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Biomedical subjects

N Hashimoto

Publications and source records attributed to N Hashimoto.

At least 667 records · Page 37Linked to original sources
PubMed1984

Degradation and epimerization kinetics of moxalactam in aqueous solution.

The kinetics of epimerization and degradation of moxalactam in aqueous solution was investigated by HPLC. The pH-rate profiles of the degradation and epimerization were determined separately over the pH range of 1.0-11.5 at 37 degrees C and constant ionic strength 0.5. The degradation and simultaneous epimerization were followed by measuring both of the residual R- and S-epimers of moxalactam and were found to follow pseudo-first-order kinetics. The degradation was subjected to hydrogen ion and hydroxide ion catalyses and influenced by the dissociation of the side chain phenolic group. The epimerization rates were influenced significantly in the acidic region by the dissociation of the side chain carboxylic acid group and in the basic region by hydroxide ion catalysis. The pH-degradation rate profile of moxalactam showed a minimum degradation rate constant between pH 4.0 and 6.0. The pH-epimerization rate profiles of moxalactam showed minimum epimerization rate constants at pH 7.0. The epimerization rate constants of the R- and S-epimers were not very different.

Chemical Phenomena↗
PubMed1984

Augmented gastrin responses in diabetic patients with vagal neuropathy.

We evaluated serum gastrin responses to a test meal in normal subjects and diabetic patients with or without vagal neuropathy. Vagal neuropathy was defined as a heart rate variation during deep breathing of less than 9 beats/min. Forty-three percent (54 out of 124) of the diabetic patients had abnormal heart rate variation, compared with 5% (3 out of 53) of the normal subjects. Serum gastrin responses to a test meal were examined in 17 normal subjects, 20 out of 70 diabetic patients without vagal neuropathy and 17 out of 54 diabetic patients with vagal neuropathy. Meal-stimulated gastrin levels were significantly higher in the diabetic patients with vagal neuropathy than in the normal subjects, while the findings in the diabetic patients without vagal neuropathy were similar to those in normal subjects. These data suggest that augmented gastrin responses are due to vagal denervation induced by autonomic neuropathy.

Diabetic Neuropathies↗
PubMed1984

Extent of thermal penetration of Nd-YAG laser--histological considerations.

The extent of thermal penetration of Nd-YAG laser was studied histologically. The material was obtained from seven cases of various types of intracranial and extracranial tumours and normal temporal muscle obtained at operation. After irradiation of the tumour surface with the laser, the tumours were removed and depth and width of pathological changes caused by heat were studied. Histologically, materials consisted of a vaporized surface, carbonized, vesicular, necrotic, oedematous layer and surrounding intact brain tumour tissue. There was a direct relationship between the thermal effect and the irradiated thermal energy (watt x exposure time x pulse number). The results showed that the thermal effect was limited to a depth of 6 to 10 mm from the irradiated surface when irradiated 4 times at the power of 90 watts for 2 seconds.

Adult↗
PubMed1984

Location of intracranial aneurysms associated with cerebral arteriovenous malformation: statistical analysis.

Distributions of cerebral aneurysms by site were compared statistically in 78 reported cases associated with arteriovenous malformation, including our five cases, and cases with solitary intracranial aneurysms without arteriovenous malformation. When the feeder of an arteriovenous malformation was one of the branches of anterior, middle, or posterior cerebral arteries, the aneurysms were located on these respective arteries much more frequently than expected in the general aneurysmal population. This was statistically significant. Our results strongly suggest that abnormal hemodynamic stresses on the arteries from which the feeders branch out to arteriovenous malformations play a significant role in the development of intracranial aneurysms on these arteries.

Adult↗
PubMed1984

Acromegaly with multiple secreting pituitary adenomas.

A case of acromegaly with two separate growth hormone-secreting pituitary adenomas is presented. The multiplicity was suspected on computerized tomographic scan and confirmed at transsphenoidal surgery. Possible occurrence of multiple adenomas is discussed.

Acromegaly↗
PubMed1984

Biotin-labeled protein-A enzyme-linked immunosorbent assay for the detection of Japanese encephalitis antibody in sera from humans, swine and several animal species.

Biotin-labeled protein-A was incorporated into enzyme-linked immunosorbent assay (ELISA) for seroepidemiological surveys of Japanese encephalitis (JE) virus infection in several vertebrates. The ELISA could detect the JE antibody in sera from man, rhesus monkey, swine, horse, dog, rabbit and mouse by the same reagent, but not in sera from cattle and pigeon. The titers of ELISA antibody were almost the same as those of 2-ME resistant HI antibody. Since non-specific reaction in ELISA was very low in the sera of swine and humans, the cut-off titer for the assay could be set at 1:5 for positive antibody.

Animals↗
PubMed1984

Histological study of intestinal atresia due to intrauterine intussusception.

Histological studies were conducted on 4 patients with intestinal atresia due to intrauterine intussusception. This atresia is characterized by a polypoid lesion as the remnant of the invaginated and necrotized intestine in the distal intestinal lumen. As the result of the histological survey in the affected intestine, we tentatively classified this atresia into two types, type A and B. In type A, the polypoid lesion is observed at the blind end, with relatively good preservation of the structure of the intestine. In type B, the polypoid lesion is located apart from the blind end, and the lesion is markedly necrotic. The interruption of intestinal blood flow seemed to be more severe in type B than in type A.

Female↗
PubMed1984

Antigenic analysis of flaviviruses with monoclonal antibodies against Negishi virus.

Twelve monoclonal antibodies against Negishi virus were obtained and characterized by hemagglutination inhibition (HI) and neutralization (NT) tests using five flaviviruses isolated in the pan-Pacific region. The reaction pattern of the antibodies showed that Negishi virus was most closely related to Langat virus, followed by 3-Arch, JE and Apoi viruses in that order. Hemagglutinating (HA) antigen of the virus had distinct HI relating sites which were Negishi virus specific, tick borne encephalitis (TBE) virus complex specific and flavivirus cross-reactive. Monoclonal anti-Negishi antibodies cross-reactive to Japanese encephalitis (JE) virus in the HI test had neutralizing activity to JE virus but no activity to homologous Negishi virus.

Animals↗
PubMed1984

Preparation of complement fixation antigen of Chlamydia psittaci grown in tissue culture by treatment with beta-propiolactone.

A new method of preparing a chlamydial complement fixation (CF) antigen by treatment with beta-propiolactone (BPL) is presented. Chlamydia psittaci strains Pigeon-1041 and Budgerigar-No. 1, and Chlamydia trachomatis strain L2/434/BU, propagated in L-929 cell monolayers, were inactivated with BPL. This BPL-treated antigen was useful for detecting CF antibodies in both human and pigeon sera, and it did not cause false-positive reactions, as are sometimes observed between some human sera and phenol-treated antigen derived from eggs. When this CF antigen was treated with potassium periodate and tested for reactivity with mouse immune ascitic fluid, it was found that the antigen contained type- or strain specificity as well as genus specificity. Immunization with the BPL-treated antigen elicited type- or strain-specific neutralizing antibody.

Animals↗
PubMed1984

Russell body-like inclusions in oral B-lymphomas.

Two cases of oral B-lymphomas with numerous Russell body-like inclusions are described. One occurred primarily in the hard palate of a 59-year-old female with Sjögren's syndrome, and was diagnosed as lymphoplasmacytoid immunocytoma by Kiel's classification. The other occurred secondarily in the buccal mucosa of a 44-year-old female whose first affected site was orbital soft tissues, and was diagnosed as extramedullary plasmacytoma. The diagnostic problems and the nature of the Russell body-like inclusions are discussed based on the immunoperoxidase (PAP) method and electron microscopic study. The first patient is well without recurrence 19 months after surgery, while the second patient developed extramedullary plasmacytoma in the abdomen 5 months after surgery for the buccal plasmacytoma.

Adenoma, Pleomorphic↗
PubMed1984

Benign fibroblastic tumor-like lesion simulating malignancy in the maxilla.

A benign fibroblastic lesion simulating malignancy is reported. The lesion occurred in the right maxilla of an 11-year-old girl and perforated the outer cortical plate, suggesting malignancy. The biopsy, however, revealed proliferation of fibroblasts and fibrocytes with neither prominent atypia nor mitosis in a myxoid matrix. Electron microscopy showed that some fibroblastic cells were indeed myofibroblasts. As the lesion did not belong to any established entities, the final pathological diagnosis of benign fibroblastic lesion was made, leading to conservative surgery. The patient is well without recurrence 18 months after surgery.

Cell Nucleus↗
PubMed1984

Selective elimination of a B cell subset having acceptor site(s) for T cell-replacing factor (TRF) with biotinylated antibody to the acceptor site(s) and avidin-ricin A-chain conjugate.

A covalent conjugate of avidin with ricin subunit A-chain (avidin-RA) was prepared by using N-succinimidyl 3-(2-pyridyldithio)propionate as a coupling agent. Selective cytotoxic activity after the combined treatment of spleen cells with biotinylated antibody and avidin-RA was demonstrated by the fact that the responsiveness to LPS was selectively abrogated by pretreatment of the cells with biotinylated rabbit anti-mouse immunoglobulin (MIg) antibody, but not with biotinylated anti-Thy-1.2 antibody. Neither the biotinylated antibody alone nor avidin-RA alone was effective in decreasing the responses to mitogens. Moreover, a high anti-DNP PFC response elicited by DNP-KLH-primed BALB/c mouse spleen cells stimulated in vitro with DNP-KLH was mostly abrogated by the pretreatment of the cells with biotinylated anti-MIg antibody and avidin-RA. Again, neither the biotinylated antibody alone nor avidin-RA alone was effective in decreasing the anti-DNP PFC response. This cell-killing method with the use of biotinylated antibody and avidin-RA was applied and evaluated in experimental systems in which the helper action of T cells on B cells was mediated by T cell-replacing factor (TRF) or was performed by the direct interaction of T cells with B cells (cognate interaction). When DNP-KLH-primed splenic B cells, pretreated with biotinylated F(ab')2 fragment of DCF1 male anti-BALB/c-B IgG antibody against acceptor site(s) for TRF followed by treatment with avidin-RA, were stimulated with DNP-OVA in the presence of monoclonal TRF, the anti-DNP PFC response was significantly decreased, whereas the same treated B cells responded well to stimulation with DNP-PPD in the presence of Tbc-primed T cells (cognate interaction). These results indicate that B cells responsible for the cognate interaction and those having TRF acceptor site(s) belong to a distinct subpopulation of B cells, and that the cytocidal action of the noncovalent conjugate of the antibody and RA formed from the biotinylated antibody and avidin-RA via an avidin-biotin complex has immunologic selectivity, eliminating only the latter subset of B cells recognized by the antibody.

Animals↗