Extracorporeal Circulation Interference on Emergence from Anesthesia in Patients Submitted to Myocardial Revascularization

Background and objectives: Extracorporeal circulation (ECC) may change drug pharmacokinetics as well as brain function. The objectives of this study are to compare emergence time and postoperative sedation intensity assessed by the bispectral index (BIS) and the Ramsay sedation scale in patients undergoing myocardial revascularization (MR) with or without ECC. Method: Ten patients undergoing MR with ECC (ECC group) and 10 with no ECC (no-ECC group) were administered with sufentanyl, propofol 2.0 mu g.mL(-1) and pancuronium target controlled infusion. After surgery, propofol infusion was reduced to 1 mu g.mL(-1) and suspended when extubation was indicated. Patients BIS, Ramsay scale and time to wake up were assessed. Results: The ECC group showed lower BIS values beginning at 60 minutes after surgery (no-ECC = 66 +/- 13 and ECC = 53 +/- 14, p = 0.01) until 120 minutes after infusion (no-ECC = 85 +/- 8 and ECC = 73 +/- 12, p = 0.02). Sedation level measured by the Ramsay scale was higher in the ECC group at 30 minutes after the end of the surgery (no-ECC = 5 +/- 1 and ECC = 6 +/- 0, p = 0.021), at the end of infusion (no-ECC = 5 +/- 1 and ECC = 6 +/- 1, p = 0.012) and 5 minutes after the end of infusion (no-ECC = 4 +/- 1 and ECC = 5 +/- 0.42, p = 0.039). Emergence from anesthesia time was higher in the ECC group (no-ECC = 217 +/- 81 and ECC = 319 +/- 118, p = 0.038). Conclusions: There was a higher intensity of sedation after the end of surgery and a longer wake up time in ECC group, suggesting changes in the pharmacokinetics of propofol or effects of ECC on central nervous system.

Interferência da circulação extracorpórea no despertar da anestesia de pacientes submetidos à revascularização do miocárdio

JUSTIFICATIVA E OBJETIVOS: A circulação extracorpórea (CEC) pode alterar a farmacocinética dos fármacos, assim como a função cerebral. Os objetivos deste estudo foram comparar o tempo de despertar e a intensidade da sedação pós-operatória avaliada pelo índice bispectral (BIS) e pela escala de sedação de Ramsay, em pacientes submetidos à revascularização miocárdica (RM) com ou sem CEC. MÉTODO: Dez pacientes submetidos à RM com CEC (Grupo CEC) e 10 sem CEC (Grupo sem CEC) foram anestesiados com sufentanil, infusão alvo-controlada de propofol 2,0 µg.mL-1 e pancuronio. Após a cirurgia diminuiu-se a infusão de propofol para 1 µg.mL-1 que foi suspensa quando da indicação da extubação. Foram avaliados o BIS, a escala de Ramsay e o tempo de despertar dos pacientes. RESULTADOS: O grupo CEC apresentou valores menores de BIS desde 60 minutos após a cirurgia (sem CEC = 66 ± 13 e CEC = 53 ± 14, p = 0,01) até 120 minutos após a infusão (sem CEC = 85 ± 8 e CEC = 73 ± 12, p = 0,02). O nível de sedação pela escala de Ramsay foi maior no grupo CEC nos momentos 30 minutos após o final da cirurgia (sem CEC = 5 ± 1 e CEC = 6 ± 0, p = 0,021), no final da infusão (sem CEC = 5 ± 1 e CEC = 6 ± 1, p = 0,012) e 5 minutos após o final da infusão (sem CEC = 4 ± 1 e CEC = 5 ± 0,42, p = 0,039). O tempo de despertar foi maior no grupo CEC (sem CEC = 217 ± 81 e CEC = 319 ± 118, p = 0,038). CONCLUSÕES: Houve maior intensidade da sedação após o final da cirurgia e o maior tempo de despertar no grupo com CEC, sugerindo alteração na farmacocinética do propofol ou efeitos da CEC sobre o sistema nervoso central.

Macrofaunal succession in sediments around kelp and wood falls in the deep NE Pacific and community overlap with other reducing habitats

Sunken parcels of macroalgae and wood provide important oases of organic enrichment at the deep-sea floor, yet sediment community structure and succession around these habitat islands are poorly evaluated. We experimentally implanted 100-kg kelp falls and 200 kg wood falls at 1670 m depth in the Santa Cruz Basin to investigate (1) macrofaunal succession and (2) species overlap with nearby whale-fall and cold-seep communities over time scales of 0.25-5.5 yr. The abundance of infaunal macrobenthos was highly elevated after 0.25 and 0.5 yr near kelp parcels with decreased macrofaunal diversity and evenness within 0.5 m of the falls. Apparently opportunistic species (e.g., two new species of cumaceans) and sulfide tolerant microbial grazers (dorvilleid polychaetes) abounded after 0.25-0.5 yr. At wood falls, opportunistic cumaceans become abundant after 0.5 yr, but sulfide tolerant species only became abundant after 1.8-5.5 yr, in accordance with the much slower buildup of porewater sulfides at wood parcels compared with kelp falls. Species diversity decreased significantly over time in sediments adjacent to the wood parcels, most likely due to stress resulting from intense organic loading of nearby sediments (up to 20-30% organic carbon). Dorvilleid and ampharetid polychaetes were among the top-ranked fauna at wood parcels after 3.0-5.5 yr. Sediments around kelp and wood parcels provided low-intensity reducing conditions that sustain a limited chemoautrotrophically-based fauna. As a result, macrobenthic species overlap among kelp, wood, and other chemosynthetic habitats in the deep NE Pacific are primarily restricted to apparently sulfide tolerant species such as dorvilleid polychaetes, opportunistic cumaceans, and juvenile stages of chemosymbiont containing vesicomyid bivalves. We conclude that organically enriched sediments around wood falls may provide important habitat islands for the persistence and evolution of species dependent on organic- and sulfide-rich conditions at the deep-sea floor and contribute to beta and gamma diversity in deep-sea ecosystems. (C) 2010 Elsevier Ltd. All rights reserved.

Macrofaunal abundance and composition on the West Antarctic Peninsula continental shelf: Evidence for a sediment `food bank` and similarities to deep-sea habitats

To assess the impact and fate of the summer phytoplankton bloom on Antarctic benthos, we evaluated temporal and spatial patterns in macrofaunal abundance and taxonomic composition along a transect crossing the West Antarctic Peninsula (WAP) continental shelf As part of the FOODBANCS project, we sampled three sites at 550-625 m depths during five cruises occurring in November 1999, February-March 2000, June 2000, October 2000 and March 2001. We used a combination of megacore and box-core samplers to take 81 samples, and collected over 30,000 macrofaunal individuals, one of the largest sampling efforts on the Antarctic shelf to date. Comparison of the two sampling methodologies (box core and megacore) indicates similar macrofaunal densities, but with significant differences in taxonomic composition, a reflection of the different spatial scales of sampling. Macrorfaunal abundances on the WAP shelf were relatively high compared to other Antarctic shelf settings. At two of the three sampling sites, macrofaunal abundance remained constant throughout the year, which is consistent with the presence of a sediment `food bank`. Differences were observed in taxonomic composition at the site closest to the coast (Station A), driven by higher abundances of subsurface-deposit feeders. A significant temporal response was observed in the ampharetid polychaetes at Station A, with an abundance peak in the late fall post-bloom period; this may have resulted from juvenile recruitment during the summer bloom. Familial composition of macrofaunal polychaetes on the WAP shelf is more closely related to deep-sea abyssal fauna than to other shelf regions, and we hypothesize that this is a result of both local ecological conditions (low temperatures) and a reflection of historical processes such as extinctions on the Antarctic shelf during previous glacial maxima followed by recolonization from the deep sea. (C) 2008 Elsevier Ltd. All rights reserved.

The Oligocene-Neogene deep-sea Columbia Channel system in the South Brazilian Basin: Seismic stratigraphy and environmental changes

The Columbia Channel (CCS) system is a depositional system located in the South Brazilian Basin, south of the Vitoria-Trindade volcanic chain. It lies in a WNW-ESE direction on the continental rise and abyssal plain, at a depth of between 4200 and 5200 m. It is formed by two depocenters elongated respectively south and north of the channel that show different sediment patterns. The area is swept by a deep western boundary current formed by AABW. The system has been previously interpreted has a mixed turbidite-contourite system. More detailed study of seismic data permits a more precise definition of the modern channel morphology, the system stratigraphy as well as the sedimentary processes and control. The modern CCS presents active erosion and/or transport along the channel. The ancient Oligo-Neogene system overlies a ""upper Cretaceous-Paleogene"" sedimentary substratum (Unit U1) bounded at the top by a major erosive ""late Eocene-early Oligocene"" discordance (D2). This ancient system is subdivided into 2 seismic units (U2 and U3). The thick basal U2 unit constitutes the larger part of the system. It consists of three subunits bounded by unconformities: D3 (""Oligocene-Miocene boundary""), D4 (""late Miocene"") and D5 (""late Pliocene""). The subunits have a fairly tabular geometry in the shallow NW depocenter associated with predominant turbidite deposits. They present a mounded shape in the deep NE depocenter, and are interpreted as forming a contourite drift. South of the channel, the deposits are interpreted as a contourite sheet drift. The surficial U3 unit forms a thin carpet of deposits. The beginning of the channel occurs at the end of U1 and during the formation of D2. Its location seems to have been determined by active faults. The channel has been active throughout the late Oligocene and Neogene and its depth increased continuously as a consequence of erosion of the channel floor and deposit aggradation along its margins. Such a mixed turbidite-contourite system (or fan drift) is characterized by frequent, rapid lateral facies variations and by unconformities that cross the whole system and are associated with increased AABW circulation. (C) 2009 Elsevier B.V. All rights reserved.

Representation of the Weddell Sea deep water masses in the ocean component of the NCAR-CCSM model

We examine Weddell Sea deep water mass distributions with respect to the results from three different model runs using the oceanic component of the National Center for Atmospheric Research Community Climate System Model (NCAR-CCSM). One run is inter-annually forced by corrected NCAR/NCEP fluxes, while the other two are forced with the annual cycle obtained from the same climatology. One of the latter runs includes an interactive sea-ice model. Optimum Multiparameter analysis is applied to separate the deep water masses in the Greenwich Meridian section (into the Weddell Sea only) to measure the degree of realism obtained in the simulations. First, we describe the distribution of the simulated deep water masses using observed water type indices. Since the observed indices do not provide an acceptable representation of the Weddell Sea deep water masses as expected, they are specifically adjusted for each simulation. Differences among the water masses` representations in the three simulations are quantified through their root-mean-square differences. Results point out the need for better representation (and inclusion) of ice-related processes in order to improve the oceanic characteristics and variability of dense Southern Ocean water masses in the outputs of the NCAR-CCSM model, and probably in other ocean and climate models.

Deep chlorophyll maximum and upper ocean structure interactions: Case of the Guinea Thermal Dome

Deep Chlorophyll Maximum (DCM) modifies the upper ocean heat capture distribution and thus impacts water column temperature and stratification, as well as biogeochemical processes. This energetical role of the DCM is assessed using a 1 m-resolution 1D physical-biogeochemical model of the upper ocean, using climatological forcing conditions of the Guinea Dome (GD). This zone has been chosen among others because a strong and shallow DCM is present all year round. The results show that the DCM warms the seasonal thermocline by +2 degrees C in September/October and causes an increase of heat transfer from below into the mixed layer (ML) by vertical diffusion and entrainment, leading to a ML warming of about 0.3 degrees C in October. In the permanent thermocline, temperature decreases by up to 2 degrees C. The result is a stratification increase of the water column by 0.3 degrees C m(-1) which improves the thermocline realism when compared with observations. At the same time, the heating associated with the DCM is responsible for an increase of nitrate (+300%, 0.024 mu M), chlorophyll (+50%, 0.02 mu g l(-1)) and primary production (+45%: 10 mg C m(-2) day(-1)) in the ML during the entrainment period of October. The considered concentrations are small but this mechanism could be potentially important to give a better explanation of why there is a significant amount of nitrate in the ML. The mechanisms associated with the DCM presence, no matter which temperature or biogeochemical tracers are concerned, are likely to occur in a wide range of tropical or subpolar regions; in these zones a pronounced DCM is present at least episodically at shallow or moderate depths. These results can be generalized to other thermal dome regions where relatively similar physical and biogeochemical structures are encountered. After testing different vertical resolutions (10 m, 5 m, 2.5 m, 1 m and 0.5 m), we show that using at least a 1 to vertical resolution model is mandatory to assess the energetical importance of the DCM.

Biogeochemistry of a deep-sea whale fall: sulfate reduction, sulfide efflux and methanogenesis

Deep-sea whale falls create sulfidic habits Supporting chemoautotrophic communities, but microbial processes underlying the formation Of Such habitats remain poorly evaluated. Microbial degradation processes (sulfate reduction, methanogenesis) and biogeochemical gradients were studied in a whale-fall habitat created by a 30 t whale carcass deployed at 1675 m depth for 6 to 7 yr on the California margin. A variety of measurements were conducted including photomosaicking, microsensor measurements, radio-tracer incubations and geochemical analyses. Sediments were Studied at different distances (0 to 9 in) from the whale fall. Highest microbial activities and steepest vertical geochemical gradients were found within 0.5 m of the whale fall, revealing ex situ sulfate reduction and in vitro methanogenesis rates of up to 717 and 99 mmol m(-2) d(-1), respectively. In sediments containing whale biomass, methanogenesis was equivalent to 20 to 30%, of sulfate reduction. During in vitro sediment studies, sulfide and methane were produced within days to weeks after addition of whale biomass, indicating that chemosynthesis is promoted at early stages of the whale fall. Total sulfide production from sediments within 0.5 m of the whale fall was 2.1 +/- 3 and 1.5 +/- 2.1 mol d(-1) in Years 6 and 7, respectively, of which similar to 200 mmol d(-1) were available as free sulfide. Sulfate reduction in bones was much lower, accounting for a total availability of similar to 10 mmol sulfide d(-1). Over periods of at least 7 yr, whale falls can create sulfidic conditions similar to other chemosynthetic habitats Such as cold seeps and hydrothermal vents.

Molecular phylogeny and morphometric analyses reveal deep divergence between Amazonia and Atlantic Forest species of Dendrophryniscus

Dendrophryniscus is an early diverging clade of bufonids represented by few small-bodied species distributed in Amazonia and the Atlantic Forest. We used mitochondrial (414 bp of 12S, 575 bp of 16S genes) and nuclear DNA (785 bp of RAG-1) to investigate phylogenetic relationships and the timing of diversification within the genus. These molecular data were gathered from 23 specimens from 19 populations, including eight out of the 10 nominal species of the genus as well as Rhinella boulengeri. Analyses also included sequences of representatives of 18 other bufonid genera that were publically available. We also examined morphological characters to analyze differences within Dendrophryniscus. We found deep genetic divergence between an Amazonian and an Atlantic Forest clade, dating back to Eocene. Morphological data corroborate this distinction. We thus propose to assign the Amazonian species to a new genus, Amazonella. The species currently named R. boulengeri, which has been previously assigned to the genus Rhamphophryne, is shown to be closely related to Dendrophryniscus species. Our findings illustrate cryptic trends in bufonid morphological evolution, and point to a deep history of persistence and diversification within the Amazonian and Atlantic rainforests. We discuss our results in light of available paleoecological data and the biogeographic patterns observed in other similarly distributed groups. (C) 2011 Elsevier Inc. All rights reserved.

Transformer Operation at Deep Saturation: Model and Parameter Determination

This paper proposes a model that adequately describes the operation of the transformer at deep saturation, suitable for power-electronics applications, and a method for determining its parameters. Simulation and experimental results are presented to confirm the validity of the model and the method.

Verrucosispora maris sp nov., a novel deep-sea actinomycete isolated from a marine sediment which produces abyssomicins

Verrucosispora isolate AB-18-032(T), the abyssomicin- and proximicin-producing actinomycete, has chemotaxonomic and morphological properties consistent with its classification in the genus Verrucosispora. The organism formed a distinct phyletic line in the Verrucosispora 16S rRNA gene tree sharing similarities of 99.7%, 98.7% and 98.9% with Verrucosispora gifhornensis DSM 44337(T), Verrucosispora lutea YIM 013(T) and Verrucosispora sediminis MS 426(T), respectively. It was readily distinguished from the two latter species using a range of phenotypic features and from V. gifhornensis DSM 44337(T), its nearest phylogenetic neighbor, by a DNA G+C content of 65.5 mol% obtained by thermal denaturation and fluorometry and DNA:DNA relatedness values of 64.0% and 65.0% using renaturation and fluorometric methods, respectively. It is apparent from the combined genotypic and phenotypic data that strain AB-18-032(T) should be classified in the genus Verrucosispora as a new species. The name Verrucosispora maris sp. nov. is proposed for this taxon with isolate AB-18-032(T) (= DSM 45365(T) = NRRL B-24793(T)) as the type strain.

Diagnostic value of serum activin A and follistatin levels in women with peritoneal, ovarian and deep infiltrating endometriosis

Activin A is a growth factor, produced by the endometrium, whose actions are modulated by the binding protein follistatin. Both proteins are detectable in the peripheral serum and their concentrations may be increased in women with endometriosis. The present study was designed to evaluate whether serum levels of activin A and follistatin are altered, and therefore have a potential diagnostic value, in women with peritoneal, ovarian and deep infiltrating endometriosis. We performed a multicenter controlled study evaluating simultaneously serum activin A and follistatin concentrations in women with and without endometriosis. Women with endometriosis (n 139) were subdivided into three groups: peritoneal endometriosis (n 28); ovarian endometrioma (n 61) and deep infiltrating endometriosis (n 50). The control group (n 75) consisted of healthy women with regular menstrual cycles. Blood samples were collected from a peripheral vein and assayed for activin A and follistatin using commercially available enzyme immunoassay kits. The ovarian endometrioma group had serum activin A levels significantly higher than healthy controls (0.22 0.01 ng/ml versus 0.17 0.01 ng/ml, P 0.01). None of the endometriosis groups had serum follistatin levels which were significantly altered compared with healthy controls; however, levels found in the endometrioma group (2.34 0.32 ng/ml) were higher than that in the deep endometriosis group (1.50 0.17 ng/ml, P 0.05). The area under the receiver operating characteristic curve of activin A was 0.700 (95 confidence interval: 0.6050.794), while that of follistatin was 0.620 (95 confidence interval: 0.5100.730) for the diagnosis of ovarian endometrioma. The combination of both markers into a duo marker index did not improve significantly their diagnostic accuracy. The present study demonstrated that serum activin A and follistatin are not significantly altered in peritoneal or deep infiltrating endometriosis and have limited diagnostic accuracy in the diagnosis of ovarian endometrioma.

A study of effectiveness of midazolam sedation for prevention of myocardial arrhythmias in endosseous implant placement

Purpose: The study aimed to assess electrocardiographic alterations during oral implant placement surgeries under local anesthesia (lidocaine chlorhydrate with epinephrine), using 15 mg of midazolam as an anxiolytic premedication. Material and methods: The study randomly selected 20 patients, aged 21-50 years old, requiring bilateral mandibular dental implants. Each patient was assessed using placebo on one side and midazolam on the contralateral side, with random, double-blinded distribution. The electrocardiogram recorded 12 static leads every 2 min, while D2 derivations were recorded continuously. Results: No statistically significant differences were observed between the placebo and midazolam when analyzing the morphological behavior of the electrocardiographic wave and the presence of arrhythmias during the experiment. However, under sedation, assessment of the behavior of electrocardiographic parameters during different stages of the procedure revealed statistically significant differences (P<0.05) for heart rate, P-wave amplitude and duration of the RR and QTc intervals. The arrhythmias detected were considered low risk for patients without systemic alterations and were observed in 53.3% of patients. The most frequently occurring alterations were tachycardia, bradycardia, supraventricular and ventricular extrasystoles and blocked atrial extrasystole, which were similar for both placebo and midazolam, with the greatest incidence during the initial, incision and bone drilling stages. Conclusion: The use of 15 mg of midazolam made no difference compared with the placebo. The use of 15 mg of midazolam did not show an advantage in the incidence of arrhythmias The anxiolytic premedication does not prevent myocardial arrhythmias in endosseous implant placement. The clinical significance of the arrhythmias may not represent serious risks.

Near-Term Fetal Hypoxia-Ischemia in Rabbits MRI Can Predict Muscle Tone Abnormalities and Deep Brain Injury

Background and Purpose-The pattern of antenatal brain injury varies with gestational age at the time of insult. Deep brain nuclei are often injured at older gestational ages. Having previously shown postnatal hypertonia after preterm fetal rabbit hypoxia-ischemia, the objective of this study was to investigate the causal relationship between the dynamic regional pattern of brain injury on MRI and the evolution of muscle tone in the near-term rabbit fetus. Methods-Serial MRI was performed on New Zealand white rabbit fetuses to determine equipotency of fetal hypoxia-ischemia during uterine ischemia comparing 29 days gestation (E29, 92% gestation) with E22 and E25. E29 postnatal kits at 4, 24, and 72 hours after hypoxia-ischemia underwent T2- and diffusion-weighted imaging. Quantitative assessments of tone were made serially using a torque apparatus in addition to clinical assessments. Results-Based on the brain apparent diffusion coefficient, 32 minutes of uterine ischemia was selected for E29 fetuses. At E30, 58% of the survivors manifested hind limb hypotonia. By E32, 71% of the hypotonic kits developed dystonic hypertonia. Marked and persistent apparent diffusion coefficient reduction in the basal ganglia, thalamus, and brain stem was predictive of these motor deficits. Conclusions-MRI observation of deep brain injury 6 to 24 hours after near-term hypoxia-ischemia predicts dystonic hypertonia postnatally. Torque-displacement measurements indicate that motor deficits in rabbits progressed from initial hypotonia to hypertonia, similar to human cerebral palsy, but in a compressed timeframe. The presence of deep brain injury and quantitative shift from hypo-to hypertonia may identify patients at risk for developing cerebral palsy. (Stroke. 2012;43:2757-2763.)

Subthalamic deep brain stimulation modulates small fiber-dependent sensory thresholds in Parkinson's disease

The effects of deep brain stimulation of the subthalamic nucleus on nonmotor symptoms of Parkinson's disease (PD) rarely have been investigated. Among these, sensory disturbances, including chronic pain (CP), are frequent in these patients. The aim of this study was to evaluate the changes induced by deep brain stimulation in the perception of sensory stimuli, either noxious or innocuous, mediated by small or large nerve fibers. Sensory detection and pain thresholds were assessed in 25 PD patients all in the off-medication condition with the stimulator turned on or off (on- and off-stimulation conditions, respectively). The relationship between the changes induced by surgery on quantitative sensory testing, spontaneous CP, and motor abilities were studied. Quantitative sensory test results obtained in PD patients were compared with those of age-matched healthy subjects. Chronic pain was present in 72% of patients before vs 36% after surgery (P = .019). Compared with healthy subjects, PD patients had an increased sensitivity to innocuous thermal stimuli and mechanical pain, but a reduced sensitivity to innocuous mechanical stimuli. In addition, they had an increased pain rating when painful thermal stimuli were applied, particularly in the off-stimulation condition. In the on-stimulation condition, there was an increased sensitivity to innocuous thermal stimuli but a reduced sensitivity to mechanical or thermal pain. Pain provoked by thermal stimuli was reduced when the stimulator was turned on. Motor improvement positively correlated with changes in warm detection and heat pain thresholds. Subthalamic nucleus deep brain stimulation contributes to relieve pain associated with PD and specifically modulates small fiber-mediated sensations. (C) 2012 International Association for the Study of Pain. Published by Elsevier B. V. All rights reserved.