bluuebunny/crossref_metadata_2025 huggingface dataset:
G protein βγ-subunits activated by serotonin mediate presynaptic inhibition by regulating vesicle fusion properties
Authors: Photowala Huzefa , Blackmer Trillium , Schwartz Eric , Hamm Heidi E. , Alford Simon
Published: March 2006

Neurotransmitters are thought to be released as quanta, where synaptic vesicles deliver packets of neurotransmitter to the synaptic cleft by fusion with the plasma membrane. However, synaptic vesicles may undergo incomplete fusion. We provide evidence that G protein-coupled receptors inhibit release by causing such incomplete fusion. 5-hydroxytryptamine (5-HT) receptor signaling potently inhibits excitatory postsynaptic currents (EPSCs) between lamprey reticulospinal axons and their postsynaptic targets by a direct action on the vesicle fusion machinery. We show that 5-HT receptor-mediated presynaptic inhibition, at this synapse, involves a reduction in EPSC quantal size. Quantal size was measured directly by comparing unitary quantal amplitudes of paired EPSCs before and during 5-HT application and indirectly by determining the effect of 5-HT on the relationship between mean-evoked EPSC amplitude and variance. Results from FM dye-labeling experiments indicate that 5-HT prevents full fusion of vesicles. 5-HT reduces FM1-43 staining of vesicles with a similar efficacy to its effect on the EPSC. However, destaining of FM1-43-labeled vesicles is abolished by lower concentrations of 5-HT that leave a substantial EPSC. The use of a water-soluble membrane impermeant quenching agent in the extracellular space reduced FM1-43 fluorescence during stimulation in 5-HT. Thus vesicles contact the extracellular space during inhibition of synaptic transmission by 5-HT. We conclude that 5-HT, via free Gβγ, prevents the collapse of synaptic vesicles into the presynaptic membrane.
Encarsia species (Hymenoptera: Aphelinidae) of Australia and the Pacific Islands attacking Bemisia tabaci and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) – a pictorial key and descriptions of four new species
Authors: Schmidt S. , Naumann I.D. , De Barro P.J.
Published: March 2006

After the recent introduction of the pest whitefly Bemisia tabaci (Gennadius) biotype B into Australia, research was undertaken to study the parasitoids of the long established native B. tabaci and Trialeurodes vaporariorum (Westwood). The genus Encarsia species which are important biological control agents of whiteflies and hard scales. The taxonomy of the Encarsia species attacking B. tabaci and T. vaporariorum in Australia and the Pacific Islands is revised. DNA sequencing of the 28S D2 ribosomal DNA was used characterize species. Sixteen species are recognized, with 12 occurring in Australia, eight in the Pacific region, and four in both regions. All except one species (E. formosa Gahan) are new records for Australia. Four species are described as new from Australia: E. accenta & Naumann sp. n., E. adusta Schmidt & Naumann sp. n., E. oakeyensis Schmidt & Naumann sp. n., and E. ustulata Schmidt & Naumann sp. n. Diagnostic descriptions are given for all species and each species is illustrated. pictorial key is provided to allow the identification of species by non-specialists.
Genotypic interaction between resistance genes in wheat and virulence genes in the Hessian fly Mayetiola destructor (Diptera: Cecidomyiidae)
Authors: Bouhssini M. El , Hatchett J.H. , Cox T.S. , Wilde G.E.
Published: March 2006

The genotypic interaction between wheat resistance genes H3, H6, H7H8, H9 and virulence genes vH3, vH6, vH7vH8, vH9 of Hessian fly, Mayetiola destructor (Say), was studied in a growth chamber. Results showed plants homozygous and heterozygous for the H3 gene expressed a high level of resistance against homozygous avirulent and heterozygous larvae carrying the vH3 virulence allele. The H7H8 genes were highly effective in the homozygous condition, but displayed a level of resistance in the heterozygous condition. The H6 and H9 genes showed different levels of resistance against the reciprocal heterozygous larvae (vH6avH6a versus vH6avH6a and vH9avH9avH9avH9a). Adults reared from vH6avH6a and vH9avH9a larvae were all males, consistent with the vH6 and vH9 X-linkage. Plants homozygous for H3, H6, H7H8, and H9 allowed for greater larval survival of heterozygous larvae, which suggests that avirulence to these resistance genes is incompletely dominant. Greater survival of homozygous avirulent larvae on heterozygous plants (H3h3, H6h6, H7h7H8h8, H9h9) suggests incomplete dominance of these wheat genes. Survival of heterozygous along with homozygous virulent larvae would reduce selection pressure for virulence in Hessian fly populations infesting fields of resistant wheat cultivars. This would be expected to slow the in frequency of virulence alleles that often results from deployment of resistant cultivars.
Comparative development, longevity and population growth of exotic and native parasitoids of lepidopteran cereal stemborers in Kenya
Authors: Mbapila J.C. , Overholt W.A.
Published: March 2006

Studies on the effect of temperature on the development, longevity and population growth of Cotesia flavipes Cameron and Cotesia sesamiae (Cameron) indicated that the development of both Cotesia spp. from oviposition to cocoon formation and adult emergence was inversely to temperature. The longevity of the parasitoids was also inversely related to temperature. Both parasitoids lived longer when moisture and food (agar + honey/water) were provided. The mean number of females and total adult progeny produced by C. flavipes on two host were, in most cases, higher than C. sesamiae. The intrinsic rate of natural increase of C. flavipes was higher than that of C. sesamiae.
Oviposition behaviour and host colony size discrimination in Episyrphus balteatus (Diptera: Syrphidae)
Authors: Sutherland J.P. , Sullivan M.S. , Poppy G.M.
Published: March 2006

Three bioassays were used to examine the oviposition behaviour of the hoverfly, Episyrphus balteatus (Degeer) in which various stimuli purported to influence host assessment and choice were tested. Episyrphus balteatus failed to exhibit enhanced behavioural responses, terms of approaches and landings, to artificial leaves with the highest numbers of aphids, suggesting that females are merely responding to the colour of the artificial leaves. A density-dependent oviposition response was reported in a second bioassay using whole bean plants, although there an asymptotic relationship. Syrphid responses, which were measured by oviposition over a five-day period, were greatest towards those plants with the highest number of aphids. In a final series of trials, gravid female E. balteatus showed a behavioural preference for filter papers with the greatest honeydew concentrations (0.26 mg μl−1 honeydew). More time was spent in the treated areas and syrphids demonstrated more proboscis and ovipositor extensions in these treatments. These bioassays provided an opportunity to isolate some of the individual of decision-making by female E. balteatus during egg-laying behaviour. A greater understanding of natural enemy behaviour is essential before enhanced control of pest populations in the field can be established.
Desiccation resistance in pre-diapause, diapause and post-diapause larvae of Choristoneura fumiferana (Lepidoptera: Tortricidae)
Authors: Bauce É , Han E.
Published: March 2006

Desiccation resistance was examined in pre-diapause, diapause and post-diapause larvae of the spruce budworm, Choristoneura fumiferana (Clemens), in terms of passive water evaporation under three desiccation conditions: freeze-drying, desiccant-drying at 2°C and desiccant-drying 18°C. Diapausing second instar larvae and post-diapause non-feeding second instar larvae showed strongest desiccation resistance: a significant amount of water was retained after repeated drying under desiccating conditions, while pre-diapause first instar larvae and post-diapause feeding instar larvae lost almost all their water content after one or two drying cycles. A hibernaculum covering had no effect on water evaporation. While dead larvae tended to lose significantly more water than their living counterparts, particularly among first instar larvae, such an impact much weaker among diapausing second instar larvae. Desiccation resistance was lost when post-diapause second instar larvae were allowed access to water while the level of desiccation resistance was maintained or enhanced when the larvae did not have access to water. These results are discussed the context of overwintering ecology of the species and possible mechanisms for the desiccation resistance are also discussed.
Body size as an indicator of parasitoid quality in male and female Anagyrus kamali (Hymenoptera: Encyrtidae)
Authors: Sagarra L.A. , Vincent C. , Stewart R.K.
Published: March 2006

The parasitoid Anagyrus kamali Moursi was recently introduced into the Caribbean as a biological control agent against the hibiscus mealybug, Maconellicoccus hirsutus Green. In the laboratory, parasitoid size, as measured by left hind tibia length, was positively correlated several indicators of the parasitoid‘s fitness: longevity, mating preference, fecundity, reproductive longevity, progeny emergence and sex-ratio. When fed ad libidum with honey drops, large male parasitoids lived significantly longer (29.1 ± 6.5 days) than small ones ± 5.7 days). Large females also lived significantly longer (35.4 ± 10 days) than small females (27.9 ± 9.6 days). Females showed no significant mating preference between large and small males. Lifetime fecundity was positively correlated with the size of adult females ranged from 37 ± 21 eggs for small females to 96 ± 43 eggs for large ones. The reproductive longevity, daily oviposition rate, and number of progeny were also higher among large parasitoids. The sex ratio of progeny from small female parasitoids was higher (0.76 ± than that of large individuals (0.47 ± 0.18).
First contact session outcomes in primary care psychological therapy and counselling services
Authors: Cahill Jane , Potter Steve , Mullin Tracy
Published: March 2006

Evidence in the literature suggests that some groups have greater difficulty accessing psychological treatment than others. The present study set out to provide benchmarks from the CORE National Research Database, focussing on four primary outcomes following a client's first contact session – (1) accepted for therapy, (2) assessment only, (3) referred to another service, (4) unsuitable for therapy. Data from 34 primary care counselling services were collected which had used CORE‐PC as a service resource for at least two years. For each of the four assessment outcomes, the mean, standard deviation and 25th, 50th and 75th percentiles were calculated. Across the 34 services, an average of 81% clients were accepted for therapy with 25th, 50th, and 75th percentile values of 74, 82 and 89% respectively. The results indicate that working with benchmarks is an area in need of further research. Implications for policy and practice are discussed and attention given to the client's experience of seeking therapy.
When clients and practitioners have differing views of risk: Benchmarks for improving assessment and practice
Authors: Bewick Bridgette M. , McBride Jenny , Barkham Michael
Published: March 2006

The assessment of risk is a top priority within routine counselling and psychotherapy services. However, staff often receive little training in this area. Research suggests that differences between practitioner‐rated and client self‐report assessments are to be expected and has indicated that the rates of difference can be relatively high (i.e., >50%). However, no national benchmarks have yet been presented which allow both practitioners and services to assess their degree of difference between client‐ and therapist‐ratings of risk. This study uses data drawn from the CORE National Research Database and the risk domain of the CORE‐OM (n=25338) to address this issue. Percentage of difference in assessment rates are presented to enable services to compare their rates of difference with those obtained in other services. The CORE‐OM risk domain identified 44% of clients as ‘at risk’ while the practitioner assessment identified 10% of clients as being ‘at risk’. For the overall sample, 18% of clients were classified by the practitioner as presenting no risk when the CORE‐OM risk domain identified them at risk. There were large variations between services. The practical use and implications of the results presented are discussed by managers of NHS primary care counselling services.
Client initiated termination of therapy at NHS primary care counselling services
Authors: Connell Janice , Grant Stewart , Mullin Tracy
Published: March 2006

The main aim of this paper is to provide estimated benchmarks for unplanned endings for primary care counselling services using data drawn from the CORE National Research Database. Due to the problem of missing data, benchmarks are provided for ‘declared’ therapy endings and ‘estimated’ therapy endings. ‘Declared’ therapy endings are where the practitioner has provided data; ‘estimated’ therapy endings take into account missing data where clients are more likely to have had an unplanned rather than a planned ending to therapy. The average ‘declared’ rate of unplanned endings was calculated at 32% with a high rate determined as 40% or higher and a low rate as 21% or lower. The average ‘estimated’ rate of unplanned endings was calculated at 50% with a high rate determined as 58% or higher and a low rate as 38% or lower. It is likely that the true average, high and low rates of unplanned endings fall between the two sets of figures.
Sos-mediated activation of rac1 by p66shc
Authors: Khanday Firdous A. , Santhanam Lakshmi , Kasuno Kenji , Yamamori Tohru , Naqvi Asma , DeRicco Jeremy , Bugayenko Artem , Mattagajasingh Ilwola , Disanza Andrea , Scita Giorgio , Irani Kaikobad
Published: March 2006

The Son of Sevenless 1 protein (sos1) is a guanine nucleotide exchange factor (GEF) for either the ras or rac1 GTPase. We show that p66shc, an adaptor protein that promotes oxidative stress, increases the rac1-specific GEF activity of sos1, resulting in rac1 activation. P66shc decreases sos1 bound to the growth factor receptor bound protein (grb2) and increases the formation of the sos1–eps8–e3b1 tricomplex. The NH2-terminal proline-rich collagen homology 2 (CH2) domain of p66shc associates with full-length grb2 in vitro via the COOH-terminal src homology 3 (C-SH3) domain of grb2. A proline-rich motif (PPLP) in the CH2 domain mediates this association. The CH2 domain competes with the proline-rich COOH-terminal region of sos1 for the C-SH3 domain of grb2. P66shc-induced dissociation of sos1 from grb2, formation of the sos1–eps8–e3b1 complex, rac1-specific GEF activity of sos1, rac1 activation, and oxidative stress are also mediated by the PPLP motif in the CH2 domain. This relationship between p66shc, grb2, and sos1 provides a novel mechanism for the activation of rac1.
Neuron to glia signaling triggers myelin membrane exocytosis from endosomal storage sites
Authors: Trajkovic Katarina , Dhaunchak Ajit Singh , Goncalves José T. , Wenzel Dirk , Schneider Anja , Bunt Gertrude , Nave Klaus-Armin , Simons Mikael
Published: March 2006

During vertebrate brain development, axons are enwrapped by myelin, an insulating membrane produced by oligodendrocytes. Neuron-derived signaling molecules are temporally and spatially required to coordinate oligodendrocyte differentiation. In this study, we show that neurons regulate myelin membrane trafficking in oligodendrocytes. In the absence of neurons, the major myelin membrane protein, the proteolipid protein (PLP), is internalized and stored in late endosomes/lysosomes (LEs/Ls) by a cholesterol-dependent and clathrin-independent endocytosis pathway that requires actin and the RhoA guanosine triphosphatase. Upon maturation, the rate of endocytosis is reduced, and a cAMP-dependent neuronal signal triggers the transport of PLP from LEs/Ls to the plasma membrane. These findings reveal a fundamental and novel role of LEs/Ls in oligodendrocytes: to store and release PLP in a regulated fashion. The release of myelin membrane from LEs/Ls by neuronal signals may represent a mechanism to control myelin membrane growth.
A Maurer's cleft–associated protein is essential for expression of the major malaria virulence antigen on the surface of infected red blood cells
Authors: Cooke Brian M. , Buckingham Donna W. , Glenister Fiona K. , Fernandez Kate M. , Bannister Lawrence H. , Marti Matthias , Mohandas Narla , Coppel Ross L.
Published: March 2006

The high mortality of Plasmodium falciparum malaria is the result of a parasite ligand, PfEMP1 (P. falciparum) erythrocyte membrane protein 1), on the surface of infected red blood cells (IRBCs), which adheres to the vascular endothelium and causes the sequestration of IRBCs in the microvasculature. PfEMP1 transport to the IRBC surface involves Maurer's clefts, which are parasite-derived membranous structures in the IRBC cytoplasm. Targeted gene disruption of a Maurer's cleft protein, SBP1 (skeleton-binding protein 1), prevented IRBC adhesion because of the loss of PfEMP1 expression on the IRBC surface. PfEMP1 was still present in Maurer's clefts, and the transport and localization of several other Maurer's cleft proteins were unchanged. Maurer's clefts were altered in appearance and were no longer found as close to the periphery of the IRBC. Complementation of mutant parasites with sbp1 led to the reappearance of PfEMP1 on the IRBC surface and the restoration of adhesion. Our results demonstrate that SBP1 is essential for the translocation of PfEMP1 onto the surface of IRBCs and is likely to play a pivotal role in the pathogenesis of P. falciparum malaria.
RNA granules
Authors: Anderson Paul , Kedersha Nancy
Published: March 2006

Cytoplasmic RNA granules in germ cells (polar and germinal granules), somatic cells (stress granules and processing bodies), and neurons (neuronal granules) have emerged as important players in the posttranscriptional regulation of gene expression. RNA granules contain various ribosomal subunits, translation factors, decay enzymes, helicases, scaffold proteins, and RNA-binding proteins, and they control the localization, stability, and translation of their RNA cargo. We review the relationship between different classes of these granules and discuss how spatial organization regulates messenger RNA translation/decay.
Orphan nuclear receptor TR3/Nur77 regulates VEGF-A–induced angiogenesis through its transcriptional activity
Authors: Zeng Huiyan , Qin Liuliang , Zhao Dezheng , Tan Xiaolian , Manseau Eleanor J. , Van Hoang Mien , Senger Donald R. , Brown Lawrence F. , Nagy Janice A. , Dvorak Harold F.
Published: March 2006

Vascular endothelial growth factor (VEGF)-A has essential roles in vasculogenesis and angiogenesis, but the downstream steps and mechanisms by which human VEGF-A acts are incompletely understood. We report here that human VEGF-A exerts much of its angiogenic activity by up-regulating the expression of TR3 (mouse homologue Nur77), an immediate-early response gene and orphan nuclear receptor transcription factor previously implicated in tumor cell, lymphocyte, and neuronal growth and apoptosis. Overexpression of TR3 in human umbilical vein endothelial cells (HUVECs) resulted in VEGF-A–independent proliferation, survival, and induction of several cell cycle genes, whereas expression of antisense TR3 abrogated the response to VEGF-A in these assays and also inhibited tube formation. Nur77 was highly expressed in several types of VEGF-A–dependent pathological angiogenesis in vivo. Also, using a novel endothelial cell-selective retroviral targeting system, overexpression of Nur77 DNA potently induced angiogenesis in the absence of exogenous VEGF-A, whereas Nur77 antisense strongly inhibited VEGF-A–induced angiogenesis. B16F1 melanoma growth and angiogenesis were greatly inhibited in Nur77−/− mice. Mechanistic studies with TR3/Nur77 mutants revealed that TR3/Nur77 exerted most of its effects on cultured HUVECs and its pro-angiogenic effects in vivo, through its transactivation and DNA binding domains (i.e., through transcriptional activity).
A polymorphism in theEAAT2promoter is associated with higher glutamate concentrations and higher frequency of progressing stroke
Authors: Mallolas Judith , Hurtado Olivia , Castellanos Mar , Blanco Miguel , Sobrino Tomás , Serena Joaquín , Vivancos José , Castillo José , Lizasoain Ignacio , Moro María A. , Dávalos Antoni
Published: March 2006

It remains unclear why some individuals are susceptible to excitotoxicity after stroke. A possible explanation is impaired glutamate uptake. We have found a highly prevalent polymorphism in the promoter of the glutamate transporter EAAT2 gene that abolishes a putative regulatory site for activator protein–2 (AP-2) and creates a new consensus binding site for the repressor transcription factor GC-binding factor 2 (GCF2). The mutant genotype is associated with increased plasma glutamate concentrations and with a higher frequency of early neurological worsening in human stroke. After transfection into astrocytes, the mutant promoter was not activated by AP-2 and was effectively repressed by GCF2, and its activity in the presence of GCF2 was reduced when compared with the AP-2–cotransfected wild-type promoter. We also show that GCF2 is expressed in ischemic rat brain, suggesting that decreased glutamate uptake occurs in individuals carrying the mutation after stroke. These findings may explain individual susceptibility to excitotoxic damage after stroke as well as the failure of glutamate antagonists in those patients without this polymorphism.
T-bet regulates Th1 responses through essential effects on GATA-3 function rather than on IFNG gene acetylation and transcription
Authors: Usui Takashi , Preiss Jan C. , Kanno Yuka , Yao Zheng Ju , Bream Jay H. , O'Shea John J. , Strober Warren
Published: March 2006

T helper type 1 (Th1) development is facilitated by interrelated changes in key intracellular factors, particularly signal transducer and activator of transcription (STAT)4, T-bet, and GATA-3. Here we show that CD4+ cells from T-bet−/− mice are skewed toward Th2 differentiation by high endogenous GATA-3 levels but exhibit virtually normal Th1 differentiation provided that GATA-3 levels are regulated at an early stage by anti–interleukin (IL)-4 blockade of IL-4 receptor (R) signaling. In addition, under these conditions, Th1 cells from T-bet−/− mice manifest IFNG promotor accessibility as detected by histone acetylation and deoxyribonuclease I hypersensitivity. In related studies, we show that the negative effect of GATA-3 on Th1 differentiation in T-bet−/− cells arises from its ability to suppress STAT4 levels, because if this is prevented by a STAT4-expressing retrovirus, normal Th1 differentiation is observed. Finally, we show that retroviral T-bet expression in developing and established Th2 cells leads to down-regulation of GATA-3 levels. These findings lead to a model of T cell differentiation that holds that naive T cells tend toward Th2 differentiation through induction of GATA-3 and subsequent down-regulation of STAT4/IL-12Rβ2 chain unless GATA-3 levels or function is regulated by T-bet. Thus, the principal function of T-bet in developing Th1 cells is to negatively regulate GATA-3 rather than to positively regulate the IFNG gene.
Improving Patient Safety: Resource Availability and Application for Reducing the Incidence of Healthcare-Associated Infection
Authors: Christenson Marly , Hitt John A. , Abbott Gordon , Septimus Edward J. , Iversen Nancy
Published: March 2006

Objective.

VHA Mountain States conducted a survey and analysis of infection control (IC) staffing resources, organizational structures, and clinical processes related to reducing the incidence of healthcare-associated infections (HAIs) in community healthcare facilities.

Methods.

Member participation was solicited for 2 study components. The first was a survey of demographic characteristics regarding the type and size of the facility and the structure and functions of IC departments. The second was an observational study of infection prevention practices related to general hand hygiene (GHH), ventilator-associated pneumonia (VAP), catheter-related bloodstream infection (CRBSI), and catheter-related urinary tract infection (CRUTI).

Results.

A total of 31 not-for-profit community healthcare facilities submitted data; the number of beds in participating centers ranged from less than 50 beds (1 facility) to more than 500 beds (7 facilities). IC department staffing ranged from 0.3 to 5.0 full-time equivalents. There was a positive correlation between average daily census and IC staffing (r = .879; P<.001). Observational studies revealed that compliance with the use of alcohol-based hand rubs (77%) was significantly better than compliance with the use of soap and water (64%; P<.001). Seven (30%) of 23 organizations observed 90% or better compliance with VAP process measures; 7 of 27 (26%) observed 90% or better compliance with guidelines for preventing CRBSI; and 14 (56%) demonstrated proper placement of urinary drainage bags at least 90% of the time.

Conclusions.

There was variation in IC department structure and processes among the participating organizations. Infection prevention practices were inconsistent. These findings emphasize the need for more-effective implementation of current evidence-based recommendations for preventing HAIs and reducing the risk of harm to patients.
Favorable Impact of an Infection Control Network on Nosocomial Infection Rates in Community Hospitals
Authors: Kaye Keith S. , Engemann John J. , Fulmer Evelyn M. , Clark Connie C. , Noga Edwin M. , Sexton Daniel J.
Published: March 2006

Objective.

To describe an infection control network (the Duke Infection Control Outreach Network [DICON]) and its impact on nosocomial infection rates in community hospitals.

Design.

Prospective cohort study of rates of nosocomial infections and exposures of employees to bloodborne pathogens in hospitals during the first 3 years of their affiliation with DICON. Attributable cost and mortality estimates were obtained from published studies.

Setting.

Twelve community hospitals in North Carolina and Virginia.

Results.

During the first 3 years of hospital affiliation with DICON, annual rates of nosocomial bloodstream infections at study hospitals decreased by 23% (P = .009). Annual rates of nosocomial infection and colonization due to methicillin-resistant Staphylococcus aureus decreased by 22% (P = .002), and rates of ventilator-associated pneumonia decreased by 40% (P = .001). Rates of exposure of employees to bloodborne pathogens decreased by 18% (P = .003).

Conclusions.

The establishment of an infection control network within a group of community hospitals was associated with substantial decreases in nosocomial infection rates. Standard surveillance methods, frequent data analysis and feedback, and interventions based on guidelines and protocols from the Centers for Disease Control and Prevention were the principal strategies used to achieve these reductions. In addition to lessening the adverse clinical outcomes due to nosocomial infections, these reductions substantially decreased the economic burden of infection: the decline in nosocomial bloodstream infections and ventilator-associated pneumonia alone yielded potential savings of $578,307 to $2,195,954 per year at the study hospitals.
Controlling Use of Antimicrobials in a Community Teaching Hospital
Authors: Philmon Carla , Smith Terri , Williamson Sharon , Goodman Edward
Published: March 2006

Objective.

To test the hypothesis that antibiotic use could be controlled or improved in a community teaching hospital, with improvement defined as reductions in overall use, overall cost, and antimicrobial resistance.

Design.

Interventional study with historical comparison.

Setting.

A not-for-profit, 900-bed community general hospital with residents in medicine, surgery, obstetrics-gynecology, and psychiatry.

Participants.

Physicians who requested any of the targeted antibiotics.

Interventions.

Three categories of inpatient antibiotic orders were monitored beginning in April 2001: conversion from intravenous to oral administration for selected highly bioavailable antimicrobials, cessation of perioperative prophylaxis within 24 hours for patients undergoing clean and clean-contaminated surgery, and consultation with an infectious diseases physician before continuing administration of selected drugs beyond 48 hours. Data were analyzed after the first 33 months. Patient outcomes were reviewed during the hospital stay and at readmission if it occurred within 30 days after discharge.

Results.

From April 2001 through December 2003, a total of 1426 requests for antimicrobial therapy met criteria for intervention. Overall physician compliance with the program was 76%, ranging from 57% for perioperative prophylaxis to 92% for intravenous to oral conversion. Antimicrobial costs per patient-day decreased by 31%, from $13.67 in 2000 (before program implementation) to $9.41 in 2003. Total savings in acquisition costs were $1,841,203 for the 3-year period. Resistance to numerous drugs among Klebsiella pneumoniae isolates was also significantly reduced.

Conclusions.

A program to improve the use of antibiotics in a community hospital was successful in reducing overall use, overall cost, and antimicrobial resistance.
Influenza Vaccination of Healthcare Workers in the United States, 1989-2002
Authors: Walker Frances J. , Singleton James A. , Lu Pengjun , Wooten Karen G. , Strikas Raymond A.
Published: March 2006

Objectives.

We sought to estimate influenza vaccination coverage among healthcare workers (HCWs) in the United States during 1989-2002 and to identify factors associated with vaccination in this group. The Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for HCWs to reduce transmission of influenza to patients at high risk for serious complications of influenza.

Design.

Analysis of cross-sectional data from 1989-2002 surveys conducted by the National Health Interview Survey (NHIS). The outcome measure was self-reported influenza vaccination in the past 12 months. Bivariate and multivariate analysis of 2002 NHIS data.

Setting.

Household interviews conducted during 1989-2002, weighted to reflect the noninstitutionalized, civilian US population.

Participants.

Adults aged 18 years or older participated in the study. A total of 2,089 were employed in healthcare occupations or settings in 2002, and 17,160 were employed in nonhealthcare occupations or settings.

Results.

The influenza vaccination rate among US HCWs increased from 10.0% in 1989 to 38.4% in 2002, with no significant change since 1997. In a multivariate model that included data from the 2002 NHIS, factors associated with a higher rate of influenza vaccination among HCWs aged 18-64 years included age of 50 years or older (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.1), hospital employee status (OR, 1.5; 95% CI, 1.2-1.9), 1 or more visits to the office of a healthcare professional in the past 12 months (OR, 1.5; 95% CI, 1.1-2.2), receipt of employer-provided health insurance (OR, 1.5; 95% CI, 1.1-2.1), a history of pneumococcal vaccination (OR, 3.9; 95% CI, 2.5-6.1), and history of hepatitis B vaccination (OR, 1.9; 95% CI, 1.4-2.4). Non-Hispanic black persons were less likely to be vaccinated (OR, 0.6; 95% CI, 0.5-0.9) than non-Hispanic white persons. There were no significant differences in vaccination levels according to HCW occupation category.

Conclusions.

Influenza immunization among HCWs reached a plateau during 1997-2002. New strategies are needed to encourage US HCWs to receive influenza vaccination to prevent influenza illness in themselves and transmission of influenza to vulnerable patients.
Is Influenza an Influenza-Like Illness? Clinical Presentation of Influenza in Hospitalized Patients
Authors: Babcock Hilary M. , Merz Liana R. , Fraser Victoria J.
Published: March 2006

Background.

Early recognition of influenza virus infection in hospitalized patients can prevent nosocomial transmission.

Objective.

To determine the clinical presentation of influenza in hospitalized patients.

Design.

Case series. Data were collected retrospectively from medical records and included demographic information, comorbidities, clinical symptoms and signs, microbiologic test results, and outcomes (including pneumonia and intensive care unit [ICU] admission).

Setting.

A 1,400-bed teaching hospital.

Patients.

A total of 207 inpatients who received a diagnosis of influenza virus infection during 3 seasons from 2000 to 2003.

Results.

Over the course of 3 seasons, 207 patients received a diagnosis of influenza (186 were infected with influenza A virus, and 21 were infected with influenza B virus). The most commonly reported symptoms were cough (186 patients [90%]) and subjective fever (137 patients [66%]); 124 patients (60%) had a documented temperature of 37.8°C or greater before influenza was diagnosed. Sore throat was uncommon (44 patients [21%]). Centers for Disease Control and Prevention (CDC) criteria for influenza-like illness (ILI)–temperature 37.8°C or greater and either cough or sore throat–were met by 107 patients (51%). There were no differences in the proportion of patients who met ILI criteria with respect to age, sex, season, influenza virus type, or time to diagnosis in the hospital. Most patients (150 [72%]) received acetaminophen. Only 41 patients (20%) had positive results of clinical cultures; 178 patients (86%) received antibiotic therapy. Fifty-six patients (27%) had pneumonia: 36 (17%) required admission to the ICU, and 25 (12%) required ventilatory support. Patients with pulmonary disease were more likely to require ventilatory support (12 [26%] vs 13 [8%]; P = .003).

Conclusions.

Only half of hospitalized patients with influenza met CDC criteria for ILI. These criteria may be more appropriate in outpatient settings. A high index of suspicion is needed to recognize influenza in hospitalized patients.
Outbreak of Toxic Anterior Segment Syndrome Following Cataract Surgery Associated With Impurities in Autoclave Steam Moisture
Authors: Hellinger Walter C. , Hasan Saiyid A. , Bacalis Laura P. , Thornblom Deborah M. , Beckmann Susan C. , Blackmore Carina , Forster Terri S. , Tirey Jason F. , Ross Mary J. , Nilson Christian D. , Mamalis Nick , Crook Julia E. , Bendel Rick E. , Shetty Rajesh , Stewart Michael W. , Bolling James P. , Edelhauser Henry F.
Published: March 2006

Background.

Toxic anterior segment syndrome (TASS), a complication of cataract surgery, is a sterile inflammation of the anterior chamber of the eye. An outbreak of TASS was recognized at an outpatient surgical center and its affiliated hospital in December 2002.

Methods.

Medical records of patients who underwent cataract surgery during the outbreak were reviewed, and surgical team members who participated in the operations were interviewed. Potential causes of TASS were identified and eliminated. Feedwater from autoclave steam generators and steam condensates were analyzed by use of spectroscopy and ion chromatography.

Results.

During the outbreak, 8 (38%) of 21 cataract operations were complicated by TASS, compared with 2 (0.07%) of 2,713 operations performed from January 1996 through November 2002. Results of an initial investigation suggested that cataract surgical equipment may have been contaminated by suboptimal equipment reprocessing or as a result of personnel changes. The frequency of TASS decreased (1 of 44 cataract operations) after reassignment of personnel and revision of equipment reprocessing procedures. Further investigation identified the presence of impurities (eg, sulfates, copper, zinc, nickel, and silica) in autoclave steam moisture, which was attributed to improper maintenance of the autoclave steam generator in the outpatient surgical center. When impurities in autoclave steam moisture were eliminated, no cases of TASS were observed after more than 1,000 cataract operations.

Conclusion.

Suboptimal reprocessing of cataract surgical equipment may evolve over time in busy, multidisciplinary surgical centers. Clinically significant contamination of surgical equipment may result from inappropriate maintenance of steam sterilization systems. Standardization of protocols for reprocessing of cataract surgical equipment may prevent outbreaks of TASS and may be of assistance during outbreak investigations.
Use of Local Community Hospital Data for Surveillance of Antimicrobial Resistance
Authors: Farner Susan M.
Published: March 2006

We sought to determine whether antimicrobial susceptibility data from a nonteaching community hospital could be used to detect statistically significant local increases in resistance among Streptococcus pneumoniae over a 5-year period. Minimum inhibitory concentrations (MICs) of penicillin and ceftriaxone from 1997-1998 were compared with those from 2000-2001. MICs of penicillin and ceftriaxone for organisms collected in a nonteaching community hospital in central Illinois were used for analysis. The hospital has 224 beds and a catchment area of approximately 40 miles. There were significant increases in MICs of penicillin and ceftriaxone between 1997-1998 and 2000-2001. The MIC of penicillin increased from 0.042 to 0.121 μg/mL (P = .001; 95% confidence interval, -1.713 to -0.388), and the MIC of ceftriaxone increased from 0.028 to 0.071μg/mL (P = .005; 95% confidence interval, -1.353 to -0.188). There were no significant changes in the percentage of S. pneumoniae isolates that were resistant, intermediate, or susceptible to penicillin and ceftriaxone. MIC data from a community hospital can be used to detect local increases in the rate of resistance before antibiogram data show significant changes. This information is important for demonstrating to physicians the need to review local antibiotic use in the attempt to slow the development of resistant organisms in the community.
A Nosocomial Outbreak ofEscherichia coliProducing CTX-M-15 and OXA-30β-Lactamase
Authors: Pai Hyunjoo , Kim Mi Ran , Seo Mi-Ran , Choi Tae Yeal , Oh Sung Hee
Published: March 2006

During a survey of the prevalent subtypes of extended-spectrumβ-lactamases in a university hospital in Korea, a nosocomial outbreak ofEscherichia coliproducing CTX-M-15 and OXA-30β-lactamases was detected. The outbreak comprised various infections, including bloodstream infections and colonization, and persisted for several months in various areas of the hospital.
Diminished Susceptibility to Daptomycin Accompanied by Clinical Failure in a Patient With Methicillin-Resistant Staphylococcus aureus Bacteremia
Authors: Hirschwerk David , Ginocchio Christine C. , Bythrow Maureen , Condon Susan
Published: March 2006

We cared for a patient with methicillin-resistant Staphylococcus aureus bacteremia who experienced clinical failure with daptomycin. The failure was accompanied by progressive elevation of the daptomycin minimum inhibitory concentration during treatment. DNA fingerprinting confirmed that the minimum inhibitory concentration elevation occurred within the same strain of methicillin-resistant Staphylococcus aureus. This observation provides important new information to clinicians who adopt this promising drug for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus.
Limiting the Emergence of Extended-Spectrumβ–Lactamase-Producing Enterobacteriaceae: Influence of Patient Population Characteristics on the Response to Antimicrobial Formulary Interventions
Authors: Lipworth Adam D. , Hyle Emily P. , Fishman Neil O. , Nachamkin Irving , Bilker Warren B. , Marr Ann Marie , Larosa Lori A. , Kasbekar Nishaminy , Lautenbach Ebbing
Published: March 2006

Background.

Effective methods to control the emergence of extended-spectrumβ-lactamase-producingEscherichia coliandKlebsiellaspecies (ESBL-EK) remain unclear. Variations in the patient populations at different hospitals may influence the effect of antimicrobial formulary interventions.

Methods.

To examine variations across hospitals in the response to antimicrobial interventions (ie, restriction of ceftazidime and ceftriaxone) designed to curb the spread of ESBL-EK, we conducted a 5-year quasi-experimental study. This study was conducted at 2 hospitals within the same health system: Hospital A is a 625-bed academic medical center, and Hospital B is a 344-bed urban community hospital. All adult patients with a healthcare-acquired clinical culture of ESBL-EK from July 1, 1997 through December 31, 2002 were included.

Results.

After the interventions, the use of ceftriaxone decreased by 86% at Hospital A and by 95% at Hospital B, whereas the use of ceftazidime decreased by 95% at Hospital A and by 97% at Hospital B. The prevalence of ESBL-EK at Hospital A decreased by 45% (P< .001), compared with a 22% decrease at Hospital B (P= .36). The following variables were significantly more common among ESBL-EK-infected patients at Hospital B: residence in a long-term care facility (adjusted odds ratio, 3.77 [95% confidence interval, 1.70-8.37]), advanced age (adjusted odds ratio, 1.04 [95% confidence interval, 1.01-1.06]), and presence of a decubitus ulcer (adjusted odds ratio, 4.13 [95% confidence interval, 1.97-8.65]).

Conclusions.

The effect of antimicrobial formulary interventions intended to curb emergence of ESBL-EK may differ substantially across institutions, perhaps as a result of differences in patient populations. Variability in the epidemiological profiles of ESBL-EK isolates at different hospitals must be considered when designing interventions to respond to these pathogens.
Risk of Environmental and Healthcare Worker Contamination With Vancomycin-Resistant Enterococci During Outpatient Procedures and Hemodialysis
Authors: Grabsch Elizabeth A. , Burrell Laurelle J. , Padiglione Alexander , O'Keeffe Jason M. , Ballard Susan , Grayson M. Lindsay
Published: March 2006

Objective.

To assess the risk of environmental and healthcare worker (HCW) contamination with vancomycin-resistant enterococci (VRE) during outpatient procedures performed on fecally continent patients currently colonized with VRE (cVRE) or previously colonized with VRE (pVRE).

Design.

Observational study.

Setting.

Outpatient consultation and radiology rooms and the hemodialysis unit in a university teaching hospital.

Patients.

Fecally continent cVRE and pVRE patients.

Interventions.

Both cVRE and pVRE patients attended standardized mock outpatient consultations and routine hemodialysis sessions in an area that had been thoroughly cleaned and microbiologically confirmed to be free of VRE contamination. After each session, the patient, environment, and participating HCW were tested for VRE contamination.

Results.

Fourteen cVRE patients participated in 49 mock outpatient consultation sessions and radiology sessions or 26 actual hemodialysis sessions, and 7 pVRE patients participated in 28 outpatient consultation sessions. Sessions with cVRE patients had higher rates of contamination of the environment (chair cultures were positive for VRE in 36% of outpatient consultation sessions, 58% of hemodialysis sessions; couch cultures were positive in 48% of outpatient consultation sessions, 42% of radiology sessions, and 45% of hemodialysis sessions), contamination of HCW gowns (gown cultures were positive in 20% of outpatient consultation sessions, 4% of radiology sessions, and 30% of hemodialysis sessions), and contamination of patients' own hands (hand cultures were positive in 36% of outpatient consultation sessions, 25% of radiology sessions, and 54% of hemodialysis sessions). Overall, contamination rates associated with pVRE patients attendance at outpatient consultations were 12% of those noted for cVRE patients (odds ratio, 0.10; 95% confidence interval, 0.03-0.42;P= .001).

Conclusions.

Given the nature of the contamination risk posed by fecally continent cVRE patients undergoing outpatient procedures, infection control measures should focus on effective HCW and patient hand hygiene and chair and couch cleaning, to minimize transmission of VRE.
Bacteriological Monitoring of Water Reservoirs in Oxygen Humidifiers: Safety of Prolonged and Multipatient Use of Prefilled Disposable Oxygen Humidifier Bottles
Authors: Kobayashi Nobuharu , Yamazaki Tsutomu , Maesaki Shigefumi
Published: March 2006

Bacterial colony counts in water specimens from oxygen humidifiers that used reusable water reservoirs were compared with counts in water specimens from humidifiers that used prefilled disposable reservoir bottles to evaluate the effects of prolonged and multipatient use of humidifiers. Bacteria were detected after 1 week of operation in water specimens collected from many humidifiers with reusable reservoirs, but no bacteria were detected in water specimens from disposable bottles for up to 12 weeks during use of the humidifier by multiple patients.
Scalar–tensor–vector gravity theory
Authors: Moffat J W
Published: March 2006

A covariant scalar–tensor–vector gravity theory is developed which allows the gravitational constant
G, a vector field
coupling ω and the
vector field mass μ
to vary with space and time. The equations of motion for a test particle lead to a modified
gravitational acceleration law that can fit galaxy rotation curves and cluster data without
non-baryonic dark matter. The theory is consistent with solar system observational tests.
The linear evolutions of the metric, vector field and scalar field perturbations and their
consequences for the observations of the cosmic microwave background are investigated.
Positive assortative mating between recently described sympatric morphs of Icelandic sticklebacks
Authors: Ólafsdóttir Gudbjörg Á , Ritchie Michael G , Snorrason Sigurdur S
Published: March 2006

Recently, models of sympatric speciation have suggested that assortative mating can develop between sympatric morphs due to divergence in an ecologically important character. For example, in sympatric pairs of threespine stickleback (Gasterosteus aculeatusL.) size-assortative mating seems to be instrumental in reproductive isolation. Here, we examine courtship behaviour and assortative mating of newly described sympatric stickleback morphs in Lake Thingvallavatn, Iceland. We find that the two morphs show strong positive assortative mating. However, the mechanism involved in mate choice does not seem to be as straightforward as in other similar systems of sympatric stickleback morphs and may involve variation in nest type.
Optimization using surrogate models and partially converged computational fluid dynamics simulations
Authors: Forrester Alexander I.J , Bressloff Neil W , Keane Andy J
Published: March 2006

Efficient methods for global aerodynamic optimization using computational fluid dynamics simulations should aim to reduce both the time taken to evaluate design concepts and the number of evaluations needed for optimization. This paper investigates methods for improving such efficiency through the use of partially converged computational fluid dynamics results. These allow surrogate models to be built in a fraction of the time required for models based on converged results. The proposed optimization methodologies increase the speed of convergence to a global optimum while the computer resources expended in areas of poor designs are reduced. A strategy which combines a global approximation built using partially converged simulations with expected improvement updates of converged simulations is shown to outperform a traditional surrogate-based optimization.