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1.
Artículo en Inglés | MEDLINE | ID: mdl-11495381

RESUMEN

OBJECTIVES: To describe health technology assessment (HTA) and policies concerning three screening procedures in Sweden. METHODS: The main source of information was reports from the Swedish Council for Technology Assessment in Health Care (SBU) and other governmental reports, supplemented by the professional literature. RESULTS: Prevention is emphasized in the healthcare services of Sweden. Specifically, screening is encouraged and supported when it is deemed beneficial. Sweden has a strong orientation toward evidence-based health care and HTA. Since its inauguration in 1987, SBU has fostered the use of HTA in making policy and clinical decisions in Sweden. Government policy in Sweden is to encourage services that are beneficial and cost-effective and discourages services that are not. Screening is no exception to this general rule. The three cases examined in this paper-mammography screening, PSA screening, and routine ultrasound screening in pregnancy-have all been formally assessed in Sweden. Assessments have been an integral part of policy making concerning these and other preventive measures. Mammography screening has been widely implemented. However, as in other countries, screening is often carried out in an opportunistic fashion, so that PSA screening, in particular, is carried out more in Sweden than can be justified by the evidence. CONCLUSIONS: Mammography screening is promoted and is completely available to the target group. PSA screening is discouraged, but not with complete success. Ultrasound in pregnancy is widely used, not because of good evidence of impact on mortality and morbidity among newborns, but because it increases the detection rate of congenitally malformed fetuses and because of evidence of positive effects on the management and planning of deliveries, as well as because of psychological and ethical implications of the technology. HTA is an important part of health policy making in Sweden.


Asunto(s)
Política de Salud , Mamografía/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Antígeno Prostático Específico/sangre , Evaluación de la Tecnología Biomédica , Ultrasonografía Prenatal/estadística & datos numéricos , Adulto , Anciano , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/prevención & control , Suecia
2.
Eur J Surg Oncol ; 25(2): 179-85, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10218462

RESUMEN

AIMS: To determine the toxicity and efficacy of isolated hepatic perfusion with tumour necrosis factor alpha (TNF-alpha) and melphalan (Alkeran) under mild hyperthermic conditions. METHODS: A phase I trial was performed. Eleven patients with unresectable metastatic malignancies in the liver were pre-treated with 3 x 10(6) U leukocyte IFN daily 2 days before the perfusion. The liver was isolated and inflow catheters inserted in the hepatic artery and the portal vein. The hepatic veins were drained via a catheter in the retrohepatic caval vein. The venous blood flow from the lower extremities and the splanchnic circulation was bypassed to the axillar vein. The liver circuit was perfused with oxygenated blood and 30-200 microg TNF-alpha was added. At 39 degrees C in the liver circuit 0.5 mg/kg melphalan was added and the perfusion was continued for 1 h. RESULTS: Six patients underwent re-operation due to post-operative bleeding. Two patients died of coagulopathy or multiple organ failure within the first post-operative month. Three of six patients with liver metastases from malignant melanoma or leiomyosarcoma showed a partial response while no patients with liver metastases from colorectal cancer showed any response. The mean survival time was 20 months, which is within the same range as seen in previous isolated hepatic perfusion (IHP) studies. CONCLUSIONS: IHP with this drug regimen is a method with a considerable toxicity, though it is hard to distinguish between toxicity from TNF-alpha and that from the perfusion procedure itself. The method was not effective in patients with colorectal liver metastasis, but the results in melanoma and leiomyosarcoma patients warrant further studies.


Asunto(s)
Antineoplásicos/uso terapéutico , Quimioterapia del Cáncer por Perfusión Regional , Oxigenación por Membrana Extracorpórea , Arteria Hepática , Hipertermia Inducida , Neoplasias Hepáticas/terapia , Melfalán/uso terapéutico , Factor de Necrosis Tumoral alfa/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Colorrectales/patología , Femenino , Humanos , Leiomiosarcoma/secundario , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Masculino , Melanoma/secundario , Persona de Mediana Edad , Radiografía
3.
Eur J Surg ; 164(8): 569-74, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9720932

RESUMEN

OBJECTIVE: To evaluate treatment of patients with primary liver cancer. DESIGN: Prospective protocol including subsets of randomised studies. SETTING: University hospital, Sweden. SUBJECTS: 123 patients with primary liver cancer. INTERVENTIONS: 64 patients underwent hepatic resection, 25 were included in a trial of adjuvant chemotherapy. 24 further patients whose tumours were not resectable were included in a trial of intra-arterial infusion of doxorubicin. MAIN OUTCOME MEASURES: Survival and postoperative morbidity. RESULTS: The median survival time for patients who had had resections was 11 months (range 0-111). Twelve per cent survived more than 5 years. No prognostic factor had any significant effect on outcome. The postoperative mortality was 11% (7/64). The patients allocated to adjuvant chemotherapy survived a median of 10 months (range 1-47) and the controls 29 months (range 8-111) (p=0.04). Patients with unresectable liver cancer treated with intra-arterial doxorubicin lived no longer than untreated controls (median 8 months (range 1-56) compared with 7 months (range 1-28)). CONCLUSIONS: Treatment of patients with primary liver cancer is still an unsolved problem. Adjuvant chemotherapy with doxorubicin had no beneficial effect on survival.


Asunto(s)
Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Adulto , Anciano , Quimioterapia Adyuvante , Doxorrubicina/administración & dosificación , Hepatectomía , Humanos , Infusiones Intraarteriales , Neoplasias Hepáticas/mortalidad , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Suecia/epidemiología , Resultado del Tratamiento
4.
Recent Results Cancer Res ; 147: 13-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9670264

RESUMEN

Isolated hyperthermic liver perfusion is a transitional therapy, i.e. a therapy between evidence based, standard therapy and experimental therapy. It appears to provide distinct benefits in a number of situations but the scientific evidence is still incomplete. In our view the present indications for use of isolated hyperthermic perfusion of the liver are: to gain more knowledge; nonresectable liver metastases without proven extrahepatic growth from: uveal melanoma, colorectal carcinoma, and ovarian cancer; symptoms related to hepatic metastases from endocrine tumors. A multicenter study aimed at gaining more knowledge is recommended.


Asunto(s)
Quimioterapia del Cáncer por Perfusión Regional/métodos , Cirugía General , Hipertermia Inducida , Emociones , Medicina Basada en la Evidencia , Transición de la Salud , Experimentación Humana , Humanos
5.
Acta Physiol Scand ; 162(4): 495-500, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9597117

RESUMEN

Changes in energy phosphates of rabbit kidneys subjected to ischaemia-reperfusion have been measured in vivo with volume selective 31P NMR spectroscopy. The effects of pretreatment with a new lipid peroxidation inhibitor (indeno-indol derivate--code name H290/51) on the bioenergetic changes were analysed. The left kidney was moved to a subcutaneous pocket to facilitate exact positioning over the surface coil. A 1H NMR image was acquired and a 3.5-mL cube selected for 31P NMR spectra. 31P NMR spectra were recorded before occlusion of the left renal artery, during 1 h of ischaemia and 2 hours of reperfusion. Ischaemia induced drastic changes in the levels of inorganic phosphates and ATP as well as intracellular acidosis. A normalization was observed during reperfusion. Two hours after reperfusion significantly higher values for beta-ATP/Pi and intracellular pH were recorded in the animals pretreated with H290/51. The present technique allows quantitative analyses of changes in kidney bioenergetics in vivo during different experimental conditions. The importance of ischaemia-reperfusion induced lipid peroxidation for mitochondrial function is emphasized.


Asunto(s)
Antioxidantes/farmacología , Metabolismo Energético , Indoles/farmacología , Riñón/metabolismo , Daño por Reperfusión/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Riñón/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Isótopos de Fósforo , Conejos , Daño por Reperfusión/tratamiento farmacológico
6.
Acta Physiol Scand ; 161(3): 403-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9401594

RESUMEN

The effects of 60 min of ischaemia with or without reoxygenation in vivo or in vitro on lipid peroxidation in cortical and medullary tissue from rabbit kidneys were measured as production of thiobarbituric acid-reactive substances (TBARS). Lipid peroxidation was more pronounced in medullary tissue compared with cortical tissue. The highest TBARS production was found in medullary slices subjected to reoxygenation in vitro immediately after 1 h of ischaemia. Reperfusion in vivo before reoxygenation in vitro attenuated the TBARS formation during subsequent in vitro incubation. Pretreatment of the rabbits with an indeno-indole compound (code name H 290/51) reduced the TBARS formation after 60 min of ischaemia and reoxygenation in vitro towards control values.


Asunto(s)
Antioxidantes/farmacología , Corteza Cerebral/metabolismo , Indoles/farmacología , Peroxidación de Lípido/efectos de los fármacos , Bulbo Raquídeo/metabolismo , Circulación Renal/efectos de los fármacos , Daño por Reperfusión/metabolismo , Animales , Corteza Cerebral/efectos de los fármacos , Femenino , Isquemia/metabolismo , Bulbo Raquídeo/efectos de los fármacos , Conejos , Sustancias Reactivas al Ácido Tiobarbitúrico
7.
Am J Physiol ; 272(1 Pt 2): H83-90, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9038925

RESUMEN

The effect of intravenously administered ascorbate on the ischemic and reperfused rat skeletal muscle was investigated. Purine nucleotides and phospholipids in skeletal muscle from rats subjected to 4 h of ischemia followed by 1-h reperfusion were analyzed by high-performance liquid chromatography. In addition, ATP, phosphocreatine (PCr), Pi, and phosphomonoesters (PME) were analyzed by 31P-nuclear magnetic resonance at 202.4 MHz, and individual PME such as glucose-6-phosphate and IMP were quantified. PCr and ATP were exhausted after 4 h of ischemia and recovered poorly upon reperfusion in the soleus and tibialis muscle of untreated rats. Postischemic reperfusion resulted in significant loss of cardiolipin. Treatment with 55 mM ascorbate resulted in total restoration of PCr during reperfusion, and ATP recovered to 42% of control in the soleus. Recovery was improved in the tibialis as well, and the cardiolipin decrease was limited. A lower ascorbate concentration (5 mM) did not enhance postischemic recovery. Our findings show that a high dose of ascorbate improves the energetic state of rat skeletal muscle during postischemic reperfusion, probably due to its antioxidant function.


Asunto(s)
Ácido Ascórbico/farmacología , Isquemia/metabolismo , Músculo Esquelético/irrigación sanguínea , Fosfolípidos/metabolismo , Nucleótidos de Purina/metabolismo , Reperfusión , Animales , Cardiolipinas/metabolismo , Bovinos , Cromatografía Líquida de Alta Presión , Metabolismo Energético , Femenino , Espectroscopía de Resonancia Magnética , Músculo Esquelético/efectos de los fármacos , Fosfatos/metabolismo , Fosfatidiletanolaminas/metabolismo , Ratas , Ratas Sprague-Dawley
8.
World J Surg ; 20(7): 892-9; discussion 899, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8678968

RESUMEN

Sixty-four consecutive patients with disseminated midgut carcinoids were treated during an 8-year period according to a single clinical protocol aimed at aggressive tumor reduction by surgery alone or with subsequent hepatic artery embolization. All patients had markedly elevated urinary 5-hydroxyindoleacetic acid (5-HIAA) levels (581 +/- 79 micromol/24 h) and hormonal symptoms. Fourteen patients (22%) reached anatomic and biochemical cure by surgery alone. At follow-up, the mean 5-HIAA levels were still normal after 69.0 +/- 6. 2 months; two patients had died from unrelated causes. With the introduction of somatostatin receptor scintigraphy, subclinical disease was diagnosed in 7 of these 14 patients. Forty patients with bilobar hepatic disease underwent embolization in combination with octreotide. In this group, 5-HIAA levels were still reduced by 55% after 71 +/- 11 months of follow-up, and the 5-year survival was 56%, estimated from the total death hazard function. After embolization, two subgroups could be identified with marked differences in their long-term response to treatment. Ten patients were not embolized owing to complicating diseases. The 5-year survival for the entire series was 58%. A significantly increased risk of cardiovascular deaths was seen, which underlines the importance of total survival analysis in a disease with multiple hormonal effects. It is concluded that an active surgical approach must be recommended to patients with the midgut carcinoid syndrome. In patients with bilobar hepatic disease, embolization combined with octreotide treatment markedly reduced the 5-HIAA excretion and suggested a prolonged 5-year survival.


Asunto(s)
Tumor Carcinoide/cirugía , Neoplasias Intestinales/cirugía , Adulto , Anciano , Antineoplásicos Hormonales/uso terapéutico , Tumor Carcinoide/patología , Tumor Carcinoide/secundario , Tumor Carcinoide/orina , Causas de Muerte , Protocolos Clínicos , Terapia Combinada , Muerte Súbita Cardíaca , Embolización Terapéutica , Femenino , Estudios de Seguimiento , Arteria Hepática , Humanos , Ácido Hidroxiindolacético/orina , Radioisótopos de Indio , Neoplasias Intestinales/patología , Neoplasias Intestinales/orina , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Masculino , Persona de Mediana Edad , Octreótido/análogos & derivados , Octreótido/uso terapéutico , Ácido Pentético/análogos & derivados , Radiofármacos , Receptores de Somatostatina/análisis , Inducción de Remisión , Factores de Riesgo , Análisis de Supervivencia , Tasa de Supervivencia
9.
Acta Physiol Scand ; 157(2): 289-97, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8800371

RESUMEN

Lipid peroxidation of mitochondrial and cell membrane structures is the final step in the oxygen radical-induced damage observed at reperfusion of kidneys after ischaemia. We compared the ability of an indeno-indol compound (code name H290/51) with that of alpha-tocopherol to inhibit lipid peroxidation in reoxygenated isolated rat renal tissue in vitro measured as production of TBARS (thiobarbituric acid reactive substances). H290/51 was 100 times more efficient than alpha-tocopherol. Treatment of rats in vivo with H290/51 in a dosage giving a plasma concentration of 500 nmol L-1 inhibited TBARS production measured in vitro by 80%. Treatment of rabbits with H290/51 almost completely inhibited radical production at reperfusion after 60 min of ischaemia measured with spin trap technique using OXANOH (2-ethyl-3-hydroxy-2,4,4-trimethyloxazolidine) as a spin trap. Furthermore, such pretreatment significantly improved kidney function and survival of rabbits subjected to 60 min of ischaemia to the left kidney and contralateral nephrectomy. These studies stress the importance of inhibiting lipid peroxidation to prevent the ischaemia-reperfusion damage and furthermore suggest a role for treatment with antioxidants like H290/51 in clinical practice, e.g. at reconstructive renal surgery and transplantation.


Asunto(s)
Antioxidantes/farmacología , Indoles/farmacología , Isquemia/fisiopatología , Riñón/fisiología , Peroxidación de Lípido/efectos de los fármacos , Daño por Reperfusión/fisiopatología , Animales , Antioxidantes/uso terapéutico , Diuréticos Osmóticos/farmacología , Femenino , Radicales Libres , Técnicas In Vitro , Indoles/sangre , Indoles/uso terapéutico , Isquemia/tratamiento farmacológico , Riñón/irrigación sanguínea , Riñón/efectos de los fármacos , Pruebas de Función Renal , Manitol/farmacología , Nefrectomía , Conejos , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
10.
World J Surg ; 20(2): 196-202, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8661817

RESUMEN

Liver metastases imply a major problem in patients with carcinoid tumors. Patients with localized disease should always undergo resection for cure. Patients with distant metastatic disease can also undergo resection for potential cure or symptom palliation because of the slow growth rate of many carcinoid tumors. In patients with the midgut carcinoid syndrome and bilobar hepatic disease we have performed primary surgery to relieve such symptoms as intestinal obstruction and ischemia, followed by successive embolizations of the hepatic arteries to reduce functional tumor burden in the liver. For optimal palliation, all patients with residual tumor were treated by octreotide. In a consecutive series of 64 patients with the midgut carcinoid syndrome we thus attained a 5-year survival rate of 70%. Fourteen of the patients underwent intentionally curative surgery (e.g., primary surgery followed by liver surgery). Of these patients, none died from their tumor disease during the period of study. The value of adjunctive interferon therapy is currently under evaluation.


Asunto(s)
Tumor Carcinoide/secundario , Tumor Carcinoide/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Antineoplásicos Hormonales/uso terapéutico , Terapia Combinada , Embolización Terapéutica , Arteria Hepática , Humanos , Neoplasias Intestinales/cirugía , Síndrome Carcinoide Maligno/cirugía , Octreótido/uso terapéutico , Cuidados Paliativos , Tasa de Supervivencia
11.
J Intern Med ; 238(2): 167-74, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7629485

RESUMEN

OBJECTIVE: It has been shown that the distribution of Na+ and Ca2+ in various cells is abnormal in patients with untreated primary hypertension, indicating an altered membrane permeability in these cells. This would activate certain ion pumps and thereby enhance ATP turnover. We investigated possible alterations in energy economy of skeletal muscle tissue. DESIGN: Skeletal muscle energetics were studied in vitro and in vivo in patients with untreated primary hypertension. Phosphocreatine (PCr), energy charge (EC) and total adenylate values were assessed. SETTING: The study was performed at the outpatient clinic of a general hospital and at a university clinical chemistry department and at a specialized bioenergetic laboratory. SUBJECTS: Altogether, 17 patients with untreated primary hypertension were examined together with matched, healthy and normotensive controls with normal body-mass index. MAIN OUTCOME MEASURES: Skeletal muscle biopsies were obtained from 10 patients and 10 controls for analysis of high energy phosphate compounds. Another seven patients were enrolled for in vivo NMR spectroscopy. RESULTS: We found a decrease of 30% (P < 0.01) of PCr content in the patients, whilst EC and total adenylates were unchanged. Nuclear magnetic resonance spectroscopy showed an abnormal decrease of PCr during exercise followed by a markedly slower regeneration of PCr during post-exercise recovery parallelled by a slower recovery of pH. This phenomenon was mirrored by a more pronounced decrease of ATP/Pi in patients during exercise and a slower recovery of ATP/Pi. CONCLUSION: The data are compatible with an increased ATP turnover in skeletal muscle cells of patients with untreated primary hypertension although ATP was favoured and kept at a normal resting level at the expense of the PCr store.


Asunto(s)
Hipertensión/metabolismo , Músculo Esquelético/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Prueba de Esfuerzo , Fuerza de la Mano , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores de Tiempo
12.
Acta Physiol Scand ; 154(4): 461-8, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7484172

RESUMEN

The effects of pre-treatment with mannitol and the iron chelator desferrioxamine on oxygen radical formation and glomerular and tubular function after ischaemia in the rabbit kidney were studied. Radicals were measured with ESR and spin trapping. At reperfusion after 60 min of renal ischaemia there was a significant increase in the production of free radicals in the venous effluent from the kidney. Administration of either mannitol or desferrioxamine given before ischaemia and before recirculation reduced the radical production significantly. The iron chelator appeared to be more effective. Glomerular function measured 48 h after reperfusion was significantly better after pretreatment with desferrioxamine and mannitol compared with mannitol alone. Tubular function did not differ between the two pre-treatment groups.


Asunto(s)
Deferoxamina/farmacología , Radicales Libres/metabolismo , Riñón/efectos de los fármacos , Riñón/fisiología , Manitol/farmacología , Daño por Reperfusión/tratamiento farmacológico , Animales , Riñón/irrigación sanguínea , Glomérulos Renales/irrigación sanguínea , Glomérulos Renales/efectos de los fármacos , Túbulos Renales/irrigación sanguínea , Túbulos Renales/efectos de los fármacos , Conejos
13.
Eur J Cancer ; 31A(5): 760-5, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7503906

RESUMEN

Physical exercise increases metabolic rate, and induces both adaptational biogenesis of mitochondria in skeletal muscle and an increase in antioxidant capacity. The onset of experimental anorexia and cachexia can be delayed by voluntary exercise. As skeletal muscle is the main target for cancer cachexia, we determined the levels of coenzymes Q9 and Q10 in skeletal muscle from tumour-bearing exercising rats, and compared them to those of sedentary tumour-bearers and controls. Both tumour-bearing groups had increased levels of coenzymes Q9 and Q10 in the anterior tibial muscle (P < 0.05 for exercised animals). In the soleus muscle, only the tumour-bearing exercising animals demonstrated an increase in the levels of both coenzymes (P < 0.05). In cardiac muscle, the presence of tumour and exercise reduced the levels of coenzymes below that of sedentary controls. Exercise counteracted the anaemia in the tumour-bearing host (P < 0.05). In conclusion, the increase in antioxidant capacity in skeletal muscle indicates a defence mechanism in the tumour-bearing hosts which is augmented by physical exercise.


Asunto(s)
Músculo Esquelético/enzimología , Miocardio/enzimología , Neoplasias Experimentales/enzimología , Condicionamiento Físico Animal/fisiología , Ubiquinona/metabolismo , Animales , Caquexia/enzimología , Coenzimas , Metabolismo Energético , Femenino , Ratas , Ratas Endogámicas WF , Ubiquinona/análogos & derivados
14.
Life Sci ; 56(6): 389-97, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7830500

RESUMEN

The effect of 32 mM ascorbate on the time courses of phosphocreatine (PCr), inorganic phosphate (Pi), adenosine triphosphate (ATP) and intracellular pH in rat skeletal muscle during ischemia and reperfusion was investigated in vivo using 31P nuclear magnetic resonance (NMR) spectroscopy. Ascorbate was administered intravenously prior to induction of ischemia and at the time of reperfusion. The changes in PCr/(PCr+Pi), ATP and pH were similar in the non-treated and in the treated groups during ischemia. PCr/(PCr+Pi) fell to < 10% and ATP to approximately 30% of the preischemic values after 4 hours of arrested circulation, and pH decreased considerably. Postischemic reperfusion was followed continuously for 150 minutes. At the time of reflow, treatment with ascorbate had an immediate, positive effect on the recovery of high energy phosphates and pH. The level of PCr/(PCr+Pi) was 86% higher (p < 0.001) and the ATP level was 40% higher (p < 0.001) in the treated group than in the control group by the end of the reperfusion period. The results provide in vivo evidence for a salvaging effect of ascorbate on ischemia-reperfusion injury in skeletal muscle, probably owing to its antioxidant function and other ancillary effects, mainly its provision of additional buffer capacity.


Asunto(s)
Ácido Ascórbico/farmacología , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/efectos de los fármacos , Daño por Reperfusión/prevención & control , Adenosina Trifosfato/metabolismo , Animales , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/uso terapéutico , Femenino , Concentración de Iones de Hidrógeno/efectos de los fármacos , Infusiones Intravenosas , Espectroscopía de Resonancia Magnética/métodos , Músculo Esquelético/metabolismo , Fosfatos/metabolismo , Fosfocreatina/efectos de los fármacos , Isótopos de Fósforo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo
15.
Scand J Plast Reconstr Surg Hand Surg ; 28(4): 261-8, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7899835

RESUMEN

The effect of ischaemia followed by reperfusion on energy metabolism was studied in human skeletal muscle after microsurgical free transfer. Muscle biopsy specimens from 11 patients treated by free muscle transfer for facial palsy, injury to an extremity, or scalp defect were studied. The biopsy specimens were taken during ischaemia and after one hour of reperfusion, respectively. They were analysed for ATP to uric acid and creatine phosphate by high pressure liquid chromatography. Ischaemia lasting one or two hours affected the energy metabolism of the muscle cell as evidenced by a 50% reduction in creatine phosphate; a 20% reduction in ATP and in the energy charge; a 100% increase in inosine monophosphate, and a 700% increase in hypoxanthine and xanthine. Reperfusion for one hour improved these figures somewhat, and induced the production of uric acid. Skeletal muscle can therefore tolerate ischaemia for up to two hours in the clinical situation without permanent damage to the tissues.


Asunto(s)
Músculo Esquelético/metabolismo , Músculo Esquelético/trasplante , Nucleótidos de Purina/metabolismo , Daño por Reperfusión/metabolismo , Adolescente , Adulto , Anciano , Cromatografía Líquida de Alta Presión , Metabolismo Energético/fisiología , Parálisis Facial/cirugía , Femenino , Humanos , Traumatismos de la Pierna/cirugía , Masculino , Microcirugia , Persona de Mediana Edad , Daño por Reperfusión/prevención & control , Cuero Cabelludo/cirugía , Colgajos Quirúrgicos , Factores de Tiempo
17.
Surg Oncol ; 3(2): 103-8, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7952389

RESUMEN

In an open study of unresectable liver tumours, isolated regional perfusion with hyperthermia and cytotoxic drugs has been tested in 29 patients. Four patients had primary hepatocellular cancer, 10 patients had metastases from malignant melanoma, remaining from breast cancer, colorectal cancer, midgut carcinoids and miscellaneous primaries. At laparotomy the proper hepatic artery and portal vein were canulated and connected to a pump oxygenator. The inferior vena cava was canulated with a triple lumen catheter (Perfufix) allowing for porto-caval shunting, drainage of lower body and renal veins to the heart and separate drainage of liver veins to the pump oxygenator. Liver perfusion was performed with a mean flow of 900 ml per min. Melphalan and cis-platinum 0.5 mg/kg body-weight were added to the perfusate for 1 h after liver temperature reached 40 degrees C. Four patients died within 30 days of perfusion due to multiple organ failure. These patients had more than 50% of liver volume occupied by cancer. All surviving patients developed reversible hepato- and renal toxicity. Partial tumour regression was registered in 20% of the patients. Five patients have survived more than three years. Hyperthermic liver perfusion is feasible but in patients with massive liver tumour, there is a significant risk of developing multiple organ failure.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia del Cáncer por Perfusión Regional/métodos , Hipertermia Inducida , Neoplasias Hepáticas/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioterapia del Cáncer por Perfusión Regional/efectos adversos , Cisplatino/administración & dosificación , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Melfalán/administración & dosificación , Persona de Mediana Edad , Insuficiencia Multiorgánica/etiología , Análisis de Supervivencia
18.
Am J Physiol ; 265(4 Pt 2): H1074-81, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8238394

RESUMEN

The perfused rat hindlimb preparation was used with a blood cell-free perfusate to investigate alterations in the purine nucleotide metabolism, flow rate, perfusion pressure, and venous excretion in response to ischemia and ischemia followed by reperfusion in skeletal muscle. The development of a physical hindrance during postischemic reperfusion, indicated by an increase in reperfusion pressure and a decrease in flow rate, coincided with a 90% decrease in phosphocreatine and a 50-70% reduction in total adenine nucleotide pool. The reflow impairment could not be explained by blood cell plugging of the capillaries. Washout of several metabolites was demonstrated during reperfusion. Hypoxanthine accumulated intracellularly during ischemia, and a substantial amount of uric acid was excreted into the venous effluent during reperfusion. The experimental data were fitted into a computer simulation model of the purine pathways. The model indicated that AMP deaminase was the predominant enzymatic pathway for the AMP degradation. It was demonstrated that ATP preferably accumulated as inosine-5'-monophosphate during ischemia and that xanthine oxidase was undetectable in skeletal muscle tissue homogenates. However, vascular endothelial cell xanthine oxidase activity responsible for a free radical-induced reperfusion injury could not be excluded.


Asunto(s)
Isquemia/metabolismo , Nucleótidos de Purina/metabolismo , Reperfusión , Nucleótidos de Adenina/metabolismo , Animales , Simulación por Computador , Femenino , Miembro Posterior/irrigación sanguínea , Inosina Monofosfato/metabolismo , Modelos Biológicos , Músculos/metabolismo , Perfusión , Fosfocreatina/metabolismo , Ratas , Ratas Sprague-Dawley , Xantina Oxidasa/metabolismo
19.
Acta Physiol Scand ; 147(3): 263-70, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8386425

RESUMEN

The effects of intracellular and extracellular superoxide dismutase and heparin administration on oxygen radical formation after ischaemia in the rabbit kidney were studied. Radicals were measured with ESR and spin trapping. At reperfusion after 60 min of renal ischaemia there was a significant increase in the production of free radicals in the venous effluent from the kidney. Administration of either intracellular superoxide dismutase or extracellular superoxide dismutase before ischaemia and before reperfusion prevented approximately 85% of the radical formation seen in the untreated control group. Administration of heparin 5 min before recirculation resulted in a 65% decrease in radical production compared to the control group.


Asunto(s)
Heparina/farmacología , Isquemia/metabolismo , Consumo de Oxígeno/fisiología , Circulación Renal/fisiología , Superóxido Dismutasa/farmacología , Animales , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres/metabolismo , Oxazoles , Consumo de Oxígeno/efectos de los fármacos , Conejos , Circulación Renal/efectos de los fármacos , Reperfusión
20.
Eur J Surg ; 159(3): 149-58, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8102889

RESUMEN

OBJECTIVE: To evaluate the results of treatment of a consecutive series of patients with adrenocortical carcinoma who presented during the six year period 1985 to 1991. DESIGN: Open study. SETTING: Departments of Surgery, Pathology, Endocrinology, and Clinical Chemistry, Sahlgren Hospital, Göteborg, Sweden. SUBJECTS: 10 consecutive patients, two with recurrent and eight with primary adrenocortical carcinoma. INTERVENTIONS: All patients were treated surgically. Two required preoperative embolisation of the tumour vessels to facilitate excision of particularly large tumours, and eight were given adjuvant treatment with mitotane (o,p'-DDD). RESULTS: At a median follow up of 1.5 years (range 3 months, to 21 years) 6 patients were alive with no radiological or biochemical signs of disease; 2 were alive, but with signs of recurrence (at 3 months and 6 years, respectively); and two had died of their disease (at 4 and 8 months, respectively). For the past two years all patients have had their urinary steroid profiles monitored by gas chromatography and mass spectrometry to detect recurrence of the tumour at the earliest possible stage. CONCLUSION: Operation is the treatment of choice for patients with adrenocortical carcinoma, particularly stages I-III. The role of mitotane as adjuvant treatment can be evaluated only in multicentre studies.


Asunto(s)
Tumor de Resto Suprarrenal/diagnóstico , Tumor de Resto Suprarrenal/terapia , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/metabolismo , Neoplasias de las Glándulas Suprarrenales/terapia , Tumor de Resto Suprarrenal/metabolismo , Tumor de Resto Suprarrenal/patología , Adulto , Anciano , Carcinoma/diagnóstico , Carcinoma/metabolismo , Carcinoma/terapia , Quimioterapia Adyuvante , Femenino , Humanos , Neoplasias Renales/diagnóstico , Neoplasias Renales/metabolismo , Neoplasias Renales/terapia , Masculino , Persona de Mediana Edad , Mitotano/uso terapéutico , Metástasis de la Neoplasia
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