bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Two Densities of Caged Monosex Nile Tilapia, Oreochromis niloticus, on Water Quality, Phytoplankton Populations, and Production When Polycultured with Macrobrachium rosenbergii in Temperate Ponds
Authors: Danaher Jason J. , Tidwell James H. , Coyle Shawn D. , Dasgupta Siddhartha , Zimba Paul V. 
Published: August 2007

Abstract The effects of different densities of caged Nile tilapia, Oreochromis niloticus, on water quality, phytoplankton populations, prawn, and total pond production were evaluated in freshwater prawn, Macrobrachium rosenbergii, production ponds. The experiment consisted of three treatments with three 0.04‐ha replicates each. All ponds were stocked with graded, nursed juvenile prawn (0.9 ± 0.6 g) at 69,000/ha. Control (CTL) ponds contained only prawns. Low‐density polyculture (LDP) ponds also contained two cages (1 m3; 100 fish/cage) of monosex male tilapia (115.6 ± 22 g), and high‐density polyculture (HDP) ponds had four cages. Total culture period was 106 d for tilapia and 114 d for prawn. Overall mean afternoon pH level was significantly lower (P ≤ 0.05) in polyculture ponds than in CTL ponds but did not differ (P > 0.05) between LDP and HDP. Phytoplankton biovolume was reduced in polyculture treatments. Tilapia in the LDP treatment had significantly higher (P ≤ 0.05) harvest weights than in the HDP treatment. Prawn weights were higher (P ≤ 0.05) in polyculture than prawn monoculture. These data indicate that a caged tilapia/freshwater prawn polyculture system may provide pH control while maximizing pond resources in temperate areas.
Growth of Tiger Puffer, Takifugu rubripes, at Different Salinities
Authors: Kikuchi Kotaro , Furuta Takeshi , Ishizuka Haruo , Yanagawa Toshiharu 
Published: August 2007

Abstract Two 12‐wk rearing experiments were conducted to examine the effect of rearing salinities of 10–35 ppt on the growth of 3‐ and 170‐g‐size tiger puffer, Takifugu rubripes. Fish were reared in a closed recirculation system without introducing fresh culture water at 23 C and were fed commercial pellet diet for tiger puffer twice or three times daily to apparent satiation each, almost everyday. Growth of 3‐g‐size fish seemed to increase with decreasing salinity; however, there were no significant differences in the specific growth rate and weight gain among treatments because of differences in initial body weight. Final body weight and length of fish reared at 10 ppt were significantly higher than those for fish reared at 30 ppt although initial sizes were similar. Differences were not found for the feed efficiency (FE) and daily feed consumption. Apparent relationships were not observed between salinity and blood characteristics or proximate compositions of muscle of the cultured fish. Differing from smaller fish, growth of 170‐g‐size fish tended to decrease with decreasing salinity from 30 to 10 ppt and with increasing salinity from 30 to 35 ppt. Similar trends for FE were observed.
Effect of Dietary Inclusion of N‐Acetyl Cysteine on Mucus Viscosity and Susceptibility of Rainbow Trout, Oncorhynchus mykiss, and Atlantic Salmon, Salmo salar, to Amoebic Gill Disease
Authors: Powell Mark D. , Ransome Julie , Barney Megan , Duijf Raymond M. M. , Flik Gert 
Published: August 2007

Abstract The treatment of amoebic gill disease (AGD) in cultured Atlantic salmon, Salmo salar L., using mucolytic agents has been previously reported. The agent L‐cysteine ethyl ester reduces salmonid mucus viscosity and potentially increases the flushing of the gill. In the present study, the effects of the mucolytic agent N‐acetyl cysteine (NAC) were assessed. Cutaneous mucus from rainbow trout, Oncorhynchus mykiss Walbaum, and Atlantic salmon was shown to have reduced viscosity when mixed in vitro with 100 or 200 μg/mL NAC. Saltwater‐acclimated rainbow trout and Atlantic salmon were fed an oil‐incorporated, NAC‐medicated diet (8 g NAC/kg diet) for up to 24 d and challenged with inoculation of 300 cells/L Neoparamoeba spp., the etiological agent of AGD. Control fish were fed normal oil‐coated pellets and received no NAC. NAC medication failed to reduce the severity of gill lesions associated with AGD even though the mucus viscosity from medicated fish was less than that of controls. Oral NAC medication does not appear to be an effective method for controlling AGD in salmonids despite reducing cutaneous mucus viscosity.
The application of Tet repressor in prokaryotic gene regulation and expression
Authors: Bertram Ralph , Hillen Wolfgang 
Published: August 2007

SummaryInducible gene expression based upon Tet repressor (tet regulation) is a broadly applied tool in molecular genetics. In its original environment, Tet repressor (TetR) negatively controls tetracycline (tc) resistance in bacteria. In the presence of tc, TetR is induced and detaches from its cognate DNA sequence tetO, so that a tc antiporter protein is expressed. In this article, we provide a comprehensive overview about tet regulation in bacteria and illustrate the parameters of different regulatory architectures. While some of these set‐ups rely on natural tet‐control regions like those found on transposon Tn10, highly efficient variations of this system have recently been adapted to different Gram‐negative and Gram‐positive bacteria. Novel tet‐controllable artificial or hybrid promoters were employed for target gene expression. They are controlled by regulators expressed at different levels either in a constitutive or in an autoregulated manner. The resulting tet systems have been used for various purposes. We discuss integrative elements vested with tc‐sensitive promoters, as well as tet regulation in Gram‐negative and Gram‐positive bacteria for analytical purposes and for protein overproduction. Also the use of TetR as an in vivo biosensor for tetracyclines or as a regulatory device in synthetic biology constructs is outlined. Technical specifications underlying different regulatory set‐ups are highlighted, and finally recent developments concerning variations of TetR are presented, which may expand the use of prokaryotic tet systems in the future.
Metabolic engineering to enhance bacterial hydrogen production
Authors: Maeda Toshinari , Sanchez‐Torres Viviana , Wood Thomas K. 
Published: August 2007

SummaryHydrogen fuel is renewable, efficient and clean, and fermentative bacteria hold great promise for its generation. Here we use the isogenic Escherichia coli K‐12 KEIO library to rapidly construct multiple, precise deletions in the E. coli genome to direct the metabolic flux towards hydrogen production. Escherichia coli has three active hydrogenases, and the genes involved in the regulation of the formate hydrogen lyase (FHL) system for synthesizing hydrogen from formate via hydrogenase 3 were also manipulated to enhance hydrogen production. Specifically, we altered regulation of FHL by controlling the regulators HycA and FhlA, removed hydrogen consumption by hydrogenases 1 and 2 via the hyaB and hybC mutations, and re‐directed formate metabolism using the fdnG, fdoG, narG, focA, fnr and focB mutations. The result was a 141‐fold increase in hydrogen production from formate to create a bacterium (BW25113 hyaB hybC hycA fdoG/pCA24N‐FhlA) that produces the largest amount of hydrogen to date and one that achieves the theoretical yield for hydrogen from formate. In addition, the hydrogen yield from glucose was increased by 50%, and there was threefold higher hydrogen production from glucose with this strain.
TG‐43U1 parameterization of elongated RadioCoil brachytherapy sources
Authors: Dini Sharifeh A. , Awan Shahid B. , Dou Kai , Meigooni Ali S. 
Published: August 2007

Recently, to eliminate problems associated with seed type sources, RadioMed Corporation (Tyngsboro, MA) introduced RadioCoil sources for interstitial prostate implants. The RadioCoil sources are available in integral lengths ranging from 1.0 cm to 6.0 cm. In this project, dosimetric characteristics of these sources were determined following the TG‐43U1 recommendations, with consideration of our recent publication on the evaluation of two‐dimensional anisotropy function for elongated brachytherapy sources. Dosimetric parameters of these sources were determined experimentally in Solid Water (Gammex RMI, Middleton, WI) and theoretically using Monte Carlo simulation in Solid Water and liquid water. Per the TG‐43U1 protocol, the consensus of these results would be used for their clinical applications.PACS number: 87.53.Jw
Comparative Immunogenicities of Frozen and Refrigerated Formulations of Live Attenuated Influenza Vaccine in Healthy Subjects
Authors: Block Stan L. , Reisinger Keith S. , Hultquist Micki , Walker Robert E. 
Published: August 2007

ABSTRACTThe frozen version of live attenuated influenza vaccine (LAIV; FluMist) was compared with a newly licensed, refrigerated formulation, the cold-adapted influenza vaccine, trivalent (CAIV-T), for their immunogenicity, safety, and tolerability in healthy subjects 5 to 49 years of age. Eligible subjects were randomized 1:1 to receive CAIV-T or frozen LAIV. Subjects 5 to 8 years of age received two doses of vaccine 46 to 60 days apart; subjects 9 to 49 years of age received one dose of vaccine. Equivalent immunogenicities were defined as serum hemagglutination inhibition (HAI) geometric mean titer (GMT) ratios >0.5 and <2.0 for each of the three vaccine-specific strains. A total of 376 subjects 5 to 8 years of age and 566 subjects 9 to 49 years of age were evaluable. Postvaccination HAI GMT ratios were equivalent for CAIV-T and LAIV. The GMT ratios of CAIV-T/LAIV for the H1N1, H3N2, and B strains were 1.24, 1.02, and 1.00, respectively, for the 5- to 8-year-old age group and 1.14, 1.12, and 0.96, respectively, for the 9- to 49-year-old age group. Seroresponse/seroconversion rates (fourfold or greater rise) were similar in both age groups for each of the three vaccine strains. Within 28 days, the most frequent reactogenicity event in the CAIV-T and LAIV groups was runny nose/nasal congestion, which occurred at higher rates after dose 1 (44% and 42%, respectively) than after dose 2 (41% and 29%, respectively) in the 5- to 8-year-old group. Otherwise, the rates of adverse events (AEs) were similar between the treatment groups and the two age cohorts, with no serious AEs related to the study vaccines. The immunogenicities, reactogenicity events, and AEs were comparable for refrigerated CAIV-T and frozen LAIV.
Mupirocin-Resistant, Methicillin-Resistant
Staphylococcus aureus
Strains in Canadian Hospitals
Authors: Simor Andrew E. , Stuart Tammy L. , Louie Lisa , Watt Christine , Ofner-Agostini Marianne , Gravel Denise , Mulvey Michael , Loeb Mark , McGeer Allison , Bryce Elizabeth , Matlow Anne 
Published: August 2007

ABSTRACT

Mupirocin resistance in
Staphylococcus aureus
is increasingly being reported in many parts of the world. This study describes the epidemiology and laboratory characterization of mupirocin-resistant methicillin-resistant
S. aureus
(MRSA) strains in Canadian hospitals. Broth microdilution susceptibility testing of 4,980 MRSA isolates obtained between 1995 and 2004 from 32 Canadian hospitals was done in accordance with CLSI guidelines. The clinical and epidemiologic characteristics of strains with high-level mupirocin resistance (HLMup
r
) were compared with those of mupirocin-susceptible (Mup
s
) strains. MRSA strains were characterized by pulsed-field gel electrophoresis (PFGE) and typing of the staphylococcal chromosomal cassette
mec
. PCR was done to detect the presence of the
mupA
gene. For strains with
mupA
, plasmid DNA was extracted and subjected to Southern blot hybridization. A total of 198 (4.0%) HLMup
r
MRSA isolates were identified. The proportion of MRSA strains with HLMup
r
increased from 1.6% in the first 5 years of surveillance (1995 to 1999) to 7.0% from 2000 to 2004 (
P
< 0.001). Patients with HLMup
r
MRSA strains were more likely to have been aboriginal (odds ratio [OR], 3.7; 95% confidence interval [CI], 1.5 to 9.4;
P
= 0.006), to have had community-associated MRSA (OR, 2.2; 95% CI, 1.0 to 5.0;
P
= 0.05), and to have been colonized with MRSA (OR, 1.7; 95% CI, 1.0 to 3.0;
P
= 0.04). HLMup
r
MRSA strains were also more likely to be resistant to fusidic acid (21% versus 4% for mupirocin-susceptible strains;
P
< 0.001). All HLMup
r
MRSA strains had a plasmid-associated
mupA
gene, most often associated with a 9-kb HindIII fragment. PFGE typing and analysis of the plasmid profiles indicate that both plasmid transmission and the clonal spread of HLMup
r
MRSA have occurred in Canadian hospitals. These results indicate that the incidence of HLMup
r
is increasing among Canadian strains of MRSA and that HLMup
r
MRSA is recovered from patients with distinct clinical and epidemiologic characteristics compared to the characteristics of patents with Mup
s
MRSA strains.
A Ser678Pro Substitution in Fks1p Confers Resistance to Echinocandin Drugs in
Aspergillus fumigatus
Authors: Rocha Eleusa Maria F. , Garcia-Effron Guillermo , Park Steven , Perlin David S. 
Published: August 2007

ABSTRACT

An S678P substitution in Fks1p, the major subunit of glucan synthase, was sufficient to confer echinocandin resistance in
Aspergillus fumigatus
. The equivalent mutation in
Candida
spp. has been implicated in echinocandin resistance. This work demonstrates that modification of Fks1p is a conserved mechanism for echinocandin resistance in pathogenic fungi.
An OXA-66/OXA-51-Like Carbapenemase and Possibly an Efflux Pump Are Associated with Resistance to Imipenem in
Acinetobacter baumannii
Authors: Hu Wensi S. , Yao Shu-Man , Fung Chang-Phone , Hsieh Yi-Ping , Liu Chang-Pan , Lin Jing-Fang 
Published: August 2007

ABSTRACT

We investigated the mechanisms involved in imipenem resistance in 23 clinical strains of
Acinetobacter baumannii
. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed the presence of a 30-kDa protein in imipenem-intermediate
A. baumannii
(IIAB) and imipenem-resistant
A. baumannii
(IRAB) strains; this protein was almost undetectable in imipenem-susceptible
A. baumannii
(ISAB) strains. The 30-kDa protein was identified as an OXA-51-like carbapenemase using two-dimensional gel electrophoresis and mass spectrometry. Similar to other recent findings,
bla
OXA-51-like
genes were found to exist in all 23 clinical strains; however, the transcript levels of
bla
OXA-51-like
in the IIAB and IRAB were higher than in the ISAB strains using reverse transcriptase PCR (RT-PCR) and real-time RT-PCR assays. This change was due to the presence of an insertion sequence, IS
Aba1
, upstream of
bla
OXA-51-like
in the IIAB and IRAB strains that was not present in the ISAB strains. The introduction of
bla
OXA-66
(a
bla
OXA-51
-like
gene), identified in ISAB ab1254 and IRAB ab1266, into
Escherichia coli
TOP10 cells resulted in 3.95-fold and 7.90-fold elevations in resistance to imipenem, respectively. Furthermore, when ISAB ab8 and ISAB ab1254 and their in vitro-selected imipenem-resistant mutants ISAB ab8(r) and ISAB ab1254(r) were compared, the results showed no change in the
bla
OXA-66
/
bla
OXA-51-like
gene sequences, in expression of the gene, and in the outer membrane protein profiles. However, there was a four- to eightfold reduction in imipenem resistance upon adding carbonyl cyanide
m
-chlorophenylhydrazone. Taken together, these results suggest that the OXA-66/OXA-51-like carbapenemase contributes to intrinsic resistance to imipenem; however, drug export by an efflux pump may be more important and/or occur more frequently in imipenem-resistant
A. baumannii
. Furthermore, this is the first report of a Taiwanese strain of an OXA-66/OXA-51-like carbapenemase that confers imipenem resistance in
A. baumannii
.
Construction and Characterization of Single-Chain Variable Fragment Antibodies Directed against the
Bordetella pertussis
Surface Adhesins Filamentous Hemagglutinin and Pertactin
Authors: Hussein Ahmad H. , Davis Elisabeth M. , Halperin Scott A. , Lee Song F. 
Published: August 2007

ABSTRACT

A single-chain variable fragment (scFv) antibody library against
Bordetella pertussis
was constructed using M13 phage display. The library was enriched for phages surface displaying functional scFv by biopanning against
B. pertussis
immobilized on polystyrene plates. Two hundred eighty-eight individual clones from the enriched library were screened for binding to
B. pertussis
cells, filamentous hemagglutinin (FHA), and pertactin (PRN) in enzyme-linked immunosorbent assays (ELISAs). Based on the binding ability, the clones were put into eight groups. The scFv DNA inserts from the 288 clones were digested with BstOI, and 18 unique restriction patterns, named types 1 to 18, were found. Eight clones (types 1 to 7 and 18) were selected for further testing against FHA, PRN, and
B. pertussis
by ELISA. The results showed that types 1, 5, 7, and 18 bound strongly to
B. pertussis
cells as well as FHA and PRN. Type 3 bound strongly to the cells and FHA but weakly to PRN. Types 4 and 6 bound FHA only, and type 2 did not bind to the cells or antigens. The ability of the eight clones to inhibit
B. pertussis
from binding to HEp-2 cells was assayed. Types 1, 5, and 7, but not the remaining clones, inhibited the adherence of
B. pertussis
to HEp-2 cells. The scFvs were sequenced, and the deduced amino acid sequence showed that the scFvs were different antibodies. Maltose-binding protein (MBP) fusion proteins composed of three different regions of FHA (heparin-binding domain, carbohydrate recognition domain, and the RGD triplet motif) were constructed. The three fusion proteins and Mal85 (MBP-FHA type I domain) were used to map the binding sites for scFvs of types 1, 5, and 7 by ELISA. The results showed that all three scFvs bound to the heparin-binding domain fusion protein but not the other fusion proteins. BALB/c mice who received recombinant phage-treated
B. pertussis
had reduced bacterial counts in the nasal cavity, trachea, and lungs compared to the control groups.
Systemic Translocation of
Salmonella enterica
Serovar Dublin in Cattle Occurs Predominantly via Efferent Lymphatics in a Cell-Free Niche and Requires Type III Secretion System 1 (T3SS-1) but Not T3SS-2
Authors: Pullinger Gillian D. , Paulin Susan M. , Charleston Bryan , Watson Patricia R. , Bowen Alison J. , Dziva Francis , Morgan Eirwen , Villarreal-Ramos Bernardo , Wallis Timothy S. , Stevens Mark P. 
Published: August 2007

ABSTRACT

Salmonella enterica
is an important diarrheal pathogen, and infections may involve severe systemic sequelae depending on serovar- and host-specific factors. The molecular mechanisms underlying translocation of host-restricted and -specific serovars of
S. enterica
from the intestines to distal organs are ill defined. By surgical cannulation of lymph and blood vessels draining the distal ileum in cattle,
S. enterica
serovar Dublin was observed to translocate predominantly via mesenteric lymph nodes to efferent lymphatics in a manner that correlates with systemic virulence, since the fowl typhoid-associated serovar Gallinarum translocated at a significantly lower level. While both
S. enterica
serovars Dublin and Gallinarum were intracellular while in the intestinal mucosa and associated with major histocompatibility complex class II-positive cells, the bacteria were predominantly extracellular within efferent lymph. Screening of a library of signature-tagged serovar Dublin mutants following oral inoculation of calves defined the role of 36 virulence-associated loci in enteric and systemic phases of infection. The number and proportion of tagged clones reaching the liver and spleen early after oral infection were identical to the values in efferent lymph, implying that this may be a relevant mode of dissemination. Coinfection studies confirmed that lymphatic translocation requires the function of type III secretion system 1 (T3SS-1) but, remarkably, not T3SS-2. This is the first description of the mode and genetics of systemic translocation of serovar Dublin in its natural host.
In Vivo Evidence of
Pseudomonas aeruginosa
Nutrient Acquisition and Pathogenesis in the Lungs of Cystic Fibrosis Patients
Authors: Son Mike S. , Matthews Wallace J. , Kang Yun , Nguyen David T. , Hoang Tung T. 
Published: August 2007

ABSTRACT

One of the hallmarks of
Pseudomonas aeruginosa
infection in cystic fibrosis (CF) patients is very-high-cell-density (HCD) replication in the lung, allowing this bacterium to induce virulence controlled by the quorum-sensing systems. However, the nutrient sources sustaining HCD replication in this chronic infection are largely unknown. Here, we performed microarray studies of
P. aeruginosa
directly isolated from the lungs of CF patients to demonstrate its metabolic capability and virulence in vivo. In vivo microarray data, confirmed by real-time reverse transcription-PCR, indicated that the
P. aeruginosa
population expressed several genes for virulence, drug resistance, and utilization of multiple nutrient sources (lung surfactant lipids and amino acids) contributing to HCD replication. The most abundant lung surfactant lipid molecule, phosphatidylcholine (PC), induces key genes of
P. aeruginosa
pertinent to PC degradation in vitro as well as in vivo within the lungs of CF patients. The results support recent research indicating that
P. aeruginosa
exists in the lungs of CF patients as a diverse population with full virulence potential. The data also indicate that there is deregulation of several pathways, suggesting that there is in vivo evolution by deregulation of a large portion of the transcriptome during chronic infection in CF patients. To our knowledge, this is the first in vivo transcriptome analysis of
P. aeruginosa
in a natural infection in CF patients, and the results indicate several important aspects of
P. aeruginosa
pathogenesis, drug resistance, nutrient utilization, and general metabolism within the lungs of CF patients.
Neutralisation of muscle tumour necrosis factor alpha does not attenuate exercise-induced muscle pain but does improve muscle strength in healthy male volunteers
Authors: Rice T L , Chantler I , Loram L C 
Published: August 2007

Objective:Inflammatory mediators, such as tumour necrosis factor alpha (TNFα), may contribute to delayed-onset muscle soreness. The effect of neutralising TNFα with etanercept, a soluble TNFα receptor, on delayed-onset muscle soreness (DOMS) induced in the quadriceps muscle was analysed.Design:On two separate occasions at least 6 weeks apart, etanercept 25 mg or vehicle was given subcutaneously 1 hour before unaccustomed exercise to 12 healthy men in a randomised double-blind cross-over format. To induce DOMS, subjects completed 4 sets of 15 repetitions at 80% of their one-repetition maximum (1RM), using a 45° inclined leg press. Muscle soreness was assessed using a 100-mm visual analogue scale (VAS), and pressure pain threshold (PPT) on the thigh before and 24, 48 and 72 hours after exercise. Changes in the subject’s muscle strength were detected by reassessing the subject’s 1RM 24, 48 and 72 hours after exercise.Results:Muscle strength decreased 24 and 48 hours after exercise regardless of agent administered (analysis of variance, p<0.001). At 72 hours after exercise, muscle strength was significantly greater (p<0.01) after etanercept than after placebo. The exercise protocol induced significant DOMS for up to 72 hours, as reflected by reduced PPT and increased VAS scores (p<0.001). Etanercept had no effect on PPT or VAS.Conclusion:TNFα does not affect muscle soreness associated with unaccustomed exercise, but may improve the recovery of muscle function.