Stellate ganglion block does not change the tympanic membrane temperatures of either block or unblock sides in male volunteers

STUDY OBJECTIVES: To test the effect of stellate ganglion block on tympanic membrane temperatures. DESIGN: Prospective, observational study. SETTING: Department of Anesthesia, Yamanashi Medical University, Yamanashi, Japan. SUBJECTS: 7 healthy male volunteers. INTERVENTIONS: Stellate ganglion block, 6 ml of 1% mepivacaine hydrochloride, was administered. MEASUREMENTS AND MAIN RESULTS: Application of temperature probes (right and left tympanic membranes, eight adhesive right skin-surface temperatures at the chest, upper arm, digital fingertip, lateral calf, thigh, and great toe) was followed by a 30-minute control period. Temperatures were recorded every 15 minutes for 30 minutes before stellate ganglion block and every 5 minutes for 40 minutes after the block. The right tympanic membrane temperature increased slightly but not significantly compared with the left tympanic membrane temperature 10 minutes after stellate ganglion block and subsequently. Right skin-surface temperature gradients at the upper limb decreased slightly but not significantly after stellate ganglion block. Similarly, right skin-surface temperature gradients at the lower limb decreased slightly but not significantly after stellate ganglion block. CONCLUSIONS: Stellate ganglion block does not change the tympanic membrane temperatures of either block or unblock sides.     

Changes in capacitance and dielectric dissipation factor of water‐treed XLPE with applied voltage

The capacitance C and dielectric dissipation factor tan δ of a water‐treed XLPE sheet sample have been measured under the application of 100 V or 1 kV at 60 Hz. The values of C and tan δ at 1 kV are much larger than those at 100 V. The value of tan δ gradually decreases with the length of exposure to a voltage of 1 kV. On the other hand, C is almost constant versus the exposure time. The results have been discussed on the basis of a model in which filling of channels interconnecting voids by water is taken into account. It has been found that the increase of C and tan δ is caused by the growth of the water‐filled channel region on the application of voltage. The gradual decrease in tan δ with the exposure time is explained by the change in the conductivity of the water‐filled channel region, as a result of which the relaxation time shifts to higher frequencies. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(1): 12–20, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10160     

Autocatalytic processing of heme by lactoperoxidase produces the native protein-bound prosthetic group

The covalently bound prosthetic group of lactoperoxidase (LPO) has been obtained by hydrolysis of the protein and identified as a dihydroxylated heme. A baculovirus expression system has been developed for LPO and used to obtain protein in which the heme is only partially covalently bound. Reaction of the purified heme. apoLPO complex with H2O2 results in both autocatalytic modification of the heme and covalent attachment to the protein. Hydrolytic experiments establish that the autocatalytically incorporated heme is bound normally. Two monohydroxylated heme intermediates have been detected. The peroxidative activity of LPO increases in proportion to the extent of covalently bound heme. The LPO results provide a paradigm for autocatalytic incorporation of heme groups into the mammalian peroxidases, including myeloperoxidase and eosinophil peroxidase, all of which exhibit strong sequence similarity with LPO and have covalently-bound heme groups.     

Epidural anesthesia impairs both central and peripheral thermoregulatory control during general anesthesia

BACKGROUND: The authors tested the hypotheses that: (1) the vasoconstriction threshold during combined epidural/general anesthesia is less than that during general anesthesia alone; and (2) after vasoconstriction, core cooling rates during combined epidural/general anesthesia are greater than those during general anesthesia alone. Vasoconstriction thresholds and heat balance were evaluated under controlled circumstances in volunteers, whereas the clinical importance of intraoperative thermoregulatory vasoconstriction was evaluated in patients. METHODS: Five volunteers were each evaluated twice. On one of the randomly ordered days, epidural anesthesia (approximately T9 dermatomal level) was induced and maintained with 2-chloroprocaine. On both study days, general anesthesia was induced and maintained with isoflurane (0.7% end-tidal concentration), and core hypothermia was induced by surface cooling and continued for at least 1 h after fingertip vasoconstriction was observed. Patients undergoing colorectal surgery were randomly assigned to combined epidural/enflurane anesthesia (n = 13) or enflurane alone (n = 13). In appropriate patients, epidural anesthesia was maintained by an infusion of bupivacaine. The core temperature that triggered fingertip vasoconstriction identified the threshold. RESULTS: In the volunteers, the vasoconstriction threshold was 36.0 +/- 0.2 degrees C during isoflurane anesthesia alone, but significantly less, 35.1 +/- 0.7 degrees C, during combined epidural/isoflurane anesthesia. Cutaneous heat loss and the rates of core cooling were similar 30 min before vasoconstriction with and without epidural anesthesia. In the 30 min after vasoconstriction, heat loss decreased 33 +/- 13 W when the volunteers were given isoflurane alone, but only 8 +/- 16 W during combined epidural/isoflurane anesthesia. Similarly, the core cooling rates in the 30 min after vasoconstriction were significantly greater during combined epidural/isoflurane anesthesia (0.8 +/- 0.2 degrees C/h) than during isoflurane alone (0.2 +/- 0.1 degrees C/h). In the patients, end-tidal enflurane concentrations were slightly, but significantly, less in the patients given combined epidural/enflurane anesthesia (0.6 +/- 0.2% vs. 0.8 +/- 0.2%). Nonetheless, the vasoconstriction threshold was 34.5 +/- 0.6 degrees C in the epidural/enflurane group, which was significantly less than that in the other patients, 35.6 +/- 0.8 degrees C. When the study ended after 3 h of anesthesia, patients given combined epidural/enflurane anesthesia were 1.2 degrees C more hypothermic than those given general anesthesia alone. The rate of core cooling during the last hour of the study was 0.4 +/- 0.2 degrees C/h during combined epidural/enflurane anesthesia, but only 0.1 +/- 0.3 degrees C/h during enflurane alone. CONCLUSIONS: These data indicate that epidural anesthesia reduces the vasoconstriction threshold during general anesthesia. Furthermore, the markedly reduced rate of core cooling during general anesthesia alone illustrates the importance of leg vasoconstriction in maintaining core temperature.     

Immunosuppressive therapy with microemulsion cyclosporine A shortens the hospitalization of pediatric liver transplant recipients

Lipopolysaccharide (LPS) from S. typhimurium on exposure to gamma-radiation resulted in decrease in toxicity and was less mitogenic, Silver stained profiles of irradiated LPS on polyacrylamide gels revealed complete loss of its heteropolysaccharides which was confirmed further by analysing lipid A and LPS from Salmonella minnesota Re mutants on SDS-PAGE. Glucosamine and 2-keto 3-deoxy-octonate(Kdo) contents were significantly decreased on treatment. Lipid A obtained by removal of heteropolysaccharides from LPS was less toxic on exposure to gamma radiations.     

Trajectory control of robotic manipulators using neural networks

The authors present a nonlinear compensator using neural networks for trajectory control of robotic manipulators. The neural networks are not used to learn inverse-dynamics but to compensate nonlinearities of robotic manipulators. The performance of the proposed neural network controller is compared with that of the adaptive controller proposed by J.J. Craig (1988), and the effectiveness of the proposed neural network controller in compensating the unstructured uncertainties is clarified. A learning scheme using a model of known dynamics of manipulators is also proposed. The model learning can be done offline and needs no data recording of actual manipulator operation     

A near-infrared study of thermally induced structural changes in polyethylene crystal

Thermally induced structural changes of polyethylene (PE) have been studied by means of near-infrared (NIR) spectroscopy in the course of heating up to the melting temperature. NIR bands characteristic of the regular orthorhombic phase, the conformationally disordered hexagonal phase, and the amorphous phase have been successfully identified. It has been found that for the unoriented PE sample, the disordering process of orthorhombic lattice starts above room temperature and that it mostly occurs above 100 °C for the uniaxially oriented PE sample. In the latter case, the enhancement of crystallinity has clearly been detected just below T_m due to the reorganization of crystalline lattice. For the geometrically constrained ultradrawn PE sample, the phase transition from orthorhombic to hexagonal phase has been detected immediately below the melting point. The NIR bands characteristic of the hexagonal phase have been confirmed definitely. Usefulness of NIR spectroscopy has been demonstrated successfully in such a study of thermally induced phase transition behavior of PE samples with appreciable thickness, for which mid-IR spectroscopy is difficult to apply because of the intensity saturation of various key bands.     

Phosphorus removal under anoxic conditions in a continuous-flow A2N two-sludge process.

The Anaerobic-Anoxic/Nitrification (A2N) system is a continuous-flow, two-sludge process in which Poly-P bacteria are capable of taking up phosphate under anoxic conditions using nitrate as an electron acceptor. The process is very efficient because it maximizes the utilization of organic substrate for phosphorus and nitrogen removal. An experimental lab-scale A2N system fed with domestic sewage was tested over a period of 260 days. The purpose of the experiment was to examine phosphorus removal capacity of a modified A2N two-sludge system. Factors affecting phosphorus and nitrogen removal by the A2N system were investigated. These factors were the influent COD/TN ratio, Sludge Retention Time (SRT), Bypass Sludge Flow rate (BSF) and Return Sludge Flow rate (RSF). Results indicated that optimum conditions for phosphorus and nitrogen removal were the influent COD/TN ratio around 6.49, the SRT of 14 days, and the BSF and RSF were fixed at about 26-33% of influent flow rate.     

Primary structure of microbial transglutaminase from Streptoverticillium sp. strain s-8112

The complete amino acid sequence of transglutaminase (EC 2.3.2.13) (TGase), which is produced by a microorganism, Streptoverticillium sp. strain s-8112, and catalyzes the acyl transfer reaction between gamma-carboxyamide groups of glutamine residues in proteins and various primary amines, has been established by a combination of fast atom bombardment mass spectrometry and standard Edman degradation of peptide fragments produced by treatment of the TGase with various proteolytic enzymes and purified by a reversed-phase high performance liquid chromatography. The TGase consists of 331 amino acid residues with a chemical molecular weight of 37,863, in agreement with the observed molecular weight (37,869.2 +/- 8.8) determined from its electrospray ionization mass spectrum. The sequence of the enzyme is very different from those of mammalian TGases represented by guinea pig liver enzyme. The enzyme contains a sole Cys residue, which is essential for its catalytic activity. Hydropathy analysis indicated that the secondary structure of the region around the active site Cys residue is similar to those of mammalian TGases. These results suggest that this microbial protein evolved by a different pathway from that of mammalian TGases and acquired acyl transfer activity during the evolutional process.