bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidemiology and Typing of
Staphylococcus aureus
Strains Isolated from Bloodstream Infections
Authors: van der Mee-Marquet Nathalie , Domelier Anne-Sophie , Girard Nicole , Quentin Roland ,   the Bloodstream Infection Study Group of the Relais d'Hygiène du Centre
Published: December 2004

We carried out an epidemiological study covering 2,365,067 patient days of hospitalization between 2000 and 2003. During this time, 413
Staphylococcus aureus
bloodstream infections occurred. This corresponds to 15% of the 2,676 bloodstream infections observed during this period in the 31 hospitals in our region of France, which has 2.5 million inhabitants. The incidence of nosocomial
S. aureus
bloodstream infections was 0.11 per 1,000 days of hospitalization. The prevalence of methicillin-resistant
S. aureus
(MRSA) strains, of which 13% were nonmultiresistant MRSA (NORSA), was 33%, and this percentage was stable over the 4 years. In contrast, the prevalence of
S. aureus
strains susceptible to methicillin but resistant to quinolones or susceptible to methicillin but multiresistant to antibiotics (EMSSA strains) increased from 4% in 2000 to 23% in 2003. As previously reported, MRSA strains were mostly recovered from nosocomial bloodstream infections, whereas NORSA strains—generally considered to be responsible for community-acquired infections—were always isolated from nosocomial bloodstream infections. Pulsed-field gel electrophoresis (PFGE) analysis of 109 MRSA strains and 15 EMSSA strains demonstrated clonal diffusion of the three major French MRSA clones and revealed considerable genetic heterogeneity among EMSSA strains. Although no epidemiologically related NORSA strains clustered in particular PFGE groups, the distribution of MRSA strains isolated from bloodstream infections according to the portal of entry (vascular devices, pulmonary, and urinary) was not random for the major PFGE clones, suggesting that each MRSA lineage displays particular virulence features.
Multiplex PCR Targetingtpi(Triose Phosphate Isomerase),tcdA(Toxin A), andtcdB(Toxin B) Genes for Toxigenic Culture ofClostridium difficile
Authors: Lemee Ludovic , Dhalluin Anne , Testelin Sabrina , Mattrat Marie-Andre , Maillard Karine , Lemeland Jean-François , Pons Jean-Louis
Published: December 2004

A multiplex PCR toxigenic culture approach was designed for simultaneous identification and toxigenic type characterization ofClostridium difficileisolates. Three pairs of primers were designed for the amplification of (i) a species-specific internal fragment of thetpi(triose phosphate isomerase) gene, (ii) an internal fragment of thetcdB(toxin B) gene, and (iii) an internal fragment of thetcdA(toxin A) gene allowing distinction between toxin A-positive, toxin B-positive (A+B+) strains and toxin A-negative, toxin B-positive (A−B+) variant strains. The reliability of the multiplex PCR was established by using a panel of 72C. difficilestrains including A+B+, A−B−, and A−B+ toxigenic types and 11 otherClostridiumspecies type strains. The multiplex PCR assay was then included in a toxigenic culture approach for the detection, identification, and toxigenic type characterization ofC. difficilein 1,343 consecutive human and animal stool samples. Overall, 111 (15.4%) of 721 human samples were positive forC. difficile; 67 (60.4%) of these samples contained A+B+ toxigenic isolates, and none of them contained A−B+ variant strains. Fifty (8%) of 622 animal samples containedC. difficilestrains, which were toxigenic in 27 (54%) cases, including 1 A−B+ variant isolate. Eighty of the 721 human stool samples (37 positive and 43 negative forC. difficileculture) were comparatively tested by Premier Toxins A&B (Meridian Bioscience) and TriageC. difficilePanel (Biosite) immunoassays, the results of which were found concordant with toxigenic culture for 82.5 and 92.5% of the samples, respectively. The multiplex PCR toxigenic culture scheme described here allows combined diagnosis and toxigenic type characterization for human and animalC. difficileintestinal infections.
Use of Highly Variable Intergenic Spacer Sequences for Multispacer Typing ofRickettsia conoriiStrains
Authors: Fournier Pierre-Edouard , Zhu Yong , Ogata Hiroyuki , Raoult Didier
Published: December 2004

By use of the nearly perfectly colinear genomes ofRickettsia conoriiandRickettsia prowazekii, we compared the usefulness of three types of sequences for typing ofR. conoriiisolates: (i) 5 variable coding genes comprising the 16S ribosomal DNA,gltA,ompB, andsca4(gene D) genes, which are present in both genomes, and theompAgene, which is degraded inR. prowazekii; (ii) 28 genes degraded inR. conoriibut intact inR. prowazekii, including 23 split and 5 remnant genes; and (iii) 27 conserved and 25 variable intergenic spacers. The 4 conserved and 23 split genes as well as the 27 conserved intergenic spacers each had identical sequences in 34 human and 5 tick isolates ofR. conorii. Analysis of theompAsequences identified three genotypes ofR. conorii. The variable intergenic spacers were significantly more variable than conserved genes, split genes, remnant genes, and conserved spacers (P< 10−2in all cases). Four of the variable intergenic spacers (dksA-xerC,mppA-purC,rpmE-tRNAfMet, and tRNAGly-tRNATyr) had highly variable sequences; when they were combined for typing, multispacer typing (MST) identified 27 different genotypes in the 39R. conoriiisolates. Two batches from the sameR. conoriistrain, Malish (Seven), with different culture passage histories were found to exhibit the same MST type. MST was more discriminatory for strain genotyping than multiple gene sequencing (P< 10−2). Phylogenetic analysis based on MST sequences was concordant with the geographic origins ofR. conoriiisolates. Our study supports the usefulness of MST for strain genotyping. This tool may be useful for tracing a strain and identifying its source during outbreaks, including those resulting from bioterrorism.
Surface Immunoglobulin-Deficient Epstein-Barr Virus-Infected B Cells in the Peripheral Blood of Pediatric Solid-Organ Transplant Recipients
Authors: Schauer Elizabeth , Webber Steven , Green Michael , Rowe David
Published: December 2004

Epstein-Barr virus (EBV), a ubiquitous human herpesvirus, normally causes an asymptomatic latent infection with very low levels of circulating virus in the peripheral blood of infected individuals. However, EBV does have pathogenic potential and has been linked to several diseases, including posttransplant lymphoproliferative disease (PTLD), which involves very high circulating viral loads. As a consequence of immunosuppression associated with transplantation, children in particular are at risk for PTLD. Even in the absence of symptoms of PTLD, very high viral loads are often observed in these patients. EBV-infected B cells in the circulations of 16 asymptomatic pediatric solid-organ transplant recipients from Children's Hospital of Pittsburgh were simultaneously characterized for their surface immunoglobulin (sIg) isotypes and EBV genome copy numbers. Patients were characterized as having high and low viral loads on the basis of their stable levels of circulating virus. Patients with high viral loads had both high- and low-copy-number cells. Cells with a high numbers of viral episomes (>20/cell) were predominantly Ig null, and cells with low numbers of episomes were predominantly sIgM positive. Patients with low viral loads carried the vast majority of their viral load in low-copy-number cells, which were predominantly IgM positive. The very rare high-copy-number cells detected in carriers with low viral loads were also predominantly Ig-null cells. This suggests that two distinct types of B-lineage cells contribute to the viral load in transplant recipients, with cells bearing high genome copy numbers having an aberrant Ig-null cellular phenotype.
Diverse CTX Phages among Toxigenic
Vibrio cholerae
O1 and O139 Strains Isolated between 1994 and 2002 in an Area Where Cholera is Endemic in Bangladesh
Authors: Nusrin Suraia , Khan G. Yeahia , Bhuiyan N. A. , Ansaruzzaman M. , Hossain M. A. , Safa Ashrafus , Khan Rasel , Faruque Shah M. , Sack David A. , Hamabata T. , Takeda Yoshifumi , Nair G. Balakrish
Published: December 2004

PCR surveillance of the
rstR
genes of CTX phages in
Vibrio cholerae
O1 and O139 showed no relationship between the incidence of disease and changes in the
rstR
but showed variations in their presence in O1 and O139 strains and the occurrence of multiple types in a few strains.
Rapid Discrimination between Human Immunodeficiency Virus Type 2 Groups A and B by Real-Time PCR
Authors: Plantier Jean-Christophe , Gueudin Marie , de Oliveira Fabienne , Damond Florence , Lemée Véronique , Brun-Vézinet Françoise , Simon François
Published: December 2004

We studied the feasibility of genotyping human immunodeficiency virus (HIV) type 2 groups A and B by real-time PCR. Two group-specific PCRs were developed. Real-time genotyping of 22 samples of genotype A, 10 samples of genotype B, and the isolate of new group H were compared to genotyping by sequencing and phylogeny. The group-specific PCRs specifically identified 84.3% of group A or B samples; isolate H was not detected. This method allowed rapid and specific discrimination between HIV-2 groups A and B and could be a useful tool for molecular epidemiological studies.
Comparison of Five Methods for Extraction of
Legionella pneumophila
from Respiratory Specimens
Authors: Wilson Deborah , Yen-Lieberman Belinda , Reischl Udo , Warshawsky Ilka , Procop Gary W.
Published: December 2004

The efficiencies of five commercially available nucleic acid extraction methods were evaluated for the recovery of a standardized inoculum of
Legionella pneumophila
in respiratory specimens (sputum and bronchoalveolar lavage [BAL] specimens). The concentrations of
Legionella
DNA recovered from sputa with the automated MagNA Pure (526,200 CFU/ml) and NucliSens (171,800 CFU/ml) extractors were greater than those recovered with the manual methods (i.e., Roche High Pure kit [133,900 CFU/ml], QIAamp DNA Mini kit [46,380 CFU/ml], and ViralXpress kit [13,635 CFU/ml]). The rank order was the same for extracts from BAL specimens, except that for this specimen type the QIAamp DNA Mini kit recovered more than the Roche High Pure kit.
Clinical Evaluation of the Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test for Rapid Diagnosis of Tuberculosis Lymphadenitis
Authors: Kerleguer A. , Fabre M. , Bernatas J. J. , Gerome P. , Nicand E. , Herve V. , Koeck J. L.
Published: December 2004

This prospective study evaluated the performance of the Amplified Mycobacterium Tuberculosis Direct Test (MTD) for the diagnosis of lymph node tuberculosis in Djibouti, Republic of Djibouti. Of 197 specimens sampled from 153 patients, 123 were from 95 tuberculous patients. The sensitivity and specificity of MTD were 93 and 100%, respectively. The sensitivity of culture was 89%.
Differential Recovery ofCandidaSpecies from Subgingival Sites in Human Immunodeficiency Virus-Positive and Healthy Children from Rio de Janeiro, Brazil
Authors: Portela M. B. , Souza I. P. R. , Costa E. M. M. B. , Hagler A. N. , Soares R. M. A. , Santos A. L. S.
Published: December 2004

The prevalence of subgingivalCandidaspecies was studied in 52 human immunodeficiency virus (HIV)-positive and 42 HIV-negative children.Candidawas cultured from 22 (42.3%) and 3 (7.1%) HIV-infected and control children, respectively.C. albicanswas the most commonCandidaspecies isolated from HIV-infected children, followed byC. dubliniensis,C. glabrata, andC. tropicalis. In the HIV-positive group, the prevalence ofCandidaisolation was significantly higher in children who presented with low CD4+-T-lymphocyte counts, elevated viral loads, and gingivitis.
Risk of injury for occupants of motor vehicle collisions from unbelted occupants
Authors: MacLennan P A , McGwin G , Metzger J , Moran S G , Rue L W
Published: December 2004

Objective:Unbelted occupants may increase the risk of injury for other occupants in a motor vehicle collision (MVC). This study evaluated the association between occupant restraint use and the risk of injury (including death) to other vehicle occupants.

Design:A population based cohort study.

Setting:United States.

Subjects:MVC occupants (n = 152 191 unweighted, n = 18 426 684 weighted) seated between a belted or unbelted occupant and the line of the principal direction of force in frontal, lateral, and rear MVCs were sampled from the 1991–2002 National Automotive Sampling System General Estimates System. Offset MVCs were not included in the study.

Main outcome measure:Risk ratios and 95% confidence intervals for injury (including death) for occupants seated contiguous to unbelted occupants compared to occupants seated contiguous to belted occupants. Risk ratios were adjusted for at risk occupant’s sex, age, seating position, vehicle type, collision type, travel speed, crash severity, and at risk occupants’ own seat belt use.

Results:Exposure to unbelted occupants was associated with a 40% increased risk of any injury. Belted at risk occupants were at a 90% increased risk of injury but unbelted occupants were not at increased risk. Risks were similar for non-incapacitating and capacitating injuries. There was a 4.8-fold increased risk of death for exposed belted occupants but no increased risk of death for unbelted occupants.

Conclusions:Belted occupants are at an increased risk of injury and death in the event of a MVC from unbelted occupants.
Acoustical methods for the investigation of adhesively bonded structures: A review
Authors: Maeva Elena , Severina Inna , Bondarenko Sergiy , Chapman Gilbert , O'Neill Brian , Severin Fedar , Maev Roman Gr.
Published: December 2004

Acoustical methods have been widely used for almost 30 years for flaw detection, visualization, and local parameter measurement of different materials. Acoustical techniques are irreplaceable tools for nondestructive evaluation of adhesive-bonded composites and components for the electronics, aeronautics, and automotive industries in the high-technology sector. In the last decade, much progress has been made in the development and improvement of acoustical methods for the investigation of adhesively-bonded structures. These methods allow us to detect voids, delaminations, porosities, cracks, and poor adhesion. In this paper, the most common techniques, such as normal and oblique ultrasonic scans, resonant ultrasonic spectroscopy, and Lamb-wave methods are reviewed. Analysis of the typical defects that can occur in adhesive joints and their causes are presented. The progress of the study of the adhesion mechanism and the role of the interfacial properties and surface conditions in the adhesion process is surveyed. PACS No.: 81.70.Cv
Adrenomedullin expression in a rat model of acute lung injury induced by hypoxia and LPS
Authors: Agorreta Jackeline , Zulueta Javier J. , Montuenga Luis M. , Garayoa Mercedes
Published: December 2004

Adrenomedullin (ADM) is upregulated independently by hypoxia and LPS, two key factors in the pathogenesis of acute lung injury (ALI). This study evaluates the expression of ADM in ALI using experimental models combining both stimuli: an in vivo model of rats treated with LPS and acute normobaric hypoxia (9% O2) and an in vitro model of rat lung cell lines cultured with LPS and exposed to hypoxia (1% O2). ADM expression was analyzed by in situ hybridization, Northern blot, Western blot, and RIA analyses. In the rat lung, combination of hypoxia and LPS treatments overcomes ADM induction occurring after each treatment alone. With in situ techniques, the synergistic effect of both stimuli mainly correlates with ADM expression in inflammatory cells within blood vessels and, to a lesser extent, to cells in the lung parenchyma and bronchiolar epithelial cells. In the in vitro model, hypoxia and hypoxia + LPS treatments caused a similar strong induction of ADM expression and secretion in epithelial and endothelial cell lines. In alveolar macrophages, however, LPS-induced ADM expression and secretion were further increased by the concomitant exposure to hypoxia, thus paralleling the in vivo response. In conclusion, ADM expression is highly induced in a variety of key lung cell types in this rat model of ALI by combination of hypoxia and LPS, suggesting an essential role for this mediator in this syndrome.
Influence of brain angiotensin on thermoregulation and hydromineral balance during pregnancy in rats
Authors: Cairns Melissa J. , Burns Peta , Di Nicolantonio Robert , McKinley Michael J. , Mathai Michael L.
Published: December 2004

During mammalian pregnancy, body temperature decreases and there are changes in fluid and electrolyte balance. Angiotensin signaling mechanisms in the brain have been shown to influence thermoregulation and body fluid balance in the nonpregnant state. We hypothesized that brain angiotensin is also implicated in adjusting these physiological systems in the pregnant rat. We compared core temperature and fluid regulation in three groups of pregnant rats: untreated rats, rats receiving continuous infusion of an AT1 antagonist candesartan (5 μg·kg−1·day−1) into a lateral cerebral ventricle to block brain AT1 receptors, and rats receiving vehicle [artificial cerebrospinal fluid (aCSF)] vehicle. Untreated and aCSF-treated rats showed a decrease in colonic temperature (−0.5 and −0.8°C respectively) by day 20 of gestation. However, rats treated with candesartan had increased colonic temperature compared with baseline (+0.9°C), and their temperature was significantly higher on days 7 ( P < 0.05), 17 ( P < 0.05), and 20 ( P < 0.001) compared with the other groups (aCSF and untreated). Daily food and water intakes and body weight were not different between the three groups. Similarly, litter sizes and pup weights were equal in all groups. Finally, the expected decreases in plasma Na+ and osmolality during pregnancy were equivalent in all groups. This study suggests that brain angiotensin mediates the progressive decrease in body temperature that occurs during pregnancy. However, the changes in fluid balance associated with pregnancy are not dependent on brain angiotensin.
Noradrenergic modulation of XII motoneuron inspiratory activity does not involve α2-receptor inhibition of theIhcurrent or presynaptic glutamate release
Authors: Adachi Tadafumi , Robinson Dean M. , Miles Gareth B. , Funk Gregory D.
Published: December 2004

Norepinephrine has powerful and diverse modulatory effects on hypoglossal (XII) motoneuron activity, which is important in maintaining airway patency. The objective was to test two hypotheses that α2-adrenoceptor-mediated, presynaptic inhibition of glutamatergic inspiratory drive (Selvaratnam SR, Parkis MA, and Funk GD. Brain Res 805: 104–115, 1998) and postsynaptic inhibition of the hyperpolarization-activated inward current ( Ih) (Parkis MA and Berger AJ. Brain Res 769: 108–118, 1997) modulate XII inspiratory activity. Nerve and whole cell recordings were applied to rhythmic medullary slice preparations from neonatal rats ( postnatal days 0–4) to monitor XII inspiratory burst amplitude and motoneuron properties. Application of an α2-receptor agonist (clonidine, 1 mM) to the XII nucleus reduced inspiratory burst amplitude to 71 ± 3% of control but had no effect on inspiratory synaptic currents. It also reduced the Ihcurrent by ∼40%, but an Ihcurrent blocker (ZD7288), at concentrations that blocked ∼80% of Ih, had no effect on inspiratory burst amplitude. The clonidine inhibition was unaffected by the GABAAantagonist (+)bicuculline but attenuated by the α2-antagonist rauwolscine and the imidazoline 1 (I1) antagonist efaroxan. The I1agonist rilmenidine, but not the α2-agonist UK14304, inhibited XII output. Clonidine also reduced action potential amplitude or impaired repetitive firing. Although a contribution from α2, and in particular I1, receptors remains possible, results demonstrate that 1) noradrenergic modulation of XII inspiratory activity is unlikely to involve α2-receptor-mediated presynaptic inhibition of glutamate release or modulation of Ih; 2) inhibition of repetitive firing is a major factor underlying the inhibition of XII output by clonidine; and 3) Ihis present in neonatal XII motoneurons but does not contribute to shaping their inspiratory activity.
Carotid body denervation alters ventilatory responses to ibotenic acid injections or focal acidosis in the medullary raphe
Authors: Hodges M. R. , Opansky C. , Qian B. , Davis S. , Bonis J. M. , Krause K. , Pan L. G. , Forster H. V.
Published: December 2004

Our aim was to determine the effects of carotid body denervation (CBD) on the ventilatory responses to focal acidosis and ibotenic acid (IA) injections into the medullary raphe area of awake, adult goats. Multiple microtubules were chronically implanted into the midline raphe area nuclei either before or after CBD. For up to 15 days after bilateral CBD, arterial Pco2 (PaCO2) (13.3 ± 1.9 Torr) was increased ( P < 0.001), and CO2 sensitivity (−53.0 ± 6.4%) was decreased ( P < 0.001). Thereafter, resting PaCO2 and CO2 sensitivity returned ( P < 0.01) toward control, but PaCO2 remained elevated (4.8 ± 1.9 Torr) and CO2 sensitivity reduced (−24.7 ± 6.0%) ≥40 days after CBD. Focal acidosis (FA) at multiple medullary raphe area sites 23–44 days post-CBD with 50 or 80% CO2 increased inspiratory flow (V̇i), tidal volume (Vt), metabolic rate (V̇o2), and heart rate (HR) ( P < 0.05). The effects of FA with 50% CO2 after CBD did not differ from intact goats. However, CBD attenuated ( P < 0.05) the increase in V̇i, Vt, and HR with 80% CO2, but it had no effect on the increase in V̇o2. Rostral but not caudal raphe area IA injections increased V̇i, BP, and HR ( P < 0.05), and these responses were accentuated ( P < 0.001) after CBD. CO2 sensitivity was attenuated (−20%; P < 0.05) <7 days after IA injection, but thereafter it returned to prelesion values in CBD goats. We conclude the following: 1) the attenuated response to FA after CBD provides further evidence that the carotid bodies provide a tonic facilitory input into respiratory control centers, 2) the plasticity after CBD is not due to increased raphe chemoreceptor sensitivity, and 3) the “error-sensing” function of the carotid body blunts the effect of strong stimulation of the raphe.
Prior heavy-intensity exercise speeds V̇o2 kinetics during moderate-intensity exercise in young adults
Authors: Gurd Brendon J. , Scheuermann Barry W. , Paterson Donald H. , Kowalchuk John M.
Published: December 2004

The effect of prior heavy-intensity warm-up exercise on subsequent moderate-intensity phase 2 pulmonary O2 uptake kinetics (τV̇o2) was examined in young adults exhibiting relatively fast (FK; τV̇o2 < 30 s; n = 6) and slow (SK; τV̇o2 > 30 s; n = 6) V̇o2 kinetics in moderate-intensity exercise without prior warm up. Subjects performed four repetitions of a moderate (Mod1)-heavy-moderate (Mod2) protocol on a cycle ergometer with work rates corresponding to 80% estimated lactate threshold (moderate intensity) and 50% difference between lactate threshold and peak V̇o2 (heavy intensity); each transition lasted 6 min, and each was preceded by 6 min of cycling at 20 W. V̇o2 and heart rate (HR) were measured breath-by-breath and beat-by-beat, respectively; concentration changes of muscle deoxyhemoglobin (HHb), oxyhemoglobin, and total hemoglobin were measured by near-infrared spectroscopy (Hamamatsu NIRO 300). τV̇o2 was lower ( P < 0.05) in Mod2 than in Mod1 in both FK (20 ± 5 s vs. 26 ± 5 s, respectively) and SK (30 ± 8 s vs. 45 ± 11 s, respectively); linear regression analysis showed a greater “speeding” of V̇o2 kinetics in subjects exhibiting a greater Mod1 τV̇o2. HR, oxyhemoglobin, and total hemoglobin were elevated ( P < 0.05) in Mod2 compared with Mod1. The delay before the increase in HHb was reduced ( P < 0.05) in Mod2, whereas the HHb mean response time was reduced ( P < 0.05) in FK (Mod2, 22 ± 3 s; Mod1, 32 ± 11 s) but not different in SK (Mod2, 36 ± 13 s; Mod1, 34 ± 15 s). We conclude that improved muscle perfusion in Mod2 may have contributed to the faster adaptation of V̇o2, especially in SK; however, a possible role for metabolic inertia in some subjects cannot be overlooked.
Optimal oxygen pressure and time for reduced bubble formation in theN2-saturated decompressed prawn
Authors: Ertracht O. , Arieli R. , Arieli Y. , Ron R. , Erlichman Z. , Adir Y.
Published: December 2004

Bubbles that grow during decompression are believed to originate from preexisting gas micronuclei. We showed that pretreatment of prawns with 203 kPa oxygen before nitrogen loading reduced the number of bubbles that evolved on decompression, presumably owing to the alteration or elimination of gas micronuclei (Arieli Y, Arieli R, and Marx A. J Appl Physiol 92: 2596–2599, 2002). The present study examines the optimal pretreatment for this assumed crushing of gas micronuclei. Transparent prawns were subjected to various exposure times (0, 5, 10, 15, and 20 min) at an oxygen pressure of 203 kPa and to 5 min at different oxygen pressures (Po2 values of 101, 151, 203, 405, 608, and 810 kPa), before nitrogen loading at 203 kPa followed by explosive decompression. After the decompression, bubble density and total gas volume were measured with a light microscope equipped with a video camera. Five minutes at a Po2 of 405 kPa yielded maximal reduction of bubble density and total gas volume by 52 and 71%, respectively. It has been reported that 2–3 h of hyperbaric oxygen at bottom pressure was required to protect saturation divers decompressed on oxygen against decompression sickness. If there is a shorter pretreatment that is applicable to humans, this will be of great advantage in diving and escape from submarines.
Dynamic response characteristics of local muscle blood flow regulatory mechanisms in human forearm exercise
Authors: Saunders Natasha R. , Pyke Kyra E. , Tschakovsky Michael E.
Published: December 2004

We sought to understand the nature of control mechanisms involved in the adaptation of exercising muscle hyperemia. Seven subjects performed rhythmic dynamic forearm exercise under two exercise conditions: small step 1 [step increase from rest to 40% peak forearm vascular conductance (FVC), in ml·min−1·100 mmHg−1] for 5 min followed by small step 2 (further increase to 80% peak FVC for 5 min), and large step (step increase from rest to 80% peak FVC for 5 min). FVC data were fit with a two- (small step 1) and three-component (small step 2, large step) exponential as appropriate. For the rapid phase I response, FVC dynamic response characteristics (time delay, time constant) were not affected by the magnitude of the work intensity increase when the transition began from rest, but were slower in the 40–80% transition. Rest-80% gain was greater than either rest-40% or 40–80% transitions but represented the same proportion of the phase I + phase II gain across all transitions (57 vs. 56 vs. 57%, respectively, P = 0.975). For the slower phase II response, dynamic response characteristics were not affected by the magnitude of the work intensity increase when initiated from rest. The time constant was not altered when the transition began from exercise vs. rest. We conclude that 1) dynamic response characteristics of exercise hyperemia control mechanisms are not affected by the magnitude of work rate increase when forearm exercise is initiated from rest, 2) phase I but not phase II dynamic response characteristics are sensitive to baseline exercise intensity, and 3) the mechanisms contributing to phase I result in the same relative response magnitude, regardless of the size of the step increase in exercise intensity or the baseline from which it is initiated.
On Traits, Situations, and Their Integration: A Developmental Perspective
Authors: Roberts Brent W. , Pomerantz Eva M.
Published: December 2004

The question of whether the person or the situation is largely responsible for behavior has plagued psychology intermittently for the last half century. Studies of the heritability, stability, and consensual validity of traits have clearly demonstrated the existence of traits. However, there is continuing controversy about the role of traits and situations in the enterprise of personality psychology. The goal of this article is to describe how insights yielded from adopting a developmental approach can foster the successful integration of the person and the situation across the life span. Five key lessons are described: (a) age matters—studying different age groups can lead to biases for and against traits and situations; (b), if age matters, time matters more—longitudinal and within-participant designs demonstrate that traits and situations are reciprocally related; (c) examine multiple types of change—focusing on one type, such as mean-level change, can lead to inappropriate conclusions about the merits of persons or situations; (d) be sensitive to levels of analysis—the relative breadth of persons and situations may determine the relative influence of the two; (e) pay attention to process—process models lead inextricably to transactional explanations.
Water Splitting into H2 and O2 over Cs2Nb4O11 Photocatalyst
Authors: Miseki Yugo , Kato Hideki , Kudo Akihiko
Published: December 2004

Photophysical and photocatalytic properties of Cs2Nb4O11 consisting of NbO6 octahedra and NbO4 tetrahedra were investigated. The band gap of Cs2Nb4O11 was 3.7 eV. Broad blue photoluminescence was observed at 77 K. Pretreated NiO-loaded Cs2Nb4O11 showed a high activity for water splitting under UV-light irradiation.
Evaluation of compressed video-images for emergency telemedicine work with trauma patients
Authors: Kim Dong-Keun , Yoo Sun K , Kang Ho-Hyun , Park In-Cheol , Youn Yoo S , Kim Seung H
Published: December 2004

Video-encoders in telemedicine systems need to adjust their coding methods for operation on heterogeneous networks on which bandwidth fluctuates. We evaluated MPEG-4 compressed video-pictures of three trauma patients. We compared the original video-frames with compressed video-frames in terms of the peak signal-to-noise ratio (PSNR). In a qualitative evaluation, three emergency specialists scored the quality of the video-images blind, on a five-point scale (1 =bad to 5=excellent). The PSNR increased as the bit rate increased from 0.2 to 6 Mbit/s. When the bit rate was fixed, in other words at a given network bandwidth, a higher PSNR was obtained at the expense of spatial resolution and frame rate. The video quality was highly affected by the amount of camera shake. Emergency telemedicine systems require a high bit rate, high spatial resolution and a high frame rate to achieve optimum video quality. However, if the bandwidth is limited (i.e. the bit rate is fixed), temporal resolution becomes more important than spatial resolution.
A feasibility study of email communication between the patient's family and the specialist burns team
Authors: Johansen Monika Alise , Wootton Richard , Kimble Roy , Mill Julie , Smith Anthony , Hockey Andrew
Published: December 2004

We investigated whether the parents of burns patients could capture suitable clinical images with a digital camera and add the necessary text information to enable the paediatric burns team to provide follow-up care via email. Four families were involved in the study, each of whom sent regular email consultations for six months. The results were very encouraging. The burns team felt confident that the clinical information in 30 of the 32 email messages (94%) they received was accurate, although in 11 of these 30 cases (37%) they stated that there was room for improvement (the quality was nonetheless adequate for clinical decision making). The study also showed that low-resolution images (average size 37 kByte) were satisfactory for diagnosis. Families were able to participate in the service without intensive training and support. The user survey showed that all four families found it easy and convenient to take the digital photographs and to participate in the study. The results suggest that the technique has potential as a low-cost telemedicine service in burns follow-up, and that it requires only modest investment in equipment, training and support.
A study of the use of hand-held devices in an emergency department
Authors: Gururajan Raj
Published: December 2004

In a project conducted in 2002 and 2003, the use of hand-held computing devices was examined in a hospital emergency department in Western Australia. Personal digital assistants (PDAs) were used for the wireless development. The study addressed three major issues: development methodology, communication between the mobile devices and existing databases, and user interfaces. The software was tested by about 20 health-care staff, including nurses, doctors, administration staff, information technology staff and front-desk receptionists. The wireless development proved a valuable experience for everyone involved. The product is currently undergoing rigorous testing to meet the standards of the healthcare industry.
Fractionally spaced blind equalization with low‐complexity concurrent constant modulus algorithm and soft decision‐directed scheme
Authors: Chen S. , Chng E. S.
Published: December 2004

The paper proposes a low‐complexity concurrent constant modulus algorithm (CMA) and soft decision‐directed (SDD) scheme for fractionally spaced blind equalization of high‐order quadrature amplitude modulation channels. We compare our proposed blind equalizer with the recently introduced state‐of‐art concurrent CMA and decision‐directed (DD) scheme. The proposed CMA+SDD blind equalizer is shown to have simpler computational complexity per weight update, faster convergence speed, and slightly improved steady‐state equalization performance, compared with the existing CMA+DD blind equalizer. Copyright © 2004 John Wiley & Sons, Ltd.
Torsional resistance as a principal component of the structural design of long bones: Comparative multivariate evidence in birds
Authors: De Margerie Emmanuel , Sanchez Sophie , Cubo Jorge , Castanet Jacques
Published: December 2004

Here we study the occurrence of torsion‐resisting morphological and histological features (thin bone walls, circular shaft cross‐section, oblique collagen fibers, and laminar tissue arrangement) in a sample of 168 long bones from wings and legs of 22 bird species. These structural parameters were measured in mid diaphyseal undemineralized cross‐sections and analyzed using uni‐, bi‐, and multivariate (principal components analysis) data analysis techniques. We found that the four variables are significantly and positively correlated, and that covariation between variables accounts for as much as 58% of the total variation. These results suggest that torsion is a main determinant of the macro‐ and microstructural design of long bones in birds. Humerus, ulna, and femur generally possess torsion‐resisting features, while other bones (radius, carpometacarpus, tibiotarsus, tarsometatarsus, and foot phalanx) rather show bending/axial load‐resisting structural properties. These results are congruent with in vivo strain data from the literature, which reported high torsional loading in humerus and ulna during flapping flight, but also in the subhorizontal avian femur during terrestrial locomotion. The precise function of the laminar tissue spatial arrangement, the role of pneumatization, and the influence of flight mode are discussed. © 2004 Wiley‐Liss, Inc.
Myocardial expression and redistribution of GRKs in hypertensive hypertrophy and failure
Authors: Yi Xian Ping , Zhou Jibin , Baker Justin , Wang Xuejun , Gerdes A. Martin , Li Faqian
Published: December 2004

G‐protein‐coupled receptor kinases (GRKs) are involved in cardiac hypertrophy and failure. But their temporal expression and cellular localization during the development of hypertrophy and its transition to failure remains to be investigated. In this study, we determined the expression and subcellular distribution of GRK2, GRK3, GRK5, and GRK6 in cardiac myocytes of 2‐ to 24‐month‐old spontaneously hypertensive heart failure (SHHF) rats. GRK2 increased in the intercalated disks in 6‐, 12‐, and 24‐month‐old SHHF rats, although total expression remained relatively constant from 2 to 24 months in both SHHF and normotensive rats. GRK3 expression progressively increased in 6‐, 12‐, and 24‐month‐old SHHF rats and was significantly higher than in age‐matched controls. Immunolabeling of GRK3 showed a typical pattern of cross‐striations that colocalized with α‐actinin and Gαs at Z‐lines in both SHHF and control rats. GRK5 expression showed no change from 2 to 24 months in both SHHF and normotensive rats. Confocal analysis revealed nuclear translocation of GRK5 in myocytes of SHHF rats. GRK6 had a striated pattern colocalized with α‐actinin at Z‐lines in the cytoplasm and was also present in the intercalated disks of cardiac myocytes from both SHHF and control rats. GRK6 expression increased in 12‐ and 24‐month‐old SHHF rats and was significantly higher than in age‐matched controls. GRK6 labeling was reduced at the intercalated disks, but increased in the cytoplasm of cardiac myocytes from SHHF rats compared to age‐matched controls. The increased expression of GRK3 and GRK6 and subcellular redistribution of GRK2, GRK5, and GRK6 in SHHF rats may be involved in abnormal remodeling of cardiac myocytes in hypertensive hypertrophy and failure. © 2004 Wiley‐Liss, Inc.
Nucleocytoplasmic distribution of opioid growth factor and its receptor in tongue epithelium
Authors: Zagon Ian S. , Ruth Torre B. , McLaughlin Patricia J.
Published: December 2004

The subcellular distributions of the opioid growth factor (OGF), [Met5]‐enkephalin, and opioid growth factor receptor (OGFr) in the epithelium of the rat tongue were determined in order to reveal structure‐function relationships. Laser scanning confocal microscopic analysis showed that both OGF and OGFr were colocalized in the paranuclear cytoplasm and in the nuclei of keratinocytes in the stratum basale. Using immunoelectron microscopy and postembedding techniques, double labeling experiments disclosed that complexes of OGF‐OGFr were colocalized on the outer nuclear envelope, in the paranuclear cytoplasm, perpendicular to the nuclear envelope in a putative nuclear pore complex, and in the nucleus adjacent to heterochromatin. Anti‐OGF IgG alone was detected in the cytoplasm, and anti‐OGFr IgG alone was associated with the outer nuclear envelope. Study of chronic treatment with the opioid antagonist, naltrexone (NTX), which blocks opioid‐receptor binding, revealed the presence of OGFr immunoreactivity alone in the cytoplasm and the nucleus; some OGF‐OGFr complexes were also observed. Colocalization of OGFr and karyopherin (importin) β was recorded in the cytoplasm and nucleus. These results in tongue epithelium are the first to suggest that OGFr resides on the outer nuclear envelope, where OGF interacts with OGFr; that the OGF‐OGFr complex translocates between cytoplasm and nucleus at the nuclear pore; and that the nuclear localization signal of OGFr interacts with karyopherin β for nuclear transport. These novel data also indicate that signal transduction for cell proliferation appears to involve an OGF‐OGFr complex that interfaces with chromatin in the nucleus. Moreover, the unique finding that OGFr was found in the cytoplasm and nucleus in NTX‐treated specimens may suggest that NTX‐OGFr complexes have the same pathway as OGF‐OGFr. © 2004 Wiley‐Liss, Inc.
Postdefaecation pain syndrome after circular stapled anopexy is abolished by oral nifedipine
Authors: Thaha M A , Irvine L A , Steele R J C , Campbell K L
Published: December 2004

Background

Controversy has surrounded the technique of circular stapled anopexy since an isolated report of a high incidence of persistent postdefaecation pain following the procedure. The characteristics, clinical course and management of this complication have not been described.

Methods

Within an ongoing multicentre randomized clinical trial comparing circular stapled anopexy with closed haemorrhoidectomy, 77 patients underwent circular stapled anopexy. Follow-up was at 6, 12, 24 and 48 weeks. Patients underwent transanal ultrasonography, anal electrosensitivity testing and manometry.

Results

Of the 77 patients who had circular stapled anopexy, three men reported new-onset postdefaecation pain that compromised lifestyle, including ability to return to work. All three had sphincter hypertonicity on digital and manometric examination but were refractory to topical 0·2 per cent glyceryl trinitrate ointment. The addition of oral nifedipine 20 mg twice daily did not alter anal sphincter pressures but rapidly abolished symptoms and restored quality of life.

Conclusion

Postdefaecation pain is a specific complication of circular stapled anopexy, affecting a small percentage of patients. Men with a high anal sphincter pressure appear to be at risk. Although the exact aetiology remains unclear, it is likely that rectal rather than anal sphincter muscle is affected. Oral nifedipine represents an effective therapy.
Risk factors for anastomotic failure after total mesorectal excision of rectal cancer
Authors: Peeters K C M J , Tollenaar R A E M , Marijnen C A M , Klein Kranenbarg E , Steup W H , Wiggers T , Rutten H J , van de Velde C J H
Published: December 2004

Background

Anastomotic leakage is a major complication of rectal cancer surgery. The aim of this study was to investigate risk factors associated with symptomatic anastomotic leakage after total mesorectal excision (TME).

Methods

Between 1996 and 1999, patients with operable rectal cancer were randomized to receive short-term radiotherapy followed by TME or to undergo TME alone. Eligible Dutch patients who underwent an anterior resection (924 patients) were studied retrospectively.

Results

Symptomatic anastomotic leakage occurred in 107 patients (11·6 per cent). Pelvic drainage and the use of a defunctioning stoma were significantly associated with a lower anastomotic failure rate. A significant correlation between the absence of a stoma and anastomotic dehiscence was observed in both men and women, for both distal and proximal rectal tumours. In patients with anastomotic failure, the presence of pelvic drains and a covering stoma were both related to a lower requirement for surgical reintervention.

Conclusion

Placement of one or more pelvic drains after TME may limit the consequences of anastomotic failure. The clinical decision to construct a defunctioning stoma is supported by this study.
Effect of hospital caseload on long-term outcome after standardization of rectal cancer surgery at a national level
Authors: Wibe A , Eriksen M T , Syse A , Tretli S , Myrvold H E , Søreide O
Published: December 2004

Background

The purpose of this prospective study was to examine the influence of hospital caseload on long-term outcome following standardization of rectal cancer surgery at a national level.

Methods

Data relating to all 3388 Norwegian patients with rectal cancer treated for cure between November 1993 and December 1999 were recorded in a national database. Treating hospitals were divided into four groups according to their annual caseload: hospitals in group 1 (n = 4) carried out 30 or more procedures, those in group 2 (n = 6) performed 20–29 procedures, group 3 (n = 16) 10–19 procedures and group 4 (n = 28) fewer than ten procedures.

Results

The 5-year local recurrence rates were 9·2, 14·7, 12·5 and 17·5 per cent (P = 0·003) and 5-year overall survival rates were 64·4, 64·0, 60·8 and 57·8 per cent (P = 0·105) respectively in the four hospital caseload groups. An annual hospital caseload of less than ten procedures increased the risk of local recurrence compared with that in hospitals where 30 or more procedures were performed each year (hazard ratio 1·9 (95 per cent confidence interval (c.i.) 1·3 to 2·7); P < 0·001). Overall survival was lower for patients treated at hospitals with an annual caseload of less than ten versus hospitals with 30 or more (hazard ratio 1·2 (95 per cent c.i. 1·0 to 1·5); P = 0·023).

Conclusion

The rate of local recurrence was higher for hospitals with a low annual caseload of less than ten procedures than for hospitals with a high treatment volume of 30 or more. Patients treated in small hospitals also had a shorter long-term survival than those treated in large hospitals.
Ab Initio Study of the Complexes of Halogen‐Containing Molecules RX (X=Cl, Br, and I) and NH3: Towards Understanding the Nature of Halogen Bonding and the Electron‐Accepting Propensities of Covalently Bonded Halogen Atoms
Authors: Zou Jian‐Wei , Jiang Yong‐Jun , Guo Ming , Hu Gui‐Xiang , Zhang Bing , Liu Hai‐Chun , Yu Qing‐Sen
Published: December 2004

Ab initio calculations have been performed on a series of complexes formed between halogen‐containing molecules and ammonia to gain a deeper insight into the nature of halogen bonding. It appears that the dihalogen molecules form the strongest halogen‐bonded complexes with ammonia, followed by HOX; the charge‐transfer‐type contribution has been demonstrated to dominate the halogen bonding in these complexes. For the complexes involving carbon‐bound halogen molecules, our calculations clearly indicate that electrostatic interactions are mainly responsible for their binding energies. Whereas the halogen‐bond strength is significantly enhanced by progressive fluorine substitution, the substitution of a hydrogen atom by a methyl group in the CH3X⋅⋅⋅NH3complex weakened the halogen bonding. Moreover, remote substituent effects have also been noted in the complexes of halobenzenes with differentparasubstituents. The influence of the hybridization state of the carbon atom bonded to the halogen atom has also been examined and the results reveal that halogen‐bond strengths decrease in the order HCCX>H2CCHX≈OCHX≈C6H5X>CH3X. In addition, several excellent linear correlations have been established between the interaction energies and both the amount of charge transfer and the electrostatic potentials corresponding to an electron density of 0.002 au along the RX axis; these correlations provide good models with which to evaluate the electron‐accepting abilities of the covalently bonded halogen atoms. Finally, some positively charged halogen‐bonded systems have been investigated and the effect of the charge has been discussed.
Experimental and Computational Studies of Hydrogen Bonding and Proton Transfer to [Cp*Fe(dppe)H]
Authors: Belkova Natalia V. , Collange Edmond , Dub Pavel , Epstein Lina M. , Lemenovskii Dmitrii A. , Lledós Agustí , Maresca Olivier , Maseras Feliu , Poli Rinaldo , Revin Pavel O. , Shubina Elena S. , Vorontsov Evgenii V.
Published: December 2004

The present contribution reports experimental and computational investigations of the interaction between [Cp*Fe(dppe)H] and different proton donors (HA). The focus is on the structure of the proton transfer intermediates and on the potential energy surface of the proton transfer leading to the dihydrogen complex [Cp*Fe(dppe)(H2)]+. With p‐nitrophenol (PNP) a UV/Visible study provides evidence of the formation of the ion‐pair stabilized by a hydrogen bond between the nonclassical cation [Cp*Fe(dppe)(H2)]+ and the homoconjugated anion ([AHA]−). With trifluoroacetic acid (TFA), the hydrogen‐bonded ion pair containing the simple conjugate base (A−) in equilibrium with the free ions is observed by IR spectroscopy when using a deficit of the proton donor. An excess leads to the formation of the homoconjugated anion. The interaction with hexafluoroisopropanol (HFIP) was investigated quantitatively by IR spectroscopy and by 1H and 31P NMR spectroscopy at low temperatures (200–260 K) and by stopped‐flow kinetics at about room temperature (288–308 K). The hydrogen bond formation to give [Cp*Fe(dppe)H]⋅⋅⋅HA is characterized by ΔH°=−6.5±0.4 kcal mol−1 and ΔS°=−18.6±1.7 cal mol−1 K−1. The activation barrier for the proton transfer step, which occurs only upon intervention of a second HFIP molecule, is ΔH≠=2.6±0.3 kcal mol−1 and ΔS≠=−44.5±1.1 cal mol−1 K−1. The computational investigation (at the DFT/B3 LYP level with inclusion of solvent effects by the polarizable continuum model) reproduces all the qualitative findings, provided the correct number of proton donor molecules are used in the model. The proton transfer process is, however, computed to be less exothermic than observed in the experiment.