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Biomedical subjects

M Katagiri

Publications and source records attributed to M Katagiri.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Analysis of 33C4 monoclonal antibody associated with aggregation of human B lymphocytes].

Interaction between immunocytes is essential for immune response to occur, and the part of it is mediated by cell adhesion mechanisms. However, little is known about the nature of homotypic adhesion between B cells. In order to investigate the mechanisms underlying the B cell adhesion, we tried to identify molecules involved in the adhesion process by raising monoclonal antibodies (mAb) against human B lymphoblastoid cell line WT46. One mAb. 33C4, reacted with all B cells, a part of T cells, and myeloma cells. Interestingly enough, 33C4 mAb induced aggregation of B cells, but not of T cells or other cells. Structural analysis showed that 33C4 molecule is a monomer of 45 kilodaltons with isoelectric point of 5.9. It is thus likely that 33C4 is a unique molecule involved in B cell aggregation and is clearly distinct from other cell adhesion molecules such as LFA-1, ICAM-1, and LFA-3. The mechanisms of aggregation induced by 33C4 mAb, however, remains to be determined.

Antibodies, Monoclonal↗
PubMed1989

[Aberrant expression of major histocompatibility complex class II. (HLA-DR/DQ) antigens and proliferative nuclear antigen. (Ki-67) in renal tubular epithelial cells].

In an attempt to clarify the participations of cellular immunity in the development of tubulo-interstitial lesions, aberrant expressions of major histocompatibility complex (MHC) class II antigens and Ki-67 nuclear antigen on the renal tubular epithelial cells were studied. Ki-67 antigen was known to appear in all phases of cell cycle except for Go. Nine normal kidney specimens (4 males and 5 females) and 117 kidney specimens obtained from patients with kidney diseases (54 males and 63 females) were examined with the indirect immunofluorescence technique using murine monoclonal antibodies against HLA-DR (lal), HLA-DQ (Leu10) and Ki-67 nuclear antigen. Patients included 100 with glomerular diseases, and 16 with tubulo-interstitial diseases consisting of 4 acute tubular necrosis (ATN), 7 acute tubulo-interstitial nephritis (AIN), one renal allograft rejection and 4 sarcoidosis. In normal kidney, HLA-DR was solely noted in only two specimens (22.2%) at the basal portion of proximal tubular epithelial cells. In tubulo-interstitial diseases 11 (68.8%) out of 16 patients showed diffuse and intense expressions of HLA-DR concomitant with HLA-DQ in 6 of 13 (42.9%), and 11 of 13 (84.6%) were positive for Ki-67 nuclear antigen. Especially, in AIN and allograft rejection, intense expression of HLA-DR, DQ and Ki-67 nuclear antigen were observed in 100%, 86%, 100%, respectively. In ATN 3(75%) were positive for HLA-DR and Ki-67, but not for HLA-DQ. In contrast, only 12(15.6%). 2(2.6%) and 2(4.8%) of primary glomerular disease were weakly positive for HLA-DR, DQ and Ki-67 nuclear antigen, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Clinical and histopathological studies of the suture made of DCFF-treated natural collagen fiber].

Natural and synthetic fiber sutures used clinically, especially twist or braid type ones, will remain to the region after healing by the first intention and often cause inflammation by capillarity. It is necessary to remove those sutures from healing wounds. To obviate this necessity, we separated collagen fibers from a tendon of a rat's tail, gave them DCFF treatment for immunological tolerance, and made collagen sutures on an experimental basis. The discussion on the clinical, histopathological and physical properties of the collagen sutures proved their superiority over any other type of suture currently used. (DCFF treatment: decalcifying, defatting and freeze-drying a material previously fixed in formalin.) 1. Results of Clinical Application: Collagen sutures immersed in 70% ethanol, contacting saliva, were easily handled and fell off spontaneously in about 7 days after operation. Thus removing sutures aren't necessary. 2. Histopathological Characteristics: (1) Biopsy observations show that the collagen sutures disclosed outside of the tissues were gradually decomposed by the activity of microbes in the oral cavity, falling off spontaneously in 7-10 days by the time of healing by the first intention, whereas those inside the tissues were more slowly absorbed. (2) The major portion of the collagen sutures, implanted in the dermis of a rat's back, was decomposed and absorbed in one week or 3 months at latest, with some portion encapsulated. All nylon sutures remained without being decomposed; most silk sutures, neither easily decomposed nor encapsulated, remained and occasionally caused distinct inflammatory rejection. 3. Physical Characteristics (load and elongation test): A tensility comparison between silk sutures (4-0 U.S.P. standard) with the collagen sutures of the same thickness showed the collagen sutures were stronger than the silk ones when they are wet.

Animals↗
PubMed1989

[Influence of pregnancy on IgA nephropathy].

In an attempt to clarify the influence of pregnancy on the natural course of IgA nephropathy, the courses of 79 pregnancies occurring in 47 patients with the disease were studied. These resulted in 3 artificial and 10 spontaneous abortions, and two pre-term and 64 full-term deliveries. Fifty four maternity passbooks were analyzed. In 22 pregnancies (40.7%) proteinuria was increased during the third trimester, and in 13 (76.5%) of 17 pregnancies receiving postpartum urinalysis, urinary protein was decreased to the level of the first trimester within one month after delivery. In two of the remaining four patients with a persistent increase in proteinuria, renal biopsy was carried out two months after delivery, revealing focal glomerular sclerotic lesions, in addition to mild mesangial proliferation compatible with IgA nephropathy. These findings indicated that increased urinary protein observed in the two pregnancies might be attributed to a complication of pre-eclamptic focal glomerular sclerosis rather than exacerbation of underlying IgA nephropathy. The glomerular filtration rate (GFR), examined in 27 patients both before and after pregnancy, was decreased in only two patients (7.4%), but these reductions appeared to go with the individual natural course. In 6 (15.0%) of 40 pregnancies, proteinuria was increased within one month after delivery, and one of them was diagnosed both clinically and pathologically as the acute exacerbation of IgA nephropathy. These data suggest that patients with IgA nephropathy might show transient acute exacerbation just after delivery rather than during pregnancy, and that even if such exacerbations occurred, pregnancy might have little influence on the natural course of the disease.

Adult↗
PubMed1989

[Clinico-statistical study of inpatients and autopsied cases in our clinic].

The statistics of clinical observation at Department of Internal Medicine, Nippon Dental University at Niigata from July 1981 to December 1987 (duration 6.5 years) were as follows: Total number of inpatients: 1,238, Total number of death cases: 106. Findings include: 1) Ratio of male patients to female patients 1.34:1.00. Male deceased patients to female deceased patients 1.52:1.00. 2) Average patients number hospitalized per year was 200. The high percentaged of certain advanced aged groups was reflected by the recent demographic changes in the society in general.; in their 60's 46.0%, in their 70's 24.3%, in their 80's 6.7%. In these age groups, female number is tendency to increase the number of male. 3) The diseases of inpatients were mostly due to the digestive tract, which accounted for 60.4% of the total. Of this percentage, 65% was due to hepato-biliary diseases. 4) The death statistics of malignant tumor was 68.9%; Benign diseases being 31.1%. Male patients died from hepatocellar carcinoma, lung cancer, colon cancer and stomach cancer, in descending order. Females died from cancer of the biliary tract, stomach cancer and hepatocellular carcinoma, again, in descending order. 5) 71.7% of all deaths were caused by the digestive tract, in particular, hepatocellular carcinoma, cancer of the biliary tract, liver cirrhosis and primary biliary cirrhosis, all belonging primarily to the hepato-biliary disease group. 6) As a result of 58 autopsies performed for 106 death cases, 32 cases had complete autopsies and 26 cases had partial organ punctures.

Aged↗
PubMed1988

Aromatase and nonaromatizing 10-demethylase activity of adrenal cortex mitochondrial P-450(11)beta.

19-Oxoandrostenedione, the product of 19-hydroxyandrostenedione by the 19-oxidase activity of the purified P-450(11)beta system of adrenal cortex mitochondria, was further oxidized and demethylated at the 10-position to give the C18-steroids, estrone (aromatase reaction) and 19-norandrostenedione (nonaromatizing 10-demethylase or C10-19 lyase reaction). These reactions, together with the initial hydroxylation of androstenedione at C19, form a sequence of P-450(11)beta-catalyzed C19-steroid 19-monooxygenase reactions. P-450(11)beta is thus similar to placental endoplasmic P-450AROM in some of its substrate specificity, but the two forms of P-450 appear to be different in both physiology and properties.

Adrenal Cortex↗
PubMed1988

Differential regulation by Ly-5 and Lyb-2 of IgG production induced by lipopolysaccharide and B cell stimulatory factor-1 (IL-4).

We have previously shown that mAb Ly-5 which on B cells recognizes a 220,000-Da (B220) molecule, inhibits LPS-induced IgG responses without affecting IgM or proliferative responses, whereas mAb Lyb-2 which modulates B cell activation processes induced by B cell stimulatory factor-1 (BSF-1) or IL-4, has no effect on LPS-induced B cell responses. In this report we further examined the cellular mechanisms of Ly-5 antibody action and the effect of Lyb-2 antibody in IgG responses induced by LPS and BSF-1. The results presented demonstrated that the inhibitory effect of Ly-5 antibody seems to be restricted to the IgG class and is observed in all IgG subclasses induced by LPS. Limiting dilution analysis showed that the Ly-5 antibody reduces primarily the precursor frequency of IgG-secreting cells and that the effect on the clone size is partial. Lyb-2 antibody, on the other hand, greatly inhibited IgG1 induction initiated by LPS and BSF-1 by the action on processes triggered by BSF-1, although it could not reverse the reduced IgG2b or IgG3 responses. Limiting dilution analysis revealed that Lyb-2 antibody reduces the precursor frequency but not the clone size of BSF-1-induced IgG1-producing cells, supporting our previous proposition that Lyb-2 plays a critical role in the B cell differentiation mediated by BSF-1. Taken together, these results indicate that both Ly-5 and Lyb-2 are important molecules in IgG subclass regulation, each acting on a distinct activation step.

Animals↗
PubMed1988

Effect of the dietary alpha-linolenate/linoleate balance on leukotriene production and histamine release in rats.

Rats were fed semi-purified diets supplemented either with safflower seed oil rich in linoleate (18:2n-6) or with perilla seed oil rich in alpha-linolenate (18:3n-3) through two generations. In the major phospholipids of polymorphonuclear leukocytes (PMNs), the proportions of n-6 polyunsaturated fatty acids (18:2, 20:4, 22:4 and 22:5) were higher but those of n-3 acids (20:5, 22:5 and 22:6) were lower in the safflower group than in the perilla group. When stimulated with a calcium ionophore, the PMNs from the safflower group produced 27% more leukotriene (LT)B4 than those from the perilla group. The formation of LTB5 which has biological activities less than 1/10 those of LTB4, was negligible in the safflower group but was 40 ng/10(7) PMN cells in the perilla group. The amount of the total LTB formed in the perilla group tended to be more than in the safflower group. The formation of SRS-A (slow-reacting substances of anaphylaxis) by PMNs was determined by measuring the spasmogenic activities of LTs on guinea pig ileum. SRS-A activity was 59% higher in the safflower group than in the perilla group. In contrast, histamine release from rat peritoneal mast cells was not significantly different between the two groups. Thus, the increasing the alpha-linolenate/linoleate ratio of diets results in the decreased formation of LTs derived from 20:4n-6 in PMNs. This may be beneficial in lowering the severity of allergic and inflammatory responses caused by LTs, and thereby shifting the pathological symptoms to normal self-defense mechanism.

Animals↗
PubMed1988

Characteristics of glomerular lesions in hepatitis B virus infection.

In an attempt to clarify a participation of hepatitis B virus (HBV) in the development of hepatic glomerulopathy in adults, kidney specimens obtained from 151 patients with liver diseases were studied. Although mesangial proliferation was more severe in patients with chronic hepatitis or liver cirrhosis than in those with acute hepatitis, no significant difference was observed between 82 serum hepatitis B surface antigen (HBsAg)-positive (HBV-related group) and 69 negative patients (HBV-nonrelated group). However, double contours of the glomerular capillary walls were observed more often in the former group (18/82, P less than .01), especially in the HBeAg-positive subgroup (8/24, P less than .001), than in the latter (3/69). In addition, glomerular capillary spike formation or a bubblelike appearance was observed in seven patients of the former group. Of these, all five patients examined were HBeAg-positive in their serum. By electron microscopic studies, subendothelial dense deposits and mesangial interpositions were observed more frequently in the HBV-related group, and subepithelial deposits were found only in the HBeAg-positive subgroup. The immunofluorescence study revealed IgA-dominant mesangial deposition in both HBV-related and nonrelated groups. As for the capillary wall deposits, however, IgG was dominant in 13 of the HBV-related group, but only one of the nonrelated group (P less than .01). Furthermore, one patient in the HBV-related group showed capillary wall-dominant HBeAg combined with IgG deposition.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1988

Accumulation of iodine-131 and technetium-99m pertechnetate in thyroid carcinoma.

Carcinoma of the thyroid is usually delineated as a cold defect on images with radioiodine and Tc-99m per-technetate. However, several cases that showed an accumulation of Tc-99m pertechnetate in thyroid carcinoma or in their metastases, but did not show any accumulation of radioiodine, have been reported. This paper presents a rare case of an advanced follicular adenocarcinoma of the thyroid that accumulated both Tc-99m pertechnetate and I-131. In this 41-year-old male patient, there were two primary foci in the thyroid; one occupied the whole left lobe with extension to the mediastinum and the other located in the lower part of the right lobe. In addition, there was a lymph node metastasis in the upper mediastinum adjacent to the left lobe. On images with both I-131 and Tc-99m pertechnetate, the tumor in the left lobe and the metastatic lymph node were delineated, but the tumor in the right lobe was not. Accumulation of Tc-99m pertechnetate in the lower part of the tumor of the left lobe was more distinct than that of I-131. Therefore, it is considered that despite similar histologic findings the trapping ability of the cancerous tissue differed from area to area.

Adenocarcinoma↗
PubMed1987

Interaction of heme with a synthetic peptide mimicking the putative heme-binding site of histidine-rich glycoprotein.

We synthesized a hexapeptide, Gly-His-His-Pro-His-Gly, previously identified as a tandem motif in the histidine-rich glycoprotein (HRG) which has multiple heme-binding sites. Binding of heme to the peptide was demonstrated by the characteristic difference spectrum showing a close resemblance to that of HRG, implying that the peptide binds heme through biaxial coordination with histidine imidazoles. Furthermore, the EPR spectra of the heme-peptide and heme-HRG complexes were almost completely identical in pattern, showing signals characteristic of the low spin iron. The results suggest that the synthetic peptide simulates the heme-binding properties of HRG and that each tandem motif in HRG serves as a unitary binding site for heme.

Binding Sites↗
PubMed1987

A sensitive method for quantitation of steroid hydroxylase activities of individual P-450 in tissue homogenates.

Assay methods which allow measurements of the level of individual P-450's in a homogenate of steroidogenic tissues have been developed. The assay is based simply on the determination of the specific products of steroid monooxygenase reactions under conditions in which sufficient amounts of the purified electron-donating components as well as lipids and detergents are supplemented so that the membrane-associated P-450 is able to exhibit its maximum activity. Under these conditions, an at least 10-fold increase in the NADPH-dependent monooxygenase activity of P-450 occurred as compared to that measured in the unenriched system. In addition, the present assay used ascorbate as an O2- -scavenger which effectively prevented possible inhibition caused by initiation of O2- -formation. Under the present assay conditions, nearly quantitative recovery of activities was accomplished of each purified P-450 that had been added to the homogenates as an internal standard. Furthermore, the high sensitivity of this assay allows the measurement of P-450 in small specimens (at least 100 mg of tissues), and could be used for measurements in autopsied cases or the glands of small animals.

Adrenal Glands↗