Remifentanil versus fentanyl compared in a target-controlled infusion of propofol anesthesia: quality of anesthesia and recovery profile

Purpose  

The aim of the present study was to compare the clinical properties of fentanyl versus remifentanil in a target-controlled infusion (TCI) of propofol anesthesia regimen with bispectral index (BIS) monitoring.     

Effects of Subchronic Parathion Exposure on Cyclosporine Pharmacokinetics in Rats

Parathion undergoes enzymatic oxidation by hepatic cytochrome P-450 (CYP450) enzymes to the active metabolite paraoxon. Consequently, alterations in CYP450- dependent oxidation may affect the pharmacokinetics and pharmacodynamics of drugs that are metabolized in the liver. The CYP3A family is known to be responsible for the majority of cyclosporine metabolism. The aim of the present study was to assess the disposition kinetics of cyclosporine during subchronic parathion exposure. Male Wistar rats were administered either water or two different doses of parathion (1/100 LD50, 1/25 LD50; LD50 = 14 mg/kg) by gavage for 6 wk. Subsequently, rats in each experimental group received a single oral dose of cyclosporine (10 mg/kg), and serial blood samples were drawn from the carotid artery over a period of 48 h. Pharmacokinetic analysis showed that parathion increased the blood cyclosporine concentration twofold as evidenced by AUC (area under the curve), half life (t _½) and peak plasma concentration (C _max). This may be due to inhibition of cyclosporine metabolism, an interaction that may be of clinical relevance in immunosuppression therapy.     

Hyperbaric Oxygen Therapy Is as Effective as Dexamethasone in the Treatment of TNBS-E-Induced Experimental Colitis

Introduction Hyperbaric oxygen (HBO) has been demonstrated to be useful as an adjunctive therapy for Crohn’s disease. In the present study, HBO was tested as a treatment for trinitrobenzenesulfonic acid–ethanol (TNBS-E)-induced distal colitis, and its effects were compared with dexamethasone therapy. Methods A total of 48 Sprague-Dawley rats were separated into six groups: the control, and those treated with vehicle, TNBS-E, HBO, dexamethasone, or combined HBO + dexamethasone. The HBO treatment group was exposed to 100% HBO at 2 ATM for 75 min twice daily at 6-h intervals in a HBO chamber, both on the day of colitis induction and 3 days thereafter. Treatment with intraperitoneal dexamethasone twice daily was started 1 h before the induction of colitis and was continued for 7 days in the dexamethasone group. The rats were decapitated 8 days after the induction of colitis, and the colonic tissue wet weight, macroscopic and microscopic lesion score, and tissue myeloperoxidase (MPO) activity were determined. Results HBO therapy decreased the activity of experimental colitis measured by the tissue wet weight, macroscopic score, microscopic score, and MPO activity. The dexamethasone treatment significantly reduced the colitis activity as determined by the tissue MPO activity and wet weight. There were also decreases in the macroscopic and microscopic activity scores with the dexamethasone therapy; however, these changes were not statistically significant. The combined therapy with HBO and dexamethasone provided no additional benefit over HBO therapy alone. Conclusion HBO therapy can be a valuable therapeutic option in treatment of patients with inflammatory bowel disease. HBO therapy in the refractory patients deserves further, larger clinical studies.     

Two novel mutations in the sixth transmembrane segment of the thyrotropin receptor gene causing hyperfunctioning thyroid nodules.

Autonomously functioning thyroid nodules (AFTNs) can present as hyperfunctioning adenomas or toxic multinodular goiters. In the last decade, a large number of activating mutations have been identified in the thyrotropin receptor (TSHR) gene in autonomously functioning thyroid nodules. Most have been situated close to, or within the sixth transmembrane segment and third intracellular loop of the TSHR where the receptor interacts with the Gs protein. In this study we describe two novel mutations in the sixth transmembrane segment of the TSHR causing hyperfunctioning thyroid nodules. Genomic DNAs were isolated from four hyperfunctioning thyroid nodules, normal tissues and peripheral leukocytes of two patients with toxic multinodular goiter. After amplifying the related regions, TSHR and G(s)alpha genes were analyzed by single-strand conformation polymorphism (SSCP) analysis. The precise localization of the mutations was identified by automatic DNA sequence analysis. Functional studies were done by site-directed mutagenesis and transfection of a mutant construct into COS-7 cells. We identified two novel TSHR mutations in two hyperfunctioning thyroid nodules: Phe631Val in the first patient and Iso630Met in the second patient. Both mutant receptors display an increase in constitutive stimulation of basal cyclic adenosine monophosphate (cAMP) levels compared to the wild-type receptor. This confirms that these mutant receptors cause hyperfunctioning thyroid nodules.     

Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats

AIM： To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerati-ve colitis model. METHODS： Rats were randomly assigned to three groups： groupⅠ： control, group Ⅱ： experimental colitis, group Ⅲ： colitis plus melatonin treatment. On d 11 after colitis, plasma tumor necrosis factor-α, portal blood endotoxin levels, colon tissue myeloperoxidase and caspase-3 activity were measured. Bacterial translocation was quantified by blood, lymph node, liver and spleen culture. RESULTS： We observed a significantly reduced inciden-ce of bacterial translocation to the liver, spleen, mesen-teric lymph nodes, portal and systemic blood in animals treated with melatonin. Treatment with melatonin signifi-cantly decreased the caspase-3 activity in colonic tissues compared to that in trinitrobenzene sulphonic acid-trea-ted rats （16.11 ± 2.46 vs 32.97 ± 3.91, P 〈 0.01）. CONCLUSION： Melatonin has a protective effect on ba-cterial translocation and apoptosis.     

Hyperhomocysteinemia in inflammatory bowel disease patients without past intestinal resections: correlations with cobalamin, pyridoxine, folate concentrations, acute phase reactants, disease activity, and prior thromboembolic complications

OBJECTIVE: Homocysteine is a sulfur-containing amino acid formed during the demethylation of methionine and high levels of this amino acid is a known risk factor for both arterial and also venous thromboembolic complications. Deficiencies of cobalamin, folate, and pyridoxine may predispose subjects to hyperhomocysteinemia, a common phenomenon in inflammatory bowel disease (IBD) patients. The aim of this study was to identify the prevalence, risk factors of hyperhomocysteinemia and its correlation with prior thromboembolic events in an IBD cohort without past intestinal resections. METHODS: In this prospective study, we studied the concentrations of homocysteine, cobalamin, folate, and pyridoxine in 105 consecutive patients with IBD, of whom 11 had a prior history of thromboembolic complications. Data regarding smoking habits, medication use, disease location, and severity were gathered and patients with past intestinal resections were excluded. Age-matched and sex-matched 85 healthy volunteers served as controls and multivariate regression analysis was performed to find out independent predictors of hyperhomocysteinemia. RESULTS: The mean age (+/-SD) in the IBD cohort was 38.69+/-12.13 years, and 51% were male. The mean age in the control group was 37.61+/-10.05 years, and 52% were male. Homocysteine concentrations in patients were higher [16.35 micromol/L (range 6.82 to 48.15) vs. 9.60 micromol/L (range 4.97 to 17.39), P=0.000] and hyperhomocysteinemia had a higher prevalence in patients than in the controls (56.2% vs. 4.7%, chi2=56.179, P=0.000), thus IBD significantly increased the risk of hyperhomocysteinemia [odds ratio=25.973 (95% confidence interval: 8.861-76.128)]. Homocysteine concentrations in patients with a history of thrombosis were not higher than those without a history of thrombosis [16.29 micromol/L (range 8.45 to 34.75) vs. 16.36 micromol/L (range 6.82 to 48.15), not significant]. Hyperhomocysteinemia was found in 54.5% of patients with thrombosis and 56.4% of patients without thrombosis (not significant). On stepwise regression analysis, plasma cobalamin level, albumin concentration, erythrocyte sedimentation rate, and platelet count were found to be independent predictors of elevated homocysteine levels. CONCLUSIONS: IBD patients have a higher prevalence of hyperhomocysteinemia than do healthy controls and elevated homocysteine levels are independently associated with lower serum cobalamin, albumin levels and elevated erythrocyte sedimentation rate, and platelet count. There is no correlation between hyperhomocysteinemia and a history of prior thromboembolic events.     

Clinical Determinants of Incremental Shuttle Walk Test in Adults with Bronchiectasis

Introduction

Exercise capacity is impaired in patients with bronchiectasis. Incremental shuttle walk test (ISWT) stresses cardiorespiratory system physiologically to symptom-limited maximal exercise capacity. The purpose of this study was to investigate the clinical determinants of ISWT in adults with non-cystic fibrosis (CF) bronchiectasis.

Methods

Forty-one clinically stable bronchiectasis patients aged 18–72 years (27 females, 14 males) participated in the study. Subjects’ demographics and physical characteristics were recorded. Bronchiectasis Severity Index was used to identify disease severity. Pulmonary function test was performed. Dyspnea perception was assessed using the modified Medical Research Council Dyspnea Scale. Maximum inspiratory and expiratory pressures were measured. Peripheral muscle strength using a hand held dynamometer was measured. ISWT was performed to determine exercise capacity. Fatigue Severity Scale, Hospital Anxiety and Depression Scale, Leicester Cough Questionnaire were used to determine fatigue, psychosocial status, and quality of life.

Results

Patients’ mean ISWT distance was 469.5 m. The ISWT distance was significantly related with age (r?=???0.472), height (r?=?0.469), gender (r?=?0.520), FEV₁ (r?=?0.651), and FVC (r?=?0.545, p?<?0.05). Quadriceps muscle strength was higher in males (p?=?0.001) as compared to females. Age and gender were identified as independent predictors of the ISWT, explaining 42% of variance in ISWT distance (r?=?0.649, r²?=?0.421, F_(2,38)?=?13.794, p?<?0.001).

Conclusion

The clinical determinants of ISWT in clinically stable patients with non-CF bronchiectasis are age and gender. Pulmonary function, dyspnea perception, muscle strength, disease severity, fatigue, psychosocial factors, and health-related quality of life seems to have an independent effect on ISWT in this group of patients with bronchiectasis.