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N Yuasa

Publications and source records attributed to N Yuasa.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Double filtration plasmapheresis (DFPP) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)].

We studied the therapeutic characteristics of double filtration plasmapheresis (DFPP) in 14 patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). The patients were classified into 2 subgroups of the responders (7 patients) and the non-responders (7 patients) to DFPP. The responders to DFPP were designated as those showing the improvement 2 or more grades in measures the activity of daily living by the modified Rankin scale (MRS). All these patients underwent neurological assessment, CSF study, electrophysiological studies at the beginning and end of treatment. Sural nerve biopsy study was performed in 10 cases. Neurological function was assessed serially using a quantitative neurological disability score (NDS). At the beginning of treatment, there were no significant differences in various measurements between the responders and the non-responders except for the frequency of demyelination. In responders, significant improvement was found in mean changes in MRS, NDS, motor nerve conduction velocity, compound muscle action potential, distal motor latency, while in non-responders, all measures remained unchanged or worsened. Muscle wasting was seen in 3/7 responders and 4/7 non-responders, and denervation potentials in needle EMG were seen in 1/7 responders and 3/7 non-responders. Four patients of the responders were classified as chronic relapsing course, and 6 patients of the non-responders as chronic progressive course. We conclude that DFPP was useful for the subgroups of CIDP patients, but the underlying immuno-pathological background that determine the efficacy of plasmapheresis should be elucidated.

Activities of Daily Living↗
PubMed1996

Detection of species specific epitopes of mouse and hamster prion proteins (PrPs) by anti-peptide antibodies.

Antisera to four synthetic peptides containing the substitutions between mouse and hamster prion proteins (PrPs) were produced in rabbits. The synthetic peptides used represent two mouse (Mo-I: residues 100-115 and Mo-V: residues 199-208) and two hamster PrP subregion sequences (Ha-I: 101-116 and Ha-V: 200-209). All antisera reacted strongly with homologous peptides but either not at all or poorly with heterologous peptides in enzymelinked immunosorbent assay (ELISA). Antisera to Mo-I and Mo-V recognized mouse PrPSc but not hamster PrpSc in western blot analysis (WB) and ELISA. Antisera to Ha-I contain antibodies specific to hamster PrPSc. The results indicate that these regions of PrPSc constitute species-specific epitopes. In contrast to these antisera, the antiserum to Ha-V recognized neither hamster nor mouse PrPSc. In this study, we identified mouse subregion-V as a species-specific epitope.

Amino Acid Sequence↗
PubMed1996

Immunoreactivity of specific epitopes of PrPSc is enhanced by pretreatment in a hydrated autoclave.

An abnormal protein (PrPSc) accumulates in animals affected with scrapie. Immunoblotting procedures have been used widely to detect PrPSc. Blotted membranes were subjected to pretreatment in a hydrated autoclave, and the subsequent immunoreactivity of PrPSc was examined. The immunoreactivity of PrPSc to antisera against the synthetic peptides of the mouse PrP amino acid sequences 199 to 208 and 213 to 226 was enhanced by the pretreatment. However, the reactivity to antisera of peptide sequences 100 to 115 and 165 to 174 was not affected. The antibody-binding ability of the specific epitopes which are located close to the C-terminal end of PrP27-30 the proteinase-resistant portion of PrPSc, was enhanced by pretreatment in a hydrated autoclave. This pretreatment increased the sensitivity of PrPSc, and it would be useful for diagnosis of scrapie.

Animals↗
PubMed1995

Preparation and characterization of antibodies against mouse prion protein (PrP) peptides.

Antisera were raised in rabbits against three peptides, representing amino acid sequences 150 to 159, 165 to 174, and 213 to 226 of mouse prion (PrP), which were synthesized by using a multiple antigenic peptide (MAP) system. The reactivities of these sera to PrP were examined by an enzyme-linked immunosorbent assay (ELISA), Western immunoblotting (WB), and immunohistochemical procedures. The results of both ELISA and WB showed that antisera to peptide sequence 150 to 159 (Ab150-159) did not react with purified mouse PrP. On the other hand, sera to the sequence 165 to 174 (Ab165-174) reacted weakly with purified mouse PrP, as detected by WB but not by ELISA. However, antiserum to peptide sequence 213 to 226 (Ab213-226) reacted strongly with mouse, Syrian hamster, and sheep PrP by WB and with mouse PrP as shown by the results of ELISA. Moreover, Ab213-226 clearly detected PrP immunohistochemically in mouse, Syrian hamster, and sheep brains affected with scrapie as well as in the brain of a cow with bovine spongiform encephalopathy. From these data, we conclude that rabbit antiserum against the MAP representing amino acid sequence 213 to 226 of mouse PrP is useful as a diagnostic tool for prion disease of animals.

Amino Acid Sequence↗
PubMed1995

[Two cases of multiple liver metastases (H3) from colon cancer treated by home hepatic arterial infusion chemotherapy].

Two cases with unresectable multiple liver metastases to both lobes (H3) from colon cancer, in which cases the life expectancy usually does not exceed 1 year, were treated with home hepatic arterial infusion chemotherapy employing implantable port system. They could live over one year with good performance status. Drug treatment consisted of the administration of carboplatin (CBDCA), 150 mg/body, given in a minute for one day and 5-fluorouracil (5-FU), 250 mg/body, given in a 5-hour intra-arterial infusion daily for 5 days. Cycles were administered every 2 weeks. Home hepatic arterial infusion chemotherapy using an implantable port system, which offers good local control of liver metastases, a high patient quality of life without the need for hospitalization, is suitable for treatment of unresectable liver metastases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Angiographic changes in the hepatic artery after skeletonization resection for biliary tract cancer.

Using preoperative and postoperative arteriography, angiographic changes in the hepatic artery were studied after skeletonization of the hepatoduodenal ligament and hepatic resection for biliary tract carcinoma. Of 52 patients evaluated (32 with carcinoma of the bile duct, 20 with gallbladder cancer), no angiographic changes were apparent after operation in 30 (58 per cent) and there were pathological findings in 22 (42 per cent; smooth stenosis in five patients, irregular stenosis in seven, a beaded appearance in four, dilatation in two, obstruction in four). Based on angiographic findings, patients were classified into three subgroups (no change, 30 patients; irregular form, 18; obstructed, four). Postoperative liver function was also evaluated. No definite correlation was evident between angiographic findings and the incidence of hepatic failure or liver dysfunction in the first month after operation. Given that connective tissue and lymph node dissection in the hepatoduodenal ligament is essential for curative resection of biliary tract carcinoma, these findings suggest that skeletonization is an acceptable operative procedure.

Adolescent↗
PubMed1994

Sphincter of Oddi motility in patients with bile duct stones. A comparative study using percutaneous transhepatic manometry.

The motility of the sphincter of Oddi was measured by percutaneous transhepatic manometry of the sphincter of Oddi (PTMSO) in three groups of 57 patients with bile duct stones. The three groups were: (1) cholecystectomy group (N = 10)--patients with common bile duct stones (CBDS) who had already undergone cholecystectomy; (2) noncholecystectomy group (N = 37)--patients with CBDS who had not undergone cholecystectomy; and (3) intrahepatic stone (IHS) group (N = 10). The basal pressure, amplitude, frequency, and propagation direction of contraction waves and the response to cerulein injection or dried egg yolk ingestion were analyzed and compared among these groups. No significant differences in the basal pressure, amplitude, frequency, and propagation direction of the contraction waves were found among the three groups. There were also no differences in the response to cerulein or dried egg yolk ingestion. The frequency and duration of the burst contractions occurring in duodenal phase III of the migrating motor complex were significantly higher (P < 0.05) in the cholecystectomy group than in the other two groups. These two differences in the burst contractions may be ascribed to the absence of the gallbladder.

Adult↗
PubMed1993

A long term observation of antibody status to chicken anaemia virus in individual chickens of breeder flocks.

The antibody status to chicken anaemia virus (CAV) in four layer breeder flocks was evaluated. Sera were periodically collected from the same 17 to 20 individual chickens of each flock ranging in age from 10 to 63 weeks old. The neutralising and fluorescence antibody were detectable in individual chickens during the observation periods ranging from 13 to 44 weeks. A high prevalence of both neutralising and fluorescence antibodies was observed; however, the prevalence of fluorescence antibody in older chickens was lower than that of neutralising antibody. The geometric mean (GM) of neutralising antibody titres, after all the chickens examined had seroconverted in flocks 1, 2 and 4, ranged from 373.2 to 2940.6. In flock 1, the GM titre at 63 weeks old was significantly lower than that at 37 and 52 weeks old. In flock 4, the GM titre at 48 weeks old was significantly lower than that at 24 and 35 weeks old. In flock 2, the GM titre at more than 31 weeks old significantly increased compared with that at 25 weeks old; this tendency was not seen in the GM of the fluorescence antibody titres. The results indicate that immunity to CAV can last a long time in naturally infected individual chickens.

Animals↗
PubMed1993

Purification and partial characterization of the major outer membrane protein of Haemophilus somnus.

We purified the major outer membrane protein (MOMP), which is the most abundant OMP (with an apparent molecular mass of 40 kDa), from Haemophilus somnus strain 8025. The method involves solubilization of the MOMP with Zwittergent 3-14 and further purification accomplished by ion-exchange and molecular-sieve chromatographies. The amino-terminal sequence of the MOMP showed considerable similarity to those of porin proteins from other gram-negative bacteria. The MOMP of H. somnus is immunogenic to rabbits and calves. Hyperimmune sera from rabbits and calves reacted with both the MOMP and lipopolysaccharides in enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis. The rabbit antiserum to the MOMP was cross-reactive with whole-cell preparations from strains 8025, D1238, NT2301, and 540 at a band with a molecular mass of 40 kDa in immunoblot analysis, although the reactivity of the rabbit antiserum with strain 540 was lower than those with the other strains tested. Two murine monoclonal antibodies (MAbs) to the MOMP were developed. ELISA with the OMP fractions as the antigens showed that one MAb was cross-reactive with the four strains but that the other MAb was reactive with the three strains other than strain 540. These results indicate that the MOMP of H. somnus possesses at least two antigenic determinants and that the MOMP of strain 540 is antigenically different from those of the other strains. The antigenic heterogeneity of the H. somnus MOMP has implications regarding the development of a serotyping system with MAbs that is based on the MOMP epitopes.

Amino Acid Sequence↗
PubMed1993

Characterization of an immunoreactive 17.5-kilodalton outer membrane protein of Haemophilus somnus by using a monoclonal antibody.

A single outer membrane protein (OMP) of Haemophilus somnus, with an apparent molecular mass of 17.5 kDa, was identified in the sodium dodecyl sulfate (SDS)-insoluble fraction after extraction with 1% SDS-0.5 M NaCl-0.1% beta-mercaptoethanol. A hybridoma derived from mice immunized with H. somnus OMP fractions produced a monoclonal antibody (MAb), designated 20-3-5, that bound to the 17.5-kDa OMP of H. somnus. The MAb 20-3-5 epitope was present on 45 of 45 strains of H. somnus tested. MAb 20-3-5 cross-reacted with Haemophilus agni, Histophilus ovis, and Haemophilus haemoglobinophilus but not with 13 other species and subspecies of gram-negative bacteria. Immunoelectron-microscopic and antibody absorption studies revealed that the MAb 20-3-5 epitope is exposed on the surface of bacteria. In an immunoblot analysis, convalescent-phase sera obtained from calves with experimental H. somnus pneumonia contained antibodies to the 17.5-kDa OMP of H. somnus. Future studies will be directed toward examining the role of the 17.5-kDa OMP in immunity to H. somnus infections.

Animals↗
PubMed1993

Characterization of a heat-modifiable outer membrane protein of Haemophilus somnus.

In immunoblot analysis, a murine monoclonal antibody (MAb), 27-1, which was produced to an outer membrane protein (OMP) of Haemophilus somnus, showed that a major OMP is heat modifiable, having a molecular mass of 28 kDa when the N-lauroylsarcosine-insoluble OMP preparation was solubilized at 60 degrees C and a mass of 37 kDa when the OMP preparation was solubilized at 100 degrees C. The heat-modifiable OMP reacted intensely with convalescent sera obtained from calves with experimental H. somnus pneumonia in immunoblot analysis. Immunoelectron microscopic and antibody absorption studies revealed that the MAb 27-1 epitope was not surface exposed on the intact bacterium. However, a decrease in antibody reactivity to the heat-modifiable OMP in immunoblot analysis after absorption of convalescent serum with intact bacterial cells of H. somnus suggests that a surface-exposed portion of the heat-modifiable OMP is expressed on the intact bacterium. MAb 27-1 reacted with 45 of 45 strains of H. somnus tested in immunoblot analysis. The apparent molecular mass of the antigen varied among strains, and five reactivity patterns demonstrated by MAb 27-1 were observed. MAb 27-1 also reacted with six species in the family Pasteurellaceae, Escherichia coli, and Salmonella dublin, but not with the other eight species of gram-negative bacteria. The heat-modifiable OMP of H. somnus showed immunological cross-reactivity with the OmpA protein of E. coli K-12 and significant N-terminal amino acid sequence homology with the OmpA proteins of gram-negative bacteria. We conclude that a major, 37-kDa heat-modifiable OMP of H. somnus, which elicits an antibody response in H. somnus-infected animals, is a common antigen among H. somnus strains tested and is structurally related to the OmpA protein of E. coli.

Amino Acid Sequence↗
PubMed1993

Antigenic analysis of the major outer membrane protein of Haemophilus somnus with monoclonal antibodies.

The major outer membrane protein of Haemophilus somnus possesses at least five distinct epitopes. Three surface-exposed epitopes on the major outer membrane protein include a conserved epitope with potential for development of a vaccine and a diagnostic test and two variable epitopes responsible for antigenic differences among strains; the remaining two epitopes are well preserved among strains but not exposed on the cell surface.

Antibodies, Bacterial↗
PubMed1992

[Clinical study of 76 cases of smooth muscle tumor of the stomach].

Seventy six patients with smooth muscle tumor of the stomach (18 leiomyoma, 58 leiomyosarcoma) operated at Cancer Institute Hospital are presented. 1) Advanced age, short duration of illness, region of the middle portion of the stomach, large tumor size and ulcerative tumor were suggestive of pathological malignancy. 2) Male, symptomatic and larger tumor size were suggestive of poor prognosis. 3) The rate of curative surgery was 94.8% for fifty eight patients with leiomyosarcoma. The cumulative five-year survival rate after curative operation was 74.9% for all patients with leiomyosarcoma. Regardless of resecting method, all patients with tumors less than 5 cm in diameter lived without any indication of recurrence. 4) Four of the 58 patients with leiomyosarcoma had regional lymph node metastasis and died at less than 5 years following operation.

Adult↗
PubMed1988

Epitopic diversity of African swine fever virus.

African swine fever (ASF) is caused by an icosahedral cytoplasmic, double stranded DNA virus. In the acute form of the disease, pigs die from disseminated intravascular coagulation (DIC) with extensive damage of the free and fixed macrophage systems and the reticular epithelial cells of the thymus; mortality is virtually 100%. In recent years, subacute and chronic forms of ASF have become more prevalent in the field, especially in outbreaks occurring outside the continent of Africa, and virus isolated from these outbreaks have often been of lesser virulence. In pigs experimentally infected with such isolates, a number of immunopathological manifestations have been encountered, e.g. hypergammaglobulinemia associated with necrotizing pneumonia, persistent infection in the presence of ASF-specific antibodies, and lack of demonstrable virus neutralizing antibodies. Nevertheless, the immune systems of pigs that have clinically recovered have not been impaired by the infection. We suggest that the heterogeneous composition of the virus population in a given isolate may be one of the causes of the anomalous immune responses. When a number of biological markers, i.e., hemadsorption characteristics, plaque size, infectivity, virulence, antigenic determinants, and genomic structure, were used to characterize the virus clones derived from various ASF virus (ASFV) isolates, considerable heterogeneity was apparent. In the present investigation, 20 monoclonal antibodies (MAb), which specifically identified the 14 kDa viral protein within the cytoplasmic membrane of the infected cells, were used to determine epitopic differences among a number of virus clones derived from various isolates. All of the non-African isolates examined contained two epitopically different groups of virus clones, and the reaction profiles obtained were distinctly different from those obtained with the clones of an African isolate (Tengani). It was concluded that an ASFV isolate is composed of a biologically diverse virus population with distinctly different members which are only identified after cloning.

African Swine Fever↗