bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myocardial Depressant Effects of Desflurane
Authors: Park Wyun Kon , Kim Myung Hee , Ahn Duck Sun , Chae Jee Eun , Jee Young Seok , Chung Namsik , Lynch Carl 
Published: April 2007

Background
The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods
The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mM K(+) Tyrode solution with 0.1 microm isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca(2+) release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na(+) Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca(2+) and K(+) currents of guinea pig ventricular myocytes were examined.

Results
Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mM K(+) Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na(+) Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca(2+) current and the delayed outward K(+) current but did not alter the inward rectifier K(+) current.

Conclusions
Myocardial depression by desflurane is due to decreased Ca(2+) influx, whereas depolarization-activated sarcoplasmic reticulum Ca(2+) release is modestly depressed, similar to the actions of isoflurane and sevoflurane. Desflurane depressed the delayed outward K(+) current associated with significant lengthening of cardiac action potentials.
Molecular Interaction of Droperidol with Human Ether-a-go-go -related Gene Channels
Authors: Schwoerer Alexander P. , Blütner Carmen , Brandt Sven , Binder Stephan , Siebrands Cornelia C. , Ehmke Heimo , Friederich Patrick 
Published: April 2007

Background
The cardiac safety of droperidol given at antiemetic doses is a matter of debate. Although droperidol potently inhibits human ether-a-go-go-related gene (HERG) channels, the molecular mode of this interaction is unknown. The role of amino acid residues typically mediating high-affinity block of HERG channels is unclear. It is furthermore unresolved whether droperidol at antiemetic concentrations induces action potential prolongation and arrhythmogenic early afterdepolarizations in cardiac myocytes.

Methods
Molecular mechanisms of HERG current inhibition by droperidol were established using two-electrode voltage clamp recordings of Xenopus laevis oocytes expressing wild-type and mutant channels. The mutants T623A, S624A, V625A, Y652A, and F656A were generated by site-directed mutagenesis. The effect of droperidol on action potentials was investigated in cardiac myocytes isolated from guinea pig hearts using the patch clamp technique.

Results
Droperidol inhibited currents through HERG wild-type channels with a concentration of half-maximal inhibition of 0.6-0.9 microM. Droperidol shifted the channel activation and the steady state inactivation toward negative potentials while channel deactivation was not affected. Current inhibition increased with membrane potential and with increasing duration of current activation. Inhibition of HERG channels was similarly reduced by all mutations. Droperidol at concentrations between 5 and 100 nM prolonged whereas concentrations greater than 300 nm shortened action potentials. Early afterdepolarizations were not observed.

Conclusions
Droperidol is a high-affinity blocker of HERG channels. Amino acid residues typically involved in high-affinity block mediate droperidol effects. Patch clamp results and computational modeling allow the hypothesis that interaction with calcium currents may explain why droperidol at antiemetic concentrations prolongs the action potential without inducing early afterdepolarizations.
Isoflurane Activates Sarcolemmal Adenosine Triphosphate-sensitive Potassium Channels in Vascular Smooth Muscle Cells
Authors: Tanaka Katsuya , Kawano Takashi , Nakamura Akiyo , Nazari Hossein , Kawahito Shinji , Oshita Shuzo , Takahashi Akira , Nakaya Yutaka 
Published: April 2007

Background
Recent evidence indicates that vascular adenosine triphosphate-sensitive potassium (K(ATP)) channels in vascular smooth muscle cells are critical in the regulation of vascular tonus under both physiologic and pathophysiologic conditions. Studies of the interaction of volatile anesthetics with vascular K(ATP) channels have been limited. In the current study, the authors investigated the molecular mechanism of isoflurane's action on vascular K(ATP) channels.

Methods
Electrophysiologic experiments were performed using cell-attached and inside-out patch clamp techniques to monitor native vascular K(ATP) channels, and recombinant K(ATP) channels comprised of inwardly rectifying potassium channel subunits (Kir6.1) and the sulfonylurea receptor (SUR2B). Isometric tension experiments were performed in rat thoracic aortic rings without endothelium.

Results
Application of isoflurane (0.5 mM) to the bath solution during cell-attached recordings induced a significant increase in K(ATP) channel activity, which was greatly reduced by pretreatment with a selective inhibitor of protein kinase A (PKA), Rp-cAMPS (100 microM). In inside-out patches, isoflurane did not activate K(ATP) channels. Isoflurane significantly activated wild-type recombinant SUR2B/Kir6.1 in cell-attached patches. Isoflurane-induced activation of wild-type channels was diminished in the PKA-insensitive mutant SUR2B-T633A/Kir6.1, SUR2B-S1465A/Kir6.1, and SUR2B/Kir6.1-S385A. In addition, the authors demonstrated that isoflurane-induced PKA activation was associated with isoflurane-induced decreases in isometric tension in the rat aorta.

Conclusion
These results indicate that isoflurane activates K(ATP) channels via PKA activation. PKA-dependent vasodilation induced by isoflurane also was observed in isometric tension experiments. Analysis of expressed vascular-type K(ATP) channels suggested that PKA-mediated phosphorylation of both Kir6.1 and SUR2B subunits plays a pivotal role in isoflurane-induced vascular K(ATP) channel activation.
A Prospective, Randomized Comparison between Ultrasound and Nerve Stimulation Guidance for Multiple Injection Axillary Brachial Plexus Block
Authors: Casati Andrea , Danelli Giorgio , Baciarello Marco , Corradi Maurizio , Leone Stefania , Di Cianni Simone , Fanelli Guido 
Published: April 2007

Background
This prospective, randomized, blinded study tested the hypothesis that ultrasound guidance can shorten the onset time of axillary brachial plexus block as compared with nerve stimulation guidance when using a multiple injection technique.

Methods
Sixty American Society of Anesthesiology physical status I-III patients receiving axillary brachial plexus block with 20 ml ropivacaine, 0.75%, using a multiple injection technique, were randomly allocated to receive either nerve stimulation (group NS, n = 30), or ultrasound guidance (group US, n = 30) for nerve location. A blinded observer recorded the onset of sensory and motor blocks, the need for general anesthesia (failed block) or greater than 100 microg fentanyl (insufficient block) to complete surgery, procedure-related pain, success rate, and patient satisfaction.

Results
The median (range) number of needle passes was 4 (3-8) in group US and 8 (5-13) in group NS (P = 0.002). The onset of sensory block was shorter in group US (14 +/- 6 min) than in group NS (18 +/- 6 min) (P = 0.01), whereas no differences were observed in onset of motor block (24 +/- 8 min in group US and 25 +/- 8 min in group NS; P = 0.33) and readiness to surgery (26 +/- 8 min in group US and 28 +/- 9 min in group NS; P = 0.48). No failed block was reported in either group. Insufficient block was observed in 1 patient (3%) of group US and 2 patients (6%) of group NS (P = 0.61). Procedure-related pain was reported in 6 patients (20%) of group US and 14 patients (48%) of group NS (P = 0.028); patient acceptance was similarly good in the two groups.

Conclusion
Multiple injection axillary block with ultrasound guidance provided similar success rates and comparable incidence of complication as compared with nerve stimulation guidance.
A Review of Neuraxial Epidural Morbidity
Authors: Cameron Christie M. , Scott David A. , McDonald Wendy M. , Davies Michael J. 
Published: April 2007

Background
The true incidence of serious neuraxial complications such as epidural hematoma or abscess after postoperative epidural infusions is still uncertain, in part due to inconsistencies in multicenter data collection.

Methods
Prospective data were collected over 16 yr from the authors' Acute Pain Service, which is based in a large tertiary teaching institution with a nonobstetric general surgical population.

Results
Over this period, 8,210 epidural catheters were inserted for postoperative analgesia and 32 computed tomography or magnetic resonance imaging scans were undertaken to exclude potential neuraxial complications. From these, two spinal hematomas (1:4,105) and six epidural abscesses (1:1,368) were diagnosed. Only one patient required surgical decompression. There were no long-term neurologic sequelae in any patient. In the past 6 yr, the frequency of investigation and diagnosis of epidural abscess has increased. Overall, the combined rate of epidural abscess or hematoma was 1:1,026, (0.1%; 95% confidence interval, 0.04-0.19%) with a need for operative intervention of 1:8,210 (0.01%; 95% confidence interval, 0.0-0.07%).

Conclusions
Spinal hematoma was very rare (< 0.05%). Epidural abscess was also rare (< 0.1%) but remains a potentially serious complication. Early diagnosis, using magnetic resonance imaging in patients with appropriate clinical indicators, before the onset of neurologic signs, enables conservative therapy in many cases and may help to prevent the development of serious neurologic sequelae.
Risk Factors for Chronic Pain after Hysterectomy
Authors: Brandsborg Birgitte , Nikolajsen Lone , Hansen Charlotte T. , Kehlet Henrik , Jensen Troels S. 
Published: April 2007

Background
Women scheduled to undergo hysterectomy for benign indications frequently have preoperative pelvic pain, but it is largely unknown why pain in some cases persists or even develops after surgery. This nationwide questionnaire and database study describes pain and identifies risk factors for chronic postsurgical pain 1 yr after hysterectomy for benign indications.

Methods
A pain questionnaire was mailed to 1,299 women 1 yr after hysterectomy. The response rate was 90.3%, and the presence of persistent pain was correlated to indication for surgery, surgical procedure, type of anesthesia, and other perioperative data.

Results
Pain was reported by 31.9% 1 yr after hysterectomy (chronic pain), and 13.7% had pain more than 2 days a week. Pain was not present before surgery in 14.9% of women with chronic postsurgical pain. Risk factors for chronic pain were preoperative pelvic pain (odds ratio [OR], 3.25; 95% confidence interval [CI], 2.40-4.41), previous cesarean delivery (OR, 1.54; CI, 1.06-2.26), pain as the main indication for surgery (OR, 2.98; CI, 1.54-5.77), and pain problems elsewhere (OR, 3.19; CI, 2.29-4.44). Vaginal hysterectomy versus total abdominal hysterectomy was not significantly associated with a lower risk of chronic pain (OR, 0.70; CI, 0.46-1.06). Importantly, spinal versus general anesthesia was associated with less chronic pain (OR, 0.42; CI, 0.21-0.85).

Conclusions
Thirty-two percent had chronic pain after hysterectomy, and risk factors were comparable to those seen in other operations. Interestingly, spinal anesthesia was associated with a lower frequency of chronic pain, justifying prospective study of spinal anesthesia for patients with a high risk for development of chronic postsurgical pain.
Constitutive Cyclooxygenase-2 Is Involved in Central Nociceptive Processes in Humans
Authors: Martin Frédéric , Fletcher Dominique , Chauvin Marcel , Bouhassira Didier 
Published: April 2007

Background
Prostaglandins play a major role in inflammation and pain. They are synthesized by the two cyclooxygenase (COX) isoforms: COX-1, which is expressed constitutively in many cell types, and COX-2, which is induced at the site of inflammation. However, unlike peripheral tissues, COX-2 is expressed constitutively in the central nervous system and may play a role in nociceptive processes. The current study aimed to investigate the role of constitutive COX-2 in the spinal transmission of nociceptive signals in humans.

Methods
The authors used 12 healthy volunteers to compare the effects of the specific COX-2 inhibitor sodium parecoxib (1 mg/kg) or placebo, administered intravenously in a double-blind and crossover fashion, on the electrophysiologic recordings of the nociceptive flexion (RIII) reflex. The RIII reflex is an objective psychophysiologic index of the spinal transmission of nociceptive signals and was recorded from the biceps femoris after electrical stimulation of the sural nerve. Two experiments, 7 days apart, were conducted in each volunteer. On each experimental day, the effects of parecoxib or placebo were tested on (1) the RIII reflex threshold, (2) the stimulus-response curves of the reflex up to the tolerance threshold (frequency of stimulation: 0.1 Hz), and (3) the progressive increase of the reflex and pain sensations (i.e., "windup" phenomenon) induced by a series of 15 stimulations at a frequency of 1 Hz (intensity 20% above RIII threshold).

Results
Parecoxib, but not placebo, significantly reduced the slope of the stimulus-response curve, suggesting a reduction in the gain of the spinal transmission of nociceptive signals. By contrast, the windup phenomenon was not significantly altered after administration of parecoxib or placebo.

Conclusions
This study shows that constitutive COX-2 modulates spinal nociceptive processes and that the antiinflammatory and antinociceptive actions of COX-2 inhibitors are not necessarily related.
Revisiting children ‘home on trial’ in the context of current concerns about the costs and effectiveness of the looked‐after children system: findings from an exploratory study
Authors: Broadhurst Karen , Pendleton Tamara 
Published: April 2007

ABSTRACTStatute and practice relating to s.31 part IV of The Children Act 1989 allow children subject to care orders to be placed at home with their parent(s). It is not uncommon for the courts to accept a plan for children to return home at the final hearing of care proceedings at which full care orders are granted. In such instances, children retain looked‐after status but, in terms of their day‐to‐day care, are looked after by parent(s). Whilst there are a small number of studies conducted in the 1990s relating to children ‘home on trial’, there is a much more limited recent literature. It is important to revisit this population of children, given current concerns about the burgeoning costs of child care proceedings and the looked‐after children system (LAC). This paper reports on a small‐scale exploratory study in one north‐west local authority area. Consisting of a file study and interviews with parents and professionals, the study examines the factors that contributed to initial removal of children to public care, the impact of the LAC system for children ‘home on trial’, stability of placements at home, as well as issues to do with the discharge of care orders. Particular attention is drawn to lone father headed households, a social group over‐represented in our sample. The study aims to inform further multi‐location studies.
Identification and characterization of microsatellite markers derived from expressed sequence tags of the sea cucumber Stichopus japonicus
Authors: CHEN LIMEI , LI QI 
Published: April 2007

AbstractEleven polymorphic microsatellite markers were identified in expressed sequence tags generated from Stichopus japonicus cDNA libraries. The numbers of alleles ranged from three to 10, and the expected and observed heterozygosities ranged from 0.378 to 0.870 and from 0.077 to 0.690, respectively. Significant deviations from Hardy–Weinberg expectations were observed at eight loci due to homozygote excess, suggesting the widespread occurrence of null alleles. The microsatellite markers will be useful for examining genetic population structure, parentage analysis and mapping studies of S. japonicus.
Microsatellites in the striped ground crickets, Allonemobius (Orthoptera: Gryllidae)
Authors: BIRGE LEANNA M. , BOGDANOWICZ STEVEN M. , HARRISON RICHARD G. , HOWARD DANIEL J. 
Published: April 2007

AbstractPolymorphic di‐, tri‐ and tetranucleotide repeats were examined in Allonemobius to determine whether they could serve as useful markers in studies of sperm precedence, population genetics and hybrid zone structure. Ten microsatellite DNA loci were sufficiently polymorphic to be used for paternity tests and showed no evidence of linkage disequilibrium or deviations from Hardy–Weinberg equilibrium in Allonemobius socius. Nine of 10 of these microsatellites can be amplified from three other Allonemobius species, suggesting that these markers will have widespread utility in this ground cricket genus.
Development of microsatellite markers in the noxious red tide‐causing dinoflagellate Heterocapsa circularisquama (Dinophyceae)
Authors: NAGAI S. , NISHITANI G. , YAMAGUCHI S. , YASUDA N. , LIAN C. L. , ITAKURA S. , YAMAGUCHI M. 
Published: April 2007

AbstractWe isolated 15 polymorphic microsatellites from one of the most noxious red tide‐causing dinoflagellate species, Heterocapsa circularisquama. These loci provide one class of highly variable genetic markers, as the number of alleles ranged from two to six, and the estimate of gene diversity from 0.205 to 0.684 across the 15 microsatellites. These loci have the potential to reveal genetic structure and gene flow among H. circularisquama populations.
A likely role for anoxygenic photosynthetic microbes in the formation of ancient stromatolites
Authors: BOSAK T. , GREENE S. E. , NEWMAN D. K. 
Published: April 2007

ABSTRACTAlthough cyanobacteria are the dominant primary producers in modern stromatolites and other microbialites, the oldest stromatolites pre‐date geochemical evidence for oxygenic photosynthesis and cyanobacteria in the rock record. As a step towards the development of laboratory models of stromatolite growth, we tested the potential of a metabolically ancient anoxygenic photosynthetic bacterium to build stromatolites. This organism, Rhodopseudomonas palustris, stimulates the precipitation of calcite in solutions already highly saturated with respect to calcium carbonate, and greatly facilitates the incorporation of carbonate grains into proto‐lamina (i.e. crusts). The appreciable stimulation of the growth of proto‐lamina by a nonfilamentous anoxygenic microbe suggests that similar microbes may have played a greater role in the formation of Archean stromatolites than previously assumed.
Niches of the pre‐photosynthetic biosphere and geologic preservation of Earth's earliest ecology
Authors: SLEEP NORMAN H. , BIRD DENNIS K. 
Published: April 2007

ABSTRACTThe tree of terrestrial life probably roots in non‐photosynthetic microbes. Chemoautotrophs were the first primary producers, and the globally dominant niches in terms of primary productivity were determined by availability of carbon dioxide and hydrogen for methanogenesis and sulfite reduction. Methanogen niches were most abundant where CO2‐rich ocean water flowed through serpentinite. Black smoker vents from basalt supplied comparable amount of H2. Hydrogen from arc volcanoes supported a significant methanogenic niche at the Earth's surface. SO2from arc volcanoes reacted with organic matter and hydrogen, providing a significant surface niche. Methane ascended to the upper atmosphere where photolysis produced C‐rich haze and CO, and H escaped into space. The CO and C‐rich haze supported secondary surface niches. None of these ecologies were bountiful; less than 1% of the CO2vented by ridge axes, arcs, and metamorphism became organic matter before it was buried in carbonate. In contrast, a photosynthetic biosphere leaves copious amounts of organic carbon, locally concentrated in sediments. Black shales are a classic geologic biosignature for photosynthesis that can survive subduction and high‐grade metamorphism.
Transforming an Eighteenth‐Century Archive into a Twenty‐First‐Century Database: The Early California Population Project
Authors: Hackel Steven W. , Reid Anne Marie 
Published: April 2007

AbstractThe Early California Population Project is a database recently completed by research scholars at the Henry E. Huntington Library. The project is part of a wave of new databases that are opening up various regions of Early America for additional study; yet, unlike other databases, the Early California Population Project's records are overwhelmingly of Indians. The database offers new opportunities for historians and anthropologists interested in Indians, Catholic missions, Spanish soldiers and settlers, and family and community formation along the Spanish colonial frontier of North America between 1769 and 1850.
EVALUATION OF GLOBAL YIELD, COMPOSITION, ANTIOXIDANT ACTIVITY AND COST OF MANUFACTURING OF EXTRACTS FROM LEMON VERBENA (ALOYSIA TRIPHYLLA[L'HÉRIT.] BRITTON) AND MANGO (MANGIFERA INDICA L.) LEAVES
Authors: PEREIRA CAMILA G. , MEIRELES M. ANGELA A. 
Published: April 2007

ABSTRACT In this work, the global yields, composition and antioxidant activity (AA) of extracts from lemon verbena (Aloysia triphylla) and mango (Mangifera indica) leaves obtained by different separation processes were determined. Lemon verbena extracts were obtained by supercritical fluid extraction (SFE), while mango leaf extracts were obtained by SFE, low‐pressure solvent extraction (LPSE) and hydrodistillation. The extract's constituents were analyzed by thin‐layer chromatography, gas chromatography/mass spectrometry and gas chromatography/flame ionization detector. The AA of the extracts was evaluated by the coupled reaction of β‐carotene/linolenic acid. The cost of manufacturing (COM) was estimated for the SFE extracts. Higher global yields were obtained using SFE at 350 bar/45C (1.49%) for lemon verbena and LPSE (3.04%) for mango. The AAs of the extracts were larger than that of the β‐carotene for both plants. The minimum values of COM were U.S.$26.96 and 52.45/kg of extract for lemon verbena and mango, respectively.
SUPERCRITICAL FLUID EXTRACTION AND DETERMINATION OF LUTEIN IN HETEROTROPHICALLY CULTIVATED CHLORELLA PYRENOIDOSA
Authors: WU ZHENGYUN , WU SHIMIN , SHI XIANMING 
Published: April 2007

ABSTRACTChlorella is a promising alternative resource of lutein, as it can be cultivated heterotrophically and efficiently in a fermentor. In this study, high density of Chlorella pyrenoidosa was achieved by fed‐batch cultivations. Lutein in Chlorella was extracted by supercritical fluid and was determined by high‐performance liquid chromatography and liquid chromatography‐mass spectrometry. The extraction degree of lutein reached 87.0% after 4‐h extraction under the optimized conditions of 50C, 25 MPa and modified CO2 with 50% ethanol. High purity of lutein could be obtained by supercritical fluid extraction with appropriate operation parameters. The whole process developed in this study may be useful for the commercial production of lutein.