bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nicotine Decreases Blood Alcohol Concentrations in Adult Rats: A Phenomenon Potentially Related to Gastric Function
Authors: Parnell Scott E. , West James R. , Chen Wei‐Jung A. 
Published: July 2006

Background: In spite of the fact that drinking and smoking often occur together, little is known about the pharmacokinetic interaction between alcohol and nicotine. Previous research in neonatal rats demonstrated that nicotine reduces blood alcohol concentrations (BACs) if alcohol and nicotine are administered simultaneously. However, it is unclear whether such a phenomenon can be observed in adult subjects, given the fact that there is an ontogenetic difference in alcohol metabolism.Methods: A range of nicotine doses (0, 0.25, 0.5, 1, 2, 4, and 6 mg/kg) were administered individually with an alcohol dose (4 g/kg) via intragastric (IG) intubation to adult female rats, and the resultant BACs were measured at various time points following drug administration. Furthermore, the hypothesis that nicotine's role in reducing BACs is mediated through factors related to gastric function was examined by comparing the resultant BACs after an IG intubation or intraperitoneal (IP) injection of alcohol.Results: The results from this study showed significant nicotine dose–related decreases in BACs with 0.5, 1, 2, 4, and 6 mg/kg doses of nicotine at the various time points assessed. This effect, however, occurred only when alcohol was administered via IG intubation, but not after an IP injection of alcohol.Conclusions: These results suggest that the nicotine‐induced decrease in BAC may be related to gastric function. One possible explanation was related to nicotine's action in delaying gastric emptying. The longer the alcohol was retained in the stomach, the more likely that the alcohol would be metabolized by gastric alcohol dehydrogenase before its absorption into the bloodstream by the small intestine (the major site of alcohol absorption).
Nicotine Stimulation on Extracellular Glutamate Levels in the Nucleus Accumbens of Ethanol‐withdrawn Rats In Vivo
Authors: Saellstroem Baum S. , Huebner Anke , Krimphove M. , Morgenstern Rudolf , Badawy Abdulla A.‐B. , Spies Claudia D. 
Published: July 2006

Background: Nicotine can release glutamate in the limbic system. Presynaptic activation of glutamate receptors might be relevant for the subsequent firing of excitatory postsynaptic potentials. This might be relevant in early ethanol withdrawal. The effects and differences of nicotine stimulation on glutamate response measured by microdialysis in the nucleus accumbens (NAC) between ethanol‐withdrawn rats (EW group) and ethanol‐naïve rats (control group) were investigated.Methods: Rats were ethanol‐intoxicated according to a binge‐drinking model: recurrent cycle of 4 days of intoxication (EW group) or 5% sucrose (control group), followed by a 3‐day recovery. This was followed by a 2‐day intoxication period and subsequent abstinence. After the last oral intake, microdialysis was performed in the left NAC for a 16‐hour withdrawal period. At the end of the withdrawal period, a rated withdrawal score (RWS) was documented. Then, nicotine was given subcutaneously at a dose of 0.5 mg/kg and amino acid levels determined by microdialysis were followed for an additional 3 hours.Results: The RWS was not correlated to the last amount of ethanol received, but was correlated to the total amount of ethanol administered during the pretreatment period: the basal values of extracellular glutamate were found to be decreased in the EW group before withdrawal. Cessation of ethanol significantly increased glutamate levels with a peak between 4 and 10 hours after the last oral intake. Sixteen hours after ethanol withdrawal, the same level as in the control group was achieved. Nicotine significantly increased glutamate levels in the NAC of the EW group but not in ethanol‐naïve rats.Conclusions: This study showed that withdrawal of ethanol was associated with an increase in extracellular glutamate levels. Systemic administration of nicotine in vivo produced an increase in extracellular levels of glutamate in the core region of the NAC during ethanol withdrawal. This might be a relevant pathomechanism for increased craving either for alcohol or for nicotine after ethanol withdrawal.
Effects of Ethanol and Acetaldehyde on Reactive Oxygen Species Production in Rat Hepatic Stellate Cells
Authors: Novitskiy Gennadiy , Traore Kassim , Wang Lan , Trush Michael A. , Mezey Esteban 
Published: July 2006

Background: Alcoholism is a common cause of cirrhosis. Hepatic stellate cells are the main source of collagen that ultimately leads to hepatic fibrosis and cirrhosis. Reactive oxygen species (ROS) enhance stellate cell activation and stimulate fibrogenesis. In this study, the acute effects of ethanol (ET) and acetaldehyde (AC) were determined on the production of ROS in isolated rat hepatic stellate cells.Methods: Rat stellate cells were isolated in situ by perfusion of the portal vein and cultured. Hydrogen peroxide (H2O2) was determined by luminol‐derived chemiluminescence (CL), while superoxide anion (O2•−) production was assessed by the fluorescent probe hydroethidine.Results: AC increased the formation of H2O2 and O2•−, and these effects were first detectable at AC concentrations of 5 and 10 μM, respectively, reaching a maximum at 50 to 75 μM. Reduction of glutathione (GSH) synthesis by 1‐buthionine sulfoximide (BSO) or by GSH conjugation with dimethylmaleate (DEM) further enhanced the effects of AC on H2O2 and O2•− formation, while N‐acetylcysteine (NAC) decreased H2O2 and eliminated the enhanced generation of O2•− caused by AC. Raloxifene, which inhibits O2•− production by NAD(P)H oxidase, reduced the effects of AC on H2O2 and O2•− production. ET increased H2O2 or O2•− only in the presence of BSO or DEM.Conclusions: This study shows that concentrations of AC, which occur in vivo after the ingestion of alcoholic beverages, result in the formation of ROS in rat hepatic stellate cells. The increases in ROS are known to activate stellate cells promoting fibrogenesis.
Releasing growth factors from activated human platelets after chitosan stimulation: a possible bio‐material for platelet‐rich plasma preparation
Authors: Shen E‐Chin , Chou Tz‐Chong , Gau Ching‐Hwa , Tu Hsiao‐Pei , Chen Yen‐Teen , Fu Earl 
Published: July 2006

AbstractIntroduction: Thrombin is commonly used for activating the platelets and releasing the growth factors on the application of platelet‐rich plasma (PRP). We have previously reported that chitosan can enhance rabbit platelet aggregation. In this study, the effects of chitosan on the subsequent growth factors release after human platelets activation were examined to evaluate the possibility of chitosan being used as a substitute for thrombin during PRP preparation.Material and methods: Human platelet activation was determined by aggregation, adhesion and α‐granule membrane glycoprotein expression. Platelet aggregation was measured by the turbidimetric method, the adhesion was directly examined on chitosan‐coated glass plates under light microscope and scanning electron microscope (SEM), and the α‐granule membrane glycoprotein was detected by fluorescent isothiocyanate (FITC)‐conjugated anti‐CD61 antibody through flow cytometry. The subsequent epidermal growth factor (EGF), platelet‐derived growth factor (PDGF)‐AB and transforming growth factor (TGF)‐β1 release from platelets were assayed by ELISA after mixing with chitosan.Results: The enhancing effects on the platelet adhesion and the aggregation from chitosan were observed. Under both microscopes, the adhesive platelets on the chitosan‐coated plates were not only greater in number but also earlier in activation than those on the control plates. With flow cytometry, increased glycoprotein IIIa expression in platelets was detected after chitosan treatment. Greater concentrations of growth factors were measured from PRP after chitosan treatment than after the solvent treatment.Conclusion: Because of the observations of growth factors releasing from activated human platelets after chitosan stimulation, we suggest that chitosan may be an appropriate substitute for thrombin in PRP preparation.
Dengue as a cause of acute undifferentiated fever in Vietnam
Authors: Phuong Hoang Lan , de Vries Peter J , Nga Tran TT , Giao Phan T , Hung Le Q , Binh Tran Q , Nam Nguyen V , Nagelkerke Nico , Kager Piet A 
Published: July 2006

Abstract

Background
Dengue is a common cause of fever in the tropics but its contribution to the total burden of febrile illnesses that is presented to primary health facilities in endemic regions such as Vietnam, is largely unknown. We aimed to report the frequency of dengue as a cause of fever in Binh Thuan Province, to describe the characteristics of dengue patients, and analyze the diagnostic accuracy of the health care workers and the determinants of the diagnostic process.

Methods
All patients presenting with acute undifferentiated fever at twelve community health posts and one clinic at the provincial malaria station, Binh Thuan Province, a dengue endemic province in southern Vietnam, were included. Record forms were used to fill in patient and diseases characteristics, pre-referral treatment, signs and symptoms, provisional diagnosis and prescribed treatment, referral and final outcome. Serum samples were collected at first presentation and after 3 weeks for serologic diagnosis.

Results
2096 patients were included from April 2001 to March 2002. All 697 patients with paired serum samples were tested for dengue virus IgM and IgG. Acute dengue was found in 33.6% cases and past dengue virus infections were found in 57.1% cases. Acute primary infections were more common among children under 15 years old than among adults (7.7% vs. 3.5%, p value < 0.001). Younger age significantly predicted acute dengue (RR per increasing year of age (95 % CI): 0.986 (0.975–0.997, p value = 0.014). 48.9% of cases with clinical diagnosis of acute dengue were serologically confirmed and 32.5% of cases without clinical diagnosis of acute dengue were positive by serology after all (OR = 1.981, p value 0.025, 95% CI: 1.079 – 3.635). Tourniquet test was not a predictor for dengue diagnosis.

Conclusion
Dengue is responsible for one third of the fevers presented to the public primary health services in Binh Thuan, southern Vietnam. It presents as a highly unspecific illness and is hardly recognized as a clinical entity by primary physicians.
Redox-mediated bypass of restriction point via skipping of G1pm
Authors: Hoffman Arnold , Greene James J , Spetner Lee M , Burke Michael 
Published: July 2006

Abstract

Background
It is well known that cancer cells bypass the restriction point, R, and undergo uncontrolled cell proliferation.

Hypothesis and evidence
We suggest here that fibrosarcoma cells enter G1ps directly from M, skipping G1pm, hence bypassing R, in response to redox modulation. Evidence is presented from the published literature that demonstrate a shortening of the cycle period of transformed fibroblasts (SV-3T3) compared to the nontransformed 3T3 fibroblasts, corresponding to the duration of G1pm in the 3T3 fibroblasts. Evidence is also presented that demonstrate that redox modulation can induce the CUA-4 fibroblasts to bypass R, resulting in a cycle period closely corresponding to the cycle period of fibrosarcoma cells (HT1080).

Conclusion
The evidence supports our hypothesis that a low internal redox potential can cause fibrosarcoma cells to skip the G1pm phase of the cell cycle.
Analysis of cell-based RNAi screens
Authors: Boutros Michael , Brás Lígia P , Huber Wolfgang 
Published: July 2006

AbstractRNA interference (RNAi) screening is a powerful technology for functional characterization of biological pathways. Interpretation of RNAi screens requires computational and statistical analysis techniques. We describe a method that integrates all steps to generate a scored phenotype list from raw data. It is implemented in an open-source Bioconductor/R package, cellHTS (http://www.dkfz.de/signaling/cellHTS). The method is useful for the analysis and documentation of individual RNAi screens. Moreover, it is a prerequisite for the integration of multiple experiments.
Emerging roles of the Angiopoietin-Tie and the ephrin-Eph systems as regulators of cell trafficking
Authors: Pfaff Dennis , Fiedler Ulrike , Augustin Hellmut G 
Published: July 2006

Abstract
Vascular receptor tyrosine kinases (RTK) have been identified as critical regulatory signaling molecules of developmental and adult vascular morphogenic processes [vascular endothelial growth factor (VEGF) receptors=sprouting; EphB receptors=assembly; Tie2 receptor=maturation and quiescence]. It is intriguing that the same molecules that control the growth of blood and lymphatic vessels play critical roles in the adult to regulate maintenance functions related to vascular homeostasis. VEGF is among the most potent inducers of vascular permeability. The second vascular RTK system, the interaction of paracrine-acting Angiopoietin-1 with its cognate receptor Tie2, acts as an endothelial maintenance and survival-mediating molecular system, which stabilizes the vessel wall and controls endothelial cell quiescence. The third vascular RTK system, the interaction of Eph receptors with their Eph family receptor-interacting protein (ephrin) ligands, transduces positional guidance cues on outgrowing vascular sprouts, which are critical for proper arteriovenous assembly and establishment of blood flow. As such, Eph-ephrin interactions act as an important regulator of cell–cell interactions, exerting propulsive and repulsive functions on neighboring cells and mediating adhesive functions. This review summarizes recent findings related to the roles of the Angiopoietin-Tie and the Eph-ephrin systems as regulators of cell trafficking in the vascular system. The recognition of vascular homeostatic functions of vascular RTKs marks an important change of paradigm in the field of angiogenesis research as it relates angiogenesis-inducing molecules to vascular maintenance functions in the adult. This may also broaden the scope of vascular RTK-targeted therapies.
Electrochemical Reduction Products of Carbon Dioxide at Some Metallic Electrodes in Nonaqueous Electrolytes
Authors: Ito Kaname , Ikeda Shoichiro , Yamauchi Nobuhiro , Iida Takaya , Takagi Takehiko 
Published: July 2006

Abstract
Regarding the electrochemical reduction of carbon dioxide in nonaqueous electrolytes, it has been clarified that the main products are oxalic acid at a Pb electrode and carbon monoxide at Sn and In electrodes. In the case of a Zn electrode, substantial amounts of oxalic acid, glyoxylic acid and carbon monoxide have been produced.
cis-Oxypalladation Complexes Derived from (1R,5R)-2(10),3-Pinadiene and Their Utilization in Pd(II)-catalyzed Enantioselective Cyclization of 2-(trans-2-Butenyl)phenols
Authors: Hosokawa Takahiro , Imada Yasushi , Murahashi Shun-Ichi 
Published: July 2006

Abstract
(1R,5R)-2(10),3-Pinadiene, when treated with either Na2PdCl4 in MeOH or Pd(OAc)2 in AcOH and NaCl, gives di-μ-chloro-bis[(3,2,10-η-cis-4-methoxy or acetoxypinene)palladium(II)] (4a) or (4b), respectively. These complexes represent the firstly isolated cis-oxypalladation adduct. The ligand exchange of 4b with AgOAc affords di-μ-acetato-bis[(3,2,10-η-cis-4-acetoxypinene)palladium(II)] (5b) which serves as the catalyst for the asymmetric cyclization of 2-(trans-2-butenyl)phenols leading to 2-vinyl-2,3-dihydrobenzofurans (13). Although the enantioselectivities induced in this asymmetric cyclization are not high (1–29% ee), noteworthy is that the cis-complex 5b affords (R)-(−)-enantiomer of 13 while the parent di-μ-acetato-bis[(3,2,10-η-pinene)palladium(II)] give the (S)-isomer. As an application of the present asymmetric cyclization, attempts to synthesize (S)-(+)-tremetone have been made.
Total Syntheses of (±)-Aerothionin, (±)-Homoaerothionin, and (±)-Aerophobin-1
Authors: Nishiyama Shigeru , Yamamura Shosuke 
Published: July 2006

Abstract
(±)-Aerothionin, (±)-homoaerothionin, and (±)-aerophobin-1 have been successfully synthesized using phenolic oxidation of the methyl pyruvate oxime derivative with thallium(III) trifluoroacetate as a key step. The stereostructure of aerophobin-2 has been also established by comparison of the 1H NMR spectrum with those of related compounds.
Preparation and Some Properties of Cobalt(III) Complex with d- and/or l-Selenomethioninates
Authors: Umehara Hideki , Konno Takumi , Okamoto Ken-ichi , Hidaka Jinsai 
Published: July 2006

Abstract
A novel cobalt(III) complex with d- and/or l-selenomethioninates (d- and/or l-semet) functioning as terdentate-N,O,Se ligand was prepared and separated into the five geometrical isomers, trans(N), trans(O), trans(Se), cis,cis,cis, and trans,trans,trans. Of these isomers trans(N)- and trans(O)-[Co(d- or l-semet)2]+ and cis,cis,cis-[Co(d-semet)(l-semet)]+, which were obtained as the crystalline state, were optically resolved by the column chromatographic method. All the isomers were characterized by the electronic absorption, 1H NMR, and CD spectra. The trans(N), trans(O), and cis,cis,cis isomers in the crystalline state take the selective configurations with respect to the absolute configuration, R(Se) or S(Se), of the two coordinated selenium atoms. While, these isomers in an aqueous solution are a mixture of some configurations in the equilibrium state. For the inversion on the asymmetric selenium donor atom of the trans(N) and cis,cis,cis isomers, the rate constants and the ΔG\eweq values are investigated on the basis of the absorption and 1H NMR spectral changes. The trans(N) and cis,cis,cis isomers showed the characteristic CD spectral behavior in the d–d absorption band region depending on the inversion on the asymmetric selenium donor atoms.
Wheat Carboxypeptidase-Catalyzed Peptide Synthesis by Aminolysis of N-Acyl Amino Acid Ester. Indication of the Acyl-Enzyme Mechanism
Authors: Shima Hiroshi , Fukuda Mitsuhiro , Tanabe Kazuo , Ito Takanobu , Kunugi Shigeru 
Published: July 2006

Abstract
Dipeptide synthesis from N-[3-(2-furyl)acryloyl]-acylated (Fua-) amino acid ethyl ester and amino acid amide catalyzed by wheat bran carboxypeptidase (carboxypeptidase W) was studied. The optimum pH for peptide formation was at pH 8; more than 60% of the initial N-Fua-l-phenylalanine ethyl ester was converted to N-Fua-l-phenylalanylglycinamide under optimum conditions. The dependence of peptide formation on the concentration of amino acid amide showed an apparent saturation; this could be successfully explained by a reaction scheme which involved an acylated enzyme attacked by an enzyme-bound amine. The results for a reaction in the presence of two different amine components also supported this mechanism. Gly–NH2 had a better affinity to the acylated carboxypeptidase and the apparent dissociation constant (KN(app)) was about 50 mM. These results were compared with those for those reactions catalyzed by carboxypeptidases from yeast and malt.
Electrocrystallization of Phenothiazine
Authors: Yakushi Kyuya , Yoshitake Michiko , Kuroda Haruo 
Published: July 2006

Abstract
New cation radical salts of phenothiazine with (1:1), (3:2), and (2:1) compositions were prepared by the method of electrochemical oxidation. The electrical resistivities measured on the compaction of crystalline powder were 103–105 Ω cm at room temperature in the case of the complex salts. The powder absorption spectra in IR and Visible regions were also studied.
An Estimation of the Configurational Stability of Diaryl Selenoxides by Means of 77Se NMR Spectroscopy
Authors: Shimizu Toshio , Yoshida Masato , Kobayashi Michio 
Published: July 2006

Abstract
The activation energies for the racemization of the optically active diaryl selenoxides were estimated by the use of the 77Se NMR spectra of the diastereomeric diaryl selenoxides.
The Mechanism of Electron Transfer Reaction for Xanthene Dye-Sensitized Formation of Methyl Viologen Radical
Authors: Usui Yoshiharu , Misawa Hiroaki , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
Sensitized reduction of methyl viologen, MV2+, occurs efficiently through electron transfer from triplet xanthene dyes to MV2+ followed by electron transfer to the resulting semioxidized dyes from a reductant like triethanolamine. Unreactive ion pair complexes between these dyes and MV2+ are formed (formation constant: 1.2×103 M−1 for Eosine Y and MV2+ in 50% aqueous ethanol solution). The quantum yield for the reduced methyl viologen radical depends on the concentrations of MV2+ and the amine and on the ionic strength of solution. The efficiency of the electron transfer from triplet dyes to MV2+ is increased by addition of alcohol, and solvent effects on the reaction mechanism are discussed.
Preparation and Characterization of Cobalt(III) Complexes with l-Cysteinate and S-Methyl-l-Cysteinate. Crystal Structure of (l-Cysteinato)(diethylenetriamine)cobalt(III) Perchlorate
Authors: Okamoto Ken-ichi , Umehara Hideki , Nomoto Masayo , Einaga Hisahiko , Hidaka Jinsai 
Published: July 2006

Abstract
Of three possible isomers for the (l-cysteinato)(diethylenetriamine)cobalt(III) complex, [Co(l-cys)(dien)]+, two isomers are selectively prepared. Of the two isomers, the crystal structure of the dominantly formed isomer has been determined by the X-ray diffraction method. The greenish brown needle crystal was orthorhombic, space group P212121, a=16.589(4), b=20.510(9), c=12.479(4) Å, and Z=4. The structure has been refined to R=0.068 on 5913 observed reflections. There are three crystallographically independent complex cations in an asymmetric unit. All the complex cations have trans(NiS) configuration and the l-cysteinate coordinates facially to the cobalt atoms as terdentate-N,O,S ligand. The isomers of the (S-methyl-l-cysteinato)(diethylenetriamine)cobalt(III) complex were derived from [Co(l-cys)(dien)]+ by the reaction with dimethyl sulfate. The electronic absorption, CD, and 1H and 13C NMR spectral behaviors for these complexes are discussed in relation to their geometrical configurations.
Aryliminodimagnesium Reagents. XI. Two-Electron Oxidation of the Reagent Molecules in the Reaction with Some Oxidizing Agents and with Strongly Push-Pull Substituted α-Benzylideneacetophenones
Authors: Okubo Masao , Yoshida Shunsei , Egami Yoshiji , Matsuo K\={o}ji , Nagase Shigeru 
Published: July 2006

Abstract
The reactions of an aryliminodimagnesium reagent (ArN(MgBr)2) with four oxidizing agents ((i): I2, OsO4, C6H5IO2, I2O5) and four push-pull substituted α-benzylideneacetophenones(ii) were examined. In the reactions with (i), the maximum yield of sym-azobenzene was 50%. In the reactions with (ii), in addition to products formed via condensation and the typical radical processes, unexpected products formed via cleavages of C=C and Cβ–H bonds were observed. Summarizing these results, a pathway involving the formation of arylnitrene-like species via disproportionation of arylaminyl radicals (Ar\.{N}MgBr) has been proposed.