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Biomedical subjects

K Kajiwara

Publications and source records attributed to K Kajiwara.

At least 19 recordsLinked to original sources
PubMed1992

Glial fibrillary acidic protein (GFAP) expression and nucleolar organizer regions (NORs) in human gliomas.

The frequency of nucleolar organizer regions (NORs) in each glioma tissue and the relation between the expression of glial fibrillary acidic protein (GFAP) and the frequency of NORs was investigated. The number of Ag-NORs per cell for glioblastoma multiforme was significantly higher than that for anaplastic astrocytoma (P less than 0.05) and that for astrocytoma (P less than 0.01). The number of Ag-NORs per cell for GFAP-positive cells was significantly lower than that for GFAP-negative cells in each histopathological grade (P less than 0.01). Moreover, the linear relationship was demonstrated between the Ag-NORs numbers of GFAP-negative cells and bromodeoxyuridine (BUdR) labeling indices. From these results, it is concluded that many GFAP-positive glioma cells may have low growth potential in glioma tissue and GFAP-negative cells may have a close relation to cell proliferation. The combination of immunohistochemical and silver colloid staining is a useful method for investigating the biological characteristics of brain tumors.

Astrocytoma↗
PubMed1992

JPEG compression for PACS.

In the medical field, especially in diagnostic radiology, there still remains controversy over how and whether or not to compress X-ray images for storage and transmission. The joint Photographic Expert Group (JPEG) standard which has recently been agreed upon is the very attractive technique to archive and to transport images in medical fields. This technique is based on 'lossy' compression of images, which can handle not only X-ray images but also full-colored images, and is suitable for introduction into picture archiving and communicating systems (PACS). The images can be handled after compression as quite small clusters of data. For example, a single 2000 x 2000 x 12 bits chest X-ray image which is an 8 Mbyte image compressed at a 10:1 ratio could retain virtually all the visible quality of the original version, and would take 100 s to transmit at 64 kbits/s using the Integrated Services Digital Network (ISDN, 800 kbytes compressed file, 8 kbytes/s transmission theoretically). An important factor in the design of this technique is that this format relies on no specific hardware or software if using JFIF (JPEG File interchange Format). Soon this algorithm will be able to run on any workstation or on any PC in the world. Highly compressed images may be unsuitable for diagnostic purposes. However, they may be sufficient for reference images which will be needed in clinical fields.

Algorithms↗
PubMed1992

Cytologic evaluation of conjunctival epithelium after cataract surgery.

Although numerous studies have examined corneal epithelial wound healing, few reports describe conjunctival wound healing. Thus, we evaluated the conjunctival epithelium by brush cytology, in which a miniature brush was used to collect many cells relatively noninvasively. The temporal and superior conjunctivae were examined before and after cataract extraction on the first, third, seventh, and fourteenth days and then the first, second, and third months postoperatively, in a group of 20 patients (9 men and 11 women with a mean age of 69 years 3 months +/- 10 years). The cells collected were stained by the Papanicolaou method. Each postoperative specimen contained keratinized, polygonal, round, columnar, elongated, and inflammatory cells, as well as cells with nuclear alterations. No keratinized, elongated, or inflammatory cells were observed preoperatively. In contrast, columnar cells, which were present preoperatively, decreased during the wound healing process. Such nuclear changes as chromatin formation or the appearance of snake-like figures were observed in several patients postoperatively. These cellular changes may represent altered differentiation during the healing process. However, the conjunctival epithelium returned to normal within 2 months postoperatively in all patients.

Aged↗
PubMed1992

Establishment of a sensitive radioimmunoassay for the detection of human IgE-binding factor (soluble CD23).

A monoclonal antibody (mAb) specific to low-affinity receptor for IgE (FceRII/CD23) was established by the fusion of spleen cells of BALB/c mice immunized with the FceRII+ human B lymphoblastoid cell line (RPMI 8866) with mouse myeloma P3U1. Four mAbs, 10/3 (IgG1), 11/4 (IgG1), 12/2 (IgG2b) and 15/6 (IgM), almost completely inhibited the IgE binding to FceRII+ cells but not to FceRII- cells. More directly, they were demonstrated to react only with 43-kD component/FceRII of the cell lysate of RPMI 8866 cells by sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blot analysis. Since they have a different epitope specificity, a solid-phase radioimmunoassay (RIA) for the measurement of IgE-binding factor (IgE-BF) was established. It was found that the RIA with the use of 10/3 and 125I-labeled 11/4 or 12/2 gave good results in the detection of IgE-BF derived from B cells and monocytes as well as of T-cell-derived IgE-BF. More importantly, serum IgE-BF was also quantitatively measured by this RIA. Although increased serum levels of IgE-BF were observed in atopic patients, serum IgE-BF was decreased rather than increased in patients with very high serum IgE. This phenomenon may be explained by the decreased ability of the patients' B cells to spontaneously release IgE-BF in vitro.

Animals↗
PubMed1992

[Ruptured aneurysm at the peripheral branch of the posterior cerebral artery with systemic lupus erythematosus].

We report a 73-year-old woman with systemic lupus erythematosus (SLE) in whom intracerebral and intraventricular hemorrhage developed secondary to a ruptured aneurysm on the peripheral branch of the posterior cerebral artery. We reviewed data on 22 patients (43 aneurysms) in previous reports of ruptured cerebral aneurysms associated with SLE, including our case. Of these aneurysms, 34 (79.1%) were located on the major artery, and 9 (20.9%) were located on the peripheral small artery. Fusiform aneurysms accounted for 27.9% of the total. The prognosis was poor, and 14 patients (63.6%) died. Direct aneurysmal surgery was performed in 11 patients (50%), but 4 patients died of other diseases associated with SLE.

Aged↗
PubMed1992

[Comparison of long-term outcome of closed mitral commissurotomy (CMC) versus open mitral commissurotomy (OMC) and mitral valve replacement (MVR)].

To predict the late result of percutaneous mitral balloon valvotomy (PMV), we studied long term outcome of CMC which is similar to PMV in terms of closed heart technic, comparing with those of OMC and MVR. 226 patients with mitral stenosis were studied. 117 patients had CMC, 72 had OMC and 37 had MVR. The cumulative follow up period in these groups were 1892 patient year, 632 patient year and 200 patient year respectively. Postoperative actual survival rate at 5, 10, 15 years in CMC patients were 95 +/- 2%, 91 +/- 3%, 86 +/- 3% respectively. No operative or late death was seen in OMC or MVR patients. Postoperative event free rate at 10 years in OMC or MVR patients (97 +/- 2%, 90 +/- 6%, respectively) were higher than that in CMC patients (79 +/- 4%). Thromboembolism developed in 7 (6%) CMC patients, and 4 of these patients died from cerebral embolism. No patient in OMC or MVR group had thromboembolism. Reoperation was done for mitral restenosis or regurgitation in 40 CMC patients. 15 (38%) of these patients were associated with pulmonary hypertension, and 22 (55%) patients had secondary tricuspid regurgitation. On the other hand, only 1 OMC patient and 1 MVR patient had reoperation due to restenosis or thrombosed artificial valve. These results suggest that PMV should be indicated for restricted cases of mitral stenosis.

Adult↗
PubMed1992

Spectroscopic quantitative analysis of blood glucose by Fourier transform infrared spectroscopy with an attenuated total reflection prism.

As an alternative way of long-term glycemic monitoring, the glucose measurement by analyzing Fourier transform infrared absorbance spectra with an attenuated total reflection prism has been developed. In glucose aqueous solution, glucose has characteristic absorptions at the wave numbers of 1033 and 1080 cm-1 and the absorption intensities are proportional to glucose concentrations. In serum and whole blood samples, however, red blood cell corpuscles, serum albumin and serum gamma-globulin interfere with the absorbance spectra of glucose and shift the base line upward significantly. Therefore, to eliminate these interferences in serum and whole blood samples, the feasibility of the calibration curves obtained by using difference absorbance spectra with those of fasting samples was studied. As a result, highly significant correlations between glucose concentrations estimated by Fourier transform infrared spectroscopic method and those measured by glucose oxidase method were obtained (r = 0.981 and 0.989 for serum and whole blood samples, respectively). From these experiments, it was concluded that by infrared spectroscopy glucose concentrations in the serum and whole blood samples could be measured quantitatively or monitored if the base line drifts and interferences were subtracted.

Blood Glucose↗
PubMed1991

Mutations in the human retinal degeneration slow gene in autosomal dominant retinitis pigmentosa.

The murine retinal degeneration slow (rds) gene is a semidominant mutation with a phenotype having rod and cone photoreceptors that develop abnormally and then slowly degenerate. The phenotype is a possible model for retinitis pigmentosa, one of the scores of hereditary human retinal degenerations, which is also characterized by photoreceptor degeneration. We report here three mutations of the human homologue of the rds gene (RDS) that cosegregate with autosomal dominant retinitis pigmentosa in separate families. Our results indicate that some cases of autosomal dominant retinitis pigmentosa are due to mutations at the RDS locus.

Adult↗
PubMed1991

Major histocompatibility complex expression in brain of rats with graft-versus-host disease.

In a healthy state, the central nervous system (CNS) is believed to be an immunologically privileged site, which does not participate in the immune reactions of the rest of the body, and in which identifiable components of the immune system are rare or non-existent. In this study, an immunohistochemical examination of the CNS of F1 hybrid rats following induction of graft-versus-host disease (GVHD) was carried out to determine whether specific immune reactions in the normal CNS could occur during a systemic immune reaction. The results revealed extensive parenchymal and vascular expression of class I and II major histocompatibility complex (MHC) encoded cell surface molecules. The strongest expressors of class I and II molecules were endothelial cells and parenchymal cells, respectively, the latter being apparently activated microglia, in the cerebrum and cerebellum of rats with GVHD. In addition, occasional scattered lymphocytes were detected in the CNS of GVHD rats without blood-brain barrier disruption. Thus, evidence was obtained for the presence of immune responses such as MHC antigen expression and lymphocyte infiltration in the CNS during a strong systemic immune response such as GVHD, microglia and endothelial cells apparently playing an important role.

Animals↗
PubMed1991

Purification and characterization of Streptomyces griseus metalloendopeptidases I and II.

Two metalloendopeptidases, designated as Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), were isolated from a commercial Pronase P by a method including affinity chromatography on carbobenzoxy-L-alaninyl-triethylenetetraminyl-Sepharose (Z-Ala-T-Sepharose). The two enzymes differed from each other in behavior on ion-exchange chromatography but showed the same amino-terminal sequence at least up to the 20th residue. Their molecular weights were both estimated to be 37,000 by SDS-polyacrylamide gel electrophoresis. Elemental and amino acid composition analyses indicated that both of them contained about 1 g atom of zinc and one cystine residue per mol of protein. Cleavage specificities of the two enzymes toward synthetic peptide-substrates were very similar to those observed with thermolysin. EDTA, o-phenanthroline, and phosphoramidon strongly inhibited these enzymes, while typical serine-protease inhibitors and cysteine-protease inhibitors had no effect. The findings clearly indicate that SGMPI and SGMPII can be classified into the family of zinc-endopeptidases. It was unexpectedly found, however, that these metalloendopeptidases were strongly inhibited by protein serine-protease inhibitors produced by Streptomycetes, such as Streptomyces subtilisin inhibitor (SSI), alkaline protease inhibitor-2c' (API-2c'), and plasminostreptin (PS).

Amino Acids↗
PubMed1991

Application of bimane-peptide substrates to spectrofluorometric assays of metalloendopeptidases.

A spectrofluorometric method for sensitive determination of metalloendopeptidase activity has been developed by using a bimane-peptide containing a tryptophan residue, i.e. 1,7-dioxo-2,5,6-trimethyl-1H,7H-pyrazolo[1,2-alpha]pyrazol-3-yl-methyl- thiomethylcarbonyl-phenylalanyl-tryptophanyl-leucine (Bim-SCH2CO-Phe-Trp-Leu-OH). Such an "intramolecularly quenched" substrate was originally designed for a sensitive assay of angiotensin I converting enzyme (ACE) [Sato, E. et al. (1989) Chem. Pharm. Bull. 37, 145-147]. All the typical metalloendopeptidases tested, such as thermolysin, Pseudomonas aeruginosa (Ps.) elastase, Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), and alkinonase A, a metalloendopeptidase from Streptomyces violaceorectus, cleaved this substrate strictly at a Phe-Trp bond, leading to a marked increase in fluorescence. Kinetic parameters of the enzymatic hydrolyses of five kinds of analogous bimane substrates were compared to examine how the nature of neighboring amino acid residues on either side of the cleavable bond affects the catalytic efficiency of each of the metalloendopeptidases. Bim-SCH2CO-Phe-Trp-Leu-OH was most efficiently hydrolyzed by all of these enzymes. The use of this substrate made it possible to determine minute amounts of metalloendopeptidases, especially those originating from Streptomycetes (for example, as little as 10 fmol of SGMPII).

Amino Acid Sequence↗
PubMed1991

Interactions of Streptomyces serine-protease inhibitors with Streptomyces griseus metalloendopeptidase II.

Streptomyces griseus metalloendopeptidase II (SGMPII) was shown to form tight complexes with several Streptomyces protein inhibitors which had been believed to be specific to serine proteases, such as Streptomyces subtilisin inhibitor (SSI), plasminostreptin (PS), and alkaline protease inhibitor-2c' (API-2c'), as well as with Streptomyces metalloprotease inhibitor (SMPI). The dissociation constants of complexes between SGMPII and these inhibitors were successfully determined by using a novel fluorogenic bimane-peptide substrate. The values ranged from nM to pM. The results of studies by gel chromatographic and enzymatic analyses indicated that SGMPII is liberated from the complex with SSI by the addition of subtilisin BPN'. SGMPII and subtilisin BPN' proved, therefore, to interact with SSI in a competitive manner, despite the difference in the chemical nature of their active sites.

Base Sequence↗
PubMed1991

Mild hypothermia ameliorates ubiquitin synthesis and prevents delayed neuronal death in the gerbil hippocampus.

BACKGROUND AND PURPOSE: The purpose of the present study is to determine the effect of mild hypothermia on the synthesis of ubiquitin, an important protein for maintenance of cell viability, in the hippocampal neurons following transient cerebral ischemia. METHODS: Transient ischemia was induced by occluding both common carotid arteries for 5 minutes. In experiment 1, the animals were divided into four groups according to the rectal and scalp temperatures during ischemia: the normothermia group and the graded hypothermia A, B, and C groups (n = 9 per group). CA1 neuronal density was assessed at 7 days after ischemia. In experiment 2, the animals were divided into two groups designated the normothermia and the hypothermia groups (n = 6 per group). The presence of ubiquitin was examined by immunohistochemistry at 6, 24, and 48 hours after transient ischemia in various regions of the hippocampus. RESULTS: In experiment 1, the mean +/- SEM neuronal density per millimeter was 12 +/- 1 in the normothermia group and 126 +/- 25, 225 +/- 10, and 214 +/- 9 in hypothermia groups A, B, and C, respectively. Mild hypothermia in groups B and C, in which the brain temperature was below 33 degrees C, ameliorated markedly the extent of ischemic neuronal damage in the CA1 sector (p less than 0.01). In experiment 2, ubiquitin immunoreactivity had disappeared in all regions of the hippocampus at 6 hours after ischemia and showed no subsequent recovery in the CA1 pyramidal neurons under normothermic conditions. Under hypothermic conditions, however, it had recovered significantly in the CA1 pyramidal neurons at 24 and 48 hours after ischemia (p less than 0.01). CONCLUSIONS: We conclude that mild hypothermia, in which the brain temperature is below 33 degrees C, markedly improves the ischemic delayed neuronal damage in the CA1 sector, and that increased ubiquitin synthesis and protein ubiquitination could be one essential part of the protective mechanism afforded by mild hypothermia against delayed neuronal death.

Animals↗
PubMed1991

An artificial endocrine pancreas--problems awaiting solution for long-term clinical applications of a glucose sensor.

The artificial endocrine pancreas is a feedback controlled system regulating insulin delivery on a minute-by-minute basis according to measured blood glucose levels. The bedside-type artificial endocrine pancreas has been proven to be useful not only as a therapeutic tool for diabetic patients but also as an elegant research tool for investigating the pathophysiology of the disease. Recently, a wearable-type, closed-loop system has been developed, of which the breakthrough was the establishment of a needle-type glucose sensor. However, for the long-term clinical use of needle-type glucose sensors, several obstacles remain to be solved, such as oxygen dependency, biocompatibility of the membrane, etc. The most promising method for the non-invasive determination of blood glucose is infrared spectroscopy. The trend in the development of a closed-loop glycemic control system which enables perfectly physiological glycemic regulation on a long-term basis is directed to an implantable device. Much research is being conducted to realize such devices.

Alginates↗
PubMed1991

[A study on hepatic arterial infusion for metastatic liver tumor].

This study was designed to evaluate whether hepatic arterial infusion is effective in terms of response rate and survival time of patients with unresectable liver metastasis from colorectal and gastric cancer. In 19 patients with liver metastasis from colorectal cancer, one patient had a CR, 3 had a PR or MR and the remainder showed NC or PD, with an overall response rate of 16.7%. The response rate was higher in men than in women as well as in patients with metachronous liver metastasis. The dose schedules showed no effectiveness in patients with histologically well-differentiated adenocarcinoma. However, there was a statistical difference in survival time according to the response. The overall response rate in 7 patients with liver metastasis from gastric cancer was 42.9% with one patient achieving CR, 2 patients PR and the others PD. As a result, hepatic arterial infusion of antitumor regimen was an effective method for inoperable metastatic liver cancer.

Adenocarcinoma↗
PubMed1991

[Quantification of wallerian degeneration of the pyramidal tract in the capsular region by magnetic resonance imaging].

Using magnetic resonance imaging, we studied 23 patients with motor deficit associated with cerebrovascular disease of the internal capsule. According to the severity of the motor deficits, 23 patients were divided into three groups (severe group...9, moderately severe group...8, mild group...6). A coronal T2-weighted image was obtained along a straight line between the front edge of the medulla and the deepest point of the interpeduncular cistern in a midsagittal T1-weighted image. It was revealed that wallerian degeneration extended continuously from part of the internal capsule down to the pons or medulla or the decussation in all patients. The area of wallerian degeneration in the pons and the area of half the pons were calculated from the coronal T2-weighted image. Moreover, the wallerian index was calculated as: (area of wallerian degeneration in pons divided by area of half the pons) X 100. Values of the wallerian index +/- SD were 26.4 +/- 5.1 in the severe group, 19.2 +/- 5.6 in the moderately severe group, and 10.0 +/- 5.4 in the mild group. There were significant differences among the three groups. We concluded that the area of wallerian degeneration was related to the severity of motor deficits.

Adult↗