Cluster-Based Haldane State in an Edge-Shared Tetrahedral Spin-Cluster Chain: Fedotovite K_{2}Cu_{3}O(SO_{4})_{3}.

Fedotovite K_{2}Cu_{3}O(SO_{4})_{3} is a candidate of new quantum spin systems, in which the edge-shared tetrahedral (EST) spin clusters consisting of Cu^{2+} are connected by weak intercluster couplings forming a one-dimensional array. Comprehensive experimental studies by magnetic susceptibility, magnetization, heat capacity, and inelastic neutron scattering measurements reveal the presence of an effective S=1 Haldane state below T≅4 K. Rigorous theoretical studies provide an insight into the magnetic state of K_{2}Cu_{3}O(SO_{4})_{3}: an EST cluster makes a triplet in the ground state and a one-dimensional chain of the EST induces a cluster-based Haldane state. We predict that the cluster-based Haldane state emerges whenever the number of tetrahedra in the EST is even.

Coulomb Correlations Intertwined with Spin and Orbital Excitations in LaCoO_{3}.

We carried out temperature-dependent (20-550 K) measurements of resonant inelastic x-ray scattering on LaCoO_{3} to investigate the evolution of its electronic structure across the spin-state crossover. In combination with charge-transfer multiplet calculations, we accurately quantified the renomalized crystal-field excitation energies and spin-state populations. We show that the screening of the effective on-site Coulomb interaction of 3d electrons is orbital selective and coupled to the spin-state crossover in LaCoO_{3}. The results establish that the gradual spin-state crossover is associated with a relative change of Coulomb energy versus bandwidth, leading to a Mott-type insulator-to-metal transition.

Spin-orbit fluctuations in frustrated heavy-fermion metal LiV(2)O(4).

Spin fluctuations were studied over a wide momentum (ℏQ) and energy (E) space in the frustrated d-electron heavy-fermion metal LiV_{2}O_{4} by time-of-flight inelastic neutron scattering. We observed the overall Q-E evolutions near the characteristic Q=0.6 Å^{-1} peak and found another weak broad magnetic peak around 2.4 Å^{-1}. The data are described by a simple response function, a partially delocalized magnetic form factor, and antiferromagnetic short-range spatial correlations, indicating that heavy-fermion formation is attributable to spin-orbit fluctuations with orbital hybridization.

Emergence of highly degenerate excited states in the frustrated magnet MgCr2O4.

High degeneracy in ground states leads to the generation of exotic zero-energy modes, a representative example of which is the formation of molecular spin-liquid-like fluctuations in a frustrated magnet. Here we present single-crystal inelastic neutron scattering results for the frustrated magnet MgCr(2)O(4), which show that a common set of finite-energy molecular spin excitation modes is sustained in both the liquid-like phase above magnetic ordering temperature T(N) and an ordered phase with an extremely complex magnetic structure below T(N). Based on this finding, we propose the concept of high degeneracy in excited states, which promotes local resonant elementary excitations. This concept is expected to have ramifications on our understanding of excitations in many complex systems, including not only spin but also atomic liquids, complex order systems, and amorphous systems.

A new mathematical approach to finding global solutions of the magnetic structure determination problem.

Determination of magnetic structure is an important analytical procedure utilized in various fields ranging from fundamental condensed-matter physics and chemistry to advanced manufacturing. It is typically performed using a neutron diffraction technique; however, finding global solutions of the magnetic structure optimization problem represents a significant challenge. Generally, it is not possible to mathematically prove that the obtained magnetic structure is a truly global solution and that no solution exists when no acceptable structure is found. In this study, the global optimization technique called semidefinite relaxation of quadratic optimization, which has attracted much interest in the field of applied mathematics, is proposed to use as a new analytical method for the determination of magnetic structure, followed by the application of polarized neutron diffraction data. This mathematical approach allows avoiding spurious local solutions, decreasing the amount of time required to find a tentative solution and finding multiple solutions when they exist.

Hydrogen release reactions of Al-based complex hydrides enhanced by vibrational dynamics and valences of metal cations.

Hydrogen release from Al-based complex hydrides composed of metal cation(s) and [AlH4]- was investigated using inelastic neutron scattering viewed from vibrational dynamics. The hydrogen release followed the softening of translational and [AlH4]- librational modes, which was enhanced by vibrational dynamics and the valence(s) of the metal cation(s).

Differential metabolism of human VLDL according to content of ApoE and ApoC-III.

We studied the metabolism of very low density lipoprotein (VLDL) and intermediate density lipoprotein (IDL) particles that did or did not have apolipoprotein E (apoE) in 12 normolipidemic women by endogenously labeling plasma apolipoprotein B. The plasma was separated into bound (E+) and unbound (E-) fractions by use of a monoclonal antibody (1D7), and the fractions were ultracentrifuged to yield E+ and E- subfractions of light and dense VLDL and IDL. VLDL E+ and IDL E+ were produced mainly by the liver. VLDL E+ and IDL E+ had lower fractional catabolic rates and much higher apolipoprotein C-III (apoC-III) content than did the corresponding E- particles. Most light VLDL apoE+ underwent lipolysis to dense VLDL E+ with reduced apoC-III content, which was removed from the circulation without conversion to IDL. In contrast, most light VLDL apoE-, poor in apoC-III, was removed from the circulation, and a smaller proportion underwent lipolysis to dense VLDL E-. Most dense VLDL E- underwent lipolysis to IDL E-. The rate constant for lipolysis of dense VLDL to IDL was greater for E- than for E+, and the rate constant for clearance from plasma was greater for dense VLDL E+ than for E-. In conclusion, metabolism of human VLDL particles is influenced by their content of apoE, further modulated by the coexistence of apoC-III.

Effects of alcohol on lipoprotein lipase, hepatic lipase, cholesteryl ester transfer protein, and lecithin:cholesterol acyltransferase in high-density lipoprotein cholesterol elevation.

The mechanism whereby alcohol increases high-density lipoprotein cholesterol (HDL-C) levels is unclear. Lipoprotein lipase (LPL), hepatic lipase (HL), cholesteryl ester transfer protein (CETP) and lecithin:cholesterol acyltransferase (LCAT) act on lipoprotein metabolism. The purpose of the present study is to determine which one or what combination of these factors is responsible for the rise in HDL-C levels following alcohol ingestion. After 3 weeks of abstinence, 12 men consumed 0.5 g/kg bw of alcohol per day for 4 weeks; 13 abstaining men served as controls. Mean plasma total cholesterol (TC) levels were unchanged in either group throughout the study. Among the alcohol consumers, plasma triglycerides (TG), HDL-C, apolipoprotein (apo) A-I and A-II levels increased significantly after 3 weeks of alcohol loading but were unchanged in the control group. High-density lipoprotein3 cholesterol (HDL3-C) levels increased significantly in the alcohol consumers after 4 weeks of alcohol loading whereas high-density lipoprotein2 cholesterol (HDL2-C) levels were unaffected. In the controls, neither HDL2-C nor HDL3-C changed significantly. Post-heparin plasma (PHP) LPL activity and mass increased significantly (P < 0.01) after the alcohol ingestion (controls remained unchanged) without changing LPL specific activity. HL, CETP and LCAT activities were unaffected in both groups. We conclude that of the factors considered, LPL contributed the most to the alcohol-induced rise in HDL-C.

Stereoscopic observation of enzyme distribution in lowicryl K4M-embedded specimens by conventional electron microscopy.

The present investigation was undertaken to explore the value of the Lowicryl K4M embedding technique for enzyme histochemical examination of semi-thin sections. The low-temperature embedding procedure with Lowicryl K4M was found to provide favorable conditions for preservation of enzyme activity in tissue samples. We tested the histological effects of various fixatives; the best results were obtained using 4% paraformaldehyde when testing for AcPase, AlPase, TPPase, and Mg-ATPase in the dorsal root ganglion. The three-dimensional cellular fine structure could be clearly seen in stereo pair pictures under stereoscopy.

Inhibitory effect of tea flavonoids on the ability of cells to oxidize low density lipoprotein.

Dietary flavonoid intake has been reported to be inversely related to mortality from coronary heart disease, and the anti-atherosclerotic effect of flavonoids is considered to be due probably to their antioxidant properties. Oxidation of low density lipoprotein (LDL) has been reported to be induced by the constituent cells of the arterial wall. Accordingly, we examined the effect of pretreatment with tea flavonoids, such as theaflavin digallate, on the ability of cells to oxidize LDL. Theaflavin digallate pretreatment of macrophages or endothelial cells reduced cell-mediated LDL oxidation in a concentration- (0-400 microM) and time- (0-4 hr) dependent manner. This inhibitory effect of flavonoids on cell-mediated LDL oxidation was in the order of theaflavin digallate > theaflavin > or = epigallocatechin gallate > epigallocatechin > gallic acid. Further, we investigated the mechanisms by which flavonoids inhibited cell-mediated LDL oxidation using macrophages and theaflavin digallate. Theaflavin digallate pretreatment decreased superoxide production of macrophages and chelated iron ions significantly. These results suggest that tea flavonoids attenuate the ability of the cell to oxidize LDL, probably by reducing superoxide production in cells and chelating iron ions.

Effect of low-dose simvastatin on cholesterol levels, oxidative susceptibility, and antioxidant levels of low-density lipoproteins in patients with hypercholesterolemia: a pilot study.

In this pilot study, 12 patients (6 men, 6 postmenopausal women) with hypercholesterolemia were treated with low-dose (5 mg/d) simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, for 4 weeks. Low-density lipoprotein (LDL) samples were isolated at the beginning (week 0) and at the end (week 4) of the treatment regimen. Simvastatin caused significant decreases of total cholesterol (-18.1%), LDL cholesterol (-27.6%), and apolipoprotein B (-21.8%), and significantly reduced total cholesterol, free cholesterol, cholesterol esters, phospholipids, and protein in LDL without significantly changing the component ratios and fatty acid levels of LDL. However, simvastatin therapy had no major effects on either antioxidant levels in LDL or the oxidative susceptibility of LDL. We conclude that low-dose simvastatin significantly reduces LDL cholesterol levels without increasing the oxidative susceptibility of LDL or decreasing the antioxidant levels of LDL, and thus may reduce the risk of coronary artery disease.

Holmium laser resection of the prostate.

A total of 35 patients with benign prostatic hyperplasia (BPH) were treated with the Ho: YAG laser using a new technique termed holmium laser resection of the prostate or HoLRP. The laser energy was applied directly to prostatic tissue exclusively through the use of a standard 550 micron end-firing fiber. A high-powered holmium laser was used and was set at 2.4 J per pulse at 25 pulses per second for an average power of 60 W. The mean preoperative AUA Symptom Score was 24. Postoperatively, the score dropped to 10.9, 8.2, 5.2, and 4.6 at 1 week, 1 month, 3 months, and 6 months, respectively. The peak urine flow rate improved from 6.3 mL/sec preoperatively to 15.1, 15.3 and 16 mL/sec at 1 week, 1 month, 3 months, and 6 months. A foley catheter was removed within 24 hours of completion of the operation in 31 patients (89%), and voiding was improved. The HoLRP technique was bloodless, and the short-term results were satisfactory. Most importantly, the defect produced by HoLRP is identical to that of a conventional transurethral resection. These initial results demonstrate that HoLRP is a useful surgical alternative in the treatment of patients with obstructive BPH.

Anti-Hu antibody in a patient with Lambert-Eaton myasthenic syndrome and early detection of small cell lung cancer.

We report a patient with Lambert-Eaton myasthenic syndrome (LEMS) and anti-Hu antibody, which was an important clue in detecting small cell lung cancer (SCLC) at the early stage. This patient had no symptoms of anti-Hu associated paraneoplastic neurological syndrome. In LEMS patients in whom conventional tests fail to detect malignancy, anti-Hu antibody should be evaluated to diagnose SCLC at the early stage.

Effects of soy protein isolate (SPI) and casein on the postprandial lipemia in normolipidemic men.

To elucidate the effects of soybean protein and casein on postprandial lipemia, oral fat load tests were performed before and 3 weeks after the administration of soy protein isolate (SPI) and casein supplement to normolipidemic men. Eleven normolipidemic male subjects on otherwise identical controlled diets were assigned to either a 20 g/d soy protein isolate (SPI) dietary supplement or a casein dietary supplement for three weeks in a crossover design. Fat load tests with 40 g/m2 of bovine milk fat were carried out before and after 3 weeks on the experimental dietary supplements. Fasting plasma concentrations of lipids and apolipoproteins were not significantly different from baseline levels before or after the administration of SPI or casein supplemented diets. Neither SPI nor casein supplement affected the fasting plasma concentrations of lipids and apolipoproteins. The areas under the incremental curve (AUIC) of triglyceride (TG) and remnant-like particles triglyceride (RLP-TG) after both experimental diets were not significantly different from those before the experimental diets. However, the AUIC of remnant-like particles cholesterol (RLP-C) showed a tendency (p = 0.07) to decrease after administration of the diet supplemented with SPI than before the diet. The AUIC of RLP-C was significantly (p < 0.05) lower after the diet supplemented with SPI than after administration of the diet supplemented with casein. These results suggest that 3 weeks of 20 g/d SPI dietary supplement favorably affects the postprandial remnant lipoprotein response as compared to the casein dietary supplement.

Structure-dependent induction of CYP2B1/2 by 3-methylsulfonyl metabolites of polychlorinated biphenyl congeners in rats.

The effects of eleven 3-methylsulfonyl (3-MeSO(2))-metabolites of polychlorinated biphenyl (PCB) congeners (which were reported to remain in Swedish mother's milk and Japanese Yusho patient's tissues) and their two structurally similar 3-MeSO(2)-PCBs on the hepatic drug-metabolizing enzyme activities were compared with those of phenobarbital (PB) and 3-methylcholanthrene (3-MC).The induction profile of the drug-metabolizing enzymes, CYP2B1 and CYP2B2 in the hepatic microsomes of rats treated with nine 3-MeSO(2) derivatives, namely 3-MeSO(2)-2,4',5-trichlorobiphenyl, 3-MeSO(2)-2,2',4',5-tetrachlorobiphenyl (3-MeSO(2)-2,2',4',5-tetraCB), 3-MeSO(2)-2,2',5,5'-tetraCB, 3-MeSO(2)-2,3',4',5-tetraCB, 3-MeSO(2)-2,2',3',4',5-pentachlorobiphenyl (3-MeSO(2)-2,2',3',4',5-pentaCB), 3-MeSO(2)-2,2',4',5,5'-pentaCB, 3-MeSO(2)-2,2',3',4',5,5'-hexachlorobiphenyl (3-MeSO(2)-2,2',3',4',5,5'-hexaCB), 3-MeSO(2)-2,2',3',4',5,6-hexaCB and 3-MeSO(2)-2,2',4',5,5',6-hexaCB, was similar to that of rats treated with PB, but was different from that of rats treated with 3-MC. These findings indicate that 3-MeSO(2) metabolites derived from nine PCBs are PB-type inducers of microsomal drug-metabolizing enzymes. The relative inducing potencies of 3-MeSO(2) derivatives on the hepatic drug-metabolizing enzyme activities differed with the extent of chlorination and the positions of chlorine substituent on the phenyl rings. The results of present study show that the structure-CYP2B1/2 induction relationship exists for the 3-MeSO(2) derivatives studied. The inducing abilities of 3-MeSO(2)-2,2',4',5-tetraCB and 3-MeSO(2)-2,2',4',5,5'-pentaCB (2 µmol/kg) on the content of cytochrome P450 were higher than those of 2,3',4,4',5-pentaCB (mono-ortho-substituted PCB) (80 µmol/kg), 3,3',4,4'-tetraCB (coplanar PCB) (80 µmol/kg) and 3,3',4,4',5-pentaCB (coplanar PCB) (0.5 µmol/kg). The inducing effects of the administration of 3-MeSO(2)-2,2',4',5-tetraCB and 3-MeSO(2)-2,2',4',5,5'-pentaCB at 2 µmol/kg on the contents of total cytochrome P450, CYP2B1 and CYP2B2 corresponded to those of PB at 431 µmol/kg twice at a 24 h interval. It is noticeable that 3-MeSO(2)-2,2',4',5-tetraCB and 3-MeSO(2)-2,2',4',5,5'-pentaCB have highly potent PB-type inducing activity on drug-metabolizing enzyme systems.

The role of 3-methylsulfonyl-2,2',4',5,5'-pentachlorobiphenyl, a metabolite of 2,2',4,5,5'-pentachlorobiphenyl, in the induction of hepatic microsomal drug-metabolizing enzymes by 2,2',4,5,5'-pentachlorobiphenyl in rats.

After the administration of 2,2',4,5,5'-pentachlorobiphenyl (2,2',4,5,5'-pentaCB) to intact rats, the concentration of 2,2',4,5,5'-pentaCB in liver gradually decreased, whereas 3-methylsulfonyl (3-MeSO(2))-2,2',4',5,5'-pentaCB appeared in liver and remained detectable in liver for 6 weeks. A single injection of 2,2',4,5,5'-pentaCB (342 µmol/kg) or 3-MeSO(2)-2,2',4',5,5'-pentaCB (0.5 µmol/kg) caused a significant increase both in the contents of cytochromes P450 and b(5) and in the activities of aminopyrine N-demethylase and benzo[a]pyrene hydroxylase, and the increased enzyme contents and activities continued for 6 weeks after the administration. The extent of both the hepatic accumulation of 3-MeSO(2)-2,2',4',5,5'-pentaCB and the induction of the enzymes for 6 weeks after the administration of 2,2',4,5,5'-pentaCB was similar to that after the administration of 3-MeSO(2)-2,2',4',5,5'-pentaCB. 3-MeSO(2)-2,2',4',5,5'-pentaCB was considered to play a principal role in the induction of microsomal drug-metabolizing enzymes by 2,2',4,5,5'-pentaCB. When 2,2',4,5,5'-pentaCB was injected i.p. into bile duct-cannulated rats, 3- and 4-MeSO(2)-2,2',4',5,5'-pentaCBs were not detected in liver. In antibiotic-treated rats dosed with 2,2',4,5,5'-pentaCB, the concentrations of 3- and 4-MeSO(2)-2,2',4',5,5'-pentaCBs in liver were markedly reduced. These findings suggest that the process in which 3- and 4-MeSO(2) metabolites of 2,2',4,5,5'-pentaCB are formed involves the biliary secretion of some precursors which will be subjected to metabolism by intestinal microflora. The increasing effects of 2,2',4,5,5'-pentaCB both on the content of cytochrome P450 and on the activity of aminopyrine metabolizing enzyme in hepatic microsomes were not observed in the bile duct-cannulated rats, in which the phenobarbital treatment enabled the drug-metabolizing enzymes to be induced. In antibiotic-treated rats, the increases both in the cytochrome P450 content and in the aminopyrine N-demethylase activity after the administration of 2,2',4,5,5'-pentaCB were smaller than those observed in the intact rats. These findings provide the evidence that the induction of some drug-metabolizing enzymes by 2,2',4,5,5'-pentaCB is due not to the action of 2,2',4,5,5'-pentaCB itself but to its 3-methylsulfonyl metabolite, 3-MeSO(2)-2,2',4',5,5'-pentaCB.

[A case of X-linked bulbospinal muscular atrophy with bilateral abductor vocal cord paralysis].

We report a 54-year-old man with X-linked bulbospinal muscular atrophy (BSMA) with bilateral abductor vocal cord paralysis. He noticed distal weakness in the lower limbs at age 20. In the following 18 years the weakness and atrophy of his leg muscles increased gradually. He has complained of stridors during respiratory tract infection and snored heavily during sleep since his age of 50. He was admitted to our hospital for the progressive stridors during meals. His two brothers were said to have similar complaints. Physical examination showed gynecomastia, hypertension and inspiratory stridor. Neurologic examination revealed distal muscular atrophy in his four extremities, especially more severe in bilateral lower limbs. Deep tendon reflexes were absent in all extremities. His tongue was slightly atrophic with fasciculation. Neurological diagnosis was made by family history, neurological findings, electromyography and a CAG repeat expansion in the androgen receptor gene. Lungs and diaphragm were normal on the chest radiograph. Cranial MRI including brain stem was also normal. Direct laryngoscopy showed a complete paralysis of both vocal cords in paramedian position. Tracheostomy was done right away; his respiratory distress showed prompt improvement after the tracheostomy. No previous report of bilateral vocal cord paralysis in BSMA has been found. Life expectancy in BSMA patients with vocal cord paralysis may be shortened because of respiratory distress or asphyxia. Of clinical importance is a careful assessment of vocal cord function in BSMA patients.

[A case of AIDS-associated primary CNS lymphoma difficult to differentiate from toxoplasmic encephalitis by clinical symptoms, neuroimages, and therapeutic responses].

We reported a 24-year-old Thai woman who developed primary CNS lymphoma (PCNSL) associated with acquired immunodeficency syndrome. It was difficult to distinguish PCNSL from toxoplamic encephalitis in this case by clinical symptoms, findings of CT and MRI, and therapeutic responses for toxoplasmosis. It is important to make a definite diagnosis of PCNSL by brain biopsy to treat appropriately, because this disorder could be fatal if it is not treated by corticosteroid, radiation, or other proper methods.

[Optimal fixation for the detection of anti-neuronal antibody by immunohistochemistry in the paraneoplastic syndrome].

Paraneoplastic syndrome(PS) associated anti-neuronal autoantibodies are characterized by their antigen molecular weight determined by Western blot and immunostaining pattern recognized through immunohistochemistry. We investigated immunohistochemical fixatives for their sensitivity in the detection of anti-neuronal nuclear antibody(Hu). Serum used for this study was taken from a patient with anti-Hu antibody seropositivity, which was ascertained by recombinant Hu protein. Western blot analysis produced 37kDa band. We examined six fixative conditions: immersion fixed with acetone, Bouin's solution, Sakura rapid fixative("Ufix'), and perfusion fixed with 2%, 4%, 8% paraformaldehyde (PFA) on the basis of each immunoreactivity in a rat cerebellum, brain stem and liver. The optimal fixation for detecting anti-Hu antibody was perfusion fixed with 2% PFA, that reacted conspicuously with nucleus but not nucleolus of neurons. The perfusion method proved superior to immersion in immunostaining intensity. With immersion fixation, specific immunostaining pattern lessened and differentiation from cytoplasm decreased. With various concentrations of PFA, immuno-reactivity with nucleus at 2% PFA was similar to 4%, although serum optimal dilution at 2% was slightly greater than 4%. The variety of staining patterns of anti-Hu antibody is closely related to the vulnerability of neuronal antigens to the fixatives. The detection of anti-neuronal antibodies is important for early diagnosis and treatment of occult tumors. The immunostaining method is a useful and sensitive way to research these antibodies. Therefore, it is essential to consider the selection of fixation and the preservation of the antigenicity in evaluating immunohistochemical hallmarks.