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Biomedical subjects

H Nakano

Publications and source records attributed to H Nakano.

At least 235 records · Page 13Linked to original sources
PubMed2000

Transfructosylation of thiol group by beta-fructofuranosidases.

Beta-fructofuranosidase fructosylated not only the hydroxyl group but also the thiol group of 2-mercaptoethanol in a transfer reaction using sucrose as a donor substrate. The enzymes from Candida utilis and Saccharomyces cerevisiae (bakers' yeast) were effective catalysts for the thio-fructofuranosylation. The thio-fructosylation product was isolated by activated carbon chromatography and its structure was confirmed by Fab-mass spectrometry and NMR spectroscopy. The thio-fructofuranoside was synthesized effectively at around 3.0 M for the acceptor concentration. The product increased with the sucrose concentration at least up to 1.9 M. O-Fructofuranoside was simultaneously synthesized at an early stage of the reaction, although it was hydrolyzed on further incubation. On the contrary, the thio-fructofuranoside accumulated efficiently after synthesis, indicating it was very stable against the hydrolytic action of the beta-fructofranosidase.

Carbohydrate Conformation↗
PubMed2000

Hydrolysis of beta-galactosyl ester linkage by beta-galactosidases.

p-Hydroxybenzoyl beta-galactose (pHB-Gal) was synthesized chemically to examine the hydrolytic activity of beta-galactosyl ester linkage by beta-galactosidases. The enzyme from Penicillium multicolor hydrolyzed the substrate as fast as p-nitrophenyl beta-galactoside (pNP-Gal), a usual substrate with a beta-galactosidic linkage. The enzymes from Escherichia coli and Aspergillus oryzae hydrolyzed pHB-Gal with almost the same rates as pNP-Gal. The enzymes from Bacillus circulans, Saccharomyces fragilis, and bovine liver showed much lower activities. pH-activity profiles, inhibition analysis, and kinetic properties of the enzymic reaction on pHB-Gal suggested that beta-galactosidase had only one active site for hydrolysis of both galactosyl ester and galactoside. The Penicillium enzyme hydrolyzed pHB-Gal in the presence of H218O to liberate galactose containing 18O. This result suggests the degradation occurs between the anomeric carbon and an adjacent O atom in the ester linkage of pHB-Gal.

Animals↗
PubMed2000

Synthesis of novel heterobranched beta-cyclodextrins from alpha-D-mannosylmaltotriose and beta-cyclodextrin by the reverse action of pullulanase, and isolation and characterization of the products.

Alpha-D-mannosyl-maltotriose (Man-G3) were synthesized from methyl alpha-mannoside and maltotriose by the transfer action of alpha-mannosidase. (Man-G3)-betaCD and (Man-G3)2-betaCD were produced in about 20% and 4% yield, respectively when Aerobacter aerogenes pullulanase (160 units per 1 g of Man-G3) was incubated with the mixture of 1.6 M Man-G3 and 0.16 M betaCD at 50 degrees C for 4 days. The reaction products, (Man-G3)-betaCD were separated to three peaks by HPLC analysis on a YMC-PACK A-323-3 column and (Man-G3)2-betaCD were separated to several peaks by HPLC analysis on a Daisopak ODS column. The major product of (Man-G3)-betaCDs was identified as 6-O-alpha-(6(3)-O-alpha-D-mannosylmaltotriosyl)-betaCD by FAB-MS and NMR spectroscopies. The structures of (Man-G3)2-betaCDs were analyzed by TOF-MS and NMR spectroscopies, and confirmed by comparison of elution profiles of their hydrolyzates by alpha-mannosidase and glucoamylase on a graphitized carbon column with those of the authentic di-glucosyl-betaCDs. The structures of three main components of (Man-G3)2-betaCDs were identified as 6(1),6(2)-, 6(1),6(3)- and 6(1),64-di-O-(63-O-alpha-D-mannosyl-maltotriosyl)-betaCD.

Cyclodextrins↗
PubMed2000

Purification and some properties of a beta-glucosidase from Flavobacterium johnsonae.

Flavobacterium johnsonae was isolated as a microorganism that produced a beta-glucosidase with hydrolytic activity of beta-glucosyl ester linkages in steviol glycosides. The enzyme was purified to homogeneity from a cell-free extract by streptomycin treatment, ammonium sulfate fractionation, and column chromatographies on S-Sepharose and phenyl-Toyopearl. The molecular mass of the purified enzyme was about 72 kDa by SDS-PAGE. An isoelectric point of pI 8.8 was estimated by isoelectric focusing. The enzyme was most active at pH 7.0, and was stable between pH 3.0 and 9.0. The optimum temperature was 45 degrees C, and the enzyme was stable below 35 degrees C. The enzyme hydrolyzed glucosyl ester linkages at site 19 of rebaudioside A, stevioside, and rubusoside, although it could not degrad beta-glucosidic linkages at site 13 of rebaudioside B or steviol bioside. The enzyme acted on aryl beta-glucosides such as p-nitrophenyl beta-glucoside, phenyl betaglucoside, and salicin, and glucobioses such as sophorose and laminaribiose. The enzyme activity on Rub was inactivated completely by Hg2+, and reduced by Fe3+, Cu2+, p-chloromercuric benzoate, and phenylmethylsulfonyl fluoride (residual activity; 67.9-84.8%). The pNPG hydrolysis was also inactivated to almost the same degrees. Kinetic behaviors in the mixed substrate reactions of rebaudioside A and steviol monoside, and of steviol monoglucosyl ester and phenyl beta-glucoside suggested the glucosidic and glucosyl ester linkages were hydrolyzed at a single active site of the enzyme.

Chromatography, High Pressure Liquid↗
PubMed2000

Galactosylation of thiol group by beta-galactosidase.

beta-Galactosidase catalyzed beta-galactosylation not only of a hydroxyl group but also of a thiol group in the condensation reaction of D-galactose and 2-mercaptoethanol. The thio-galactosylation product was confirmed as 2-hydroxyethyl S-beta-D-galactoside on the bases of fast atom bombardment mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectorometry. Aspergillus oryzae beta-galactosidase hydrolyzed p-nitrophenyl S-beta-D-galactoside most rapidly among several beta-galactosidases and produced the thio-galactosylation product most efficiently. The Penicillim multicolor enzyme was as effective as the A. oryzae enzyme. However the enzymes from Escherichia coli, Saccharomyces fragilis, Kluyveromyces lactis, and Bacillus circulans galactosylated hydroxyl groups predominantly to produce O-galactoside. The thio-galactoside was synthesized most effectively at a 2-mercaptoethanol concentration of about 1.25 M. Galactose concentration at 0.8-2.8 M did not affect the synthetic yield of the thiogalactoside so greatly.

Aspergillus oryzae↗
PubMed2000

Two cases of acute myositis associated with influenza A virus infection in the elderly.

During the influenza epidemic of 1998-1999, we observed two elderly patients with influenza-like symptoms who had evidence of acute myositis with elevated serum enzymes. Influenza A infection was confirmed serologically in either case. The present cases suggest that it is important to distinguish influenzal myositis from other forms of myopathy in the elderly patients.

Acute Disease↗
PubMed2000

The significance of interleukin-6 concentrations in cervicovaginal fluid: its relation to umbilical cord plasma and the influence of antibiotic treatment.

This study was performed to correlate cervicovaginal fluid and umbilical cord plasma level of IL-6 and IL-8 in patients with premature rupture of the membranes (PROM) and to see the effect of antibiotics on those concentrations. As a part of a randomized controlled trial of treatment in PROM with antibiotics, cervicovaginal fluid was sampled before delivery for measurement of IL-6 and IL-8 and for bacteria from 36 patients less than 36 weeks of gestation. Umbilical cord plasma was also collected. Concentrations of IL-6 and IL-8 were measured by an ELISA. Neonatal infections were noted in a total of 9 cases, including bacteria detection (Escherichia coli 2 cases, GBS and Streptococcus constellata) in 4 cases. Correlation between IL-6 in cervicovaginal fluid and in cord plasma (r = 0.881, p < 0.0001) was stronger than that of IL-8 (r = 0.469, p < 0.01). The difference of concentrations in IL-6 and IL-8 was not significant between cases with (n = 20) and without (n = 16) ampicillin. Our observation indicates that the measurement of IL-6 concentrations in cervicovaginal fluid is a useful marker for PROM patients who are more likely to develop neonatal infection and the antibiotic treatment does not necessarily produce their beneficial effects on fetuses at the risk of infection.

Anti-Bacterial Agents↗
PubMed2000

A case report of sinonasal teratocarcinosarcoma.

A sinonasal teratocarcinosarcoma (SNTCS) is a rare and aggressive malignant neoplasm histologically characterized by the combination of one or more epithelial elements and mesenchymal components. We report a case of a 78-year-old man with SNTCS involving the nasal cavity and paranasal sinuses. He complained of epiphora and exophthalmos with weight loss. Physical and diagnostic images resulted T4N0M0. The tumor was completely and widely resected via a trans-facial approach to perform total maxillectomy with orbital exenteration. The clinical presentation, pathologic features, and clinical course are described with a review of the literature.

Aged↗
PubMed2000

Pulmonary lymphangiomyomatosis (LAM) developing chylothorax.

We describe a case of pulmonary lymphangiomyomatosis (LAM) with chylothorax that developed in a 46-year-old Japanese woman. This patient exhibited clinical symptoms of dyspnea and chest X-ray showed right pleural effusion. Thoracocentesis demonstrated chylous effusion. Chest computed tomography (CT) scan revealed multiple cystic lesions. Subsequent thoracoscopy revealed the chylorrhea from swelled vessels on the diaphragm. The clinical diagnosis, based on histological examinations with biopsy specimens obtained by thoracoscopy, was pulmonary LAM. Although the hormone therapy was not effective, chylous effusion was improved by the pleurodesis. Pulmonary LAM developing chylothorax is rare in Japan.

Chylothorax↗
PubMed2000

Calcification of the cervical ligamentum flavum--case report.

A 52-year-old male presented with calcification of the cervical ligamentum flavum manifesting as hypesthesia of the bilateral middle, ring, and little fingers and ulnar halves of both forearms, as well as motor weakness in the bilateral upper extremities and gait disturbance. Cervical x-ray tomography detected a round calcified mass on the posterior wall of the cervical canal at the C-5 level. Computed tomography showed the round, nodular calcified mass more clearly. Magnetic resonance imaging showed an epidural low intensity mass compressing and distorting the cervical cord at the C-5 level on both T1- and T2-weighted images. Administration of gadolinium-diethylenetriaminepenta-acetic acid caused marginal enhancement of the mass. The lesion was eventually removed by posterior laminectomy. The mass was composed of a very hard crystal-like calcified deposition in the ligamentum flavum. X-ray diffraction analysis of the histological specimen showed calcium pyrophosphate dihydrate (CPPD) and hydroxyapatite in the crystal-like substance, confirming that CPPD is responsible for calcification of the cervical ligamentum flavum.

Calcinosis↗
PubMed2000

Report of three cases of Alzheimer's disease with focal motor symptoms: clinical correlates of neuroimaging findings.

We report clinical and neuroimaging findings for three patients suffering from Alzheimer's disease (AD) with focal motor symptoms. These patients initially showed cognitive deficits and subsequently featured myoclonus and awkward movements in the unilateral upper limb while progressing to paresis. Paresis was noted in the unilateral upper limb. All patients held the unilateral arm flexed at the wrist and elbow, closely adducted to the body and the hand fisted and pronated. No signs of cerebellar ataxia, sensory disturbance or long tract signs were observed, nor any of the initial non-cognitive behavioural changes typical of frontotemporal dementia. EEGs of these patients showed marked slowing of basic activity without epileptic discharges. MRIs showed progressive brain atrophy in the contralateral frontoparietal lobes as well as the hippocampal formation. Cases 2 and 3 featured extensive long T2 lesions on MRI. 99mTc-HMPAO-SPECT revealed blood flow hypoperfusion in the corresponding regions. The cerebellum and brain stem showed neither morphological abnormalities nor blood flow hypoperfusion. On the basis of these clinical and neuroimaging observations, the focal motor symptoms were attributed to contralateral frontoparietal cortical atrophy with or without white matter lesion.

Aged↗
PubMed2000

[Automated infant auditory screening using the Natus-ALGO 2e in the NICU].

Natus-ALGO 2e, an automated ABR screener(Natus Medical, Foster City, CA, USA), compares the V wave of ABR evoked by 35-dB-nHL click stimuli by using a template-matching detection algorithm that provides only a pass-refer outcome. The aim of this study was to compare Natus-ALGO 2e with conventional ABR, and to evaluate its usefulness. The Natus-ALGO 2e screener was used to screen 202 ears of 101 neonates in our neonatal intensive care unit. The mean conceptional age at the time of screening was 40.4 +/- 3.0 weeks. 60 ears of 30 infants at high-risk of hearing impairment, including "refer" infants, were tested by the Natus-ALGO 2e and conventional ABR methods, and the results were compared. All neonates were tested with the Natus-ALGO 2e screener in a state of natural sleep, and screening time averaged 2 minutes 58 seconds. There were 97 cases in which both ears were passed, 3 cases in which both ears were referred, and one case in which one ear was referred. In comparison with conventional ABR, 53 of the 60 ears of 30 high-risk infants passed by the Natus-ALGO 2e method, whereas 14 of the 53 ears initially failed the conventional ABR screening. Of these 14 ears disagreements (the results of the Natus-ALGO 2e method passed, but the results of the conventional ABR failed), the results of the ABR screening changed to normal in 11 ears, and ABR showed improved threshold and latency in the other 3 ears after 5 weeks to 12 months. Among those that passed the Natus-ALGO 2e screening, the number of sweeps that failed the ABR screen was significantly greater than with normal ABR. Of the 7 ears of 4 patients that were referred on the basis of the Natus-ALGO 2e screening and failed by the conventional ABR method, 3 ears screened by the ABR method were normal when retested, and one ear passed by the Natus-ALGO 2e screening 12 weeks to 11 months later. In conclusion, Natus-ALGO 2e is useful for screening infant hearing because it can be performed quickly while the patient is sleeping naturally. In infants at high-risk for hearing impairment, the results of Natus-ALGO 2e and conventional ABR screening conflicted in numerous sweeps. Therefore, when there are many sweeps in high-risk infants, a retest should be performed that includes conventional ABR, even if they passed with Natus-ALGO 2e.

Audiometry, Evoked Response↗
PubMed2000

Effect of intrathecal nocistatin on the formalin-induced pain in mice versus that of nociceptin/orphanin FQ.

The effect of intrathecal nocistatin on formalin-induced pain in mice was investigated and compared with that of nociceptin/orphanin FQ (Noc/OFQ) to get information on the functional relationship between nocistatin and Noc/OFQ in the spinal cord. Subcutaneous injection of formalin into the hindpaw induced biphasic pain behaviors. Nocistatin, 1 pg, given intrathecally 1 min before 2% formalin injection, significantly attenuated the first phase of the formalin-induced pain. Also, 10 to 1000 pg of nocistatin, given 10 min after formalin injection, significantly inhibited the second phase of the formalin test. Naloxone, 5 mg/kg i.p., failed to antagonize inhibitory effects of nocistatin on either phase of the formalin-induced pain, indicating that analgesic effects of nocistatin were unrelated to the classic opioid system. At 1 to 100 pg, Noc/OFQ exerted no influence on either phase of the 2% formalin-induced pain. However, at 1% formalin, Noc/OFQ significantly aggravated the second phase at 10 pg but not the first phase at 1 to 1000 pg. This aggravating effect of Noc/OFQ was completely reversed by 10 pg of nocistatin. At 0.3 and 1 microg, Noc/OFQ, but not nocistatin, significantly inhibited both phases of the 2% formalin-induced pain. Suppressive effects of 1 microg of Noc/OFQ on the formalin-induced pain were not affected by 1 microg of nocistatin. These results suggest that Noc/OFQ might be involved in the second phase of the mouse formalin test and that, under such pathophysiological conditions, nocistatin could exhibit antagonism against Noc/OFQ at the spinal level.

Animals↗
PubMed2000

[A case report: Carpentier-Edwards porcine bioprosthesis malfunction due to the stent dehiscence at 17 years after the implantation in the mitral position].

A 53-year-old female had undergone mitral valve replacement with Carpentier-Edwards (C-E) porcine bioprosthesis for mitral valve regurgitation at the other hospital in November, 1981. Postoperative clinical course was uneventful, since she was referred from the other hospital in 1990. In December, 1997, she had sudden complaint of shortness of breath on effort, and the chest X-ray showed pulmonary congestion and increase of cardio-thoracic ratio. Echocardiography and catheterization revealed severe mitral regurgitation due to bioprosthesis malfunction and aortic valve regurgitation. Combined mitral and aortic valve replacement was successfully performed with mechanical valves in February, 1998. The explanted C-E porcine bioprosthesis showed the commissural dehiscence from only one of the three stents without any leaflet perforation, commissural tear, pannus overgrowth, impaired leaflet mobility and leaflet deterioration or calcification. This case suggested the variety of malfunction of C-E porcine bioprosthesis and the limitation of its long-term durability.

Aortic Valve↗
PubMed2000

[A case of advanced gastric cancer with hepatic metastasis successfully treated by combined chemotherapy with UFT and lentinan].

We have experienced successful treatment of a hepatic metastasis of gastric cancer with UFT and lentinan. The patient was a 65-year-old male, who underwent distal gastrectomy for gastric cancer with hepatic and lymphatic metastases. After operation, administrations of UFT 300 mg/day and lentinan 2 mg/2 weeks were given, and the hepatic metastasis disappeared by 17 months. We performed a resection of the residual stomach and lymphatic metastasis at 52 months after operation. For over 5 years the patient has shown no evidence of a recurrence of the hepatic metastasis. This chemotherapy regimen was very effective and improved the patients quality of life.

Adenocarcinoma↗