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.

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.

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).

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.

Molecular spin resonance in the geometrically frustrated magnet MgCr2O4 by inelastic neutron scattering

We measured two magnetic modes with finite and discrete energies in an antiferromagnetic ordered phase of a geometrically frustrated magnet MgCr2O4 by single-crystal inelastic neutron scattering, and clarified the spatial spin correlations of the two levels: one is an antiferromagnetic hexamer and the other is an antiferromagnetic heptamer. Since these correlation types are emblematic of quasielastic scattering with geometric frustration, our results indicate instantaneous suppression of lattice distortion in an ordered phase by spin-lattice coupling, probably also supported by orbital and charge. The common features in the two levels, intermolecular independence and discreteness of energy, suggest that the spin molecules are interpreted as quasiparticles (elementary excitations with energy quantum) of highly frustrated spins, in analogy with the Fermi liquid approximation.

Primary carcinoid of the testis associated with carcinoid syndrome

Testicular carcinoid is a rare disease accounting for less than 1% of all testicular neoplasms. It rarely manifests symptoms of carcinoid syndrome. Recent reports have noted that only 1.1-3.1% of testicular carcinoid tumors are complicated by carcinoid syndrome. In general, large tumor size and the presence of carcinoid syndrome are features associated with a malignant course. In the present case, pathological findings revealed pure carcinoid of the testis without metastasis. Moreover, watery diarrhea due to carcinoid syndrome disappeared and the serum serotonin level normalized following orchiectomy. The patient was followed up for 12 months with whole body computed tomography scan and assessment of serotonin levels. To date, there is no evidence of tumor recurrence. These findings suggest that monitoring serum serotonin levels may be useful as a marker during follow up of this type of tumor.

Cloning and nucleotide sequence of the pullulanase gene of Thermus thermophilus HB8 and production of the enzyme in Escherichia coli

A 3.4-kb SphI fragment carrying the pullulanase gene of Thermus thermophilus HB8 was cloned. Based on the nucleotide sequence of it and the flanking region analyzed by direct sequencing of the inverse PCR product, an expression vector was constructed. The E. coli cells harboring the plasmid produced an about 80-kDa protein having pullulanase activity, the optimum temperature of which was 70 degrees C.

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.

Direct intra-cardiomuscular transfer of beta2-adrenergic receptor gene augments cardiac output in cardiomyopathic hamsters

In chronic heart failure, down-regulation of beta-adrenergic receptor (beta-AR) occurs in cardiomyocytes, resulting in low catecholamine response and impaired cardiac function. To correct the irregularity in the beta-AR system, beta-AR gene was transduced in vivo into failing cardiomyocytes. The Epstein-Barr virus (EBV)-based plasmid vector carrying human beta2-AR gene was injected into the left ventricular muscle of Bio14.6 cardiomyopathic hamsters whose beta-AR is down-regulated in the cardiomyocytes. The echocardiographic examinations revealed that stroke volume (SV) and cardiac output (CO) were significantly elevated at 2 to 4 days after the beta2-AR gene transfer. Systemic loading of isoproterenol increased the cardiac parameters more significantly on day 2 to day 7, indicating that the adrenergic response was augmented by the genetic transduction. The same procedure did not affect the cardiac function of normal hamsters. Immunohistochemical examinations demonstrated human beta2-AR expression in failing cardiomyocytes transduced with the gene. RT-PCR analysis detected mRNA for the transgene in the heart but not in the liver, spleen, or kidney. The procedures may provide a feasible strategy for gene therapy of severe heart failure. Gene Therapy (2000) 7, 2087-2093.

Transurethral holmium laser resection of the prostate

PURPOSE

We evaluated the efficacy of the holmium:YAG laser for transurethral endoscopic prostatectomy for benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

We treated 103 patients with BPH with holmium:YAG laser resection of the prostate. A high power holmium laser generating a maximum of 60 or 81 W. was used in a pulsed mode, applying energy directly to prostatic tissue via a forward firing 550 micron. fiber transurethrally under direct vision. Treatment outcome was evaluated by the International Prostate Symptom Score, quality of life score, maximum flow rate and post-void residual urine volume. We also compared holmium laser surgery and transurethral resection of the prostate for operative factors, such as surgical duration, bleeding volume and catheterization time.

RESULTS

Average symptom score, quality of life score, peak flow rate and post-void residual significantly improved at 1 week, 1 month and 3 months postoperatively, with improvement maintained up to 36 months postoperatively in the holmium:YAG group. Intraoperative bleeding volume was significantly lower and catheterization time was significantly shorter for holmium:YAG than for transurethral prostatic resection. Use of the holmium laser caused no complications.

CONCLUSIONS

Because of its effectiveness and safety holmium:YAG resection is a viable potential surgical alternative for symptomatic BPH. The holmium:YAG laser has been verified to be useful for many purposes in urology.

Endoscopic lithotripsy with the holmium:YAG laser

BACKGROUND AND OBJECTIVE

The holmium:YAG (Ho:YAG) laser can be used not only for soft tissue but also for hard tissue such as urinary calculi. The objective of this study was to assess the usefulness of the Ho:YAG laser for endoscopic lithotripsy in patients with urinary tract stone. STUDY DESIGN/MATERIASL AND METHODS: Of 102 procedures performed among 96 patients, 88 were transurethral ureterolithotripsy (TUL), seven were percutaneous nephrolithotripsy, and seven were transurethral cystolithotripsy. Six patients had bilateral stones. The fragments were reduced as much as possible with the Ho:YAG laser.

RESULTS

The efficacy rate of the 102 lithotripsy procedures was 93%. With respect to the effect of TUL, the efficacy rates of 40 procedures for the proximal ureter, 18 procedures for the midureter, and 30 procedures for the distal ureter were 85%, 94%, and 100%, respectively.

CONCLUSION

The Ho:YAG laser produced a sufficiently strong lithotripsy force on all stones. The results of this study indicate that lithotripsy of urinary tract stones with the Ho:YAG laser can achieve a clinical outcome equivalent to or exceeding that of pulsed dye laser lithotripsy. The Ho:YAG laser is a multipurpose laser and thus is a cost effective and very useful means for endoscopic lithotripsy of urinary tract stones.

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.

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 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.

Gene transfer in vitro and in vivo with Epstein-Barr virus-based episomal vector results in markedly high transient expression in rodent cells

The EBV-based plasmid vectors, which carry oriP and EBNA1 gene from EBV genome, can be retained in the nucleus and replicate in human cells. Rodent cells are not permissive for the EBV plasmids, in terms of the plasmid replication. However, the EBV vector facilitates not only the long term maintenance of the plasmid but also high level gene expression at a transient phase after transfection. It has not been elucidated if rodent cells show this high level transient expression. We demonstrate that rodent cells transfected with an EBV vector expressed a marker gene more intensively than those with a conventional plasmid vector did. The high marker gene expression was also seen in rat myocardium injected in vivo with the EBV plasmid. The present data indicate that the EBNA1-oriP system functions in "non-permissive" rodent cells at transient phase, and may require different cellular factor(s) for the transient expression and plasmid replication.

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.

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.

Olive oil increases the magnitude of postprandial chylomicron remnants compared to milk fat and safflower oil

OBJECTIVE

The acute effects of olive oil, milk fat and safflower oil on postprandial lipemia and remnant lipoprotein metabolism were investigated.

METHODS

Eight Healthy male volunteers randomly underwent three types of oral fat-vitamin A loading tests. The test drink was a mixture of retinyl palmitate (RP)(50,000 IU of aqueous vitamin A/m2 body surface area) and one of the three types of oils (40 g of fat/m2 body surface area): olive oil (70.7% oleic acid of total fatty acids); milk fat (69.3% saturated fatty acid); safflower oil (74.2% linoleic acid).

RESULTS

Olive oil significantly increased plasma triacylglycerol and RP concentrations 4 hours after fat loading, as compared to other fats. Increases of remnant like particle concentrations were higher after olive oil than after the other two fats.

CONCLUSION

These results show that olive oil increases the magnitude of postprandial chylomicrons and chylomicron remnants compared to milk fat and safflower oil.

Efficient gene transduction by Epstein-Barr-virus-based vectors coupled with cationic liposome and HVJ-liposome

We show here a novel non-viral strategy to transduce human cells by using an EBV-based vector system. The EBV-based vectors, the plasmid vectors carrying EBV oriP (origin for plasmid replication) and EBNA (EBV nuclear antigen) 1 gene from EBV genome, were combined with 2 gene delivery systems, i.e., cationic liposome and HVJ-liposome. By both methods, EBV-based vectors could be more efficiently transfected into HeLa cells than non-EBV, conventional plasmid vectors. When human primary fibroblasts were transfected, EBV-based vectors coupled with cationic liposome but HVJ-liposome resulted in successful gene transduction, while human bone marrow cells were transduced with both HVJ-liposome- and cationic liposome-EBV vectors. These results suggest the potential applications of the EBV-based vector system for gene therapy.

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.

[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.

[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.

Study on brain interstitial fluid distribution and blood-brain barrier transport of baclofen in rats by microdialysis

PURPOSE

This study was performed to examine the distribution in the brain interstitial fluid (ISF) and the blood-brain barrier (BBB) transport of baclofen in rats by a microdialysis technique.

METHODS

Following an i.v. bolus administration and/or the constant i.v. infusion of baclofen to the microdialysis cannula-bearing anesthetized rats, the concentrations of baclofen in the hippocampal ISF, whole brain tissue, cerebrospinal fluid (CSF), and plasma were determined by high-performance liquid chromatography (HPLC). Data were kinetically analyzed to estimate the transport parameters, i.e., the influx clearance (CLin) from plasma to brain and the efflux rate constant (keff) from brain to plasma, and the steady-state volume of distribution in the brain (Vd).

RESULTS

The concentrations of baclofen in ISF, whole brain tissue, and CSF at the pseudo-steady state were almost 30-fold lower than the plasma unbound concentration, suggesting the restricted distribution of baclofen in the brain. The estimated values of CLin and keff were 0.00157 +/- 0.00076 ml/min/g of brain and 0.0872 +/- 0.0252 min-1, respectively. The efflux clearance (CLout) calculated by multiplying keff by Vd (0.816 +/- 0.559 ml/g of brain) was 0.0712 +/- 0.0529 ml/min/g of brain, and it was significantly 40-fold greater than the CLin value and fully greater than the convective flow in ISF. Furthermore, no significant concentration gradient was observed between ISF and CSF. These results suggest that the CLout value mainly reflects the efflux clearance through the BBB. Additionally, the hippocampal ISF/plasma concentration ratio of baclofen was markedly increased by both systemic administration of probenecid and its direct instillation into ISF.

CONCLUSIONS

The restricted distribution of baclofen in the brain ISF may be ascribed to the efficient efflux from the brain through the BBB which is regulated possibly by a probenecid-sensitive organic anion transport system.

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.

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.

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.

Enzyme-cytochemical study of small ganglion cells in experimental thiamine deficiency: concerning the pain mechanism

In an effort to clarify the mechanism of pain accompanying thiamine deficiency, thiamine monophosphatase (TMPase) activity was demonstrated, by means of electron microscopic cytochemistry, in small ganglion cells in pyrithiamine-treated thiamine-deficient rats. TMPase activity was seen to be present in the reticular part of the Golgi complex and vesicle-like bodies around the trans side of the Golgi complex. By the 10th day after the initial pyrithiamine treatment, a significant increase in the number of TMPase-positive vesicle-like body was observed. These results indicate that thiamine deficiency causes a disturbance in the transportation and/or production of TMPase, which is an integral part of the synaptic transmission of the nociception impulses.

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.