Characterization of a new animal model of metabolic syndrome: the DahlS.Z-Lepr(fa)/Lepr(fa) rat.

OBJECTIVE: The DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rat strain was established from a cross between Dahl salt-sensitive rats and Zucker fatty (fa/fa) rats, the latter of which harbor a missense mutation in the leptin receptor gene (Lepr). We examined whether DS/obese rats might be a suitable animal model of metabolic syndrome in humans. METHODS: The systemic pathophysiological and metabolic characteristics of DS/obese rats were determined and compared with those of homozygous lean littermates, namely, DahlS.Z-Lepr(+)/Lepr(+) (DS/lean) rats. RESULTS: Systolic blood pressure was higher in DS/obese rats fed a normal diet than in DS/lean rats at 11 weeks of age and thereafter. The survival rate of DS/obese rats was significantly lower than that of DS/lean rats at 18 weeks. Body weight, visceral and subcutaneous fat mass, as well as heart, kidney and liver weights, were increased in DS/obese rats at 18 weeks compared with DS/lean rats. Serum low-density lipoprotein (LDL)-cholesterol, triglyceride and insulin concentrations, as well as the ratio of LDL-cholesterol to high-density lipoprotein-cholesterol levels, were increased in DS/obese rats, whereas serum glucose concentration did not differ significantly between DS/obese and DS/lean rats. Creatinine clearance was decreased and urinary protein content was increased in DS/obese rats, which also manifested lipid accumulation in the liver and elevation of serum alanine aminotransferase levels. CONCLUSION: These results show that the phenotype of DS/obese rats is similar to that of humans with metabolic syndrome, and that these animals may thus be an appropriate model for this condition.

IFNß-1b may severely exacerbate Japanese optic-spinal MS in neuromyelitis optica spectrum.

BACKGROUND: Interferon-ß-1b (IFNß-1b) has been used to prevent exacerbation of relapsing-remitting multiple sclerosis (RRMS) including optic-spinal multiple sclerosis (OSMS) in Japan. We encountered 2 patients with OSMS with unexpectedly severe exacerbation soon after the initiation of IFNß-1b therapy. The experience urged us to retrospectively review the patients with RRMS who had been treated with IFNß-1b to identify similar cases. METHODS: At neurologic departments of 9 hospitals, the medical records of 56 patients with RRMS were reviewed to identify those who showed severe exacerbation soon after the initiation of IFNß-1b therapy. RESULTS: Of 56 patients with RRMS, we identified 7 who experienced severe exacerbation (exacerbation with increased scores of Expanded Disability Status Scale ≧7.0) within 90 days of the initiation of IFNß-1b therapy. In all 7 patients, the exacerbations after the initiation of IFNß-1b therapy were more severe than those experienced by the individual patients before the use of IFNß-1b, and seemed to have occurred unexpectedly in a short time after the initiation of INFß-1b therapy. A retrospective analysis revealed that all 7 patients had antibodies toward aquaporin 4, and the clinical features of all 7 patients after the exacerbation were consistent with those of neuromyelitis optica (NMO) spectrum. CONCLUSIONS: Our study suggests that IFNß-1b may trigger severe exacerbation in patients with the NMO spectrum. In INFß-1b therapy, cases in NMO spectrum should be carefully excluded.

Hypermethylation of CpGs in the promoter of the COL1A1 gene in the aged periodontal ligament.

Although the human periodontal ligament shows age-associated histological alterations, the molecular mechanisms are not yet understood. We previously found that COL1A1 gene expression declines with age. In this study, we asked whether DNA methylation in the regulatory region of the gene alters in the aging process, as a possible cause of the decline. The method used was a bisulfite modification of cytosine and nucleotide sequencing of DNA. While the 1st intron region was kept demethylated at young and old ages, the levels of methylation at most CpG sites in the proximal and distal regions of the promoter showed elevation at older ages. Analysis of the data indicates the possible importance of DNA hypermethylation in the promoter region for the age-associated decrease of COL1A1 gene expression.

Few-electron molecular states and their transitions in a single InAs quantum dot molecule.

We study electronic configurations in a single pair of vertically coupled self-assembled InAs quantum dots, holding just a few electrons. By comparing the experimental data of nonlinear single-electron transport spectra in a magnetic field with many-body calculations, we identify the spin and orbital configurations to confirm the formation of molecular states by filling both the quantum mechanically coupled symmetric and antisymmetric states. Filling of the antisymmetric states is less favored with increasing magnetic field, and this leads to various magnetic field induced transitions in the molecular states.

Treatment of experimental arthritis with poly(D, L-lactic/glycolic acid) nanoparticles encapsulating betamethasone sodium phosphate.

OBJECTIVE: To examine the therapeutic activity of hydrophilic glucocorticoid encapsulated in PLGA nanoparticles, which have shown slow release and are targeted to inflamed joints after intravenous administration, in experimental arthritis models. METHODS: Betamethasone sodium phosphate (BSP) encapsulated in PLGA nanoparticles with a size of 100-200 nm (PLGA-nanosteroid) was prepared using a modified oil in water emulsion solvent diffusion method with Zn ions and coated with lecithin. Rats with adjuvant arthritis (AA rats) and mice with anti-type II collagen antibody induced arthritis (AbIA mice) were treated intravenously with PLGA-nanosteroid after the initial sign of arthritis. RESULTS: In AA rats, a 30% decrease in paw inflammation was obtained in 1 day and maintained for 1 week with a single injection of 100 mug of PLGA-nanosteroid. Soft x ray examination 7 days after this treatment showed decreased soft tissue swelling. Moreover, the PLGA-nanosteroid was also highly effective in AbIA mice. A single injection of 30 mug of the PLGA-nanosteroid resulted in almost complete remission of the inflammatory response after 1 week. In contrast, the same dose of free BSP after three administrations only moderately reduced the severity of inflammation. In addition, a histological examination 7 days after the treatment showed a significant decrease of the inflammatory cells in the joints. CONCLUSION: The observed strong therapeutic benefit obtained with PLGA-nanosteroid may be due to the targeting of the inflamed joint and its prolonged release in situ. Targeted drug delivery using a sustained release PLGA-nanosteroid is a successful intervention in experimental arthritis.

Secretion of natriuretic peptides caused by an epileptic attack.

OBJECTIVE: To describe clinical features of a patient with secretions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) during an epileptic attack. PATIENT: A 65-year-old woman experienced frequent bouts of polyuria, pyrexia and general fatigue after several years of a cerebral contusion involving the left fronto-temporal lobe caused by a traffic accident. Her urine output and urinary sodium excretion increased, and plasma ANP and BNP concentrations were markedly high during each attack. Electroencephalography (EEG) showed serial seizure discharge in the left anterior temporal region during the attacks, indicative of epileptic focus. CONCLUSION: ANP and BNP secretions probably were triggered by epileptic stimulation on the diencephalon beyond the focus.

Diimide-enhanced fingerprint detection with photoluminescent CdS/dendrimer nanocomposites.

The chemical development of latent fingerprints by nanocomposites that involve photoluminescent cadmium sulfide nanoparticle aggregates with Starburst dendrimer is demonstrated. The dendrimer bonds to fingerprint residue via its terminal functional groups. When these are amino groups (generation 4 dendrimer), the binding is enhanced by fingerprint pre-treatment with diimide. The diimide converts carboxylic acid moieties of the fingerprint residue to esters that then react with the dendrimer amino groups to form amide linkages. The cadmium sulfide/generation 4 dendrimer development of fingerprints is enhanced by elevated temperature also. Finally, fingerprint development with carboxylate-functionalized cadmium sulfide/generation 3.5 dendrimer nanocomposites is examined. Here, diimide treatment of the dendrimer itself aids the subsequent fingerprint labeling, which involves amino acid of the figerprint residue. Nanocomposite fingerprint detection is compatible with time-resolved imaging for background fluorescence elimination.

[Spinal cord infarction presenting Brown-Séquard syndrome with impaired position sense].

A 79-year-old hypertensive man presented left hemiplegia of sudden onset. Neurological examination revealed weakness of the left extremities, with hypoalgesia on the opposite side below the level C 4. He also showed Horner syndrome, facial hypoalgesia, weakness of sternocleidmastoid and trapezius muscles on the paralyzed side. The position and vibration senses were impaired on the left extremities. The position sense was more disturbed on his upper limb, to the extent that the patient was not able to recognize where his wrist was located. The cervical MRI exhibited a high signal intensity on the left half of the cord between C 2-C 5 vertebral level on T 2 WI. Bilateral vertebral arteries were patent, though severe stenosis of internal-external carotid artery bifurcation was observed on MRA. Asymmetrical distribution of upper cervical cord arteries, severe atherosclerotic change of cervical and intracranial vessels, and spondylotic cervical canal stenosis were suggested to contribute to cause the lateralized infarction of the cord, involving not only the anterior, but also posterior part, where Burdach's fascicle were probably more affected.

Photoluminescent CdS/dendrimer nanocomposites for fingerprint detection.

CdS/dendrimer nanocomposites with a range of concentrations of the photoluminescent semiconductor nanocluster and the dendrimer are prepared in methanol and 1:9 methanol:water solutions. The solutions are utilized for detection of cyanoacrylate ester fumed and unfumed fingerprints on polyethylene and aluminum foil.

Distribution of spontaneous CpG-associated G:C --> A:T mutations in the lacZ gene of Muta mice: effects of CpG methylation, the sequence context of CpG sites, and severity of mutations on the activity of the lacZ gene product.

In our previous study using transgenic Muta mice, G:C --> A:T transitions at 5'-CG-3' (CpG) sites, which are the most common mammalian spontaneous mutation, were detected in 197 of 330 spontaneous lacZ mutants. These transitions were recovered at only 27 of the 357 mutable G:C pairs within CpG sites where the transition could produce a missense or termination codon in the lacZ gene. To address the underlying mechanism for the uneven distribution of mutated CpG sites, the CpG methylation status of the Muta lacZ gene was analyzed by a bisulfite method. All the CpG sites examined in the coding region were evenly methylated at a high level, and no site-specific methylation was evident. Analysis of the sequence context around the mutated CpG sites, however, revealed that 21 of these 27 sites contained a CpG flanked by a pyrimidine on the 5' side, and that 187 of the 197 mutants resulted from substitutions at these sites. Moreover, we found five hotspots among those sites, the location of which was intimately related to the enzymatic activity of the gene product: one site produced a nonsense codon; three sites, one of which corresponded to the nucleophile at the active site, resided in the substrate-binding pocket; and the other site was located in a region conserved in the beta-galactosidase family. These results strongly suggest that recovery of lacZ mutations at each site largely depend on the adjacent sequence context and the extent to which the mutation damages the enzymatic activity of the gene product.

Age-dependent alterations in mRNA level and promoter methylation of collagen alpha1(I) gene in human periodontal ligament.

In an attempt to understand the molecular mechanisms of age-dependent degenerative alteration in human periodontal tissues, we examined mRNA level and DNA methylation of collagen alpha1(I) gene. Using healthy periodontal ligament tissues from humans aged 9-76 years, we found that the collagen alpha1(I) mRNA level decreased almost linearly with age. It was observed in both Northern blot and dot blot hybridization. Examination of DNA methylation in the collagen alpha1(I) gene promoter region by its susceptibility to methylation-sensitive restriction enzyme followed by Southern blot analysis showed age-dependent increase of DNA methylation at -1705 and -80 positions located upstream of the gene. The data suggest the possible importance of alterations in collagen alpha1(I) gene expression and its DNA methylation in promoter region in age-dependent degeneration of periodontal ligament.

Clinicopathological study of an autopsy case with sensory-dominant polyradiculoneuropathy with antiganglioside antibodies.

A previously reported patient presenting sensory-dominant neuropathy with antiganglioside antibodies, bound preferentially to polysialogangliosides including GD1b, was autopsied. While axonal degeneration was predominant in the sural nerve, many demyelinated fibers were present in the spinal roots. Dorsal roots had undergone significant damage. These pathological findings were well correlated with the electrophysiological results showing decreased F-wave conduction velocities and conduction blocks in motor nerves and decreased or absent sensory action potentials in sensory nerves, with distribution of GD1b in nerve tissues such as dorsal root ganglia and paranodal myelin in the ventral and dorsal roots.

Mechanically elicited nerve root discharge: mechanical irritation and waveform.

OBJECTIVE: Intraoperative monitoring is very important for protecting nerve roots during lumbar surgery for spinal degeneration. Our objective was to evaluate the correlation between the type of mechanical irritation and waveform by mechanically elicited EMGs during the surgery. METHOD: Mechanically elicited EMGs were recorded bilaterally on muscle groups innervated by the lumbar nerve roots in the area of surgery in 24 consecutive patients with lumbar spinal degenerative disease. RESULTS: It was confirmed that surgical irritation produced 3 types of waveforms as discharges from nerve roots; short, waning and continuous discharges. Each waveform was easily elicited mechanically and was sensitively related to the type and strength of mechanical stimulation. CONCLUSION: It was indicated that the mechanical irritation on the root could elicit the nerve root discharge with no post-operative nerve root deficit. It may be useful to monitor the mechanically elicited EMGs during the surgery for spinal degeneration.

Campylobacter fetus subsp. fetus cholecystitis in a patient with advanced hepatocellular carcinoma.

Acute cholecystitis due to Campylobacter fetus subsp. fetus is very uncommon. We report a case of cholecystitis and obstructive jaundice in which cultured bile grew this organism. The patient had a 4-year history of hepatocellular carcinoma, resulting in common bile duct obstruction due to abdominal lymph node metastasis. Microscopic examination of her bile showed multiple Gram-negative curved organisms and C. fetus subsp. fetus was isolated under microaerophilic conditions. Therefore, we should be aware of this organism and use microaerophilic culture in association with the result of microscopic examination of bile specimens.

[A case of Creutzfeldt-Jakob disease (CJD) started with monoparesis of the left arm].

A 72-year-old man developed a sudden weakness in his left hand on October 5, 1991. He was admitted two weeks thereafter. Physical examination revealed minimal weakness, and clumsiness of the fingers on his left hand. Exaggerated tendon reflexes and spasticity were also noted only on his left upper limb. He had neither dementia nor psychiatric symptoms. Subsequently he developed weakness in his left leg on November 17. Within 12 days he developed left facial weakness, and myoclonic movements on the left side. By December 2, he developed spastic tetraparesis with bilateral facial palsy, and generalized myoclonic jerks. A few days after that he started to show decorticate posture. From December 16, his mental status deteriorated rapidly, and he became mute, and uncooperative within a week. His clinical course can be summarized as stepwise progression similar to a cerebrovascular accident. Electroencephalography was normal on admission, but periodic synchronous discharge developed in January 1992. Brain CT that showed only mild brain atrophy at first was considered to be compatible with his age, changed to have severe brain atrophy in March 1992. He died of pneumonia on May 24, 1992 after eight months of progressive clinical course. Autopsy was done. The brain weighed 930 grams. Macroscopically there was prominent cortical atrophy. Microscopic examination revealed severe spongy state throughout the cerebral cortex. Typical spongiform changes were confined to the hippocampus. The cerebral white matter appeared to be normal. In the cerebellar cortex, the granular cell layer disappeared and Purkinje's cells were reduced in number. Kuru plaques were not seen. The cerebellar white matter, dentate nucleus, and brainstem seemed to be normal. The spinal cord was not examined. There were no pathological changes to indicate cerebrovascular accident, except for a lacuna in the right basal ganglion and a small angionecrosis in the pons. Western blotting test using Anti-APC (amyloid plaque core) antibody was positive. Neuropathological changes of the present case were consistent with those of CJD. However, the sudden onset of monoparesis without dementia or ataxia is rare as the initial symptom of this disease. The subsequent clinical course with stepwise progression of hemiplegia, which was mimicking a progressive stroke, was also rare for CJD. In comparison to typical case of CJD, this case had a different clinical onset as acute monoparesis. We can find such cases of CJD presenting as stroke in 5.6% in the previous English literatures.

[A case of Acanthamoeba keratitis after operation for cataract].

Acanthamoeba keratitis occurs mainly in contact lens users. We experienced a patient with Acanthamoeba keratitis after operation for cataract. A 70-year-old male, who suffered from suppurative keratitis with impairment of visual acuity and eye pain in the left eye after the operation, was admitted to our hospital. After admission he received treatment with oral and topical antibiotics without any improvement. Neither bacterial or fungal pathogens was detected from corenal skrappings. Blue stained Acanthamoeba cysts were detected with the Parker ink KOH preparation from punctured fluid of the anterior chamber of the eye. Acanthamoeba cysts were also cultured on a nonnurient agar plate with Escherichia coli. Then he was treated with oral and topical miconazole and topical fluconazole. His visual acuity did not improve because of the lag of appropriate treatment. Therefore, attention must be paid for the existence of Acanthamoeba keratitis after ophthalmologic operations.

Two species of antiganglioside antibodies in a patient with a pharyngeal-cervical-brachial variant of Guillain-Barré syndrome.

A patient with a pharyngeal-cervical-brachial variant of Guillain-Barré syndrome had anti-GT1a and anti-GD1a antibodies (IgG) in the serum. The activities of anti-GT1a antibodies were stronger than anti-GD1a antibodies and their activities declined later in the clinical course. These two different antibodies bound independently to each ganglioside in an absorption study with polystyrene beads coated with GT1a or GD1a.