bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietary Gangliosides Enhance in Vitro Lipid Uptake in Weanling Rats
Authors: Birecki Celina J , Drozdowski Laurie A , Suh Miyoung , Park Eek Joong , Clandinin M Tom , Thomson Alan B. R
Published: December 2005

Background:

The intestine adapts morphologically or functionally in response to environmental stimuli. Dietary lipids modify brush border membrane (BBM) permeability and nutrient transporter activities. Gangliosides (GANG) are glycolipids in human milk that are present only in low amounts in infant formula. Exogenous GANG are incorporated into cell membranes and increase their permeability. The objective of this study was to determine whether feeding a GANG‐enriched diet alters in vitro intestinal lipid absorption.

Methods:

Weanling rats were fed either (1) GANG‐enriched diet; (2) diet enriched with polyunsaturated long‐chain fatty acids; or (3) isocaloric control diet for 2 weeks, after which in vitro intestinal lipid uptake was measured.

Results:

Feeding GANG did not alter weight gain or intestinal morphology. Enhanced uptake of stearic acid (18:0) in the ileum and stearic and linoleic acid (18:2) in the jejunum was not associated with a change in the abundance of the ileal lipid binding protein (ILBP), the intestinal fatty acid binding protein (I‐FABP), or the liver fatty acid binding protein (L‐FABP).

Conclusion:

We speculate that the enhanced uptake of long‐chain fatty acids in weanling rats fed GANG may be caused by a modification in physical properties of the BBM.
Nutritional Supplementation with Transforming Growth Factor‐β, Glutamine, and Short Chain Fatty Acids Minimizes Methotrexate‐Induced Injury
Authors: Harsha Wendy T. F , Kalandarova Ellina , McNutt Patrick , Irwin Robert , Noel James
Published: December 2005

Objective:

Gastrointestinal (GI) damage caused by methotrexate (MTX) results in mucosal injury, bacterial invasion, and activation of an immune system that is reduced in function. Diets enriched with glutamine, short chain fatty acids (SCFAs), and transforming growth factor (TGF)‐β have demonstrated decreased infection, weight loss, and GI damage in Crohn disease. We, therefore, sought to study the cytoprotective effects of a diet enriched in glutamine, TGF‐β, and SFCAs (Modulen) in Fischer 344 rats exposed to MTX.

Methods:

Rats were divided into five groups: two receiving normal saline and three receiving MTX and fed either normal chow, Modulen supplemented chow starting with the first MTX dose, or Modulen supplemented chow beginning 3 days before MTX injection. Rats were weighed daily. On day 5, albumin and bicarbonate levels were drawn, and rats were killed for examination of their intestinal mucosa by a pathologist unaware of groupings.

Results:

Rats pretreated with Modulen supplemented chow maintained weight (2.6 vs, 12.3 g weight loss), albumin levels (3.13 vs, 2.43 mg/dL), and bicarbonate levels (23.8 vs. 18.1 mg/dL) as compared with rats fed normal chow throughout MTX treatment (P < 0.05). Pretreatment with Modulen also protected against crypt cell loss, villus atrophy, crypt abscesses, crypt/villus ratio, and overall histologic damage (P < 0.05).

Conclusion:

When administered before and during MTX treatment, Modulen supplementation provided statistically significant protection against weight loss, hypoalbuminemia, acidosis, and GI damage in a rat model. Future animal research of Modulen's protective effects with other chemotherapeutic agents is needed before human trials.
Eradication of Small Intestinal Bacterial Overgrowth in the Cystic Fibrosis Mouse Reduces Mucus Accumulation
Authors: De Lisle Robert C , Roach Eileen A , Norkina Oxana
Published: December 2005

Objectives:

Mucus accumulation in cystic fibrosis (CF) is involved in blockage of the distal small intestine. Because expression of mucin genes and mucus secretion can be increased by infection and previous work indicated that small intestinal bacterial overgrowth occurs in CF, we tested whether reduction of bacterial load by antibiotic treatment would reduce mucin gene expression and mucus accumulation in the CF mouse small intestine.

Methods:

CF transmembrane conductance regulator null (cftrtm1UNC) and wild type littermates were treated with ciprofloxacin and metronidazole for 3 weeks. Muc2 and Muc3 gene expression were measured by quantitative reverse‐transcriptase polymerase chain reaction. Periodic acid Schiff (PAS) staining and morphometry were used to measure the size of mucus droplets within goblet cells and dilation of the intestinal crypt lumen, as estimates of mucus secretion and accumulation.

Results:

Antibiotic treatment did not significantly affect Muc2 and Muc3 gene expression in CF mice. In untreated CF mice, the crypt lumen was almost sevenfold wider than wild type. Antibiotic treatment of CF mice reduced the intensity of PAS crypt lumen staining, and the lumen width was decreased by approximately 25%. The area occupied by PAS‐positive material in goblet cells was significantly greater in tissues from antibiotic treated mice.

Conclusions:

Eradication of bacterial overgrowth in CF mice significantly decreased mucus secretion and accumulation in intestinal crypts without an effect on mucin gene expression. It is proposed that bacterial overgrowth stimulates mucus secretion, which contributes to its accumulation in the small intestine. Control of bacterial overgrowth is expected to reduce mucus accumulation and may improve intestinal function and overall health in CF.
Outcome after Portoenterostomy in Biliary Atresia: Pivotal Role of Degree of Liver Fibrosis and Intensity of Stellate Cell Activation
Authors: Shteyer Eyal , Ramm Grant A , Xu Chunxia , White Frances V , Shepherd Ross W
Published: December 2005

Objectives:

Biliary atresia (BA), a congenital idiopathic obliterative cholangiopathy, rapidly leads to liver cirrhosis and liver failure if untreated. A timely Kasai portoenterostomy (KP) variably alters this natural history. We evaluated liver fibrogenesis by the intensity of α‐smooth‐muscle actin (SMA) expression, which is a marker for hepatic stellate cell activation. We hypothesized that liver fibrogenesis as determined by intensity of α‐SMA is already progressing at the time of KP, is related to age and degree of fibrosis at KP, and predicts outcome after KP.

Methods:

BA patients at KP (n = 22, age 22‐84 days, median 59) had wedge liver biopsies assessed by quantitative morphometry of immunohistochemistry for α‐SMA expression. Fibrosis was scored by blinded pathologists. Outcome, reflected by conjugated bilirubin concentration 3 months after KP (CBili3m), survival of the native liver, need for liver transplant, or death, were assessed for 2 to 10 years after KP.

Results:

At KP, age, fibrosis score, and α‐SMA expression were significantly correlated. Moderate‐severe fibrosis and intense α‐SMA expression was observed in 15 of 22 (68%) patients. Severe fibrosis and high α‐SMA expression were significantly associated with CBili3m greater than 2 g/dL and unfavorable liver survival (>90% of these ultimately underwent liver transplantation or died). Conversely, those with mild fibrosis and low α‐SMA expression had normal CBili3m and favorable liver survival.

Conclusion:

Intense liver fibrogenesis is already established in many cases of BA at the time of KP. Fibrosis scores and intensity of α‐SMA expression may be predictors of outcome after KP and may indicate those patients who might benefit from trials of potential antifibrotic agents early in the course of BA.
Genetic Polymorphisms of CD14, Toll‐like Receptor 4, and Caspase‐Recruitment Domain 15 Are Not Associated with Necrotizing Enterocolitis in Very Low Birth Weight Infants
Authors: Szebeni Beáta , Szekeres Roxána , Rusai Krisztina , Vannay Ádám , Veres Gábor , Treszl András , Arató András , Tulassay Tivadar , Vásárhelyi Barna
Published: December 2005

Objectives:

Inadequate response of the innate immune system to bacterial antigens present in the intestinal flora may play a role in the development of necrotizing enterocolitis (NEC). Pattern recognition receptors such as CD14, toll‐like receptor (TLR) 4, and caspase‐recruitment domain (CARD) 15 bind bacterial lipopolysaccharide and peptidoglycan, and their activation leads to production of inflammatory cytokines. Our aim was to evaluate whether single nucleotide polymorphisms (SNPs) of CD14, TLR4, and CARD15 are associated with the risk of NEC in very low birth weight (VLBW) infants.

Patients and Methods:

We determined the CD14 C−260T, TLR4 A + 896G, C + 1196T, and CARD15 G + 2722C, C + 2104T, 3020insC functional SNPs in dried blood samples from 118 VLBW infants (of those, 41 developed NEC) and from 146 healthy term newborns using polymerase chain reaction and restriction fragment length polymorphism methods. We tested the association between genotype and risk of NEC.

Results:

No significant differences were found in the prevalence of CD14 −260T, TLR4 +896G, +1196T, and CARD15 +2722C, +2104T, 3020insC alleles between VLBW infants and healthy term newborns (P = NS). The frequencies of investigated genotypes were similar in infants with and without NEC (P = NS). Furthermore, we did not find any association between genotype and prematurity or sepsis, which are important risk factors of NEC.

Conclusions:

Carrier state of the tested CD14, TLR4, and CARD15 SNPs is not associated with NEC risk in VLBW infants.
Positive Association of Macrophage Migration Inhibitory Factor Gene‐173G/C Polymorphism with Biliary Atresia
Authors: Arikan Cigdem , Berdeli Afig , Ozgenc Funda , Tumgor Gokhan , Yagci Rasit V , Aydogdu Sema
Published: December 2005

Background:

Macrophage migration inhibitory factor (MIF) is a pleiotrophic lymphocyte and macrophage cytokine; it is likely to play an important role in innate immunity. Its expression was increased in several inflammatory diseases, and MIF gene polymorphisms have an effect on disease outcome and response to glucocorticoid treatment.

Aim:

To investigate the role of the 173G/C polymorphism of the MIF gene for susceptibility to biliary atresia (BA).

Method:

Between February 2002 and November 2004, 18 patients (mean age 1 ± 0.4 years) diagnosed as having BA were studied. After informed consent, blood was collected, and DNA was obtained. MIF 173C/G polymorphism was detected using the polymerase chain reaction‐restriction fragment length polymorphism based method. BA patients were compared with a group of chronic liver disease patients (CLD) (n = 36) and a group of unrelated healthy controls (n = 103).

Results:

MIF‐173C allele frequency was significantly higher than both the CLD and healthy control groups (P = 0.03, odds ratio [OR] 4.4, 95% confidence interval [CI] 1.3‐15.1; P = 0.000, OR 4.1, 95% CI 2.3‐7.6, respectively). Univariate analysis showed that MIF‐173G/C polymorphism was significantly associated with BA (for GC genotype, OR = 6, 95 % CI 2.8‐11.5, P = 0.000). There was no significant correlation between pediatric end stage liver disease score and MIF genotypes both in BA and CLD groups.

Conclusion:

Our results suggest that the ‐173C allele of the MIF gene might be associated with the susceptibility to BA.
ATP‐sensitive K+ channels: regulation of bursting by the sulphonylurea receptor, PIP2 and regions of Kir6.2
Authors: Ribalet Bernard , John Scott A. , Xie Lai‐Hua , Weiss James N.
Published: December 2005

ATP‐sensitive K+ channels composed of the pore‐forming protein Kir6.2 and the sulphonylurea receptor SUR1 are inhibited by ATP and activated by Phosphatidylinositol Bisphosphate (PIP2). Residues involved in binding of these ligands to the Kir6.2 cytoplasmic domain have been identified, and it has been hypothesized that gating mechanisms involve conformational changes in the regions of the bundle crossing and/or the selectivity filter of Kir6.2. Regulation of Kir6.2 by SUR1, however, is not well‐understood, even though this process is ATP and PIP2 dependent. In this study, we investigated the relationship between channel regulation by SUR1 and PIP2 by comparing a number of single and double mutants known to affect open probability (Po), PIP2 affinity, and sulphonylurea and MgADP sensitivity. When coexpressed with SUR1, the Kir6.2 mutant C166A, which is characterized by a Po value close to 0.8, exhibits no sulphonylurea or MgADP sensitivity. However, when Po was reduced by combining mutations at the PIP2‐sensitive residues R176 and R177 with C166A, sulphonylurea and MgADP sensitivities were restored. These effects correlated with a dramatic decrease in PIP2 affinity, as assessed by PIP2‐induced channel reactivation and inhibition by neomycin, an antagonist of PIP2 binding. Based on macroscopic and single‐channel data, we propose a model in which entry into the high‐Po bursting state by the C166A mutation or by SUR1 depends on the interaction of PIP2 with R176 and R177 and, to a lesser extent, R54. In conjunction with this PIP2‐dependent process, SUR1 also regulates channel activity via a PIP2‐independent, but MgADP‐dependent process.
Are You Really Psychic?
Authors: Blanton Patricia
Published: December 2005

The thing I love most about teaching science is that just about anything that happens provides an opportunity to encourage students to observe, question, examine, analyze, synthesize, and draw conclusions. I was reminded of this recently when an email I received from a colleague turned into a scientific inquiry adventure for students. The subject line on the email was Freaky Friday Fun and in the body of the message was the web address http://trunks.second foundation.org/files/psychic.swf. Clicking on the link took me to a page called “The Flash Mind Reader,” created by Andy Naughton. The instructions tell you to choose any two-digit number, add both digits together, and then subtract that total from the original number. Then you are told to look at the chart of numbers and associated symbols, find your final number, concentrate on the symbol associated with that number, get it clearly in your mind, and then click on the crystal ball and your symbol will appear.
Tapping Into Renewal
Authors: Leslie Mitch
Published: December 2005

Unlock your latent abilities, and you could have abs of steel or make a fortune in real estate--or so the late-night infomercials promise. Hyped sales pitches aside, plugging into underutilized talents could help the brain resist the devastation of Huntington's disease. A new study shows that cranking up the organ's capacity to produce neurons delays the disease's progress in mice. The work could lead to a therapy for this untreatable illness.
Novel Gyrase Mutations in Quinolone-Resistant and -Hypersusceptible Clinical Isolates of
Mycobacterium tuberculosis
: Functional Analysis of Mutant Enzymes
Authors: Aubry Alexandra , Veziris Nicolas , Cambau Emmanuelle , Truffot-Pernot Chantal , Jarlier Vincent , Fisher L. Mark
Published: December 2005

Mutations in the DNA gyrase GyrA
2
GyrB
2
complex are associated with resistance to quinolones in
Mycobacterium tuberculosis
. As fluoroquinolones are being used increasingly in the treatment of tuberculosis, we characterized several multidrug-resistant clinical isolates of
M. tuberculosis
carrying mutations in the genes encoding the GyrA or GyrB subunits associated with quinolone resistance or hypersusceptibility. In addition to the reported putative quinolone resistance mutations in GyrA, i.e., A90V, D94G, and D94H, we found that the GyrB N510D mutation was also associated with ofloxacin resistance. Surprisingly, several isolates bearing a novel combination of
gyrA
T80A and A90G changes were hypersusceptible to ofloxacin.
M. tuberculosis
GyrA and GyrB subunits (wild type [WT] and mutants) were overexpressed in
Escherichia coli
, purified to homogeneity, and used to reconstitute highly active gyrase complexes. Mutant proteins were produced similarly from engineered
gyrA
and
gyrB
alleles by mutagenesis. MICs, enzyme inhibition, and drug-induced DNA cleavage were determined for moxifloxacin, gatifloxacin, ofloxacin, levofloxacin, and enoxacin. Mutant gyrase complexes bearing GyrA A90V, D94G, and D94H and GyrB N510D were resistant to quinolone inhibition (MICs and 50% inhibitory concentrations [IC
50
s] at least 3.5-fold higher than the concentrations for the WT), and all, except the GyrB mutant, were less efficiently trapped as a quinolone cleavage complex. In marked contrast, gyrase complexes bearing GyrA T80A or A90G were hypersusceptible to the action of many quinolones, an effect that was reinforced for complexes bearing both mutations (MICs and IC
50
s up to 14-fold lower than the values for the WT). This is the first detailed enzymatic analysis of hypersusceptibility and resistance in
M. tuberculosis
.
Two Cathelicidin Genes Are Present in both Rainbow Trout (
Oncorhynchus mykiss
) and Atlantic Salmon (
Salmo salar
)
Authors: Chang Chin-I , Zhang Yong-An , Zou Jun , Nie Pin , Secombes Christopher J.
Published: December 2005

Further to the previous finding of the rainbow trout
rt
CATH_1 gene, this paper describes three more cathelicidin genes found in salmonids: two in Atlantic salmon, named
as
CATH_1 and
as
CATH_2, and one in rainbow trout, named
rt
CATH_2. All the three new salmonid cathelicidin genes share the common characteristics of mammalian cathelicidin genes, such as consisting of four exons and possessing a highly conserved preproregion and four invariant cysteines clustered in the C-terminal region of the cathelin-like domain. The
as
CATH_1 gene is homologous to the rainbow trout
rt
CATH_1 gene, in that it possesses three repeat motifs of TGGGGGTGGC in exon IV and two cysteine residues in the predicted mature peptide, while the
as
CATH_2 gene and
rt
CATH_2 gene are homologues of each other, with 96% nucleotide identity. Salmonid cathelicidins possess the same elastase-sensitive residue, threonine, as hagfish cathelicidins and the rabbit CAP18 molecule. The cleavage site of the four salmonid cathelicidins is within a conserved amino acid motif of QKIRTRR, which is at the beginning of the sequence encoded by exon IV. Two 36-residue peptides corresponding to the core part of
rt
CATH_1 and
rt
CATH_2 were chemically synthesized and shown to exhibit potent antimicrobial activity.
rt
CATH_2 was expressed constitutively in gill, head kidney, intestine, skin and spleen, while the expression of
rt
CATH_1 was inducible in gill, head kidney, and spleen after bacterial challenge. Four cathelicidin genes have now been characterized in salmonids and two were identified in hagfish, confirming that cathelicidin genes evolved early and are likely present in all vertebrates.
In Vivo and In Vitro Studies of Antibiotic Release from and Bacterial Growth Inhibition by Antibiotic-Impregnated Polymethylmethacrylate Hip Spacers
Authors: Kelm Jens , Regitz Thilo , Schmitt Eduard , Jung Werner , Anagnostakos Konstantinos
Published: December 2005

The antimicrobial properties and the elution characteristics of gentamicin-vancomycin-loaded hip spacers were studied in vivo and in vitro. Vancomycin elution was greater than gentamicin elution. The antibiotic concentrations in vivo were less than those in vitro. Not dependent on implantation duration, growth inhibition by spacers in vitro was observed for 2 weeks. The reason for protracted wound healing cannot be insufficient antibiotic release.
Anucleate Cell Blue Assay: a Useful Tool for Identifying Novel Type II Topoisomerase Inhibitors
Authors: Oyamada Yoshihiro , Ito Hideaki , Fujimoto-Nakamura Mika , Tanitame Akihiko , Iwai Noritaka , Nagai Kazuo , Yamagishi Jun-ichi , Wachi Masaaki
Published: December 2005

About 95,000 compounds were screened by the anucleate cell blue assay. Fifty-one of the hit compounds had various structures and showed inhibitory activity against DNA gyrase and/or topoisomerase IV. Moreover, the compounds exhibited antibacterial activity against a fluoroquinolone- and novobiocin-resistant strain of
Staphylococcu
s
aureus
. The anucleate cell blue assay is therefore a useful tool for finding novel type II topoisomerase inhibitors.
Heterogeneous Macrolide Resistance and Gene Conversion in the Pneumococcus
Authors: Wolter Nicole , Smith Anthony M. , Farrell David J. , Klugman Keith P.
Published: December 2005

A macrolide-resistant clinical isolate of
Streptococcus pneumoniae
with 23S rRNA mutations showed a heterogeneous phenotype and genotype. The mutant 23S rRNA genes from this isolate transformed susceptible strain R6 to resistance. Culture of resistant strain R6 in the absence of antibiotic pressure showed gene conversion to occur between the four 23S rRNA alleles, resulting in reversion to susceptibility with the resistant phenotype showing a fitness cost. These data explain the disappearance on subculture of heterogeneous macrolide resistance in the pneumococcus.
Clonal Dissemination and
mupA
Gene Polymorphism of Mupirocin-Resistant
Staphylococcus aureus
Isolates from Long-Term-Care Facilities in South Korea
Authors: Yoo Jae Il , Shin Eun Shim , Cha Jeong Ok , Lee Jeom Kyu , Jung Young Hee , Lee Kyeong Min , Kim Bong Su , Lee Yeong Seon
Published: December 2005

We identified 25 high-level mupirocin-resistant (MuH) and 21 low-level mupirocin-resistant (MuL)
Staphylococcus aureus
isolates from eight long-term-care facilities (LTCFs). The pulsed-field gel electrophoresis patterns of 19 MuH and 19 MuL isolates from two facilities were identical for 18 and 15 isolates, respectively. The most predominant
mupA
restriction fragment length polymorphism type was found in 21 MuH isolates. We conclude that clonal transmission of MuH and MuL
S. aureus
strains occurred in these LTCFs. This is the first report of clonal transfer of mupirocin resistance in LTCFs.
In Vitro Activity of Fosfomycin against Extended-Spectrum-β-Lactamase- Producing
Escherichia coli
and
Klebsiella pneumoniae
: Comparison of Susceptibility Testing Procedures
Authors: de Cueto M. , López L. , Hernández J. R. , Morillo C. , Pascual A.
Published: December 2005

The agar dilution, broth microdilution, and disk diffusion methods were compared to determine the in vitro susceptibility of 428 extended-spectrum-β-lactamase (ESBL)-producing
Escherichia coli
and
Klebsiella pneumoniae
to fosfomycin. Fosfomycin showed very high activity against all ESBL-producing strains. Excellent agreement between the three susceptibility methods was found for
E. coli
, whereas marked discrepancies were observed for
K. pneumoniae
.
Involvement of the Drug Transporters P Glycoprotein and Multidrug Resistance-Associated Protein Mrp2 in Telithromycin Transport
Authors: Yamaguchi Shoji , Zhao Ying Lan , Nadai Masayuki , Yoshizumi Hideo , Cen Xiaobo , Torita Shoko , Takagi Kenji , Takagi Kenzo , Hasegawa Takaaki
Published: December 2005

The present study aims to investigate the role of P glycoprotein and multidrug resistance-associated protein (Mrp2) in the transport of telithromycin, a newly developed ketolide antibiotic, in vitro and in vivo. The in vitro experiments revealed that the intracellular accumulation of telithromycin in adriamycin-resistant human chronic myelogenous leukemia cells (K562/ADR) overexpressing P glycoprotein was significantly lower than that in human chronic myelogenous leukemia cells (K562/S) not expressing P glycoprotein. Cyclosporine significantly increased the intracellular accumulation of telithromycin in K562/ADR cells. When telithromycin was coadministered intravenously with cyclosporine in Sprague-Dawley (SD) rats, cyclosporine significantly delayed the disappearance of telithromycin from plasma and decreased its systemic clearance to 60% of the corresponding control values. Hepatobiliary excretion experiments revealed that cyclosporine almost completely inhibited the biliary clearance of telithromycin, suggesting that telithromycin is a substrate of P glycoprotein and a potential substrate of Mrp2. Moreover, the biliary clearance of telithromycin was significantly decreased by 80% in Eisai hyperbilirubinemic mutant rats with a hereditary deficiency in Mrp2, indicating that Mrp2, as well as P glycoprotein, plays an important role in the biliary excretion of telithromycin. When the effect of telithromycin on the biliary excretion of doxorubicin, a substrate of P glycoprotein and Mrp2, was examined in SD rats, telithromycin significantly decreased the biliary clearance of doxorubicin by 80%. Results obtained from this study indicate that telithromycin is a substrate of both P glycoprotein and Mrp2, and these transporters are involved in the hepatobiliary transport of telithromycin.
From Beaker Chemistry to Programmable Microfluidics
Authors: Ruzicka Jaromir
Published: December 2005

Solution handling is one of the most frequently performed laboratory tasks. In an analytical laboratory, it is also the most exacting and laborious one, as solutions have to be precisely metered, well-mixed, incubated, heated or separated, and finally monitored in a reproducible way, using spectroscopy, electrochemistry or other means for quantification of target analytes. This review with 65 references follows the development of solution handling techniques from manual to mechanized, and into a microfluidic format. It documents the superior versatility of programmable flow, as it is applied to a wide variety of instrumental assays ranging from biochemical to trace analysis of elements. All types of flow injection analysis (FIA) are reviewed, including flow injection (FI), sequential injection (SI), bead injection (BI), and sequential injection chromatography (SIC).
Unperturbed Dimensions of Atactic Poly(phenylacetylene)
Authors: Rédrová Dana , Sedláček Jan , Žigon Majda , Vohlídal Jiří
Published: December 2005

Dilute solution characteristics of atactic (ca. 30% trans) poly(phenylacetylene), PPA, were determined by using the SEC/MALS technique in order to obtain a deeper insight into discrepancy between presumed rigidity of conjugated polyvinylene molecules and their random-coil behavior in solutions resulting from earlier viscometry measurements. PPA was found to exhibit the molecular-weight dependence of the radius of gyration in tetrahydrofuran solution similar to that of atactic polystyrene (saturated analogue of PPA); also unperturbed dimensions of these polymers are almost equal. This rather surprising observation is explained as a consequence of the increased π-π attraction between highly polarizable PPA segments with well-delocalized π-electrons, which compensates the effect of stiffening of these segments due to conjugation. Possible influence of chain branching is also discussed.
Micro/Mesoporous Composites Based on Colloidal Zeolite Grown in Mesoporous Matrix
Authors: Prokešová Pavla , Petkov Nikolay , Čejka Jiří , Mintova Svetlana , Bein Thomas
Published: December 2005

Composite materials containing micro- and mesopores are prepared under instantaneous hydrothermal treatment of initial solutions generally used for zeolite Beta and precursor solutions for mesoporous Al-MCM-41 material. The resulting composites are compared with pure, highly crystalline colloidal microporous Beta zeolite and hexagonally ordered mesostructured samples. The porosity and morphological features of the composite materials are influenced by the conditions of hydrothermal synthesis of the initial colloidal solutions used for the preparation of Beta seeds, as well as by the conditions of the synchronized crystallization of the final composites. The embedding of Beta seeds in the mesoporous silica matrix is possible via immediate heating of mesoporous precursor solutions with Beta seeds primarily formed. The composite materials contain either microcrystalline Beta nanodomains with sizes of about 5-10 nm surrounded by mesoporous material or defined Beta nanocrystals (20-40 nm), and at the same time connected with mesostructured material. The presence of highly crosslinked silicate framework walls and tetrahedrally coordinated aluminum in the composite material are confirmed by solid-state 29Si and 27Al MAS NMR spectroscopy. The concentration of Brønsted acid sites in the micro/mesoporous composites is increased substantially in comparison with pure mesoporous Al-MCM-41 material proven by FTIR acetonitrile-d3 adsorption study.
The Synthesis of 10-Halo-Substituted Derivatives of nido-7,8,9-PC2B8H11 and [nido-7,8,9-PC2B8H10]- and New Linear Correlations Between NMR Parameters
Authors: Holub Josef , Bakardjiev Mario , Štíbr Bohumil
Published: December 2005

Halogenation of the eleven-vertex phosphadicarbaborane nido-7,8,9-PC2B8H10 (1) with CCl4, Br2 or I2 in the presence of anhydrous AlCl3 (solvents CCl4, CS2, and benzene, respectively) generated a series of 10-X-nido-7,8,9-PC2B8H10 (10-X-1) compounds (X = Cl, Br, and I) in yields 55, 65, and 63%, respectively. Anionic compounds [10-X-nido-7,8,9-PC2B8H10]- (10-X-2) (X = Cl, Br, I) were obtained by treatment of the corresponding neutral compounds with "proton sponge" (PS = 1,8-bis(dimethylamino)naphthalene). All compounds were characterized by multinuclear (11B, 1H, and 31P) NMR spectroscopy and [11B-11B]-COSY and 1H-{11B(selective)} NMR measurements that led to complete assignments of all 11B and 1H resonances to individual cluster positions. Interesting halo-substitution NMR effects are also discussed in terms of new linear correlations. All the changes in NMR chemical shifts (∆) induced at the various skeletal sites by halogeno substituents on specific sites can be related to an arbitrary reference skeleton and are, within experimental errors, linearly proportional to those induced at the substituted site (∆α) of the reference skeleton.
Sulfoxide-Modified Julia-Lythgoe Olefination: Highly Stereoselective Di-, Tri-, and Tetrasubstituted Double Bond Formation
Authors: Pospíšil Jiří , Pospíšil Tomáš , Markó István E.
Published: December 2005

A novel modification of the classical Julia-Lythgoe olefination, using sulfoxides instead of sulfones, affords, after in situ benzoylation and SmI2/HMPA or SmI2/DMPU-mediated reductive elimination, 1,2-di-, tri- and tetrasubstituted olefins in moderate to good yields and E/Z selectivity. The conditions are mild and the procedure is widely applicable. The reaction mechanism was studied and a general model, describing the reaction selectivity, is proposed.
DETECTION AND COMPENSATION ALGORITHM FOR BACKLIGHT IMAGES WITH FUZZY LOGIC AND ADAPTIVE COMPENSATION CURVE
Authors: CHIN CHIUN-LI , LIN CHIN-TENG
Published: December 2005

This paper presents a new algorithm for detection and compensation of backlight images. The proposed technique attacks the weakness of the conventional backlight image processing methods such as over-saturation, losing contrast and so on. The proposed algorithm consists of two operation phases: detection and compensation phases. In the detection phase, we use the spatial position characteristic and histogram of backlight image to obtain two image indices, which can determine the backlight degree of an image. Fuzzy logic is then used to integrate these two indices into a final backlight index determining the final backlight degree of an image precisely. Second, in the compensation phase, to solve the over-saturation problem that exists usually in conventional image compensation methods, we propose the adaptive compensation-curve scheme to compensate and enhance the brightness of backlight images. The luminance of a backlight image is adjusted according to the compensation curve, which is adapted dynamically according to the backlight degree indicated by the backlight index estimated in the detection phase. The performance of the proposed technique is tested on 100 backlight images covering various kinds of backlight conditions and degrees. The experimental and comparison results clearly show the superiority of the proposed technique.
A SEQUENTIAL BAYESIAN ALGORITHM FOR SURVEILLANCE WITH NONOVERLAPPING CAMERAS
Authors: ZAJDEL WOJCIECH , KRÖSE BEN J. A.
Published: December 2005

Visual surveillance in wide areas (e.g. airports) relies on sparsely distributed cameras, that is, cameras that observe nonoverlapping scenes. In this setup, multiobject tracking requires reidentification of an object when it leaves one field of view, and later appears at some other. Although similar association problems are common for multiobject tracking scenarios, in the distributed case one has to cope with asynchronous observations and cannot assume smooth motion of the objects. In this paper, we propose a method for human indoor tracking. The method is based on a Dynamic Bayes Network (DBN) as a probabilistic model for the observations. The edges of the network define the correspondences between observations of the same object. Accordingly, we derive an approximate EM-like method for selecting the most likely structure of DBN and learning model parameters. The presented algorithm is tested on a collection of real-world observations gathered by a system of cameras in an office building.
QUARK STARS AND QUANTUM-MAGNETICALLY INDUCED COLLAPSE
Authors: PÉREZ MARTÍNEZ A. , PÉREZ ROJAS H. , MOSQUERA CUESTA H. J. , BOLIGAN M. , ORSARIA M. G.
Published: December 2005

Quark matter is expected to exist in the interior of compact stellar objects as neutron stars or even the more exotic strange stars, based on the Bodmer–Witten conjecture. Bare strange quark stars and (normal) strange quark-matter stars, those possessing a baryon (electron-supported) crust, are hypothesized as good candidates to explain the properties of a set of peculiar stellar sources such as the enigmatic X-ray source RX J1856.5-3754, some pulsars such as PSR B1828-11 and PSR B1642-03, and the anomalous X-ray pulsars and soft γ-ray repeaters. In the MIT bag model, quarks are treated as a degenerate Fermi gas confined to a region of space having a vacuum energy density B bag (the Bag constant). In this note, we modify the MIT bag model by including the electromagnetic interaction. We also show that this version of the MIT model implies the anisotropy of the bag pressure due to the presence of the magnetic field. The equations of state of the degenerate quarks gases are studied in the presence of ultra strong magnetic fields. The behavior of a system made up of quarks having (or not) anomalous magnetic moment is reviewed. A structural instability is found, which is related to the anisotropic nature of the pressures in this highly magnetized matter. The conditions for the collapse of this system are obtained and compared to a previous model of neutron stars that is built on a neutron gas having anomalous magnetic moment.
STATEFINDER PARAMETERS FOR QUINTOM DARK ENERGY MODEL
Authors: WU PUXUN , YU HONGWEI
Published: December 2005

We perform in this paper a statefinder diagnostic to a dark energy model with two scalar fields, called "quintom," where one of the scalar fields has a canonical kinetic energy term and the other has a negative one. Several kinds of potentials are discussed. Our results show that the statefinder diagnostic can differentiate quintom model with other dark energy models.
COLLAPSING NEUTRON STARS DRIVEN BY CRITICAL MAGNETIC FIELDS AND EXPLODING BOSE–EINSTEIN CONDENSATES
Authors: PÉREZ ROJAS H. , PÉREZ MARTÍNEZ A. , MOSQUERA CUESTA HERMAN J.
Published: December 2005

A Bose–Einstein condensate of a neutral vector boson bearing an anomalous magnetic moment is suggested as a model for ferromagnetic origin of magnetic fields in neutron stars. The vector particles are assumed to arise from parallel spin-paired neutrons. A negative pressure perpendicular to the external field B is acting on this condensate, which for large densities, compress the system, and may produce a collapse. An upper bound of the magnetic fields observable in neutron stars is given. In the the non-relativistic limit, the analogy with the behavior of exploding Bose–Einstein condensates (BECs) for critical values of the magnetic field is briefly discussed.
SYNTHESIS AND CHARACTERIZATION OF LONG-ALKYL CHAINED CARBAZOLE DERIVATIVES
Authors: HWANG EUN JEE , BAE SANG HEE , LEE JI HOON , KIM TAE WAN , PARK JONG WOOK
Published: December 2005

We have synthesized N-alkylated carbazole with a variation of alkyl size such as ethyl, hexyl, dodecyl and octadecyl group and have made thin film by using the spin-coating method. When N -octadecyl carbazole (NOC) film is made on ITO, the surface of the ITO/NOC layer becomes flatter compared to ITO and ITO/other N -alkylated carbazole layer. As the pendent alkyl chain length of carbazole becomes longer, the PL spectrum of the carbazole derivative becomes smooth and the PL maximum value is slightly shifted to long wavelength. ITO/NOC (100 nm)/ LiF (1 nm)/Al (200 nm) device showed typical I-V characteristics and very weak blue EL light.
SYNTHESIS AND ELECTROLUMINESCENT PROPERTY OF ALUMINUM AND α-PYRIDOIN COMPLEX
Authors: KIM WON SAM , LIM JONG HAN , LEE BURM-JONG , OH YUNGHEE , KWON YOUNG-SOO
Published: December 2005

A novel light-emitting aluminum complex (PAl) containing the dihydroxy derivative of trans-1,2-dipyridylethene, α-pyridoin, was synthesized and its electroluminescent (EL) properties characterized. The chemical structure of the complex was elucidated by FT-IR, UV-Vis and XPS. The complex showed thermal stability up to 350°C under nitrogen flow by TGA. The photoluminescence (PL) was measured from PAl cast film on quartz plate. Electroluminescent device having the structure of ITO/TPD/PAl/Al was fabricated by vacuum deposition, where N,N-bis(3-methylphenyl)-N,N′-diphenylbenzidine (TPD) was used as a hole transporting layer. The device emitted blue-green light of around 480 nm. The maximum luminance of 38 cd/m2 and current density of 0.09 mA/cm2 were observed at 34 V.
COMPLEXATION OF AROMATIC MOLECULES WITH NEW CALIXARENE DERIVATIVES CONTAINING TWO ARYL SULFIDE RINGS
Authors: SHIN DONG-MYUNG , SONG DONG-MEE , CHUNG GEEWON , KIM KYEONGTAE
Published: December 2005

The cuplike structure of calix[4]arenes is one of the most attractive features, which has been observed both in the solid state and in solution. The newly synthesized 5,11,17,23-tetrakis(3-mercaptopropyl)calix[4]arene (1) and 25,26,27,28-tetrakis(5-mercaptopenthoxy)calix[4]arene containing aryl sulfide rings (2), have four alkyl thiol linkages, which allow the calixarenes to attach onto the gold surface. Surface plasmon resonance (SPR) spectroscopy allows us to monitor the binding of calixarene derivatives on the gold surface. The 1 and 2 bind very effectively on the gold surface and self-assembled layers of 1 and 2 produce significant change in SPR signals in 30 min. Calixarenes layers are used as platforms for molecular recognition, where complementary binding sites are easily and selectively introduced. The aromatic molecules used in this study are anthracene, pyrene, coronene and rubrene. The host-guest properties of these aromatic molecules and the calixarene cavity exhibit selectivity of these aromatic molecules. The anthracene, pyrene and coronene have moderate binding affinity to the cavity, and the rubrene does not bind at all.
PREPARATION OF PANEL AND CHARGED PARTICLES FOR ELECTROPHORETIC DISPLAY
Authors: CHOI HYUNG SUK , PARK JIN WOO , PARK LEE SOON , LEE JUNG KYUNG , HAN YOON SOO , KWON YOUNGHWAN
Published: December 2005

Studies on the formulation of photosensitive paste for transparent soft mold press (TSMP) method have been performed. With the optimum formulation of the photosensitive paste the box-type barrier rib with good flexibility and high solvent resistance was fabricated, suitable for the panel material of the electrophoretic display. Cationically-charged white particles were prepared by using TiO2 nanoparticles, silane coupling agent with amino groups, dispersant and acetic acid. The cationically charged TiO2 particles exhibited 74.09 mV of zeta potential and 3.11 × 10-5 cm2/Vs of mobility. Electrophoretic display fabricated with the charged TiO2 particles exhibited 10 V of low driving voltage and maximum contrast ratio (5.3/1) at 30 V.
SYNTHESIS AND ELECTROLUMINESCENT PROPERTIES OF POLYAZOMETHINE-TYPE CONJUGATED POLYMERS CONTAINING HETEROCYCLIC PHENOTHIAZINE AND CARBAZOLE MOIETY
Authors: JEONG JEON WOO , KWON YOUNGHWAN , BAEK JEONG JU , PARK LEE SOON , LEE EUI-WAN , HAN YOON SOO , KIM HONG TAK
Published: December 2005

Polyazomethine-type conjugated polymers were synthesized by Schiff-base reaction. One was poly(PZ-PBI) with alternating phenothiazine (PZ) and azomethine units (-C = N-) , and the other was poly(CZ-PBI) comprising alternating carbazole (CZ) and azomethine groups. Conjugated polymers exhibited improved solubility in common organic solvents due to alkyl side chains on phenothiazine and carbazole rings as well as polar azomethine groups in main chains. Single- and double-layer PLEDs were fabricated. Their electroluminescent properties were studied from the viewpoint of polymer structure vs. emission color and efficiency.
DISCRIMINATION OF PATHOLOGICAL CASES OF THE CARDIACS SOUNDS SIGNALS BY THE WAVELET TRANSFORM
Authors: DEBBAL S. M. , BEREKSI-REGUIG F.
Published: December 2005

In order to highlight the cardiac sounds or phonocardiogram (PCG) signals analysis according to their added murmur importance, we try to apply the wavelet transform in its multi resolution analysis version. We then look for reconstruction error between the original signal and the synthesized signal. In this case, the original PCG signal is decomposed over seven levels and the seventh detail of decomposition is considered as the synthesized signal. According to the results we obtain, the reconstruction error can be considered as an important parameter in the classification and discrimination of the pathological severity of the PCG signals.
AN ALGORITHM TO CALCULATE THE COMPONENTS OF ALL MUSCLE FORCES DURING EACH PHASES OF THE GAIT CYCLE, FOR THE PELVIC-FEMUR COMPLEX
Authors: MAJUMDER SANTANU , ROYCHOWDHURY AMIT , PAL SUBRATA
Published: December 2005

With the help of finite element (FE) computational models of femur, pelvis or hip joint to perform quasi-static stress analysis during the entire gait cycle, muscle force components (X, Y, Z) acting on the hip joint and pelvis are to be known. Most of the investigators have presented only the net muscle force magnitude during gait. However, for the FE software, either muscle force components (X, Y, Z) or three angles for the muscle line of action are required as input. No published algorithm (with flowchart) is readily available to calculate the required muscle force components for FE analysis. As the femur rotates about the hip center during gait, the lines of action for 27 muscle forces are also variable. To find out the variable lines of action and muscle force components (X, Y, Z) with directions, an algorithm was developed and presented here with detailed flowchart. We considered the varying angles of adduction/abduction, flexion/extension during gait. This computer program, obtainable from the first author, is able to calculate the muscle force components (X, Y, Z) as output, if the net magnitude of muscle force, hip joint orientations during gait and muscle origin and insertion coordinates are provided as input.
NEW ALGORITHM FOR QRS COMPLEX DETECTION
Authors: SLIMANE Z. E. HADJ , BEREKSI REGUIG F.
Published: December 2005

The Electrocardiogram (ECG), represents the electrical activity of the heart. It is characterized by a number of waves P, QRS, T which are correlated to the status of the heart activity. The most predominant wave set is the QRS complex. In this paper, we have developed a new algorithm for the detection of the QRS complexes. The algorithm consists of several steps: signal to noise enhancement, differentiation, first-order backward difference, non linear transform, moving window integrator and QRS detection. This algorithm is tested on ECG signals from the universal MIT-BIH arrhythmia database and compared with Pan and Tompkins' QRS detection method. The results we obtain show that our method performs better than the Pan and Tompkins' method. Our algorithm results in lower false positives and lower false negatives.
Muscle type-specific fatty acid metabolism in insulin resistance: an integrated in vivo study in Zucker diabetic fatty rats
Authors: Beha Anja , Juretschke Hans-Paul , Kuhlmann Johanna , Neumann-Haefelin Claudia , Belz Ulrich , Gerl Martin , Kramer Werner , Roden Michael , Herling Andreas W.
Published: December 2005

Intramyocellular lipid content (IMCL) serves as a good biomarker of skeletal muscle insulin resistance (IR). However, intracellular fatty acid metabolites [malonyl-CoA, long-chain acyl-CoA (LCACoA)] rather than IMCL are considered to be responsible for IR. This study aimed to investigate dynamics of IMCL and fatty acid metabolites during fed-to-starved-to-refed transition in lean and obese (IR) Zucker diabetic fatty rats in the following different muscle types: soleus (oxidative), extensor digitorum longus (EDL, intermediary), and white tibialis anterior (wTA, glycolytic). In the fed state, IMCL was significantly elevated in obese compared with lean rats in all three muscle types (soleus: 304%, EDL: 333%, wTA: 394%) in the presence of elevated serum triglycerides but similar levels of free fatty acids (FFA), malonyl-CoA, and total LCACoAs. During starvation, IMCL in soleus remained relatively constant, whereas in both rat groups IMCL increased significantly in wTA and EDL after comparable dynamics of starvation-induced FFA availability. The decreases of malonyl-CoA in wTA and EDL during starvation were more pronounced in lean than in obese rats, although there were no changes in soleus muscles for both groups. The concomitant increase in IMCL with the fall of malonyl-CoA support the concept that, as a reaction to starvation-induced FFA availability, muscle will activate lipid oxidation more the lower its oxidative capacity and then store the rest as IMCL.
Ileal oxalate absorption and urinary oxalate excretion are enhanced in Slc26a6 null mice
Authors: Freel Robert W. , Hatch Marguerite , Green Mike , Soleimani Manoocher
Published: December 2005

Intestinal oxalate transport, mediated by anion exchange proteins, is important to oxalate homeostasis and consequently to calcium oxalate stone diseases. To assess the contribution of the putative anion transporter (PAT)1 (Slc26a6) to transepithelial oxalate transport, we compared the unidirectional and net fluxes of oxalate across isolated, short-circuited segments of the distal ileum of wild-type (WT) mice and Slc26a6 null mice [knockout (KO)]. Additionally, urinary oxalate excretion was measured in both groups. In WT mouse ileum, there was a small net secretion of oxalate ([Formula: see text]), whereas in KO mice JnetOxwas significantly absorptive (75 ± 10 pmol·cm−2h·h−1), which was the result of a smaller serosal-to-mucosal oxalate flux ( JsmOx) and a larger mucosal-to-serosal oxalate flux ( JmsOx). Mucosal DIDS (200 μM) reduced JsmOxin WT mice, leading to reversal of the direction of net oxalate transport from secretion to absorption ([Formula: see text]) , but DIDS had no significant effect on KO ileum. In WT mice in the absence of mucosal Cl−, there were small increases in JmsOxand decreases in JsmOxthat led to a small net oxalate absorption. In KO mice, JnetOxwas 1.5-fold greater in the absence of mucosal Cl−, due solely to an increase in JmsOx. Urinary oxalate excretion was about fourfold greater in KO mice compared with WT littermates. We conclude that PAT1 is DIDS sensitive and mediates a significant fraction of oxalate efflux across the apical membrane in exchange for Cl−; as such, PAT1 represents a major apical membrane pathway mediating JsmOx.