Hybridization of Bogoliubov Quasiparticles between Adjacent CuO_{2} Layers in the Triple-Layer Cuprate Bi_{2}Sr_{2}Ca_{2}Cu_{3}O_{10+δ} Studied by Angle-Resolved Photoemission Spectroscopy.

Hybridization of Bogoliubov quasiparticles (BQPs) between the CuO_{2} layers in the triple-layer cuprate high-temperature superconductor Bi_{2}Sr_{2}Cu_{2}Cu_{3}O_{10+δ} is studied by angle-resolved photoemission spectroscopy (ARPES). In the superconducting state, an anticrossing gap opens between the outer- and inner-BQP bands, which we attribute primarily to interlayer single-particle hopping with possible contributions from interlayer Cooper pairing. We find that the d-wave superconducting gap of both BQP bands smoothly develops with momentum without an abrupt jump in contrast to a previous ARPES study. Hybridization between the BQPs also gradually increases in going from the off nodal to the antinodal region, which is explained by the momentum dependence of the interlayer single-particle hopping. As possible mechanisms for the enhancement of the superconducting transition temperature, the hybridization between the BQPs as well as the combination of phonon modes of the triple CuO_{2} layers and spin fluctuations represented by a four-well model are discussed.

Socioecological differences in factors associated with inconsistent condom use with female sex workers and casual partners: an observational study of heterosexual men attending an anonymous HIV testing clinic in Singapore.

Sexual practices among heterosexual men may differ between female sex workers (FSWs) and casual partners. We surveyed 203 heterosexual men and investigated the attributes associated with inconsistent condom use among them. Lower educational attainment was positively associated with inconsistent condom use with FSWs (adjusted prevalence ratio (aPR) 2.63; P = 0.018) and casual partners (aPR 1.55; P = 0.022), whereas early age of sexual debut (aPR 3.00; P = 0.012) and alcohol use during sex (aPR 7.95; P < 0.001) were positively associated with inconsistent condom use with FSWs. Socioecological factors may explain such differences.

Enhanced superconducting gaps in the trilayer high-temperature Bi2Sr2Ca2Cu3O(10+δ) cuprate superconductor.

We report the first observation of the multilayer band splitting in the optimally doped trilayer cuprate Bi2Sr2Ca2Cu3O(10+δ) (Bi2223) by angle-resolved photoemission spectroscopy. The observed energy bands and Fermi surfaces are originated from the outer and inner CuO2 planes (OP and IP). The OP band is overdoped with a large d-wave gap around the node of Δ0∼43 meV while the IP is underdoped with an even large gap of Δ0∼60 meV. These energy gaps are much larger than those for the same doping level of the double-layer cuprates, which leads to the large Tc in Bi2223. We propose possible origins of the large superconducting gaps for the OP and IP: (1) minimal influence of out-of-plane disorder and a proximity effect and (2) interlayer tunneling of Cooper pairs between the OP and IP.

Efficacy of open patch-grafting under cardiopulmonary bypass for pulmonic stenosis in small dogs.

OBJECTIVE: To assess the efficacy of an open patch-graft technique under cardiopulmonary bypass (CPB) in small dogs. DESIGN AND METHODS: A retrospective analysis of 10 dogs with pulmonic stenosis. Records between 1992 and 2002 were reviewed. The effect of surgical correction was evaluated and perioperative parameters were compared between survivors and non-survivors. RESULTS: The postoperative pulmonary pressure gradient was reduced in all seven surviving patients. Mean +/- SE was 21.5 +/- 7.4 mmHg (range 3.0-54.2 mmHg) and 6/7 dogs were < 40 mmHg at 3 months postoperatively. Comparing the data between those patients that survived and those that did not, the preoperative pressure gradient (P = 0.04) and volume of the Glucose-Insulin-Kalium solution used (P = 0.001) were significantly higher in those that did not survive. CONCLUSION: Open patch-grafting can be performed in small-breed dogs and decreased the pulmonary pressure gradient in survivors at 3 months postoperatively. However, this technique is more invasive than balloon valvuloplasty and should be used cautiously in severely stenosed patients.

Composition of the microbiota in forestomach fluids and feces of Japanese Black calves with white scours.

The objective of this study was to characterize the composition of the forestomach and fecal microbiota in Japanese Black calves with white scours. Forestomach fluid, feces, and peripheral blood were collected from healthy calves ( = 5; age 10 ± 2 d) and scouring calves ( = 5; age 10 ± 1 d) on the day on which white scours occurred. The pH and concentrations of VFA, lactic acid, and ammonia nitrogen (NH-N) of the forestomach fluids were determined. Microbiota composition and gene copy numbers in the forestomach fluid and feces were analyzed by 454 pyrosequencing and quantitative real-time PCR (qPCR), respectively. The cytokine mRNA level in peripheral leukocytes was evaluated by qPCR. The pH of the forestomach fluid of the scouring calves tended to be higher than that of the healthy calves ( = 0.056). No significant difference was detected in the total VFA, lactic acid, or NH-N concentrations in the forestomach fluids of the 2 groups. Firmicutes, Bacteroidetes, and Proteobacteria were the predominant phyla in the forestomach fluid and feces. At the genus level, the relative abundance of in the forestomach fluid was significantly higher in the scouring calves ( < 0.05) and the relative abundance of in the feces was significantly higher than that in the forestomach in the healthy calves ( < 0.05). Furthermore, the bacterial diversity indices of feces were lower in the scouring calves. Quantitative PCR amplification using some of the primer pairs failed in the forestomach fluid and feces in both groups. These results suggested that fermentation in the forestomach may affect the occurrence of white scours, resulting in changes in the composition and diversity of the forestomach fluid and fecal microbiota in Japanese Black calves.

Real-time observation of a single DNA digestion by lambda exonuclease under a fluorescence microscope field.

A fluorescence microscopy technique has been developed to visualize the behavior of individual DNA and protein molecules. Real-time direct observation of a single DNA molecule can be used to investigate the dynamics of DNA-protein interactions, such as the DNA digestion reaction by lambda exonuclease. In conventional methods it is impossible to analyze the dynamics of an individual lambda exonuclease molecule on a DNA because they can only observe the average behavior of a number of exonuclease molecules. Observation of a single molecule, on the other hand, can reveal processivity and binding rate of an individual exonuclease molecule. To evaluate the dynamics of lambda exonuclease, a stained lambda DNA molecule with one biotinylated terminal was fixed on an avidin-coated coverslip and straightened using a d.c. electric field. Microscopic observation of digestion of a straightened DNA molecule by lambda exonuclease revealed that the DNA digestion rate was approximately 1000 bases/s and also demonstrated high processivity.

The hypocholesterolemic action of TA-7552 and its effects on cholesterol metabolism in the rat.

The hypocholesterolemic property of 1-(3,4-dimethoxyphenyl)-2,3- bis(methoxycarbonyl)-4-hydroxy-6,7,8-trimethoxynaphthalene (TA-7552) and its effects on cholesterol metabolism were investigated in the rat. TA-7552 incorporated into a hypercholesterolemic diet at a concentration of 0.2% and administered for 7 days reduced serum cholesterol by 72% and liver cholesterol by 90%, and its minimal effective dose was 0.01% in the diet. Its hypocholesterolemic effect was associated with an elevation of serum HDL-cholesterol. Inclusion of 0.1% TA-7552 in the normal laboratory chow accelerated fecal excretion of 14C derived from orally administered 4-[14C]cholesterol or carbonyl-[14C]taurocholate. The net amounts of fecal neutral sterols and bile acids were markedly increased by the same treatment. Hepatic bile acid production and hepatic and intestinal cholesterol biosynthesis as measured by cholesterol 7 alpha-hydroxylase activity and 1-[14C]acetate incorporation into tissue cholesterol, respectively, were both stimulated by the drug treatment. All these data indicate that this hypocholesterolemic agent inhibits intestinal absorption of both cholesterol and bile acids and compensatorily stimulates hepatic production of bile acids and cholesterol.

Synthesis of ethyl 2-(4-chlorophenyl)-5-(2-furyl)-4-oxazoleacetate, a hypolipidemic agent, and related compounds.

A series of 2-aryl and 2-alkyl derivatives of 5-furyl-4-oxazoleacetic acid and their homologues having alkyl groups at the alpha-position of the acids were synthesized and evaluated for their hypolipidemic activities in Sprague-Dawley rats. On the basis of the structure-activity relationships and subacute toxicities, ethyl 2-(4-chlorophenyl)-5-(2-furyl)-4-oxazoleacetate (35) was selected as a candidate compound for development. Compound 35 reduced serum cholesterol and triglyceride levels by 23% and 35%, respectively, at a dose of 0.05% in a diet in normal rats, and it was about 10 times more active in hereditary hyperlipidemic rats (THLR/1) than in normal rats. Compound 35 inhibited platelet aggregation in vitro and also normalized hyperaggregability of hyperlipidemic plasma platelet ex vivo.

Studies of hypolipidemic agents. 1. Synthesis and hypolipidemic activities of alkoxycinnamic acid derivatives.

More than 110 derivatives of alkoxycinnamic acids were synthesized and their hypolipidemic activities were evaluated in a screening system with rats. Cinnamic acids, alpha-methylcinnamic acids, and their various esters with a higher p-alkoxy substituent were found to possess hypolipidemic activities higher than or comparable to that of clofibrate. The proper length (C12--C16) and the para position of the alkoxy substituent seem to be essential for activity. Chloroethyl and methacryloxyethyl esters and monoglycerides of some of the active p-alkoxycinnamic acids were more active than the corresponding free acids.

Synthesis and hypolipidemic activities of 5-thienyl-4-oxazoleacetic acid derivatives.

A series of 2,5-disubstituted 4-oxazoleacetic acid derivatives was synthesized and evaluated for hypolipidemic activity. Among them, those with a thienyl group at C-5 of the oxazole ring exerted highly potent hypolipidemic effects in rats. 2-(4-Fluorophenyl)-5-(3-thienyl)-4-oxazoleacetic acid (88) was the most potent derivative: it was about 2 times as active in normal SD male rats and about 4 times as active in hereditary hyperlipidemic rats (THLR/1) as clofibrate with an improved antiarteriosclerosis index (HDL-Cho/Total-Cho). In addition, it showed inhibition of platelet aggregation ex vivo.

Strain variation in renal carcinogenesis by N-ethyl-N-hydroxyethylnitrosamine in F1 (Wistar-Fischer) rats.

The present study was conducted to compare the incidences of renal tumors in Wistar (W), Fischer (F) and F1 rats (WF: female Wistar rats x male Fischer rats; FW: female Fischer rats x male Wistar rats) induced by N-ethyl-N-hydroxyethylnitrosamine (EHEN). Levels of 8-OHdG in renal DNA were also investigated in Wistar and Fischer rats. After 2000 ppm of EHEN was administered orally for 2 weeks, the animals were fed basal diet until week 32. Wistar males and females demonstrated significantly higher sensitivity regarding induction of renal lesions, while both WF and FW rats had similar incidences, generally intermediate between those for the two parent strains. The formation of 8-OHdG was maximal 60-180 min after an intraperitoneal dose of 750 mg/kg to Wistar and Fischer rats, which correlates with the increase tending to the incidence of renal tumors in male and female Wistar and Fischer rats. The results suggest that EHEN induction of renal tumors is related to oxygen radical damage and that the genes in the Wistar strain responsible for the sensitivity are not inherited in a sex-dependent fashion, despite the male being more susceptible.

Reconstitution of compact polynucleosomes and comparison of the functions of histones H1 and H5.

Polynucleosomes with a definite length (about 4,500 base pairs) were prepared from chicken erythrocyte nuclei without depleting magnesium ions from the medium. The polynucleosomes in the presence of Mg2+ ions as well as monovalent salts were more compact than those with monovalent salts alone. We minimized the occurrence of nicks in the DNA of nucleosome fiber during the preparation. When histones H1 and H5 were completely removed from polynucleosomes, linker histone-depleted polynucleosomes sedimented slower than the original ones. When isolated histone H1 or H5 was reassembled with linker histone-depleted polynucleosomes, no significant difference was observed among the reconstituted polynucleosomes with histone H1, the reconstituted polynucleosomes with histone H5, and the original polynucleosomes. We concluded that histones H1 and H5 are similar in their effects on higher order structure of polynucleosomes, as far as can be judged from such characteristics as sedimentation velocity, linker histone content, and the patterns of nuclease digestion.

Rapid induction of atherosclerosis in rabbits.

Japanese white rabbits fed a restricted amount (100 g/head/day) of an atherogenic diet (AD) containing 0.2% cholesterol and 6% peanut oil showed mild and persistent hypercholesterolemia (338 +/- 79 mg/dl). They developed atherosclerotic lesions 4 weeks after deendothelialization of aorta carried out at the 4th week of AD-feeding. This rabbit model of atherosclerosis has such advantages as being able to be produced in a short period and having similar biochemical and pathological characteristics with those in human atherosclerosis.

G-protein mediating the slow depolarization induced by FMRFamide in the ganglion cells of Aplysia.

Application of FMRFamide (Phe-Met-Arg-Phe-NH2) induced a slow depolarization in neurons of the Aplysia abdominal ganglion. In voltage-clamped cells, FMRFamide induced a slow inward current that increased when the membrane was depolarized beyond -85 mV, showing a negative slope conductance. However, this inward current never reversed to outward current when hyperpolarized beyond the equilibrium potential for K+. The FMRFamide-induced response was markedly augmented in Ca(2+)-free media, but depressed in Na(+)-free media. It was unaffected by a change in external potassium. Intracellular injection of guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) significantly depressed the FMRFamide response in a dose-dependent way. Injection of cholera toxin (CTX) which did not cause any current response, selectively and irreversibly blocked the FMRFamide response. Neither 3'-deoxyadenosine, an inhibitor of adenylate cyclase, nor H-8, an inhibitor of cyclic adenosine 3',5'-monophosphate (cyclic AMP)-dependent kinase, depressed the FMRFamide response. 3-Isobutyl-1-methylxanthine (IBMX) did not augment the FMRFamide response appreciably. The FMRFamide response was not occluded at all by a relatively large injection of 8-bromo-cyclic AMP. It was concluded that the FMRFamide response is produced by the opening of the voltage-dependent Na(+)-channels via activation of a certain CTX-sensitive G-protein which is different from conventional "Gs" that activates adenylate cyclase.

Establishment of a model of penicillin-resistant Streptococcus pneumoniae pneumonia in healthy CBA/J mice.

Examination of strain differences in the susceptibility of mice to experimental respiratory tract infection with penicillin-resistant Streptococcus pneumoniae TUM19 revealed that a fatal infection model could be induced in immunocompetent CBA/J mice, but not in C3H/HeN, C57BL/6 or ICR mice. After intranasal instillation of c. 10(6) cfu of S. pneumoniae, the bacterial counts in the lungs of CBA/J mice increased from 10(5) to 10(7) cfu after 3-5 days, and gradually increased thereafter. The challenge organisms localised mainly in the lungs until 14 days after infection. Mice began to die c. 7 days after infection, and by 3 weeks most of the mice had died. Histopathologically, infiltration of neutrophils and lymphocytes around bronchi was observed from 1 day after infection, and fibrin deposition was seen in alveolar and bronchial spaces from 5 days. This model may be useful for investigating therapy of respiratory tract infection caused by penicillin-resistant S. pneumoniae because its pathological features resemble those observed in the human disease.

The transmitter-induced change in slope conductance of a receptor membrane as a function of the resting potential and equilibrium potential of the ion involved.

Change in slope conductance has been widely used to evaluate the ion-channel activation by receptor agonists of various postsynaptic membranes. However, the agonist-induced change in slope conductance (delta G) depends not only on the change in membrane ionic permeabilities (delta P) but also on the changes in resting potential (E) and equilibrium potential (EA) of the ion involved (A). A constant field theory was applied to describe delta GA as a function of delta PA, E and EA, assuming that delta PA is not affected by the change in E or EA. This equation predicts that delta GNa will decrease if the membrane is depolarized or when ENa becomes more positive. Similarly, delta GK is expected to increase if the membrane is depolarized or when EK becomes more negative. Further, the equation describes that delta GCl will increase if the membrane is depolarized or when ECl becomes less negative. These changes in GNa, GK and GCl are well consistent with many data previously obtained from various types of receptor membranes. We conclude that the values of slope conductance measured at different E or EA must be carefully corrected in order to estimate the real voltage dependence of delta P or the ion-channel activation by receptor agonists.

Amperometric biosensor with a composite membrane of sol-gel derived enzyme film and electrochemically generated poly(1,2-diaminobenzene) film.

A sol-gel silicate-based biosensor for glucose was made by utilizing a composite membrane of sol-gel enzyme film and electrochemically generated poly(1,2-diaminobenzene) film to improve the selectivity of the sol-gel enzyme sensors. The stability of the sensor was improved by exposing the enzyme layer to glutaraldehyde vapor. The glucose sensor responded rapidly (ca. 15 s) to glucose at 0.6 V (versus Ag/AgCl), without any interferences from electroactive species such as L-ascorbate and urate below 0.2 mM. Reliable results were obtained in the assays of glucose in controlled human sera, with both the steady-state and flow-injection measurements. Subsequently, the same sol-gel procedure was applied to the preparation of the sensors for galactose and cholesterol. The galactose and cholesterol sensors responded rapidly to galactose and cholesterol, respectively, although the sensitivity of these sensors was inferior to that of glucose sensor.

DMSO effects on synaptic facilitation and calcium dependence in bullfrog sympathetic ganglion.

Synaptic transmission in the bullfrog sympathetic ganglion was studied by means of extra- and intracellular recordings. DMSO (3-10%) caused a single orthodromic stimulus to generate a brief burst of repetitive postganglionic discharges. DMSO also partially reversed a preexisting transmission failure in low Ca2+ medium. Ganglia were exposed to gradual reductions in extracellular Ca2+, in the absence and in the presence of DMSO. The recorded amplitude of the postganglionic compound action potential (CAP) was plotted as a function of Ca2+ concentration. In the absence of DMSO transmission failed progressively as Ca2+ was reduced from 1.8 to 0.47 mM but DMSO (3% and 10%) shifted the curve of transmission failure to the left (lower Ca2+ concentration). DMSO inhibits ganglion cholinesterase activity, but this is not the mechanism of its facilitatory effect on Ca2+ entry, since physostigmine did not shift the curve of transmission failure in low Ca2+ to the left. The data suggest that DMSO maintained transmitter release in low Ca2+ by a direct, nonspecific enhancement of Ca2+ influx into the presynaptic nerve terminal.

Comparison of a 1.0 molar and a 0.5 molar formulation of gadobutrol in dynamic MR imaging of the liver in rats with hepatocellular carcinoma.

The efficacy of a 1.0 molar formulation of gadobutrol was compared with that of a 0.5 molar formulation in dynamic magnetic resonance (MR) imaging of the liver in rats with hepatocellular carcinoma (HCC). Seven nodules histologically identified as moderately differentiated HCC underwent dynamic study. In the normal parenchyma surrounding these tumors, the 0.5 molar and 1.0 molar formulations yielded similar enhancement patterns, with maximum enhancement value of approximately 35% at 20 to 40 s after injection. In the tumors, the 0.5 molar formulation induced approximately 65% enhancement, whereas the 1.0 molar formulation, used at the same dose as the 0.5 molar formulation, induced significantly higher enhancement until 10 min after injection with maximum enhancement of approximately 90%. These findings indicate that the 1.0 molar formulation could be more efficacious than the 0.5 molar formulation in dynamic MR studies of moderately differentiated HCC even when injected at the same dose.