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S Shinohara

Publications and source records attributed to S Shinohara.

At least 19 recordsLinked to original sources
PubMed2005

Replica multichannel polymer chips with a network of sacrificial channels sealed by adhesive printing method.

Replica microchips for capillary array electrophoresis containing 10 separation channels (50 microm width, 50 microm depth and 100 microm pitch) and a network of sacrificial channels (100 microm width and 50 microm depth) were successfully fabricated on a poly(methyl methacrylate) (PMMA) substrate by injection molding. The strategy involved development of moving mask deep X-ray lithography to fabricate an array of channels with inclined channel sidewalls. A slight inclination of channel sidewalls, which can not be fabricated by conventional deep X-ray lithography, is highly required to ensure the release of replicated polymer chips from a mold. Moreover, the sealing of molded PMMA multichannel chips with a PMMA cover film was achieved by a novel bonding technique involving adhesive printing and a network of sacrificial channels. An adhesive printing process enables us to precisely control the thickness of an adhesive layer, and a network of sacrificial channels makes it possible to remove air bubbles and an excess adhesive, which are crucial to achieving perfect sealing of replica PMMA chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to simultaneously monitor electrophoretic separations in ten micro-channels with laser-induced fluorescence detection. High-speed and high-throughput separations of a 100 bp DNA ladder and phi X174 Hae III DNA restriction fragments have been demonstrated using a 10-channel PMMA chip. The current work establishes the feasibility of mass production of PMMA multichannel chips at a cost-effective basis.

Adhesives↗
PubMed2004

Case report: internal and external jugular vein thrombosis with marked accumulation of FDG.

We report an unusual case of idiopathic internal and external jugular vein thrombosis. Positron emission tomography (PET) using (18)F-fluoro-2-deoxy-D-glucose (FDG), which was conducted to assess subclinical malignancy, revealed intense uptake of FDG, corresponding to thrombus within the left internal and external jugular veins. Although FDG-PET is widely used in differentiating between malignant and benign diseases, we should bear in mind that this benign entity can demonstrate high accumulation of FDG.

Fluorodeoxyglucose F18↗
PubMed2001

Implantation metastasis of head and neck cancer after fine needle aspiration biopsy.

One possible complication of the aspiration biopsy of malignant tumors is dissemination of tumor cells along the needle track. However, a search of the literature revealed few definite reports of implantation metastases of head and neck tumors after fine needle aspiration biopsy (FNAB). Here we report two cases of skin metastasis of head and neck cancer after FNAB, including a patient with papillary adenocarcinoma of the thyroid and one with adenoid cystic carcinoma of the submandibular gland. Surgical treatment prevented the spread of the tumor in both cases and there have been no evidence of recurrence to date. This report should alert head and neck surgeons to the possibility of implantation metastasis after FNAB.

Adenocarcinoma, Papillary↗
PubMed2001

[Evaluation of RI scintiscanning to parotid gland tumors].

We retrospectively evaluated preoperative radioisotope (RI) scintiscans in 275 patients (283 glands) with parotid tumors who undergoing surgery between 1987 and 2000. Technetium-99m-pertechnetate (Tc) scintigraphy was conducted on 201 glands. Oncocytoma and Warthin's tumor showed a high positive rate. In evaluating Warthin's tumor with Tc scintigraphy, sensitivity was 75% and specificity 88%; above the age of 40 years, specificity exceeded 90%. Gallium-67-citrate (Ga) scintigraphy was conducted on 207 glands. Malignant parotid tumors showed high positivity (85%), but the specificity of positive findings was quite low (38%) because 44% of benign pleomorphic adenoma, which occupied major material, showed Ga-positive findings. Ga-negative findings indicated high probability (95%) of benign tumors. Thus, Tc scintigraphy is effective in diagnosing Warthin's tumor, while Ga scintigraphy is effective in diagnosing benign tumors.

Adenolymphoma↗
PubMed2001

Regulation of cell proliferation using tissue engineering in MIN6 cells.

Pancreatic islet transplantation for patients with diabetes mellitus has been hindered by the problem of donor shortage, as is the case for transplantation of other organs. Among several measures to overcome this problem, cell transplantation using xenogenic cell lines has been considered. For the treatment of diabetic patients, a murine pancreatic beta-cell line MIN6 is a potential source of cell transplant. In order to restrict otherwise unlimited proliferation of transplanted MIN6 cells, cells are rendered to form spheroidal aggregates (SMIN6) on nonadherent culture dishes. SMIN6 stopped its growth around day 7 with a diameter of 220 +/- 40 microm and kept its size almost constant at least until day 28. SMIN6 cells, however, had reduced responsiveness of insulin secretion to glucose concentration compared with MIN6 cells cultured in a monolayer. On the other hand, spheroid MIN6 cells formed in the presence of extracellular matrix gel (SMIN6E) possessed the capacity for glucose-dependent insulin secretion comparable with conventional MIN6 cells. SMIN6E encapsulated in agarose beads (SMIN6E-B) was also viable for at least 1 month in vitro with a constant diameter and favorable glucose responsiveness. The development of spheroid-type MIN6 may contribute to the future clinical application of MIN6 or other beta-cell lines for treatment of diabetes mellitus.

Animals↗
PubMed2000

Clinical features of sudden hearing loss associated with a high signal in the labyrinth on unenhanced T1-weighted magnetic resonance imaging.

We report on five patients with high signals in the labyrinth on unenhanced magnetic resonance imaging who developed sudden hearing loss and vertigo. Weissman et al. (1992) suggested the possibility that such high signals were caused by hemorrhage. We assessed these patients using audiograms, caloric tests, and auditory brainstem responses to investigate the possibility of inner ear hemorrhage. Most of the patients were found to have severe and irreversible impairment of both cochlear and vestibular function. These findings were consistent with the hypothesis that their symptoms were caused by inner ear hemorrhage.

Adolescent↗
PubMed2000

Isolation of Campylobacter species from zoo animals and polymerase chain reaction-based random amplified polymorphism DNA analysis.

A total of 104 fecal specimens from 30 mammals, 12 birds, and 3 reptiles at the Phoenix Zoological Gardens, Miyazaki City, Japan, were examined for the presence of Campylobacter species. All the animals examined were healthy with no fecal abnormality. Twenty-three (22.1%) thermophilic campylobacters, (9 C. jejuni, 11 C. hyointestinalis, 2 C. coli, and 1 C. lari), were isolated from 11 animals (7 mammals and 4 birds). C. jejuni and C. hyointestinalis were the predominant species isolated from these zoo animals and C. hyointestinalis was isolated frequently from simians. As selective media influence the numbers and species of campylobacters isolated, the agar medium was not supplemented with cephalothin. Campylobacters were isolated most frequently when a combination of enrichment culture and selective agar plating was performed at 42 degrees C. For the epidemiological study, a polymerase chain reaction (PCR)-based randomly amplified polymorphic DNA (RAPD) method was used as a tool to detect the heterogeneity of amplified DNAs of Campylobacter spp. isolated from zoo animals. The two arbitrary primers used in this study enabled even closely related strains of the same Campylobacter spp. to be differentiated. RAPD analysis revealed considerable diversity among the strains, suggesting that the transmission of Campylobacter spp. among animals in a defined area occurred through different mechanisms. Examination of the genotypic diversity among the multiple clones from the same host also revealed differences between clones. These results demonstrate that campylobacter populations in zoo animals are highly divergent.

Animals↗
PubMed2000

[A study of institutional medical care of female victims of sexual assault and violence].

OBJECTIVE: The purpose of the study is to clarify the present situation of medical care for victims of sexual assault and violence. Medical facilities in two wards in Tokyo were studied in order to know what problems regarding medical care exist and how to support female victims. METHODS: In April 1998, we distributed questionnaires to 338 medical facilities covering all the clinics and hospitals, that had more than only otorhinolaryngology and ophthalmology, in Kouto-ku and Sumida-ku, Tokyo. The questionnaire included questions about individual experience of consulting with sexual assault and violence against women, the number of victims in the last year, and their understandings for victims. RESULT: 1) 76 of the respondents completed the answer sheet by themselves. The mean age of the subjects was 57.4 years old, 16.3% of them had seen sexual assault victims, and about 36.8% had cared for victims of violence. 2) 67 victims of sexual assault and violence were reported in the previous year. 36% of victims of sexual assault were reported by facilities related to obstetrics, and 85% of victims of violence were reported by general medical facilities. 3) As for understandings for victims, those who thought the victims were responsible for the sexual assault also regarded violence as caused by carelessness of victims. CONCLUSION: Medical facilities may be an important place to care for victims of sexual assault and violence against women. There are few data available as to how many women suffer from sexual violence. This study showed for the first time the reality of sexual assault and violence from the viewpoints of medical facilities in Japan, although it had some limitations. It is necessary for more discussion about roles of medical care for female victims of sexual assault and violence.

Adolescent↗
PubMed1999

Electrocochleographic documentation of temporal findings of speech perception in normal and hearing-impaired individuals.

Compound action potentials (CAPs) evoked by the short Japanese syllables /a/ and /ka/ were recorded by extratympanic electrocochleography in 17 subjects with normal hearing (17 ears) and 34 patients with sensorineural hearing losses (35 ears) to investigate the temporal aspects of speech coding for perception. In normal ears, three characteristics were found common to the temporal patterns of all CAPs: (1) a prominent CAP at the beginning of both stimuli; (2) periodic CAPs with the same interval as the pitch period through the vowel part of both stimuli; (3) absence of a prominent CAP at the onset of voice. These characteristics may help to produce consonant recognition. Among the subjects with sensorineural hearing loss, some ears showed the following two characteristics different from those with normal hearing: (1) a significantly lower CAP at the onset of both stimuli than in those with normal hearing; (2) decay of CAPs during the voiced part. These findings may result in abnormal loudness perception in sensorineural hearing loss as produced by loudness recruitment and pathological adaptation. Such different temporal patterns of CAPs may have an adverse influence on the speech discrimination of patients with sensorineural hearing impairments.

Acoustic Stimulation↗
PubMed1999

Genetic and biochemical characterization of a 2-pyrone-4, 6-dicarboxylic acid hydrolase involved in the protocatechuate 4, 5-cleavage pathway of Sphingomonas paucimobilis SYK-6.

Sphingomonas paucimobilis SYK-6 is able to grow on a wide variety of dimeric lignin compounds with guaiacyl moieties, which are converted into protocatechuate by the actions of lignin degradation enzymes in this strain. Protocatechuate is a key metabolite in the SYK-6 degradation of lignin compounds with guaiacyl moieties, and it is thought that it degrades to pyruvate and oxaloacetate via the protocatechuate 4,5-cleavage pathway. In a 10.5-kb EcoRI fragment carrying the protocatechuate 4,5-dioxygenase gene (ligAB) (Y. Noda, S. Nishikawa, K. Shiozuka, H. Kadokura, H. Nakajima, K. Yoda, Y. Katayama, N. Morohoshi, T. Haraguchi, and M. Yamasaki. J. Bacteriol. 172:2704-2709, 1990), we found the ligI gene encoding 2-pyrone-4, 6-dicarboxylic acid (PDC) hydrolase. PDC hydrolase is a member of this pathway and catalyzes the interconversion between PDC and 4-carboxy-2-hydroxymuconic acid (CHM). The ligI gene is thought to be transcribed divergently from ligAB and consists of an 879-bp open reading frame encoding a polypeptide with a molecular mass of 32,737 Da. The ligI gene product (LigI), expressed in Escherichia coli, was purified to near-homogeneity and was estimated to be a monomer (31.6 kDa) by gel filtration chromatography. The isoelectric point was determined to be 4.9. The optimum pH for hydrolysis of PDC is 8.5, the optimum pH for synthesis of PDC is 6.0 to 7.5, and the Km values for PDC and CHM are 74 and 49 microM, respectively. LigI activity was inhibited by the addition of thiol reagents, suggesting that the cysteine residue is a catalytic site. LigI is more resistant to metal ion inhibition than the PDC hydrolases of Pseudomonas ochraceae (K. Maruyama, J. Biochem. 93:557-565, 1983) and Comamonas testosteroni (P. J. Kersten, S. Dagley, J. W. Whittaker, D. M. Arciero, and J. D. Lipscomb, J. Bacteriol. 152:1154-1162, 1982). The insertional inactivation of the ligI gene in S. paucimobilis SYK-6 led to the complete loss of PDC hydrolase activity and to a growth defect on vanillic acid; it did not affect growth on syringic acid. These results indicate that the ligI gene is essential for the growth of SYK-6 on vanillic acid but is not responsible for the growth of SYK-6 on syringic acid.

Carboxylic Ester Hydrolases↗
PubMed1999

Antimicrobial activity and metalloprotease inhibition of hinokitiol-related compounds, the constituents of Thujopsis dolabrata S. and Z. hondai MAK.

Gamma-thujaplicin, beta-dolabrin and hinokitiol(beta-thujaplicin), hinokitiol-related compounds isolated from the wood of Thujopsis dolabrata S. and Z. hondai MAK have antimicrobial activity. In particular, strong antibacterial activity of hinokitiol and beta-dolabrin on Staphylococcus epidermidis IFO-12993 was found, with a minimum inhibitory concentration (MIC) of 0.2 microg/ml. This activity was higher than that of gentamicin, used as a positive control, and so the strong antibacterial activity of both compounds on this bacterium is of considerable interest. Of the three compounds, gamma-thujaplicin showed the strongest antifungal activity and its MIC was found to be around 1.5 microg/ml. The three compounds also inhibited metalloproteases. The inhibitory activity of hinokitiol on carboxypeptidase A was especially strong, its 50%-inhibitory concentration (IC50) being 2.76x10(-6) M. Considering that metalloproteases are involved in inflammation, the strong inhibitory activity of hinokitiol could be important. On the other hand, hinokitiol-acetate did not show any antimicrobial activity and metalloprotease inhibition, suggesting that at least part of the activity is due to metal chelation between the carbonyl group at C-1 and the hydroxyl group at C-2 in the tropolone skeleton.

Anti-Bacterial Agents↗
PubMed1998

Diversity of myocardial involvement in systemic sclerosis: an 8-year study of 95 Japanese patients.

BACKGROUND: Myocardial fibrosis has been reported to be an important complication of systemic sclerosis (SSc). Left ventricular (LV) hypertrophy has also been reported, but its significance is unclear. Correlations between cardiac complications and clinical or serologic subsets of SSc have not been previously evaluated by long-term observational studies. METHODS: We correlated the findings of echocardiography, electrocardiography, and autopsy with clinical and serologic features in 95 patients with SSc who were monitored for up to 8 years. RESULTS: Septal thickness determined by echocardiography was significantly greater in patients with anti-nuclear ribonucleoprotein (nRNP) antibodies than in patients with anti-Scl70 or anticentromere antibodies. Fractional shortening was reduced in patients with diffuse cutaneous involvement or anti-Scl70 antibodies. Ten patients had cor pulmonale, which was confirmed by echocardiography. Four of them had diffuse cutaneous involvement and advanced pulmonary fibrosis, whereas four had anti-nRNP antibodies and mild or no fibrosis. Septal hypertrophy was detected in 12 patients, 10 of whom had limited cutaneous involvement and six had anti-nRNP antibodies. Diffuse or regional LV wall hypokinesia was seen in seven patients, of whom six had anti-Scl70 antibodies and five had diffuse cutaneous involvement. Six patients with cor pulmonale, five with abnormal LV wall motion, and three with septal hypertrophy died during the follow-up period. Autopsy revealed LV hypertrophy in three with septal hypertrophy, disarray and irregular hypertrophy of myocytes in one of them, and extensive myocardial fibrosis in one with diffuse LV wall hypokinesia. CONCLUSIONS: Septal hypertrophy and cor pulmonale caused by pulmonary vasculopathy were associated with limited cutaneous involvement or anti-nRNP antibodies, whereas abnormal LV wall motion and cor pulmonale caused by advanced pulmonary fibrosis were mostly seen in patients with diffuse cutaneous involvement or anti-Scl70 antibodies.

Adult↗
PubMed1998

Prognosis of accidental low back pain at work.

Accidental low back pain at the workplace was classified into two groups; 177 cases of the organic type and 176 cases of the non-specific type. Concerning the recuperation period, the length of leave, and the amount of compensation for recuperation, medical cost and leave of absence, a comparison was made between two groups. Regarding age, sex, and the type of work, no difference was found between the organic and the non-specific groups. However, the non-specific group showed lower values than the organic one for the duration of recuperation and leave and the amount of compensation for medical cost and leave of absence. Multiple regression analysis showed that the difference in the type of low back pain had more influence on the duration and cost than that in sex and age. The prognosis of non-specific low back pain is better than that of organic one in terms of cost and duration.

Accidents, Occupational↗
PubMed1997

Isolation and identification of hematopoietic stem cell-stimulating substances from Kampo (Japanese herbal) medicine, Juzen-taiho-to.

We have previously found that TJ-48 has the capacity to accelerate recovery from hematopoietic injury induced by radiation and the anti-cancer drug mitomycin C (MMC). The effects are found to be due to its stimulation of spleen colony-forming unit (CFU-S) counts on day 14. In the present study, we attempt to isolate and purify the active components in TJ-48 extracts using a new in vitro hematopoietic stem cell (HSC) assay method. n-Hexane extract from TJ-48 shows a significant stimulatory activity. The extract is further fractionated by silica gel chromatography and HPLC in order to identify its active components. 1H-NMR and GC-EI-MS indicate that the active fraction is composed of free fatty acids (oleic acid and linolenic acid). When 27 kinds of free fatty acids (commercially available) are tested using the HSC proliferating assay, oleic acid, elaidic acid, and linolenic acid are found to have potent activity. The administration of oleic acid to MMC-treated mice enhances CFU-S counts on days 8 and 14 to twice the control group. These findings strongly suggest that fatty acids contained in TJ-48 actively promote the proliferation of HSCs. Although many mechanisms seem to be involved in the stimulation of HSC proliferation, we speculate that at least one of the signals is mediated by stromal cells, rather than any direct interaction with the HSCs.

Animals↗
PubMed1997

Electrophysiological changes in rat hippocampal pyramidal neurons produced by cholecystokinin octapeptide.

Effects of cholecystokinin octapeptide (CCK-8) were investigated in CA1 pyramidal neurons of rat hippocampal slice cultures using the whole-cell patch-clamp technique. In the current-clamp mode, CCK-8 (100 nM) produced slight depolarizaton (2.1 +/- 0.3 mV) and reduced the amplitude of afterhyperpolarization following a train of spikes. CCK-8 (10 nM-1 microM) concentration-dependently reduced the amplitude of afterhyperpolarization. CCK-4, a selective agonist for CCK(B) receptors, also attenuated the amplitude of afterhyperpolarization. CCK-8-induced suppression was completely abolished by (+)L-365,260, a selective CCK(B) receptor antagonist, but not by (-)L-364,718, a selective CCK(A) receptor antagonist. Similarly, CCK-8 reduced the tail currents following a depolarizing pulse. The tail currents were characterized as Ca2+-activated K+ currents. When neurons were held at a holding potential of -40 mV, CCK-8 elicited inward currents with a reduction of membrane conductance. This current had a relatively linear current voltage relationship and was reversed in polarity at membrane potentials close to the K+ equilibrium potential, suggesting that CCK-8 decreases leak K+ currents. Moreover, voltage-activated Ca2+ currents were partially blocked by CCK-8, and this effect was enhanced by intracellular application of GTPgammaS (300 microM) or a protein phosphatase inhibitor, okadaic acid (100 nM), and attenuated by GDPbetaS (300 microM) or a protein kinase inhibitor, staurosporin (400 nM). In acutely-prepared hippocampal slices from neonatal rats, CCK-8 also depolarized CA1 pyramidal neurons and suppressed afterhyperpolarization following a train of action potentials. These results indicate that CCK-8 increases neuronal excitability by suppressing leak K+ currents and Ca2+-activated K+ currents in CA1 pyramidal neurons of the hippocampus through activation of CCK(B) receptors.

Animals↗
PubMed1997

Amyloid beta protein potentiates Ca2+ influx through L-type voltage-sensitive Ca2+ channels: a possible involvement of free radicals.

Amyloid beta protein (A beta), the central constituent of senile plaques in Alzheimer's disease (AD) brain, is known to exert toxic effects on cultured neurons. The role of the voltage-sensitive Ca2+ channel (VSCC) in beta (25-35) neurotoxicity was examined using rat cultured cortical and hippocampal neurons. When L-type VSCCs were blocked by application of nimodipine, beta (25-35) neurotoxicity was attenuated, whereas application of omega-conotoxin GVIA (omega-CgTX-GVIA) or omega-agatoxin IVA (omega-Aga-IVA), the blocker for N- or P/Q-type VSCCs, had no effects. Whole-cell patch-clamp studies indicated that the Ca2+ current density of beta (25-35)-treated neurons is about twofold higher than that of control neurons. Also, beta (25-35) increased Ca2+ uptake, which was sensitive to nimodipine. The 2', 7'-dichlorofluorescin diacetate assay showed the ability of beta (25-35) to produce reactive oxygen species. Nimodipine had no effect on the level of free radicals. In contrast, vitamin E, a radical scavenger, reduced the level of free radicals, neurotoxicity, and Ca2+ uptake. These results suggest that beta (25-35) generates free radicals, which in turn, increase Ca2+ influx via the L-type VSCC, thereby inducing neurotoxicity.

Amyloid beta-Peptides↗
PubMed1997

Adverse effects of colophony.

Regarding colophony, the use in industries, adverse effects, diagnosis, pathophysiology and control are reviewed. Colophony is an unhomogeneous mixture of resin acids as like abietic acid and neutral substances. Colophony is used everywhere, in industry, daily life and medical supplies. Soldering workers are exposed to the colophony fumes heated up to the temperature of soldering irons. The effects of exposure to colophony are classified into bronchial asthma and contact dermatitis. Colophony fumes cause bronchial asthma by its nonspecific irritation. Inhalation challenge test and repeated spirometry during working day may help the diagnosis of colophony induced asthma. Improvement of working environment for soldering and development of new flux instead of colophony will be necessary. A study on contact dermatitis revealed that colophony and its related compounds are one of major causes for contact dermatitis. Cases of dermatitis by depilatory agents used to remove hair from slaughtered swine, anti-slipping cream for ballet shoes or resin for cello strings have been reported. Patch test may contribute to the diagnosis of dermatitis caused by colophony.

Asthma↗