bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of two different daily dosages (2.4 vs. 1.2 g) of oral mesalazine in maintenance of remission in ulcerative colitis patients: 1‐year follow‐up study
Authors: Paoluzi O. A. , Iacopini F. , Pica R. , Crispino P. , Marcheggiano A. , Consolazio A. , Rivera M. , Paoluzi P.
Published: April 2005

Background : Mesalazine as maintenance therapy in ulcerative colitis is used worldwide and has been proven to be effective. However, the optimal dosage remains to be defined.

Aim : To establish whether daily treatment with 2.4 g of oral mesalazine is more effective than 1.2 g in preventing disease relapse.

Methods : A total of 156 patients with ulcerative colitis in remission were randomly treated for 1 year with 2.4 (n = 80) or 1.2 (n = 76) g/day of mesalazine. Activity of disease was assessed by periodical clinical, endoscopic and histological examinations.

Results : After 12 months, 24 of 80 patients (30%) on 2.4 g and 20 of 76 patients (26%) on 1.2 g were still in remission (P = N.S.). Patients in 2.4 g group remained in remission for a longer time than those in 1.2 g group (P < 0.001). Among clinical variables considered in the study, course of disease prior to enrolment (≤3/>3 relapses/year) was found to influence response to therapy.

Conclusions : A daily dosage of 2.4 g of oral mesalazine seems to better at preventing and delaying relapses of ulcerative colitis than 1.2 g. The course of disease seems to be crucial in choosing the optimal dosage of mesalazine in a maintenance regimen.
Clinical features of gastric cancer discovered after successful eradication of Helicobacter pylori: results from a 9‐year prospective follow‐up study in Japan
Authors: Kamada T. , Hata J. , Sugiu K. , Kusunoki H. , Ito M. , Tanaka S. , Inoue K. , Kawamura Y. , Chayama K. , Haruma K.
Published: April 2005

Background : Eradication of Helicobacter pylori is expected to prevent the development of gastric cancer. However, gastric cancer is sometimes discovered after successful eradication of H. pylori.

Aim : To conduct a prospective study to determine the clinical features of patients who underwent successful eradication and were later diagnosed with gastric cancer.

Methods : A total of 1787 patients (1299 males and 488 females; mean age, 58.2 years; range: 15–84) who underwent successful eradication therapy between April 1994 and March 2001 were our study subjects.

Results : Gastric cancer occurred at a rate of 1.1% (20 of 1787) during the follow‐up period. Gastric cancer comprises six of 105 (5.7%) with early gastric cancer after endoscopic resection, 12 of 575 (2.1%) with gastric ulcer and two of 453 (0.4%) with atrophic gastritis. Gastric cancer did not develop in any patient with duodenal ulcer. All patients with gastric cancer had baseline severe atrophic gastritis in the corpus.

Conclusion : Careful endoscopic examination is necessary even after successful eradication of H. pylori in patients with early gastric cancer or gastric ulcer with severe mucosal atrophy in the corpus.
Effects of aminosalicylates on thiopurine S‐methyltransferase activity: an ex vivo study in patients with inflammatory bowel disease
Authors: Xin H. , Fischer C. , Schwab M. , Klotz U.
Published: April 2005

Background : Based on in vitro experiments using recombinant human thiopurine S‐methyltransferase this enzyme is inhibited by sulfasalazine (sulphasalazine) and 5‐aminosalicylate. Thus, during treatment with azathioprine or mercaptopurine, both metabolized by thiopurine S‐methyltransferase, sulfasalazine or 5‐aminosalicylate could modify the action of azathioprine/mercaptopurine.

Aims : To examine whether this interaction is effective under ex vivo conditions.

Methods : In 18 azathioprine‐free patients and in 12 patients on azathioprine the inhibitory potential of sulfasalazine, 5‐aminosalicylate and its metabolite (Ac‐5‐aminosalicylate) was assessed by ex vivo measurement of thiopurine S‐methyltransferase in red blood cells.

Results : According to concentration response curves mean IC50 values (μm) for sulfasalazine, 5‐aminosalicylate and Ac‐5‐aminosalicylate have been calculated in three groups of azathioprine‐free patients and variable basal levels of thiopurine S‐methyltransferase activity (very high, normal and intermediate). In all three groups sulfasalazine was the strongest inhibitor (IC50: 9–17 μm) if compared with 5‐aminosalicylate (129–236) and Ac‐5‐aminosalicylate (58–74). In patients on azathioprine similar IC50 values have been calculated.

Conclusions : Comparing human plasma concentrations of sulfasalazine (15–77 μm), 5‐aminosalicylate (3–14 μm) and Ac‐5‐aminosalicylate (8–18 μm) with the IC50 values one can assume that only sulfasalazine would have the potential to inhibit thiopurine S‐methyltransferase in vivo. However, the therapeutic impact should be proved by clinical studies.
Predicting which patients can resume oral nutrition after percutaneous endoscopic gastrostomy tube placement
Authors: Naik A. D. , Abraham N. S. , Roche V. M. L. , Concato J.
Published: April 2005

Background : Percutaneous endoscopic gastrostomy tubes are placed with high frequency and relative safety for a variety of indications. One of these indications is temporary nutritional support for patients expected to resume oral nutrition.

Aims : To determine if baseline clinical characteristics can predict which patients attain the clinical goal of resuming oral nutrition with consequent tube removal.

Methods : We conducted a single site observational cohort study from December 1999 to April 2001, enrolling all patients scheduled for percutaneous endoscopic gastrostomy placement. Standard descriptive and bivariate analyses were performed. Cox proportional hazard models were constructed to identify patient characteristics prior to percutaneous endoscopic gastrostomy placement that might predict resumption of oral nutrition with tube removal.

Results : Bivariate analyses revealed four potential clinical predictors: age <65 years, localized head and neck cancer, serum albumin ≥3.75 g/dL, and serum creatinine ≤1.1 mg/dL. In multivariable analysis, age < 65 years (HR = 3.7, 95% CI: 1.0–14.3) and a diagnosis of localized head and neck cancer (HR = 4.6, 95% CI: 1.4–15.0) predicted resumption of oral nutrition with percutaneous endoscopic gastrostomy removal.

Conclusions : When discussing percutaneous endoscopic gastrostomy placement, doctors should consider the likelihood of achieving clinically important outcomes such as the resumption of oral nutrition with tube removal. This clinical goal is unlikely for older patients with diagnoses other than localized head and neck cancer.
The validity of a digital eyelid tonometer (TGDc‐01) and its comparison with Goldmann applanation tonometry – a pilot study
Authors: Lam Andrew K. C , Lam Chin Hang , Chan Rufina
Published: April 2005

Purpose:  To determine the intra‐ and inter‐examiner repeatability of a new eyelid tonometer, and its agreement with Goldmann applanation tonometry (GAT).

Materials and methods:  Forty normal subjects were recruited and their intraocular pressure was measured by two examiners using the eyelid tonometer. Examiner 1 carried out the first set of measurement, followed by examiner 2, and then examiner 1 again. Finally, a third examiner was responsible for GAT measurement. Five readings were obtained from the eyelid tonometer by each examiner each time and were masked, and three readings were obtained from GAT. The mean readings from the eyelid tonometer and GAT were used for analysis.

Results:  The intra‐examiner repeatability for the eyelid tonometer was better (around ±5 mmHg 95% of the cases) than the inter‐examiner repeatability (around ±8 mmHg 95% of the cases). The mean difference between the eyelid tonometer and GAT was small from examiner 1 (<0.5 mmHg). However, the limits of agreement were greater than the clinically acceptable level of ±3 mmHg. Examiner 2 gave an even greater difference from GAT.

Conclusions:  Similar to other recent studies, we have found that this eyelid tonometer does not provide good agreement with GAT. Different examiners could position the instrument differently and this eyelid tonometer is suggested for screening purposes only.
FRYING PERFORMANCE OF PROCESSED RICE BRAN OILS
Authors: GOPALA KRISHNA A.G. , KHATOON S. , BABYLATHA R.
Published: April 2005

Processed rice bran oils (RBOs) – refined chemically (cRBO) and physically (pRBO) – were studied for frying performance compared to sunflower oil. Their physicochemical differences showed in appearance, color and oryzanol content, partial acylglycerols and unsaponifiable matter. Bhujia was prepared in sunflower and RBOs and their frying performance measured in the oil from the bhujia. Oils after frying had deeper color (23.9–137.5% increase) and higher peroxide (101.4–274.3% increase) and free fatty acid values (−4.7 to +27.3% change) compared to the starting oils, but the RBOs studied showed lesser changes compared to the control. Oil in the bhujia was slightly lower (−7.9%) for a low‐oryzanol cRBO while it was slightly higher (+7.0%) for a high‐oryzanol pRBO. Both showed mild foaming compared to the control sunflower oil while retaining oryzanol in the oil and bhujia during frying (when partial acylglycerols caused some foaming). The bhujia retained the RBO's healthy oryzanol.
THE EFFECTS OF THERMAL AND NONTHERMAL PROCESSING METHODS ON APPLE CIDER QUALITY AND CONSUMER ACCEPTABILITY
Authors: CHOI LYNN H. , NIELSEN S. SUZANNE
Published: April 2005

Due to increased concern about the safety of fruit, vegetable and juice products, the FDA has mandated that these must undergo a 5‐log reduction in pathogens. The development of various processing methods for juice products has caused the need to determine the effects of these methods on said products. The effect of thermal pasteurization, UV irradiation and ozone treatment on apple cider quality and consumer acceptability was studied over 21 days. Thermally pasteurized samples were different in color and less preferred in all areas of consumer acceptability. UV‐irradiated samples were lower in soluble solids for the first 7 days and showed no significant difference in consumer acceptability. Ozone‐treated cider had greater sedimentation, lower sucrose content and a decrease in soluble solids by day 21. UV irradiation allows for a more cost‐effective method to produce safe apple cider with minimal quality and consumer acceptability differences.
QUALITY OF COFFEE CREAMERS AS A FUNCTION OF PROTEIN SOURCE
Authors: GOLDE A.E. , SCHMIDT K.A.
Published: April 2005

Many U.S. consumers add a sweetener or creaming agent to their brewed coffee. An ideal creamer, when added to coffee, should remain stable, dissolve readily, and provide whitening ability. In general, these properties are imparted by the protein component. Four different proteins – sodium caseinate, isolated wheat protein, soy protein isolate and whey protein concentrate – were used to formulate coffee creamers, individually and in combination, and the resultant creamers were evaluated for functionality. Coffee creamers containing plant proteins had significantly greater apparent viscosity but lower L* values than did creamers made with dairy proteins. Creamers made with higher concentrations of isolated wheat protein exhibited syneresis, whereas no syneresis occurred if sodium caseinate was the predominant protein. Only the creamer formulated with soy protein isolate alone exhibited feathering when added to hot, brewed coffee. These results indicate that coffee creamers can be formulated with plant proteins and sodium caseinate.
Modeling the Rolling of Ribbed Strip by a 3D Rigid Viscoplastic FEM
Authors: Jiang Z. Y. , Tieu A. K.
Published: April 2005

Friction at the interfaces between two rolls and a strip being plastically deformed by the rolls is an important consideration in both theory and practice of metal forming. In this paper, a 3D rigid viscoplastic finite element method (FEM) was used to model the rolling deformation of ribbed strip, taking into account friction variation in the roll bite. The calculated results such as the rolling forces, torque, and the rib height of the rolled product while considering friction variation in the roll bite are compared with the measured results obtained from the experiments. The simulation shows that when the friction variation is taken into account, the results are in good agreement with the experimental ones.
Surface Pressure Distribution on a Blade of a 10 m Diameter HAWT (Field Measurements versus Wind Tunnel Measurements)
Authors: Maeda T. , Ismaili E. , Kawabuchi H. , Kamada Y.
Published: April 2005

This paper exploits blade surface pressure data acquired by testing a three-bladed upwind turbine operating in the field. Data were collected for a rotor blade at spanwise 0.7R with the rotor disc at zero yaw. Then, for the same blade, surface pressure data were acquired by testing in a wind tunnel. Analyses compared aerodynamic forces and surface pressure distributions under field conditions against analogous baseline data acquired from the wind tunnel data. The results show that aerodynamic performance of the section 70%, for local angle of attack below static stall, is similar for free stream and wind tunnel conditions and resemblances those commonly observed on two-dimensional aerofoils near stall. For post-stall flow, it is presumed that the exhibited differences are attributes of the differences on the Reynolds numbers at which the experiments were conducted.
Modelling the Flow Around Airfoils Equipped with Vortex Generators Using a Modified 2D Navier–Stokes Solver
Authors: Nikolaou I. G. , Politis E. S. , Chaviaropoulos P. K.
Published: April 2005

Vortex generators (VGs) are commonly used for trimming the aerodynamic and aeroelastic performance of wind turbine blades by delaying flow separation. There is therefore a need for the development of reliable, still computationally affordable, models for blade designers to use to predict and enhance the aerodynamic characteristics of airfoils equipped with VGs. Such a model is proposed in the present paper, addressing in particular near-stall and post-stall airfoil performance. Starting from the three-dimensional Navier–Stokes equations that essentially describe the complex flow around a blade/VG configuration, a spanwise averaging procedure is applied, resulting in an equivalent set of two-dimensional equations, enriched with extra source terms. These terms are modelled using elementary vortex flow theory. In turbulent flows, the production term of the turbulent kinetic energy is also augmented by the vorticity induced by the VG. The model is evaluated by studying the flow past a blade section with and without VGs. An analysis of the performance of nine alternative VG configurations is also presented to demonstrate the sensitivity of the airfoil polars to the VG geometric parameters.
Dynamics of Initial Penetration in Drilling: Part 1—Mechanistic Model for Dynamic Forces
Authors: Gong Yongping , Lin Cheng , Ehmann Kornel F.
Published: April 2005

This two-part paper is aimed at developing a theoretical and numerical simulation basis for initial penetration phenomena that profoundly influence hole tolerances and shape. In Part 1, dynamic force models are developed followed by models of the drill’s dynamic behavior in Part 2. Next, these models are combined and used to predict initial penetration behavior and hole shape. A comparison of simulated and experimental results concludes Part 2. In this part, by considering the effects of drill grinding errors and drill deflections, dynamic cutting chip thickness models are developed which, in combination with workpiece surface inclination effects, allow the formulation of expressions for the dynamic chip thickness and cutting chip cross-sectional area. By using these quantities to replace their static counterparts, static drilling force models are extended to facilitate the prediction of dynamic cutting forces. Separate thrust, torque, and radial force models for the major cutting edges, secondary cutting edge, and for the indentation zone are formulated. The effects of drill installation errors on the radial cutting forces acting on the chisel edge and the major cutting edges are also included.
Condition Monitoring Using a Latent Process Model with an Application to Sheet Metal Stamping Processes
Authors: Li Xiaoli , Du R.
Published: April 2005

This paper presents a new condition monitoring method based on a latent process model. The method consists of three steps. First, a sensor signal is modeled by a latent process model that is a combination of a time-varying auto-regression model and a dynamic linear model, which decomposes the signal into several components, and each component represents a different part of the monitored system with different time-frequency behavior. Based on the latent process model, important features are extracted. Finally, using the generative topographic mapping, the selected features are mapped to a lower (two)-dimension space for classification. The proposed method is tested in condition monitoring of sheet metal stamping processes. A large number of experiments were conducted. In particular, two cases are presented in detail. From the testing results, it is found that the proposed method is able to detect various defects with a success rate around 98%. This result is significantly better than the conventional artificial neural network method. In addition, the new method is a self-organizing method and hence, little training is necessary. These advantages make the method very attractive for practical applications.
Genetic Environment and Expression of the Extended-Spectrum β-Lactamase
bla
PER-1
Gene in Gram-Negative Bacteria
Authors: Poirel Laurent , Cabanne Ludovic , Vahaboglu Haluk , Nordmann Patrice
Published: April 2005

The genetic location of the gene coding for the expanded-spectrum β-lactamase PER-1 was analyzed in a series of gram-negative isolates. It was identified as part of a composite transposon bracketed by two novel insertion elements, IS
Pa12
and IS
Pa13
, belonging to the IS
4
family that possess transposases that share 63% amino acid identity and that are chromosomally located in
Pseudomonas aeruginosa
,
Providencia stuartii
, and
Acinetobacter baumannii.
On the contrary, the
bla
PER-1
gene was identified just downstream of an IS
Pa12
element but not within a composite transposon when it was located on a plasmid in
Salmonella enterica
serovar Typhimurium and
A. baumannii
isolates. In both cases, expression of the
bla
PER-1
gene was driven by promoter sequences located in IS
Pa12
.
Biphasic Effects of Geranylgeraniol, Teprenone, and Phytol on the Growth of
Staphylococcus aureus
Authors: Inoue Yoshihiro , Hada Toshiko , Shiraishi Akiko , Hirose Kazuma , Hamashima Hajime , Kobayashi Shigeki
Published: April 2005

We examined the antibacterial activities against
Staphylococcus aureus
of three diterpenes, namely, geranylgeraniol, teprenone, and phytol, by using a broth dilution with shaking method to identify the effects of diterpenes with long aliphatic carbon chains. We also performed time-kill assays and measured the leakage of K
+
ions from bacterial cells in response to these diterpenes. The diterpenes used inhibited the growth of
S. aureus
at concentrations of 0.15 μg/ml, as determined by damage to the cell membranes, and had clear bactericidal activity. However, the inhibitory effects of the diterpenes decreased when the concentration of each was raised above a certain level. The diterpenes tested in this study appeared to have both growth-inhibitory and growth-accelerating effects, and the net effect of each depended on its concentration.
Application of an In Vitro Infection Model and Simulation for Reevaluation of Fluoroquinolone Breakpoints for
Salmonella enterica
Serotype Typhi
Authors: Booker Brent M. , Smith Patrick F. , Forrest Alan , Bullock Julie , Kelchlin Pamela , Bhavnani Sujata M. , Jones Ronald N. , Ambrose Paul G.
Published: April 2005

Salmonella enterica
serotype Typhi and nontyphoidal
Salmonella
remain major causes of morbidity and mortality worldwide. Ampicillin, trimethoprim-sulfamethoxazole, and chloramphenicol no longer provide reliable coverage of
Salmonella
, and fluoroquinoloes have emerged as first-line treatment options. Due to mounting evidence of decreased in vitro susceptibility and diminished clinical response to fluoroquinolone therapy, it has been suggested that the NCCLS breakpoints for the salmonellae be reevaluated. We utilized an in vitro infection model to determine which pharmacokinetic-pharmacodynamic (PK-PD) measure was most closely linked to fluoroquinolone activity against salmonellae and the magnitude that was predictive of efficacy. Monte Carlo simulation was utilized to determine the probability of attaining potential susceptibility breakpoints for three fluoroquinolones. The free-drug area under the concentration-time curve from 0 to 24 h/MIC ratio was the PK-PD measure most predictive of efficacy, and a ratio of 105 corresponded to 90% of maximal activity. Simulation results suggested susceptible breakpoints of 0.12 μg/ml for ciprofloxacin and gatifloxacin and 0.25 μg/ml for levofloxacin. These proposed breakpoints correspond to the MIC separating the wild-type susceptible organism population from those strains possessing single-step mutations in the quinolone resistance-determining region. These results that integrate PK-PD measures and fluoroquinolone MIC distributions in the genetic context of examined
Salmonella
isolates clearly demonstrate that the prudent use of a lower susceptibility breakpoint minimizes the probability of clinical failure or delayed response in fluoroquinolone-treated patients.
Pharmacodynamic Activity of Telithromycin at Simulated Clinically Achievable Free-Drug Concentrations in Serum and Epithelial Lining Fluid against Efflux (
mefE
)-Producing Macrolide- Resistant
Streptococcus pneumoniae
for Which Telithromycin MICs Vary
Authors: Zhanel George G. , Johanson Christel , Laing Nancy , Hisanaga Tamiko , Wierzbowski Aleksandra , Hoban Daryl J.
Published: April 2005

The present study, using an in vitro model, assessed telithromycin pharmacodynamic activity at simulated clinically achievable free-drug concentrations in serum (S) and epithelial lining fluid (ELF) against efflux (
mefE
)-producing macrolide-resistant
Streptococcus pneumoniae
. Two macrolide-susceptible (PCR negative for both
mefE
and
ermB
) and 11 efflux-producing macrolide-resistant [PCR-positive for
mefE
and negative for
ermB
)
S. pneumoniae
strains with various telithromycin MICs (0.015 to 1 μg/ml) were tested. The steady-state pharmacokinetics of telithromycin were modeled, simulating a dosage of 800 mg orally once daily administered at time 0 and at 24 h (free-drug maximum concentration [
C
max
] in serum, 0.7 μg/ml; half-life [
t
1/2
], 10 h; free-drug
C
max
in ELF, 6.0 μg/ml;
t
1/2
, 10 h). Starting inocula were 10
6
CFU/ml in Mueller-Hinton Broth with 2% lysed horse blood. Sampling at 0, 2, 4, 6, 12, 24, and 48 h assessed the extent of bacterial killing (decrease in log
10
CFU/ml versus initial inoculum). Free-telithromycin concentrations in serum achieved in the model were
C
max
0.9 ± 0.08 μg/ml, area under the curve to MIC (AUC
0-24 h
) 6.4 ± 1.5 μg · h/ml, and
t
1/2
of 10.6 ± 0.6 h. Telithromycin-free ELF concentrations achieved in the model were
C
max
6.6 ± 0.8 μg/ml, AUC
0-24 h
45.5 ± 5.5 μg · h/ml, and
t
1/2
of 10.5 ± 1.7 h. Free-telithromycin S and ELF concentrations rapidly eradicated efflux-producing macrolide-resistant
S. pneumoniae
with telithromycin MICs up to and including 0.25 μg/ml and 1 μg/ml, respectively. Free-telithromycin S and ELF concentrations simulating
C
max
/MIC ≥ 3.5 and AUC
0-24 h
/MIC ≥ 25 completely eradicated (≥4 log
10
killing) macrolide-resistant
S. pneumoniae
at 24 and 48 h. Free-telithromycin concentrations in serum simulating
C
max
/MIC ≥ 1.8 and AUC
0-24 h
/MIC ≥ 12.5 were bacteriostatic (0.1 to 0.2 log
10
killing) against macrolide-resistant
S. pneumoniae
at 24 and 48 h. In conclusion, free-telithromycin concentrations in serum and ELF simulating
C
max
/MIC ≥ 3.5 and AUC
0-24 h
/MIC ≥ 25 completely eradicated (≥4 log
10
killing) macrolide-resistant
S. pneumoniae
at 24 and 48 h.
Cloning and Characterization of a Chromosomal Class C β-Lactamase and Its Regulatory Gene in
Laribacter hongkongensis
Authors: Lau Susanna K. P. , Ho Pak-leung , Li Maria W. S. , Tsoi Hoi-wah , Yung Raymond W. H. , Woo Patrick C. Y. , Yuen Kwok-yung
Published: April 2005

Laribacter hongkongensis
, a newly discovered bacterium recently shown to be associated with community-acquired gastroenteritis, is generally resistant to most β-lactams except the carbapenems. We describe the cloning and characterization of a novel chromosomal class C β-lactamase and its regulatory gene in
L. hongkongensis
. Two genes,
ampC
and
ampR
, were cloned by inserting restriction fragments of genomic DNA from
L. hongkongensis
strain HLHK5 into pBK-CMV to give the recombinant plasmid pBK-LHK-5. The
ampR
and
ampC
genes and their promoters were divergently oriented, with the
ampR
gene immediately upstream of the
ampC
gene and an intercistronic Lys-R motif, typical of inducible
ampC-ampR
regulatory systems. The deduced amino acid sequence of the cloned AmpC β-lactamase (pI 8.1) contained consensus motifs characteristic of class C β-lactamases but had identities no greater than 46% to known class C β-lactamases. The kinetic properties of this AmpC were also compatible with those of a class C β-lactamase. PCR of 20 clinical isolates of
L. hongkongensis
, including HLHK5, showed the presence of both
ampC
and
ampR
genes in all isolates. Southern hybridization suggested that the
ampC
gene of HLHK5 was chromosomally encoded. Subcloning experiments showed that the expression of the
ampC
gene of HLHK5 was regulated by its
ampR
gene, which acts as a repressor. The β-lactamase characterized from strain HLHK5 was named LHK-5 (gene,
bla
LHK-5
) and represents the first example of AmpC β-lactamase in the β subdivision of proteobacteria.
Spread of a
Klebsiella pneumoniae
Strain Producing a Plasmid- Mediated ACC-1 AmpC β-Lactamase in a Teaching Hospital Admitting Disabled Patients
Authors: Ohana Salomon , Leflon Veronique , Ronco Esthel , Rottman Martin , Guillemot Didier , Lortat-Jacob Sylvie , Denys Pierre , Loubert Georges , Nicolas-Chanoine Marie-Helène , Gaillard Jean-Louis , Lawrence Christine
Published: April 2005

We describe a large outbreak involving a
Klebsiella pneumoniae
strain producing a plasmid-encoded ACC-1 type AmpC β-lactamase in a hospital caring for patients with motor impairment. The epidemic strain was isolated from 57 patients in six wards between September 1999 and May 2003 and caused clinical infections in 19 patients.
Rapid Inversion of the Prevalences of Macrolide Resistance Phenotypes Paralleled by a Diversification of T and
emm
Types among
Streptococcus pyogenes
in Portugal
Authors: Silva-Costa C. , Ramirez M. , Melo-Cristino J.
Published: April 2005

In Portugal erythromycin resistance of 26.6% (
n
= 352) remained constant during 1998 to 2003, however in 1998 the MLS
B
phenotype dominated (85%), whereas in 2003 the M phenotype prevailed (77%). A decline in T12/
emm
22 MLS
B
isolates could partially explain the drop in this phenotype, but the rise of the M phenotype was not due to clonal expansion.
Nationwide Study of
Escherichia coli
and
Klebsiella pneumoniae
Producing Extended-Spectrum β-Lactamases in Spain
Authors: Hernández J. R. , Martínez-Martínez L. , Cantón R. , Coque T. M. , Pascual A.
Published: April 2005

Clonal dissemination of extended-spectrum β-lactamases (ESBL) in 170
Escherichia coli
isolates and 70
Klebsiella pneumoniae
isolates from a nationwide study of 40 Spanish centers in 2000 was not observed in most centers. The most prevalent ESBL were CTX-M-9 (27.3%), SHV-12 (23.9%), and CTX-M-14 (20.5%) for
E. coli
and TEM-3 (16.7%) and TEM-4 (25%) for
K. pneumoniae
. A new ESBL, TEM-133, with mutations L21F, E104K, and R164S, was identified.
Substrate-Dependent Utilization of OprM or OpmH by the
Pseudomonas aeruginosa
MexJK Efflux Pump
Authors: Chuanchuen Rungtip , Murata Takeshi , Gotoh Naomasa , Schweizer Herbert P.
Published: April 2005

MexJK requires OprM for erythromycin efflux but not for triclosan efflux. Deletion of 15 OprM family outer membrane proteins (OMPs) revealed that only the TolC homolog OpmH functions with MexJK for triclosan efflux. This is the first report of natural utilization of multiple OMPs by a given resistance nodulation cell division transporter/membrane fusion protein pair.
High Levels of Antimicrobial Coresistance among Extended-Spectrum-β-Lactamase-Producing
Enterobacteriaceae
Authors: Schwaber Mitchell J. , Navon-Venezia Shiri , Schwartz David , Carmeli Yehuda
Published: April 2005

We compared the susceptibility of 312 extended-spectrum β-lactamase (ESBL)-producing
Enterobacteriaceae
isolates with that of 1,216 ESBL nonproducers. Of ESBL producers, 25% were susceptible to gentamicin, 30% to trimethoprim-sulfamethoxazole, 41% to ciprofloxacin, and 60% to piperacillin-tazobactam. ESBL nonproducers were more often susceptible to these agents. ESBL-producing
Enterobacteriaceae
represent a major source of resistance to various antibiotics.
RELATIVISTIC MODEL OF DETONATION TRANSITION FROM NEUTRON TO STRANGE MATTER
Authors: TOKAREVA I. , NUSSER A. , GUROVICH V. , FOLOMEEV V.
Published: April 2005

We study the conversion of neutron matter into strange matter as a detonation wave. The detonation is assumed to originate from a central region in a spherically symmetric background of neutrons with a varying radial density distribution. We present self-similar solutions for the propagation of detonation in static and collapsing backgrounds of neutron matter. The solutions are obtained in the framework of general relativistic hydrodynamics, and are relevant for the possible transition of neutron into strange stars. Conditions for the formation of either bare or crusted strange stars are discussed.
EMERGENCE OF A FILAMENTARY STRUCTURE IN THE FIREBALL FROM GRB SPECTRA
Authors: RUFFINI REMO , BIANCO CARLO LUCIANO , XUE SHE-SHENG , CHARDONNET PASCAL , FRASCHETTI FEDERICO , GURZADYAN VAHE
Published: April 2005

It is shown that the concept of a fireball with a definite filamentary structure naturally emerges from the analysis of the spectra of Gamma-Ray Bursts (GRBs). These results, made possible by the recently obtained analytic expressions of the equitemporal surfaces in the GRB afterglow, depend crucially on the single parameter ℛ describing the effective area of the fireball emitting the X-ray and gamma-ray radiation. The X-ray and gamma-ray components of the afterglow radiation are shown to have a thermal spectrum in the co-moving frame of the fireball and originate from a stable shock front described self-consistently by the Rankine–Hugoniot equations. Precise predictions are presented on a correlation between spectral changes and intensity variations in the prompt radiation verifiable, e.g., by the Swift and future missions. The highly variable optical and radio emission depends instead on the parameters of the surrounding medium. The GRB 991216 is used as a prototype for this model.
RECOVERY OF A SURFACE WITH BOUNDARY AND ITS CONTINUITY AS A FUNCTION OF ITS TWO FUNDAMENTAL FORMS
Authors: CIARLET PHILIPPE G. , MARDARE CRISTINEL
Published: April 2005

If a field A of class [Formula: see text] of positive-definite symmetric matrices of order two and a field B of class [Formula: see text] of symmetric matrices of order two satisfy together the Gauss and Codazzi–Mainardi equations in a connected and simply-connected open subset ω of ℝ2, then there exists an immersion [Formula: see text], uniquely determined up to proper isometries in ℝ3, such that A and B are the first and second fundamental forms of the surface θ(ω). Let [Formula: see text] denote the equivalence class of θ modulo proper isometries in ℝ3 and let [Formula: see text] denote the mapping determined in this fashion.

The first objective of this paper is to show that, if ω satisfies a certain "geodesic property" (in effect a mild regularity assumption on the boundary of ω) and if the fields A and B and their partial derivatives of order ≤ 2 (respectively, ≤ 1), have continuous extensions to [Formula: see text], the extension of the field A remaining positive-definite on [Formula: see text], then the immersion θ and its partial derivatives of order ≤ 3 also have continuous extensions to [Formula: see text].

The second objective is to show that, if ω satisfies the geodesic property and is bounded, the mapping ℱ can be extended to a mapping that is locally Lipschitz-continuous with respect to the topologies of the Banach spaces [Formula: see text] for the continuous extensions of the matrix fields (A, B), and [Formula: see text] for the continuous extensions of the immersions θ.
ON THE RECOVERY AND CONTINUITY OF A SUBMANIFOLD WITH BOUNDARY
Authors: SZOPOS MARCELA
Published: April 2005

The fundamental theorem of Riemannian geometry asserts that a connected and simply-connected Riemannian space ω of ℝp can be isometrically immersed into the Euclidean space ℝp+q if and only if there exist tensors satisfying the Gauss–Ricci–Codazzi equations, in which case these immersions are uniquely determined up to isometries in ℝp+q. In this fashion, we can define a mapping which associates with these prescribed tensors the reconstructed submanifold. The purpose of this paper is twofold: under a smoothness assumption on the boundary of ω, we first establish an analogous result for the existence and uniqueness of a submanifold "with boundary" and then show that the mapping constructed in this fashion is locally Lipschitz-continuous with respect to the topology of the Banach spaces [Formula: see text].
GLOBAL SOLUTIONS TO THE BOLTZMANN EQUATION WITH EXTERNAL FORCES
Authors: UKAI SEIJI , YANG TONG , ZHAO HUIJIANG
Published: April 2005

For the Boltzmann equation with an external potential force depending only on the space variables, there is a family of stationary solutions, which are local Maxwellians with space dependent density, zero velocity and constant temperature. In this paper, we will study the nonlinear stability of these stationary solutions by using the energy method. The analysis combines the analytic techniques used for the conservation laws using the fluid-type system derived from the Boltzmann equation (cf. [14]) and the dissipative effects on the fluid and non-fluid components of the Boltzmann equation through the celebrated H-theorem. To our knowledge, this is the first result on the global classical solutions to the Boltzmann equation with external force and non-trivial large time behavior in the whole space.
TRADE-OFFS IN DETECTING EVOLUTIONARILY CONSTRAINED SEQUENCE BY COMPARATIVE GENOMICS
Authors: Stone Eric A. , Cooper Gregory M. , Sidow Arend
Published: April 2005

▪ Abstract  As whole-genome sequencing efforts extend beyond more traditional model organisms to include a deep diversity of species, comparative genomic analyses will be further empowered to reveal insights into the human genome and its evolution. The discovery and annotation of functional genomic elements is a necessary step toward a detailed understanding of our biology, and sequence comparisons have proven to be an integral tool for that task. This review is structured to broadly reflect the statistical challenges in discriminating these functional elements from the bulk of the genome that has evolved neutrally. Specifically, we review the comparative genomics literature in terms of specificity, sensitivity, and phylogenetic scope, as well as the trade-offs that relate these factors in standard analyses. We consider the impact of an expanding diversity of orthologous sequences on our ability to resolve functional elements. This impact is assessed through both recent comparative analyses of deep alignments and mathematical modeling.
YERSINIA OUTER PROTEINS: Role in Modulation of Host Cell Signaling Responses and Pathogenesis
Authors: Viboud Gloria I. , Bliska James B.
Published: April 2005

A type III secretion system (TTSS) is encoded on a virulence plasmid that is common to three pathogenic Yersinia species: Y. enterocolitica, Y. pseudotuberculosis, and Y. pestis. Pathogenic Yersinia species require this TTSS to survive and replicate within lymphoid tissues of their animal or human hosts. A set of pathogenicity factors, including those known as Yersinia outer proteins (Yops), is exported by this system upon bacterial infection of host cells. Two translocator Yops (YopB and YopD) insert into the host plasma membrane and function to transport six effector Yops (YopO, YopH, YopM, YopT, YopJ, and YopE) into the cytosol of the host cell. Effector Yops function to counteract multiple signaling responses in the infected host cell. The signaling responses counteracted by Yops are initiated by phagocytic receptors, Toll-like receptors, translocator Yops, and additional mechanisms. Innate and adaptive immune responses are thwarted as a consequence of Yop activities. A biochemical function for each effector Yop has been established, and the importance of these proteins for the pathogenesis process is being elucidated. This review focuses on the biochemical functions of Yops, the signaling pathways they modulate, and the role of these proteins in Yersinia virulence.
DIVERSITY AND EVOLUTION OF PROTEIN TRANSLOCATION
Authors: Pohlschröder Mechthild , Hartmann Enno , Hand Nicholas J. , Dilks Kieran , Haddad Alex
Published: April 2005

Cells need to translocate proteins into and across hydrophobic membranes in order to interact with the extracellular environment. Although a subset of proteins are thought to spontaneously insert into lipid bilayers, translocation of most transported proteins requires additional cellular components. Such components catalyze efficient lateral transport into or across cellular membranes in prokaryotes and eukaryotes. These include, among others, the conserved YidC/Oxa1/Alb3 proteins as well as components of the Sec and the Tat pathways. Our current knowledge of the function and distribution of these components and their corresponding pathways in organisms of the three domains of life is reviewed. On the basis of this information, the evolution of protein translocation is discussed.
DEFECTIVE GLUCOSE HOMEOSTASIS DURING INFECTION
Authors: McGuinness Owen P.
Published: April 2005

▪ Abstract  Infection leads to profound alterations in whole-body metabolism, which is characterized by marked acceleration of glucose, fat and protein, and amino acid flux. One of the complications of infection, especially in the nutritionally supported setting, is hyperglycemia. The hyperglycemia is caused by peripheral insulin resistance and alterations in hepatic glucose metabolism. The defects in hepatic glucose metabolism include overproduction of glucose and a failure of the liver to appropriately adapt when nutritional support is administered. Investigators have suggested that multiple factors contribute to the observed defects. In this review, I focus primarily on alterations in carbohydrate metabolism, examining both the metabolic response to infection and inflammatory stress, the role of the accompanying neuroendocrine and inflammatory responses in the metabolic response, and the interaction between the endocrine response to infection and nutritional support.
Substrate size as a determinant of fibrillatory activity maintenance in a mathematical model of canine atrium
Authors: Zou Renqiang , Kneller James , Leon L. Joshua , Nattel Stanley
Published: April 2005

Tissue size has been considered an important determinant of atrial fibrillation (AF), but recent work has questioned the critical size hypothesis. Here, we use a previously developed mathematical model of the two-dimensional canine atrium with realistic action potential, ionic, and conduction properties to address substrate size effects on the maintenance of fibrillatory activity. Cholinergic AF was simulated at different acetylcholine (ACh) concentrations ([ACh]) and distributions, with substrate area varied 11.1-fold. Automated phase singularity detection was used to facilitate the analysis of arrhythmic activity. The duration of activity induced by a single extrastimulus increased with increasing substrate dimensions. Two general mechanisms underlying activity were observed and were differentially affected by substrate size. For large mean [ACh], single primary rotors anchored in low-[ACh] zones maintained activity and substrate dimensions were not critical. At lower mean [ACh], extensive spiral wave meander prevented the emergence of single stable rotors. Prolonged activity was favored when substrate size permitted a sufficiently large number of simultaneous longer-lasting rotors that extinction of all was unlikely. Thus either single dominant rotor or multiple reentrant spiral generator mechanisms could maintain fibrillatory activity in this model and were differentially dependent on substrate size. These results speak to recent debates about the role in AF of single driver rotors versus multiple reentrant circuit mechanisms by suggesting that either may maintain fibrillatory atrial activity depending on atrial size and electrophysiological properties.
PKA delivery to the distal lung air spaces increases alveolar liquid clearance after isoproterenol-induced alveolar epithelial PKA desensitization
Authors: Maron Michael B. , Folkesson Hans G. , Stader Sonya M. , Walro Jon M.
Published: April 2005

Isoproterenol (Iso) infusion for 48 h in rats decreases the ability of β-adrenoceptor (β-AR) agonists to increase alveolar liquid clearance (ALC). An impairment in protein kinase A (PKA) function appears to be critical in producing the desensitized ALC response. To test this hypothesis, we used a novel protein delivery reagent (Chariot, Active Motif) to deliver either the PKA catalytic subunit or the PKA holoenzyme to the distal lung epithelium of Iso-infused rats (400 μg·kg−1·h−1, 48 h). After this infusion, ALC was measured by mass balance over 2 h. ALC in Iso-infused rats was 27.9% (SD 5.8) of instilled volume absorbed. Delivery of the catalytic PKA subunit to Iso-infused rats increased ALC to 47.7% (SD 8.9) ( P < 0.05). ALC in Iso-infused rats delivered the inactive PKA holoenzyme [29.6% (SD 2.5)] was not increased above baseline values. Subsequent holoenzyme activation by intravenous infusion of the stable cAMP analog Sp-8-Bromo-cAMPS increased ALC to 41.7% (SD 8.8) ( P < 0.05). Immunohistochemical localization of Chariot-delivered PKA revealed staining in the alveolar and distal airway epithelium. These data indicate that protein delivery reagents can be used to rapidly deliver biologically active proteins to the distal lung epithelium and that PKA desensitization may be an important rate-limiting event in the development of Iso-induced desensitization of the alveolar epithelial β-AR signaling pathway.
Scavenger receptor class A type I/II (CD204) null mice fail to develop fibrosis following silica exposure
Authors: Beamer Celine A. , Holian Andrij
Published: April 2005

Alveolar macrophages express the class A scavenger receptor (CD204) (Babaev VR, Gleaves LA, Carter KJ, Suzuki H, Kodama T, Fazio S, and Linton MF. Arterioscler Thromb Vasc Biol 20: 2593–2599, 2000); yet its role in vivo in lung defense against environmental particles has not been clearly defined. In the current study, CD204 null mice (129Sv background) were used to investigate the link between CD204 and downstream events of inflammation and fibrosis following silica exposure in vivo. CD204−/− macrophages were shown to recognize and uptake silica in vitro, although this response was attenuated compared with 129Sv wild-type mice. The production of tumor necrosis factor-α in lavage fluid was significantly enhanced in CD204 null mice compared with wild-type mice following silica exposure. Moreover, after exposure to environmental particles, CD204−/− macrophages exhibited improved cell viability in a dose-dependent manner compared with wild-type macrophages. Finally, histopathology from a murine model of chronic silicosis in 129Sv wild-type mice displayed typical focal lesions, interstitial thickening with increased connective tissue matrix, and cellular infiltrate into air space. In contrast, CD204−/− mice exhibited little to no deposition of collagen, yet they demonstrated enhanced accumulation of inflammatory cells largely composed of neutrophils. Our findings point to an important role of CD204 in mounting an efficient and appropriately regulated immune response against inhaled particles. Furthermore, these results indicate that the functions of CD204 are critical to the development of fibrosis and the resolution of inflammation.
Coexpression of RTI40 with alveolar epithelial type II cell proteins in lungs following injury: identification of alveolar intermediate cell types
Authors: Clegg Gareth R. , Tyrrell Christine , McKechnie Stuart R. , Beers Michael F. , Harrison David , McElroy Mary C.
Published: April 2005

Injured alveolar epithelial type (AT) I cells are replaced following the proliferation and transformation of ATII cells to new ATI cells. RTI40 is an ATI cell-specific protein required for normal lung development. We hypothesized that intermediate cell types in the ATII-to-ATI cell transformation would coexpress RTI40 and ATII cell-selective proteins. To test this hypothesis, we used a rat model of Staphylococcus aureus-induced acute lung injury and a panel of ATI and ATII cell-specific and -selective antibodies. S. aureus induced an acute inflammatory reaction that was resolving by day 3 postinoculation. At day 3 postinoculation, the alveolar wall was thickened secondary to ATII cell hyperplasia. With the use of confocal microscopy, there was a fivefold increase in the fractional surface area of alveolar walls stained with ATII cell membrane proteins (RTII70 and MMC4) and a decrease in the fractional surface area associated with RTI40-expressing cells. S. aureus-treated lungs also contained unique cell types that coexpressed the RTI40 and ATII markers RTI40/MMC4/RTII70- and RTI40/MMC4-positive cells. These cells were not observed in control lungs. RTI40/MMC4-positive cells were also found in cultured ATII cells before they transformed to an ATI-like phenotype. Our data suggest that RTI40/MMC4/RTII70- and RTI40/MMC4-positive cells are intermediates in the ATII-to-ATI cell transformation. These data also suggest that the coexpression of RTI40 with ATII cell proteins may be used to identify and investigate ATII cell transdifferentiation to ATI cells following injury.