bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerosity Judgments for Tactile Stimuli Distributed over the Body Surface
Authors: Gallace Alberto , Tan Hong Z , Spence Charles
Published: February 2006

A large body of research now supports the claim that two different and dissociable processes are involved in making numerosity judgments regarding visual stimuli: subitising (fast and nearly errorless) for up to 4 stimuli, and counting (slow and error-prone) when more than 4 stimuli are presented. We studied tactile numerosity judgments for combinations of 1–7 vibrotactile stimuli presented simultaneously over the body surface. In experiment 1, the stimuli were presented once, while in experiment 2 conditions of single presentation and repeated presentation of the stimulus were compared. Neither experiment provided any evidence for a discontinuity in the slope of either the RT or error data suggesting that subitisation does not occur for tactile stimuli. By systematically varying the intensity of the vibrotactile stimuli in experiment 3, we were able to demonstrate that participants were not simply using the ‘global intensity’ of the whole tactile display to make their tactile numerosity judgments, but were, instead, using information concerning the number of tactors activated. The results of the three experiments reported here are discussed in relation to current theories of counting and subitising, and potential implications for the design of tactile user interfaces are highlighted.
Plaid Motion Rivalry: Correlates with Binocular Rivalry and Positive Mood State
Authors: Sheppard Bonita M , Pettigrew John D
Published: February 2006

Recently Hupé and Rubin (2003, Vision Research43 531–548) re-introduced the plaid as a form of perceptual rivalry by using two sets of drifting gratings behind a circular aperture to produce quasi-regular perceptual alternations between a coherent moving plaid of diamond-shaped intersections and the two sets of component ‘sliding’ gratings. We call this phenomenon plaid motion rivalry (PMR), and have compared its temporal dynamics with those of binocular rivalry in a sample of subjects covering a wide range of perceptual alternation rates. In support of the proposal that all rivalries may be mediated by a common switching mechanism, we found a high correlation between alternation rates induced by PMR and binocular rivalry. In keeping with a link discovered between the phase of rivalry and mood, we also found a link between PMR and an individual's mood state that is consistent with suggestions that each opposing phase of rivalry is associated with one or the other hemisphere, with the ‘diamonds’ phase of PMR linked with the ‘positive’ left hemisphere.
Corrigendum to: Genetic mapping of basal root gravitropism and phosphorus acquisition efficiency in common bean
Authors: Liao Hong , Yan Xiaolong , Rubio Gerardo , Beebe Steve E. , Blair Matthew W. , Lynch Jonathan P.
Published: February 2006

Root gravitropism determines the relative distribution of plant roots in different soil layers, and therefore, may influence the acquisition of shallow soil resources such as phosphorus (P). Growth pouch and field studies were conducted to evaluate root gravitropism of common bean (Phaseolus vulgaris L.) in response to P deficiency and to detect quantitative trait loci (QTL) associated with this trait. A deep-rooted genotype, DOR364, was crossed with a shallow-rooted genotype, G19833, to obtain 86 F5.7 recombinant inbred lines (RILs). Root gravitropic traits were measured as basal root growth angle (BRGA), shallow basal root length (SBRL, basal root length in the top 0-3 cm of soil) and relative shallow basal root length (RSBRL, percentage of basal root length in the top 0-3 cm of soil relative to total basal root length). Large genetic variability for these traits was found in the parents and RILs, with BRGA ranging from -18.73 to 56.69� and SBRL ranging from 0.42 to 2.63 m per plant. The parents and six RILs with contrasting root gravitropism were further evaluated in the field, where root shallowness was significantly correlated with plant growth and P uptake. QTL were detected by single point analysis (SPA), interval mapping (IM) and composite interval mapping (CIM) techniques with a genetic map for the DOR364 � G19833 population consisting of 236 molecular markers. The IM�/�CIM QTL were detected among the 11 linkage groups of common bean, with 16 QTL controlling the above root traits and six QTL controlling P acquisition efficiency (PAE) in the field study. At least three of the root trait QTL were associated with QTL for PAE, suggesting that root gravitropic traits are associated with PAE and that QTL for these traits can be used to facilitate selection and breeding for higher P efficiency in common bean and other crops.
Effects of Eupatorium yellow vein virus infection on photosynthetic rate, chlorophyll content and chloroplast structure in leaves of Eupatorium makinoi during leaf development
Authors: Funayama-Noguchi Sachiko , Terashima Ichiro
Published: February 2006

Infection of Eupatorium yellow vein geminivirus (EpYVV, formerly called tobacco leaf curl virus, TLCV) causes variegation in Eupatorium makinoi Kawahara et Yahara leaves. We examined changes in photosynthesis during leaf development to clarify what is the primary event when photosynthesis is suppressed in virus-infected E. makinoi leaves. The gas-exchange rate, leaf absorptance, chlorophyll (Chl) and nitrogen contents, leaf anatomy and chloroplast ultrastructure were compared between virus-infected and uninfected E. makinoi leaves at various developmental stages. These photosynthetic properties did not differ between infected and uninfected leaves when they were young. However, when expanded, infected leaves showed lower maximum quantum yield of photosynthetic CO2 uptake in the incident photosynthetically active photon fluence rate (PPFR), which was attributed to their lower Chl contents. The Chla / b ratio was higher and the grana had fewer thylakoids in the infected leaves, which are features common to Chl b-deficient mutants that have defects in Chl synthesis. Our results suggested that, in E. makinoi leaves, EpYVV infection primarily impairs Chl biosynthesis. Possible mechanisms of the suppression of photosynthesis in E. makinoi leaves by virus infection are discussed.
Comparison of real-time polymerase chain reaction and end-point polymerase chain reaction for the analysis of gene expression in preimplantation embryos
Authors: Gál Árpád Baji , Carnwath Joseph Wallace , Dinnyes Andras , Herrmann Doris , Niemann Heiner , Wrenzycki Christine
Published: February 2006

The aim of the present study was to compare real-time polymerase chain reaction (PCR) and end-point PCR with respect to their suitability for the analysis of gene expression in samples in which the number of cells is limited; for example, in studies of preimplantation embryonic development and to determine the variability of the real-time reverse transcription–PCR assay. The sensitivity, dynamic range and precision of both PCR systems were compared using a single mouse liver cDNA standard. The real-time system was 100-fold more sensitive than the end-point system and had a dynamic range of more than four orders of magnitude. The linear range for end-point PCR extended for two orders of magnitude using a fixed end-point of 31 cycles. The percentage standard error of the mean based on 30 replicates was 0.14% of the threshold cycle (Ct) value for the real-time system and 6.8% for the end-point fluorescence intensity. The coefficients of variation (CV) for reverse transcription combined with real-time analysis and the complete gene expression protocol consisting of mRNA isolation, reverse transcription and real-time PCR analysis were 0.6% and 1.4% of the Ct values, respectively. The present paper details, for the first time, measurement of the biological variation of individual mammalian oocytes. The CV was 1.8% of the Ct value for expression analysis of six bovine oocytes. The results are discussed in relation to the analysis of gene expression in preimplantation embryo development.
Regulation of expression of the retinoic acid-synthesising enzymes retinaldehyde dehydrogenases in the uteri of ovariectomised mice after treatment with oestrogen, gestagen and their combination
Authors: Rühl Ralph , Fritzsche Britta , Vermot Julien , Niederreither Karen , Neumann Ulrike , Schmidt Anja , Schweigert Florian J. , Dollé Pascal
Published: February 2006

The active metabolite of vitamin A, retinoic acid (RA), plays an important role in the female reproductive system. The synthesis of RA is tightly regulated by the activity of retinaldehyde dehydrogenases (Raldh). Among these, Raldh1 and Raldh2 exhibit specific temporal and spatial expression patterns in the mouse uterus, both during the oestrous cycle and early pregnancy. In the present study, we have assessed whether oestradiol and progesterone directly influence the uterine expression of Raldh1 and Raldh2 in ovariectomised mice. We investigated the effect of gestagen (promegestone 0.3 mg kg−1 bodyweight), oestrogen (oestradiol 3 µg kg−1 bodyweight) and their combination on the uterine expression of Raldh2. Expression was analysed using in situ hybridisation and quantified using real-time detection reverse transcription–polymerase chain reaction. The results show that the expression of Raldh2 is rapidly (within 1–4 h) induced in stromal cells by oestrogen, but not by gestagen, treatment, whereas combined oestrogen + gestagen treatment leads to a more prolonged (48 h) response. In contrast, oestrogen, but not progesterone, treatment downregulates (within 4–24 h) Raldh1 expression in the uterine glandular epithelium. We conclude that the uterine RA concentrations are regulated by oestrogens via an effect on the expression of the Raldh synthesising enzymes. Such a regulation is consistent with the natural fluctuations of Raldh expression during the oestrous cycle, early pregnancy and blastocyst implantation.
Overnourishing pregnant adolescent ewes preserves perirenal fat deposition in their growth-restricted fetuses
Authors: Matsuzaki Masatoshi , Milne John S. , Aitken Raymond P. , Wallace Jacqueline M.
Published: February 2006

Overnourishing the adolescent sheep promotes rapid maternal growth at the expense of the gravid uterus. The growth of the placenta is impaired and results in the premature delivery of low-birthweight lambs. The present study details fetal adipose tissue development in these growth-restricted pregnancies. Singleton pregnancies were established by embryo transfer and, thereafter, adolescent ewes were offered a high (H; n = 12) or moderate (M; n = 14) level of a complete diet until necropsy on Day 131 of gestation. Fetal weight was lower (P < 0.001) in H compared with M groups. High maternal intake preserved brain and perirenal fat weight (P < 0.003), whereas relative weights of the heart, lungs, spleen and liver were unaltered. High nutrient intake resulted in significantly elevated maternal plasma concentrations of insulin, leptin, prolactin and glucose, no significant changes in fetal insulin, leptin or non-esterified fatty acids and attenuated fetal prolactin concentrations. Irrespective of nutritional intake, maternal plasma leptin, prolactin and glucose concentrations were negatively correlated with fetal weight and were positively correlated with fetal perirenal fat proportion (all P < 0.01). The mRNA expression for leptin, prolactin receptor and uncoupling protein (UCP) 1 in fetal perirenal fat was equivalent between groups, but, irrespective of maternal nutrition, UCP1 mRNA levels were negatively correlated with fetal weight (P < 0.01). Thus, overnourishing pregnant adolescent sheep preserves fat deposition in their growth-restricted fetuses, which may have implications for neonatal thermogenesis and for programming of postnatal adiposity.
Assessment of basic seminal characteristics, sperm cryopreservation and heterologous in vitro fertilisation in the fishing cat (Prionailurus viverrinus)
Authors: Thiangtum Khongsak , Swanson William F. , Howard JoGayle , Tunwattana Wanchai , Tongthainan Dakara , Wichasilpa Wisid , Patumrattanathan Pornchai , Pinyopoommintr Tanu
Published: February 2006

Conservation of the fishing cat, a threatened south-east Asian felid, could benefit from effective ex situ genetic management and breeding programmes, including the use of assisted reproduction. The aims of the present study were to: (1) characterise basal seminal traits of fishing cats in Thailand zoos; and (2) investigate the effect of cryopreservation on sperm motility, acrosomal integrity and in vitro function. Seminal traits were evaluated in electroejaculates collected from eight males. Spermatozoa were diluted in n-tris(hydroxymethyl)-methyl-2-aminoethanesulfonic acid Tris (TEST)-yolk buffer (TYB) without glycerol, then diluted further with TYB with glycerol (4% final concentration) at either 25°C or after slow cooling to 5°C and frozen in straws over liquid nitrogen vapour. After thawing, sperm function was assessed by insemination of viable domestic cat oocytes. Fishing cat ejaculates averaged (± s.e.m.) 43.6 ± 14.2 × 106 motile spermatozoa with 33.5 ± 6.8% normal sperm morphology. Semen processing had a negligible effect (P > 0.05) on sperm motility and acrosomal integrity, but values were reduced (P < 0.05) after thawing. All thawed samples fertilised domestic cat oocytes, with 62.1% (36/58) of mature oocytes cleaving. Glycerol addition at 5°C resulted in higher (P < 0.05) post-thaw motility and intact acrosomes than glycerol addition at 25°C. In conclusion, good-quality ejaculates can be obtained from Thai fishing cats and their spermatozoa exhibit adequate function after cryopreservation for in vitro fertilisation procedures.
Effects of milrinone and butyrolactone-I on porcine oocyte meiotic progression and developmental competence
Authors: Grupen Christopher G. , Fung Maggie , Armstrong David T.
Published: February 2006

Inappropriate coordination of oocyte nuclear and cytoplasmic maturation is thought to contribute to the poor efficiency of embryo production in vitro. With the aim of improving this coordination, the effects of milrinone, an inhibitor of type 3 phosphodiesterases, and butyrolactone-I, a selective inhibitor of cdc2 kinases, on porcine oocyte maturation were investigated. Oocytes recovered from slaughterhouse-derived ovaries of prepubertal animals were treated with the inhibitors for 24 h. At concentrations of 50 and 250 μm, milrinone reversibly inhibited meiotic progression in 57% and 71% of oocytes, respectively. The presence or absence of milrinone in the medium used to wash oocytes for 30 min did not alter the inhibitory effect of the 24 h treatment. At concentrations of 25 and 50 μm, butyrolactone-I inhibited meiotic progression in 61% and 66% of oocytes, respectively, but the effect was not fully reversible in the absence of follicle-stimulating hormone (FSH). The presence of FSH during the butyrolactone-I treatment period increased the ability of oocytes to subsequently complete meiosis at 44 h without changing the inhibitory effect at 24 h. Following in vitro fertilisation at 44 and 50 h, treatment with butyrolactone-I and milrinone, alone or in combination, did not alter embryo cleavage rate, blastocyst formation rate or blastocyst cell number. Despite the different actions of milrinone and butyrolactone-I, the present study demonstrates that these reagents inhibit meiotic progression to a similar extent in the presence of FSH while maintaining developmental competence in porcine oocytes.
Visual method for evaluating the state of sexual development in male grey squirrels (Sciurus carolinensis)
Authors: Ferryman Mark , Mayle Brenda A. , Morgan Geoff W.
Published: February 2006

Stages of sexual development in grey squirrels were classified by scoring the presence of periscrotal hair and staining, as well as the position, size and colour of testes, to develop a visual breeding score (VBS). The VBS was a highly significant predictor of the presence and concentration of epididymal spermatozoa, which were produced from 12 months of age. Two classes of producers were identified: ‘high’ with spermatozoa levels >10 × 106 mL−1 and ‘low’ with spermatozoa levels <10 × 106 mL−1. Sperm motility was variable across all levels of productive males but was generally higher in the ‘high’ group, indicating that these were ‘functional’ males. Sexual regression was observed in two autumn periods. The VBS was less effective in determining states of regression and redevelopment; the confidence of classification improved when age class (adult or prepubertal) and date of capture was known. The use of the VBS to classify stages of sexual development in grey squirrels will improve selection of animals for studies of population biology and fertility control, and has potential application in captive breeding studies of rare Sciuridae species.
Links between α-catenin, NF-κB, and squamous cell carcinoma in skin
Authors: Kobielak Agnieszka , Fuchs Elaine
Published: February 2006

Cancers display a diverse set of cellular defects, which are thought to be elicited by multiple genetic mutations. In this study, we show that when a single adherens junction protein, α-catenin, is removed by conditional targeting, the entire skin epidermis systematically transforms to a hyperproliferative, invasive tissue replete with inflammation. Transcriptional profiling and biochemical analyses reveal that α-catenin ablation is accompanied by activation of NF-κB and its proinflammatory target genes, along with genes involved in proliferation, wound healing, angiogenesis, and metastasis. Many of these alterations occur
in vitro
and in the embryo, and thus seem at least partly to be intrinsic to the loss of α-catenin. We show that reductions in α-catenin, activation of NF-κB, and inflammation are common features of human squamous cell carcinomas of the skin.
Structural and function analyses of the global regulatory protein SarA from
Staphylococcus
aureus
Authors: Liu Yingfang , Manna Adhar C. , Pan Cheol-Ho , Kriksunov Irina A. , Thiel Daniel J. , Cheung Ambrose L. , Zhang Gongyi
Published: February 2006

The
sarA
locus in
Staphylococcus aureus
controls the expression of many virulence genes. The
sarA
regulatory molecule, SarA, is a 14.7-kDa protein (124 residues) that binds to the promoter region of target genes. Here we report the 2.6 Å-resolution x-ray crystal structure of the dimeric winged helix SarA protein, which differs from the published SarA structure dramatically. In the crystal packing, multiple dimers of SarA form a scaffold, possibly via divalent cations. Mutations of individual residues within the DNA-binding helix–turn–helix and the winged region as well as within the metal-binding pocket implicate basic residues R84 and R90 within the winged region to be critical in DNA binding, whereas acidic residues D88 and E89 (wing), D8 and E11 (metal-binding pocket), and cysteine 9 are essential for SarA function. These data suggest that the winged region of the winged helix protein participates in DNA binding and activation, whereas the putative divalent cation binding pocket is only involved in gene function.
Roles of the anaphase-promoting complex/cyclosome and of its activator Cdc20 in functional substrate binding
Authors: Eytan Esther , Moshe Yakir , Braunstein Ilana , Hershko Avram
Published: February 2006

The anaphase-promoting complex/cyclosome (APC/C) is a multisubunit ubiquitin-protein ligase that targets for degradation cell-cycle regulatory proteins during exit from mitosis and in the G
1
phase of the cell cycle. The activity of APC/C in mitosis and in G
1
requires interaction with the activator proteins Cdc20 and Cdh1, respectively. Substrates of APC/C–Cdc20 contain a recognition motif called the “destruction box” (D-box). The mode of the action of APC/C activators and their possible role in substrate binding remain poorly understood. Several investigators suggested that Cdc20 and Cdh1 mediate substrate recognition, whereas others proposed that substrates bind to APC/C or to APC/C–activator complexes. All these studies used binding assays, which do not necessarily indicate that substrate binding is functional and leads to product formation. In the present investigation we examined this problem by an “isotope-trapping” approach that directly demonstrates productive substrate binding. With this method we found that the simultaneous presence of both APC/C and Cdc20 is required for functional substrate binding. By contrast, with conventional binding assays we found that either Cdc20 or APC/C can bind substrate by itself, but only at low affinity and relaxed selectivity for D-box. Our results are consistent with models in which interaction of substrate with specific binding sites on both APC/C and Cdc20 is involved in selective and productive substrate binding.
Dicer
function is essential for lung epithelium morphogenesis
Authors: Harris Kelley S. , Zhang Zhen , McManus Michael T. , Harfe Brian D. , Sun Xin
Published: February 2006

DICER is a key enzyme that processes microRNA and small interfering RNA precursors into their short mature forms, enabling them to regulate gene expression. Only a single
Dicer
gene exists in the mouse genome, and it is broadly expressed in developing tissues.
Dicer
-null mutants die before gastrulation. Therefore, to study
Dicer
function in the later event of lung formation, we inactivated it in the mouse lung epithelium using a
Dicer
conditional allele and the

Sonic Hedgehog
cre

(

Shh
cre

) allele. Branching arrests in these mutant lungs, although epithelial growth continues in distal domains that are expanded compared with normal samples. These defects result in a few large epithelial pouches in the mutant lung instead of numerous fine branches present in a normal lung. Significantly, the initial phenotypes are apparent before an increase in epithelial cell death is observed, leading us to propose that
Dicer
plays a specific role in regulating lung epithelial morphogenesis independent of its requirement in cell survival. In addition, we found that the expression of
Fgf10
, a key gene involved in lung development, is up-regulated and expanded in the mesenchyme of
Dicer
mutant lungs. Previous studies support the hypothesis that precise localization of FGF10 in discrete sites of the lung mesenchyme serves as a chemoattractant for the outgrowth of epithelial branches. The aberrant
Fgf10
expression may contribute to the
Dicer
morphological defects. However, the mechanism by which DICER functions in the epithelium to influence
Fgf10
expression in the mesenchyme remains unknown.
The wild-derived inbred mouse strain SPRET/Ei is resistant to LPS and defective in IFN-β production
Authors: Mahieu Tina , Park Jin Mo , Revets Hilde , Pasche Bastian , Lengeling Andreas , Staelens Jan , Wullaert Andy , Vanlaere Ineke , Hochepied Tino , van Roy Frans , Karin Michael , Libert Claude
Published: February 2006

Although activation of Toll-like receptor 4 (TLR4)-positive cells is essential for eliminating Gram-negative bacteria, overactivation of these cells by the TLR4 ligand LPS initiates a systemic inflammatory reaction and shock. Here we demonstrate that SPRET/Ei mice, derived from
Mus spretus
, exhibit a dominant resistance against LPS-induced lethality. This resistance is mediated by bone marrow-derived cells. Macrophages from these mice exhibit normal signaling and gene expression responses that depend on the myeloid differentiation factor 88 adaptor protein, but they are impaired in IFN-β production. The defect appears to be specific for IFN-β, although the SPRET/Ei IFN-β promoter is normal.
In vivo
IFN-β induction by LPS or influenza virus is very low in SPRET/Ei mice, but IFN-β-treatment restores the sensitivity to LPS, and IFN type 1 receptor-deficient mice are also resistant to LPS. Because of the defective induction of IFN-β, these mice are completely resistant to
Listeria monocytogenes
and highly sensitive to
Leishmania major
infection. Stimulation of SPRET/Ei macrophages leads to rapid down-regulation of IFN type 1 receptor mRNA expression, which is reflected in poor induction of IFN-β-dependent genes. This finding indicates that the resistance of SPRET/Ei mice to LPS is due to disruption of a positive-feedback loop that amplifies IFN-β production. In contrast to TLR4-deficient mice, SPRET/Ei mice resist both LPS and sepsis induced with
Klebsiella pneumoniae
.
Structures of wild-type and mutant human spermidine/spermine
N
1
-acetyltransferase, a potential therapeutic drug target
Authors: Bewley Maria C. , Graziano Vito , Jiang Jiangsheng , Matz Eileen , Studier F. William , Pegg Anthony E. , Coleman Catherine S. , Flanagan John M.
Published: February 2006

Spermidine/spermine
N
1
-acetyltransferase (SSAT) is a key enzyme in the control of polyamine levels in human cells, as acetylation of spermidine and spermine triggers export or degradation. Increased intracellular polyamine levels accompany several types of cancers as well as other human diseases, and compounds that affect the expression, activity, or stability of SSAT are being explored as potential therapeutic drugs. We have expressed human SSAT from the cloned cDNA in
Escherichia coli
and have determined high-resolution structures of wild-type and mutant SSAT, as the free dimer and in binary and ternary complexes with CoA, acetyl-CoA (AcCoA), spermine, and the inhibitor
N
1
,
N
11
-bis-(ethyl)-norspermine (BE-3-3-3). These structures show details of binding sites for cofactor, substrates, and inhibitor and provide a framework to understand enzymatic activity, mutations, and the action of potential drugs. Two dimer conformations were observed: a symmetric form with two open surface channels capable of binding substrate or cofactor, and an asymmetric form in which only one of the surface channels appears capable of binding and acetylating polyamines. SSAT was found to self-acetylate lysine-26 in the presence of AcCoA and absence of substrate, a reaction apparently catalzyed by AcCoA bound in the second channel of the asymmetric dimer. These unexpected and intriguing complexities seem likely to have some as yet undefined role in regulating SSAT activity or stability as a part of polyamine homeostasis. Sequence signatures group SSAT with proteins that appear to have thialysine
N
ε
-acetyltransferase activity.
Cost Reduction With Successful Implementation of an Antibiotic Prophylaxis Program in a Private Hospital in Ribeirão Preto, Brazil
Authors: Fonseca Silvia N. Szente , Melon Kunzle Sônia R. , Silva Sheila A. Barbosa , Schmidt Jorge G. , Mele Roberto R.
Published: February 2006

Objective:

To describe the implementation and results of a perioperative antibiotic prophylaxis (PAP) program.

Design:

A protocol for correct use of PAP was implemented in December 1994. For selected months we measured the PAP protocol compliance of a random sample of clean and clean-contaminated procedures and calculated the cost of incorrect use of PAP.

Setting:

A 180-bed general hospital in Ribeirão Preto, Brazil.

Results:

The cost of unnecessary PAP in the obstetric and gynecologic, cardiothoracic, and orthopedic services dropped from $4,224.54 ($23.47/procedure) in November 1994 to $1,147.24 ($6.17/procedure, January 1995), $544.42 ($3.58/procedure, May 1995), $99.06 ($0.50/procedure, August 1995), and $30 ($0.12/procedure, March 1996). In November 1994, only 13.6% of all surgical procedures were done with correct use of PAP, compared to 59% in January 1995, 73% in August 1995, 78% in March 1996, 92% in November 1996, and 98% in May 1997.

Conclusions:

Incorrect PAP use wastes resources, which is a particular problem in developing countries. Our program is simple and can be implemented without the use of computers and now is being adopted in other hospitals in our region. We credit the success of our program to the commitment of all participants and to the strong support of the hospital directors.
Hepatitis B Vaccination of Personnel Employed in Victorian Hospitals: Are Those at Risk Adequately Protected?
Authors: Thompson Sandra C. , Norris Maureen
Published: February 2006

Objective:

To examine the policies and practices in hospitals within the state of Victoria, Australia, with respect to vaccination of staff against hepatitis B infection.

Design:

A written self-administered questionnaire to be completed by the infection control officer (or designated officer for hepatitis B vaccination) within each hospital.

Setting:

Public (teaching and nonteaching) and private hospitals, including metropolitan and rural institutions in Victoria.

Participants:

A random sample of 30% of Victorian hospitals were asked to participate in the survey. Of 78 eligible institutions, 69 (88%) completed and returned questionnaires.

Results:

There was no consistent hepatitis B prevention policy in place across Victoria. Of the 69 responding hospitals, 63 (91%) offered hepatitis B vaccination to staff, and 58 (84%) of these also paid all costs of vaccination. Of the 63 hospitals offering vaccination to staff, 39 offered vaccination to all staff, 23 offered vaccination based on job title, and one offered vaccination based on anticipated exposure. In many institutions, postexposure protocols were recalled more readily than preexposure vaccination guidelines. Numerous respondents indicated a need for clear guidelines on policy and clarification on practical matters of management, such as acceptable immune levels, management of nonresponders to the primary series, and the need for, and timing of, booster doses of vaccine. Eleven (18%) of the 63 hospitals offering hepatitis B vaccination to staff undertook routine prevaccination screening, a practice not generally regarded as cost-effective in Australia. Fifty-five of these hospitals (91%) also undertook postvaccination screening.

Conclusions:

It is evident from this study that a considerable number of potentially susceptible healthcare personnel in Victorian hospitals remain unprotected against hepatitis B infection. A more reliable and consistent approach to preexposure hepatitis B vaccination is recommended
Association Between Mucositis Severity and Vancomycin-Resistant Enterococcal Bloodstream Infection in Hospitalized Cancer Patients
Authors: Kuehnert Matthew J. , Jernigan John A. , Pullen Amy L. , Rimland David , Jarvis William R.
Published: February 2006

Objective:

To determine the role of mucositis severity in the development of vancomycin-resistant enterococcal (VRE) bloodstream infection (BSI).

Setting:

A tertiary-care university medical center.

Participants:

Hematology-oncology-unit inpatients.

Design:

Patients with VRE BSI (case-patients) were compared with VRE-colonized (control) patients from September 1994 through August 1997. Oral mucositis severity was recorded on the day of VRE BSI for case-patients and on hospital day 22 (median day of hospitalization of case-patient VRE BSI) for controls. There were 19 case-patients and 31 controls.

Results:

In univariate analysis, case-patients were significantly more likely than controls to have a higher mucositis severity score, diarrhea, or a higher severity of illness score. In multivariate analysis, only mucositis remained as an independent risk factor, and increasing mucositis score was significantly associated with VRE BSI.

Conclusions:

Mucositis severity was independently associated with an increasing risk for VRE BSI. Interventions to alter mucositis severity may help to prevent VRE BSI in hospitalized cancer patients.
Enteric Carriage of Vancomycin-ResistantEnterococcus faeciumin Patients Tested forClostridium difficile
Authors: Garbutt Jane M. , Littenberg Benjamin , Evanoff Bradley A. , Sahm Daniel , Mundy Linda M.
Published: February 2006

Objective:

To identify independent risk factors for enteric carriage of vancomycin-resistantEnterococcus faecium(VREF) in hospitalized patients tested forClostridium difficiletoxin.

Design:

Retrospective case-cohort study.

Setting:

Tertiary-care teaching hospital.

Patients:

Convenience sample of 215 adult inpatients who had stool tested forC difficilebetween January 29 and February 25,1996.

Results:

41 (19%) of 215 patients had enteric carriage of VREF. Five independent risk factors for enteric VREF were identified: history of priorC difficile(odds ratio [OR], 15.21; 95% confidence interval [CI95], 3.30-70.10;P<.001), parenteral treatment with vancomycin for ≥5 days (OR, 4.06; CI95, 1.54-10.73;P=.005), treatment with antimicrobials effective against gram-negative organisms (OR, 3.44; CI95, 1.20-9.87;P=.021), admission from another institution (OR, 2.95; CI95, 1.21-7.18;P=.017), and age >60 years (OR 2.57; CI95, 1.13-5.82;P=.024). These risk factors for enteric VREF were independent of the patient's currentC difficilestatus.

Conclusions:

Antimicrobial exposures are the most important modifiable independent risk factors for enteric carriage of VREF in hospitalized patients tested forC difficile.
Reporting of Vancomycin-Resistant Enterococci in Connecticut: Implementation and Validation of a State-Based Surveillance System
Authors: Dembek Zygmunt F. , Kellerman Scott E. , Ganley Lisa , Capacchione Constance M. , Tenover Fred C. , Cartter Matthew L. , Van Kruiningen Herbert J. , Jarvis William R. , Hadler James L.
Published: February 2006

Objective:

To assess state-based surveillance for isolation from a sterile site of vancomycin-resistant enterococci (VRE) in Connecticut.

Design:

Clinical laboratory reporting (passive surveillance) of VRE isolates to the Connecticut Department of Public Health (CDPH) was followed by state-initiated validation, laboratory proficiency testing, and review of hospital demographic characteristics.

Settings:

All 45 clinical laboratories and all 37 (36 for 1995 and 1996) acute-care hospitals in Connecticut were included in the study.

Main Outcome Measures:

The outcome measures included determination of the statewide incidence of VRE and the accuracy of passive reporting, determination of clinical laboratory proficiency in detecting VRE, and analysis of hospital characteristics that might be associated with an increased incidence of VRE.

Results:

During 1994 through 1996, 29 (78%) of 37 hospital-affiliated clinical laboratories and 1 (11%) of 9 commercial or other laboratories in Connecticut reported to the CDPH the isolation of VRE from sterile sites; 158 isolates were reported for these 3 years. Based on verification, we discovered that these laboratories actually detected 58 VRE isolates in 1994, 104 in 1995, and 104 in 1996 (total, 266). The age-standardized incidence rate of VRE was 14.1 cases per million population in 1994 and 26.8 cases per million population for both 1995 and 1996. Laboratory proficiency testing revealed that high-level vancomycin resistance was identified accurately and that low- and moderate-level resistance was not detected. The incidence of VRE isolates was three times greater in hospitals with over 300 beds compared with categories of hospitals with fewer beds. Increases in the number of VRE isolates were at least twice as likely in hospitals located in areas with a higher population density, or with a residency program or trauma center in the hospital.

Conclusions:

Passive reporting of VRE isolates from sterile sites markedly underestimated the actual number of isolates, as determined in a statewide reporting system. Statewide passive surveillance systems for routine or emerging pathogens must be validated and laboratory proficiency ensured if results are to be accurate and substantial underreporting is to be corrected.
Comparative in Vitro Activity of Antiseptics and Disinfectants Versus Clinical Isolates ofCandida Species
Authors: Silverman Jan , Vazquez Jose A. , Sobel Jack D. , Zervos Marcus J.
Published: February 2006

Objective:

To evaluate the in vitro activity of antiseptics and detergents againstCandida.

Design:

One strain each ofCandida albicans, Candida tropicalis, Candida lusitaniae, Candida parapsilosis, Candida kefyr, Candida glabrata,and an American Type Culture Collection strain ofEscherichia coli(control) were studied. Clinical isolates were obtained from patients in a bone marrow unit of a large tertiary hospital. Antiseptic and disinfectant agents studied were used in the hospital where isolates were identified for cleaning of inanimate surfaces or hand washing. In vitro susceptibility was determined using a broth macrodilution method with exposure times to antiseptic or disinfectant agent of 15 seconds to 4 minutes and concentrations of agents that ranged from undiluted to 1:10,000 dilution.

Setting:

A 900-bed teaching hospital.

Results:

Of disinfectants tested, Vestal and Sparquat inhibited growth of all species at dilutions of ≤1:100 at all contact times for all species. Clorox showed inhibition of growth at 1:100 dilution after 30 seconds of contact time for all isolates. Of antiseptics studied, Hibiclens inhibited growth of all species exceptC tropicalisat dilutions of ≤1:100 at all contact times and for Ctropicalisafter 60 seconds. Clinidine inhibited growth of all species at dilutions of ≤1:100 at all contact times for all species with the exception ofC glabrataandC tropicalis,which grew at the undiluted concentration. Ultradex failed to demonstrate killing of any species for any dilutions tested.

Conclusions:

The results of this study show varying degrees of in vitro inhibition of growth by a variety of antiseptics and disinfectants against clinical isolates ofCandidaspecies from hospitalized patients.
Undetected Vancomycin-Resistant Enterococcus in Surgical Intensive Care Unit Patients
Authors: Zuckerman Richard A. , Steele Lynn , Venezia Richard A. , Tobin Ellis H.
Published: February 2006

The rates of vancomycin-resistant Enterococcus (VRE) in a high-risk population were investigated prospectively using an active surveillance method. The costs of conducting active surveillance were calculated. Among the 10 patients found to have VRE, routine cultures identified 3 (30%); thus, 70% of the VRE-colonized patients would have gone undetected in the absence of active surveillance. The total cost for 5 weeks of active surveillance was $2,234. Although active surveillance identified a high rate of VRE-colonized patients who otherwise may not have been identified, it remains to be determined if the additional costs are justified and result in reduced transmission.
Recovery of High-Level Streptomycin-Resistant Enterococci From Hemodialysis Water and Dialysate in 85 Greek Renal Units
Authors: Arvanitidou Malamatenia , Vayona Argiri , Pigadas Alkis , Tsakris Athanassios
Published: February 2006

In the 85 renal units of Greece, enterococci were recovered from 10 samples of tap water, 6 of treated hemodialysis water, and 21 of dialysate. Eleven isolates wereEnterococcus faecium,and 8 wereEnterococcus raffinosus;6 other additional enterococcal species were found. Twenty-two strains exhibited high-level resistance to streptomycin, 16 were resistant to rifampicin, and one to erythromycin. In our hemodialysis units, treated water and dialysate raise concern regarding transfer to patients of uncommon enterococcal species exhibiting high-level streptomycin resistance.
Methicillin-ResistantStaphylococcus aureusin the Community: A Hospital-Based Study
Authors: Goetz Angella , Posey Kathy , Fleming Jean , Jacobs Sharon , Boody Linda , Wagener Marilyn M. , Muder Robert R.
Published: February 2006

To determine the proportion of methicillin-resistantStaphylococcus aureus(MRSA) among patients presenting for hospitalization and to assess risk factors for MRSA carriage, we conducted a study for 13 months at five Pittsburgh-area hospitals. Of 504S aureusidentified, 125 (25%) were MRSA Independent risk factors for MRSA included organ transplantation, employment in a healthcare facility, pressure sores, tube feeding, and hospitalization within the preceding year.
Do Influenza Epidemics Affect Patterns of Sickness Absence Among British Hospital Staff?
Authors: Nguyen-Van-Tam Jonathan , Granfield Ruth , Pearson James , Fleming Douglas , Keating Nicola
Published: February 2006

Influenza vaccination for healthcare workers is not recommended in Britain, but some hospitals offer vaccine to reduce sickness absence. However, in Nottingham, the influenza epidemics of 1993-94 and 1996-97 made no impact on staff absence. Annual vaccination of healthcare workers against influenza is unlikely to reduce absence most winters, but there may be gains in terms of preventing nosocomial infection.
Who Is at Risk of What?
Authors: Birnbaum David
Published: February 2006

If you have calculated the sample size required for an employee survey or an observational study of departmental practices but found that the number of observations required is larger than the number of employees, chances are the error is due to use of approximation formulae. Many of us unknowingly were taught to use approximations that fail to include the finite population correction factor. Depending on the objective of a study and the proportion of a population sampled, it may be necessary to consider this correction factor in order to estimate standard error and sample size accurately.
An Outbreak of Hospital-Acquired Hepatitis B Virus Infection Among Patients Receiving Chronic Hemodialysis
Authors: Hutin Yvan J.E , Goldstein Susan T. , Varma Jay K. , O'Dair Joan B. , Mast Eric E. , Shapiro Craig N. , Alter Miriam J.
Published: February 2006

Objective:

To investigate a cluster of hepatitis B virus (HBV) infections between December 1995 and May 1996 among chronic hemodialysis patients in one county.

Setting:

Two dialysis centers (A and B) and a hospital (C) in one county.

Patients:

Six case-patients who were dialyzed in one of two centers, A and B, and had all been hospitalized between January and February 1996 at hospital C.

Methods:

Patient 1, usually dialyzed in center A sero-converted to hepatitis B surface antigen (HBsAg) in December 1995 and could have been the source of infection for the others, who seroconverted between March and April 1996. Two cohort studies were conducted: one among patients dialyzed in center A to determine where transmission had occurred, and one among patients dialyzed at hospital C at the time patient 1 was hospitalized, to identify factors associated with infection.

Results:

Four (15%) of the 26 susceptible patients dialyzed at center A became infected with HBV. Hospitalization at hospital C when patient 1 was hospitalized was associated with infection (P=.002). A cohort study of the 10 susceptible patients dialyzed at hospital C during the time patient 1 was hospitalized did not identify specific risk factors for infection. However, supplies and multidose vials were shared routinely among patients, providing opportunities for transmission.

Conclusion:

When chronic hemodialysis patients require dialysis while hospitalized, their HBsAg status should be reviewed, and no instrument, supplies, or medications should be shared among them.
Safety of Peripheral Intravenous Catheters in Children
Authors: Shimandle Ruth B. , Johnson Daniel , Baker Mark , Stotland Naomi , Karrison Theodore , Arnow Paul M.
Published: February 2006

Objectives:

To determine the overall and per-day risk of complications of short peripheral intravenous (PIV) catheters placed for indefinite periods.

Design:

During 5 months, general pediatric patients receiving intravenous therapy through short PIV catheters were monitored. Patient and catheter characteristics were recorded, complications were noted, and rolled semiquantitative cultures of removed catheters were performed. Major endpoints were infection and phlebitis. Per-day risk of complications and catheter colonization (>15 colony-forming units) were calculated.

Setting:

University children's hospital.

Patients:

General pediatric ward inpatients with PIV.

Results:

We studied 642 Teflon catheters in place >24 hours (mean, 3.7 days) in 525 patients. There were no cases of catheter sepsis (0%; 95% confidence interval [CI95], 0%-0.6%), one possible insertion-site infection (0.2%; CI95, 0.004%-0.9%), and seven cases of phlebitis (1.1%; CI95, 0.4%-2.3%). Catheter colonization occurred in 92 (26%) of 348 catheters cultured. Neither the per-day risk of phlebitis nor of catheter colonization increased significantly with placement >3 days.

Conclusion:

Current guidelines recommend replacement of PIV catheters in adults within 2 to 3 days; no recommendations are made for children. Our findings and those of others indicate that the overall risk of PIV catheter complications in children is extremely low and would not be reduced substantially by routine catheter replacement.
“Pulse” Nasal Mupirocin Maintenance Regimen in Patients Undergoing Continuous Ambulatory Peritoneal Dialysis
Authors: Mylotte Joseph M. , Kahler Lucinda , Jackson Ellen
Published: February 2006

Objective:

To determine, among patients undergoing continuous ambulatory peritoneal dialysis (CAPD) who wereStaphylococcus aureusnasal carriers, if periodic brief “pulses” of nasal mupirocin calcium ointment 2% after completion of a mupirocin eradication protocol would maintain these patients free of carriage.

Design:

Noncomparative, nonblinded study with historical controls.

Setting:

A county medical center.

Patients:

Patients in a CAPD program during the period April 1996 to May 1998.

Methods:

All patients in the CAPD program had monthly nasal cultures forS aureus. After informed consent,S aureusnasal carriers were administered mupirocin to the nares twice a day for 5 days followed by nasal mupirocin twice monthly. Peritonitis and exit-site infection rates were monitored independently by CAPD nursing staff. Patients were monitored monthly for adverse effects of mupirocin and compliance with the maintenance regimen.

Results:

Twenty-four patients in the CAPD program were enrolled in the study and had a median duration of follow-up of 8.5 months. Fifteen (63%) of the 24 patients remained free of nasal carriage on follow-up cultures. Of the 9 patients with positive nasal cultures during the study, 8 had only one positive culture. There was no significant difference in the mean yearly peritonitis rate orS aureusperitonitis rate (January 1995-May 1998). However, there was a significant decrease in the mean yearly exit-site infection rates both overall (from 8.8 episodes per 100 patients dialyzed per month in 1995 to 4.0 in 1998;P=.008) and due toS aureus(from 5.6 in 1995 to 0.9 in 1998;P=.03). Adverse effects of nasal mupirocin were mild overall; 1 patient was removed from the study due to an allergic reaction to mupirocin.

Conclusions:

Among CAPD patients who wereS aureusnasal carriers, periodic brief treatment with nasal mupirocin after an initial eradication regimen kept them free of carriage, for the most part, with few adverse effects. The pulse mupirocin regimen offers simplicity and possibly better compliance, as well as minimizing exposure to this agent, thereby possibly reducing the risk of resistance. Further studies are warranted to compare this regimen to other commonly used mupirocin maintenance regimens in dialysis patients.