by the stereoscopic 3-D display format designer when choosing hues to represent images located in close proximity on a stereoscopic display. Due to the chromostereoscopic effect on the perception of depth, hues on extreme ends of the colour spectrum should not be used in situations where less than 3.39 arc minutes of disparity difference is being portrayed on a stereoscopic display, unless the hues are consistently being used to alter the depth presented by stereoscopic disparity, or the chromostereoscopic depth resulting from certain hues is consistently nullified by altering disparity levels accordingly.
RESUMEN
In almost all studies using paraffin embedded tissue, c-myc protein has been found in the cytoplasm of cells. Since the protein is normally localized in the nucleus it is difficult to determine which histochemical observations are real and which are artefactual. The study designed here evaluated several different methods of fixation prior to paraffin embedding in an attempt to identify which would prevent the diffuse of the protein out of the nucleus. Using various fixation procedures (formalin, paraformaldehyde, B-5, Zamboni and AMeX) we found that fixation in cold acetone (-20 degrees C) overnight followed by 2x15 min fixation in acetone at +4 degrees c and at room temperature, cleared in methyl benzoate and xylene (AMeX procedure) gives reproducible nuclear staining when a variety of normal and tumor tissues are treated with an anti c-myc protein antibody. This method was then compared to frozen sections. While there was no cytoplasmic staining in same tissue specimens in both AMeX processed and frozen sections, the tissue architecture was much better preserved in AMeX processed samples. Our data strongly suggest that AMeX fixation, originally developed for T and B lymphocyte antigens, should be used for immunolocalization of c-myc oncoprotein in paraffin embedded tissues.
Asunto(s)
Proteínas Proto-Oncogénicas c-myc/metabolismo , Núcleo Celular/metabolismo , Técnicas Histológicas , Humanos , Inmunohistoquímica , Neoplasias/metabolismo , Neoplasias/ultraestructura , ParafinaRESUMEN
A cyclosporine-ketoconazole drug interaction was first described in 1981. It has been suggested that the two drugs should not be used concomitantly because of the danger of severe nephrotoxicity. Two reported cases indicate that cyclosporine and ketoconazole can be safely coadministered, provided that the dosage of cyclosporine is reduced appropriately. Two patients were initially given 8 mg/kg/day of cyclosporine at the time of heart transplantation, and the dosage was tapered to meet appropriate blood levels (250 to 350 ng/ml by whole blood high-performance liquid chromatography). During ketoconazole therapy (400 mg daily for 4 weeks), patient 1 received 80 to 100 mg/day of cyclosporine, which is equal to approximately 1 mg/kg/day, and patient 2 received between 40 and 80 mg/day of cyclosporine, which is equivalent to 0.4 to 0.8 mg/kg/day. Neither patient exhibited a creatinine value above 1.4 mg/dl while on combined therapy, and there were no problems with allograft rejection. Both patients had inappropriately high cyclosporine blood levels even with this marked reduction in dosage (patient 1, 520 to 1310 ng/ml and patient 2, 320 to 600 ng/ml). Thus it appears that cyclosporine and ketoconazole can be administered together safely, provided that there is an appropriate reduction in the dosage of cyclosporine; this results in the maintenance of adequate immunosuppression without development of nephrotoxicity.
Asunto(s)
Ciclosporinas/uso terapéutico , Trasplante de Corazón , Cetoconazol/uso terapéutico , Riñón/efectos de los fármacos , Quimioterapia Combinada , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Initial trials of irradiation and chemotherapy followed by operation for squamous carcinoma of the esophagus have produced encouraging results. Over the past three years, with palliative and curative intent, we have treated 27 unselected patients initially with two courses of chemotherapy (fluorouracil and either cisplatin, mitomycin, or cisplatin and vincristine sulfate) given 29 days apart and 3000 rad (30 Gy) of radiation. Ten patients have then undergone esophageal resection and two patients have undergone esophageal bypass. Results are compared with those of 70 unselected historical control patients treated since 1979. Survival at 30 months was significantly improved for multimodality-treated patients (21.4% +/- 10.1%, mean +/- SEM) when compared with historical control patients (4.8% +/- 2.7%). Twenty-four percent of multimodality-treated patients had complete remission of all tumor. These data indicate that overall therapy for carcinoma of the esophagus has been improved in our institutions.
Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/radioterapia , Humanos , Cuidados Preoperatorios , PronósticoRESUMEN
A retrospective analysis of 3650 endoscopies shows that frequency of inflammation and ulcer incidence both in the stomach and the duodenal bulb were similar in consecutive seasons of the year. The conclusion is drawn that there may be seasonal (circannual) factors which predispose aggression to mucosa both in the stomach and duodenum, which in turn leads to seasonal occurrence of inflammation as well as to ulcer incidence.
Asunto(s)
Enfermedades Duodenales/etiología , Estaciones del Año , Gastropatías/etiología , Enfermedades Duodenales/patología , Femenino , Gastroscopía , Humanos , Inflamación , Masculino , Estudios Retrospectivos , Gastropatías/patología , Úlcera Gástrica/etiología , Úlcera Gástrica/patologíaRESUMEN
This study examines and compares the prophylactic role of aprotinin and Dextran 40 in acute pancreatitis. Experimental acute pancreatitis was induced in 70 male Wistar rats using the closed-duodenal-loop technique. The rats were randomly divided into four groups; sham operation, untreated acute pancreatitis, and therapy with aprotinin or Dextran 40. Samples of blood and urine were collected at the beginning and at the end of the 24-hr period for measurement of amylase and creatinine which allowed calculation of the amylase-creatinine clearance ratio (ACCR). Mortality in the aprotinin group was the same as the untreated rats (20%). Dextran 40 therapy was associated with a lower mortality rate (6.7%). Light microscopic examination confirmed that the histologic changes of acute pancreatitis were less severe in both the aprotinin- and Dextran 40-treated rats. The ACCR was elevated after Dextran 40 therapy, which was due mainly to high urinary amylase levels. These results suggest that Dextran 40 may have a prophylactic role in acute experimental pancreatitis but again emphasizes the high false-positive rate of the ACCR determination.
Asunto(s)
Aprotinina/uso terapéutico , Dextranos/uso terapéutico , Pancreatitis/tratamiento farmacológico , Enfermedad Aguda , Amilasas/sangre , Animales , Creatinina/sangre , Masculino , Páncreas/patología , Pancreatitis/sangre , Pancreatitis/enzimología , Pancreatitis/patología , Ratas , Ratas EndogámicasRESUMEN
When examining the impact of automation in the cockpit, a careful distinction must be drawn between the role of a multi-crew civilian aircraft and a single-seat military aircraft. For the former, there are some concerns that automation can have a negative impact on the crew by reducing their proficiency. However, for a single-seat military aircraft on an attack mission, the role of automation is not only helpful to the pilot now but in the future may be necessary to achieve mission success. These distinctions must constantly be brought to mind in explaining the concepts of Fitts' principles. For a single-seat military aircraft, it is believed that these principles still apply, and that computer monitoring of system failures will further enhance their application. Three approaches to computer-augmented system monitoring are discussed.