Effects of ketamine on nicorandil induced ATP-sensitive potassium channel activity in cell line derived from rat aortic smooth muscle

Purpose : Nicorandil opens adenosine triphosphate-sensitive potassium (KATP) channels in the cardiovascular system and is being increasingly used for the treatment of angina pectoris. In the present study, we tested whether intravenous anesthetic agent ketamine affected nicorandil-induced native vascular KATP channel activation. Methods : We used excised inside-out patch clamp configurations to investigate the direct effects of ketamine racemate and S-(+)-ketamine on the activities of KATP channels in cultured rat aortic smooth muscle cells. Furthermore, we also investigated whether intracellular MgADP could modulate ketamine inhibition. Results : Nicorandil significantly activated KATP channel activity, whereas this channel activity was completely blocked by glibenclamide, a specific KATP channel blocker. Ketamine racemate inhibited the nicorandil induced KATP channel activity (IC50=34 1M, n=14), but S-(+)-ketamine was less potent than ketamine racemate in blocking nicorandil induced KATP channel activities (IC50=226 7M, n=10). Application of MgADP to the intracellular side of the channel was able to decrease the inhibitory potency of ketamine racemate on nicorandil induced KATP channel activities. Conclusions : Our results indicate that ketamine inhibits nicorandil induced KATP channel activities in a dose dependent and stereoselective manner. Furthermore, increase of intracellularMgADP attenuates the inhibitory potency of ketamine racemate

Imaging tools for mediastinal cystic lesions

Objective : To identify and differentiate patients with mediastinal cysts from those with cystic tumors requiring surgery. Methods : A total of 36 patients with mediastinal cystic lesions were enrolled. The patients were separated into two groups based on pathological findings : those with mediastinal cysts (n=23) and those with mediastinal tumors (n=13). The cystic components were measured using imaging parameters including mean computed tomography (CT) value, apparent diffusion coefficient (ADC), T1 signal intensity ratio (T1SI-ratio), and T2 signal intensity ratio (T2SI-ratio), acquired from magnetic resonance imaging (MRI) ; and standardized maximum uptake value (SUVmax) from 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Both groups were statistically compared. Results : Comparative parameters between the cysts and tumors revealed the following ratios : CT value, 40.9±21.2 versus (vs) 24.8±12.9 (p = 0.019) ; SUVmax, 1.18±0.50 vs 4.32±3.52 (p = 0.003) ; ADC, 3.46±0.96 vs 2.68±0.74 (p = 0.022) ; T1SI-ratio, 1.06±0.60 vs 1.35±0.92 (p = 0.648) ; T2SI-ratio, 5.40±1.80 vs 4.33±1.58 (p = 0.194). However, there was no correlation between FDG uptake and ADC value. Conclusions : SUVmax from 18F-FDG PET/CT and ADC derived from MRI were effective in facilitating preoperative diagnosis to differentiate mediastinal cysts from tumors. However, these examinations may be complementary to one another, not dominant

Effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery

AbstractBackgroundWe investigated the effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery.MethodsPatients were randomly divided into three groups: those maintained with sevoflurane (Group S, n=42), propofol (Group P, n=42), or combined propofol and sevoflurane (Group PS, n=42). We assessed complete response (no postoperative nausea and vomiting and no rescue antiemetic use), incidence of nausea and vomiting, nausea severity score, vomiting frequency, rescue antiemetic use, and postoperative pain at 2 and 24h after surgery.ResultsThe number of patients who exhibited a complete response was greater in Groups P and PS than in Group S at 0–2h (74%, 76% and 43%, respectively, p=0.001) and 0–24h (71%, 76% and 38%, respectively, p<0.0005). The incidence of nausea at 0–2h (Group S=57%, Group P=26% and Group PS=21%, p=0.001) and 0–24h (Group S=62%, Group P=29% and Group PS=21%, p<0.0005) was also significantly different among groups. However, there were no significant differences among groups in the incidence or frequency of vomiting or rescue antiemetic use at 0–24h.ConclusionCombined propofol and volatile anesthesia during laparoscopic gynecological surgery effectively decreases the incidence of postoperative nausea. We term this novel method of anesthesia “combined intravenous-volatile anesthesia (CIVA)”

Genetic analysis and phylogenetic characterization of pandemic (H1N1) 2009 influenza viruses that found in Nagasaki, Japan

SUMMARY: Isolation and determination of the nucleotide sequence of hemagglutinin (HA) of the pandemic (H1N1) 2009 influenza viruses found in Nagasaki, Japan, were conducted. The alignment results of the predicted HA amino acid sequences of these strains compared to the known global isolates revealed 5 specific amino acid differences located within the antigenic sites. The phylogenetic analyses revealed that the majority of the Nagasaki isolates could be classified into 6 phylogenetic clusters. Almost all isolates collected in the early season were classified into cluster I, which apparently originated from A/Nagasaki/HA-6/2009 isolated from a patient who returned from the Philippines. This cluster ceased to spread after November 2009. Between the end of August 2009 and January 2010, 5 new phylogenetic clusters (II-VI) emerged with viruses from different origins, and cluster III continuously advanced until March 2010. These results suggest that the onset of the influenza epidemic in Nagasaki originated from patient(s) who returned from the Philippines, and subsequently, various imported strains from different origins sustained the virus spread. Among the Nagasaki isolates, A/Nagasaki/HA-58/2009 having an H275Y mutation in the neuraminidase gene, which confers resistance to oseltamivir, was isolated. This is the first report in which an oseltamivir-resistant pandemic H275Y mutant was identified in Nagasaki Prefecture

Collagen Metabolism in Cutis Laxa Fibroblasts: Increased Collagenase Gene Expression Associated with Unaltered Expression of Type I and Type III Collagen

Collagen metabolism was studied in cutis laxa by analyzing collagen and collagenase gene expression in three dermal fibroblast strains from patients with congenital cutis laxa and comparing them with fibroblasts obtained from age-matched healthy subjects. Normal collagen synthetic activity was observed in the cutis laxa fibroblasts. An increased level of collagenase mRNA and unaltered levels of α1(I) and α1(III) collagen mRNA were found in all cutis laxa cell strains by dot blot hybridization. Reduced levels of elastin mRNA were also detected in these strains. However, no qualitative differences in these mRNA transcripts were detected between the control and cutis laxa fibroblasts by Northern blot analysis. Collagenase activity in fibroblast culture supernatants was then measured using fluorescein isothiocyanate (FITC)-labeled type I collagen. Increased collagenolytic activity in cutis laxa fibroblast culture supernatants was also found. These data suggest that increased collagenase expression of fibroblasts is related to the structural abnormality of dermal connective tissue in cutis laxa