RESUMEN
This was a single-centre, prospective study to assess the frequency of neurological complications and their impact on prolonged hospitalization in 137 liver transplant patients presenting between September 1997 and June 2010. Neurological complications were seen in 22 (16%) patients during their postoperative stay in the intensive care unit. Complications included new-onset, recurrent headache (five patients), generalized seizures (four patients), dysarthria (two patients), delirium with agitation (three patients), persistent flapping tremor (two patients), alteration in level of consciousness (three patients), central pontine myelinolysis (one patient), myopathy (one patient) and visual hallucinations (one patient). Seizures were associated with immunosuppressive drug toxicity (tacrolimus). Myopathy presenting as quadriplegia was diagnosed by muscle biopsy. The patient with central pontine myelinolysis lived in a persistent vegetative state for 2 years and died of pneumonia. In conclusion, neurological complications are frequently encountered after liver transplantation, and are an important cause of severe morbidity and prolonged intensive care unit and hospital stay.
Asunto(s)
Inmunosupresores/efectos adversos , Trasplante de Hígado/efectos adversos , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/patología , Complicaciones Posoperatorias , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Adulto JovenRESUMEN
BACKGROUND: Reduction in pulmonary exacerbations is an important efficacy endpoint for CF clinical studies. Powering exacerbation endpoints requires estimation of the future exacerbation incidence in CF study populations, but rates differ across the population. METHODS: We have estimated exacerbation rates for Epidemiologic Study of CF subpopulations stratified by age, FEV(1)% predicted, sex, weight-for-age percentile, respiratory signs and symptoms, and history of exacerbation and bacterial culture. Sample sizes required to attain 80% power to detect exacerbation reductions of 20% to 80% in 1:1 randomized studies of 3 to 12 month duration were determined. Exacerbation treatments with "any" antibiotic (new oral quinolone, new inhaled antibiotic, or intravenous (IV) antibiotic) and with IV antibiotics were studied. RESULTS: At all ages, decreased FEV(1), female sex, exacerbation history, and Pseudomonas aeruginosa culture history were associated with increased treatment for exacerbation. CONCLUSIONS: These data should assist investigators in the design of future CF exacerbation studies.
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Ensayos Clínicos como Asunto/estadística & datos numéricos , Fibrosis Quística/fisiopatología , Volumen Espiratorio Forzado , Pulmón/fisiopatología , Proyectos de Investigación/estadística & datos numéricos , Adolescente , Adulto , Niño , Fibrosis Quística/terapia , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Tamaño de la Muestra , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Rate of lung function decline (RLFD) (as FEV(1) percent predicted/yr) is a robust measure of CF therapeutic efficacy rarely used as a study endpoint, in part due to uncertainty of sample size requirements. METHODS: Sample size requirements for 1:1 randomizations to detect RLFD treatment effects from 20% to 80% were assessed in Epidemiologic Study of CF (ESCF) patients. Effects of measuring FEV(1) 1-4 times per year in studies of 1- to 4-year durations were assessed in 399 patients age ≥ 6 years with FEV(1) ≥ 70%. Impacts of inclusion/exclusion based on risk factors in 2369 ESCF patients were assessed over 1.5 years using semi-annual FEV(1) measures. RESULTS: Increasing study duration and exclusion of lower risk patients (e.g., no P. aeruginosa infection) both substantially reduced requirements. CONCLUSIONS: CF RLFD studies of 1.5 years in duration appear feasible provided that investigators account for the beneficial effects of subject inclusion/exclusion based on risk factors in power estimates.
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Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/fisiopatología , Volumen Espiratorio Forzado , Proyectos de Investigación , Adolescente , Adulto , Niño , Estudios de Factibilidad , Humanos , Pulmón/fisiopatología , Persona de Mediana Edad , Selección de Personal , Medición de Riesgo , Factores de Riesgo , Tamaño de la Muestra , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND AND OBJECTIVE: Previous studies in adults have demonstrated a clinically useful correlation between central venous pressure (CVP) and peripheral venous pressure (PVP). The current study prospectively compared CVP measurements from a central versus a peripheral catheter in kidney recipients during renal transplantation. METHODS: With ethics committee approval and informed consent, 30 consecutive kidney recipients were included in the study. We excluded patients who had significant valvular disease or clinically apparent left ventricular failure. For each of 30 patients, CVP and PVP were measured on five different occasions. The pressure tubing of the transducer system was connected to the distal lumen of the central or to the peripheral venous catheter for measurements following induction of anesthesia, after induction, 1 hour after induction, reperfusion of the kidney, and the end of the operation, yielding 150 hemodynamic data points. Each hemodynamic measurement included heart rate, mean arterial pressure, mean CVP, and mean PVP determined at end-expiration. RESULTS: The mean PVP was 13.5 +/- 1.8 mm Hg and the mean CVP was 11.0 +/- 1.5 mm Hg during surgery. The mean difference was 2.5 +/- 0.5 (P < .01). Repeated-measures analysis of variance indicated a highly significant relationship between PVP and CVP (P < .01) with a Pearson correlation coefficient of 0.97. CONCLUSION: Under the conditions of this study, PVP showed a consistently high agreement with CVP in the perioperative period among patients without significant cardiac dysfunction.
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Presión Venosa Central/fisiología , Trasplante de Riñón/fisiología , Presión Venosa/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Periodo Posoperatorio , Análisis de Regresión , ReperfusiónRESUMEN
BACKGROUND AND OBJECTIVE: Adding various opioids to the local anaesthetic solution administrated intrathecally improves the analgesic potency of spinal analgesia. The purpose of this study was to evaluate the efficacy and safety of intrathecal fentanyl 10 microg added to 15 mg hyperbaric ropivacaine in patients undergoing caesarean section under spinal anaesthesia. METHODS: Thirty-seven healthy, full-term parturients were randomly assigned into two groups: Group S (saline group, n=17) received 15 mg hyperbaric ropivacaine in 2.5 mL + 0.5 mL saline; Group F (fentanyl group, n=20) received 15 mg hyperbaric ropivacaine in 2.5 mL + 10 microg fentanyl in 0.5 mL, intrathecally. Characteristics of spinal block, intraoperative quality of spinal anaesthesia, time to first feeling of pain (complete analgesia), time to first request of analgesics postoperatively (effective analgesia), side-effects and fetal outcomes were evaluated. RESULTS: Regression of sensory block to L5 was significantly prolonged in the fentanyl group compared with the saline group (P = 0.001). Time to the first feeling of pain (130.6 +/- 15.8 min vs. 154.3 +/- 31.1 min; P = 0.008) and the first analgesic requirement (161.2 +/- 32.6 min vs. 213.0 +/- 29.3 min; P < 0.001) were significantly shorter in the saline group compared with the fentanyl group. Side-effects, umbilical arterial and venous blood gases did not differ between the groups. Apgar scores were similar in both groups and no infants had an Apgar score < or =7 at 5 min. CONCLUSIONS: The addition of fentanyl 10 microg, to hyperbaric ropivacaine 15 mg, for spinal anaesthesia increased the duration of analgesia in the early postoperative period in patients undergoing caesarean delivery.
Asunto(s)
Adyuvantes Anestésicos , Amidas , Anestesia Raquidea , Anestésicos Locales , Cesárea , Fentanilo , Adyuvantes Anestésicos/efectos adversos , Adulto , Amidas/efectos adversos , Anestesia Raquidea/efectos adversos , Anestésicos Locales/efectos adversos , Puntaje de Apgar , Análisis de los Gases de la Sangre , Método Doble Ciego , Femenino , Fentanilo/efectos adversos , Hemodinámica , Humanos , Inyecciones Espinales , Dimensión del Dolor , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Embarazo , Resultado del Embarazo , RopivacaínaRESUMEN
BACKGROUND: Brachial plexus block via the axillary approach is problematic in patients with limited arm mobility. In such cases, the infraclavicular approach may be a valuable alternative. The purpose of our study was to compare axillary and infraclavicular techniques for brachial plexus block in patients undergoing arm or forearm surgery. METHODS: After institutional approval and informed consent were obtained, 30 patients (ASA physical status I or II) scheduled for forearm and hand surgery under brachial plexus anesthesia were included in the study. Patients were randomly allocated into two groups. Brachial plexus block was performed via the axillary approach in the Group A patients and via the infraclavicular approach in the Group I patients using a peripheral nerve stimulator. All blocks were performed with a total dose of 40 ml 0.375% bupivacaine. RESULTS: In each nerve territory (radial, ulnar, median, and musculocutaneous), the mean values of the degree and the duration of the sensory block and motor block were not significantly different between the two groups (P > 0.05). Inadvertent vessel puncture was significantly more frequent in the axillary approach (P < 0.05). CONCLUSION: Brachial plexus block performed via the infraclavicular approach is as safe and effective as the axillary approach. Infraclavicular approach may be preferred to the axillary approach when the upper arm mobility is impaired or not desired.
Asunto(s)
Axila , Plexo Braquial , Bloqueo Nervioso/métodos , Adulto , Humanos , Persona de Mediana EdadRESUMEN
INTRODUCTION: The appropriate anesthesia for renal transplantation requires minimal toxicity for patients and for the transplanted organ, as well as sufficient pain relief and maintenance of vital functions. The aim of this study was to determine how the anesthetic technique influences the outcome in patients after renal transplantation in terms of preoperative and intraoperative hemodynamic changes and blood gas changes. METHODS: Fifty adult patients undergoing renal transplantation were randomly divided into two groups receiving standardized general anesthesia or combined spinal and epidural anesthesia. RESULTS: Demographically both groups were similar. Total anesthesia time (202 +/- 53 vs 186 +/- 37 minutes) and surgical time (191 +/- 52 vs 162 +/- 31 minutes) did not differ between the groups. The heart rate and systolic blood pressure values of the groups as measured before induction and 5, 15, 20, 30, as well as 60 minutes thereafter did not differ between the groups. Neither the frequency of bradycardia (four vs two) nor of hypotension (six vs four) during anesthesia differed between regional versus general anesthesia groups. CONCLUSION: Regional is an important alternative to general anesthesia during renal transplantation surgery in adult patients.
Asunto(s)
Anestesia Epidural , Anestesia General , Trasplante de Riñón/métodos , Adulto , Femenino , Supervivencia de Injerto , Hemodinámica , Humanos , Fallo Renal Crónico/cirugía , Trasplante de Riñón/fisiología , Tiempo de Internación , Masculino , Diálisis Renal , Resultado del TratamientoRESUMEN
BACKGROUND: Our purpose was to evaluate the effect of intrathecal fentanyl 25 microg added to 18 mg of 6 mg ml(-1) hyperbaric ropivacaine on the characteristics of subarachnoid block and postoperative pain relief in patients undergoing TURP surgery. METHODS: The patients were randomly assigned into two groups: Group S (saline group, n=16) received 3 ml of 18 mg hyperbaric ropivacaine + 0.5 ml saline--in total, a 3.5-ml volume intrathecally; and Group F (fentanyl group, n=15) received 3 ml of 18 mg hyperbaric ropivacaine + 0.5 ml of 25 microg fentanyl--in total, a 3.5-ml volume intrathecally. In both groups the onset and recovery times of the sensory block, degree and recovery times of the motor block and side-effects were recorded and statistically compared. RESULTS: There was no significant difference between the groups in achieving the highest level of sensory block, and in the times taken to reach the peak level. Regression to L1 was significantly prolonged in the fentanyl group compared with the saline group (P=0.004). Times to the first feeling of pain and the first analgesic requirement were significantly prolonged in the fentanyl group compared with the saline group (P=0.011 and P=0.016, respectively). The frequency of pruritus was significantly higher in the fentanyl group compared with the saline group (P=0.022). CONCLUSION: Addition of fentanyl 25 microg to hyperbaric ropivacaine 18 mg for spinal anesthesia in patients undergoing TURP may significantly improve the quality and prolong the duration of analgesia, without causing a substantial increase in the frequency of major side-effects.
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Amidas/uso terapéutico , Anestésicos Combinados/uso terapéutico , Anestésicos Intravenosos/uso terapéutico , Anestésicos Locales/uso terapéutico , Fentanilo/uso terapéutico , Resección Transuretral de la Próstata/métodos , Anestesia Raquidea/métodos , Anestésicos Intravenosos/administración & dosificación , Método Doble Ciego , Fentanilo/administración & dosificación , Humanos , Inyecciones Espinales/métodos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Dolor Postoperatorio/prevención & control , Ropivacaína , Cloruro de Sodio/administración & dosificación , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND AND OBJECTIVE: Our purpose was to evaluate the analgesic and sedative effects of intrathecal midazolam when added to spinal bupivacaine in patients undergoing perianal surgery under spinal anaesthesia. METHODS: Forty-four patients were randomly allocated into two equal groups: Group I (B) received hyperbaric bupivacaine 0.5% 2 mL + saline 0.9% 1 mL in a total volume of 3 mL intrathecally; Group II (BM) received hyperbaric bupivacaine 0.5% 2 mL + 1 mL of 2mg preservative-free midazolam in a total volume of 3 mL intrathecally. In both groups, the onset and recovery times of sensory block, the degree and recovery times of motor block as well as the sedation and visual analogue pain scores were recorded, and statistically compared. RESULTS: In Group BM, the postoperative visual analogue pain scores were significantly lower at the first 4 h (P < 0.05), the average time until the first dose of additional analgesic requirement was significantly longer (P < 0.05), and sedation scales were significantly higher (P < 0.05), compared to Group B. There were no statistically significant differences in the onset and the full recovery times of sensory and motor blocks in the two groups. CONCLUSION: The use of intrathecal midazolam combined with intrathecal bupivacaine produces a more effective and longer analgesia with a mild sedative effect in perianal surgery.
Asunto(s)
Canal Anal/cirugía , Anestésicos Intravenosos/uso terapéutico , Hipnóticos y Sedantes/uso terapéutico , Midazolam/uso terapéutico , Adulto , Anestesia Raquidea , Anestésicos Intravenosos/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Inyecciones Espinales , Masculino , Midazolam/administración & dosificación , Bloqueo Nervioso , Dimensión del Dolor , Dolor Postoperatorio/tratamiento farmacológicoRESUMEN
BACKGROUND AND OBJECTIVE: In recent human and animal studies, intrathecal administration of various doses of neostigmine produces analgesia without neurotoxicity. The aim was to examine the effects of intrathecal neostigmine and bupivacaine in patients undergoing perianal surgery under spinal anaesthesia. METHODS: The patients were randomly allocated into three groups of 15: Group 1 (controls) received hyperbaric bupivacaine 10 mg + dextrose 5%, 1 mL, to a total volume of 3 mL; Group 2 received hyperbaric bupivacaine 10 mg + neostigmine 25 microg in dextrose 5%, 1 mL, to a total volume of 3 mL; and Group 3 received hyperbaric bupivacaine 10 mg + neostigmine 50 microg in dextrose 5%, 1 mL, to a total volume of 3 mL. RESULTS: The onset of sensory block was significantly earlier for Group 2 and 3 patients compared with Group 1 patients (P < 0.05). The full time to recovery of motor block and sensory block was significantly longer in Group 3 compared with Group 1 (P < 0.05). In Group 3, the average time until the first dose of tramadol was longer than Group 1 (P < 0.05). The incidence rate of nausea and vomiting was significantly higher in Groups 2 and 3 than in Group 1 (P < 0.05). CONCLUSIONS: The use of intrathecal neostigmine as an analgesic drug in perianal surgery is unsatisfactory because of prolonged motor blockade and nausea.
Asunto(s)
Anestesia Local , Anestésicos Locales , Bupivacaína , Inhibidores de la Colinesterasa/administración & dosificación , Neostigmina/administración & dosificación , Canal Anal/cirugía , Anestésicos Combinados , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Bradicardia/etiología , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Inhibidores de la Colinesterasa/efectos adversos , Método Doble Ciego , Sinergismo Farmacológico , Hemorroides/cirugía , Humanos , Inyecciones Espinales , Náusea/etiología , Neostigmina/efectos adversos , Resultado del TratamientoRESUMEN
OBJECTIVES: Previous studies have revealed an increase in several forms of phospholipase A2 activity associated with cell injury, but the secretory form of phospholipase A2 has not previously been studied in neurological disorders. We investigated the influence of seizures on secretory phospholipase A2 and phospholipid breakdown in synaptosome fractions prepared from rat hippocampus, cortex and cerebellum in pentylenetetrazol-induced epilepsy. MATERIAL AND METHODS: Secretory phospholipase A2 concentration was measured by a photometric enzyme immunoassay. The synaptosomes underwent extraction, and the phospholipids fractions for phosphatidylcholine, phosphatidylethanolamine and lysophosphatidylcholine were recovered from the thin layer chromatography plates. The amount of each phospholipid was quantified using the amount of recovered phosphate in each phospholipid spot. RESULTS: Secretory phospholipase A2 concentration was found to be significantly higher in the epileptic group when compared with the control group. The amounts of phospholipids were found to be highly variable in different brain regions. CONCLUSION: Our results suggest that epileptic seizures enhanced phospholipid breakdown and induced alterations in the distribution of phospholipids in different brain regions.
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Membrana Celular/enzimología , Cerebelo/enzimología , Corteza Cerebral/enzimología , Epilepsia/enzimología , Hipocampo/enzimología , Neuronas/enzimología , Fosfolipasas A/análisis , Fosfolipasas A/metabolismo , Fosfolípidos/análisis , Sinaptosomas/enzimología , Animales , Membrana Celular/metabolismo , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Convulsivantes/efectos adversos , Modelos Animales de Enfermedad , Epilepsia/inducido químicamente , Femenino , Hipocampo/metabolismo , Lisofosfatidilcolinas/análisis , Neuronas/metabolismo , Pentilenotetrazol/efectos adversos , Fosfatidilcolinas/análisis , Fosfatidiletanolaminas/análisis , Fosfolipasas A2 , Ratas , Ratas Wistar , Sinaptosomas/metabolismoRESUMEN
Anaphylaxis is one of the most life-threatening emergencies that can occur in the perioperative period. Multiple agents can be responsible, and nonallergic reactions can mimic anaphylaxis. Developing a therapeutic plan for the acute therapy of anaphylaxis is important. Prompt recognition with appropriate and aggressive therapy can help avoid a disastrous outcome.
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Anafilaxia/diagnóstico , Anafilaxia/fisiopatología , Anestesia/efectos adversos , Monitoreo Fisiológico , Anafilaxia/terapia , Humanos , Hipotensión/tratamiento farmacológico , Terapia por Inhalación de OxígenoRESUMEN
1. The effects of halothane and isoflurane anesthesia on red blood cell (RBC) deformability, lipid peroxidation and antioxidant enzymes were tested in rabbits. 2. RBC transit time was significantly increased to 2.12 +/- 0.07 msec after 1-hr halothane anesthesia preceded by 6 mg/kg pentobarbital injections from 1.98 +/- 0.07 msec preanesthesia value (p < 0.05). Thiobarbituric acid-reactive substances also were increased significantly, being 23.35 +/- 2.75 nmol/gHb and 33.11 +/- 5.34 nmol/gHb before and after anesthesia, respectively (p < 0.05). 3. Under halothane anesthesia without prior pentobarbital injection or under isoflurane anesthesia with or without pentobarbital injection, no significant alterations were observed in these parameters. 4. RBC superoxide dismutase activity was decreased in the group anesthetized with the pentobarbital-halothane combination. The impaired RBC deformability and increased oxidant damage might be related to the free radical formation during the metabolism of halothane. Pentobarbital can potentiate this effect either by inducing cytochrome P-450 or by altering antioxidant defense. 5. Alterations in RBC mechanical properties may contribute to the tissue perfusion problems that develop after surgery under general anesthesia.
Asunto(s)
Anestésicos por Inhalación/farmacología , Deformación Eritrocítica/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Halotano/farmacología , Isoflurano/farmacología , Estrés Oxidativo/efectos de los fármacos , Adyuvantes Anestésicos/farmacología , Animales , Peroxidación de Lípido/efectos de los fármacos , Pentobarbital/farmacología , Conejos , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
1. The in vitro effects of cumene hydroperoxide and t-butyl hydroperoxide on intact human erythrocyte membrane (Na(+)-K+)ATPase activities have been studied. 2. (Na(+)-K+)ATPase activities on erythrocyte membranes decreased in agreement with the results of chemiluminescence experiments. 3. Our results demonstrated that the organic hydroperoxides inhibit the activity of (Na(+)-K+) ATPase enzyme and that the antioxidants used prevent this inhibition.
Asunto(s)
Antiinfecciosos Locales/farmacología , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Hidroxitolueno Butilado/farmacología , Eritrocitos/enzimología , Peróxido de Hidrógeno/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , HumanosRESUMEN
Recently, it has been suggested that bilirubin may act as a potent biological chain-breaking antioxidant. To observe the effects of free bilirubin on antioxidant reactions in cumene hydroperoxide-treated erythrocytes (15 g hemoglobin/dl), we added bilirubin at four different concentrations (0.5, 1, 5, and 10 mg/dl). We measured the thiobarbituric acid-reactive substance and reduced glutathione levels, and some antioxidant enzyme activities, namely superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase. Thiobarbituric acid-reactive substance and chemiluminescent signals decreased during the incubation. Superoxide dismutase activities also decreased but not as much as in the control group. Glucose-6-phosphate dehydrogenase activities and reduced glutathione levels increased, but catalase activities remained the same as the control group. Our results suggest that bilirubin--in the concentrations we have used--partially prevented the oxidant effects of cumene hydroperoxide.
Asunto(s)
Derivados del Benceno/farmacología , Bilirrubina/farmacología , Eritrocitos/enzimología , Peroxidación de Lípido/efectos de los fármacos , Oxidantes/farmacología , Antioxidantes/metabolismo , Catalasa/metabolismo , Eritrocitos/efectos de los fármacos , Glucosafosfato Deshidrogenasa/metabolismo , Glutatión/metabolismo , Hemólisis , Humanos , Mediciones Luminiscentes , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
Erythrocytes and hemolysates from 10 normal and 10 glucose-6-phosphate dehydrogenase-deficient individuals were incubated with cumene hydroperoxide, and free radical-induced lipid peroxidation was monitored by chemiluminescence. Chemiluminescence intensities in erythrocytes of normal and deficient subjects were similar in the presence or absence of glucose-6-phosphate dehydrogenase substrates. Hemolysates of normal and deficient subjects also showed similar chemiluminescence in the absence of substrates. However, with the addition of substrates to the incubation medium, deficient hemolysates reached maximum chemiluminescence intensity within a shorter period, and maximum values were higher than in normal hemolysates. We believe this offers a new means of detection of glucose-6-phosphate dehydrogenase-deficient patients.
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Eritrocitos/fisiología , Deficiencia de Glucosafosfato Deshidrogenasa/fisiopatología , Peroxidación de Lípido/fisiología , Estrés Oxidativo/fisiología , Derivados del Benceno , Deficiencia de Glucosafosfato Deshidrogenasa/sangre , Deficiencia de Glucosafosfato Deshidrogenasa/inducido químicamente , Hemólisis/fisiología , Humanos , Mediciones Luminiscentes , Masculino , Oxidantes , Valores de Referencia , Especificidad por SustratoRESUMEN
To obtain further insight into the role of erythrocyte antioxidant systems in the development of atherosclerosis, intraerythrocyte enzyme activities and selenium levels in erythrocytes were determined in 37 patients with angiographically proved coronary artery stenosis and 15 subjects with normal coronary angiograms as controls. In a preliminary study, the enzymatic activities of glucose-6-phosphate dehydrogenase (G6PD), glutathione reductase (GR) and selenium-dependent glutathione peroxidase (Se-GPx) were measured in both venous and arterial blood samples obtained from patients before angiography. The data of the preliminary study, which showed that only the Se-GPx decreased in the patients, led us to concentrate on the Se-GPx and Se levels to determine the changes in these variables. Our results showed that there was a decrease in both the activity of Se-GPx and Se levels in erythrocytes parallel to the increase in the severity of coronary artery disease. It was concluded that these parameters might be used as determinants in the assessment of the severity of the disease.
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Enfermedad de la Arteria Coronaria/enzimología , Eritrocitos/enzimología , Glutatión Peroxidasa/metabolismo , Selenio/sangre , Adulto , Anciano , Antioxidantes/metabolismo , Enfermedad Coronaria/enzimología , Femenino , Glucosafosfato Deshidrogenasa/metabolismo , Glutatión Reductasa/metabolismo , Humanos , Masculino , Persona de Mediana EdadRESUMEN
We studied the effect of cumene hydroperoxide, t-butyl hydroperoxide, and hydrogen peroxide on intact healthy human erythrocytes (15 g hemoglobin/dl) using chemiluminescence to monitor peroxidation. We measured the chemiluminescence spectrum, the process of hemolysis, the pH shift, and absorbance spectrum during the incubation with chemicals producing oxidative stress. Maximum chemiluminescence was reached with cumene hydroperoxide at about 50 min, but with t-butyl hydroperoxide at 100 min. The effect of organic hydroperoxide was concentration dependent, whereas the effect of hydrogen peroxide was independent of concentration. Peroxides induced hemolysis after 30 min. The pH shift to alkaline was observed in the first 20-min period. Incubation with organic hydroperoxides induced a decrease in absorption at 580, 545, and 345 nm. Hydrogen peroxide induced a decrease in the same period of time but this returned to the normal range by 120 min. There was no change in absorption at 420 nm with any of the peroxidative agents. Our results suggest that low-level chemiluminescence is a useful model for studying hydroperoxide-induced peroxidation in human erythrocytes.
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Derivados del Benceno/farmacología , Eritrocitos/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Peroxidación de Lípido/efectos de los fármacos , Peróxidos/farmacología , Especies Reactivas de Oxígeno/fisiología , Antioxidantes/farmacología , Eritrocitos/metabolismo , Hemólisis/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Mediciones Luminiscentes , Valores de Referencia , Espectrofotometría , terc-ButilhidroperóxidoRESUMEN
The extent of lipoprotein glycation was assessed in 82 patients diagnosed as diabetes mellitus type II. Glycated lipoprotein levels in serum were determined by agarose gel film electrophoresis in 48 non-diabetic control subjects, 56 diabetics with complications and 26 diabetics with no complications. All glycated lipoproteins were higher in the patients when the diabetics were compared to the control group, but glycated very low-density lipoprotein (VLDL) was the only glycated lipoprotein fraction that was observed to be higher in the diabetic patients with complications compared to the patients without complications (P < 0.01). Triglycerides and VLDL-cholesterol were also increased in the diabetics, but there was no significant difference in these variables when the patients without complications were compared to the control subjects. There was no difference in total cholesterol and low-density lipoprotein (LDL)-cholesterol levels of the diabetic patients compared to the controls.
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Diabetes Mellitus Tipo 2/sangre , Productos Finales de Glicación Avanzada/sangre , Lipoproteínas VLDL/sangre , Lipoproteínas/sangre , Colesterol/sangre , Diabetes Mellitus Tipo 2/complicaciones , Electroforesis en Gel de Agar , Femenino , Fructosamina , Glicosilación , Hexosaminas/sangre , Humanos , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Albúmina Sérica/metabolismo , Triglicéridos/sangre , Albúmina Sérica GlicadaRESUMEN
We used a new and remarkably simple method to examine the extent of in vivo lipoprotein glycation in type II diabetic patients with atherosclerosis and diabetic patients with no complications. Serum glycated lipoprotein levels were determined by agarose gel film electrophoresis in 48 non-diabetic control subjects and 39 diabetic patients, of whom 26 had no complications and 13 had atherosclerotic heart disease. Fasting serum glucose, glycohemoglobin and serum fructosamine concentrations (indicators of glycemia) and total cholesterol, triglyceride, low-density lipoprotein-, very low-density lipoprotein- and high-density lipoprotein-cholesterol concentrations and the low-density lipoprotein/high-density lipoprotein ratio (serum lipid profile) were also determined in the control and diabetic subjects. Glycated low-density lipoprotein and very low-density lipoprotein concentrations were significantly increased in diabetic patients compared with controls; but only glycated very low-density lipoprotein was significantly increased in atherosclerotic patients compared with diabetics without complications. The lipid profile parameters were not significantly increased in patients compared with controls. In diabetics, especially those with poorly controlled hyperglycemia and atherosclerosis, glycation of lipoprotein fractions might be more important than serum lipid and lipoprotein abnormalities. The significant correlation between atherosclerosis and glycated very low-density lipoprotein, suggests that very low-density lipoprotein glycation could be responsible for the development of atherosclerosis in diabetes.