bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multivariate Exponential Tilting and Pricing Implications for Mortality Securitization
Authors: Cox Samuel H. , Lin Yijia , Wang Shaun 
Published: December 2006

AbstractNormalized exponential tilting is an extension of classical theories, including the Capital Asset Pricing Model (CAPM) and the Black–Merton–Scholes model, to price risks with general‐shaped distributions. The need for changing multivariate probability measures arises in pricing contingent claims on multiple underlying assets or liabilities. In this article, we apply it to valuation of mortality‐based securities written on mortality indices of several countries. We show how to use multivariate exponential tilting to price the first pure mortality security, the Swiss Re bond. The same technique can be applied in other mortality securitization pricing.
Roles of reactive oxygen species in the corpus luteum
Authors: SUGINO Norihiro 
Published: December 2006

ABSTRACTCells living under aerobic conditions always face the oxygen paradox. Oxygen is necessary for cells to maintain their lives. However, reactive oxygen species such as superoxide radicals, hydroxyl radicals and hydrogen peroxide are generated from oxygen and damage cells. Oxidative stress occurs as a consequence of the excessive production of reactive oxygen species and impaired antioxidant defense systems. Antioxidant enzymes include superoxide dismutase (SOD), which is a specific enzyme to scavenge superoxide radicals; copper‐zinc SOD, located in the cytosol and Mn‐SOD, located in the mitochondria. Both types of SOD belong to the first enzymatic step to scavenge superoxide radicals. It has been reported that a number of local factors such as cytokines, growth factors and eicosanoids are involved in the regulation of the corpus luteum (CL) function in addition to gonadotropins. Since reactive oxygen species are generated and SOD is expressed in the CL, there is a possibility that reactive oxygen species and SOD work as local regulators of the CL function. The present review reports that reactive oxygen species and their scavenging systems play important roles in the regulation of the CL function.
Molecular cloning and expression analysis of cDNA encoding bovine adipogenin
Authors: HONG Yeon‐Hee , OGIHARA Yumi , HISHIKAWA Daisuke , GOTOH Chizu , IGA Tomoyo , SUZUKI Yasuki , SONG Sang‐Houn , NAKAJIMA Keiichi , KOZAKAI Takaharu , SASAKI Shin‐ichi , ROH Sang‐Gun 
Published: December 2006

ABSTRACTAdipose tissue plays a central role in energy homeostasis. In a previous report, we reported adipogenin, an adipocyte‐specific membrane protein whose expression is higher in fat and increases during the adipocyte differentiation of 3T3‐L1 cells, as a candidate gene for involvement in adipogenesis. Here, we isolated the bovine adipogenin gene using in silico cloning and the target region for polymerase chain reaction amplification in the database. cDNA, including a 246 base pair (bp) open reading frame, was identified in the adipose tissues of cattle. In silico gene analysis showed that the bovine adipogenin‐encoded protein has a predicted MW of 9882.45, encoding 81 amino acids and located on bovine chromosome 13. The deduced amino acid sequence of bovine adipogenin conserved 86%, 66% and 78% identity with that in pigs, mice and humans, respectively. A semi‐quantitative reverse transcriptase polymerase chain reaction showed that bovine adipogenin mRNA was more highly expressed in subcutaneous, perirenal and mescentric adipose tissue than in non‐adipose tissue. The level of bovine adipogenin mRNA is dramatically elevated during the adipocyte differentiation of four different kinds of preadipocytes prepared from subcutaneous, perirenal, mesenteric and parametrial adipose tissues. Our results suggest that adipogenin plays an important role in the regulation of adipocyte development in cattle and may be a strong candidate gene for obesity in mammals.
A Cytotoxic Neolignan from Schisandra propinqua (Wall.) Baill.
Authors: Xu Li‐Jia , Huang Feng , Chen Si‐Bao , Li Lian‐Niang , Chen Shi‐Lin , Xiao Pei‐Gen 
Published: December 2006

AbstractIn the course of our study of bioactive natural products from Schisandra plants, we isolated a neolignan from an EtOAc extract of the stems of Schisandra propinqua (Wall.) Baill. The structure of the new compound was determined to be 4, 4‐di (4‐hydroxy‐3‐methoxyphenly)‐2, 3‐dimethylbutanol (compound 1) on the basis of 1H‐ and 13C‐NMR spectra and 2D NMR methods. Eight known compounds, compounds 2‐9, were also isolated and identified, of which compounds 3, 4, 6 and 9 were isolated for the first time from this plant. In addition, compounds 1‐4 were evaluated for cytotoxicity by an 3‐(4,5‐dimethyl‐2 thiazoyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT) assay. Compound 1 showed significant potential cytotoxic ability in the bioassay.(Managing editor: Wei Wang)
In Vitro and In Vivo Activities of a New Cephalosporin, FR264205, against
Pseudomonas aeruginosa
Authors: Takeda Shinobu , Nakai Toru , Wakai Yoshimi , Ikeda Fumiaki , Hatano Kazuo 
Published: December 2006

ABSTRACT

FR264205 is a novel parenteral 3′-aminopyrazolium cephalosporin. This study evaluated the in vitro and in vivo activities of FR264205 against
Pseudomonas aeruginosa
. The MIC of FR264205 at which 90% of 193 clinical isolates of
P. aeruginosa
were inhibited was 1 μg/ml, 8- to 16-fold lower than those of ceftazidime (CAZ), imipenem (IPM), and ciprofloxacin (CIP). FR264205 also exhibited this level of activity against CAZ-, IPM-, and CIP-resistant
P. aeruginosa
. The reduction in the susceptibility of FR264205 by AmpC β-lactamase was lower than that of CAZ, indicating a relatively high stability of FR264205 against AmpC β-lactamase, the main resistance mechanism for cephalosporins. Neither expression of efflux pumps nor deficiency of OprD decreased the activity of FR264205. No spontaneous resistance mutants were selected in the presence of FR264205, and the reduction in susceptibility to FR264205 was lower than that to CAZ, IPM, and CIP after serial passage, suggesting that FR264205 has a low propensity for selecting resistance. In murine pulmonary, urinary tract, and burn wound models of infection caused by
P. aeruginosa
, the efficacy of FR264205 was superior or comparable to those of CAZ and IPM. These results indicate that FR264205 should have good potential as an antibacterial agent for
P. aeruginosa
.
Synergistic Interaction between Phenothiazines and Antimicrobial Agents against
Burkholderia pseudomallei
Authors: Chan Ying Ying , Ong Yong Mei , Chua Kim Lee 
Published: December 2006

ABSTRACT

The gram-negative soil bacillus
Burkholderia pseudomallei
is the causative agent of melioidosis, a severe and potentially fatal septicemic disease that is endemic to Southeast Asia and northern Australia. Its intrinsic resistance to many antibiotics is attributed mainly to the presence of several drug efflux pumps, and therefore, inhibitors of such pumps are expected to restore the activities of many clinically important antimicrobial agents that are the substrates of these pumps. The phenothiazine antipsychotic and antihistaminic drugs prochlorperazine, chlorpromazine, and promazine have a synergistic interaction with a wide spectrum of antimicrobial agents, thereby enhancing their antimicrobial potency against
B. pseudomallei
. Antimicrobial agents that interacted synergistically with the phenothiazines include streptomycin, erythromycin, oleandomycin, spectinomycin, levofloxacin, azithromycin, and amoxicillin-clavulanic acid. The MICs of these antibiotics were reduced as much as 8,000-fold in the presence of the phenothiazines. Antimicrobial agents which did not interact synergistically with the phenothiazines include gentamicin, amoxicillin, and ampicillin. Omeprazole, a proton pump inhibitor, provided an augmentation of antimicrobial activities similar to that of the phenothiazines, suggesting that the phenothiazines might have interfered with the proton gradient at the inner membrane.
B. pseudomallei
cells accumulated more erythromycin in the presence of the phenothiazines, an effect similar to that of carbonyl cyanide
m
-chlorophenylhydrazone, a proton gradient uncoupler. In the presence of the phenothiazines, a much reduced concentration of erythromycin (0.06× MIC) also protected human lung epithelial cells and macrophage cells from
B. pseudomallei
infection and attenuated its cytotoxicity.
Cysteine Protease Inhibitors Block
Toxoplasma gondii
Microneme Secretion and Cell Invasion
Authors: Teo Chin Fen , Zhou Xing Wang , Bogyo Matthew , Carruthers Vern B. 
Published: December 2006

ABSTRACT

Toxoplasma gondii
enters host cells via an active, self-driven process to fulfill its need for intracellular replication and survival. Successful host cell invasion is governed by sequential release of secretory proteins from three specialized organelles, including the micronemes, which contribute adhesive proteins necessary for parasite attachment and penetration. Cumulative evidence from studies of
Trypanosoma
species and malaria parasites has shown that cysteine protease inhibitors represent potent anti-parasitic agents capable of curing infections in vivo. In this study, we screened a series of selective cysteine protease inhibitors for their effects on
T. gondii
cell invasion. Two of these compounds, morpholinourea-leucyl-homophenolalaninyl-phenyl-vinyl-sulfone and
N
-benzoxycarbonyl-(leucyl)
3
-phenyl-vinyl-sulfone, impaired
T. gondii
invasion and gliding motility at low-micromolar concentrations. Unexpectedly, these inhibitors did not affect surface proteolysis of microneme products but instead impaired an earlier step by precluding the secretion of microneme-derived adhesins to the parasite surface. Our findings suggest that cysteine protease activity is required for microneme secretion and cell invasion by
T. gondii
.
Cytotoxic Effect of Curcumin on Malaria Parasite
Plasmodium falciparum
: Inhibition of Histone Acetylation and Generation of Reactive Oxygen Species
Authors: Cui Long , Miao Jun , Cui Liwang 
Published: December 2006

ABSTRACT

The emergence of multidrug-resistant parasites is a major concern for malaria control, and development of novel drugs is a high priority. Curcumin, a natural polyphenolic compound, possesses diverse pharmacological properties. Among its antiprotozoan activities, curcumin was potent against both chloroquine-sensitive and -resistant
Plasmodium falciparum
strains. Consistent with findings in mammalian cell lines, curcumin's prooxidant activity promoted the production in
P. falciparum
of reactive oxygen species (ROS), whose cytotoxic effect could be antagonized by coincubation with antioxidants and ROS scavengers. Curcumin treatment also resulted in damage of both mitochondrial and nuclear DNA, probably due to the elevation of intracellular ROS. Furthermore, we have demonstrated that curcumin inhibited the histone acetyltransferase (HAT) activity of the recombinant
P. falciparum
general control nonderepressed 5 (PfGCN5) in vitro and reduced nuclear HAT activity of the parasite in culture. Curcumin-induced hypoacetylation of histone H3 at K9 and K14, but not H4 at K5, K8, K12, and K16, suggested that curcumin caused specific inhibition of the PfGCN5 HAT. Taken together, these results indicated that at least the generation of ROS and down-regulation of PfGCN5 HAT activity accounted for curcumin's cytotoxicity for malaria parasites.
IS
21-558
Insertion Sequences Are Involved in the Mobility of the Multiresistance Gene
cfr
Authors: Kehrenberg Corinna , Aarestrup Frank M. , Schwarz Stefan 
Published: December 2006

ABSTRACT

During a study of florfenicol-resistant porcine staphylococci from Denmark, the genes
cfr
and
fexA
were detected in the chromosomal DNA or on plasmids of
Staphylococcus hyicus
,
Staphylococcus warneri
, and
Staphylococcus simulans
. A novel variant of the phenicol resistance transposon Tn
558
was detected on the ca. 43-kb plasmid pSCFS6 in
S. warneri
and
S. simulans
isolates. Sequence analysis of a 22,010-bp segment revealed that the new Tn
558
variant harbored an additional resistance gene region integrated into the
tnpC
reading frame. This resistance gene region consisted of the clindamycin exporter gene
lsa
(B) and the gene
cfr
for combined resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A antibiotics bracketed by IS
21-558
insertion sequences orientated in the same direction. A 6-bp target site duplication was detected at the integration site within
tnpC
. Transpositionally active forms of the IS
21-558
element, known as minicircles, were detected by PCR and suggest that this insertion sequence is involved in the mobility of the multiresistance gene
cfr
. Based on the knowledge of the transposition pathways of IS
21
-like insertion sequences and the sequence features detected, the resistance gene region of plasmid pSCFS6 is believed to have developed via IS
21-558
-mediated cointegrate formation. The data obtained in this study identified the multiresistance gene
cfr
not only in three novel host species but also in a novel genetic context whose further analysis suggested that insertion sequences of the type IS
21-558
are likely to be involved in the dissemination of
cfr
.
Immunochemical Characterization of Temperature-Regulated Production of Enterocin L50 (EntL50A and EntL50B), Enterocin P, and Enterocin Q byEnterococcus faeciumL50
Authors: Criado Raquel , Gutiérrez Jorge , Martín María , Herranz Carmen , Hernández Pablo E. , Cintas Luis M. 
Published: December 2006

ABSTRACTPolyclonal antibodies with specificity for enterocin L50A (EntL50A), enterocin L50B (EntL50B), and enterocin Q (EntQ) produced byEnterococcus faeciumL50 have been generated by immunization of rabbits with chemically synthesized peptides derived from the C terminus of EntL50A (LR1) and EntL50B (LR2) and from the complete enterocin Q (EntQ) conjugated to the carrier protein keyhole limpet hemocyanin (KLH). The sensitivity and specificity of these antibodies were evaluated by a noncompetitive indirect enzyme-linked immunosorbent assay (NCI-ELISA) and a competitive indirect ELISA (CI-ELISA). The NCI-ELISA was valuable for detecting anti-EntL50A-, anti-EntL50B-, and anti-EntQ-specific antibodies in the sera of the LR1-KLH-, LR2-KLH-, and EntQ-KLH-immunized animals, respectively. Moreover, these antibodies and those specific for enterocin P (EntP) obtained in a previous work (J. Gutiérrez, R. Criado, R. Citti, M. Martín, C. Herranz, M. F. Fernández, L. M. Cintas, and P. E. Hernández, J. Agric. Food Chem.52:2247-2255, 2004) were used in an NCI-ELISA to detect and quantify the production of EntL50A, EntL50B, EntP, and EntQ by the multiple-bacteriocin producerE. faeciumL50 grown at different temperatures (16 to 47°C). Our results show that temperature has a strong influence on bacteriocin production by this strain. EntL50A and EntL50B are synthesized at 16 to 32°C, but production becomes negligible when the growth temperature is above 37°C, whereas EntP and EntQ are synthesized at temperatures ranging from 16 to 47°C. Maximum EntL50A and EntL50B production was detected at 25°C, while EntP and EntQ are maximally produced at 37 and 47°C, respectively. The loss of plasmid pCIZ1 (50 kb) and/or pCIZ2 (7.4 kb), encoding EntL50A and EntL50B as well as EntQ, respectively, resulted in a significant increase in production and stability of the chromosomally encoded EntP.
Quantitative Detection of Hepatitis A Virus and Enteroviruses Near the United States-Mexico Border and Correlation with Levels of Fecal Indicator Bacteria
Authors: Gersberg Richard M. , Rose Michael A. , Robles-Sikisaka Refugio , Dhar Arun K. 
Published: December 2006

ABSTRACT

For decades, untreated sewage flowing northward from Tijuana, Mexico, via the Tijuana River has adversely affected the water quality of the recreational beaches of San Diego, California. We used quantitative reverse transcription-PCR to measure the levels of hepatitis A virus (HAV) and enteroviruses in coastal waters near the United States-Mexico border and compared these levels to those of the conventional fecal indicators,
Escherichia coli
and enterococci. Over a 2-year period from 2003 to 2005, a total of 20 samples were assayed at two sites during both wet and dry weather: the surfzone at the mouth of the Tijuana River and the surfzone near the pier at Imperial Beach (IB), California (about 2 km north of the mouth of the Tijuana River). HAV and enterovirus were detected in 79 and 93% of the wet-weather samples, respectively. HAV concentrations in these samples ranged from 105 to 30,771 viral particles/liter, and enterovirus levels ranged from 7 to 4,417 viral particles/liter. The concentrations of HAV and enterovirus were below the limit of detection for all dry weather samples collected at IB. Regression analyses showed a significant correlation between the densities of both fecal bacterial indicators and the levels of HAV (
R
2
> 0.61,
P
< 0.0001) and enterovirus (
R
2
> 0.70,
P
< 0.0001), a finding that supports the use of conventional bacterial indicators to predict the levels of these viruses in recreational marine waters.
Constitutive Delivery of Bovine β-Lactoglobulin to the Digestive Tracts of Gnotobiotic Mice by EngineeredLactobacillus casei
Authors: Hazebrouck S. , Oozeer R. , Adel-Patient K. , Langella P. , Rabot S. , Wal J.-M. , Corthier G. 
Published: December 2006

ABSTRACTThe gut microbiota is critical for maturation of the immune system. Recent evidence suggests that early establishment of lactobacilli in the intestinal microbiota, during neonatal colonization or by probiotic supplementation, could prevent the development of allergic disorders. Postnatal maturation of the gut immune system with allergen-producing lactobacilli colonizing the digestive tract could then affect the development of further allergic sensitization. In this paper, we describe construction of a recombinantLactobacillus caseistrain that can constitutively deliver bovine β-lactoglobulin (BLG), a major cow's milk allergen, to the guts of gnotobiotic mice. Theblggene was inserted into theL. caseichromosome downstream of an endogenous promoter. BLG production was improved by fusing the propeptide LEISSTCDA (LEISS) to the BLG mature moiety. This led to a 10-fold increase in LEISS-BLG production compared to the production obtained without the propeptide and also led to enhanced secretion corresponding to 5% of the total production. After inoculation into germfree C3H/HeN mice, the genetic stability of the recombinant strain and in vivo BLG production were confirmed for at least 10 weeks. BLG stimulation of spleen cells from mice monoassociated with the BLG-producing lactobacilli induced secretion of the Th1 cytokine gamma interferon and, to a lesser extent, the Th2 cytokine interleukin-5. No BLG-specific immunoglobulin G1 (IgG1), IgG2a, or IgA was detected in sera or in fecal samples. These results suggest that gut colonization with allergen-producing lactobacilli could provide a useful model for studying the modulation of allergic disorders.
Rainfall-Induced Release of Fecal Coliforms and Other Manure Constituents: Comparison and Modeling
Authors: Guber A. K. , Shelton D. R. , Pachepsky Y. A. , Sadeghi A. M. , Sikora L. J. 
Published: December 2006

ABSTRACT

Modeling release of fecal coliforms is an important component of fate and transport simulations related to environmental water quality. Manure constituents other than fecal coliforms may serve as natural tracers of fecal contamination provided that their release from manure to runoff is similar to the fecal coliform release. The objectives of this work were to compare release of fecal coliforms (FC), chloride (Cl
−
), organic carbon (OC), and water-soluble phosphorus (P) from dissolving manure and to assess the performance of three models in describing the observed release. Bovine manure was applied on 0.5- by 0.3-m bare and vegetated subplots with 20% slope on sandy loam and clay loam soils. Concentrations of Cl
−
, FC, OC, and P were measured in runoff collected from troughs at the edges of the subplots at 5-min intervals during 1-h rainfall simulations. The one-parametric exponential model and two-parametric Vadas-Kleinman-Sharpley model and Bradford-Schijven model were fitted to the data. The Bradford-Schijven model had uncorrelated parameters, one of which was linearly related to the irrigation rate, and another parameter reflected the presence or the absence of vegetation. Kinetics of the FC release from manure was similar to the release kinetics of P and OC. The Bradford-Schijven model is recommended to simulate the release of manure constituents.
Engineered Cyanophycin Synthetase (CphA) from
Nostoc ellipsosporum
Confers Enhanced CphA Activity and Cyanophycin Accumulation to
Escherichia coli
Authors: Hai Tran , Frey Kay M. , Steinbüchel Alexander 
Published: December 2006

ABSTRACT

The cyanophycin (CGP) synthetase gene (
cphA
NE1
) of the transposon-induced
argL
mutant NE1 of the cyanobacterium
Nostoc ellipsosporum
, which exhibits a CGP-leaky phenotype during diazotrophical growth, was cloned and expressed in
Escherichia coli
strain TOP10. Its amino acid sequence exhibited high similarities to CphAs of other cyanobacteria. Recombinant cells of
E. coli
, which harbored a fragment comprising the complete
cphA
NE1
gene plus 400 bp of its downstream region in colinear orientation to the
lacZ
promoter, accumulated CGP up to 17 and 8.5% (wt/wt) of cellular dry matter (CDM) if cultivated in complex medium in the presence or absence of isopropyl-β-
d
-thiogalactopyranoside, respectively. Two truncated CphAs, lacking 31 (CphA
NE1del96
) or 59 (CphA
NE1del180
) amino acids of the C-terminal region, were derived from
cphA
NE1
by deleting 96 or 180 bp from its 3′ region through the introduction of stop codons. In comparison to the wild-type gene,
cphA
NE1del96
conferred about 2.1- to 2.2-fold-higher enzyme activity (up to 5.75 U/mg protein) on
E. coli
. Furthermore, these cells accumulated about twofold more CGP (up to 34.5% [wt/wt] of CDM) than cells expressing the wild-type gene. An engineered CphA possessing significantly enhanced activity and conferring the highest CGP content on
E. coli
is demonstrated. In contrast, CphA
NE1del180
was inactive and did not confer CGP accumulation on
E. coli
. Interestingly, a short conserved stretch of 4 to 5 hydrophobic amino acids is located in the protein region present in CphA
NE1del96
but absent in CphA
NE1del180
. In addition, CphA
NE1
and CphA
NE1del96
are, besides CphA from
Acinetobacter baylyi
, the only CphAs exhibiting rigid substrate specificities that do not enable the incorporation of lysine instead of arginine into CGP.