bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ocular parameters related to drug delivery in the canine and equine eye: aqueous and vitreous humor volume and scleral surface area and thickness
Authors: Gilger Brian C. , Reeves Keri‐Ann , Salmon Jacklyn H. 
Published: July 2005

AbstractObjective  To measure the ocular surface area, scleral thickness, and the aqueous and vitreous humor volumes in the canine and equine eye.Animals studied  Fourteen canine and 16 equine cadaver eyes.Procedure  Eyes were measured either fresh or following fixation in formalin. Ocular surface area was calculated using the fluid displacement method. Globes were hemisected and aqueous and vitreous humor were collected and quantitated. Scleral thickness was measured by digital caliper, by image projection, and by ultrasonic biomicroscopy (UBM).Results  Mean ± standard deviation (SD) scleral surface areas in canine and equine eyes were 12.87 ± 2.24 and 57.23 ± 5.63 cm2, respectively. Mean ± SD aqueous humor volume was 0.77 ± 0.24 in the dog and 3.04 ± 1.27 mL in the horse. Mean vitreous humor volume was 1.7 ± 0.86 mL for the canine eye and 26.15 ± 4.87 mL for the equine eye. In canine and equine eyes, the sclera was thinnest at the ocular equator: 0.34 ± 0.13 mm (canine) and 0.53 ± 0.1 (equine). There were no significant differences between the direct caliper and projected thickness measurements or differences between measurements in the superior, inferior, nasal, and temporal quadrants of the eye. Scleral thickness in fresh tissue was greater than in fixed tissue at most sites.Conclusions  The UBM measurement method appeared to be most consistent and reproducible when compared to direct measurement techniques. Formalin fixation of the eyes was associated with significantly thinner scleral tissue than with fresh ocular tissue.
How the Spatial Frequency of Polarization Influences the Induction of Reentry in Cardiac Tissue
Authors: BEAUDOIN DEBORAH LANGRILL , ROTH BRADLEY J. 
Published: July 2005

Introduction: The mechanism by which an electric field induces a rotor during cross‐field stimulation of cardiac tissue is not entirely known. Different heterogeneous aspects of cardiac tissue have been offered as possible theories, a prominent one being fiber curvature. The polarization produced when an electric field is applied to a sheet of tissue is varied over many spatial frequencies, depending upon the fiber angle. This article compares the effect of high and low spatial frequencies of polarization on reentry induction. Methods and Results: We incorporate a randomized fiber angle geometry into a two‐dimensional active cardiac tissue model with unequal anisotropy ratios already exhibiting smooth, curving fibers. We simulate cross‐field stimulation to initiate reentry in the tissue model, and compare the electric field thresholds at different S1–S2 intervals for tissue with randomized fiber angles, tissue with a smooth fiber geometry, and tissue with randomized fiber angles plus smooth, curving fibers. The tissue with both small, random fiber angles and curving fibers has a significantly lower threshold for reentry at certain intervals on the strength‐interval curve than for the two cases individually. Conclusion: Cardiac tissue exhibiting a random fiber geometry in conjunction with a smooth fiber geometry includes high and low spatial frequencies of polarization that may have an effect on the mechanism for reentry at certain S1–S2 intervals. Low spatial frequency regions of hyperpolarization carve out excitable pathways, and high spatial frequency regions provide the large gradient of transmembrane potential required to initiate break excitation.
Assessment of Cardiac Baroreflex Function During Fixed Atrioventricular Pacing Using Baroreceptor‐Stroke Volume Reflex Sensitivity
Authors: YASUMASU TOMIYA , ABE HARUHIKO , OGINOSAWA YASUSHI , TAKAHARA KAZUO , NAKASHIMA YASUHIDE 
Published: July 2005

Introduction: The baroreceptor‐heart rate (HR) reflex has prognostic value in cardiovascular medicine. However, it cannot be used in chronotropically incompetent or paced patients. In healthy subjects, the baroreceptor‐stroke volume (SV) reflex, with power spectral analysis of SV and blood pressure (BP) variations in the low‐frequency band, serves as an alternate measure of the baroreceptor‐cardiac reflex. This study examined the baroreceptor‐stroke volume (SV) reflex sensitivity in the supine and 60° upright positions in paced patients. Methods and Results: We studied 16 recipients of dual‐chamber pacemakers paced at a fixed rate. The hemodynamics and baroreceptor‐SV reflex sensitivity were measured during atrioventricular (AV) sequential pacing every 5 minute in the supine and 60° upright positions. Mean SV decreased from 42.0 ± 20.1 mL in the supine to 36.6 ± 16.1 mL in the upright position (P < 0.05), whereas BP and total peripheral resistance did not change. A significant fall in baroreceptor‐SV reflex sensitivity from 29.2 ± 18.0%/mmHg to 19.5 ± 15.5%/mmHg was observed during upright tilt (P < 0.005). Conclusion: Fixed‐rate AV sequential pacing did not blunt the decrease in baroreceptor‐SV reflex sensitivity consistent with the arterial baroreflex gain response to upright posture. The decreased baroreceptor‐SV reflex sensitivity occurring with the upright posture may reflect a baroreflex‐induced inotropic effect secondary to vagal withdrawal and sympathetic activation.
Gold‐Tip Electrodes—A New “Deep Lesion” Technology for Catheter Ablation? In Vitro Comparison of a Gold Alloy Versus Platinum–Iridium Tip Electrode Ablation Catheter
Authors: LEWALTER THORSTEN , BITZEN ALEXANDER , WURTZ, Ph.D. SABINE , BLUM, Ph.D. ROBERT , SCHLODDER, Ph.D. KARSTEN , YANG ALEXANDER , LICKFETT LARS , SCHWAB JÖRG O. , SCHRICKEL JAN W. , TIEMANN KLAUS , LINHART MARKUS , ZIMA ENDRE , MERKELY BELA , LÜDERITZ BERNDT 
Published: July 2005

Radiofrequency (RF) catheter ablation is widely used to induce focal myocardial necrosis using the effect of resistive heating through high‐frequency current delivery. It is current standard to limit the target tissue–electrode interface temperature to a maximum of 60–70°C to avoid char formation. Gold (Au) exhibits a thermal conductivity of nearly four times greater than platinum (Pt–Ir) (3.17 W/cm Kelvin vs 0.716 W/cm Kelvin), it was therefore hypothesized that RF ablation using a gold electrode would create broader and deeper lesions as a result of a better heat conduction from the tissue–electrode interface and additional cooling of the gold electrode by “heat loss” to the intracardiac blood. Both mechanisms would allow applying more RF power to the tissue before the electrode–tissue interface temperature limit is reached. To test this hypothesis, we performed in vitro isolated liver and pig heart investigations comparing lesion depths of a new Au‐alloy‐tip electrode to standard Pt–Ir electrode material.Mean lesion depth in liver tissue for Pt–Ir was 4.33 ± 0.45 mm (n = 60) whereas Au electrode was able to achieve significantly deeper lesions (5.86 ± 0.37 mm [n = 60; P < 0.001]). The mean power delivered using Pt–Ir was 6.95 ± 2.41 W whereas Au tip electrode delivered 9.64 ± 3.78 W indicating a statistically significant difference (P < 0.05). In vitro pig heart tissue Au ablation (n = 20) increased significantly the lesion depth (Au: 4.85 ± 1.01 mm, Pt–Ir: 2.96 ± 0.81 mm, n = 20; P < 0.001). Au tip electrode again applied significantly more power (P < 0.001).Gold‐tip electrode catheters were able to induce deeper lesions using RF ablation in vitro as compared to Pt–Ir tip electrode material. In liver and in pig heart tissue, the increase in lesion depth was associated with a significant increase in the average power applied with the gold electrode at the same level of electrode–tissue temperature as compared to platinum material.
Thermal fatigue in hot‐working tools
Authors: Sjöström Johnny , Bergström Jens 
Published: July 2005

Hot‐working, in general, is one of the fundaments of the industrialised society and the hot‐work tool, which gives the part its basic shape, is one of the most essential elements. Most hot‐working tools are subjected to extreme temperature variations, which give rise to stresses and strains and may eventually lead to thermal fatigue.Two hot forming applications have been studied, hot forging and die casting. Tools from these applications were examined to determine damage, material response, thermal fatigue crack initiation and propagation. Surface strain measurements during thermal fatigue testing were performed on the tool material to evaluate the surface mechanical strain levels during typical thermal cycling. Isothermal fatigue testing was also performed to determine the stress–strain response in the temperature interval 200–600°C. It was found that thermal fatigue crack initiation occurs within 1% of the tools life in both applications.
ANTIMICROBIAL RESISTANCE IN SALMONELLA ENTERITIDIS ISOLATED FROM FOODS INVOLVED IN HUMAN FOODBORNE OUTBREAKS THAT OCCURRED IN THE SOUTH OF BRAZIL, 1999–2000
Authors: GEIMBA M. P. , TONDO E. C. , BRANDELLI A. 
Published: July 2005

ABSTRACT Antimicrobial resistance was determined for 73 isolates of Salmonella enteritidis isolated from foods involved in human foodborne outbreaks that occurred in the South of Brazil, from 1999 to 2000. The isolates were individually tested against 10 antimicrobial agents using a disc diffusion method. Most isolates were susceptible to all drugs tested. No S. enteritidis isolates were resistant to sulfamethoxazole/trimethoprim or chloramphenicol. The predominant resistance observed was to streptomycin (S) (37%), gentamicin (GEN) (13.7%) and nalidixic acid (NAL) (13.7%), while intermediate resistance was observed most often for tetracycline (53.4%), neomycin (NEO) (30.1%) and GEN (15.1%). Resistance was verified in 40 isolates (54%), which were grouped in 15 different patterns. Multiple resistance was presented in 17 (23%) of the isolates, and one isolate exhibited resistance to four drugs (NEO, kanamycin, S and NAL), demonstrating the involvement of multiresistant S. enteritidis strains with foodborne outbreaks.
THE RELATIONSHIP OF RAZOR BLADE SHEAR, ALLO‐KRAMER SHEAR, WARNER‐BRATZLER SHEAR AND SENSORY TESTS TO CHANGES IN TENDERNESS OF BROILER BREAST FILLETS
Authors: CAVITT L.C. , MEULLENET J.‐F.C. , XIONG R. , OWENS C.M. 
Published: July 2005

ABSTRACT This study evaluated the ability of the razor blade (RB) shearing method and various other instrumental shearing methods as a means for developing models to predict tenderness in broiler breast fillets. Breast fillets were subjected to either shear analysis (razor, Allo‐Kramer or Warner‐Bratzler) or sensory evaluation (trained descriptive or consumer). The relationships between the instrumental and the descriptive sensory attributes exhibited coefficients of determination of 0.53 < R2 < 0.73 for initial hardness and chewdown hardness, while the relationships between the instrumental and the consumer sensory attributes of tenderness acceptability and intensity had coefficients of determination ranging between 0.71 < R2 < 0.97. For both descriptive and consumer sensory analyses, the instrumental shear tests performed similarly for predicting the tenderness of cooked broiler breast meat. The RB shear test for assessing meat tenderness had advantages, in that no sample cutting or weighing was required to execute the test nor was it excessively destructive, as only a small incision was made in the sample.
Effects of Incubation Temperature on Growth and Production of Exopolysaccharides by an Antarctic Sea Ice Bacterium Grown in Batch Culture
Authors: Nichols Carol Mancuso , Bowman John P. , Guezennec Jean 
Published: July 2005

ABSTRACT

The sea ice microbial community plays a key role in the productivity of the Southern Ocean. Exopolysaccharide (EPS) is a major component of the exopolymer secreted by many marine bacteria to enhance survival and is abundant in sea ice brine channels, but little is known about its function there. This study investigated the effects of temperature on EPS production in batch culture by CAM025, a marine bacterium isolated from sea ice sampled from the Southern Ocean. Previous studies have shown that CAM025 is a member of the genus
Pseudoalteromonas
and therefore belongs to a group found to be abundant in sea ice by culture-dependent and -independent techniques. Batch cultures were grown at −2°C, 10°C, and 20°C, and cell number, optical density, pH, glucose concentration, and viscosity were monitored. The yield of EPS at −2°C and 10°C was 30 times higher than at 20°C, which is the optimum growth temperature for many psychrotolerant strains. EPS may have a cryoprotective role in brine channels of sea ice, where extremes of high salinity and low temperature impose pressures on microbial growth and survival. The EPS produced at −2°C and 10°C had a higher uronic acid content than that produced at 20°C. The availability of iron as a trace metal is of critical importance in the Southern Ocean, where it is known to limit primary production. EPS from strain CAM025 is polyanionic and may bind dissolved cations such at trace metals, and therefore the presence of bacterial EPS in the Antarctic marine environment may have important ecological implications.
Long-Term Population Dynamics of Phototrophic Sulfur Bacteria in the Chemocline of Lake Cadagno, Switzerland
Authors: Tonolla Mauro , Peduzzi Raffaele , Hahn Dittmar 
Published: July 2005

ABSTRACT

Population analyses in water samples obtained from the chemocline of crenogenic, meromictic Lake Cadagno, Switzerland, in October for the years 1994 to 2003 were studied using in situ hybridization with specific probes. During this 10-year period, large shifts in abundance between purple and green sulfur bacteria and among different populations were obtained. Purple sulfur bacteria were the numerically most prominent phototrophic sulfur bacteria in samples obtained from 1994 to 2001, when they represented between 70 and 95% of the phototrophic sulfur bacteria. All populations of purple sulfur bacteria showed large fluctuations in time with populations belonging to the genus
Lamprocystis
being numerically much more important than those of the genera
Chromatium
and
Thiocystis
. Green sulfur bacteria were initially represented by
Chlorobium phaeobacteroides
but were replaced by
Chlorobium clathratiforme
by the end of the study.
C. clathratiforme
was the only green sulfur bacterium detected during the last 2 years of the analysis, when a shift in dominance from purple sulfur bacteria to green sulfur bacteria was observed in the chemocline. At this time, numbers of purple sulfur bacteria had decreased and those of green sulfur bacteria increased by about 1 order of magnitude and
C. clathratiforme
represented about 95% of the phototrophic sulfur bacteria. This major change in community structure in the chemocline was accompanied by changes in profiles of turbidity and photosynthetically available radiation, as well as for sulfide concentrations and light intensity. Overall, these findings suggest that a disruption of the chemocline in 2000 may have altered environmental niches and populations in subsequent years.
Cloning and Sequencing of Two
Ceriporiopsis subvermispora
Bicupin Oxalate Oxidase Allelic Isoforms: Implications for the Reaction Specificity of Oxalate Oxidases and Decarboxylases
Authors: Escutia Marta R. , Bowater Laura , Edwards Anne , Bottrill Andrew R. , Burrell Matthew R. , Polanco Rubén , Vicuña Rafael , Bornemann Stephen 
Published: July 2005

ABSTRACT

Oxalate oxidase is thought to be involved in the production of hydrogen peroxide for lignin degradation by the dikaryotic white rot fungus
Ceriporiopsis subvermispora
. This enzyme was purified, and after digestion with trypsin, peptide fragments of the enzyme were sequenced using quadrupole time-of-flight mass spectrometry. Starting with degenerate primers based on the peptide sequences, two genes encoding isoforms of the enzyme were cloned, sequenced, and shown to be allelic. Both genes contained 14 introns. The sequences of the isoforms revealed that they were both bicupins that unexpectedly shared the greatest similarity to microbial bicupin oxalate decarboxylases rather than monocupin plant oxalate oxidases (also known as germins). We have shown that both fungal isoforms, one of which was heterologously expressed in
Escherichia coli
, are indeed oxalate oxidases that possess ≤0.2% oxalate decarboxylase activity and that the organism is capable of rapidly degrading exogenously supplied oxalate. They are therefore the first bicupin oxalate oxidases to have been described. Heterologous expression of active enzyme was dependent on the addition of manganese salts to the growth medium. Molecular modeling provides new and independent evidence for the identity of the catalytic site and the key amino acid involved in defining the reaction specificities of oxalate oxidases and oxalate decarboxylases.
Purification and Characterization of a Novel Alcohol Dehydrogenase from
Leifsonia
sp. Strain S749: a Promising Biocatalyst for an Asymmetric Hydrogen Transfer Bioreduction
Authors: Inoue Kousuke , Makino Yoshihide , Itoh Nobuya 
Published: July 2005

ABSTRACT

To find microorganisms that could reduce phenyl trifluoromethyl ketone (PTK) to (
S
)-1-phenyltrifluoroethanol [(
S
)-PTE], styrene-assimilating bacteria (ca. 900 strains) isolated from soil samples were screened. We found that
Leifsonia
sp. strain S749 was the most suitable strain for the conversion of PTK to (
S
)-PTE in the presence of 2-propanol as a hydrogen donor. The enzyme corresponding to the reaction was purified homogeneity, characterized and designated
Leifsonia
alcohol dehydrogenase (LSADH). The purified enzyme had a molecular weight of 110,000 and was composed of four identical subunits (molecular weight, 26,000). LSADH required NADH as a cofactor, showed little activity with NADPH, and reduced a wide variety of aldehydes and ketones. LSADH catalyzed the enantioselective reduction of some ketones with high enantiomeric excesses (e.e.): PTK to (
S
)-PTE (>99% e.e.), acetophenone to (
R
)-1-phenylethanol (99% e.e.), and 2-heptanone to (
R
)-2-heptanol (>99% e.e.) in the presence of 2-propanol without an additional NADH regeneration system. Therefore, it would be a useful biocatalyst.
Identification and Characterization of Pathogenic
Yersinia enterocolitica
Isolates by PCR and Pulsed-Field Gel Electrophoresis
Authors: Thisted Lambertz S. , Danielsson-Tham M.-L. 
Published: July 2005

ABSTRACT

Approximately 550 to 600 yersiniosis patients are reported annually in Sweden. Although pigs are thought to be the main reservoir of food-borne pathogenic
Yersinia enterocolitica
, the role of pork meat as a vehicle for transmission to humans is still unclear. Pork meat collected from refrigerators and local shops frequented by yersiniosis patients (
n
= 48) were examined for the presence of pathogenic
Yersinia
spp. A combined culture and PCR method was used for detection, and a multiplex PCR was developed and evaluated as a tool for efficient identification of pathogenic food and patient isolates. The results obtained with the multiplex PCR were compared to phenotypic test results and confirmed by pulsed-field gel electrophoresis (PFGE). In all, 118 pork products (91 raw and 27 ready-to-eat) were collected. Pathogenic
Yersinia
spp. were detected by PCR in 10% (9 of 91) of the raw pork samples (loin of pork, fillet of pork, pork chop, ham, and minced meat) but in none of the ready-to-eat products. Isolates of
Y. enterocolitica
bioserotype 4/O:3 were recovered from six of the PCR-positive raw pork samples; all harbored the virulence plasmid. All isolates were recovered from food collected in shops and, thus, none were from the patients' home. When subjected to PFGE, the six isolates displayed four different NotI profiles. The same four NotI profiles were also present among isolates recovered from the yersiniosis patients. The application of a multiplex PCR was shown to be an efficient tool for identification of pathogenic
Y. enterocolitica
isolates in naturally contaminated raw pork.
Isolation and Detection of Enterovirus RNA from Large-Volume Water Samples by Using the NucliSens miniMAG System and Real-Time Nucleic Acid Sequence-Based Amplification
Authors: Rutjes Saskia A. , Italiaander Ronald , van den Berg Harold H. J. L. , Lodder Willemijn J. , de Roda Husman Ana Maria 
Published: July 2005

ABSTRACT
Concentration of water samples is a prerequisite for the detection of the low virus levels that are present in water and may present a public health hazard. The aim of this study was to develop a rapid, standardized molecular method for the detection of enteroviruses in large-volume surface water samples, using a concentration method suitable for the detection of infectious viruses as well as virus RNA. Concentration of water was achieved by a conventional filter adsorption-elution method and ultrafiltration, resulting in a 10,000-fold concentration of the sample. Isolation of virus RNA by a silica-based RNA extraction method was compared with the nonmagnetic and magnetic NucliSens RNA isolation methods. By using the silica-based RNA extraction method in two out of five samples, enterovirus RNA was detected, whereas four out of five samples were positive following RNA isolation with magnetic silica beads. Moreover, estimated RNA levels increased at least 100 to 500 times. Furthermore, we compared enterovirus detection by an in-house reverse transcription (RT)-PCR with a novel commercially available real-time nucleic acid sequence-based amplification (NASBA) assay. We found that the rapid real-time NASBA assay was slightly less sensitive than our in-house RT-PCR. The advantages, however, of a commercial real-time NASBA assay, like the presence of an internal control RNA, standardization, and enormous decrease in turnaround time, makes it an attractive alternative to RT-PCR.
Changes in Race-Specific Virulence in
Pseudomonas syringae
pv. phaseolicola Are Associated with a Chimeric Transposable Element and Rare Deletion Events in a Plasmid-Borne Pathogenicity Island
Authors: Rivas Luis A. , Mansfield John , Tsiamis George , Jackson Robert W. , Murillo Jesús 
Published: July 2005

ABSTRACT

Virulence for bean and soybean is determined by effector genes in a plasmid-borne pathogenicity island (PAI) in race 7 strain 1449B of
Pseudomonas syringae
pv. phaseolicola. One of the effector genes,
avrPphF
, confers either pathogenicity, virulence, or avirulence depending on the plant host and is absent from races 2, 3, 4, 6, and 8 of this pathogen. Analysis of cosmid clones and comparison of DNA sequences showed that the absence of
avrPphF
from strain 1448A is due to deletion of a continuous 9.5-kb fragment. The remainder of the PAI is well conserved in strains 1448A and 1449B. The left junction of the deleted region consists of a chimeric transposable element generated from the fusion of homologs of IS
1492
from
Pseudomonas putida
and IS
1090
from
Ralstonia eutropha
. The borders of the deletion were conserved in 66
P. syringae
pv. phaseolicola strains isolated in different countries and representing the five races lacking
avrPphF
. However, six strains isolated in Spain had a 10.5-kb deletion that extended 1 kb further from the right junction. The perfect conservation of the 28-nucleotide right repeat of the IS
1090
homolog in the two deletion types and in the other 47 insertions of the IS
1090
homolog in the 1448A genome strongly suggests that the
avrPphF
deletions were mediated by the activity of the chimeric mobile element. Our data strongly support a clonal origin for the races of
P. syringae
pv. phaseolicola lacking
avrPphF
.