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Biomedical subjects

K Mori

Publications and source records attributed to K Mori.

At least 127 records · Page 7Linked to original sources
PubMed2001

Regional magnetic resonance spectroscopy of the brain in autistic individuals.

We studied the variations in the concentration of metabolites with brain region and age in autistic individuals and normal controls using multiple analysis of covariance. We examined 55 autistic individuals (2-21 years old, 47 male and eight female) and 51 normal children (3 months-15 years old, 26 boys and 25 girls). Single volumes of interest were placed in the frontal, parietal and temporal region on both sides, the brain stem and cingulate gyrus. The concentration of each metabolite was quantified by the water reference method. The concentration of N-acetylaspartate in the temporal regions (Brodmann's areas 41 and 42) in the autistic individuals were significantly lower than those in the controls (P < 0.05), but concentrations in other regions were not significantly different between the autistic individuals and controls. This suggests low density or dysfunction of neurones in Brodmann's areas 41 and 42 in autistic individual, which might be related to the disturbances of the sensory speech centre (Wernicke's area) in autism.

Adolescent↗
PubMed2001

Prenatal MR findings in a case of aneurysm of the vein of Galen.

We describe a case of aneurysm of the vein of Galen (AVG), which was diagnosed by intrauterine US, MRI and MRA. The baby girl was born at 35 weeks' gestation. She had severe clinical symptoms at birth and died at 29 h of age from intractable congestive heart failure. Intrauterine US detected an intracranial aneurysm and cardiomegaly due to excessive arteriovenous shunting. Intrauterine MRI (SSFSE) confirmed the diagnosis of AVG, and intrauterine MRA (2D-TOF) successfully demonstrated the anatomical structure of the AVG. MRA may be a useful additional sequence to evaluate AVG, and 2D-TOF is thought to be an appropriate technique for scanning fetal AVG.

Adult↗
PubMed2001

Design of PCR primers and a gene probe for extensive detection of poly(3-hydroxybutyrate) (PHB)-degrading bacteria possessing fibronectin type III linker type-PHB depolymerases.

For rapid and sensitive detection of poly(3-hydroxybutyrate) (PHB)-degrading bacteria, a PCR primer set (PHB primers) and a gene probe (PHB probe) were designed, based on the homologous regions of six fibronectin type III linker domain-encoding sequences laid on a variety of PHB depolymerase genes listed in the GenBank. PCR using PHB primers amplified DNA fragments with the expected sizes from all the tested bacterial strains used for primer design; and all of the amplified fragments gave positive signals by Southern hybridization with the PHB probe. No amplified fragments were observed from negative controls. To evaluate the availability of the PHB primers and PHB probe, they were applied to 57 wild-type, PHB-degrading bacteria newly isolated from a variety of environments. The PHB primers amplified DNA fragments with expected sizes from 50 of the 57 wild-type strains, while the PHB probe showed positive signals against the amplified fragments from 47 strains. These results suggest that the primer and probe system established in this study can detect a considerable proportion of the potential PHB-degrading bacteria and can be applied to evaluate PHB-degradation potential in a natural environment, in combination with direct DNA extraction methods.

Bacteria↗
PubMed2001

Micron, a microsatellite-targeting transposable element in the rice genome.

We have isolated a new family of mobile elements, Micron, which occur within microsatellites dispersed throughout the rice (Oryza sativa) genome. The first of these segments, Micron 001, was found in a microsatellite consisting of a (TA)n sequence upstream of the rice phytochrome A (phyA) gene. PCR analysis of related rice species suggests that Micron 001 integrated into this microsatellite locus prior to the divergence of the two wild species O. rufipogon and O. barthii from a common ancestor. Micron elements are short (393-bp), possess subterminal inverted repeats and the single strands have the potential to form stable secondary structures via several internal repeats. Aside from the absence of terminal inverted repeats, these characteristics resemble those of MITEs (Miniature Inverted-Repeat Transposable Elements). We estimate that 100-200 copies of Micron-related sequences are present in the rice nuclear genome, while the chloroplast and mitochondrial genomes lack this sequence. Nineteen homologs of Micron 001 exhibited extremely high nucleotide sequence conservation (greater than 90%), suggesting a recent spread of Micron elements within the genus Oryza. Surprisingly, nucleotide sequence alignments showed that all of the Micron elements are flanked on both sides by microsatellite sequence consisting mainly of (TA)n. Twenty-three elements were mapped to seven separate chromosomes. Therefore Micron elements form a family of dispersed, highly conserved repeats. This is the first report of a transposable element that targets microsatellite loci.

Amino Acid Sequence↗
PubMed2001

Kyphotic malalignment after anterior cervical fusion is one of the factors promoting the degenerative process in adjacent intervertebral levels.

The aim of this study was to determine whether postoperative malalignment of the cervical spine after anterior interbody fusion surgery promotes degenerative changes in the neighboring intervertebral discs. Forty-two patients who underwent anterior interbody fusion surgery for cervical spondylosis and disc herniation (34 men, 8 women) were followed for an average of 9.8 years. The average age at surgery was 50.2 years. Twenty-three patients underwent a single-level fusion, 17 underwent two-level fusion, and 2 had three levels fused. The Japanese Orthopaedic Association cervical myelopathy score, with a normal score 17 points, was 11.7 before surgery and 14.9 at follow-up. Neurological status was significantly improved postoperatively, and the improvement was preserved thereafter in most cases (paired t-test, P<0.001). Degenerative changes were evident on radiological examination in the levels adjacent to the fused segment in 21 of the 42 (50%) patients. Eight of these 21 patients demonstrated neurological deterioration caused by an adjacent disc lesion. A total of 43% of the patients with adjacent-level degeneration had malalignment of the cervical spine, such as kyphosis or sigmoid curvature. In addition, degenerative change in adjacent intervertebral levels was observed in 77% of kyphoses of the fused segment. These were statistically significant (Fisher exact method, P<0.05, P<0.04, respectively). Our findings suggest that one of the factors promoting degenerative change in adjacent intervertebral levels after anterior cervical fusion for degenerative disorders is postoperative kyphotic change in the cervical spine and the fused segment.

Cervical Vertebrae↗
PubMed2001

Aggressive decompressive surgery in patients with massive hemispheric embolic cerebral infarction associated with severe brain swelling.

Massive hemispheric cerebral infarction, also known as malignant infarction, is characterized by rapid clinical deterioration due to brain swelling and downward transtentorial herniation, and is associated with a mortality of 80%. Early patient selection and establishment of the optimum therapeutic modality are important to improve the outcome. Early clinical, computed tomography (CT), and angiographic characteristics were analysed to identify patients with malignant infarction and external and internal decompression was performed, with unco-parahippocampectomy if needed, and the outcomes were compared with those of conservative treatment. Thirty-four of 55 patients admitted with large cerebral infarctions due to embolism showed rapid clinical deterioration due to brain swelling and herniation. These 34 patients were treated under a diagnosis of malignant infarction by decompressive surgical treatment (19 cases) or conservative treatment (15 cases). CT showed significantly higher infarction volume in patients with malignant infarction (288 +/- 62 cm3) compared to patients with non-malignant infarction (200 + 57 cm3, P < 0.001) and angiography showed a higher incidence of recanalization of the occluded vessels in patients with malignant infarction (58%) compared to patients with non-malignant infarction (15%, P < 0.05). Discriminant analysis revealed that an infarction volume of more than 240 cm3 was predictive of malignant infarction with 76.4% accuracy. Basic clinical characteristics on admission and deterioration were not statistically different between the surgically treated and conservatively treated groups of patients with malignant infarction. The shift of midline structures was significantly improved (14 +/- 3.5 to 10 +/- 4.7 mm) after surgical treatment (P < 0.05). compared to deterioration (12 +/- 5.8 to 15 +/- 4.5 mm) after conservative treatment. The mortality was 67% in the conservative group and 16% in the surgical group. Surgical treatment significantly improved the mortality and Glasgow Outcome Scale score (P < 0.01). However, the mean Barthel Index scores of the survivors were not significantly different. An infarct volume of more than 240 cm3 on CT and angiographic recanalization of the occluded artery are predictors of fatal brain swelling after massive cerebral infarction. Decompressive surgical treatment dramatically improves the mortality of massive hemispheric infarction.

Aged↗
PubMed2001

Inhibition of choroidal neovascularization by intravenous injection of adenoviral vectors expressing secretable endostatin.

Endostatin is a cleavage product of collagen XVIII that inhibits tumor angiogenesis and growth. Interferon alpha2a blocks tumor angiogenesis and causes regression of hemangiomas, but has no effect on choroidal neovascularization (CNV). Therefore, inhibitors of tumor angiogenesis do not necessarily inhibit ocular neovascularization. In this study, we used an intravenous injection of adenoviral vectors containing a sig-mEndo transgene consisting of murine immunoglobulin kappa-chain leader sequence coupled to sequence coding for murine endostatin to investigate the effect of high serum levels of endostatin on CNV in mice. Mice injected with a construct in which sig-mEndo expression was driven by the Rous sarcoma virus promoter had moderately high serum levels of endostatin and significantly smaller CNV lesions at sites of laser-induced rupture of Bruch's membrane than mice injected with null vector. Mice injected with a construct in which sig-mEndo was driven by the simian cytomegalovirus promoter had approximately 10-fold higher endostatin serum levels and had nearly complete prevention of CNV. There was a strong inverse correlation between endostatin serum level and area of CNV. This study provides proof of principle that gene therapy to increase levels of endostatin can prevent the development of CNV and may provide a new treatment for the leading cause of severe loss of vision in patients with age-related macular degeneration.

Adenoviridae↗
PubMed2001

Quantitative Analysis of Indocyanine Green Angiographic Image in Central Serous Chorioretinopathy.

Purpose: To disclose the possible involvement of choroidal vascular change in developement of central serous chorioretinopathy (CSC).Methods: Indocyanine green (ICG) angiography was performed in 31 eyes with acute CSC, and 21 eyes from normal subjects. The maximum diameter of the choroidal veins and intensity of background fluorescence in the posterior fundus with ICG video images were measured for further analysis using IMAGEnet((R)) (Topcon). Then the results from CSC affected eyes, their fellow eyes, and normal eyes were compared. Aging factors were taken into consideration when we analyzed the data.Result: The maximum diameters of the choroidal veins were larger in both affected and fellow eyes than in the normal eyes (P <.001), and had a positive correlation with aging particularly in fellow eyes (r = 36). Both in the affected and fellow eyes, the background fluorescein intensity in the posterior pole of the late phase images was lower than in the normal eyes (P <.001), and was correlated with aging (r = 0.28, r = 0.43).Conclusion: This quantitative study showed that choroidal venous dilatation and the residual background fluorescence in the posterior fundus might be positive findings reflecting the pathogenesis of CSC.

Journal Article↗
PubMed2001

A minor E-selectin ligand, CD65, is critical for extravascular infiltration of acute myeloid leukemia cells.

Adhesive ligands on acute myeloid leukemic (AML) blasts may mediate transmigration and extravascular infiltration. In this study, 30 AML samples were examined for expression and density of adhesion antigens. By univariate analysis, four patients with extravascular infiltration showed significantly higher expression of CD2, CD11a, CD11b, CD11c, CD15, CD65, CD86, and HLA-DR as compared with patients without infiltration. These four patients also showed significantly higher density of CD11a, CD11b, CD11c, CD15 and CD65 expression. By multivariate analysis, CD65 expression was the only significant independent risk factor for infiltration, suggesting that this is a critical adhesion molecule for extravascular AML infiltration.

Acute Disease↗
PubMed2001

Aminoguanidine prevented the impairment of learning behavior and hippocampal long-term potentiation following transient cerebral ischemia.

The present study was performed to investigate whether increases in nitric oxide (NO) production via inducible nitric oxide synthase (iNOS) were involved in impairment of learning behavior and hippocampal long-term potentiation (LTP) following transient ischemia. Rats with four-vessel occlusion (4-VO) were used as an ischemic model. One week after permanent occlusion of the vertebral arteries, the common carotid arteries were clamped for 10 min under halothane anesthesia. Aminoguanidine (10 mg/kg i.p.), a relatively selective iNOS inhibitor, or saline was administered 30 min before common carotid arteries occlusion, and every 24-h for 4 days. We investigated whether hippocampal NO production was increased by ischemic insult using microdialysis on days 1, 4 and 7 after 4-VO. On days 1 and 4 after 4-VO, increases in NO production were observed, and this effect was inhibited by aminoguanidine. Four days after 4-VO, rats were subjected to the Y-maze test and contextual fear conditioning. Ischemic insults impaired learning behavior, and aminoguanidine ameliorated the impairment induced by 4-VO. Four days after 4-VO, the changes in the population spike amplitude were recorded as an index of LTP in Schaffer collateral-CA1 (carotid artery 1), the mossy fiber-CA3 and the perforant path-dentate gyrus synapses. LTP was significantly inhibited by 4-VO, except in mossy fiber-CA3 synapses. Pretreatment with aminoguanidine prevented the reduction of LTP in perforant path-dentate gyrus, but not in Schaffer collateral-CA1 synapses. These results suggest that post-ischemic increase in NO production via iNOS impaired the learning behavior. There is an association between behavioral performance and LTP formation in perforant path-dentate gyrus synapses, but neither in Schaffer collateral-CA1 nor in mossy fiber-CA3 synapses.

Animals↗
PubMed2001

Physiological and morphometric analyses of neuropathy in sucrose-fed OLETF rats.

To investigate the characteristic features of diabetic neuropathy in type 2 diabetes mellitus, Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of human type 2 diabetes mellitus, and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats were fed with or without sucrose and/or an aldose reductase inhibitor, [5-(3-thienyl) tetrazol-1-yl] acetic acid (TAT), for 24 weeks, and physiological, biochemical and morphological assessments were performed. Sucrose administration caused remarkable hyperglycemia in OLETF rats but not in LETO rats. Sucrose-fed OLETF rats demonstrated delayed nerve conduction velocity, decreased coefficient of variation of R-R interval, reduced sciatic nerve blood flow, increased platelet aggregation activity, a lower concentration of erythrocyte 2,3-diphosphoglycerate, and decreased Na+/K+-ATPase activity in sciatic nerves, compared with the non-sucrose-fed OLETF and LETO rats. TAT prevented all these deficits except hyperglycemia. Sorbitol and fructose accumulation and myo-inositol depletion in tail nerves of sucrose-fed OLETF rats were ameliorated by TAT. Myelinated fiber size and density in sural nerves of sucrose-fed OLETF rats were decreased and increased, respectively, compared with non-sucrose-fed OLETF and LETO rats. These morphological abnormalities were normalized by TAT. These observations suggest that the sucrose-fed OLETF rat developed diabetic neuropathy not only electrophysiologically but also histologically, and that an aldose reductase inhibitor, TAT, possesses therapeutic value for the treatment of diabetic neuropathy.

2,3-Diphosphoglycerate↗
PubMed2001

Role of adrenomedullin and its receptor system in renal pathophysiology.

Adrenomedullin (AM), a potent vasorelaxing, natriuretic and cell growth-modulating peptide, is thought to act as an autocrine/paracrine regulator in renal glomeruli and tubules. AM receptors comprise the calcitonin receptor-like receptor (CRLR) and a family of receptor-activity-modifying proteins (RAMPs 1-3); however, the pathophysiological role of AM and its receptor system in the kidney remains to be clarified. We examined the regulation of their expression in a rat model of renal injury and found that RAMP1, RAMP2 and CRLR expressions were markedly upregulated upon induction of fibrosis during obstructive nephropathy. Since AM exerts potent antiproliferative effects in various cell types, upregulation of the AM receptor system may play important roles in modulating the progression of renal diseases.

Adrenomedullin↗
PubMed2001

Laboratory data and treatment outcomes of head and neck tumor patients in the elderly.

OBJECTIVE: To elicit the factors influencing the choice of treatment and the prognosis of elderly patients, we studied the clinical and laboratory data of head and neck tumor patients. The patients were divided into two groups (group A: younger than 75, group B: 75 years of age or older) and the treatment outcomes as well as the features of the laboratory data were analyzed. METHODS: The clinical records of 1350 patients (888 males, 462 females) with head and neck tumors who received their initial treatment at our hospital were reviewed. The collected data including age, the site of the primary lesion, pre-treatment health states, pre-operative laboratory results were examined. According to the treatment policy, we grouped the patients according to whether or not they had received the standard therapy for the disease and then analyzed their treatment outcomes. RESULTS: Standard therapy was not performed in 62 (5.6%) of the 1114 patients in group A and in 43 (18.2%) of the 236 patients in group B. A further analysis performed in group B (elderly patients) revealed that standard therapy was performed in 193 patients, while 43 received non-standard therapy. The prognosis for the non-standard therapy cases was poor. The averages of the laboratory test findings between groups A and B were compared, but no marked differences were observed. However, differences were observed in the ratio of patients whose data were in the normal range between group A and group B. When the laboratory data were compared between the standard and non-standard groups of the elderly, serum albumin and CBC (especially hemoglobin) showed a close relationship to the treatment modality. CONCLUSION: The ratio of patients who did not receive standard therapy was high in the age group of 75 years or older. The prognosis of patients with head and neck tumors is therefore considered to depend on whether or not a patient receives the standard therapy against the disease. The pre-treatment clinical data and the laboratory findings vary markedly among elderly patients 75 years of age or older. Regarding the treatment of head and neck tumors in the elderly, the laboratory data and clinical conditions of each individual patient should be checked carefully and every possible means should be employed in order to allow such patients to receive the standard therapy whenever possible.

Adult↗
PubMed2001

Vascular cell adhesion molecule-1 as a biochemical marker of left ventricular mass in the patients with hypertension.

Plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1), vascular adhesion molecule-1 (sVCAM-1), and E-selectin were measured in 80 outpatients with uncomplicated essential hypertension. Although the levels of E-selectin and sICAM-1 were similar between the patients with and without left ventricular (LV) hypertrophy, sVCAM-1 level was significantly elevated in the patients with LV hypertrophy (759.7+/-154.6 ng/mL nu 984.4+/-240.6 ng/mL, P < .0001). The LV mass normalized to body surface area or height were significantly correlated with sVCAM-1 (r=0.615, P < .0001 and r=0.571, P < .0001, respectively). These results indicate that a soluble adhesion molecule is correlated with LV mass in uncomplicated essential hypertensive patients.

Aged↗
PubMed2001

Determination of tetrahydrobiopterin in murine locus coeruleus by HPLC with fluorescence detection.

Tetrahydrobiopterin in the murine locus coeruleus was measured as its fully oxidized form, biopterin, using a HPLC coupled to a fluorescence detector, because tetrahydrobiopterin itself cannot be detected by such means. The differential oxidization method distinguished tetrahydrobiopterin-derived biopterin and dihydrobiopterin-derived biopterin. The protocol reported here is a rapid and sensitive method that facilitates the measurement of tissue and/or cellular tetrahydrobiopterin. Using this assay protocol, we were able to detect and quantify variations in the tetrahydrobiopterin content in the murine locus coeruleus.

Animals↗
PubMed2001

Ectopic atrial tachycardia due to aneurysm of the right atrial appendage.

We report an infant with ectopic atrial tachycardia, due to an aneurysm of the right atrial appendage, who developed congestive heart failure. Although catheter ablation was transiently successful, tachycardia recurred 2 days later. The aneurysm of the right atrial appendage was resected successfully by surgery, and thereafter she did well, reverting to normal sinus rhythm.

Atrial Appendage↗
PubMed2001

Does pheromone biology of Lambdina athasaria and L. pellucidaria contribute to their reproductive isolation?

Recently, 7-methylheptadecane and 7,11-dimethylheptadecane have been reported as sex pheromone components of both spring hemlock looper (SHL), Lambdina athasaria, and pitch pine looper (PPL), Lambdina pellucidaria. Our objective was to test the hypothesis that SHL and PPL are reproductively isolated, in part, through species specificity in: (1) absolute configuration of pheromone components, (2) diel periodicity of pheromonal communication, and/or (3) seasonal flight period. In coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of stereoselectively synthesized (7S)- and (7R)-7-methylheptadecane [7S; 7R] as well as (7S,11S)-, (7R,11R)-, and (meso-7,11)-7,11-dimethylheptadecane [7S,11S; 7R,11R; meso-7,11], only 7S and meso-7,11 elicited responses by male SHL and PPL antennae. In field experiments, male SHL and PPL were attracted only to lures containing 7S plus meso-7,11. In hourly recordings of trap-captured males, SHL and PPL in their respective habitats were trapped between 24:00 and 03:00 hr. Capture of both SHL and PPL in pheromone-baited traps throughout June indicated overlapping seasonal flight periods. These findings of identical absolute configuration of pheromoal components, diel periodicity of pheromonal communication, and overlap of seasonal flight periods support synonymy of SHL and PPL. Finite taxonomic classification of PPL and SHL must await careful assessment of further criteria, such as morphometrics, molecular comparisons and ecological analyses.

Animals↗