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M Hayashi

Publications and source records attributed to M Hayashi.

At least 73 records · Page 4Linked to original sources
PubMed2004

Theoretical differential Raman scattering cross-sections of totally-symmetric vibrational modes of free pyridine and pyridine-metal cluster complexes.

The differential Raman scattering cross-sections of totally-symmetric vibrational modes for pyridine and pyridine-metal clusters have been calculated by using ab initio and density functional methods. The results are compared with experimental data and a good agreement is obtained. In particular, we can theoretically reproduce the significant changes in the relative Raman intensities of the nu(12) mode in pyridine-metal cluster complexes. We focus on two mechanisms for these Raman intensities changes: (1) the chemical interaction between the pyridine and the metal clusters; and (2) the charge transfer mechanism. For the pyridine-silver cluster complexes, we find that due to the weak bonding, the chemical interaction does not influence the relative intensities of the Raman peaks of the nu(1) and nu(12) modes. However, in the case where the copper or the gold clusters are attached to pyridine, the intensity of the band of the nu(12) mode is weakened significantly. We also find that the charge transfer mechanism increases the asymmetry of the bands of the nu(1) and nu(12) modes on all three metals.

Carbon↗
PubMed2004

Minimally invasive management of the third ventricle glioma in a patient without hydrocephalus: neurofiberscopic biopsy followed by gamma knife radiosurgery.

There is usually concern that ventricular enlargement is necessary for safe neuroendoscopic procedures. However, newly developed models of neurofiberscopes with a small outer diameter can be effectively used even in patients without ventriculomegaly. We present the case of a successful neurofiberscopic biopsy of a third ventricle anaplastic astrocytoma in a previously shunted patient without hydrocephalus. Subsequent gamma knife radiosurgery led to complete disappearance of the tumor. It seems that presence of collapsed ventricles, and even symptoms consistent with the slit ventricle syndrome, should not be considered as contraindications for neurofiberscopic surgery when brain compliance is sufficiently preserved. The latter should be considered as the key point of safe endoscopic manipulations. The combination of the neuroendoscopy and stereotactic radiosurgery provides wide possibilities for minimally invasive management of selected intracranial tumors.

Adolescent↗
PubMed2004

Evaluation of the ARMD1 locus on 1q25-31 in patients with age-related maculopathy: genetic variation in laminin genes and in exon 104 of HEMICENTIN-1.

The age-related maculopathy (ARM) genetics program at Columbia University utilizes comprehensive genetic analysis of candidate genes in large case-control studies to determine genotypes associated with the ARM complex trait. Genes encoding laminins, a class of extracellular matrix proteins, represent attractive candidates for two reasons. First, the presence of laminins in the basal lamina of the retinal pigment epithelium (RPE), Bruch's membrane, and choriocapillaris suggests a possible role in the pathophysiology of ARM. Second, three laminin genes, LAMC1, LAMC2, and LAMB3, are located in the 1q25-31 region, within the previously mapped ARMD1 locus. The entire open reading frame of the three laminin genes was screened for variants by denaturing high-performance liquid chromatography (DHPLC) and direct sequencing in at least 92, and up to 368 ARM patients and matched unaffected controls. Sixty-nine sequence variants were detected in the 69 exons of the LAMC1, LAMC2, and LAMB3 genes. Screening of exon 104 of the recently proposed ARMD1 gene, HEMICENTIN-1, residing in the 1q25-31 locus, did not detect the suggested causal variant, Q5345R, in 632 study subjects. Overall, we did not find statistically significant differences in the frequency of variants between ARM-affected individuals and age-matched controls. Four rare, non-synonymous, variants were detected in single cases of ARM patients. Our data on relatively limited numbers of study subjects do not suggest a significant role for genetic variation in the three laminin genes and in exon 104 of HEMICENTIN-1 in predisposing individuals to ARM. However, as in many instances in similar studies, involvement of rare amino acid-changing variants in a fraction of ARM cannot be ruled out.

Aged↗
PubMed2004

Marinospirillum insulare sp. nov., a novel halophilic helical bacterium isolated from kusaya gravy.

A novel species that belongs to the genus Marinospirillum is described on the basis of phenotypic characteristics, phylogenetic analysis of 16S rRNA and gyrB gene sequences and DNA-DNA hybridization. Four strains of helical, halophilic, Gram-negative, heterotrophic bacteria were isolated from kusaya gravy, which is fermented brine that is used for the production of traditional dried fish in the Izu Islands of Japan. All of the new isolates were motile by means of bipolar tuft flagella, of small cell size, coccoid-body-forming and aerophilic; it was concluded that they belong to the same bacterial species, based on DNA-DNA hybridization values (>70% DNA relatedness). DNA G+C contents of the new strains were 42-43 mol% and they had isoprenoid quinone Q-8 as the major component. Phylogenetic analysis of 16S rRNA gene sequences indicated that the new isolates were members of the genus Marinospirillum; sequence similarity of the new isolates to Marinospirillum minutulum, Marinospirillum megaterium and Marinospirillum alkaliphilum was 98.5, 98.2 and 95.2%, respectively. Phylogenetic analysis based on the gyrB gene indicated that the new isolates had enough phylogenetic distance from M. minutulum and M. megaterium to be regarded as different species, with 84.7 and 78.7% sequence similarity, respectively. DNA-DNA hybridization showed that the new isolates had <36% DNA relatedness to M. minutulum and M. megaterium, supporting the phylogenetic conclusion. Thus, a novel species is proposed: Marinospirillum insulare sp. nov. (type strain, KT=LMG 21802T=NBRC 100033T).

Animals↗
PubMed2004

Different clinicopathological courses of two recipients of kidneys retrieved from the same non-heart beating donor.

We report the clinicopathological courses of two recipients of kidneys retrieved from the same non-heart beating donor (NHBD). A 52-year-old man received a renal transplant from an NHBD. The donor was a 66-year-old woman who died of subarachnoid haemorrhage. The recipient was immunosuppressed by basiliximab, tacrolimus (TAC), mycophenolate mofetil (MMF), methyl prednisolone (MP), and antilymphocyte globulin (ALG). On post-operative day (POD) 21, haemodialysis therapy was withdrawn, however, their serum creatinine (s-Cr) level failed to improve. Four transplant biopsies were performed (1 h and POD 46, 74, and 114). The biopsy showed tubular degeneration but no evidence of TAC nephrotoxicity. The last biopsy after discontinuation of TAC demonstrated acute rejection of borderline grade. The s-Cr level at discharge was 5.0 mg/dL. The contra-lateral kidney was transplanted into a 31-year-old female and showed early functioning, with an s-Cr level at discharge of 1.8 mg/dL. Biopsy examination on POD 38 showed a recovery of tubular degeneration. The causes of delayed graft function and persistently high level of s-Cr in Case 1 remain unclear. Various factors, including donor-related factors, recipient-related factors, TAC nephrotoxicity, acute rejection, and urinary tract infection could all be associated with this condition.

Adult↗
PubMed2004

Deep cutting injury from the edges of a snowboard.

A laceration deep enough to reach the bone occurs very rarely in skiing or snowboarding. Two such cases are presented here. In one case, the popliteal fossa of a skier was cut during a collision with a snowboarder. All structures posterior to the knee were severed and the leg became ischaemic. The other case was of a snowboarder who sustained a deep cut to the distal forearm during landing after a jump, resulting in a "spaghetti wrist".

Adult↗
PubMed2004

A liver micronucleus assay using young rats exposed to diethylnitrosamine: methodological establishment and evaluation.

We have developed a simple liver micronucleus assay using young rats (up to 4 weeks old) to assess cytogenetic damage of chemicals in liver cells. Diethylnitrosamine (DEN) was used as a model rodent hepatocarcinogen in this study. Compared to the partial hepatectomy method most commonly used for the liver micronucleus assay, the present assay method showed equal or even higher practicability. The young rat liver micronucleus assay was also characterized for rat strain differences, sampling time after treatment, single treatment vs. split treatment, age of animals, administration route, and staining method. Although based on one model chemical, we propose an acceptable protocol for the micronucleus assay using young rat liver as follows: Up to 4-week-old rats should be used; oral or intraperitoneal administration can be used; single or repeated treatment protocols can be applied; sampling time is 3-5 days after the last treatment; hepatocytes are prepared by the collagenase perfusion method; and cells are stained with the AO-DAPI double staining method.

Acridine Orange↗
PubMed2004

Glomerular expression of biglycan and decorin and urinary levels of decorin in primary glomerular disease.

AIMS: Recent studies have suggested that small leucine-rich proteoglycans (SLRP) of the extracellular matrix play a major role in modulating the activity of growth factors and in regulating the deposition of collagens. In this study, the expression of the SLRPs biglycan and decorin in the glomeruli of patients with primary glomerular disease (minimal change disease, IgA nephropathy, and membranous nephropathy) and urine immunoreactive levels examined. METHODS: Renal biopsy specimens were obtained from patients with minimal change disease, IgA nephropathy and membranous nephropathy. Immunohistochemical staining was performed on fresh-frozen samples using anti-biglycan and anti-decorin antibodies. Examination of urine proteoglycan excretion from a total of 26 patients and 8 normal volunteers was performed by indirect ELISA. RESULTS: In normal kidney samples, biglycan and decorin expression was found predominantly in the intrarenal arteries and tubulointerstitium, with only minimal expression in the glomeruli. Glomerular expression of these proteoglycans in glomerular disease was unchanged in all of the 4 patients examined with minimal change disease. In the case of IgA nephropathy or membranous nephropathy, some of the patients showed minimally increased immunostaining of either biglycan or decorin, but there were no signs of simultaneous upregulation of both proteoglycans. To further examine the changes in proteoglycan expression, ELISA was performed on urine samples. Urine biglycan levels were below detection levels, but high values of urine decorin immunoreactivity were found in the patients with glomerular disease. A significant negative correlation was found between urine decorin and creatinine clearance. CONCLUSION: These results suggest that distinct changes in the expression of the SLRPs biglycan and decorin may be seen in patients with primary glomerular disease. Moreover, the negative relationship between urine decorin levels and renal function supports the hypothesis that decorin may be involved in the pathophysiology of renal dysfunction in humans.

Adult↗
PubMed2004

[Negative pleural cytology after intrapleural perfusion hyperthermo-chemotherapy for malignant pleural effusion].

We gave intrapleural perfusion hyperthermo-chemotherapy to a 72-year-old woman in whom malignant pleural effusion developed after surgery for primary cancer. This procedure involved irrigating the pleural space for 2 hours with a water solution at 42-43 degrees containing 240 mg cisplatin using specially devised extracorporeal circuits. Thoracoscopy was used to examine the intrapleural cavity and to place the catheters for perfusion. The patient had an uneventful postoperative course and was discharged for hospital on the second postoperative day. Thereafter, she experienced good quality of life with negative pleural cytology. Unfortunately, the patient died 3 months after the therapy, but the cause of death was unknown and there was no cancer recurrence. This technique may be safe and feasible for controlling malignant effusion to preserve quality of life, although the survival benefit has not yet been clarified.

Aged↗
PubMed2004

Injury of the lacrimal component of the nervus intermedius function after radiosurgery versus microsurgery.

RATIONALE: Due to the synergetic role of the facial nerve and the nervus intermedius in the mechanical protection of the eye, vestibular schwannomas (VS) and/or their treatment are dangerous for the visual function. Our goal was to evaluate and compare the impact of the tumor itself, and the microsurgery (MS) or radiosurgery (RS). MATERIAL AND METHOD: A functional questionnaire evaluating among other items the patient's complaints related to the eye was addressed to a series of 100 patients, 3 years after GKS of a previously unresected unilateral VS. Answers were compared with those of a group of 100 patients operated microsurgically. A Shirmer test was additionally performed before radiosurgery, and more than 2 years after radiosurgery in 46 patients. RESULTS: The risk of dry eye and burning eye was much higher in patients operated by MS compared to patients operated by GKS due to the high incidence of facial palsy in the former (57/99) and the its absence in the later (0/80). In the population operated microsurgically, the presence of a permanent facial palsy (57 patients among 99 responding to the questionnaire) was, of course, associated with a high rate of complaints about burning eye (n=18) and crying eye (n=23). Among patients from the two arms with no facial palsy, a dry eye was reported by 8/64 after GKS and 7/42 after MS (NS) and a burning eye by 9/64 after GKS and 9/42 after MS (NS). Thus patients with no clinical signs of impairement of the VII motor nerve accounted for 14% of the cases signs indicating injury of the intermedius nerve with the same probability whatever the kind of surgery. When no permanent facial palsy was observed a crocodile tear syndrome was more frequently observed after MS (4/42 versus 1/64, p=0.07). This suggests an early lesion of the VII motor and intermedius, and a subsequent abnormal regrowth. The only patient reporting a crocodile tear syndrome after GKS turned out to have presented transiently a discret deficit of orbicular muscle signaling transient partial facial nerve injury. In absence of facial palsy, a "crying eye" was reported more frequently after MS (16/42 versus 9/64, p=0.01), leading us to suspect frequent infraclinical VII nerve injury in patients with no obvious facial palsy operated by MS. Patients tested with Shirmer test, before and more than 2 Years after, were improved in 28.3%, stable in 56.5%, and worse in 15.2%. CONCLUSIONS: This study is the first demonstrating that radiosurgery can induce nervus intermedius injury in a small percentage of cases (14%). These patients had been treated 11 years ago with what we can consider as "archeoGKS technology" compared to today's refinements. The impact of modern GKS on the nervus intermedius is currently under evaluation in our group. However, symptoms related to the eye either due to the injury of the nervus intermedius or of the VII motor or both are much more frequent after MS than after RS.

Adolescent↗
PubMed2003

ATP-dependent regulation of SK4/IK1-like currents in rat submandibular acinar cells: possible role of cAMP-dependent protein kinase.

SK4/IK1 encodes an intermediate conductance, Ca2+ -activated K+ channel and fulfills a variety of physiological functions in excitable and nonexcitable cells. Although recent studies have provided evidence for the presence of SK4/IK1 channels in salivary acinar cells, the regulatory mechanisms and the physiological function of the channel remain unknown in these cells. Using molecular and electrophysiological techniques, we examined whether cytosolic ATP-dependent regulation of native SK4/IK1-like channel activity would involve endogenous cAMP-dependent protein kinase (PKA) in rat submandibular acinar (RSA) cells. Electrophysiological properties of tetraethylammonium (TEA) (10 mM)-insensitive, Ca2+ -dependent K+ currents in macropatches excised from RSA cells matched those of whole cell currents recorded from human embryonic kidney-293 cells heterologously expressing rat SK4/IK1 (rSK4/IK1) cloned from RSA cells. In outside-out macropatches, activity of native SK4/IK1-like channels, defined as a charybdotoxin (100 nM)-blockable current in the presence of TEA (10 mM) in the bathing solution, ran down unless both ATP and Mg2+ were present in the pipette solution. The nonhydrolyzable ATP analog AMP-PNP failed to support the channel activity as ATP did. The addition of Rp-cAMPS (10 microM), a PKA inhibitor, to the pipette solution containing ATP/Mg2+ induced a rundown of the Ca2+ -dependent K+ currents. Inclusion of cAMP (1 mM) into the pipette solution (1 microM free Ca2+) containing ATP/Mg2+ caused a gradual increase in the currents, the effect being pronounced for the currents induced by 0.1 microM free Ca2+. Forskolin (1 microM), an adenylyl cyclase activator, also increased the currents induced by 0.1 microM free Ca2+. In inside-out macropatches, cytosolic ATP/Mg2+ increased both the maximum current (proportional to the maximum channel activity) and Ca2+ sensitivity of current activation. Collectively, these results suggest that ATP-dependent regulation of native SK4/IK1-like channels, at least in part, is mediated by endogenous PKA in RSA cells.

Adenosine Triphosphate↗
PubMed2003

A new index, the core erosion ratio, of compression-coated timed-release tablets predicts the bioavailability of acetaminophen.

Although compression-coated tablets are a commonly used timed-release drug delivery technology, their utility is often limited by poor bioavailability. To try to improve the bioavailability of these tablets, the effect of their core composition of compression-coated tablet on in vivo pharmacokinetics was investigated. First, the extent of mass reduction of cores in different compression-coated tablet core formulations was used to establish a new index, the core erosion ratio. The data show that adding excipients with high water solubility to the core results in a greater core erosion ratio. Next, to elucidate the effect of core erosion ratio on in vivo acetaminophen (AAP) release, three compression-coated tablet formulations with similar in vitro AAP release profiles but different core erosion ratios were administered to four fasted dogs. The time for first appearance (TFA) of AAP in plasma did not differ significantly among formulations, indicating that the in vivo lag time was the same for all formulations. In separate experiments, necroscopy revealed that 3h after oral administration, the tablets were located in the ileum and colon and that all three formulations had identical GI transit times. However, the area under the AAP plasma concentration-time curve was greater in dogs given formulations with larger core erosion ratios. These results suggest that a formulation with a large core erosion ratio can significantly increase in vivo drug release from compression-coated tablets, leading to increased drug absorption from the lower GI tract.

Acetaminophen↗
PubMed2003

A gene homologous to beta-type carbonic anhydrase is essential for the growth of Corynebacterium glutamicum under atmospheric conditions.

Carbonic anhydrase catalyzes the interconversion of CO(2) and bicarbonate. We focused on this enzyme in the amino acid-producing organism Corynebacterium glutamicum in order to assess the availability of bicarbonate for carboxylation reactions essential to growth and for those required for L-lysine overproduction. A whole-genome sequence revealed two genes encoding putative beta-type and gamma-type carbonic anhydrases in C. glutamicum. These genes encode polypeptides containing zinc ligands strictly conserved in each type of carbonic anhydrase and were designated bca and gca, respectively. Internal deletion of the chromosomal bca gene resulted in a phenotype showing severely reduced growth under atmospheric conditions (0.04% CO(2)) on both complete and minimal media. The growth defect of the Delta bca strain was restored under elevated CO(2) conditions (5% CO(2)). Introduction of the red alga Porphyridium purpureum carbonic anhydrase gene ( pca) could compensate for the bca deletion, allowing normal growth under an atmospheric level of CO(2). In contrast, the Delta gca strain behaved identically to the wild-type strain with respect to growth, irrespective of the CO(2) conditions. Attempts to increase the dosage of bca, gca, and pca in the defined L-lysine-producing strain C. glutamicum AHD-2 led to no discernable effects on growth and production. Northern blot analysis indicated that the bca transcript in strain AHD-2 and another L-lysine producer, C. glutamicum B-6, was present at a much higher level than in the wild-type strain, particularly during exponential growth phases. These results indicate that: (1) the bca product is essential to achieving normal growth under ordinary atmospheric conditions, and this effect is most likely due to the bca product's ability to maintain favorable intracellular bicarbonate/CO(2) levels, and (2) the expression of bca is induced during exponential growth phases and also in the case of L-lysine overproduction, both of which are conditions of higher bicarbonate demand.

Amino Acid Sequence↗
PubMed2003

Neuropathological analysis in spinal muscular atrophy type II.

We performed a neuropathological analysis, including in situ nick end labeling (ISEL) and immunohistochemistry, of two cases of clinicogenetically confirmed infantile spinal muscular atrophy (SMA) type II. Both cases showed severe reduction of the motor neurons and gliosis in the spinal cord and brain stem, although the occurrences of central chromatolysis and ballooned neurons were not frequent. Clark's and lateral thalamic nuclei, which are usually altered in SMA type I, were spared, whereas Betz cells in the precentral gyrus and large myelinated fibers in the lateral funiculus were reduced in number. Regarding apoptosis, only the younger case demonstrated a few ISEL-positive nuclei in the dorsal horn, with reduced Bcl-x expression level in the Purkinje cells. Unlike SMA type I, the expression of neurofilaments was not disturbed and the reduction in synaptophysin expression level in the anterior horn was mild. An oxidative stress-related product was deposited in atrophic motor neurons in the spinal cord, and neurons with nuclei immunoreactive for 8-hydroxy-2'-deoxyguanosine were found in the lateral thalamus. In contrast, the expression of glial glutamate transporters was not altered. These data suggest that oxidative stress and, to a lesser extent, apoptotic cell death, but not disturbed neurofilament metabolism or excitotoxicity, may be involved in neurodegeneration in SMA type II.

Adult↗
PubMed2003

Vegetables and fruit intake and cancer mortality in the Hiroshima/Nagasaki Life Span Study.

The association between green-yellow vegetables and fruit consumption and risk of cancer death was investigated in a prospective study of 38 540 men and women who were atomic-bomb survivors in Hiroshima and Nagasaki, Japan. Study participants completed a dietary questionnaire in 1980-1981 and were followed-up for cancer deaths until March 1998, during which time 3136 cancer deaths were identified. Daily or almost daily fruit consumption was associated with a significant 12% reduction in total cancer mortality (RR=0.88; 95% CI, 0.80-0.96 for daily intake compared with intake once per week or less). Daily or almost daily green-yellow vegetables consumption was associated with a marginally significant 8% reduction in total cancer mortality (0.92; 0.94-1.01). Green-yellow vegetables consumption was associated with a significant reduction in liver cancer mortality (0.75; 0.60-0.95). Fruit consumption was associated with a significantly reduced risk of stomach cancer and lung cancer mortality (0.80; 0.65-0.98). Green-yellow vegetables and fruit consumption was associated with a reduction in oesophageal cancer, but these associations were not statistically significant. Neither green-yellow vegetables nor fruit consumption was associated with colorectal cancer or breast cancer mortality. These results support the evidence that daily consumption of fruit and vegetables reduces the risk of total cancer, and specifically cancers of the stomach, liver, and lung.

Cohort Studies↗
PubMed2003

Efficient 40 degrees C fermentation of L-lysine by a new Corynebacterium glutamicum mutant developed by genome breeding.

We have recently developed a new L-lysine-producing mutant of Corynebacterium glutamicum by "genome breeding" consisting of characterization and reconstitution of a mutation set essential for high-level production. The strain AHP-3 was examined for L-lysine fermentation on glucose at temperatures above 35 degrees C, at which no examples of efficient L-lysine production have been reported for this organism. We found that the strain had inherited the thermotolerance that the original coryneform bacteria was endowed with, and thereby grew and produced L-lysine efficiently up to 41 degrees C. A final titer of 85 g/l after only 28 h was achieved at temperatures around 40 degrees C, indicating the superior performance of the strain developed by genome breeding. When compared with the traditional 30 degrees C fermentation, the 40 degrees C fermentation allowed an increase in yield of about 20% with a concomitant decrease in final growth level, suggesting a significant transition of carbon flux distribution in glucose metabolism. DNA array analysis of metabolic changes between the 30 degrees C and 40 degrees C fermentations identified several differentially expressed genes in central carbon metabolism although we could not find stringent control-like global induction of amino-acid-biosynthetic genes in the 40 degrees C fermentation. Among these changes, two candidates were picked out as the potential causes of the increased production at 40 degrees C; decreased expression of the citrate synthase gene gltA and increased expression of malE, the product of which involves regeneration of pyruvate and NADPH.

Corynebacterium↗