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2.
Prostate Cancer Prostatic Dis ; 26(2): 317-322, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35314788

RESUMEN

BACKGROUND: This pilot prospective study investigated the effect of a periodic fasting mimicking diet (FMD) on metabolic health factors in patients with Prostate Cancer (PC). There is a well-documented association between PC and metabolic health. Impaired metabolic health is a significant risk factor for the development of PC, and a metabolic syndrome can be induced by hormonal therapies commonly required for its management. (ClinicalTrials.gov Identifier: NCT04292041). METHODS: We introduced a periodic 4-day FMD -low in calories, sugars, and proteins but high in unsaturated fats -to a cohort of PC patients and features of metabolic syndrome. 29/35 patients completed 3-monthly cycles of the 4-consecutive day packaged FMD. We compared the subjects' baseline weight, abdominal circumference (AC), blood pressure (BP) and selected laboratory results to the same measurements 3-months after completing the FMD cycles. RESULTS: Several important metabolic factors showed improvements post-intervention. On average patients' weights dropped by 3.79 kg (95% CI: -5.61, -1.97, p = 0.0002). AC was reduced on average by 4.57 cm, (95% CI: -2.27, -6.87, p = 0.0003). There was also a decrease in systolic and diastolic BP by 9.52 mmHg (95% CI: -16.16, -2.88, p = 0.0066) and 4.48 mmHg (95% CI: -8.85, -0.43, p = 0.0316) respectively. A sub-analysis indicates that FMD had more relevant effects in 'at-risk' patients than those with normal values of risk factors for metabolic syndrome. For example, subjects with baseline levels of systolic BP > 130 mmHg experienced a greater reduction in BP(-16.04 mmHg, p = 0.0001) than those with baseline systolic BP < 130 mmHg (-0.78 mmHg, p = 0.89). CONCLUSIONS: The FMD cycles were safely introduced to this small cohort of PC patients with little or no observed toxicity, and a high overall compliance of 83%. Analysis of the metabolic variables showed an overall decrease in weight, AC, and BP. Larger clinical trials focused on metabolic risk factors, PC quality of life and progression free survival are needed to assess the effect of the FMD on prostate cancer patients.


Asunto(s)
Hipertensión , Síndrome Metabólico , Neoplasias de la Próstata , Humanos , Masculino , Presión Sanguínea , Dieta , Ayuno , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Síndrome Metabólico/epidemiología , Síndrome Metabólico/complicaciones , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/complicaciones , Calidad de Vida , Proyectos Piloto
3.
Sci Rep ; 11(1): 11160, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-34045648

RESUMEN

An optical fibre sensor based on radioluminescence, using the scintillation material terbium doped gadolinium oxysulphide (Gd2O2S:Tb) is evaluated, using a 3D printed anthropomorphic phantom for applications in low dose-rate (LDR) prostate brachytherapy. The scintillation material is embedded in a 700 µm diameter cavity within a 1 mm plastic optical fibre that is fixed within a brachytherapy needle. The high spatial resolution dosimeter is used to measure the dose contribution from Iodine-125 (I-125) seeds. Initially, the effects of sterilisation on the sensors (1) repeatability, (2) response as a function of angle, and (3) response as a function of distance, are evaluated in a custom polymethyl methacrylate phantom. Results obtained in this study demonstrate that the output response of the sensor, pre- and post-sterilisation are within the acceptable measurement uncertainty ranging from a maximum standard deviation of 4.7% pre and 5.5% post respectively, indicating that the low temperature sterilisation process does not damage the sensor or reduce performance. Subsequently, an LDR brachytherapy plan reconstructed using the VariSeed treatment planning system, in an anthropomorphic 3D printed training phantom, was used to assess the suitability of the sensor for applications in LDR brachytherapy. This phantom was printed based on patient anatomy, with the volume and dimensions of the prostate designed to represent that of the patient. I-125 brachytherapy seeds, with an average activity of 0.410 mCi, were implanted into the prostate phantom under trans-rectal ultrasound guidance; following the same techniques as employed in clinical practice by an experienced radiation oncologist. This work has demonstrated that this sensor is capable of accurately identifying when radioactive I-125 sources are introduced into the prostate via a brachytherapy needle.


Asunto(s)
Braquiterapia/métodos , Fibras Ópticas , Neoplasias de la Próstata/radioterapia , Humanos , Radioisótopos de Yodo/uso terapéutico , Masculino , Impresión Tridimensional , Dosificación Radioterapéutica , Ultrasonografía Intervencional
4.
Biomed Opt Express ; 11(7): 4027-4036, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33014583

RESUMEN

An optical fiber sensor for monitoring low dose radiation is presented. The sensor, based on radiation sensitive scintillation material, terbium doped gadolinium oxysulphide (Gd2O2S:Tb), is embedded in a cavity of 700µm diameter within a 1mm plastic optical fiber. The sensor is compared with the treatment planning system for repeatability, angular dependency, distance and accumulated radiation activity. The sensor demonstrates a high sensitivity of 152 photon counts/Gy with a temporal resolution of 0.1 seconds, with the largest repeatability error of 4.1%, to 0.361mCi of Iodine-125 the radioactive source most commonly used in LDR brachytherapy for treating prostate cancer.

5.
Cancer Nanotechnol ; 7(1): 7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27818715

RESUMEN

Review is made of dosimetric studies of current optical fibre technology in radiotherapy for therapeutic applications, focusing particularly on in vivo dosimetry for prostate radiotherapy. We present the various sensor designs along with the main advantages and disadvantages associated with this technology. Optical fibres are ideally placed for applications in radiotherapy dosimetry; due to their small size they are lightweight and immune to electromagnetic interferences. The small dimensions of optical fibres allows it to be easily guided within existing brachytherapy equipment; for example, within the seed implantation needle for direct tumour dose analysis, in the urinary catheter to monitor urethral dose, or within the biopsy needle holder of the transrectal ultrasound probe to monitor rectal wall dose. The article presents the range of optical fibre dosimeter designs along with the main dosimetric properties required for a modern in vivo dosimetry system to be utilised in a clinical environment.

8.
Br J Cancer ; 109(8): 2131-41, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24052043

RESUMEN

BACKGROUND: Taxanes are routinely used for the treatment of prostate cancer, however the majority of patients eventually develop resistance. We investigated the potential efficacy of EL102, a novel toluidine sulphonamide, in pre-clinical models of prostate cancer. METHODS: The effect of EL102 and/or docetaxel on PC-3, DU145, 22Rv1 and CWR22 prostate cancer cells was assessed using cell viability, cell cycle analysis and PARP cleavage assays. Tubulin polymerisation and immunofluorescence assays were used to assess tubulin dynamics. CWR22 xenograft murine model was used to assess effects on tumour proliferation. Multidrug-resistant lung cancer DLKPA was used to assess EL102 in a MDR1-mediated drug resistance background. RESULTS: EL102 has in vitro activity against prostate cancer, characterised by accumulation in G2/M, induction of apoptosis, inhibition of Hif1α, and inhibition of tubulin polymerisation and decreased microtubule stability. In vivo, a combination of EL102 and docetaxel exhibits superior tumour inhibition. The DLKP cell line and multidrug-resistant DLKPA variant (which exhibits 205 to 691-fold greater resistance to docetaxel, paclitaxel, vincristine and doxorubicin) are equally sensitive to EL102. CONCLUSION: EL102 shows potential as both a single agent and within combination regimens for the treatment of prostate cancer, particularly in the chemoresistance setting.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Sulfonamidas/farmacología , Toluidinas/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Docetaxel , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Humanos , Masculino , Ratones , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Distribución Aleatoria , Sulfonamidas/administración & dosificación , Taxoides/administración & dosificación , Toluidinas/administración & dosificación , Tubulina (Proteína)/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Free Radic Biol Med ; 27(5-6): 529-35, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10490272

RESUMEN

Reactive oxygen species play critical roles in a number of physiologic and pathologic processes. Nitroxides are stable free radical compounds that possess superoxide dismutase (SOD) mimetic activity and have been shown to protect against the toxicity of reactive oxygen species in vitro and in vivo. Tempol, a cell-permeable hydrophilic nitroxide, protects against oxidative stress and also is an in vitro and in vivo radioprotector. In the course of evaluating the pharmacology and toxicity of the nitroxides, Tempol and another nitroxide, 3-carbamoyl-PROXYL (3-CP), were administered intravenously in various concentrations to miniature swine. Tempol caused dose-related hypotension accompanied by reflex tachycardia and increased skin temperature. Invasive hemodynamic monitoring with Swan Ganz catheterization (SGC) confirmed the potent vasodilative effect of Tempol. However, 3-CP had no effect on porcine blood pressure. The hemodynamic effects of Tempol and 3-CP are discussed in the context of differential catalytic rate constants for superoxide disumation that may impact systemic nitric oxide (NO) levels and lead to vasodilation. These findings are consistent with a role for the superoxide ion in the modulation of blood pressure and have potential implications for the systemic use of nitroxides.


Asunto(s)
Óxidos N-Cíclicos/farmacología , Hemodinámica/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Animales , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Hipotensión/inducido químicamente , Óxido Nítrico/farmacología , Pirrolidinas/farmacología , Protectores contra Radiación/farmacología , Especies Reactivas de Oxígeno/metabolismo , Temperatura Cutánea/efectos de los fármacos , Marcadores de Spin , Porcinos , Porcinos Enanos , Taquicardia/inducido químicamente , Resistencia Vascular/efectos de los fármacos , Vasodilatadores/farmacología
10.
Free Radic Biol Med ; 22(7): 1211-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9098095

RESUMEN

Tempol, a stable nitroxide free radical compound, is an in vitro and in vivo radioprotector. Previous studies have shown that Tempol protects C3H mice against whole-body radiation-induced bone marrow failure. In this study, the radioprotection of tumor tissue was evaluated. RIF-1 tumor cells were implanted in female C3H mice 10 d prior to radiation. Groups of mice were injected intraperitoneally with Tempol (275 mg/kg) or PBS followed 10 min later by a single dose of radiation to the tumor bed. Tumor growth curves generated after 10 and 33.3 Gy doses of radiation showed no difference in growth between the Tempol- and PBS-treated animals. A full radiation dose-response experiment revealed a tumor control dose in 50% of the animals in 30 d (TCD(50/30)) value of 36.7 Gy for Tempol-treated mice and 41.8 Gy for saline-treated mice suggesting no protection of the RIF-1 tumor by Tempol. Tumor pharmacokinetics were done to determine why Tempol differentially protected bone marrow and not tumor cells. Differential reduction of Tempol in the RIF-1 tumor and bone marrow was evaluated with EPR spectroscopy 10, 20, and 30 min after injection. Bioreduction of Tempol to its corresponding hydroxylamine (which is not a radioprotector) occurred to a greater extent in RIF-1 tumor cells compared to bone marrow. We conclude that the differences in radioprotection may result from enhanced intratumor bioreduction of Tempol to its nonradioprotective hydroxylamine analogue. The nitroxides as a class of compounds may provide a means to exploit the redox differences between normal tissues and tumors.


Asunto(s)
Óxidos N-Cíclicos/farmacología , Neoplasias Experimentales/patología , Tolerancia a Radiación/efectos de los fármacos , Protectores contra Radiación/farmacología , Animales , Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de la radiación , División Celular/efectos de los fármacos , Óxidos N-Cíclicos/metabolismo , Óxidos N-Cíclicos/farmacocinética , Espectroscopía de Resonancia por Spin del Electrón , Femenino , Ratones , Ratones Endogámicos C3H , Trasplante de Neoplasias , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/radioterapia , Protectores contra Radiación/farmacocinética , Marcadores de Spin
11.
J Cell Biochem Suppl ; 24: 152-9, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8806097

RESUMEN

The enormous problem that is lung cancer still defies satisfactory therapeutic strategy. This article summarizes some of the more important laboratory efforts directed at understanding the biology of this complex disease. The radiation sensitivities of established lung cancer cell lines are outlined. The effect of radiation dose rate and chemotherapy is explored. The emerging biology of oncogenetic alterations is explored as it relates to radiation sensitivity in general, and lung cancer in particular. Finally, novel therapeutic approaches including photodynamic therapy are introduced.


Asunto(s)
Neoplasias Pulmonares/radioterapia , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/patología , Carcinoma de Células Pequeñas/radioterapia , Relación Dosis-Respuesta en la Radiación , Resistencia a Antineoplásicos , Células HeLa/efectos de los fármacos , Células HeLa/efectos de la radiación , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Oncogenes/efectos de la radiación , Fotoquimioterapia , Tolerancia a Radiación , Células Tumorales Cultivadas/efectos de la radiación , Ensayo de Tumor de Célula Madre
12.
Int J Radiat Oncol Biol Phys ; 30(3): 583-90, 1994 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-7928489

RESUMEN

PURPOSE: We report the outcome of a Phase II study of a cohort of patients with high-grade glioma treated with accelerated hyperfractionated radiation and the radiation sensitizer, iododeoxyuridine (IdUrd). METHODS AND MATERIALS: Between January 1988 and December 1990, 39 consecutive patients with high-grade glioma were enrolled and treated on a Phase II protocol including hyperfractionated radiation and IdUrd. Thirty-two patients were male and seven were female. Age range was 19 to 71 years with a median age of 38 years. IdUrd (1000 mg/m2 per day) was administered in two separate 14-day courses, the first during the initial radiation field and the second during the final cone-down field. All patients were treated consistently with partial brain technique and received 1.5 Gy/fraction twice daily to a mean total dose of 71.25 Gy (range 66-72 Gy excluding one patient who did not complete treatment). The initial field was treated to 45 Gy followed by a cone-down field covering the tumor volume plus a 1-cm margin to the final dose. Patients were assessed for acute and long-term morbidity and followed for outcome. Two patients had biopsies during the course of treatment. Flow cytometry and high performance liquid chromatography was used to evaluate the labeling index and the percent replacement of IdUrd in the biopsy specimen. RESULTS: Thirty-eight of 39 patients completed therapy. One patient died on treatment at 48 Gy and is included in the survival analysis. No patient was lost to follow-up. Twenty-one patients had Grade 3 (anaplastic astrocytoma) tumors and 18 patients had Grade 4 (glioblastoma multiforme). Median survival for the entire cohort was 23 months. For the glioblastoma multiforme patients, median survival was 15 months. The median survival of the anaplastic astrocytoma patients has not yet been reached. In the patients assessed, the range of IdUrd tumor cell incorporation was only 0-2.4%. CONCLUSION: Accelerated hyperfractionated radiation therapy with IdUrd was administered with acceptable acute toxicity. The major acute side effects of mucositis and thrombocytopenia were related to IdUrd infusion and were dose-dependent. There were no unacceptable acute toxicities referable to the radiation as delivered. With a median potential follow-up of 51 months, the actuarial median survival of the glioblastoma multiforme patients is comparable with the best previously published reports. The outcome of patients with anaplastic astrocytoma compares very favorably with even the most aggressive multi-modality approaches in the recent literature with a minimum of acute morbidity.


Asunto(s)
Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Idoxuridina/administración & dosificación , Adulto , Anciano , Astrocitoma/cirugía , Neoplasias Encefálicas/cirugía , Terapia Combinada , Femenino , Glioblastoma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Fármacos Sensibilizantes a Radiaciones , Análisis de Supervivencia
13.
Clin Plast Surg ; 20(3): 435-53, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8324983

RESUMEN

Radiation therapy exerts both acute and chronic effects on normal tissue included within treatment fields. The physics of radiation therapy and treatment techniques to minimize deleterious effects of radiation are presented. Management of radiation-damaged skin is discussed. Radiation effect on tissue, wound healing, and tumorigenesis also are reviewed.


Asunto(s)
Radioterapia/efectos adversos , Cicatrización de Heridas/efectos de la radiación , Animales , Humanos , Neoplasias Inducidas por Radiación , Radiobiología , Radioterapia/métodos , Piel/efectos de la radiación , Neoplasias Cutáneas/etiología
14.
Am J Hematol ; 38(1): 54-60, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1897515

RESUMEN

This report describes a patient with lymphocyte depleted Hodgkin's disease who presented with bone marrow aplasia. The aplastic marrow reverted to normal after initiation of MOPP chemotherapy; however, 4 months after completion of therapy, bone marrow aplasia recurred in the absence of recurrent Hodgkin's disease. The patient remains free of Hodgkin's disease 34 months after completion of chemotherapy. Bone marrow abnormalities in Hodgkin's disease are reviewed and the current understanding of the pathological mechanisms leading to aplastic anemia is discussed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Médula Ósea/patología , Enfermedad de Hodgkin/patología , Linfocitos/patología , Adulto , Biopsia , Médula Ósea/diagnóstico por imagen , Femenino , Enfermedad de Hodgkin/tratamiento farmacológico , Humanos , Mecloretamina/uso terapéutico , Estadificación de Neoplasias , Prednisona/uso terapéutico , Procarbazina/uso terapéutico , Radiografía , Factores de Tiempo , Vincristina/uso terapéutico
15.
Cancer ; 61(8): 1587-93, 1988 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-2450633

RESUMEN

Circulating cerebriform lymphoid cells (Sezary cells) are considered to be highly predictive of cutaneous T-cell Lymphoma (CTCL). A leukemic peripheral blood (leukocyte count 24.5 x 10(9)/l) composed predominantly of cerebriform cells was found in a 75-year-old man presenting with weight loss and generalized lymphadenopathy but without skin lesions. Cell suspensions studies and immunohistochemistry of peripheral blood revealed that the cerebriform cells were B-cells (IgM+ Kappa+, HLA DR+, Leu 1+, CALLA-, B1+, and OKT 10+). A variety of T-cell markers (other than Leu1) was negative. Computer-assisted morphometry confirmed a nuclear profile typical of CTCL (mean nuclear contour index, 7.47). A lymph node that underwent subsequent biopsy revealed a follicular malignant lymphoma of small to intermediate cells with similar morphologic and immunologic characteristics to the circulating cerebriform cells. The findings of a leukemic presentation of a cerebriform B-cell lymphoma extends the recent observation of nodal B-cell lymphomas composed of cerebriform cells and indicates that circulating cerebriform cells should not be considered to be exclusively of T-cell origin.


Asunto(s)
Linfocitos B/patología , Linfoma Folicular/patología , Anciano , Antígenos de Neoplasias/análisis , Antígenos de Superficie/análisis , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfocitos B/clasificación , Bleomicina/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Humanos , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/radioterapia , Masculino , Fenotipo , Prednisona/administración & dosificación , Linfocitos T/patología , Vincristina/administración & dosificación
16.
J Relig Health ; 26(4): 309-22, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24302070

RESUMEN

This article examines the use of the initiation ritual of primitive people, described in the works of Mircea Eliade, as a model for counseling cancer patients, giving both meaning and structure to the interactions between patient and counselor. Within this model the patient's encounter with death, whether feared or actualized, can be used as impetus toward personal growth, whatever the stage of the person's disease process. Case examples are given to illustrate how the model can be used in practice. Comparison is also made between stages and components of the initiation ritual and other techniques used to alter a person's consciousness.

17.
J Nutr ; 107(3): 426-35, 1977 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-557535

RESUMEN

Metabolic responses associated with prolonged fasting and subsequent refeeding of pigs were investigated. Fasting for 14 or 28 days produced significant increases in serum levels of alanine, aspartic and glutamic acid in the three branched-chain amino acids. Glycine, serine and lysine levels were elevated after 28 days of fasting while the levels of histidine, methionine, threonine and phenylalanine were reduced. Fasting markedly stimulated hepatic and renal gluconeogenesis and the activity of the urea cycle enzymes. Fatty acid synthesis and glucose oxidation were virtually abolished in hepatic and adipose tissue in pigs subjected to a 14- or 28-day fast. After the first day of refeeding, the levels of amino acids returned to the control values. The activity of the hepatic urea cycle enzymes, fructose-1,6-diphosphatase and phosphoenolpyruvate carboxykinase remained elevated after the first day of refeeding but returned to the control levels thereafter. The activity of hepatic glucose-6-phosphate dehydrogenase, malic dehydrogenase and acetyl CoA carboxylase were slightly enhanced in pigs refed for 4 and 8 days. The activity of these enzymes in adipose tissue was enhanced 8 days after refeeding. Hepatic synthesis of fatty acids from glucose was slightly stimulated in refed pigs on days 4 and 8 but returned to control values on day 16. Refeeding did not enhance glucose incorporation into fatty acids in adipose tissue above the values observed in fed controls.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Ayuno , Porcinos/metabolismo , Aminoácidos/metabolismo , Animales , Peso Corporal , Gluconeogénesis , Humanos , Metabolismo de los Lípidos , Hígado/metabolismo , Masculino , Urea/metabolismo
18.
Mil Med ; 141(11): 764-70, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-824570
19.
Am J Clin Nutr ; 29(6): 604-13, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1064332

RESUMEN

The nutrient intake and urinary excretion characteristics of eight young university women were studied over a 4-day period at low altitude (140 m) and subsequently over a 7-day sojourn on Pikes Peak (4,300 m). High-altitude exposure was associated with a transient decrease in the consumption of protein, carbohydrate, fat, sodium, calcium, phosphorus, vitamin A, riboflavin, thiamin, and niacin and a more sustained decrease in the consumption of potassium and ascorbic acid. In most instances minimal values were observed during the first 3 days of exposure. The carbohydrate fraction of energy intake was increased at the expense of fat during this time period. Individual hypophagic responses appeared to be related to severity of acute mountain sickness. Altitude had no effect on water consumption but did lead to an average body weight loss of 1 kg. Urinary measurements revealed a marked oliguria during the entire sojourn. These measurements also showed the first 3 days to be associated with a net loss of body nitrogen and sodium. During this time period body potassium and phosphorus were conserved, and probably increased. The urea fraction of body potassium and phosphorus were conserved, and probably increased. The urea fraction of total urinary nitrogen was not affected by altitude exposure, nor was the daily excretion of uric acid and creatinine. Ammonia excretion, however, was reduced to 50% of the low-altitude value and remained at this level throughout the sojourn. With a few exceptions, the qualitative characteristics of altitude hypophagia in women were similar to those reported for men. Quantitatively, however, the responses were much more transient in women.


Asunto(s)
Altitud , Dieta , Nitrógeno , Adolescente , Adulto , Mal de Altura/complicaciones , Mal de Altura/metabolismo , Peso Corporal , Carbohidratos de la Dieta , Grasas de la Dieta , Proteínas en la Dieta , Ingestión de Líquidos , Metabolismo Energético , Trastornos de Alimentación y de la Ingestión de Alimentos/etiología , Femenino , Humanos , Minerales , Nitrógeno/metabolismo , Oliguria/etiología , Factores Sexuales , Vitaminas , Agua/metabolismo
20.
Ann Surg ; 181(2): 232-8, 1975 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1089394

RESUMEN

Three hundred dye-dilution curves taken during our first year of clinical experience with the Waters CO-4 cardiac output computer were analyzed to estimate the errors involved in its use. Provided that calibration is accurate and 5.0 mg of dye are injected for each curve, then the percentage standard deviation of measurement using this computer is about 8.7%. Included in this are the errors inherent in the computer, errors due to baseline drift, errors in the injection of dye and acutal variation of cardiac output over a series of successive determinations. The size of this error is comparable to that involved in manual calculation. The mean value of five successive curves will be within 10% of the real value in 99 cases out of 100. Advances in methodology and equipment are discussed which make calibration simpler and more accurate, and which should also improve the quality of computer determination. A list of suggestions is given to minimize the errors involved in the clinical use of this equipment.


Asunto(s)
Gasto Cardíaco/instrumentación , Computadores Analógicos/normas , Diagnóstico por Computador/normas , Técnica de Dilución de Colorante/instrumentación , Gasto Cardíaco/normas , Diagnóstico por Computador/instrumentación , Errores Diagnósticos , Técnica de Dilución de Colorante/normas , Humanos , Oscilometría , Control de Calidad , Estadística como Asunto
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