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Biomedical subjects

K Kajiwara

Publications and source records attributed to K Kajiwara.

At least 109 records · Page 6Linked to original sources

Noninvasive measurement of blood glucose concentrations by analysing Fourier transform infra-red absorbance spectra through oral mucosa.

Whether Fourier transform infra-red spectroscopy with an attenuated total reflection prism could be applied for noninvasive glucose measurement through oral mucosa was evaluated. As a result, the same absorbance peak at 1033 cm-1 as in glucose aqueous solution was found in the absorbance spectra through mucous membrane. However, these glucose specific peaks were interfered with by the baseline drifts owing to prism attachment and the background spectra from body constituents other than glucose. Therefore, to eliminate these interferences, the calibration curve between the second derivatives of the absorbance peak at 1033 cm-1 and those at 2920 cm-1 was calculated (r = 0.910). By using this calibration curve, the spectral changes due to prism attachment were first eliminated. Secondly, by obtaining the second derivative of the difference between the postprandial absorbance peak and the fasting sample as a characteristic of an individual, high correlations between the corrected second derivatives of absorbance spectra through the mucous membrane of the lip at 1033 cm-1 and the increases in blood glucose concentrations above fasting levels were observed (r = 0.910). In conclusion, it was suggested that Fourier transform infra-red spectroscopy could be useful for noninvasive monitoring of glucose through oral mucosa.

Blood Glucose↗

A null mutation in the human peripherin/RDS gene in a family with autosomal dominant retinitis punctata albescens.

The murine rds (retinal degeneration slow) allele is a semidominant null allele that causes photoreceptor degeneration. The wild-type sequence at the rds locus encodes a photoreceptor disc membrane protein named peripherin/RDS. Mutations in the homologous human peripherin/RDS gene can cause autosomal dominant retinitis pigmentosa, but these are missense mutations or deletions of single codons. No obvious null alleles have been reported in humans, so that the human phenotype corresponding to rds is as yet unknown. Here we report a 2-basepair deletion in codon 25 of the human gene in a family with autosomal dominant retinitis punctata albescens, suggesting that this disease, rather than retinitis pigmentosa, is the comparable human phenotype.

Alleles↗

Interaction of Streptomyces subtilisin inhibitor (SSI) with Streptomyces griseus metallo-endopeptidase II (SGMP II).

We have unexpectedly found that Streptomyces subtilisin inhibitor (SSI) and some other similar serine protease inhibitors produced by Streptomycetes strongly inhibit Streptomyces griseus metallo-endopeptidase II (SGMP II) [Kajiwara, K. et al. (1991) J. Biochem. 110, 350-354]. In order to elucidate the mode of their unusual interaction with SGMP II in more detail, we prepared twelve kinds of SSI analogues, in which one or two amino acid residues in the peptide segment from Thr64 to Val74 of wild-type SSI had been replaced or deleted by site-directed mutagenesis, and determined the dissociation constants of their complexes with SGMP II. Six analogues among them showed dissociation constants one order of magnitude lower than that of the wild type. Three had higher values. The results suggest that at least some residues in this segment are interacting with SGMP II in the complex. We also prepared an SSI mutant in which the disulfide bridge between Cys71 and Cys101 had been eliminated by replacing the two Cys residues with Ser residues. This mutated SSI inhibited SGMP II as strongly as the wild-type SSI did. While peptide bonds in the wild-type molecule did not suffer from the hydrolytic action of SGMP II except those at the amino-terminal fragile portion, the Pro72-Met73 bond of the mutant was specifically cleaved by the enzyme. This peptide bond, therefore, seems to play the role of the reactive site in the interaction of SSI with SGMP II.

Amino Acid Sequence↗

Possible role of CD5+ B cells expressing CD23 in mediating the elevation of serum-soluble CD23 in patients with rheumatoid arthritis.

Since increased levels of serum soluble CD23/Fc epsilon RII (sCD23) were evidently demonstrated in patients with autoimmune diseases such as rheumatoid arthritis (RA), the possible mechanisms responsible for the elevation of serum sCD23 were investigated in RA patients. In keeping with increased serum sCD23, high proportion of CD23+ B cells was detected in the patients; this was associated with the enhanced expression of only Fc epsilon RIIa mRNA. Upon incubation at 37 degrees C, peripheral blood mononuclear cells of the patients spontaneously released high levels of sCD23 into the culture supernatant, while the CD23 expression on their B cells was considerably maintained even after the culture. Dot blot analysis further revealed that in contrast to normal subjects, RA patients showed no complete disappearance of Fc epsilon RIIa mRNA after the spontaneous culture. In addition, sCD23 release was significantly reduced in the patients by the addition of cycloheximide. It was also found that cycloheximide exerted the inhibitory influence on the spontaneous culture-mediated expression of CD23 on CD5+ but not CD5- B cells of the patients. However, the disappearance of CD23 from CD5+ as well as CD5- B cells of cord blood samples was unaffected by the agent. These results strongly suggest that CD5+ B cells of RA patients may be specifically activated by some mechanisms responsible for the persistent expression of Fc epsilon RIIa mRNA leading to the accelerated turnover of CD23 and in turn the increased release of sCD23.

Adult↗

Aldose reductase inhibition and the phosphorus-31 profile of the intact diabetic rat lens.

Diabetic metabolic change and response to aldose reductase inhibition in the Wistar rat lens were examined with phosphorus-31 (31P) nuclear magnetic resonance (NMR) spectroscopy. To avoid artifacts in sample preparation, we used freshly excised lenses and acquired NMR data for 20 min immediately after lens extraction. The results showed a diabetes-induced time-dependent loss of ATP and phosphorylcholine (PC), an increase in alpha-glycerophosphate (alpha-GP) and inorganic phosphate and the appearance of sorbitol-3-phosphate (S-3-P) and fructose-3-phosphate (F-3-P). Oral but not topical dosing of an aldose reductase inhibitor, 5-(3-ethoxy-4-pentyloxyphenyl)-2,4- thiazolidinedione, resulted in a positive dose-response correlation characterized by a restoration of PC, S-3-P and F-3-P to the prediabetic level; however, alpha-GP and ATP were only partially normalized. The significance of the 31P change was further discussed.

Adenosine Triphosphate↗

Investigations of the architecture of tamarind seed polysaccharide in aqueous solution by different scattering techniques.

The architecture of tamarind seed polysaccharide (TSP) has been investigated by light scattering (LS), small angle X-ray scattering (SAXS) and synchrotron radiation scattering (SRSAXS). The experimental data show that TSP in aqueous solution consists of multi stranded aggregates, with a high degree of particle stiffness. The angular dependence of the scattered intensity is typical for wormlike chains. Data evaluation on the basis of this model yields a statistical Kuhn segment length lK = 150 nm. The cross sectional radius of gyration is estimated as Rgcs = 6.0 +/- 0.5 A, which is more than twice the value, published for single stranded polysaccharides. Correspondingly, the experimental value of the linear mass density, measured by LS, is about five times higher than the theoretical value calculated from the primary structure.

Light↗

[Pituitary non adenomatous tumor (Rathke's cleft cyst)].

Rathke's cleft cyst is one of many kinds of pituitary non-adenomatous tumors. Rathke's cleft cysts were evidenced by surgery in 7 cases from 7 to 87 years old. After the era of CT scan and MRI some cases were found incidentally after the head injury. Symptoms and signs of cases with Rathke's cleft cyst were headache, visual disturbances and/or diabetes insipidus. The lesion was high density on plain CT images and showed no-enhancement. The lesion on 2/3 cases showed high intensity on T1 weighted images and the others low. The lesion in half showed iso-intensity on T2 weighted images and in other half high intensity. The stalk was deviated to lateral side in a case. Half lesion was in the sella and half was in supra-sellar region. The cyst was present in both intra-sellar and supra-sellar region in a case and showed a dumb-bell type. There are three approaches for removal of Rathke's cleft cyst. Hardy's transnasal approach was used on intrasellar type. The trans-Sylvian or anterior trans-interhemispheric approach was used on supra-sellar type. Content in the cyst was evacuated totally, and the cyst wall was removed as much as possible. However, the stalk should be protected from damage.

Adolescent↗

[A study of infusional port re-insertion in patients with liver metastasis].

We evaluated the importance and usefulness of re-insertion of the intra-arterial infusion catheter in 10 patients with liver metastasis who showed problems in the catheter or system during intra-arterial infusion chemotherapy. The route of re-insertion was laparotomy-->left subclavian method in 3 patients, left subclavian-->left subclavian method in 5, and left subclavian-->femoral method in 2. The cause of re-insertion was dislocation in 5 patients, obstruction of the system in 4, and obstruction of CHA in 1. In the patients showing dislocation, re-insertion was performed after a mean of 4 months, and CEA improvement and direct effects evaluated by imaging techniques were marked, suggesting good indication. In the patients showing system obstruction or CHA obstruction, re-insertion was performed after a mean of 8.6 months, and CEA improvement and direct effects were less than those in the patients showing dislocation. Of the 10 patients who underwent re-insertion, 5 have survived to the present for 13-20 months (mean, 17 months). The prognosis of liver metastasis may be improved by active re-insertion of the intra-arterial infusion catheter.

Aged↗

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↗

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↗

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↗

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↗

[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↗

[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↗

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↗

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↗