156 resultados para 7 (2 hydroxyethyl)guanine


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The relationship between platelet count and outcome in patients with acute venous thromboembolism (VTE) has not been consistently explored. RIETE is an ongoing registry of consecutive patients with acute VTE. We categorised patients as having very low- (<80,000/µl), low- (80,000/µl to 150,000/µl), normal- (150,000/µl to 300,000/µl), high- (300,000/µl to 450,000/µl), or very high (>450,000/µl) platelet count at baseline, and compared their three-month outcome. As of October 2012, 43,078 patients had been enrolled in RIETE: 21,319 presenting with pulmonary embolism and 21,759 with deep-vein thrombosis. In all, 502 patients (1.2%) had very low-; 5,472 (13%) low-; 28,386 (66%) normal-; 7,157 (17%) high-; and 1,561 (3.6%) very high platelet count. During the three-month study period, the recurrence rate was: 2.8%, 2.2%, 1.8%, 2.1% and 2.2%, respectively; the rate of major bleeding: 5.8%, 2.6%, 1.7%, 2.3% and 4.6%, respectively; the rate of fatal bleeding: 2.0%, 0.9%, 0.3%, 0.5% and 1.2%, respectively; and the mortality rate: 29%, 11%, 6.5%, 8.8% and 14%, respectively. On multivariate analysis, patients with very low-, low-, high- or very high platelet count had an increased risk for major bleeding (odds ratio [OR]: 2.70, 95% confidence interval [CI]: 1.85-3.95; 1.43 [1.18-1.72]; 1.23 [1.03-1.47]; and 2.13 [1.65-2.75]) and fatal bleeding (OR: 3.70 [1.92-7.16], 2.10 [1.48-2.97], 1.29 [0.88-1.90] and 2.49 [1.49-4.15]) compared with those with normal count. In conclusion, we found a U-shaped relationship between platelet count and the three-month rate of major bleeding and fatal bleeding in patients with VTE.

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PURPOSE: An optimal target for glucose control in ICU patients remains unclear. This prospective randomized controlled trial compared the effects on ICU mortality of intensive insulin therapy (IIT) with an intermediate glucose control. METHODS: Adult patients admitted to the 21 participating medico-surgical ICUs were randomized to group 1 (target BG 7.8-10.0 mmol/L) or to group 2 (target BG 4.4-6.1 mmol/L). RESULTS: While the required sample size was 1,750 per group, the trial was stopped early due to a high rate of unintended protocol violations. From 1,101 admissions, the outcomes of 542 patients assigned to group 1 and 536 of group 2 were analysed. The groups were well balanced. BG levels averaged in group 1 8.0 mmol/L (IQR 7.1-9.0) (median of all values) and 7.7 mmol/L (IQR 6.7-8.8) (median of morning BG) versus 6.5 mmol/L (IQR 6.0-7.2) and 6.1 mmol/L (IQR 5.5-6.8) for group 2 (p < 0.0001 for both comparisons). The percentage of patients treated with insulin averaged 66.2 and 96.3%, respectively. Proportion of time spent in target BG was similar, averaging 39.5% and 45.1% (median (IQR) 34.3 (18.5-50.0) and 39.3 (26.2-53.6)%) in the groups 1 and 2, respectively. The rate of hypoglycaemia was higher in the group 2 (8.7%) than in group 1 (2.7%, p < 0.0001). ICU mortality was similar in the two groups (15.3 vs. 17.2%). CONCLUSIONS: In this prematurely stopped and therefore underpowered study, there was a lack of clinical benefit of intensive insulin therapy (target 4.4-6.1 mmol/L), associated with an increased incidence of hypoglycaemia, as compared to a 7.8-10.0 mmol/L target. (ClinicalTrials.gov # NCT00107601, EUDRA-CT Number: 200400391440).

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This study examined the effects of intermittent hypoxic training (IHT) on skeletal muscle monocarboxylate lactate transporter (MCT) expression and anaerobic performance in trained athletes. Cyclists were assigned to two interventions, either normoxic (N; n = 8; 150 mmHg PIO2) or hypoxic (H; n = 10; 764;3000 m, 100 mmHg PIO2) over a three week training (5×1 h-1h30.week-1) period. Prior to and after training, an incremental exercise test to exhaustion (EXT) was performed in normoxia together with a 2 min time trial (TT). Biopsy samples from the vastus lateralis were analyzed for MCT1 and MCT4 using immuno-blotting techniques. The peak power output (PPO) increased (p<0.05) after training (7.2% and 6.6% for N and H, respectively), but VO2max showed no significant change. The average power output in the TT improved significantly (7.3% and 6.4% for N and H, respectively). No differences were found in MCT1 and MCT4 protein content, before and after the training in either the N or H group. These results indicate there are no additional benefits of IHT when compared to similar normoxic training. Hence, the addition of the hypoxic stimulus on anaerobic performance or MCT expression after a three-week training period is ineffective.

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Background. Des études précédentes ont démontré l'efficacité et la tolérance de l'adalimumab chez les patients avec maladie de Crohn modérée ou sévère. Les patients qu'on rencontre dans la pratique quotidienne peuvent être différents des patients rigoureusement sélectionnés dans les études contrôlées.But. Dans ce travail, nous résumons notre expérience avec l'adalimumab durant une période de 3 ans.Méthodes. Nous avons analysé rétrospectivement les dossiers de 55 patients atteints d'une maladie de Crohn modérée ou sévère et traités par adalimumab dans les hôpitaux universitaires de Bâle, Zurich, Genève et Lausanne, ainsi que dans un cabinet médical à Olten. Les informations collectées étaient les suivantes : données démographiques, localisation, phénotype et durée de la maladie, traitements chirurgicaux précédents, traitements précédents par anti-TNF alpha ou immunosuppresseur, le traitement concomitant et l'activité de la maladie à la « baseline » et durant le traitement. La sévérité de la maladie à l'inclusion a été établie en utilisant le score Harvey- Bradshaw Index (HBI). Durant le traitement, la rémission a été définie avec un HBI<4 et la réponse comme une réduction de l'HBI de plus de 3 points. L'analyse de régression logistique univariée a été utilisée pour déterminer si les variables étudiées étaient associées à la réponse ou à la rémission durant le traitement.Résultats. L'âge moyen des patients a été de 37.5 ± 11.4 ans et la durée moyenne de maladie à été de 12.7 ans. 29 des 55 patients étaient des fumeurs. Le traitement d'induction a été effectué chez 31 patients avec l'adalimumab en sous-cutané 160 mg à la semaine 0 et 80 mg à la semaine 2 et chez 24 patients avec 80 mg à la semaine 0 et 40 mg à la semaine 2. Le traitement d'entretien a été de 40 mg en sous-cutané toutes les 2 semaines. 13 patients (23.6%) ont nécessité l'augmentation de la dose d'adalimumab pour maintenir la rémission ou la réponse.Le taux de rémission et de réponse à la semaine 4-6 était de 52.7%, respectivement 83.6%. La rémission a été maintenue aux semaines 12, 24 et 52 chez 89.6%, 72.4%, respectivement 44.7% des patients. Le taux de rémission et de réponse n'a pas été influencé par le tabagisme, la location ou la durée de la maladie, la dose totale donnée durant le premier mois de traitement, la dose d'adalimumab par kilogramme-corps ou par le traitement précédent par infliximab. La rémission à la semaine 4-6 a été significativement plus élevée chez les patients intolérants à l'infliximab comparativement à ceux qui avaient perdu la réponse à l'infliximab (78.9% vs 42.1%, p=0.02). Le traitement par adalimumab a été bien toléré. Les effets secondaires les plus signalés ont été : la douleur au site d'injection (10.9%), l'asthénie (9%) et des infections (7.2%).Conclusions. L'adalimumab a démontré une bonne efficacité et tolérance dans la pratique quotidienne chez les patients avec une maladie de Crohn modérée ou sévère.

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Activation of the hepatoportal glucose sensors by portal glucose infusion leads to increased glucose clearance and induction of hypoglycemia. Here, we investigated whether glucagon-like peptide-1 (GLP-1) could modulate the activity of these sensors. Mice were therefore infused with saline (S-mice) or glucose (P-mice) through the portal vein at a rate of 25 mg/kg. min. In P-mice, glucose clearance increased to 67.5 +/- 3.7 mg/kg. min as compared with 24.1 +/- 1.5 mg/kg. min in S-mice, and glycemia decreased from 5.0 +/- 0.1 to 3.3 +/- 0.1 mmol/l at the end of the 3-h infusion period. Coinfusion of GLP-1 with glucose into the portal vein at a rate of 5 pmol/kg. min (P-GLP-1 mice) did not increase the glucose clearance rate (57.4 +/- 5.0 ml/kg. min) and hypoglycemia (3.8 +/- 0.1 mmol/l) observed in P-mice. In contrast, coinfusion of glucose and the GLP-1 receptor antagonist exendin-(9-39) into the portal vein at a rate of 0.5 pmol/kg. min (P-Ex mice) reduced glucose clearance to 36.1 +/- 2.6 ml/kg. min and transiently increased glycemia to 9.2 +/- 0.3 mmol/l at 60 min of infusion before it returned to the fasting level (5.6 +/- 0.3 mmol/l) at 3 h. When glucose and exendin-(9-39) were infused through the portal and femoral veins, respectively, glucose clearance increased to 70.0 +/- 4.6 ml/kg. min and glycemia decreased to 3.1 +/- 0.1 mmol/l, indicating that exendin-(9-39) has an effect only when infused into the portal vein. Finally, portal vein infusion of glucose in GLP-1 receptor(-/-) mice failed to increase the glucose clearance rate (26.7 +/- 2.9 ml/kg. min). Glycemia increased to 8.5 +/- 0.5 mmol/l at 60 min and remained elevated until the end of the glucose infusion (8.2 +/- 0.4 mmol/l). Together, our data show that the GLP-1 receptor is part of the hepatoportal glucose sensor and that basal fasting levels of GLP-1 sufficiently activate the receptor to confer maximum glucose competence to the sensor. These data demonstrate an important extrapancreatic effect of GLP-1 in the control of glucose homeostasis.

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Compliance with antihypertensive therapy was monitored for three months using an electronic medication dispenser in 35 patients remaining hypertensive despite the once-daily administration of a blood pressure lowering drug (either as monotherapy or as fixed-dose combination therapy). During the monitoring of compliance, the treatment was unchanged but blood pressure decreased significantly (p < 0.001) from 167.9/100.4 +/- 16.3/7.2 mmHg (mean +/- SD) to 152.5/90.9 +/- 20.9/11.5 mmHg. The percentage of days with one opening per day was 80.8 +/- 20.5. Thus, discussing with the patient about compliance with the prescribed drug regimen and monitoring compliance for a few months allows better control of blood pressure. This most likely reflects increased compliance with antihypertensive drug therapy.

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BACKGROUND: Denosumab is a fully human monoclonal antibody to the receptor activator of nuclear factor-kappaB ligand (RANKL) that blocks its binding to RANK, inhibiting the development and activity of osteoclasts, decreasing bone resorption, and increasing bone density. Given its unique actions, denosumab may be useful in the treatment of osteoporosis. METHODS: We enrolled 7868 women between the ages of 60 and 90 years who had a bone mineral density T score of less than -2.5 but not less than -4.0 at the lumbar spine or total hip. Subjects were randomly assigned to receive either 60 mg of denosumab or placebo subcutaneously every 6 months for 36 months. The primary end point was new vertebral fracture. Secondary end points included nonvertebral and hip fractures. RESULTS: As compared with placebo, denosumab reduced the risk of new radiographic vertebral fracture, with a cumulative incidence of 2.3% in the denosumab group, versus 7.2% in the placebo group (risk ratio, 0.32; 95% confidence interval [CI], 0.26 to 0.41; P<0.001)--a relative decrease of 68%. Denosumab reduced the risk of hip fracture, with a cumulative incidence of 0.7% in the denosumab group, versus 1.2% in the placebo group (hazard ratio, 0.60; 95% CI, 0.37 to 0.97; P=0.04)--a relative decrease of 40%. Denosumab also reduced the risk of nonvertebral fracture, with a cumulative incidence of 6.5% in the denosumab group, versus 8.0% in the placebo group (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01)--a relative decrease of 20%. There was no increase in the risk of cancer, infection, cardiovascular disease, delayed fracture healing, or hypocalcemia, and there were no cases of osteonecrosis of the jaw and no adverse reactions to the injection of denosumab. CONCLUSIONS: Denosumab given subcutaneously twice yearly for 36 months was associated with a reduction in the risk of vertebral, nonvertebral, and hip fractures in women with osteoporosis. (ClinicalTrials.gov number, NCT00089791.)

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BACKGROUND/AIMS: One of the causes of uncontrolled secondary hyperparathyroidism (sHPT) is patient's poor drug adherence. We evaluated the clinical benefits of an integrated care approach on the control of sHPT by cinacalcet. METHODS: Prospective, randomized, controlled, multicenter, open-label study. Fifty hemodialysis patients on a stable dose of cinacalcet were randomized to an integrated care approach (IC) or usual care approach (UC). In the IC group, cinacalcet adherence was monitored using an electronic system. Results were discussed with the patients in motivational interviews, and drug prescription adapted accordingly. In the UC group, drug adherence was monitored, but results were not available. RESULTS: At six months, 84% of patients in the IC group achieved recommended iPTH targets versus 55% in the UC group (P = 0.04). The mean cinacalcet taking adherence improved by 10.8% in the IC group and declined by 5.3% in the UC group (P = 0.02). Concomitantly, the mean dose of cinacalcet was reduced by 7.2 mg/day in the IC group and increased by 6.4 mg/day in the UC group (P = 0.03). CONCLUSIONS: The use of a drug adherence monitoring program in the management of sHPT in hemodialysis patients receiving cinacalcet improves drug adherence and iPTH control and allows a reduction in the dose of cinacalcet.

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Objective: To establish if hyperglycaemia and cardiac Troponin I (cTnI) after congenital heart surgery on cardiopulmonary bypass in children could predict outcome in intensive care unit. Methods: retrospective cohort study including 274 children (mean age 4.6 years; range 0 - 17 years-old). CTnI and glucose values were retrieved from our database. Integrated values (area under the curve (AUC)) were calculated for evaluation of sustained hyperglycaemia and then normalised per hour (48h-Gluc/h). Maximal cTnI, fi rst glucose value (Gluc1) and 48h-Gluc/h were then correlated with duration of mechanical ventilation, ICU stay and mortality using cut-off values. Results: The mean duration of mechanical ventilation was 5.1 ± 7.2 days and ICU stay was 11.0 ± 13.3 days, 11 patients (3.9%) died. Hyperglycaemia (>6.1 mmol/l) was present in 68% of children at admission and was sustained in 85% for 48 hours. The mean value of Gluc1 (7.3 ± 2.7 vs. 11.8 ± 6.4 mmol/l, p < 0.0001), 48h-Gluc/h (7.4 ± 1.4 vs. 9.9 ± 4.6 mmol/l/h, p < 0.0001) and cTnI max (16.7 ± 21.8 vs. 59.2 ± 41.4 mcg/l, p < 0.0001) were signifi cantly lower in survivors vs. non survivors. Cut-off values and odds ratio are summarised in Table 1. Analyses for duration of mechanical ventilation and for length of stay in ICU are depicted in Table 2. Conclusions: Hyperglycaemia is frequent after cardiopulmonary bypass and sustained in the fi rst 48 hours. Admission glycaemia and cTnI max are associated with a high risk of mortality, prolonged duration of mechanical ventilation and prolonged length of stay in ICU.

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Neuropeptide Y (NPY) is a vasoconstrictor peptide possibly involved in the regulation of renal sodium handling and renin release. This investigation was undertaken to assess in conscious normotensive rats the acute effects of a non-pressor dose of NPY on renal plasma flow, glomerular filtration rate, sodium excretion and plasma renin activity. Experiments were also performed during concomitant beta-adrenoceptor stimulation with isoproterenol. NPY per se had no effect on the studied parameters. Renal plasma flow was increased by isoproterenol and was significantly higher when the beta-adrenoceptor stimulant was infused alone (13.4 +/- 2.1 ml/min, p < 0.05, mean +/- SEM) that when administered together with NPY (7.2 +/- 2.0 ml/min). This was also true for glomerular filtration rate (3.3 +/- 0.3 vs. 1.8 +/- 0.3 ml/min, p < 0.01) and plasma renin activity (6.3 +/- 1.7 vs. 2.1 +/- 0.4 ng Ang I/ml/h, p < 0.05). Our data however do not allow to deduce whether the inhibitory effect of NPY on isoproterenol-induced renin release is mediated by changes in intrarenal hemodynamics or a direct effect on juxtaglomerular cells.

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OBJECTIVE: To evaluate the relative importance of increased lactate production as opposed to decreased utilization in hyperlactatemic patients, as well as their relation to glucose metabolism. DESIGN: Prospective observational study. SETTING: Surgical intensive care unit of a university hospital. PATIENTS: Seven patients with severe sepsis or septic shock, seven patients with cardiogenic shock, and seven healthy volunteers. INTERVENTIONS: C-labeled sodium lactate was infused at 10 micromol/kg/min and then at 20 micromol/kg/min over 120 mins each. H-labeled glucose was infused throughout. MEASUREMENTS AND MAIN RESULTS: Baseline arterial lactate was higher in septic (3.2 +/- 2.6) and cardiogenic shock patients (2.8 +/- 0.4) than in healthy volunteers (0.9 +/- 0.20 mmol/L, p < .05). Lactate clearance, computed using pharmacokinetic calculations, was similar in septic, cardiogenic shock, and controls, respectively: 10.8 +/- 5.4, 9.6 +/- 2.1, and 12.0 +/- 2.6 mL/kg/min. Endogenous lactate production was determined as the initial lactate concentration multiplied by lactate clearance. It was markedly enhanced in the patients (septic 26.2 +/- 10.5; cardiogenic shock 26.6 +/- 5.1) compared with controls (11.2 +/- 2.7 micromol/kg/min, p < .01). C-lactate oxidation (septic 54 +/- 25; cardiogenic shock 43 +/- 16; controls 65 +/- 15% of a lactate load of 10 micromol/kg/min) and transformation of C-lactate into C-glucose were not different (respectively, 15 +/- 15, 9 +/- 18, and 10 +/- 7%). Endogenous glucose production was markedly increased in the patients (septic 14.8 +/- 1.8; cardiogenic shock 15.0 +/- 1.5) compared with controls (7.2 +/- 1.1 micromol/kg/min, p < .01) and was not influenced by lactate infusion. CONCLUSIONS: In patients suffering from septic or cardiogenic shock, hyperlactatemia was mainly related to increased production, whereas lactate clearance was similar to healthy subjects. Increased lactate production was concomitant to hyperglycemia and increased glucose turnover, suggesting that the latter substantially influences lactate metabolism during critical illness.

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Near infrared spectroscopy (NIRS) is a non-invasive method of estimating the haemoglobin concentration changes in certain tissues. It is frequently used to monitor oxygenation of the brain in neonates. At present it is not clear whether near infrared spectroscopy of other organs (e.g. the liver as a corresponding site in the splanchnic region, which reacts very sensitively to haemodynamic instability) provides reliable values on their tissue oxygenation. The aim of the study was to test near infrared spectroscopy by measuring known physiologic changes in tissue oxygenation of the liver in newborn infants during and after feeding via a naso-gastric tube. The test-retest variability of such measurements was also determined. On 28 occasions in 25 infants we measured the tissue oxygenation index (TOI) of the liver and the brain continuously before, during and 30 minutes after feeding via a gastric tube. Simultaneously we measured arterial oxygen saturation (SaO2), heart rate (HR) and mean arterial blood pressure (MAP). In 10 other newborn infants we performed a test-retest analysis of the liver tissue oxygenation index to estimate the variability in repeated intra-individual measurements. The tissue oxygenation index of the liver increased significantly from 56.7 +/- 7.5% before to 60.3 +/- 5.6% after feeding (p < 0.005), and remained unchanged for the next 30 minutes. The tissue oxygenation index of the brain (62.1 +/- 9.7%), SaO2 (94.4 +/- 7.1%), heart rate (145 +/- 17.3 min-1) and mean arterial blood pressure (52.8 +/- 10.2 mm Hg) did not change significantly. The test-retest variability for intra-individual measurements was 2.7 +/- 2.1%. After bolus feeding the tissue oxygenation index of the liver increased as expected. This indicates that near infrared spectroscopy is suitable for monitoring changes in tissue oxygenation of the liver in newborn infants.

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OBJECTIVES: To assess the impact of neoadjuvant chemoradiotherapy (NCRT) on anastomotic leakage (AL) and other postoperative outcomes after esophageal cancer (EC) resection. BACKGROUND: Conflicting data have emerged from randomized studies regarding the impact of NCRT on AL. METHODS: Among 2944 consecutive patients operated on for EC between 2000 and 2010 in 30 European centers, patients treated by NCRT after surgery (n = 593) were compared with those treated by primary surgery (n = 1487). Multivariable analyses and propensity score matching were used to compensate for the differences in some baseline characteristics. RESULTS: Patients in the NCRT group were younger, with a higher prevalence of male sex, malnutrition, advanced tumor stage, squamous cell carcinoma, and surgery after 2005 when compared with the primary surgery group. Postoperative AL rates were 8.8% versus 10.6% (P = 0.220), and 90-day postoperative mortality and morbidity rates were 9.3% versus 7.2% (P = 0.110) and 33.4% versus 32.1% (P = 0.564), respectively. Pulmonary complication rates did not differ between groups (24.6% vs 22.5%; P = 0.291), whereas chylothorax (2.5% vs 1.2%; P = 0.020), cardiovascular complications (8.6% vs 0.1%; P = 0.037), and thromboembolic events (8.6% vs 6.0%; P = 0.037) were higher in the NCRT group. After propensity score matching, AL rates were 8.8% versus 11.3% (P = 0.228), with more chylothorax (2.5% vs 0.7%; P = 0.030) and trend toward more cardiovascular and thromboembolic events in the NCRT group (P = 0.069). Predictors of AL were high American Society of Anesthesiologists scores, supracarinal tumoral location, and cervical anastomosis, but not NCRT. CONCLUSIONS: Neoadjuvant chemoradiotherapy does not have an impact on the AL rate after EC resection (NCT 01927016).

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OBJECTIVE: To determine whether, during hemorrhagic shock, the effect of epinephrine on energy metabolism could be deleterious, by enhancing the oxygen requirement at a given level of oxygen delivery (DO2). DESIGN: Prospective, randomized, control trial. SETTING: Experimental laboratory. SUBJECTS: Two groups of seven mongrel dogs were studied. The epinephrine group received a continuous infusion of epinephrine (1 microgram/min/kg) while the control group received saline. INTERVENTION: Dogs were anesthetized with pentobarbital, and shock was produced by stepwise hemorrhage. MEASUREMENTS AND MAIN RESULTS: Oxygen consumption (VO2) was continuously measured by the gas exchange technique, while DO2 was independently calculated from cardiac output (measured by thermodilution) and blood oxygen content. A dual-lines regression fit was applied to the DO2 vs. VO2 plot. The intersection of the two regression lines defined the critical value of DO2. Values above critical DO2 belonged to phase 1, while phase 2 occurred below critical DO2. In the control group, VO2 was independent of DO2 during phase 1; VO2 was dependent on DO2 during phase 2. In the epinephrine group, the expected increase in VO2 (+19%) and DO2 (+50%) occurred under normovolemic conditions. During hemorrhage, VO2 immediately decreased, and the slope of phase 1 was significantly (p < .01) different from zero, and was significantly (p < .05) steeper than in the control group (0.025 +/- 0.005 vs. 0.005 +/- 0.010). However, the critical DO2 (8.7 +/- 1.7 vs. 9.7 +/- 2.4 mL/min/kg), the critical VO2 (5.6 +/- 0.5 vs. 5.5 +/- 0.9 mL/min/kg), and the slope of phase 2 (0.487 +/- 0.080 vs. 0.441 +/- 0.130) were not different from control values. CONCLUSIONS: The administration of pharmacologic doses of epinephrine significantly increased VO2 under normovolemic conditions due to the epinephrine-induced thermogenic effect. This effect progressively decreased during hemorrhage. The critical DO2 and the relationship between DO2 and VO2 in the supply-dependent phase of shock were unaffected by epinephrine infusion. These results suggest that during hemorrhagic shock, epinephrine administration did not exert a detrimental effect on the relationship between DO2 and VO2.

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In pancreatic beta-cells, the high Km glucose transporter GLUT2 catalyzes the first step in glucose-induced insulin secretion by glucose uptake. Expression of the transporter has been reported to be modulated by glucose either at the protein or mRNA levels. In this study we used the differentiated insulinoma cell line INS-1 which expresses high levels of GLUT2 and show that the expression of GLUT2 is regulated by glucose at the transcriptional level. By run-on transcription assays we showed that glucose induced GLUT2 gene transcription 3-4-fold in INS-1 cells which was paralleled by a 1.7-2.3-fold increase in cytoplasmic GLUT2 mRNA levels. To determine whether glucose regulatory sequences were present in the promoter region of GLUT2, we cloned and characterized a 1.4-kilobase region of mouse genomic DNA located 5' of the translation initiation site. By RNase protection assays and primer extension, we determined that multiple transcription initiation sites were present at positions -55, -64, and -115 from the first coding ATG and which were identified in liver, intestine, kidney, and beta-cells mRNAs. Plasmids were constructed with the mouse promoter region linked to the reporter gene chloramphenicol acetyltransferase (CAT), and transiently and stably transfected in the INS-1 cells. Glucose induced a concentration-dependent increase in CAT activity which reached a maximum of 3.6-fold at 20 mM glucose. Similar CAT constructs made of the human GLUT2 promoter region and the CAT gene displayed the same glucose-dependent increase in transcriptional activity when transfected into INS-1 cells. Comparison of the mouse and human promoter regions revealed sequence identity restricted to a few stretches of sequences which suggests that the glucose responsive element(s) may be conserved in these common sequences.