Kazuaki Tange

Roles of Phosphatidylinositol 3-Kinase-Akt and NADPH Oxidase in Adenosine 5′-Triphosphate–Sensitive K+ Channel Function Impaired by High Glucose in the Human Artery

The present study was designed to examine roles of the phosphatidylinositol 3-kinase-Akt pathway and reduced nicotinamide-adenine dinucleotide phosphate oxidases in the reduced ATP-sensitive K+ channel function via superoxide produced by high glucose in the human artery. We evaluated the activity of the phosphatidylinositol 3-kinase-Akt pathway, as well as reduced nicotinamide-adenine dinucleotide phosphate oxidases, the intracellular levels of superoxide and ATP-sensitive K+ channel function in the human omental artery without endothelium. Levels of the p85-α subunit and reduced nicotinamide-adenine dinucleotide phosphate oxidase subunits, including p47phox, p22phox, and Rac-1, increased in the membrane fraction from arteries treated with d-glucose (20 mmol/L) accompanied by increased intracellular superoxide production. High glucose simultaneously augmented Akt phosphorylation at Ser 473, as well as Thr 308 in the human vascular smooth muscle cells. A phosphatidylinositol 3-kinase inhibitor LY294002, as well as tiron and apocynin, restored vasorelaxation and hyperpolarization in response to an ATP-sensitive K+ channel opener levcromakalim. Therefore, it can be concluded that the activation of the phosphatidylinositol 3-kinase-Akt pathway, in combination with the translocation of p47phox, p22phox, and Rac-1, contributes to the superoxide production induced by high glucose, resulting in the impairment of ATP-sensitive K+ channel function in the human visceral artery.

Tracheal intubation with the AirwayScope™ videolaryngoscope using straight vs curved reinforced tubes

To the Editor, The AirwayScope (AWS-S100; IMI Co., LTD., Koshigaya Saitama, Japan) is proposed as an alternative to the classical Macintosh laryngoscope for tracheal intubation in patients with cervical spine instability and/or neck stiffness, because it offers a better laryngeal view with less cervical spine movement. Its introducer, the INTLOCK, gives the straight reinforced tube a downward orientation, whereas the curved tube points upwards. Therefore, intubation difficulties may be more frequent with the straight tube because of more likely impingement with the arytenoids (Fig. 1). We compared straight and curved reinforced endotracheal tubes in terms of intubation success rate, delay of intubation, incidence of impingement with the arytenoids, and postoperative sore throat and hoarseness. After obtaining approval from the Research Ethics Committee of Wakayama Medical University and written informed patient consent, 55 patients (45–84 yr) American Society of Anesthesiologists’ physical status I–III undergoing lumbar spine surgery had their tracheal intubation performed with an AWS using a tube size 7.5 for females (F) and 8.0 for males (M). Patients were assigned to the curved group (curved reinforced tube; Covidien, Mansfield, MA, USA), n = 25, M/F = 14/11, or to the straight group (straight reinforced tube; Fuji Systems Co., Bunkyo-ku, Tokyo, Japan), n = 30, M/F = 14/16. If intubation did not succeed at the first attempt, another insertion was allowed by adjusting the AWS direction upward. Twenty-four hours after surgery, severity of sore throat and hoarseness were graded. Sample size calculation was performed using the time from laryngeal view to intubation as the primary end point. Twenty-five patients were needed for an 89% power to detect changes of 4.8 sec at a significance level of 0.05; standard deviation (SD) = 5.2. Statistical analysis was performed using the Mann–Whitney U test or the v test. Patients in both groups had similar characteristics, including sex ratio, age, body mass index, Mallampati score, and duration of anesthesia. The intubation success rate was greater in the curved group than in the straight group (100% vs 83.3%, respectively; P \ 0.05). When failure of tracheal intubation occurred in the straight group, it was due to the arytenoid cartilages interfering with the tube advancement and not due to an inadequate view of the larynx. The time from laryngeal view to intubation lasted longer in the straight group than in the curved group (11.1 ± 5.2 sec vs 6.3 ± 4.7 sec, respectively; mean ± SD; P \ 0.05), whereas the time until the glottic view did not differ between groups (10.2 ± 7.0 sec vs 9.8 ± 5.9 sec, respectively). These results suggest that intubation delay in the straight group was not due to the inadequate laryngeal view. The number of insertion attempts was greater in the straight group than in the curved group (2.4 ± 1.4 attempts vs 1.2 ± 0.5 attempts, respectively; P \ 0.05), reflecting the need for more upward adjustments of the introducer tip T. Minonishi, MD H. Kinoshita, MD, PhD (&) K. Tange, MD Y. Hatano, MD, PhD Wakayama Medical University, Wakayama, Japan e-mail: hkinoshi@nike.eonet.ne.jp; hkinoshi@wakayama-med.ac.jp

Reduction of adhesion formation by an angiotensin type 1 receptor antagonist

PurposeAdhesion formations are important causes of intestinal obstruction and can lead to infertility in women. The formation of adhesion appears to be determined by the fibrinolytic activity. Fibrinolysis itself is controlled by the plasminogen activator system, and several studies have shown that angiotensin type 1 (AT1) receptor antagonists can reduce plasminogen activator inhibitor-1 (PAI-1) expression, but the effect of AT1 receptor antagonists on PAI-1 expression involved in the adhesion formation remains unclear. The aim of this study was to investigate whether an AT1 antagonist, candesartan, can reduce PAI-1 mRNA expression using experimental model of peritoneal adhesions, which seems to reflect post-operative adhesions.MethodsUsing the experimental bowel adhesion rat model, we compared adhesion formation evaluated by the adhesion scoring system and PAI-1 mRNA expression.ResultsThe adhesion score and PAI-1 mRNA expression were significantly increased in the experimental bowel adhesion rat model. Candesartan administration decreased adhesion score and abolished increase in PAI-1 mRNA expression.ConclusionsThe AT1 receptor antagonist, candesartan, significantly decreased the severity of intraperitoneal adhesion, which was associated with an inhibition of PAI-1 mRNA expression in the mesenterium of rats. It suggests that AT1 receptor antagonists may be useful for the prevention of adhesion formation after surgery.

Benzoyl peroxide: a cause of skin injury in Japan?

for the treatment of acne in Japan, in cooperation with Nichiban Corporation (Tokyo, Japan). Also, we have found that none of these products containing benzoyl peroxide manufactured in Japan. We note that benzoyl peroxide is currently not approved by the Japanese government for medical use. However, it is still important to keep in mind, regarding this issue, that it is possible for people in Japan to personally import ointments or washes for acne that contain benzoyl peroxide [3].

Leakage from a nonelectric disposable pump.

cient welding inside the fl ow controller appeared to be the reason for this leakage. The fl ow controller is composed of multiple components that are assembled by welding, using ultrasonic waves. The manufacturing plant of Baxter Healthcare has acted to resolve this issue by the enhancement of their ultrasonic welding process using a new welding machine and improving their inspection procedures to detect leakage with a better detection device. We certainly appreciate this quick response from the company regarding this issue. This is the fi rst report to demonstrate the mechanism of leakage from the fl ow controller of a disposable nonelectric pump; however, the percent incidence of such leakage is unclear. We still need to be cautious about this phenomenon when disposable nonelectric pumps are used in clinical practice.

Low bispectral index values in a parturient with eclampsia undergoing caesarean delivery.

twice with 10 mL of 0.125% bupivacaine and fentanyl 2 lg/mL during labour, and the patient delivered a healthy infant three hours later. The following day, the mother reported left leg weakness. Clinical examination revealed isolated weakness of the left leg, with muscle power grade 4/5 in the distal muscle group. Sensory examination was normal. A diagnosis of transient nerve injury secondary to labour or the epidural was suspected, and daily follow-up arranged. The following day the patient developed new-onset paraesthesia in the left upper limb with worsening left lower limb weakness. Whilst awaiting specialist neurological opinion, the patient became more hypertensive, despite increasing doses of oral labetolol, and developed a more severe headache with emesis. Specialist neurological examination demonstrated global left sided motor weakness (power 3/5), with left sided hyperreflexia, hypertonia and an up-going plantar reflex. Urgent contrast MRI scan revealed a large (6.5 · 5 · 6 cm) cystic meningioma in the right parietal region and a second meningioma in front of the quadrigeminal plate, associated with marked cerebral oedema and significant midline shift (Fig. 1). The patient was transferred to the regional neurosurgical centre where she became acutely hypertensive and bradycardic and her Glasgow Coma Score decreased from 14/15 to 8/15. At emergency craniotomy the right parietal meningioma was removed and an extra ventricular drain inserted. Postoperatively the patient had residual left hemiparesis and visual loss. A second neurosurgical procedure was performed after five weeks to remove the quadrigeminal plate meningioma. Following prolonged rehabilitation, some improvement in left sided weakness occurred but unfortunately the visual loss remains. Diagnosis of brain tumours in pregnancy may be difficult as symptoms are often non-specific. In a study by Isla et al. of 126 413 pregnancies, seven women were found to have brain tumours, of which only two were meningiomas. Meningiomas may show accelerated growth during pregnancy due to the expression of pro-