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Posterior neck pain following thyroidectomy is common because full neck extension is required during the procedure. We evaluated the effect of intra-operative transcutaneous electrical nerve stimulation on postoperative neck pain in patients undergoing total thyroidectomy under general anaesthesia. One hundred patients were randomly assigned to one of two groups; 50 patients received transcutaneous electrical nerve stimulation applied to the trapezius muscle and 50 patients acted as controls. Postoperative posterior neck pain and anterior wound pain were evaluated using an 11-point numerical rating scale at 30 min, 6 h, 24 h and 48 h following surgery. The numerical rating scale for posterior neck pain was significantly lower in the transcutaneous electrical nerve stimulation group compared with the control group at all time points (p < 0.05). There were no significant differences in the numerical rating scale for anterior wound pain at any time point. No adverse effects related to transcutaneous electrical nerve stimulation were observed. We conclude that intra-operative transcutaneous electrical nerve stimulation applied to the trapezius muscle reduced posterior neck pain following thyroidectomy. [ABSTRACT FROM AUTHOR]

Aim To evaluate the effect of reciprocating amplitude and progressive angular increment on fatigue life enhancement of NiTi rotary endodontic instruments. Methodology ProTaper F2 instruments were operated in steel artificial canals with both stationary reciprocating ( SR) and progressive reciprocating ( PR) motions. The SR motions involved symmetric to and fro reciprocation of ±180o, ±135o, ±90o, ±60o and ±45o. The PR motions were ±45o stationary motion superimposed with angular increments of 7o, 11o, 22.5o or 31o whenever an instrument completed 1, 10 or 30 reciprocating cycles (rc). The fatigue lives were compared with those under continuous rotation ( CR) and a reciprocating operation with a forward 144o and backward 72o motion proposed by Yared (2008). The statistical significance of these operating modes on fatigue life was examined using one way anova and post hoc Tukey's tests at P = 0.05. Fractographic analysis was also applied to probe the fracture mechanisms of different rotation motions. Results Fatigue life increased with decreasing reciprocating amplitude. Operating in the SR increased fatigue life by 355% over that in the CR. Except for the 22.5o increment, all PR motions yielded longer fatigue lives than the SR motion. A progressive reciprocating operation with a ± 45o reciprocating amplitude and a + 7o progressive angular increment every 10 reciprocating cycles (±45o/10rc/+7o) increased fatigue life by 990% over that in the CR motion. In terms of life enhancement over the CR motion, the larger the curvature the less are the differences between different movements. Single crack initiation sites were found in the CR and SR motions, while three crack initiation sites were typical in the ±45o/10rc/+7o motion. Conclusions Fatigue life increased with decreasing reciprocating amplitude in stationary reciprocation. A progressive reciprocating operation with ±45o/10rc/+7o motion led to significant fatigue life enhancement and multiple fatigue crack initiation in NiTi endodontic instruments. [ABSTRACT FROM AUTHOR]

This study investigated the effect of intrathecal fentanyl on the dose of propofol during sedation guided by Cerebral State Index monitoring. Seventy patients were randomly assigned to receive either fentanyl 25 μg ( n = 35) or normal saline ( n = 35) with hyperbaric bupivacaine 12.5 mg for spinal anaesthesia. Propofol was infused to maintain a Cerebral State Index value of 65–75 for 30 min. The propofol infusion time and dose required to reach a Cerebral State Index value of 75 were recorded together with the time required to reach a Cerebral State Index value higher than 90 after cessation of sedation. The onset time for sedation was faster and the recovery time was slower in the fentanyl group compared to those in the saline group (p = 0.018 and 0.027, respectively). The propofol doses required for onset and maintenance of sedation were significantly lower in the fentanyl group compared to those in the control group (p = 0.018 and < 0.001, respectively). In conclusion, adding intrathecal fentanyl 25 μg during spinal anaesthesia significantly reduced the dose of propofol required for sedation and prolonged the subsequent recovery time. [ABSTRACT FROM AUTHOR]

Prolongation of the corrected QT (QTc) interval is associated with various anaesthetic drugs. The QTc prolongation may become more exacerbated during laryngoscopy and intubation, which is possibly caused by sympathetic stimulation. The aim of this study was to investigate the effects of fentanyl on the QTc interval during propofol induction in healthy patients. The patients were randomly allocated to receive either fentanyl ( n = 25) or saline ( n = 25) before induction. The QTc interval was significantly prolonged immediately after intubation in control group compared to preceding values, but it did not change in the fentanyl group. The number of patients with the prolonged QTc interval exceeding 20 ms immediately after intubation compared to the baseline values was 14 in the control group and seven in the fentanyl group. In conclusion, pretreatment with fentanyl 2 μg.kg−1 significantly attenuated QTc prolongation associated with laryngoscopy and tracheal intubation during propofol induction. [ABSTRACT FROM AUTHOR]

Stimulation of the sympathetic nervous system associated with tracheal intubation causes corrected QT (QTc) interval prolongation. We postulated that the use of remifentanil during induction of anaesthesia might prevent this. Sixty unpremedicated, ASA grade 1 patients were selected and randomly allocated to receive either saline (group S), remifentanil 0.5 μg.kg−1 (group R 0.5) or remifentanil 1.0 μg.kg−1 (group R1.0) 1 min before laryngoscopy. The QTc interval was significantly prolonged immediately following intubation in group S and group R0.5, but it remained stable in group R1.0, compared with the QTc interval just before laryngoscopy. It is concluded that the administration of remifentanil 1.0 μg.kg−1 before intubation can prevent the prolongation of the QTc interval associated with tracheal intubation during induction of anaesthesia with sevoflurane. [ABSTRACT FROM AUTHOR]

Tensile and fatigue crack growth tests of 2205 duplex stainless steel (DSS) were performed in laboratory air, gaseous hydrogen at 0.2 MPa and saturated H2S solution. The longitudinal specimen showed a lesser degradation of tensile properties than the transverse ones in saturated H2S solution. The orientation of specimens with respect to rolling direction had little influence on the fatigue crack growth rate (FCGR) of the alloy in air. Furthermore, 2205 duplex stainless steel was susceptible to hydrogen-enhanced fatigue crack growth. Transmission electron micrographs, in addition to X-ray diffraction, revealed that the strain-induced austenite to martensite transformation occurred near the crack surface within a rather narrow depth. Fatigue fractography of the specimens tested in air showed mainly transgranular fatigue fracture with a small amount of flat facet fracture. Furthermore, extensive quasi-cleavage fracture of 2205 duplex stainless steel was associated with the hydrogen-enhanced crack growth. [ABSTRACT FROM AUTHOR]

The Laryngeal Tube® (LT), (VBM Medizintechnik, Sulz, Germany) is a relatively new supraglottic device for controlling the airway. Arterial carbon dioxide tension (PaCO2) can be estimated by monitoring the end-tidal tension of carbon dioxide (PETCO2). The relationship between PETCO2 and PaCO2 during controlled ventilation via the LT has not been reported. During general anesthesia, 45 patients were mechanically ventilated using an LT. PETCO2 and PaCO2 were measured once PETCO2 had reached a steady state. The LT was then removed and the trachea intubated using an endotracheal tube (ETT), and the identical ventilatory variables were resumed. Following stabilization, PETCO2 was again determined and PaCO2 estimated. The mean PETCO2 and PaCO2 values were 4.43 ± 0.26 kPa and 4.67 ± 0.32 kPa, respectively, during LT ventilation, and 4.36 ± 0.23 kPa and 4.61 ± 0.26 kPa, respectively, during ETT ventilation. Analysis of differences between the PETCO2 and PaCO2 values using the Bland and Altman method revealed a bias ± precision of 0.24 ± 0.15 kPa for LT and 0.27 ± 0.15 kPa for ETT. The root mean square error was 0.28 for the LT and 0.30 for the ETT. This study suggests that for healthy adult patients mechanically ventilated via the LT, the PETCO2 value reflects the PaCO2 value as closely as when patients are ETT ventilated, allowing capnometry to be used to evaluate the adequacy of ventilation. [ABSTRACT FROM AUTHOR]

Infiltration of foreign materials into a fatigue crack has previously been shown to be able to retard the crack and extend fatigue life. Most of the related studies were empirical and phenomenological in nature. To aid engineering decisions, it would be advantageous if the possible outcome of a repair can be evaluated beforehand. To this end, a crack closure model taking into account the additional closure effect of the infiltrant has been developed and verified against experimental results. With this model, the sensitivity of the repair effect to various parameters such as mechanical properties of the infiltrant, depth of penetration and infiltration load level can be assessed. [ABSTRACT FROM AUTHOR]

The safety and convenience of the tranvenous approach to long-term endocardial pacing are well established, but its principal draw-back is electrode displacement. The reported incidence of this complication varies between 3.0% to 36.7%, and is highest in the early post-implantation period before endocardial fixation of the electrode tip. Recently Brewser and Evans determined that the electrode displacement rate in 21 published series averaged 14.3%. However, the Inter Society Committee on Heart Disease (ICHD) report on pacemakers states that a rate or early displacement greater than 5% calls for a critical review of results. The training and expertise of the persons inserting the pacemaker electrodes undoubtedly are major factors which determine the proper transvenous placement of permanent cardiac electrodes. This paper deals with our clinical experience of 353 patients who received permanent transvenous pacemakers during the period September 1, 1974 through March 1, 1979, with emphasis on problems and complications encountered and overall results. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of single-dose intravenous dexamethasone on inflammatory responses, pain, nausea, and vomiting after uterine artery embolisation (UAE)., Design: Prospective, randomised, double-blind, and placebo-controlled study., Setting: Tertiary-care University centre in Korea., Population: Patients undergoing UAE for the treatment of symptomatic fibroids or adenomyosis., Methods: Patients were randomised to receive either intravenous dexamethasone (10 mg; dexamethasone group) or normal saline (control group) 1 hour before UAE. Both groups received fentanyl-based intravenous patient-controlled analgesia (PCA) during the 24 hours after UAE., Main Outcome Measures: The primary outcomes were the inflammatory and stress responses measured by white blood cell count, neutrophil percentage, C-reactive protein (CRP), interleukin-6 (IL-6), and cortisol. Secondary outcomes were severity of pain and incidence of nausea and vomiting., Results: Sixty-four patients were enrolled and 59 patients completed the study. CRP, IL-6, and cortisol were significantly lower in the dexamethasone group compared with the control group during the 24 hours after UAE. Although the cumulative dose of fentanyl and additional analgesics administered during the 24 hours after UAE were similar between the two groups, pain scores were significantly lower in the dexamethasone group from 12 hours after UAE, and the incidence of severe nausea and vomiting was lower in the dexamethasone group., Conclusions: The administration of single-dose intravenous dexamethasone as an adjunct to fentanyl-based intravenous PCA is effective in reducing inflammation and pain during the first 24 hours after UAE., Tweetable Abstract: Dexamethasone is effective in reducing inflammation and pain after uterine artery embolisation., (© 2015 Royal College of Obstetricians and Gynaecologists.)

Synthesis of recombinant protein (human mini-proinsulin) is investigated in fed-batch cultures at high cell concentration of recombinant Escherichia coli BL21(DE3)[pET-3aT2M2]. Transcription of the recombinant gene is controlled by a T7 promoter system. The human mini-proinsulin is characterized by a C-chain peptide consisting of only nine amino acids, whereas the C-chain peptide of natural human proinsulin is made up of 35 amino acids. It is expressed in a fusion protein with a small fusion partner (a peptide with 18 amino acids) and finally aggregated into insoluble inclusion bodies in cytoplasm of recombinant E. coli. The fermentative production of this small fusion mini-proinsulin may be of great advantage in enhancing the yield of human insulin. To find an optimum induction strategy, effects of various key cultivation variables on the mini-proinsulin production are examined in high cell density fed-batch cultures. No general correlation is found between preinduction specific growth rate and recombinant protein synthesis, which confers a flexibility in choosing the feeding strategy of preinduction media for achieving the high cell density cultures. A culture temperature below 37 degrees C is unfavorable for recombinant gene expression, and the T7-based expression system is almost completely repressed at 30 degrees C. The nutrient glucose and yeast extract concentration in postinduction feed media is optimized by applying a statistical method for medium optimization, i.e. response surface methodology, and an effective amount of inducer molecule (IPTG) is determined to maximize the specific recombinant protein formation. The mini-proinsulin production in E. coli culture is significantly influenced by the volumetric feed rate of postinduction media, which is shown to be closely related to the plasmid copy number in the recombinant cell. Consequently, in a single-stage fed-batch process, the mini-proinsulin concentration is increased up to 7 g/L, approximately 62 wt % of which corresponds to mature human insulin. A two-stage fed-batch fermentation process, with recombinant cell growth occurring at a constant growth rate and constant cell concentration in a growth fermenter and mini-proinsulin production in an induction fermenter, is designed, and its efficacy in increasing volumetric productivity of mini-proinsulin is demonstrated.