bluuebunny/crossref_metadata_2025_split huggingface dataset:
Probabilistic Inspection Planning of the Åsgard A FPSO Hull Structure
With Respect to Fatigue
Authors: Lotsberg Inge , Sigurdsson Gudfinnur , Wold Per Terje 
Published: July 2002

Abstract
Probabilistic methods has been used to develop a basis for an in-service inspection program for the Åsgard A FPSO hull structure with respect to fatigue cracks. Åsgard A is a floating production unit constructed for Statoil and was installed on the Åsgard Field during the winter 1999. Hot spot areas showing the shortest calculated fatigue lives have been selected for probabilistic analyses. This implies areas at doubling plates and transverse stiffeners in the deck structure and the connections between the side longitudinals and the transverse frames. In FPSOs, there are a number of details with similar geometry that also are fabricated in the same way. Some of the details like those in the deck structure are also subjected to the same magnitude of loading. Consequently, there will be correlation in fatigue life when several components are considered at the same time. The effect of this correlation has been investigated for components that have a welded surface and components that are ground. A number of analyses have been performed to investigate the effect of this correlation on required amount of in-service inspection. And it is shown how results from these analyses are transferred into an in-service inspection program for the Åsgard A FPSO. [S0892-7219(00)00302-2]
Evaluation of Rifalazil in a Combination Treatment Regimen as an Alternative to Isoniazid-Rifampin Therapy in a Mouse Tuberculosis Model
Authors: Lenaerts Anne M. , Chase Sharon E. , Cynamon Michael H. 
Published: July 2002

ABSTRACT

The newer rifamycin, rifalazil (RLZ) (previously known as KRM-1648), has been shown in prior experiments to be a highly potent drug against
Mycobacterium tuberculosis
. In this report, we studied the efficacy of RLZ in combination with pyrazinamide (PZA) and ethambutol (EMB) in a long-term in vivo experiment and compared their activity with the isoniazid (INH)-rifampin (RIF) combination which is presently used in the clinic. Combinations of RLZ with PZA alone or with both PZA and EMB were both found to have sterilizing activities comparable to that of the INH-RIF combination but significantly better activity with respect to relapse of infection. These results suggest that RLZ, or other agents with similar activity, could be combined with available agents to act as a potential alternative drug regimen to the currently used INH-RIF combination.
Identification of a Cyclase Gene Dictating the C-9 Stereochemistry of Anthracyclines from
Streptomyces nogalater
Authors: Torkkell Sirke , Kunnari Tero , Palmu Kaisa , Hakala Juha , Mäntsälä Pekka , Ylihonko Kristiina 
Published: July 2002

ABSTRACT

Nogalamycin is an anthracycline antibiotic produced by
Streptomyces nogalater
. Its aglycone has a unique stereochemistry (7S, 9S, 10R) compared to that of most other anthracyclines (7S, 9R, 10R). The gene
sno
aL, encoding a nogalonic acid methyl ester cyclase for nogalamycin, was used to generate nogalamycinone, demonstrating that the single cyclase dictates the C-9 stereochemistry of anthracyclines.
Biochemical Sequence Analyses of GES-1, a Novel Class A Extended-Spectrum β-Lactamase, and the Class 1 Integron In52 from
Klebsiella pneumoniae
Authors: Poirel Laurent , Le Thomas Isabelle , Naas Thierry , Karim Amal , Nordmann Patrice 
Published: July 2002

ABSTRACT

Klebsiella pneumoniae
ORI-1 was isolated in 1998 in France from a rectal swab of a 1-month-old girl who was previously hospitalized in Cayenne Hospital, Cayenne, French Guiana. This strain harbored a ca. 140-kb nontransferable plasmid, pTK1, that conferred an extended-spectrum cephalosporin resistance profile antagonized by the addition of clavulanic acid, tazobactam, or imipenem. The gene for GES-1 (Guiana extended-spectrum β-lactamase) was cloned, and its protein was expressed in
Escherichia coli
DH10B, where this pI-5.8 β-lactamase of a ca. 31-kDa molecular mass conferred resistance to oxyimino cephalosporins (mostly to ceftazidime). GES-1 is weakly related to the other plasmid-located Ambler class A extended-spectrum β-lactamases (ESBLs). The highest percentage of amino acid identity was obtained with the carbenicillinase GN79 from
Proteus mirabilis
; with YENT, a chromosome-borne penicillinase from
Yersinia enterocolitica
; and with L-2, a chromosome-borne class A cephalosporinase from
Stenotrophomonas maltophilia
(36% amino acid identity each). However, a dendrogram analysis showed that GES-1 clustered within a class A ESBL subgroup together with ESBLs VEB-1 and PER-1. Sequencing of a 7,098-bp DNA fragment from plasmid pTK1 revealed that the GES-1 gene was located on a novel class 1 integron named In52 that was characterized by (i) a 5′ conserved segment containing an
intI1
gene possessing two putative promoters, P
1
and P
2
, for coordinated expression of the downstream antibiotic resistance genes and an
attI1
recombination site; (ii) five antibiotic gene cassettes,
bla
GES-1
,
aac(6′)Ib
′ (gentamicin resistance and amikacin susceptibility),
dfrXVb
(trimethoprim resistance), a novel chloramphenicol resistance gene (
cmlA4
), and
aadA2
(streptomycin-spectinomycin resistance); and (iii) a 3′ conserved segment consisting of
qacEΔ1
and
sulI
. The
bla
GES-1
and
aadA2
gene cassettes were peculiar, since they lacked a typical 59-base element. This work identified the second class A ESBL gene of a non-TEM, non-SHV series which was located in the plasmid and integron, thus providing it additional means for its spread and its expression.
Evaluation of Rifalazil in Long-Term Treatment Regimens for Tuberculosis in Mice
Authors: Shoen Carolyn M. , Chase Sharon E. , DeStefano Michelle S. , Harpster Tami S. , Chmielewski Alex J. , Cynamon Michael H. 
Published: July 2002

ABSTRACT

Previous experiments with rifalazil (RLZ) (also known as KRM-1648) in combination with isoniazid (INH) demonstrated its potential for short-course treatment of
Mycobacterium tuberculosis
infection. In this study we investigated the minimum RLZ-INH treatment time required to eradicate
M. tuberculosis
in a murine model. RLZ-INH treatment for 6 weeks or longer led to a nonculturable state. Groups of mice treated in parallel were killed following an observation period to evaluate regrowth. RLZ-INH treatment for a minimum of 10 weeks was necessary to maintain a nonculturable state through the observation period. Pyrazinamide (PZA) was added to this regimen to determine whether the treatment duration could be further reduced. In this model, the addition of PZA did not shorten the duration of RLZ-INH treatment required to eradicate
M. tuberculosis
from mice. The addition of PZA reduced the number of mice in which regrowth occurred, although the reduction was not statistically significant.
Linezolid Therapy of Vancomycin-Resistant
Enterococcus faecium
Experimental Endocarditis
Authors: Patel Robin , Rouse Mark S. , Piper Kerryl E. , Steckelberg James M. 
Published: July 2002

ABSTRACT

We compared the activities of linezolid (25 mg/kg of body weight, administered intraperitoneally every 8 h) and of vancomycin (25 mg/kg of body weight, administered intraperitoneally every 8 h) in a rat model of
vanA
vancomycin-resistant
Enterococcus faecium
experimental endocarditis. Results were expressed as median log
10
CFU per gram of vegetation after 3 days of treatment. The median log
10
CFU per gram of vegetation was 10.1 among 7 untreated control animals, 10.2 among 9 vancomycin-treated animals, and 7.9 among 10 linezolid-treated animals. Linezolid treatment was more active (
P
< 0.05) than vancomycin treatment or no treatment.
Pharmacokinetics of Clinafloxacin after Single and Multiple Doses
Authors: Randinitis Edward J. , Brodfuehrer Joanne I. , Eiseman Irene , Vassos Artemios B. 
Published: July 2002

ABSTRACTClinafloxacin (CI-960) is a potent broad-spectrum, fluoroquinolone antibiotic that has been studied for parenteral and oral administration in patients with serious infections. The objectives of these studies were to examine the pharmacokinetics and safety of clinafloxacin following administration of single and twice-daily intravenous (i.v.) and oral doses to volunteers. Plasma and urine samples were assayed by validated liquid chromatographic methods, and pharmacokinetic parameter values were determined by noncompartmental methods. Safety was evaluated by clinical observation and laboratory tests. Absorption was rapid after oral administration, with maximum concentrations in plasma (Cmax) generally occurring within 2 h. Concentrations in plasma declined biexponentially, with an average terminal half-life of 4 to 6 h after single doses and 5 to 7 h after multiple doses. Increases inCmaxand area under the concentration-time curves (AUC) were generally proportional to the dose. The volume of distribution was much greater than total body water. Approximately 40 to 75% of the clinafloxacin doses were excreted unchanged into urine. Absolute bioavailability of orally administered clinafloxacin was approximately 90% and did not change with increasing dose. Therefore, switching patients from i.v. to oral dosing should achieve similar concentrations in plasma. The tolerability of clinafloxacin was acceptable. No serious adverse events occurred.Cmaxvalues and minimum plasma clinafloxacin concentrations during multiple dosing exceeded MICs for a wide range of organisms.
A Novel Selenite- and Tellurite-Inducible Gene in
Escherichia coli
Authors: Guzzo Julie , Dubow Michael S. 
Published: July 2002

ABSTRACT

Selenium is both an essential and a toxic trace element, and the range of concentrations between the two is extremely narrow. Although tellurium is not essential and is only rarely found in the environment, it is considered to be extremely toxic. Several hypotheses have been proposed to account for the toxic effects of selenite and tellurite. However, these potential mechanisms have yet to be fully substantiated. Through screening of an
Escherichia coli luxAB
transcriptional gene fusion library, we identified a clone whose luminescence increased in the presence of increasing concentrations of sodium selenite or sodium tellurite. Cloning and sequencing of the
luxAB
junction revealed that the fusion had occurred in a previously uncharacterized open reading frame, termed
o393
or
yhfC
, which we have now designated
gutS
, for gene up-regulated by tellurite and selenite. Transcription from
gutS
in the presence of selenite or tellurite was confirmed by RNA dot blot analysis. In vivo expression of the GutS polypeptide, using the pET expression system, revealed a polypeptide of approximately 43 kDa, in good agreement with its predicted molecular mass. Although the function of GutS remains to be elucidated, homology searches as well as protein motif and secondary-structure analyses have provided clues which may implicate GutS in transport in response to selenite and tellurite.
Natural Mediators in the Oxidation of Polycyclic Aromatic Hydrocarbons by Laccase Mediator Systems
Authors: Johannes Christian , Majcherczyk Andrzej 
Published: July 2002

ABSTRACT

The oxidation of polycyclic aromatic compounds was studied in systems consisting of laccase from
Trametes versicolor
and so-called mediator compounds. The enzymatic oxidation of acenaphthene, acenaphthylene, anthracene, and fluorene was mediated by various laccase substrates (phenols and aromatic amines) or compounds produced and secreted by white rot fungi. The best natural mediators, such as phenol, aniline, 4-hydroxybenzoic acid, and 4-hydroxybenzyl alcohol were as efficient as the previously described synthetic compounds ABTS [2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)] and 1-hydroxybenzotriazole. The oxidation efficiency increased proportionally with the redox potentials of the phenolic mediators up to a maximum value of 0.9 V and decreased thereafter with redox potentials exceeding this value. Natural compounds such as methionine, cysteine, and reduced glutathione, containing sulfhydryl groups, were also active as mediator compounds.
16S rRNA Gene-Based Detection of Tetrachloroethene-DechlorinatingDesulfuromonasandDehalococcoidesSpecies
Authors: Löffler Frank E. , Sun Qing , Li Jieran , Tiedje James M. 
Published: July 2002

ABSTRACTMembers of the generaDesulfuromonasandDehalococcoidesreductively dechlorinate tetrachloroethene (PCE) and trichloroethene. Two primer pairs specific to hypervariable regions of the 16S rRNA genes of theDehalococcoidesgroup (comprisingDehalococcoides ethenogenesandDehalococcoidessp. strain FL2) and the acetate-oxidizing, PCE-dechlorinatingDesulfuromonasgroup (comprisingDesulfuromonassp. strain BB1 andDesulfuromonas chloroethenica) were designed. The detection threshold of a nested PCR approach using universal bacterial primers followed by a second PCR with theDesulfuromonasdechlorinator-targeted primer pair was 1 × 103BB1 cells added per gram (wet weight) of sandy aquifer material. Total community DNA isolated from sediments of three Michigan rivers and six different chloroethene-contaminated aquifer samples was used as template in nested PCR. All river sediment samples yielded positive signals with the BB1- and theDehalococcoides-targeted primers. One chloroethene-contaminated aquifer tested positive with theDehalococcoides-targeted primers, and another contaminated aquifer tested positive with theDesulfuromonasdechlorinator-targeted primer pair. Restriction fragment analysis of the amplicons could discriminate strain BB1 from other knownDesulfuromonasspecies. Microcosm studies confirmed the presence of PCE-dechlorinating, acetate-oxidizingDesulfuromonasand hydrogenotrophicDehalococcoidesspecies in samples yielding positive PCR signals with the specific primers.
Use of an Enzyme-Linked Lectinsorbent Assay To Monitor the Shift in Polysaccharide Composition in Bacterial Biofilms
Authors: Leriche V. , Sibille P. , Carpentier B. 
Published: July 2002

ABSTRACT

An enzyme-linked lectinsorbent assay (ELLA) was developed for quantification and characterization of extracellular polysaccharides produced by 1- and 4-day biofilms of 10 bacterial strains isolated from food industry premises. Peroxidase-labeled concanavalin A (ConA) and wheat germ agglutinin (WGA) were used, as they specifically bind to saccharide residues most frequently encountered in biofilms matrices:
d
-glucose or
d
-mannose for ConA and
N
-acetyl-
d
-glucosamine or
N
-acetylneuraminic acid for WGA. The ELLA applied to 1- and 4-day biofilms colonizing wells of microtiter plates was able to detect that for
Stenotrophomonas maltophilia
and to a lesser extent
Staphylococcus sciuri
, the increase in production of exopolysaccharides over time was not the same for sugars binding with ConA and those binding with WGA. Differences in extracellular polysaccharides produced were observed among strains belonging to the same species. These results demonstrate that ELLA is a useful tool not only for rapid characterization of biofilm extracellular polysaccharides but also, in studies of individual strains, for detection of changes over time in the proportion of the exopolysaccharidic component within the polymeric matrix.
Method for Host-Independent Detection of Generalized Transducing Bacteriophages in Natural Habitats
Authors: Sander Michaela , Schmieger Horst 
Published: July 2002

ABSTRACT

Despite an increasing interest in horizontal gene transfer in bacteria, the role of generalized transduction in this process has not been well investigated yet. Certainly one of the reasons is that only a small fraction of general transducing bacteriophages have been characterized, because many bacterial hosts needed for propagation and identification are not culturable or are simply unknown. A method for host-independent detection of transducing bacteriophages was developed. Phage-encapsulated DNA was used as a template for PCR amplification of 16S ribosomal DNA using primers specific for the 16S rRNA genes of most eubacteria. Sequencing of the cloned amplification products permits the identification of the host bacteria. The
Salmonella
phage P22 was used as an example. Applying this method to a sample of the supernatant of the mixed liquor in the aeration tank of an activated sludge treatment works revealed the presence of transducing phages infecting several bacterial species for which such phages have not yet been described. This method is suitable for estimating the contribution of generalized transduction to horizontal gene transfer in different habitats.
Low-Pressure UV Inactivation and DNA Repair Potential of
Cryptosporidium parvum
Oocysts
Authors: Shin Gwy-Am , Linden Karl G. , Arrowood Michael J. , Sobsey Mark D. 
Published: July 2002

ABSTRACT

Because
Cryptosporidium parvum
oocysts are very resistant to conventional water treatment processes, including chemical disinfection, we determined the kinetics and extent of their inactivation by monochromatic, low-pressure (LP), mercury vapor lamp UV radiation and their subsequent potential for DNA repair of UV damage. A UV collimated-beam apparatus was used to expose suspensions of purified
C. parvum
oocysts in phosphate-buffered saline, pH 7.3, at 25°C to various doses of monochromatic LP UV.
C. parvum
infectivity reductions were rapid, approximately first order, and at a dose of 3 mJ/cm
2
(=30 J/m
2
), the reduction reached the cell culture assay detection limit of ∼3 log
10
. At UV doses of 1.2 and 3 mJ/cm
2
, the log
10
reductions of
C. parvum
oocyst infectivity were not significantly different for control oocysts and those exposed to dark or light repair conditions for UV-induced DNA damage. These results indicate that
C. parvum
oocysts are very sensitive to inactivation by low doses of monochromatic LP UV radiation and that there is no phenotypic evidence of either light or dark repair of UV-induced DNA damage.
Serological Evaluation of Thin-Layer Immunoassay–Enzyme-Linked Immunosorbent Assay for Antibody Detection in Human Trichinellosis
Authors: Gómez-Priego Alberto , Crecencio-Rosales Lidia , de-la-Rosa Jorge-Luis 
Published: July 2002

ABSTRACT

A new immunoenzymatic test, named the thin-layer immunoassay–enzyme-linked immunosorbent assay (TIA-ELISA), was evaluated for antibody detection in human trichinellosis using excretion and secretion products prepared from
Trichinella spiralis
muscle larvae. Serum samples from people with positive muscle biopsies or symptoms compatible with the disease (
n
= 8 or 26, respectively), all reactive in enzyme-linked immunoelectrotransfer blot assay (EITB), as well as 67 serum samples from healthy, EITB-negative people, were tested in an ELISA and TIA-ELISA. TIA-ELISA was performed in polystyrene plastic petri dishes by adding dots of 10 μl each of antigen (7 μg/ml) followed by adding diluted serum and the conjugate. Finally, the substrate mixed with agar was added to develop the reaction. Enzymatic by-products were easily detected by the naked eye as defined dots. Sensitivity and specificity were 76 and 94% for ELISA, and both parameters were 91% for TIA-ELISA. The kappa correlation indices for both tests in relation to EITB were 0.73 and 0.80, respectively. The TIA-ELISA can be carried out with common laboratory equipment in 3 h and uses lower quantities of antigen than EITB and ELISA. Since TIA-ELISA is easy to perform, cheap, sensitive, and specific, the test could be an acceptable alternative to use in clinical laboratories lacking specialized equipment needed for ELISA and EITB and in field studies for antibody detection in human trichinellosis.
Significant Role of Interleukin-8 in Pathogenesis of Pulmonary Disease Due to
Mycoplasma pneumoniae
Infection
Authors: Narita Mitsuo , Tanaka Hiroshi , Yamada Satoshi , Abe Shosaku , Ariga Tadashi , Sakiyama Yukio 
Published: July 2002

ABSTRACT

We found elevated levels of interleukin-8 in pleural fluid samples from patients with pleural effusion and with a sustained fibrotic change of the lung due to
Mycoplasma pneumoniae
infection. This result suggests a critical role of interleukin-8 in the pathogenesis of a certain type of pulmonary disease caused by
M. pneumoniae
.
Opsonophagocytosis of Fluorescent Polystyrene Beads Coupled to
Neisseria meningitidis
Serogroup A, C, Y, or W135 Polysaccharide Correlates with Serum Bactericidal Activity
Authors: Martinez Joseph , Pilishvili Tamara , Barnard Suzanne , Caba Joseph , Spear Willie , Romero-Steiner Sandra , Carlone George M. 
Published: July 2002

ABSTRACT

We developed a polysaccharide-specific flow cytometric opsonophagocytic assay (OPA) for the simultaneous measurement of functional antibody to
Neisseria meningitidis
serogroups A, C, Y, and W135. OPA titers significantly correlated with serum bactericidal assay titers for all serogroups tested (mean
r
= 0.96;
P
< 0.001). OPA could be used in meningococcal vaccine evaluation.
Importance of M-Protein C Terminus as Substrate Antigen for Serodetection of Equine Arteritis Virus Infection
Authors: Jeronimo Célia , Archambault Denis 
Published: July 2002

ABSTRACT

Equine arteritis virus (EAV), an enveloped positive-stranded RNA virus, is the prototype of the arterivirus group. In a previous paper (A. Kheyar, S. Martin, G. St.-Laurent, P. J. Timoney, W. H. McCollum, and D. Archambault, Clin. Diagn. Lab. Immunol. 4:648-652, 1997), we have shown that the unglycosylated membrane (M) protein, which is composed of 162 amino acids (aa), is a major target of equine antibody to EAV. In order to determine the antigenic regions of the M protein, the cDNA encoding the M protein of EAV was inserted into the procaryotic expression vector pGEX-4T-1 to produce recombinant glutathione
S
-transferase-M fusion protein. Various deletion mutant clones, which covered the entire sequence of the M protein, were then generated by inverse PCR and expressed in
Escherichia coli
to examine, by a Western blot assay, the antigenic reactivity of the clone-derived truncated M proteins with sera from horses either experimentally or naturally infected with EAV. Deletion of the hydrophobic N-terminal 87 aa did not abolish immune reactivity of the protein with serum antibodies to EAV, thereby demonstrating the antigenicity of the C-terminal region (aa 88 to 162) of the M protein. Further truncations of the M-protein C-terminal domain defined particular linear epitope-containing amino acid sequence regions. However, only the M-protein C-terminal region was readily recognized by all EAV-specific horse antisera tested in this study. Based on these findings, only the M-protein C-terminal polypeptide composed of aa 88 to 162 is necessary to identify horse serum antibodies specific to the EAV M protein. Thus, this polypeptide might be useful for serodetection of EAV-infected animals.
Cytotoxic Cell Vacuolating Activity from
Vibrio cholerae
Hemolysin
Authors: Coelho Ana , Andrade João R. C. , Vicente Ana Carolina P. , Dirita Victor J. 
Published: July 2002

ABSTRACT

A
Vibrio cholerae
cytotoxin, designated VcVac, was found to cause vacuolation in Vero cells. It was originally detected in the pathogenic O1 Amazonia variant of
V. cholerae
and later shown to be produced in environmental strains and some El Tor strains. Comparison of VcVac production in various strains suggested that hemolysin was responsible for the vacuolating phenotype. Genetic experiments established a firm correlation between vacuolation and hemolysin production. The mammalian cell vacuolating activity of the
V. cholerae
hemolysin is a new property of this protein and points to a previously unknown type of interaction between
V. cholerae
and its host.