bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of Signal Transduction Genes Differs after Hypoxic or Isoflurane Preconditioning of Rat Hippocampal Slice Cultures
Authors: Bickler Philip E. , Fahlman Christian S. 
Published: July 2009

Background
Preconditioning neurons with noninjurious hypoxia (hypoxic preconditioning, HPC) or the anesthetic isoflurane (APC) induces tolerance of severe ischemic stress. The mechanisms of both types of preconditioning in the hippocampus require moderate increases in intracellular Ca and activation of protein kinase signaling. The authors hypothesized that the expression of signal transduction genes would be similar after APC and HPC.

Methods
Hippocampal slice cultures prepared from 9-day-old rats were preconditioned with hypoxia (5 min of 95% nitrogen/5% carbon dioxide) or 1% isoflurane in air/5% carbon dioxide for 1 h. A day later, cultures were subjected to 10 min oxygen and glucose deprivation (simulated ischemia). Intracellular Ca, measured in CA1 neurons at the completion of preconditioning, and cell death in CA1, CA3, and dentate regions was assessed 48 h after simulated ischemia. Message RNA encoding 119 signal transduction genes was quantified with rat complimentary DNA microarrays from pre-oxygen-glucose deprivation samples.

Results
Both APC and HPC increased intracellular Ca approximately 50 nm and decreased CA1, CA3, and dentate neuron death by about 50% after simulated ischemia. Many signaling genes were increased after preconditioning, with hypoxia increasing more apoptosis/survival genes (8 of 10) than isoflurane (0 of 10). In contrast, isoflurane increased more cell cycle/development/growth genes than did hypoxia (8 of 14 genes, vs. 1 of 14).

Conclusions
Despite sharing similar upstream signaling and neuroprotective outcomes, the genomic response to APC and HPC is different. Increased expression of antiapoptosis genes after HPC and cell development genes after APC has implications both for neuroprotection and long-term effects of anesthetics.
Beneficial Effect of Propofol on Arterial Adenosine Triphosphate-sensitive K+Channel Function Impaired by Thromboxane
Authors: Haba Masanori , Kinoshita Hiroyuki , Matsuda Naoyuki , Azma Toshiharu , Hama-Tomioka Keiko , Hatakeyama Noboru , Yamazaki Mitsuaki , Hatano Yoshio 
Published: July 2009

Background
It is not known whether thromboxane A2 impairs adenosine triphosphate (ATP)-sensitive K channel function via increased production of superoxide in blood vessels and whether propofol as a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor restores this modification.

Methods
Rat aortas without endothelium were used for isometric force recording, measurements of membrane potential, and superoxide production and Western immunoblotting. Vasorelaxation to an ATP-sensitive K channel opener levcromakalim was obtained during contraction to phenylephrine (3 x 10(-7) M) or a thromboxane A2 analogue U46619 (3 x 10(-7) M). In some experiments, aortas were incubated with an ATP-sensitive K channel antagonist glibenclamide, a superoxide inhibitor Tiron, a nonselective NADPH oxidase inhibitor apocynin, a hydrogen peroxide scavenger catalase, a xanthine oxidase inhibitor allopurinol, a thromboxane receptor antagonist SQ29548 or propofol (3 x 10(-7) to 3 x 10(-6) M).

Results
Levcromakalim-induced vasorelaxation was abolished by glibenclamide in rings contracted with either vasoconstrictor agent. Tiron, apocynin, and propofol, but not catalase, augmented the vasodilator response as well as the hyperpolarization by levcromakalim in aortas contracted with U46619. Tiron, apocynin, SQ29548, and propofol, but not allopurinol, similarly reduced in situ levels of superoxide within aortic vascular smooth muscle exposed to U46619. Protein expression of a NADPH oxidase subunit p47phox increased in these arteries, and this augmentation was abolished by propofol.

Conclusions
Thromboxane receptor activation induces vascular oxidative stress via NADPH oxidase, resulting in the impairment of ATP-sensitive K channel function. Propofol reduces this stress via inhibition of a NADPH oxidase subunit p47phox and, therefore, restores ATP-sensitive K channel function.
Influence of Vancomycin on Renal Function in Critically Ill Patients after Cardiac Surgery
Authors: Hutschala Doris , Kinstner Christian , Skhirdladze Keso , Thalhammer Florian , Müller Markus , Tschernko Edda 
Published: July 2009

Background
Vancomycin is frequently used in clinical practice to treat severe wound and systemic infections caused by Gram-positive bacteria after cardiac surgery. The drug is excreted almost entirely by glomerular filtration and might exhibit nephrotoxic side effects. This study compared the nephrotoxic impact of vancomycin during continuous versus intermittent administration.

Methods
The authors analyzed 149 patients admitted to the intensive care unit during a 5-yr period. All patients were treated at the intensive care unit after elective open heart surgery. Thirty patients received a dosage of 1325 +/- 603 mg/d vancomycin (range 300-3400 mg/d) by intermittent infusion, and 119 patients received a mean dosage of 1935 +/- 688 mg/d (range 352-3411 mg/d) by continuous infusion.

Results
Nephrotoxicity occurred in 11 patients (36.7%) in the intermittent treatment group and in 33 patients (27.7%) in the continuous treatment group (P = 0.3; 95% CI = 0.283). Continuous veno-venous hemofiltration after vancomycin administration was required for 9 patients (9 of 30; 30%) in the intermittent treatment group and for 28 (28 of 119; 23.5%) in the continuous treatment group (P = 0.053; 95% CI = 0.256). A change of one unit (1 mg/l) in vancomycin serum concentration (DeltaVancoC) induced an average change of 0.04 mg/dl in creatinine (DeltaCrea) in the intermittent treatment group versus 0.006 mg/dl in the continuous treatment group (P < 0.001).

Conclusions
The data show that both the intermittent and also the continuous application modality of vancomycin are associated with deterioration of renal function in critically ill patients after cardiac surgery. However, continuous infusion showed the tendency to be less nephrotoxic than the intermittent infusion of vancomycin.
Oxygen Tissue Saturation Is Lower in Nonsurvivors than in Survivors after Early Resuscitation of Septic Shock
Authors: Leone Marc , Blidi Sami , Antonini François , Meyssignac Bertrand , Bordon Sébastien , Garcin Frédéric , Charvet Aude , Blasco Valéry , Albanèse Jacques , Martin Claude 
Published: July 2009

Background
Growing evidence suggests that the microvascular dysfunction is the key element of the pathogenesis of septic shock. This study's purpose was to explore whether the outcome of septic shock patients after early resuscitation using early goal-directed therapy is related to their muscle tissue oxygenation.

Methods
Tissue oxygen saturation (Sto2) was monitored in septic shock patients using a tissue spectrometer (InSpectra Model 325; Hutchinson Technology, Hutchinson, MN). For the purpose of this retrospective study, the Sto2 values were collected at the first measurement done after the macrohemodynamic variables (mean arterial pressure, urine output, central venous saturation in oxygen) were optimized.

Results
After the hemodynamic variables were corrected, no difference was observed between the nonsurvivors and survivors, with the exception of pulse oximetry saturation (94% [92-97%] vs. 97% [94-99%], P = 0.04). The Sto2 values were significantly lower in the nonsurvivors than in the survivors (73% [68-82%] vs. 84% [81-90%], P = 0.02). No correlations were found between the Sto2 and Spo2 (P = 0.7).

Conclusions
In septic shock patients, tissue oxygen saturation below 78% is associated with increased mortality at day 28. Further investigations are required to determine whether the correction of an impaired level of tissue oxygen saturation may improve the outcome of these patients.
Lumbar Sympathetic Blockade in Children with Complex Regional Pain Syndromes
Authors: Meier Petra M. , Zurakowski David , Berde Charles B. , Sethna Navil F. 
Published: July 2009

Background
Sympathetic blockade is used in the management of complex regional pain syndromes in children, but there are no data on the efficacy or mechanism(s) by which it produces pain relief. The purpose of this study is to compare the efficacy of lidocaine administered by lumbar sympathetic to IV route.

Methods
Under general anesthesia, children with unilateral lower limb complex regional pain syndromes received catheters along the lumbar sympathetic chain. In a double-blind placebo-controlled crossover design, patients received IV lidocaine and lumbar sympathetic saline or lumbar sympathetic lidocaine and IV saline. Spontaneous and evoked pain ratings and sensory thresholds were assessed before and after these two lidocaine/saline doses and between routes of lumbar sympathetic blockade and IV.

Results
Twenty-three patients, ages 10-18 yr, were enrolled. There was evidence for reduction of mean pain intensity of allodynia to brush (mean -1.4, 95% confidence interval [CI] -2.5 to -0.3) and to pinprick temporal summation (mean -1.3, 95% CI -2.5 to -0.2) with lidocaine treatment via the lumbar sympathetic blockade compared to IV route. Lumbar sympathetic blockade also produced significant reduction in pain intensity compared to pretreatment values of allodynia to brush, pinprick and pinprick temporal summation and verbal pain scores. IV lidocaine did not produce significant changes in spontaneous and evoked pain intensity measurements compared to pretreatment values. There were no carryover effects as assessed by route-by-period interaction.

Conclusions
Under the conditions of this study, the results provide some direct evidence that a component of pain may be mediated by abnormal sympathetic efferent activity.
Prognostic Value of Brain Natriuretic Peptide in Noncardiac Surgery
Authors: Ryding Alisdair D. S. , Kumar Saurabh , Worthington Angela M. , Burgess David 
Published: July 2009

Background
The prognostic role of brain natriuretic peptide (BNP) measurement before noncardiac surgery is unclear. The authors therefore performed a meta-analysis of studies in patients undergoing noncardiac surgery to assess the prognostic value of elevated BNP or N-terminal pro-BNP (NT-proBNP) levels in predicting mortality and major adverse cardiovascular events (MACE) (cardiac death or nonfatal myocardial infarction).

Methods
Unrestricted searches of MEDLINE and EMBASE bibliographic databases were performed using the terms "brain natriuretic peptide," "b-type natriuretic peptide," "BNP," "NT-proBNP," and "surgery." In addition, review articles, bibliographies, and abstracts of scientific meetings were manually searched. The meta-analysis included prospective studies that reported on the association of BNP or NT-proBNP and postoperative major adverse cardiovascular event (MACE) or mortality. The study endpoints were MACE, all-cause mortality, and cardiac mortality at short-term (less than 43 days after surgery) and longer-term (more than 6 months) follow-up. A random-effects model was used to pool study results; funnel-plot inspection was done to evaluate publication bias; Cochrane chi-square test and I testing was used to test for heterogeneity.

Results
Data from 15 publications (4,856 patients) were included in the analysis. Preoperative BNP elevation was associated with an increased risk of short-term MACE (OR 19.77; 95% confidence interval [CI] 13.18-29.65; P < 0.0001), all-cause mortality (OR 9.28; 95% CI 3.51-24.56; P < 0.0001), and cardiac death (OR 23.88; 95% CI 9.43-60.43; P < 0.00001). Results were consistent for both BNP and NT-proBNP. Preoperative BNP elevation was also associated with an increased risk of long-term MACE (OR 17.70; 95% CI 3.11-100.80; P < 0.0001) and all-cause mortality (OR 4.77; 95% CI 2.99-7.46; P < 0.00001).

Conclusions
Elevated BNP and NT-proBNP levels identify patients undergoing major noncardiac surgery at high risk of cardiac mortality, all-cause mortality, and MACE.
Desflurane Selectively Suppresses Long-latency Cortical Neuronal Response to Flash in the Rat
Authors: Hudetz Anthony G. , Vizuete Jeannette A. , Imas Olga A. 
Published: July 2009

Background
The effect of inhalational anesthetics on sensory-evoked unit activity in the cerebral cortex has been controversial. Desflurane has desirable properties for in vivo neurophysiologic studies, but its effect on cortical neuronal activity and neuronal responsiveness is not known. The authors studied the effect of desflurane on resting and visual evoked unit activity in rat visual cortex in vivo.

Methods
Desflurane was administered to adult albino rats at steady-state concentrations at 2%, 4%, 6%, and 8%. Flashes from a light emitting diode were delivered to the left eye at 5-s intervals. Extracellular unit activity within the right visual cortex was recorded using a 49-electrode array. Individual units were identified using principal components analysis.

Results
At 2% desflurane, 578 active units were found. Of these, 75% increased their firing rate in response to flash. Most responses contained early (0-100 ms) and late (150-1000 ms) components. With increasing desflurane concentration, the number of units active at baseline decreased (-13%), the number of early-responding units increased (+31%), and number of late-responding units decreased (-15%). Simultaneously, baseline firing rate decreased (-77%), the early response was unchanged, and the late response decreased (-60%).

Conclusions
The results indicate that visual cortex neurons remain responsive to flash stimulation under desflurane anesthesia, but the long-latency component of their response is attenuated in a concentration-dependent manner. Suppression of the long-latency response may be related to a loss of corticocortical feedback and loss of consciousness.
Moderate Exposure to Allogeneic Blood Products Is Not Associated with Reduced Long-term Survival after Surgery for Coronary Artery Disease
Authors: Weightman William M. , Gibbs Neville M. , Sheminant Matthew R. , Newman Mark A. J. , Grey Dianne E. 
Published: July 2009

Background
It has been suggested that blood transfusion has an adverse effect on long-term health, mainly through immune modulation and tumor promotion. To further assess this concern, the authors have performed a prospective observational study with the hypothesis that after taking perioperative risk factors relevant to long-term survival into account, patients undergoing coronary artery surgery who receive a perioperative allogeneic blood transfusion have worse long-term survival than those who do not.

Methods
The health outcomes of 1,841 consecutive subjects who had isolated nonemergency first-time coronary artery surgery and who survived more than 60 days after surgery were determined by record linkage. The association between length of survival, blood products transfused, and risk factors for long-term survival at entry to the study were determined by Cox proportional hazards regression.

Results
A total of 1,062 subjects were transfused. Of these, 266 subjects died during a mean follow-up of 8.1 yr. Of subjects who were transfused, 27% had a new malignant condition recorded on the death certificate, compared with 43% who were not transfused. Older age, cerebrovascular disease, use of a mammary graft, chronic pulmonary disease, renal dysfunction, reduced left ventricular function, and preoperative anemia were predictive of reduced long-term survival. There was no association between transfusion of blood products and long-term survival.

Conclusions
Patients who have undergone coronary artery surgery and who have received moderate amounts of blood as part of responsible and conservative management should be reassured that they are unlikely to experience a reduction in long-term survival.
Supraclavicular Approach Is an Easy and Safe Method of Subclavian Vein Catheterization Even in Mechanically Ventilated Patients
Authors: Czarnik Tomasz , Gawda Ryszard , Perkowski Tadeusz , Weron Rafal 
Published: July 2009

Background
Central venous catheters are commonly inserted for hemodynamic monitoring, volume monitoring, administration of medications, long-term total parenteral nutrition, access for renal replacement therapy, cardiopulmonary resuscitation, and difficult peripheral catheterization. The primary outcome of this study was to define venipuncture, catheterization and entire procedure success rates, and finally complication rate of subclavian venous catheterization via the supraclavicular approach with special focus on mechanically ventilated patients. The secondary outcome was to potentially make recommendations regarding this technique of central venous catheterization in mechanically ventilated patients.

Methods
The methodology of this prospective cohort study included subclavian venous catheterization via the supraclavicular approach. The technique of cannulation was the same for both the right and left sides, but the right claviculosternocleidomastoid angle was the preferred catheterization site. All procedures were performed by the first three authors, each of whom had different levels of experience. Each physician had performed at least 20 procedures before starting the study.

Results
In the majority of patients, venipuncture occurred during the first attempt. In 362 patients, catheterization attempts were performed, in whom 311 catheterizations (85.6%) were successful during the first attempt. The overall subclavian venous catheterization via supraclavicular approach procedure complication rate reached 1.7% (95% confidence interval 0.6-3.6%). The overall subclavian venous catheterization via the supraclavicular approach procedure success rate reached 88.9% (95% confidence interval 85.1-91.9%, n = 359).

Conclusions
Subclavian venous catheterization via the supraclavicular approach is an excellent method of central venous access in mechanically ventilated patients. The procedure success rate and the significant complication rate are comparable to other techniques of central venous catheterization.
General Anesthesia Increases Temporal Precision and Decreases Power of the Brainstem Auditory-evoked Response-related Segments of the Electroencephalogram
Authors: Scheller Bertram C. A. , Daunderer Michael , Pipa Gordon 
Published: July 2009

Background
Brainstem auditory-evoked responses (BAEP) have been reported to be unchanged in the presence of drugs used for induction and maintenance of general anesthesia. The aim of this study was to investigate if the signal segments after the auditory stimulus that are used to average the evoked response change under the influence of general anesthesia.

Methods
BAEPs of 156 patients scheduled for elective surgery under general anesthesia were investigated. Anesthetic regimen was randomized as a combination of one of four hypnotic drugs supplemented by one of four opioids. Signal segments after the auditory stimulus were obtained at six different periods of anesthesia. Power and phase properties of wavelet-filtered single-sweep auditory-evoked activity accounting for the waveform of the averaged BAEP wave V and the stability of amplitude and latency of the averaged BAEP wave V over periods were analyzed.

Results
Amplitude and latency of wave V change slightly with no significant difference between the periods. During anesthesia, however, the power of single sweeps is significantly reduced, whereas phase-locking properties of the according signal segments are significantly enhanced. This effect is independent of the anesthetic or opioid used.

Conclusions
General anesthesia affects phase and power of the segments of the electroencephalogram related to BAEP wave V. This study's results support the idea that temporally precise responses from a large number of neurons in the brainstem might play a crucial role in encoding and passing sensory information to higher subcortical and cortical areas of the brain.
Anesthesia for Cesarean Delivery and Learning Disabilities in a Population-based Birth Cohort
Authors: Sprung Juraj , Flick Randall P. , Wilder Robert T. , Katusic Slavica K. , Pike Tasha L. , Dingli Mariella , Gleich Stephen J. , Schroeder Darrell R. , Barbaresi William J. , Hanson Andrew C. , Warner David O. 
Published: July 2009

Background
Anesthetics administered to immature brains may cause histopathological changes and long-term behavioral abnormalities. The association between perinatal exposure to anesthetics during Cesarean delivery (CD) and development of learning disabilities (LD) was determined in a population-based birth cohort.

Methods
The educational and medical records of all children born to mothers residing in five townships of Olmsted County, Minnesota from 1976-1982 and remaining in the community at age 5 were reviewed to identify those with LDs. Cox proportional hazards regression was used to compare rates of LD between children delivered vaginally and via CD (with general or regional anesthesia).

Results
Of the 5,320 children in this cohort, 497 were delivered via CD (under general anesthesia n = 193, and regional anesthesia n = 304). The incidence of LD depended on mode of delivery (P = 0.050, adjusted for sex, birth weight, gestational age, exposure to anesthesia before age 4 yr, and maternal education). LD risk was similar in children delivered by vagina or CD with general anesthesia, but was reduced in children receiving CD with regional anesthesia (hazard ratio = 0.64, 95% confidence interval 0.44 to 0.92; P = 0.017 for comparison of CD under regional anesthesia compared to vaginal delivery).

Conclusion
Children exposed to general or regional anesthesia during CD are not more likely to develop LD compared to children delivered vaginally, suggesting that brief perinatal exposure to anesthetic drugs does not adversely affect long-term neurodevelopmental outcomes. The risk of LD may be lower in children delivered by CD whose mothers received regional anesthesia.
Depletion of Calcium Stores in Injured Sensory Neurons
Authors: Gemes Geza , Rigaud Marcel , Weyker Paul D. , Abram Stephen E. , Weihrauch Dorothee , Poroli Mark , Zoga Vasiliki , Hogan Quinn H. 
Published: July 2009

Background
Painful nerve injury leads to disrupted Ca signaling in primary sensory neurons, including decreased endoplasmic reticulum (ER) Ca storage. This study examines potential causes and functional consequences of Ca store limitation after injury.

Methods
Neurons were dissociated from axotomized fifth lumbar (L5) and the adjacent L4 dorsal root ganglia after L5 spinal nerve ligation that produced hyperalgesia, and they were compared to neurons from control animals. Intracellular Ca levels were measured with Fura-2 microfluorometry, and ER was labeled with probes or antibodies. Ultrastructural morphology was analyzed by electron microscopy of nondissociated dorsal root ganglia, and intracellular electrophysiological recordings were obtained from intact ganglia.

Results
Live neuron staining with BODIPY FL-X thapsigargin (Invitrogen, Carlsbad, CA) revealed a 40% decrease in sarco-endoplasmic reticulum Ca-ATPase binding in axotomized L5 neurons and a 34% decrease in L4 neurons. Immunocytochemical labeling for the ER Ca-binding protein calreticulin was unaffected by injury. Total length of ER profiles in electron micrographs was reduced by 53% in small axotomized L5 neurons, but it was increased in L4 neurons. Cisternal stacks of ER and aggregation of ribosomes occurred less frequently in axotomized neurons. Ca-induced Ca release, examined by microfluorometry with dantrolene, was eliminated in axotomized neurons. Pharmacologic blockade of Ca-induced Ca release with dantrolene produced hyperexcitability in control neurons, confirming its functional importance.

Conclusions
After axotomy, ER Ca stores are reduced by anatomic loss and possibly diminished sarco-endoplasmic reticulum Ca-ATPase. The resulting disruption of Ca-induced Ca release and protein synthesis may contribute to the generation of neuropathic pain.