bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vasoconstrictor Administration During Cardiopulmonary Bypass Affects Acid–Base Balance in Infants and Children
Authors: Sato Koichi , Watanabe Hiroshi , Sogawa Masakazu , Takahashi Masashi , Namura Osamu , Takekubo Masaru , Hayashi Jun‐ichi 
Published: January 2006

Abstract:  Background: In experimental reports, blood flow redistribution occurred during cardiopulmonary bypass (CPB) and perfusion pressure was restored by vasoconstrictor administration without improving splanchnic perfusion. The influence of vasoconstrictor administration during CPB was clinically examined.Materials and Methods: Twenty‐two consecutive pediatric CPB cases of ventricular septal defect without blood transfusion were divided into two groups, depending upon whether a vasoconstrictor was administered during CPB or not (n = 7 vs. 15). Bypass flow and systemic perfusion pressure during CPB were maintained at 2.5 L/m2/min and not lower than 30 mm Hg by vasoconstrictor administration, respectively.Results: Although preoperative state and CPB conditions were comparable between the two groups, more sodium bicarbonate was administered (P < 0.05); duration from the operation to extubation was longer (P < 0.05); and bowel movement occurred later in the vasoconstrictor‐administered group than in the control group. Conclusions: Vasoconstrictor administration during CPB may deteriorate the acid–base balance and the postoperative state in infants and children.
Information Uncertainty and Stock Returns
Authors: ZHANG X. FRANK 
Published: January 2006

ABSTRACTThere is substantial evidence of short‐term stock price continuation, which the prior literature often attributes to investor behavioral biases such as underreaction to new information. This paper investigates the role of information uncertainty in price continuation anomalies and cross‐sectional variations in stock returns. If short‐term price continuation is due to investor behavioral biases, we should observe greater price drift when there is greater information uncertainty. As a result, greater information uncertainty should produce relatively higher expected returns following good news and relatively lower expected returns following bad news. My evidence supports this hypothesis.
Asset Pricing Implications of Nonconvex Adjustment Costs and Irreversibility of Investment
Authors: COOPER ILAN 
Published: January 2006

ABSTRACTThis paper derives a real options model that accounts for the value premium. If real investment is largely irreversible, the book value of assets of a distressed firm is high relative to its market value because it has idle physical capital. The firm's excess installed capital capacity enables it to fully benefit from positive aggregate shocks without undertaking costly investment. Thus, returns to equity holders of a high book‐to‐market firm are sensitive to aggregate conditions and its systematic risk is high. Simulations indicate that the model goes a long way toward accounting for the observed value premium.
The Price Impact and Survival of Irrational Traders
Authors: KOGAN LEONID , ROSS STEPHEN A. , WANG JIANG , WESTERFIELD MARK M. 
Published: January 2006

ABSTRACTMilton Friedman argued that irrational traders will consistently lose money, will not survive, and, therefore, cannot influence long‐run asset prices. Since his work, survival and price impact have been assumed to be the same. In this paper, we demonstrate that survival and price impact are two independent concepts. The price impact of irrational traders does not rely on their long‐run survival, and they can have a significant impact on asset prices even when their wealth becomes negligible. We also show that irrational traders' portfolio policies can deviate from their limits long after the price process approaches its long‐run limit.
Wealth and Executive Compensation
Authors: BECKER BO 
Published: January 2006

ABSTRACTUsing new data on the wealth of Swedish CEOs, I show that higher wealth CEOs receive stronger incentives. Since high wealth (excluding own‐firm holdings) implies low absolute risk aversion, this is consistent with a risk aversion explanation. To examine whether wealth is likely to proxy for power, I use lagged wealth (typically measured before the CEO was hired), and the results remain for one of two incentive measures. Also, the wealth–incentive result is not stronger for CEOs likely to face limited owner oversight. Finally, wealth is unrelated to pay levels, and is hence unlikely to proxy for skill.
Initial Public Offerings: An Analysis of Theory and Practice
Authors: BRAU JAMES C. , FAWCETT STANLEY E. 
Published: January 2006

ABSTRACTWe survey 336 chief financial officers (CFOs) to compare practice to theory in the areas of initial public offering (IPO) motivation, timing, underwriter selection, underpricing, signaling, and the decision to remain private. We find the primary motivation for going public is to facilitate acquisitions. CFOs base IPO timing on overall market conditions, are well informed regarding expected underpricing, and feel underpricing compensates investors for taking risk. The most important positive signal is past historical earnings, followed by underwriter certification. CFOs have divergent opinions about the IPO process depending on firm‐specific characteristics. Finally, we find the main reason for remaining private is to preserve decision‐making control and ownership.
Finance as a Barrier to Entry: Bank Competition and Industry Structure in Local U.S. Markets
Authors: CETORELLI NICOLA , STRAHAN PHILIP E. 
Published: January 2006

ABSTRACTThis paper tests how competition in local U.S. banking markets affects the market structure of nonfinancial sectors. Theory offers competing hypotheses about how competition ought to influence firm entry and access to bank credit by mature firms. The empirical evidence, however, strongly supports the idea that in markets with concentrated banking, potential entrants face greater difficulty gaining access to credit than in markets in which banking is more competitive.
Investor Tax Heterogeneity and Ex‐Dividend Day Trading Volume
Authors: DHALIWAL DAN , LI OLIVER ZHEN 
Published: January 2006

ABSTRACTWe propose that ex‐dividend day excess volume is motivated by tax heterogeneity among investors, and thus is increasing in investor tax heterogeneity. Institutional ownership is our measure of heterogeneity. Since investor heterogeneity is a concave function of institutional ownership, we hypothesize that ex‐day volume is a concave function of institutional ownership. Cross‐sectional tests support the tax‐motivated trading hypothesis. Additional tests, using trade size and pension ownership as proxies for institutional trades, yield similar results. We contribute to the literature by considering the interaction between payout policy and ownership structure in explaining the cross‐sectional variation in ex‐day volume.
Histopathological changes in oral mucosa due to takhzeen al‐qat: a study of 70 biopsies
Authors: Ali Aiman A. , Al‐Sharabi Ali K. , Aguirre José M. 
Published: January 2006

Background:  Chewing qat leaves (takhzeen al‐qat) is a common habit in East Africa and Yemen. It has been reported to cause different systemic effects. At the oral mucosa, it causes clinical changes that appear as white lesions. The aim of this paper was to study the histopathological changes in the oral mucosa related to takhzeen al‐qat.Method:  Seventy biopsies were studied. Biopsies were divided into three groups: (G1) Forty biopsies were taken from the oral mucosa of the chewing side. (G2) Twenty biopsies were taken from the oral mucosa of the opposite side and (G3) 10 biopsies were taken from the oral mucosa of non‐chewing volunteers. All biopsies were conventionally prepared, paraffin embedded and histopathological protocol was followed for each case to study the histopathological changes.Results:  Acanthosis appeared in 97.5% (G1) and 50% (G2), parakeratosis in 45% (G1) and 0% (G2), orthokeratosis in 25% (G1) and 10% (G2), abnormal rete ridges in 97.5% (G1) and 25% (G2), intracellular edema in 80% (G1) and 65% (G2), inflammatory infiltration in the subjacent connective tissue of 55% (G1) and 5% (G2), increased amount of collagenous fibers in 47.5% (G1) and 0% (G2), and mild epithelial dysplasia in 25% (G1) and 0% (G2). Biopsies taken from G3 showed no histopathological changes except one case with intracellular edema. Differences were statistically significant.Conclusion:  Takhzeen al‐qat caused histopathological changes in the oral mucosa at the side of chewing; however, these changes were innocuous and without any evidence of malignancy.
Oral tuberculosis associated with a treatment with anti‐rheumatic drugs
Authors: Kolokotronis Alexandros , Avramidou Evanda , Zaraboukas Thomas , Mandraveli Kalliopi , Alexiou Stella , Antoniades Demetrios 
Published: January 2006

Background:  The use of immunosuppressive medication is a dominant risk factor for infection in patients with rheumatoid arthritis (RA). Methotrexate (MTX) is one of the traditional disease‐modifying antirheumatic drugs. Adalimumab [a human anti‐tumor necrosis factor‐α (anti‐TNF‐α) monoclonal antibody] represent an important advance in the treatment of RA and has been recently come in use. TNF‐α plays a role in the host defense against Mycobacterium tuberculosis and notably in granuloma formation. Infections occur at a high rate among those who use one or the combination of the two medications.Method:  We examined a female patient that was referred to our department for evaluation and treatment of a granular lesion on the soft palate and uvula, complaining of mild dysphagia. The patient was treated for 4 months with MTX and adalimumab for RA before the oral lesion appeared.Results:  The histopathological examination of a specimen of the oral lesion, taken by biopsy, showed a chronic inflammation characterized by tuberculous granulomas. Polymerase chain reaction test and culture of a new specimen was positive for M. tuberculosis.Conclusions:  The therapeutic use of MTX or/and adalimumab for the treatment of RA or few others diseases, can cause oral tuberculosis.
Relationship between TNF‐α and TUNEL‐positive chondrocytes in antigen‐induced arthritis of the rabbit temporomandibular joint
Authors: Hirota Yuriko , Habu Manabu , Tominaga Kazuhiro , Sukedai Miho , Matsukawa Akihiro , Nishihara Tatsuji , Fukuda Jinichi 
Published: January 2006

Background:  Terminal deoxynucleotidyl transferase‐mediated deoxyuridine triphosphate biotin nick end‐labeling (TUNEL) staining is a widely accepted method for the detection of DNA fragmentation in nuclei of apoptotic cells. Tumor necrosis factor (TNF)‐α is closely associated with changes in condylar cartilage and modulates apoptosis in various tissues including cartilage. The aim of this study was to investigate the relationship between apoptotic chondrocytes and TNF‐α in a rabbit model of arthritis.Method:  Unilateral temporomandibular joint (TMJ) arthritis was induced in 20 adult New Zealand White rabbits. From 1 day to 6 weeks after the induction of arthritis, immunohistochemical analysis for TNF‐α and TUNEL was performed.Results:  In condylar cartilage, TNF‐α‐positive cells and TUNEL‐positive cells were localized together. TNF‐α‐positive chondrocytes seemed to precede TUNEL‐positive cells.Conclusions:  The results of the present study suggest that TNF‐α may be involved in apoptosis and/or apoptotic necrosis of chondrocytes as TMJ arthritis progresses from the acute to chronic stage.
Isolation and characterization of synovial cells from the human temporomandibular joint
Authors: Nagai H. , Miyamoto Y. , Nakata A. , Hatakeyama S. , Iwanami Y. , Fukuda M. 
Published: January 2006

Background:  The synovial tissues with temporomandibular disorders (TMDs) often show chronic inflammatory changes and the synovial cells participate in the pathogenic processes of TMDs. The synovial membrane is composed of a synovial lining layer and a connective sublining layer. The synovial lining layer is made up of two kinds of cells: macrophage‐like type A and fibroblastic type B cells. The aim of this study was to isolate and characterize synovial cells from the human temporomandibular joint (TMJ).Methods:  Synovial cells were isolated using an explant culture method. Then, we characterized the cultured synovial cells (SGA2 cells) using immunocytochemistry.Results:  SGA2 cells expressed the fibroblastic markers vimentin and prolyl 4‐hydroxylase; they also expressed laminin and heat shock protein 27, all of which are markers of type B cells. However, some cells expressed the macrophage marker CD68. These CD68‐positive cells simultaneously expressed laminin.Conclusions:  We isolated and cultured synovial type B cells from the human TMJ, and identified the presence of intermediate type synovial lining cells, having the phenotypic properties of both type A and type B cells, among the synovial lining cells.
The efficacy of amelxanox OraDiscTM on the prevention of recurrent minor aphthous ulceration
Authors: Murray B. , Biagioni P. A. , Lamey P.‐J. 
Published: January 2006

Background:  The study was designed to determine the efficacy of OraDiscTM (active component 2 mg amlexanox) on the prevention of aphthous ulcers treated at the prodromal stage.Methods:  Thermographic imaging was used to confirm the presence of a prodromal ulcer. Fifty‐two patients were randomized to receive OraDiscTM (N = 26) or vehicle patches (N = 26). Patches were applied four times a day for 72 h over the prodromal area. The percentage of subjects who developed an ulcer at 72 h was compared between groups using the Fisher's exact test.Results:  About 50% of subjects in the OraDiscTM group developed an ulcer by day 4 compared with 69% in the vehicle group. Erythema score, ulcer size, pain scores and thermographically active area and temperature all showed trends towards healing in the OraDiscTM group.Conclusion:  The OraDiscTM prevents ulcers from developing when compared with the vehicle patch.
Effects of Patch Size and Floral Herbivory on Seed Set in Trichogoniopsis adenantha (Asteraceae) in Southeastern Brazil1
Authors: Salomão Adriana T. , Martins Luiz F. , Ribeiro Ricardo da S. , Romero Gustavo Q. 
Published: January 2006

ABSTRACTThe effects of patch size and floral herbivory on reproductive success of Trichogoniopsis adenantha (Asteraceae) were studied in a semideciduous forest in southeastern Brazil. Plants in large patches and capitula not attacked by endophagous insects had higher seed set. The consequences of living in large or small patches for plant reproductive success are discussed.
Lifetime of Imidazolium Salts at Elevated
Temperatures
Authors: Blake Daniel M. , Moens Luc , Rudnicki Daniel , Pilath Heidi 
Published: January 2006

Abstract
This report summarizes progress to date on the thermal stability of imidazolium salts being considered for application as heat transfer and thermal storage fluids in solar parabolic trough power systems. Imidazolium salts are a subset of the general class of molten salts. They are termed ionic liquids because many have freezing points at or below room temperature. This class of salts was selected for initial study because there were many examples that were reported to be stable at high temperatures. These reports were usually based on the results of standard thermal gravimetric analysis (TGA) methods. Work by our subcontractor at the University of Alabama and at NREL showed that slow heating rates or when the temperature is held constant for long times resulted in decomposition temperatures that are much lower than those found with the usual TGA methods. We have used a TGA technique that allows calculation of the rates of thermal decomposition as a function of temperature. The results lead us to the conclusion that the imidazolium salts known to be the most thermally stable would not have useful lifetimes above about 200°C. At present this determination is based on the rough approximation that the fluid in a solar trough system experiences a constant, high temperature. Better estimates of the useful lifetime will require a system model that takes into account the time at temperature distribution of a fluid moving through the different components in a solar plant.
Characterization of the Biosynthetic Pathway of Glucosylglycerate in the Archaeon
Methanococcoides burtonii
Authors: Costa Joana , Empadinhas Nuno , Gonçalves Luís , Lamosa Pedro , Santos Helena , da Costa Milton S. 
Published: January 2006

ABSTRACT

The pathway for the synthesis of the organic solute glucosylglycerate (GG) is proposed based on the activities of the recombinant glucosyl-3-phosphoglycerate synthase (GpgS) and glucosyl-3-phosphoglycerate phosphatase (GpgP) from
Methanococcoides burtonii
. A mannosyl-3-phosphoglycerate phosphatase gene homologue (
mpgP
) was found in the genome of
M. burtonii
(
http://www.jgi.doe.gov
), but an
mpgS
gene coding for mannosyl-3-phosphoglycerate synthase (MpgS) was absent. The gene upstream of the
mpgP
homologue encoded a putative glucosyltransferase that was expressed in
Escherichia coli
. The recombinant product had GpgS activity, catalyzing the synthesis of glucosyl-3-phosphoglycerate (GPG) from GDP-glucose and
d
-3-phosphoglycerate, with a high substrate specificity. The recombinant MpgP protein dephosphorylated GPG to GG and was also able to dephosphorylate mannosyl-3-phosphoglycerate (MPG) but no other substrate tested. Similar flexibilities in substrate specificity were confirmed in vitro for the MpgPs from
Thermus thermophilus
,
Pyrococcus horikoshii
, and “
Dehalococcoides ethenogenes
.” GpgS had maximal activity at 50°C. The maximal activity of GpgP was at 50°C with GPG as the substrate and at 60°C with MPG. Despite the similarity of the sugar donors GDP-glucose and GDP-mannose, the enzymes for the synthesis of GPG or MPG share no amino acid sequence identity, save for short motifs. However, the hydrolysis of GPG and MPG is carried out by phosphatases encoded by homologous genes and capable of using both substrates. To our knowledge, this is the first report of the elucidation of a biosynthetic pathway for glucosylglycerate.
Complex Regulation of Arsenite Oxidation in
Agrobacterium tumefaciens
Authors: Kashyap Des R. , Botero Lina M. , Franck William L. , Hassett Daniel J. , McDermott Timothy R. 
Published: January 2006

ABSTRACT

Seminal regulatory controls of microbial arsenite [As(III)] oxidation are described in this study. Transposon mutagenesis of
Agrobacterium tumefaciens
identified genes essential for As(III) oxidation, including those coding for a two-component signal transduction pair. The transposon interrupted a response regulator gene (referred to as
aoxR
), which encodes an
ntrC
-like protein and is immediately downstream of a gene (
aoxS
) encoding a protein with primary structural features found in sensor histidine kinases. The structural genes for As(III) oxidase (
aoxAB
), a
c
-type cytochrome (
cytc
2
), and molybdopterin biosynthesis (
chlE
) were downstream of
aoxR
. The mutant could not be complemented by
aoxSR
in
trans
but was complemented by a clone containing
aoxS
-
aoxR
-
aoxA
-
aoxB
-
cytc
2
and consistent with reverse transcriptase (RT) PCR experiments, which demonstrated these genes are cotranscribed as an operon. Expression of
aoxAB
was monitored by RT-PCR and found to be up-regulated by the addition of As(III) to cell cultures. Expression of
aoxAB
was also controlled in a fashion consistent with quorum sensing in that (i) expression of
aoxAB
was absent in As(III)-unexposed early-log-phase cells but was observed in As(III)-unexposed, late-log-phase cells and (ii) treating As(III)-unexposed, early-log-phase cells with ethyl acetate extracts of As(III)-unexposed, late-log-phase culture supernatants also resulted in
aoxAB
induction. Under inducing conditions,
aoxS
expression was readily observed in the wild-type strain but significantly reduced in the mutant, indicating that AoxR is autoregulatory and at least partially controls the expression of the
aox
operon. In summary, regulation of
A. tumefaciens
As(III) oxidation is complex, apparently being controlled by As(III) exposure, a two-component signal transduction system, and quorum sensing.
The Fnr Regulon of
Bacillus subtilis
Authors: Reents Heike , Münch Richard , Dammeyer Thorben , Jahn Dieter , Härtig Elisabeth 
Published: January 2006

ABSTRACT

The
Bacillus subtilis
transcriptional regulator Fnr is an integral part of the regulatory cascade required for the adaptation of the bacterium to low oxygen tension. The
B. subtilis
Fnr regulon was defined via transcriptomic analysis in combination with bioinformatic-based binding site prediction. Four distinct groups of Fnr-dependent genes were observed. Group 1 genes (
narKfnr
,
narGHJI
, and
arfM
) are generally induced by Fnr under anaerobic conditions. All corresponding promoters contain an essential Fnr-binding site centered −41.5/−40.5 bp upstream of the transcriptional start point, suggesting their induction by direct Fnr interaction. Group 2 genes (
alsSD
,
ldh lctP
,
ywcJ
, and
cydABCD
) are characterized by anaerobic repression in the presence of nitrate. Mutational analysis of the Fnr-binding sites found in three of the corresponding promoters excluded their function in Fnr-mediated repression. Genetic evidence showing that group 2 genes are anaerobically repressed by nitrate reductase formation was accumulated. A possible role of the redox regulator YdiH in the regulation of group 2 genes was initially investigated. Group 3 genes are characterized by their Fnr-dependent activation in the presence of nitrate and the lack of an Fnr-binding site in their promoters. The analysis of Group 3 gene transcription (
ykuNOP
and
ydbN
) indicated that Fnr induces nitrate reductase production, which leads to the formation of the regulatory compound nitrite from nitrate. Finally, the group 4 operon
acoABCL
, lacking an Fnr-binding site, requires Fnr-dependent nitrate reductase formation for its general anaerobic induction. A regulatory model for the observed complex Fnr-mediated gene expression was deduced.
Serotype Differences and Lack of Biofilm Formation Characterize
Yersinia pseudotuberculosis
Infection of the
Xenopsylla cheopis
Flea Vector of
Yersinia pestis
Authors: Erickson David L. , Jarrett Clayton O. , Wren Brendan W. , Hinnebusch B. Joseph 
Published: January 2006

ABSTRACT

Yersinia pestis
, the agent of plague, is usually transmitted by fleas. To produce a transmissible infection,
Y. pestis
colonizes the flea midgut and forms a biofilm in the proventricular valve, which blocks normal blood feeding. The enteropathogen
Yersinia pseudotuberculosis
, from which
Y. pestis
recently evolved, is not transmitted by fleas. However, both
Y. pestis
and
Y. pseudotuberculosis
form biofilms that adhere to the external mouthparts and block feeding of
Caenorhabditis elegans
nematodes, which has been proposed as a model of
Y. pestis
-flea interactions. We compared the ability of
Y. pestis
and
Y. pseudotuberculosis
to infect the rat flea
Xenopsylla cheopis
and to produce biofilms in the flea and in vitro. Five of 18
Y. pseudotuberculosis
strains, encompassing seven serotypes, including all three serotype O3 strains tested, were unable to stably colonize the flea midgut. The other strains persisted in the flea midgut for 4 weeks but did not increase in numbers, and none of the 18 strains colonized the proventriculus or produced a biofilm in the flea.
Y. pseudotuberculosis
strains also varied greatly in their ability to produce biofilms in vitro, but there was no correlation between biofilm phenotype in vitro or on the surface of
C. elegans
and the ability to colonize or block fleas. Our results support a model in which a genetic change in the
Y. pseudotuberculosis
progenitor of
Y. pestis
extended its pre-existing ex vivo biofilm-forming ability to the flea gut environment, thus enabling proventricular blockage and efficient flea-borne transmission.