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Biomedical subjects

Y Nitta

Publications and source records attributed to Y Nitta.

At least 127 records · Page 7Linked to original sources
PubMed1991

[A case of smoldering ATLL in high risk family and familial double infection of HTLV-1 and HBV].

A 35-year-old male from Kagoshima prefecture developed nodules with asymptomatic erythema on both upper eyelids, both hands and upper right leg in April 1986. On April 10, 1987, biopsy of skin lesions revealed numerous atypical CD4 positive lymphocytes which had invaded the dermis around the vessels. Analysis of serum showed positive antibody titer (X40) against the human T lymphotropic virus type I (HTLV-I) with some flower cells evident in peripheral blood; however, no infiltration into bone marrow or lymph nodes could be seen. Lymphocytes from peripheral blood and from the skin lesion of the right leg showed monoclonal integration of HTLV-I proviral DNA. Chronic active hepatitis B virus (HBV) was also a complicating factor. Familial study revealed all three family members to be infected with HTLV-1 as well as HBV. Proviral integration of HTLV-I was the intermediate type in two out of the three. From the results, a diagnosis of smoldering adult T cell leukemia-lymphoma (ATLL) was made in this patient with high risk to family members. Herein we discuss the development of ATLL in this case and infection among family members.

Adult↗
PubMed1990

Synthesis of O-alpha-D-glucopyranosyl-(1----4)-O-alpha -D-xylopyranosyl-(1----4)-O-alpha -D-xylopyranosyl-(1----4)-D-glucopyranose as a substrate analogue of alpha amylase.

The tetrasaccharide a-D-Glcp-(1----4)-a-D-Xylp-(1----4)-a-D-Xylp-(1----4)-D- Glcp (1) has been synthesized, as a substrate analogue of alpha amylase, by silver perchlorate-catalyzed glycosylation of benzyl 2,3,6-tri-O-benzyl-4-O-(2,3-di-O-benzyl-a-D-xylopyranosyl)-beta-D- glucopyranoside (30) with 2,3-di-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-a-D- glucopyranosyl)-a-D-xylopyranosyl chloride or by methyl triflate-promoted condensation of 30 with methyl 2,3-di-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-a-D-glucopyranosyl)-1-thio- beta-D-xylopyranoside, followed by removal of protecting groups of the resulting tetrasaccharide derivative 40.

Carbohydrate Sequence↗
PubMed1990

Microscopic incipient hepatocellular carcinoma found incidentally in a routine liver biopsy specimen.

A microscopic atypical focus suggestive of hepatocellular carcinoma is reported. The lesion, 0.3 mm in diameter, was found by chance in a liver biopsy specimen taken from a cirrhotic patient; it was characterized histologically by cytoplasmic basophilia, hypercellularity (high nucleus-to-cell ratio) and microacinar structures. The reticulin framework of the focus was relatively sparse compared with the surrounding noncancerous area. The focus had developed in a regenerative nodule apparently no different from other regenerative nodules of the cirrhosis and showed no accompanying preneoplastic lesion such as adenomatous hyperplasia. A thorough search for the primary lesion, including ultrasonographic imaging and superselective hepatic arteriography, demonstrated no mass lesion in the liver. Therefore, the lesion may have been an incipient de novo hepatocellular carcinoma, and this may be the first report of such a lesion discovered in a biopsy sample.

Adult↗
PubMed1990

[Washout rate in patients with hypertrophic cardiomyopathy and hypertensive cardiac hypertrophy].

The present study was performed to clinically clarify the pathogenesis of hypertensive cardiac hypertrophy (HT) and hypertrophic cardiomyopathy (HCM). Exercise thallium-201 (Tl-201) myocardial scintigraphy using a bicycle ergometer was performed for controls, HT and HCM. The scintigrams were evaluated by the circumferential profile analysis. Furthermore, the changes in Tl-201 dynamics in exercise Tl-201 scintigraphy with verapamil injections were examined in these three groups. Analysis of exercise Tl-201 scintigraphy without verapamil injections showed that the initial uptake did not differ among the three groups, but the washout rate three hours after the Tl-201 injections (WR3) did differ among the three groups. Although the WR3 of HT did not differ from that of the controls, the WR3 of HCM was lower than that of the controls. The WR3 with and without verapamil were compared. Although the WR with verapamil injections equalled that without verapamil injections in the controls and HT, the WR3 with verapamil injections decreased more than did that without verapamil injections in HCM. As an index of great and rapid changes in circulation, the washout rate one hour after the Tl-201 injection (WR1) was calculated. The WR1 without verapamil did not differ among the three groups and did not differ from that with verapamil injections in each group. These results suggest that Tl-201 dynamics of HT differ from those of HCM and lowering of the WR3 in HCM may not be caused by disturbance in the microcirculation, but rather by disturbance of Tl-clearance through the cell membrane and its cytoplasm.

Cardiomegaly↗
PubMed1989

Identification of glutamic acid 186 affinity-labeled by 2,3-epoxypropyl alpha-D-glucopyranoside in soybean beta-amylase.

Soybean beta-amylase was modified with 2,3-epoxypropyl alpha-D-[U-14C]glucopyranoside ([14C]alpha-EPG), a radioactive affinity-labeling reagent for beta-amylase, until it lost 95% of its enzyme activity. After S-carboxymethylation at pH 8.0 of SH groups, the modified enzyme was digested at pH 7.0 with Achromobacter protease I and the digest was fractionated by reverse-phase HPLC. A radioactive peptide was finally isolated and its amino acid sequence was determined to be 181Leu-Gly-Pro-Ala-Gly-Glu186. Radioactivity derived from [14C]-alpha-EPG was found exclusively at Glu-186, the gamma-carboxyl group of which is esterified with the affinity label. It was concluded that the carboxylate of Glu-186 is a functional group at the catalytic site of soybean beta-amylase.

Affinity Labels↗
PubMed1989

Neonatal lupus syndrome and microtubular structure.

A female infant, at 6 weeks old, with the clinical manifestation of annular erythemas on the trunk and face, was positive for anti-SS-A and anti-SS-B antibodies. The annular erythema disappeared spontaneously at the age of 7 months when anti-SS-A and anti-SS-B antibodies were negative. Electron microscopic observation of the vascular endothelial cells on the annular erythema revealed microtubular structures. Later microtubular structures were found absent from the vascular endothelial cells of the area where the annular erythema had disappeared. The patient's mother is suffering from Sjögren's syndrome; she has no clinical symptoms but anti-SS-A and anti-SS-B antibodies are positive and a biopsy of small salivary glands of the lip demonstrated a marked periductal mononuclear cell infiltration. Microtubular structures were observed in her vascular endothelial cells in the small salivary gland region. These findings suggest that disappearance of microtubular structure may have some relationship with anti-SS-A and anti-SS-B antibodies.

Antibodies, Antinuclear↗
PubMed1989

Unstable expression of E-cadherin adhesion molecules in metastatic ovarian tumor cells.

E-Cadherin is a member of the cadherin family, which plays a key role in intercellular adhesion in various tumors as well as in normal tissues. Here, we examined the expression of this adhesion molecule in a murine ovarian tumor line OV2944, whose sublines show different degrees of spontaneous metastasis from subcutaneous sites; sublines LM-1 and LM-3 exhibit a low metastatic activity but a variant subline HM-1 has a high metastatic activity. When the expression of E-cadherin in these cells was examined by immunoblot analysis, the highly metastatic HM-1 cells was found to express an extremely small amount of this molecule, as compared with a high level of E-cadherin expression in the weakly metastatic LM-1 and LM-3 cells. Northern blot analysis showed that the amount of tanscripts from the E-cadherin gene is proportional to the amount of proteins detected in these cells. Immunofluorescence staining revealed that cells of the highly metastatic line were heterogeneous, that is, their cultures contained both E-cadherin-positive and negative cells. In contrast, cells of the weakly metastatic lines homogeneously expressed E-cadherin. When the highly metastatic line was subcloned, all the subclones consisted of E-cadherin-positive and negative cells. These results suggest that the expression of E-cadherin gene is not stably controlled in the highly metastatic line.

Animals↗
PubMed1989

[Clinical trial of T-3262 on acute enteritis. Japan Research Committee of T-3262, Research Group for Acute Infectious Enteritis].

For the purpose of evaluation of clinical efficacy, safety and usefulness on acute infectious enteritis (bacillary dysentery, and enteritis caused by Salmonella spp., Campylobacter spp., enteropathogenic E. coli, and so on), T-3262, a newly developed pyridone-carboxylic acid derivative, was administered to a total of 136 patients and carriers. In addition, in vitro antibacterial activity of T-3262 was determined against the clinical isolates, and compared with those of nalidixic acid (NA), pipemidic acid (PPA), enoxacin (ENX), norfloxacin (NFLX) and ofloxacin (OFLX). The daily dose of 450 mg of T-3262 was administered orally three times after meals for 5 days, with the exception of 7 day administration against Salmonella enteritis. A total of 89 cases were evaluated; 23 with Shigella spp., 30 with Salmonella spp., 15 with Campylobacter spp., 6 with enteropathogenic E. coli, and 15 cases with the other pathogens or pathogen-negative. The efficacy on clinical symptoms judging from duration of fever, and duration of diarrhea and abnormal stool character was 100% in all the enteritis except enteropathogenic E. coli enteritis, in which it was 50% (n = 2). Concerning bacteriological response, elimination of the causative organisms from the feces was 100% in Shigella spp. (n = 19), Salmonella spp. (n = 30), and enteropathogenic E. coli (n = 6), although 64.3% in Campylobacter spp. (n = 14). As an adverse effect, epigastric discomfort was observed in one (0.8%) of 130 cases. Deteriorations in laboratory findings were seen in five (6.2%) of 81 cases, consisting of two with elevated GOT and GPT, two with elevated GPT, and one with increased eosinophils count, although they were all slight in degree. MICs of T-3262 which inhibited 90% of the isolates of Shigella spp, Salmonella spp., and Campylobacter spp., were 0.025, 0.05, and 0.78 microgram/ml, respectively. These values were lowest among the quinolone derivatives tested, except that the MIC90 against Campylobacter spp. was the same as that of ofloxacin.

4-Quinolones↗
PubMed1989

[Comparison of clinical efficacy of lomefloxacin (LFLX, NY-198) and pipemidic acid (PPA) in the treatment of infectious enteritis by a double-blind method. The Japan Research Committee of Lomefloxacin Research Group Enteritis].

The clinical efficacy, safety and usefulness of lomefloxacin (LFLX, NY-198), a new quinolone antimicrobial agent, were compared with those of pipemidic acid (PPA) in the treatment of infectious enteritis (bacillary dysentery, enteropathogenic Escherichia coli enteritis and Campylobacter enteritis) by a double blind method. Daily dosage of LFLX and PPA was 600 mg and 2000 mg, respectively administered orally divided into 4 doses. The duration of the treatment was 5 days. Of 290 cases studied, 100 cases were excluded and 21 cases were dropped from analysis of effectiveness and usefulness. The effectiveness and usefulness was evaluated in 169 cases (LFLX group: 83, PPA group: 86). There was no significance difference between the two groups in any background characteristics. The results obtained were as follows: 1. In 73 symptomatic patients (LFLX group: 35, PPA group: 38) on the day of the beginning of administration, the clinical effect was 91.4% in the LFLX group and 84.2% in the PPA group with no significant difference between the two groups. 2. In a total of 184 strains (LFLX group: 90, PPA group: 94), the bacteriological effects of LFLX (93.3%) was superior to that of PPA (80.9%) with significant difference (p = 0.0153). 3. In 169 evaluable patients, the global clinical effects of LFLX (92.8%) was superior to that of PPA (79.1%) with a significant difference (P = 0.0144). 4. Side effects were observed in 1 (0.7%) of the 141 patients in the LFLX group and none of the 143 patients in the PPA group. Abnormal laboratory test values were noted in 10 (7.6%) of the 132 patients treated with FLLX and 7 (5.1%) of the 136 patients treated with PPA, but they as no significant difference between the two groups. 5. In 169 evaluable patients, the clinical usefulness of LFLX (91.6%) was superior to that of PPA (76.7%) with a significant difference (P = 0.0111). From these results, LFLX is considered to be a clinically useful medicine in the treatment of infectious enteritis including bacillary dysentery.

4-Quinolones↗
PubMed1989

[Several properties of a newly developed light-cured anterior restorative composite resin "Graft LC"].

A newly developed light-cured anterior restorative composite resin "Graft LC" by GC Co. is characterized by having Vita VMK 68 shades and containing glass filler particles treated with graft binders. Several properties of the resin were examined by using the SEM, surface recorder, and color analyzer. The Graft LC resin was classified as semi-hybrid resin. The filler particles of Graft LC resin comprised two kinds of glass filler in which Si, Ba and Al, and Si were detected. Graft LC resin showed a relatively small surface roughness after polishing in spite of the semi-hybrid resin. According to the degradation test in the alkaline solution, the polished surfaces of Graft LC resin became rough and the depth of subsurface damage layer increased with time. However, the filler particles were retained in the subsurface damage layers. An Ar ion etching employed for SEM preparation is useful to observe the subsurface damage layer distinctly under the SEM. No color change was found even after long-term immersion in a distilled water, though the color of Graft LC resin changed greatly due to irradiation.

Biodegradation, Environmental↗
PubMed1987

Energetics of alpha-chymotrypsin-mediated hydrolysis of a strained cyclic ester.

Hydrolysis of omicron-hydroxy-alpha-toluenesulfonic acid sultone (sultone II) is mediated by alpha-chymotrypsin. Sultone II is a highly strained cyclic ester substrate that forms a covalent intermediate with the enzyme and is therefore expected to release ring-strain energy upon formation of the sulfonyl enzyme species. It is found that the equilibrium constant for forming the covalent intermediate from the Michaelis complex is quite modest (K2 = 16.4), suggesting that perhaps the strain energy is not released in the ring-cleavage event. The implied retention of chemical (strain) energy by the sulfonyl enzyme species raises the question of the means by which the enzyme avoids expression of strain energy and the implications of this effect in the catalytic sequence. High-pressure liquid chromatography (HPLC) rate data demonstrate facile reversion of sulfonyl enzyme to the Michaelis complex, and that reversion is preferred over hydrolysis of the covalent intermediate. pH-independent rate and equilibrium constants are derived for the alpha-chymotrypsin-mediated hydrolysis of sultone II, and pKa values for groups on the enzyme are reported that are consistent with literature values obtained from analysis of nonspecific substrate hydrolysis by the enzyme.

Animals↗
PubMed1986

Affinity labeling of soybean beta-amylase with 2',3'-epoxypropyl alpha-D-glucopyranoside.

The synthesized 2',3'-epoxypropyl alpha-D-glucopyranoside (alpha-EPG) inactivated soybean beta-amylase completely. The incorporation of alpha-EPG into the enzyme at 92% inactivation was 1.1 mol per mol of enzyme, as determined by using 14C-labeled alpha-EPG. The inactivation obeyed saturation kinetics of a two-step mechanism. The dissociation constant of alpha-EPG-enzyme complex and the rate constant of the irreversible inactivation step were estimated to be 119 mM and 1.14 X 10(-3)s-1, respectively. alpha-Cyclodextrin, a competitive inhibitor of this enzyme, protected the enzyme against the inactivation by alpha-EPG in a competitive manner. This suggests that alpha-EPG binds to the active site of the enzyme. The above results indicate that alpha-EPG acts on soybean beta-amylase as an affinity labeling reagent. It was also shown that an essential SH group near the active site, but not the catalytic one, scarcely participated in the inactivation by alpha-EPG.

Affinity Labels↗