bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lansoprazole regimens that sustain intragastric pH >6.0: an evaluation of intermittent oral and continuous intravenous infusion dosages
Authors: METZ D. C. , AMER F. , HUNT B. , VAKILY M. , KUKULKA M. J. , SAMRA N. 
Published: March 2006

SummaryBackground  Orally and intravenously administered proton pump inhibitors have been shown to reduce rebleeding rates, surgery and transfusion requirement.Aim  To compare lansoprazole intravenous and orally disintegrating tablet (Prevacid SoluTab) regimens with a pantoprazole intravenously administered regimen in sustaining intragastric pH >6.0.Methods  Two similarly designed three‐way, randomized crossover studies each enrolled 36 Helicobacter pylori‐negative healthy volunteers. Study 1 regimens included intravenously administered bolus followed by 24‐h continuous infusion (lansoprazole 90 mg, 6 mg/h; lansoprazole 120 mg, 6 mg/h; pantoprazole 80 mg, 8 mg/h). Study 2 regimens included intravenous bolus followed by lansoprazole orally disintegrating tablet or intravenous continuous infusion for 24 h (lansoprazole 90 mg, lansoprazole orally disintegrating tablet 60 mg every 6 h; lansoprazole 120 mg, 9 mg/h; pantoprazole 80 mg, 8 mg/h). Percentage of time pH >6.0 was assessed with 24‐h intragastric pH monitoring.Results  All regimens produced comparable gastric acid suppression. In both studies, regimens superior to pantoprazole included lansoprazole 90 mg, 6‐mg/h; lansoprazole 90 mg, lansoprazole orally disintegrating tablet 60 mg q.d.s. and lansoprazole 120 mg, 9 mg/h (P ≤ 0.013). The lansoprazole 120‐mg, 6‐mg/h regimen (P = 0.082) was not superior to pantoprazole in percentage of time intragastric pH >6.0. Mild reaction at the intravenous injection site was the most frequently reported adverse event.Conclusions  The intravenous bolus and continuously infused lansoprazole or intravenous bolus and intermittent lansoprazole orally disintegrating tablet regimens are as effective as intravenous pantoprazole in sustaining intragastric pH >6.0.
Increased use of selective serotonin reuptake inhibitors in patients admitted with gastrointestinal haemorrhage: a multicentre retrospective analysis
Authors: WESSINGER S. , KAPLAN M. , CHOI L. , WILLIAMS M. , LAU C. , SHARP L. , CROWELL M. D. , KESHAVARZIAN A. , JONES M. P. 
Published: March 2006

SummaryBackground Selective serotonin reuptake inhibitors (SSRIs) can adversely affect platelet function and impair haemostasis. Various bleeding complications have been reported in persons taking SSRIs including an increased risk of gastrointestinal haemorrhage (GIH).Aim To evaluate SSRI use in patients hospitalized with GIH compared with controls.Methods A retrospective, multicentre case–control study determined use of SSRIs, non‐steroidal anti‐inflammatory drugs (NSAIDs), aspirin, clopidogrel, coumadin and enoxaparin in patients admitted with GIH and age‐ and sex‐matched controls. Exclusion criteria included liver disease, portal hypertension or bleeding diathesis.Results A total of 579 cases were matched with 1000 controls. SSRI use was 19.2% in cases and 13.6% in controls [OR (95% CI) = 1.5 (1.2–2.0); P = 0.003]. NSAIDs were used by 7.3% of cases and 3.8% of controls [OR = 2.0 (1.3–3.1); P = 0.003]. SSRI use was more strongly associated with lower [1.8 (1.2–2.8)] rather than upper [1.3 (0.83–1.9)] GIH. Significant interactions existed for SSRI use with NSAIDs and aspirin.Conclusions Patients admitted with GIH gastrointestinal bleeding were more likely to be taking SSRIs than controls. This association exists for lower as well as upper GIH. Physicians should be aware of this risk particularly in patients already using medications that increase GIH risk.
Comparison of the efficacy and safety of Eudragit‐L‐coated mesalazine tablets with ethylcellulose‐coated mesalazine tablets in patients with mild to moderately active ulcerative colitis
Authors: GIBSON P. R. , FIXA B. , PEKÁRKOVÁ B. , BÁTOVSKÝ M. , RADFORD‐SMITH G. , TIBITANZL J. , GABALEC L. , FLORIN T. H. J. , GREINWALD R. 
Published: March 2006

SummaryBackground  There are no comparative studies of coated mesalazine.Aim  To compare the efficacy and tolerability of Eudragit‐L‐ and ethylcellulose‐coated mesalazine tablets in patients with mild to moderately active ulcerative colitis.Methods  A double‐blind, double‐dummy, randomized parallel group trial was performed across 18 centres in Australia, and 20 in Eastern Europe. Patients were treated with 3 g mesalazine for 8 weeks with the primary efficacy end point being clinical remission.Results  Of 215 patients, 69% achieved clinical remission in both treatment groups (P < 0.001; chi‐square test) with no differences in frequency of adverse events. In the Australian cohort (n = 63), the Eudragit‐L group had a higher remission rate (73% vs. 36%) and responded 13 days faster, compared with those in the European group (67% vs. 84%, and 2 days respectively). No clear reasons for differences in treatment responses were identified.Conclusions  Eudragit‐L and ethylcellulose‐coated mesalazine tablets are well tolerated and equally effective in achieving remission in mild‐moderately active ulcerative colitis over 8 weeks.
Macro‐scale bird species richness patterns of the East Asian mainland and islands: energy, area and isolation
Authors: Ding Tzung‐Su , Yuan Hsiao‐Wei , Geng Shu , Koh Chao‐Nien , Lee Pei‐Fen 
Published: March 2006

AbstractAim  To create a map of bird species richness (BSR) in East Asia and to examine the effect of area, isolation, primary productivity, topographic heterogeneity, and human population density on BSR.Location  East Asia (from 70° E to 180° E longitude), including the eastern half of the Palaearctic Region, the entire Oriental Region, and the entire Wallacea Subregion.Methods  The breeding ranges of 2406 terrestrial bird species were mapped and overlaid to create a species richness map. The BSR map was transformed into a 100 × 100 km quadrat system, and BSR was analysed in relation to land area, average normalized difference vegetation index (NDVI), elevation range, and average population density.Results  In general, BSR declined from the Tropics to the Arctic. In mainland East Asia, however, BSR was highest around the Tropic of Cancer, and fluctuated between 30° and 50° N. Islands had lower BSR than adjacent mainland areas. The NDVI was strongly positively correlated with BSR in mainland areas and on islands. For mainland areas, NDVI explained 65% of the BSR variation, and topographic heterogeneity explained an additional 6% in ordinary least‐squares regression. On islands, NDVI explained 66% of BSR variation, island area explained 13%, and distance to mainland accounted for 1%.Main conclusions  In East Asia, we suggest that primary productivity is the key factor underpinning patterns of BSR. Primary productivity sets the upper limits of the capacity of habitats to support bird species. In isolated areas such as islands and peninsulas, however, BSR might not reach the richness limits set by primary productivity because the degree of isolation and area size also can affect species richness. Other factors, such as spatial heterogeneity, biotic interactions, and perturbations, may also affect species richness. However, their effects are secondary and are not as strong as primary productivity, isolation, and area size.
Administration of Kisspeptin‐54 into Discrete Regions of the Hypothalamus Potently Increases Plasma Luteinising Hormone and Testosterone in Male Adult Rats
Authors: Patterson M. , Murphy K. G. , Thompson E. L. , Patel S. , Ghatei M. A. , Bloom S. R. 
Published: March 2006

AbstractKisspeptin‐54 is the peptide product of the KiSS‐1 gene and an endogenous agonist of the GPR54 receptor. KiSS‐1 was initially discovered as a metastasis suppressor gene, but recent studies demonstrate that the kisspeptin/GPR54 system is a key regulator of the reproductive system. Disrupted GPR54 signalling causes hypogonadotrophic hypogonadism in rodents and man. Intracerebroventricular or peripheral administration of kisspeptin potently stimulates the hypothalamic‐pituitary‐gonadal (HPG) axis via the hypothalamic gonadotrophin‐releasing hormone system. We have investigated the effect of injection of kisspeptin‐54 into discrete hypothalamic regions on the HPG axis. To construct a dose–response curve for the effects of intrahypothalamic kisspeptin administration, adult male Wistar rats were cannulated into the medial preoptic area (MPOA) at the level of the organum vasculosum laminae terminalis (OVLT). Kisspeptin‐54 was injected into the MPOA at doses of 0.01, 0.1, 1, 10 and 100 pmol. At 60 min following injection of 1, 10 or 100 pmol kisspeptin‐54, plasma luteinising hormone (LH) and total testosterone levels were significantly increased. Adult male Wistar rats were then cannulated into the rostral preoptic area at the level of the OVLT (RPOA), the MPOA, the paraventricular (PVN), dorsomedial (DMN) and arcuate hypothalamic nuclei, and the lateral hypothalamic area. A dose of 1 pmol kisspeptin‐54 was administered into all areas. The circulating levels of LH and total testosterone were significantly increased 60 min postinjection of kisspeptin‐54 into the RPOA, MPOA, PVN and arcuate nucleus. Our results suggest that kisspeptin may mediate its effects on the HPG axis via these regions of the hypothalamus.
RNase Z in Escherichia coli plays a significant role in mRNA decay
Authors: Perwez Tariq , Kushner Sidney R. 
Published: March 2006

SummaryGenetic and biochemical analysis of RNase Z in eukaryotes, such as Arabadopsis thaliana, and prokaryotes like Bacillus subtilis have demonstrated that this endoribonuclease is essential for the maturation of tRNA precursors that do not contain a chromosomally encoded CCA determinant. As all Escherichia coli tRNA transcripts have chromosomally encoded CCA determinants, the function of its putative RNase Z homologue, the product of the elaC gene, is not clear. Here we demonstrate that the E. coli ElaC protein (RNase Z) endonucleolytically processes B. subtilis tRNA precursors lacking a CCA determinant both in vivo and in vitro. More importantly, E. coli RNase Z plays a significant role in mRNA decay, a previously unidentified activity for the enzyme. The purified RNase Z protein cleaves the rpsT mRNA at locations distinct from those obtained with RNase E. As expected, under physiological conditions E. coli and B. subtilis tRNA precursors containing a CCA determinant are not substrates. These results suggest a potentially important new role for the RNase Z family of proteins in RNA metabolism, particularly in organisms lacking RNase E.
Transport of nucleosides across the Plasmodium falciparum parasite plasma membrane has characteristics of PfENT1
Authors: Downie Megan J. , Saliba Kevin J. , Howitt Susan M. , Bröer Stefan , Kirk Kiaran 
Published: March 2006

SummaryLike all parasitic protozoa, the human malaria parasite Plasmodium falciparum lacks the enzymes required for de novo synthesis of purines and it is therefore reliant upon the salvage of these compounds from the external environment. P. falciparum equilibrative nucleoside transporter 1 (PfENT1) is a nucleoside transporter that has been localized to the plasma membrane of the intraerythrocytic form of the parasite. In this study we have characterized the transport of purine and pyrimidine nucleosides across the plasma membrane of ‘isolated’ trophozoite‐stage P. falciparum parasites and compared the transport characteristics of the parasite with those of PfENT1 expressed in Xenopus oocytes. The transport of nucleosides into the parasite: (i) was, in the case of adenosine, inosine and thymidine, very fast, equilibrating within a few seconds; (ii) was of low affinity [Km (adenosine) = 1.45 ± 0.25 mM; Km (thymidine) = 1.11 ± 0.09 mM]; and (iii) showed ‘cross‐competition’ for adenosine, inosine and thymidine, but not cytidine. The kinetic characteristics of nucleoside transport in intact parasites matched very closely those of PfENT1 expressed in Xenopus oocytes [Km (adenosine) = 1.86 ± 0.28 mM; Km (thymidine) = 1.33 ± 0.17 mM]. Furthermore, PfENT1 transported adenosine, inosine and thymidine, with a cross‐competition profile the same as that seen for isolated parasites. The data are consistent with PfENT1 serving as a major route for the uptake of nucleosides across the parasite plasma membrane.
On the effect of moisture bonding forces in air‐dry soils on threshold friction velocity of wind erosion
Authors: RAVI SUJITH , ZOBECK TED M. , OVER THOMAS M. , OKIN GREGORY S. , D'ODORICO PAOLO 
Published: March 2006

AbstractWind erosion is a dominant geomorphological process in arid and semi‐arid regions with major impacts on regional climate and desertification. The erosion process occurs when the wind speed exceeds a certain threshold value, which depends on a number of factors including surface soil moisture. The understanding and modelling of aeolian erosion requires a better understanding of the soil erodibility associated with different moisture conditions. In arid regions during the dry season, the atmospheric humidity plays an important role in determining the surface moisture content and the threshold shear velocity. By a series of wind tunnel tests and theoretical analyses, this dependence of threshold velocity on near surface air humidity is shown for three soils of different textures: sand, sandy loam, and clay loam. The results show that the threshold shear velocity decreases with increasing values of relative humidity for values of relative humidity between about 40% and 65%, while above and below this range the threshold shear velocity increases with air humidity. A theoretical framework is developed to explain these dependencies assuming an equilibrium between the surface soil moisture and the humidity of the overlying atmosphere. The conditions under which soil‐atmosphere equilibrium occurs were tested experimentally in the laboratory for different soils in order to determine the effect of grain surface area and texture on the time required to reach equilibrium starting from different initial conditions.
Microbial primary dolomite from a Norian carbonate platform: northern Calabria, southern Italy
Authors: MASTANDREA ADELAIDE , PERRI EDOARDO , RUSSO FRANCO , SPADAFORA ALESSANDRA , TUCKER MAURICE 
Published: March 2006

AbstractThe origin of fine‐grained dolomite in peritidal rocks has been the subject of much debate recently and evidence is presented here for a microbial origin of this dolomite type in the Norian Dolomia Principale of northern Calabria (southern Italy). Microbial carbonates there consist of stromatolites, thrombolites, and aphanitic dolomites. High‐relief thrombolites and stromatolites characterize sub‐tidal facies, and low‐relief and planar stromatolites, with local oncoids, typify the inter‐supratidal facies. Skeletal remains are very rare in the latter, whereas a relatively rich biota of skeletal cyanophycea, red algae and foraminifera is present in the sub‐tidal facies. Some 75% of the succession consists of fabric‐preserving dolomite, especially within the microbial facies, whereas the rest is composed of coarse dolomite with little fabric preservation. Three end‐members of dolomite replacement fabric are distinguished: type 1 and type 2, fabric retentive, with crystal size <5 and 5–60 μm, respectively; and type 3, fabric destructive, with larger crystals, from 60 to several hundred microns. In addition, there are dolomite cements, precipitated in the central parts of primary cavities during later diagenesis. Microbialite textures in stromatolites are generally composed of thin, dark micritic laminae of type 1 dolomite, alternating with thicker lighter‐coloured laminae of the coarser type 2 dolomite. Thrombolites are composed of dark, micritic clotted fabrics with peloids, composed of type 1 dolomite, surrounded by coarser type 2 dolomite. Marine fibrous cement crusts are also present, now composed of type 2 dolomite. Scanning electron microscope observations of the organic‐rich micritic laminae and clots of the inter‐supratidal microbialites reveal the presence of spherical structures which are interpreted as mineralized bacterial remains. These probably derived from the fossilization of micron‐sized coccoid bacteria and spheroidal–ovoidal nanometre‐scale dwarf‐type bacterial forms. Furthermore, there are traces of degraded organic matter, probably also of bacterial origin. The microbial dolomites were precipitated in a hypersaline environment, most likely through evaporative dolomitization, as suggested by the excess Ca in the dolomites, the small crystal size, and the positive δ18O values. The occurrence of fossilized bacteria and organic matter in the fabric‐preserving dolomite of the microbialites could indicate an involvement of bacteria and organic matter degradation in the precipitation of syn‐sedimentary dolomite.
Central venous catheter infections at a county hospital in Sweden: a prospective analysis of colonization, incidence of infection and risk factors
Authors: Hammarskjöld F. , Wallén G. , Malmvall B. E. 
Published: March 2006

Background:  Catheter‐related infection (CRI) is one of the most serious complications of the use of central venous catheters (CVCs), with an incidence of 2–30/1000 days in different studies. No major prospective study has evaluated the rate of CRI in Scandinavia. Since 1999, we have had a thorough programme for the insertion and care of all CVCs used at our hospital and its outpatient clinics. The purpose of this survey was to study the incidence of catheter tip colonization and CRI and their risk factors, and to compare these data with previous non‐Scandinavian studies.Methods:  We studied prospectively 605 CVCs in 456 patients in relation to insertion data, patient and catheter characteristics, catheterization time and microbiological cultures. Risk factors were analysed by multivariate analysis.Results:  Four hundred and ninety‐five (82%) of all CVCs were assessed completely. The total catheterization time was 9010 days. The incidence of positive tip culture was 7.66/1000 days, and the predominant microorganism was coagulase‐negative staphylococci. The incidence of CRI was 1.55/1000 days, and the only significant risk factor was the duration of catheterization with a relative risk of 1.009 per day [95% confidence interval (CI), 1.003–1.015]. Of the 14 cases with CRI, six were associated with candida species, and five of these were diagnosed in the intensive care unit.Conclusion:  In comparison with non‐Scandinavian studies, our practice of strict basic hygiene routines for CVC insertion and care is associated with a low incidence of CRI. However, there was a high proportion of candida species amongst these infections. The only risk factor for CRI was the duration of catheterization.
Pre‐oxygenation enhances induction with sevoflurane as assessed using bispectral index monitoring
Authors: Fassoulaki A. , Petropoulos G. , Kottis G. , Sarantopoulos C. 
Published: March 2006

Background:  Several methods may enhance the inhalational induction of anesthesia. In this randomized double‐blind study, we evaluated the speed of induction of anesthesia with sevoflurane with or without pre‐oxygenation.Methods:  Fifty‐four patients scheduled for hysteroscopy received for 10 min air or 100% oxygen via a facemask followed by ≥ 7% sevoflurane in 100% oxygen. During the first 300 s of sevoflurane administration, bispectral index (BIS) values were recorded every 30 s in all patients. In 14 patients, seven in each group, BIS, endtidal CO2, tidal volume, respiratory rate, SpO2, and heart rate were recorded every minute during the pre‐induction period and every 30 s during the first 5 min of sevoflurane administration.Results:  The BIS, endtidal CO2, tidal volume and respiratory rate did not differ between the oxygen or air breathing groups (P = 0.696, P = 0.999, P = 0.388, and P = 0.875, respectively), though the oxygen group exhibited lower tidal volumes by 16–20%. The SpO2 and heart rates were higher in the oxygen breathing group (P < 0.001 and P = 0.042, respectively). During sevoflurane administration, BIS values were lower in the oxygen group vs. the group breathing air, in particular at 90, 120, 150, 180 and 210 s (P = 0.001, P = 0.001, P = 0.001, P = 0.001 and P = 0.030, respectively). The endtidal CO2 and the tidal volumes between the groups did not differ. The two groups differed in the SpO2 and the heart rates during induction (P = 0.004 and 0.003, respectively).Conclusions:  Before sevoflurane administration, breathing 100% oxygen for 10 min enhances induction of anesthesia with sevoflurane.
Reliability of continuous cardiac output determination by pulse‐contour analysis in porcine septic shock
Authors: Schuerholz T. , Meyer M. Cobas , Friedrich L. , Przemeck M. , Sümpelmann R. , Marx G. 
Published: March 2006

Background:  Pulse‐contour analysis represents a technique for cardiac output (CO)‐measurement and allows continuously monitoring trends in CO. We evaluated reliability of pulse‐contour CO (COpc) in septic shock.Methods:  Seventeen anaesthetized and mechanically ventilated pigs were investigated. After baseline measurements, 14 animals received 0.75 g/kg body weight faeces into the abdominal cavity to induce sepsis and were observed over 9 h, three animals served as controls. A central venous catheter was inserted into the jugular vein and an arterial catheter for thermodilution was inserted into the femoral artery. Two bedside computers were used for COpc. After induction of sepsis, COpc‐computer No. 1 (COpcCAL) was recalibrated hourly. No further calibrations were performed in computer No. 2 (COpcNoCAL). We directly compared COpcCAL hourly before recalibration with COpcNoCAL. One hundred and seventy parallel triplicate determinations of CO were analysed using the method of Bland–Altman.Results:  Three hours after sepsis induction, correlation between recalibrated and non‐recalibrated CO was r = 0.74, P < 0.01, at 5 h r = 0.59, P < 0.05 and 9 h r = 0.02, NS. Three hours after sepsis induction, bias ± SD (limits of agreement) between both groups was 1.6 ± 15.5 (−29.4–32.6) ml/kg/min, at 5 h −15.0 ± 24.3 (−63.6–33.7) ml/kg/min and at 9 h −87.0 ± 90.8 (−268.5–94.6) ml/kg/min.Conclusion:  Continuous CO determination using pulse‐contour analysis is a reliable method of assessing CO up to 5 h without recalibration in porcine septic shock. Thus, COpc may be a useful tool for assessment of unpredictable haemodynamic changes in sepsis.
Volatile anesthetics evoke prolonged changes in the proteome of the left ventricule myocardium: defining a molecular basis of cardioprotection?
Authors: Kalenka A. , Maurer M. H. , Feldmann R. E. , Kuschinsky W. , Waschke K. F. 
Published: March 2006

Background:  Volatile anesthetics can alter cardiac gene and protein expression. Of those underlying molecular changes in gene and protein expression in the myocardium after exposure to volatile anesthetics that have been identified, some of them have been related to cardioprotection.Methods:  We used two‐dimensional gel electrophoresis and mass spectrometry to identify changes in the protein expression of the left ventricle myocardium of anesthesized rats. We maintained anesthesia for 3 h using isoflurane, sevoflurane or desflurane, respectively, at 1.0 minimum alveolar concentration (MAC) and dissected the left ventricular myocardium either immediately or 72 h after the end of anesthesia.Results:  We found changes of at least twofold in 106 proteins of the more than 1.600 protein spots discriminated in each gel. These differentially expressed proteins are associated with functions in glycolysis, mitochondrial respiration and stress response. No obvious difference could be observed between the patterns of differential expression of the three volatile anesthetics.Conclusion:  We provide the first study of post‐anesthetic protein expression profiles associated with three common volatile anesthetics. These volatile anesthetics promote a distinct change in the myocardial protein expression profile, whereby changes in the expression pattern still exist 72 h after anesthesia. These proteome changes are closely related to cardioprotection and ischemic preconditioning, indicating a common functional signaling of volatile anesthestics.