bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene expression patterns and catalytic properties of UDP-D-glucose 4-epimerases from barley (Hordeum vulgare L.)
Authors: Zhang Qisen , Hrmova Maria , Shirley Neil J. , Lahnstein Jelle , Fincher Geoffrey B. 
Published: March 2006

UGE (UDP-Glc 4-epimerase or UDP-Gal 4-epimerase; EC 5.1.3.2) catalyses the interconversion of UDP-Gal and UDP-Glc. Both nucleotide sugars act as activated sugar donors for the biosynthesis of cell wall polysaccharides such as cellulose, xyloglucans, (1,3;1,4)-β-D-glucan and pectins, together with other biologically significant compounds including glycoproteins and glycolipids. Three members of the HvUGE (barley UGE) gene family, designated HvUGE1, HvUGE2 and HvUGE3, have been characterized. Q-PCR (quantitative real-time PCR) showed that HvUGE1 mRNA was most abundant in leaf tips and mature roots, but its expression levels were relatively low in basal leaves and root tips. The HvUGE2 gene was transcribed at significant levels in all organs examined, while HvUGE3 mRNA levels were very low in all the organs. Heterologous expression of a near full-length cDNA confirmed that HvUGE1 encodes a functional UGE. A non-covalently bound NAD+ was released from the enzyme after denaturing with aqueous ethanol and was identified by its spectrophotometric properties and by electrospray ionization MS. The Km values were 40 μM for UDP-Gal and 55 μM for UDP-Glc. HvUGE also catalyses the interconversion of UDP-GalNAc and UDP-GlcNAc, although it is not known if this has any biological significance. A three-dimensional model of the HvUGE revealed that its overall structural fold is highly conserved compared with the human UGE and provides a structural rationale for its ability to bind UDP-GlcNAc.
Characterization of an Arabidopsis inositol 1,3,4,5,6-pentakisphosphate 2-kinase (AtIPK1)
Authors: Sweetman Dylan , Johnson Sue , Caddick Samuel E. K. , Hanke David E. , Brearley Charles A. 
Published: March 2006

The metabolic pathway(s) by which plants synthesize InsP6 (inositol 1,2,3,4,5,6-hexakisphosphate) remains largely undefined [Shears (1998) Biochim. Biophys. Acta 1436, 49–67], while the identities of the genes that encode enzymes catalysing individual steps in these pathways are, with the notable exception of myo-inositol phosphate synthase and ZmIpk [Shi, Wang, Wu, Hazebroek, Meeley and Ertl (2003) Plant Physiol. 131, 507–515], unidentified. A yeast enzyme, ScIPK1, catalyses the synthesis of InsP6 by 2-phosphorylation of Ins(1,3,4,5,6)P5 (inositol 1,3,4,5,6-pentakisphosphate). A human orthologue, HsIPK1, is able to substitute for yeast ScIPK1, restoring InsP6 production in a Saccharomyces cerevisiae mutant strain lacking the ScIPK1 open reading frame (ScIpk1Δ). We have identified an Arabidopsis genomic sequence, AtIPK1, encoding an Ins(1,3,4,5,6)P5 2-kinase. Inclusion of the AtIPK1 protein in alignments of amino acid sequences reveals that human and Arabidopis kinases are more similar to each other than to the S. cerevisiae enzyme, and further identifies an additional motif. Recombinant AtIPK1 protein expressed in Escherichia coli catalysed the synthesis of InsP6 from Ins(1,3,4,5,6)P5. The enzyme obeyed Michaelis–Menten kinetics with an apparent Vmax of 35 nmol·min−1·(mg of protein)−1 and a Km for Ins(1,3,4,5,6)P5 of 22 μM at 0.4 mM ATP. RT (reverse transcriptase)–PCR analysis of AtIPK1 transcripts revealed that AtIPK1 is expressed in siliques, leaves and cauline leaves. In situ hybridization experiments further revealed strong expression of AtIPK1 in male and female organs of flower buds. Expression of AtIPK1 protein in an ScIpk1Δ mutant strain restored InsP6 production and rescued the temperature-sensitive growth phenotype of the yeast.
Transcription of the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase type 3 gene, ATP2A3, is regulated by the calcineurin/NFAT pathway in endothelial cells
Authors: Hadri Lahouaria , Pavoine Catherine , Lipskaia Larissa , Yacoubi Sabrina , Lompré Anne-Marie 
Published: March 2006

Histamine, known to induce Ca2+ oscillations in endothelial cells, was used to alter Ca2+ cycling. Treatment of HUVEC (human umbilical-vein endothelial cell)-derived EA.hy926 cells with histamine for 1–3 days increased the levels of SERCA (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase) 3, but not of SERCA 2b, transcripts and proteins. Promoter-reporter gene assays demonstrated that this increase in expression was due to activation of SERCA 3 gene transcription. The effect of histamine was abolished by mepyramine, but not by cimetidine, indicating that the H1 receptor, but not the H2 receptor, was involved. The histamine-induced up-regulation of SERCA 3 was abolished by cyclosporin A and by VIVIT, a peptide that prevents calcineurin and NFAT (nuclear factor of activated T-cells) from interacting, indicating involvement of the calcineurin/NFAT pathway. Histamine also induced the nuclear translocation of NFAT. NFAT did not directly bind to the SERCA 3 promoter, but activated Ets-1 (E twenty-six-1), which drives the expression of the SERCA 3 gene. Finally, cells treated with histamine and loaded with fura 2 exhibited an improved capacity in eliminating high cytosolic Ca2+ concentrations, in accordance with an increase in activity of a low-affinity Ca2+-ATPase, like SERCA 3. Thus chronic treatment of endothelial cells with histamine up-regulates SERCA 3 transcription. The effect of histamine is mediated by the H1R (histamine 1 receptor) and involves activation of the calcineurin/NFAT pathway. By increasing the rate of Ca2+ sequestration, up-regulation of SERCA 3 counteracts the cytosolic increase in Ca2+ concentration.
AToxoplasma gondiiphosphoinositide phospholipase C (TgPI-PLC) with high affinity for phosphatidylinositol
Authors: Fang Jianmin , Marchesini Norma , Moreno Silvia N. J. 
Published: March 2006

The Toxoplasma gondii phosphoinositide-specific phospholipase C gene (TgPI-PLC) was cloned, sequenced and expressed in Escherichia coli and its enzymatic characteristics were investigated. TgPI-PLC is present in the genome as a single-copy gene consisting of 22 exons interrupted by 21 introns, and encodes a polypeptide of 1097 amino acids with a predicted molecular mass of 121 kDa. In addition to the conserved catalytic X and Y domains, TgPI-PLC contains an apparent N-terminal PH domain, an EF hand motif and a C-terminal C2 domain. When compared with mammalian δ-type PI-PLC, TgPI-PLC has an additional extended N-terminus and two insertions in the region between the X and Y domains, with a 31–35% identity over the whole sequence. Recombinant TgPI-PLC, as well as the native enzyme obtained from crude membrane extracts of the parasite, was more active with phosphatidylinositol than with phosphatidylinositol 4,5-bisphosphate as substrate. Indirect immunofluorescence analysis using an affinity-purified antibody against TgPI-PLC revealed that this enzyme localizes in the plasma membrane of the parasites.
Direct evidence for S-nitrosation of mitochondrial complex I
Authors: Burwell Lindsay S. , Nadtochiy Sergiy M. , Tompkins Andrew J. , Young Sara , Brookes Paul S. 
Published: March 2006

NO• (nitric oxide) is a pleiotropic signalling molecule, with many of its effects on cell function being elicited at the level of the mitochondrion. In addition to the well-characterized binding of NO• to the CuB/haem-a3 site in mitochondrial complex IV, it has been proposed by several laboratories that complex I can be inhibited by S-nitrosation of a cysteine. However, direct molecular evidence for this is lacking. In this investigation we have combined separation techniques for complex I (blue-native gel electrophoresis, Superose 6 column chromatography) with sensitive detection methods for S-nitrosothiols (chemiluminescence, biotin-switch assay), to show that the 75 kDa subunit of complex I is S-nitrosated in mitochondria treated with S-nitrosoglutathione (10 μM–1 mM). The stoichiometry of S-nitrosation was 7:1 (i.e. 7 mol of S-nitrosothiols per mol of complex I) and this resulted in significant inhibition of the complex. Furthermore, S-nitrosothiols were detected in mitochondria isolated from hearts subjected to ischaemic preconditioning. The implications of these results for the physiological regulation of respiration, for reactive oxygen species generation and for a potential role of S-nitrosation in cardioprotection are discussed.
Two exo-β-D-glucosaminidases/exochitosanases from actinomycetes define a new subfamily within family 2 of glycoside hydrolases
Authors: Côté Nathalie , Fleury Alain , Dumont-Blanchette Émilie , Fukamizo Tamo , Mitsutomi Masaru , Brzezinski Ryszard 
Published: March 2006

A GlcNase (exo-β-D-glucosaminidase) was purified from culture supernatant of Amycolatopsis orientalis subsp. orientalis grown in medium with chitosan. The enzyme hydrolysed the terminal GlcN (glucosamine) residues in oligomers of GlcN with transglycosylation observed at late reaction stages. 1H-NMR spectroscopy revealed that the enzyme is a retaining glycoside hydrolase. The GlcNase also behaved as an exochitosanase against high-molecular-mass chitosan with Km and kcat values of 0.16 mg/ml and 2832 min−1. On the basis of partial amino acid sequences, PCR primers were designed and used to amplify a DNA fragment which then allowed the cloning of the GlcNase gene (csxA) associated with an open reading frame of 1032 residues. The GlcNase has been classified as a member of glycoside hydrolase family 2 (GH2). Sequence alignments identified a group of CsxA-related protein sequences forming a distinct GH2 subfamily. Most of them have been annotated in databases as putative β-mannosidases. Among these, the SAV1223 protein from Streptomyces avermitilis has been purified following gene cloning and expression in a heterologous host and shown to be a GlcNase with no detectable β-mannosidase activity. In CsxA and all relatives, a serine-aspartate doublet replaces an asparagine residue and a glutamate residue, which were strictly conserved in previously studied GH2 members with β-galactosidase, β-glucuronidase or β-mannosidase activity and shown to be directly involved in various steps of the catalytic mechanism. Alignments of several other GH2 members allowed the identification of yet another putative subfamily, characterized by a novel, serine-glutamate doublet at these positions.
Electrohydrodynamic jetting of mouse neuronal cells
Authors: Eagles Peter A. M. , Qureshi Amer N. , Jayasinghe Suwan N. 
Published: March 2006

CAD (Cath.a-differentiated) cells, a mouse neuronal cell line, were subjected to electrohydrodynamic jetting at a field strength of 0.47–0.67 kV/mm, corresponding to an applied voltage of 7–10 kV. After jetting, the cells appeared normal and continued to divide at rates similar to those shown by control samples. Jetted cells, when placed in serum-free medium, underwent differentiation that was sustained for at least 1 month. Some of the droplets produced by jetting contained only a few cells. These results indicate that the process of jetting does not significantly perturb neuronal cells and that this novel approach might in the future be a useful way to deposit small numbers of living nerve cells on to surfaces.
Human Immunodeficiency Virus Knowledge and Attitudes Among Hospital-Based Healthcare Professionals in Guangxi Zhuang Autonomous Region, People's Republic of China
Authors: Anderson Allen F. , Qingsi Zheng , Guanglin Wu , Zhijun Li , Wei Liu 
Published: March 2006

AbstractBackground and Objective:Since the discovery of human immunodeficiency virus (HIV) on the Chinese mainland in 1985, the virus has spread to all provinces and autonomous regions. Although much research emphasis has been placed on studying behaviors and transmission knowledge among high-risk populations, especially drug abusers and commercial sex workers, little has been done to measure understanding within other risk groups. The objective of this study was to investigate HIV/acquired immunodeficiency syndrome (AIDS) knowledge and attitudes among hospital-based healthcare professionals in Guangxi Zhuang Autonomous Region in southern China.Methods:Data were gathered through a questionnaire completed by a convenience sample of individuals from three diverse hospitals.Results:Insufficient knowledge of the disease and its transmission resulted in more than 90% of the respondents expressing apprehension about contracting the virus and nearly 24% expressing reservations about caring for infected patients.Conclusion:Uncorrected, such attitudes and knowledge deficiencies have the potential to impact negatively on the quality of care, patient-practitioner safety, and proper postexposure prophylaxis.
Sharps-Related Injuries in California Healthcare Facilities: Pilot Study Results From the Sharps Injury Surveillance Registry
Authors: Gillen Marion , McNary Jennifer , Lewis Julieann , Davis Martha , Boyd Alisa , Schuller Mary , Curran Chris , Young Carol A. , Cone James 
Published: March 2006

AbstractBackground and Objectives:In 1998, the California Department of Health Services invited all healthcare facilities in California (n = 2,532) to participate in a statewide, voluntary sharps injury surveillance project The objectives were to determine whether a low-cost sharps registry could be established and maintained, and to evaluate the circumstances surrounding sharps injuries in California.Results:Approximately 450 facilities responded and reported a total of 1,940 sharps-related injuries from January 1998 through January 2000. Injuries occurred in a variety of healthcare workers (80 different job titles). Nurses sustained the highest number of injuries (n = 658). In hospital settings (n = 1,780), approximately 20% of the injuries were associated with drawing venous blood, injections, or assisting with a procedure such as suturing. As expected, injuries were caused by tasks conventionally related to specific job classifications. The overall results approximate those reported by the Centers for Disease Control and Prevention's National Surveillance System for Health Care Workers and the University of Virginia's Exposure Prevention Information Network.Conclusion:These data further support findings from previous studies documenting the complex and persistent nature of sharps-related injuries in healthcare workers. In the future, mandated reporting using standardized forms and consistent application of decision rules would facilitate a more thorough analysis of injury events.
Comparison of Waterless Hand Antisepsis Agents at Short Application Times: Raising the Flag of Concern
Authors: Dharan Sasi , Hugonnet Stéphane , Sax Hugo , Pittet Didier 
Published: March 2006

AbstractObjective:Although alcohol-based hand rinses and gels have recommended application times of 30 to 60 seconds, healthcare workers usually take much less time for hand hygiene. We compared the efficacies of four alcohol-based hand rubs produced in Europe (hand rinses A, B, and C and one gel formulation) with the efficacy of the European Norm 1500 (EN 1500) reference waterless hand antisepsis agent (60% 2-propanol) at short application times.Design:Comparative crossover study.Setting:Infection Control Program laboratory of a large tertiary-care teaching hospital.Participants:Twelve healthy volunteers.Intervention:Measurement of residual bacterial counts and log reduction factors following inoculation of fingertips with Staphylococcus aureus American Type Culture Collection (ATCC) 6538, Pseudomonas aeruginosa ATCC 15442, and a clinical isolate of Enterococcus faecalis.Results:All hand rinses satisfied EN 1500 standards following a single application for 15 and 30 seconds, but reduction factors for the gel formulation were significantly lower for all tested organisms (all P < .025).Conclusions:Under stringent conditions similar to clinical practice, all three hand rinses proved to be more efficacious than the marketed alcohol-based gel in reducing bacterial counts on hands. Further studies are necessary to determine the in vivo efficacy of alcohol-based gels and whether they are as efficacious as alcohol-based rinses in reducing the transmission of nosocomial infections.
Introduction of a Waterless Alcohol-Based Hand Rub in a Long-Term–Care Facility
Authors: Mody Lona , McNeil Shelly A. , Sun Rongjun , Bradley Suzanne F. , Kauffman Carol A. 
Published: March 2006

AbstractObjective:To examine the impact of introduction of an alcohol-based hand rub on hand hygiene knowledge and compliance and hand colonization of healthcare workers (HCWs) in a long-term-care facility (LTCF).Methods:Two floors of an LTCF participated. Ward A used the hand rub as an adjunct to soap and water; ward B was the control. HCWs' hands were cultured using the bag-broth technique forStaphylococcus aureus,gram-negative bacilli (GNB),Candida,and vancomycin-resistant enterococci (VRE). HCWs completed a questionnaire at baseline and after an educational intervention and introduction of rub.Results:Hand hygiene practices, knowledge, and opinions did not change after the educational or rub intervention. Ward A HCWs thought that the rub was faster (P= .002) and less drying (P= .04) than soap. Hand hygiene frequency did not differ at baseline between the two floors, but increased on ward A by the end of the study (P= .04). HCWs were colonized frequently with GNB (66%),Candida(41%), S.aureus(20%), and VRE (9%). Although colonization did not change from baseline on either ward, the rub was more effective in clearing GNB (P= .03) and S.aureus(P= .003). Nosocomial infection rates did not change.Conclusion:The alcohol-based hand rub was a faster, more convenient, less drying method of hand hygiene for HCWs in an LTCF, and it improved compliance. Although microbial colonization did not change, the rub was more efficacious in removing pathogens already present on the hands of HCWs.
Can Whipple's Disease Be Transmitted by Gastroscopes?
Authors: Scola Bernard La , Rolain Jean-Marc , Maurin Max , Raoult Didier 
Published: March 2006

AbstractObjective:To determine whether disinfection protocols currently used for gastroscopes are effective against cultures ofTropheryma whipplei.Design:The bactericidal activity of 2% glutaraldehyde and two peracetic acids on the Twist-Marseille strain ofT. whippleigrown in cell monolayers was determined.Patients:Two patients who were diagnosed as having Whipple's disease 3 years after they had had intestinal biopsies.Results:The disinfectants reduced bacteria by approximately 2 log10to 3 log10after 5 to 60 minutes of contact.Conclusion:The bactericidal activity of a disinfectant is usually considered significant if it causes a 5 log10or greater reduction in viable bacterial titers. Disinfecting gastroscopes with2%glutaraldehyde or peracetic acids for 20 minutes may be insufficient to prevent transmission ofT. whippleion the instruments or stop false-positive results on polymerase chain reaction.
Hand Antisepsis: Evaluation of a Sprayer System for Alcohol Distribution
Authors: Barrau Karine , Rovery Clarisse , Drancourt Michel , Brouqui Philippe 
Published: March 2006

AbstractObjective:To evaluate the usefulness of a new alcohol sprayer by comparing it with an individual bottle of alcohol. Patterns of use and perceptions among healthcare personnel were compared for the two products.Design:Observational study recording the volume of alcohol used and the compliance rate (frequency of hand antisepsis per number of opportunities), and a survey of healthcare workers' perceptions of the different hand hygiene strategies.Setting:A 20-bed medical unit in a public hospital in Marseille, France.Participants:Healthcare workers of an infectious disease unit.Interventions:Hand hygiene alcohol systems (sprayer vs individual bottle, 70% ethyl alcohol).Results:The sprayer was used more frequently than the individual bottle (12.6 vs 9.7 hand washes per day). With the sprayer system, compliance was 91% for physicians, 28% for nurses, and 8% for housekeeping personnel. Alcohol hand antisepsis was preferred to washing hands with soap and water in low-risk situations such as simple entrance into a room (91% vs 36%;P< 10-6) or simple contact with a patient (69% vs 40%;P< .005). The sprayer system was considered easier to use (95%), more hygienic (90%), and faster (92%), with a better tolerance than the individual bottle.Conclusion:The new alcohol sprayer should improve rapid hand antisepsis.
A Decontamination and Sterilization Protocol Employed During Reuse of Cardiac Electrophysiology Catheters Inactivates Human Immunodeficiency Virus
Authors: Druce Julian D. , Russell Jessica S. , Birch Christopher J. , Yates Lynette A. , Harper Richard W. , Smolich Joseph J. 
Published: March 2006

AbstractObjective:To assess the effect of a standard decontamination and sterilization protocol employed during reuse of cardiac electrophysiology (EP) catheters on human immunodeficiency virus (HIV).Setting:Public health viral research laboratory.Methods:Studies were performed on distal, electrode-containing segments of 40 EP catheters previously used in up to 10 clinical EP procedures. EP catheter segments were immersed for 1 hour in blood contaminated with a high titer of HIV. After air drying for 2 hours, subgroups of 8 EP catheters were subjected to either (1) no treatment, (2) washing in general purpose detergent, (3) washing in enzyme cleaner, (4) sterilization in ethylene oxide, or (5) the full protocol of sequential detergent-enzyme cleaner-ethylene oxide exposure. HIV infectivity after treatment was determined by measuring HIV RNA and, in cell culture studies, assessing HIV-induced cytopathic effects (CPEs) and supernatant HIV-specific p24 antigen content.Results:With no treatment, all catheters had high HIV RNA levels associated with CPEs and high p24 antigen levels. After washing in detergent, 5 of 8 catheters had HIV RNA detected, but without CPEs or p24 antigen. HIV RNA was detected in all catheters after washing in enzyme cleaner, with CPEs and a high p24 antigen level in 1 of 8 catheters. HIV RNA, CPEs, and p24 antigen were absent after ethylene oxide. After the full protocol, HIV RNA levels were undetectable (n = 7) or low (n = 1), without evidence of CPEs or p24 antigen.Conclusion:Appropriate decontamination and sterilization of EP catheters during reuse is highly effective in inactivating HIV.
Factors Related to Hospital Stay Among Patients With Nosocomial Infection Acquired in the Intensive Care Unit
Authors: Olaechea Pedro M. , Ulibarrena Miguel-Angel , Álvarez-Lerma Francisco , Insausti Jesús , Palomar Mercedes , De la Cal Miguel-Angel ,   ENVIN-UCI Study Group
Published: March 2006

AbstractObjectives:To assess the influence of nosocomial infection on length of stay in the intensive care unit (ICU) and to determine the relative effect of other factors on extra length of hospitalization associated with nosocomial infection.Design:Prospective cohort multicenter study in the context of the ENVIN-UCI project.Setting:Medical or surgical ICUs of 49 different hospitals in Spain.Methods:All consecutive patients (N = 6,593) admitted to ICUs of the participating hospitals who stayed for more than 24 hours during a 3-month period (from January 15 to April 15, 1996) were included. Length of ICU stay was compared between patients with and without nosocomial infections.Results:Uninfected patients (N = 5,868) had a median stay in the ICU of 3 days, whereas the median for infected patients (N = 725) was 17 days (P < .001). The median for infected patients with one episode of nosocomial infection was 13 days. The greatest length of stay (40 days) was among patients admitted to the ICU because of medical diseases, with an infection acquired before admission to the ICU, and with the largest number of nosocomial infection episodes. In extended stays, nosocomial infection was significantly associated with length of hospitalization (day 21; odds ratio, 22.38; 95% confidence interval, 16.6 to 30.4), whereas an effect of variables related to severity of illness on admission (Acute Physiology and Chronic Health Evaluation II score, urgent surgery, and infection prior to ICU admission) was not found.Conclusions:The presence of nosocomial infection and the number of infection episodes were the variables with the strongest association with prolonged hospital stay among ICU patients.