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Biomedical subjects

M Katagiri

Publications and source records attributed to M Katagiri.

At least 73 records · Page 4Linked to original sources

[Measurement of adenosine deaminase activity in bronchoalveolar lavage fluids as a tool for diagnosing miliary tuberculosis].

Measurement of the activity of adenosine deaminase (ADA) in pleural effusions has been reported to be useful in the diagnosis of tuberculous pleuritis. To determine whether ADA activity can also be used to diagnose miliary tuberculosis, it was measured in bronchoalveolar lavage fluid from 64 subjects: 6 patients with miliary tuberculosis, 21 patients with sarcoidosis, 15 patients with idiopathic interstitial pneumonia, 15 patients with other diseases, and 7 healthy controls. Mean ADA activity was 5.02+/-3.75 IU/L (mean+/-SD) in patients with miliary tuberculosis; 1.06+/-0.99 IU/L in patients with sarcoidosis; 0.21+/-0.43 in patients with idiopathic interstitial pneumonia; and 0.30+/-0.51 IU/L in healthy controls. The level in patients with miliary tuberculosis differed significantly from the others (p<01.01). All 6 patients with miliary tuberculosis, 3 patients with sarcoidosis, 1 patient with Wegener's granulomatosis, and 1 patient with lymphangitic carcinomatosis had levels of ADA activity in bronchoalveolar lavage fluid that exceeded 2.0 IU/L. With a cut-off value of 2.0 IU/L the sensitivity of this test to miliary tuberculosis is higher than that of other diagnostic aids. Measurement of ADA activity in bronchoalveolar lavage fluid may be of great value in the early diagnosis of miliary tuberculosis.

Adenosine Deaminase↗

[Chronic recurrent pulmonary thromboembolism associated with sedentary work].

A 32-year-old woman was hospitalized with recurrent left-sided chest pain and dyspnea on exertion, which had progressed for approximately 10 years. Since age 18 she had been spending more than twelve hours per day in a predominantly seated position on a floor mat, engaged in Japanese dressmaking. A chest roentgenogram showed marked dilation of the main pulmonary arteries, bilateral oligemia in the upper lung fields and a peripheral infiltration in the middle field of the left lung. The (99m)Tc-MAA perfusion lung scan showed multiple defects in both lungs, but no abnormal findings were detected on a 133Xe ventilation scan. A pulmonary angiogram showed multiple occlusions of pulmonary arteries in both lungs. Because recurrent chest pain and dyspnea had been present for a long time, and because ultrasonic cardiography revealed pulmonary hypertension repeatedly for several years, pulmonary thromboembolism was considered to be chronic and recurrent. The patient had none of the following risk factors for pulmonary emboli: malignancy, neurological disease, heart disease, obesity, pregnancy, or a congenital coagulative abnormality such as deficiency of AT-III, protein C, protein S, or plasminogen. Because no other cause could be found, the chronic recurrent pulmonary thromboembolism most likely resulted from extensive sedentary work that caused stagnation of venous return and deep vein thrombosis.

Adult↗

[Analysis of a novel gene expressed in apoptotic T-cell hybridoma treated with dexamethasone].

Developmentally and physiologically controlled cell deaths are called programmed cell death (PCD), and distinguished from accidental cell death while apoptosis is defined morphologically as a certain type of cell death (i.e. chromatin condensation, DNA fragmentation, organella compaction, and blebing of cell and nuclear membranes). Apoptosis is often associated with PCD. Most of cells undergoing PCD have been shown to require de novo synthesis of mRNA and protein. A number of genes have been reported to be expressed in apoptotic cells. In the immune system programmed cell death plays an important role in negative selection of immature T cells. Situations that result in programmed cell death include the withdrawal of cytokine from cultures of cytokine dependent cells, lysis of target cells by cytotoxic T cells, and activation of T cells. In T cells, another well described means of inducing apoptosis is an exposure to glucocorticoids. We cloned a novel gene expressed in apoptotic 2B4. 11 mouse T-cell hybridoma treated with steroid. This gene was not detected in vivo, but was so in mouse thymocytes and splenocytes cultured with dexamethasone and IgM stimulated mouse preB cell line WEHI-231. Thirty-six amino acids, position 2-37, has a 37% homology to mouse intracisternal A-particle gag p27 protein.

Amino Acid Sequence↗

Cytochrome P450s of isolated rat hepatocytes in spheroid and monolayer cultures.

The maintenance of cytochrome P450s (P450s) and NADPH-cytochrome P450 reductase (P450 reductase) in the monolayer and spheroid cultures of hepatocytes from male rats was examined. The content of total P450 in monolayer culture decreased to almost none after 144 hr, whereas the level in spheroid culture remained within 6-13% of initial values during an incubation period of 144-192 hr. P450 2C11, a major P450 in male rat, in monolayer cells rapidly decreased in 144 hr, while the level in spheroid cells after 144 hr and 192 hr maintained 25% and 15%, respectively, of initial level. On the other hand, P450 2A1 and P450 2E1 in both monolayer and spheroid cells rapidly decreased. P450 reductase in both cells showed a gradual decline reaching a level of 43-44% of the initial level at 96 hr, and remained within 16-17% of the initial value during an incubation period of 192 hr. These results indicate that P450 2C11 in spheroid cells maintained more stable than in the monolayer cells, and that P450 reductase in both cultures declined only moderately, compared with P450s.

Animals↗

Neuronal differentiation of Neuro 2a cells by lactacystin and its partial inhibition by the protein phosphatase inhibitors calyculin A and okadaic acid.

Lactacystin (1.3 microM), a metabolite from an actinomycete, induced the formation of bipolar projections at both sides of the cell body of Neuro 2a cells 1 day after treatment and networks at and after 3 days and enhanced acetylcholinesterase activity (a marker of neuronal differentiation). Thus, the neuronal differentiation was characterized both morphologically and functionally. The experiments with various inhibitors of protein kinases and phosphatases revealed that the protein phosphatase inhibitors calyculin A (0.5 nM) and okadaic acid (0.6 nM) inhibit the formation of bipolar projections at 1 day, but does not inhibit the network formation at and after 3 days.

Acetylcholinesterase↗

The role of cytochrome b5 in the biosynthesis of androgens by human P450c17.

Human cytochrome b5 has a profound effect on the 17,20-lyase activities catalyzed by purified, human cytochrome P450c17. It enhances the conversion of 17 alpha-hydroxypregnenolone to dehydroepiandrosterone by 13-fold and the conversion of 17 alpha-hydroxyprogesterone to androstenedione by at least 10-fold. This latter activity is virtually undetectable in the absence of cytochrome b5. Other activities catalyzed by P450c17 include 17 alpha-hydroxylation of progesterone and pregnenolone and are much less influenced by cytochrome b5. The conversion of pregnenolone to 17 alpha-hydroxypregnenolone is increased by 2-fold, while that of progesterone to 17 alpha-hydroxyprogesterone is unchanged. These studies using purified systems suggest that cytochrome b5 plays a role in regulating the activities of P450c17 to optimize the balance between sex hormone synthesis and glucocorticoid synthesis. In particular, they indicate that in human testes which contains a high b5/P450 ratio, 17 alpha-hydroxyprogesterone can serve as an intermediate in testosterone production, rather than being a dead-end product, or stated another way, because of the relatively high concentration of cytochrome b5 in the human testis, both the delta 4 and the delta 5 steroidogenic pathways can lead to testosterone production.

17-alpha-Hydroxypregnenolone↗

Exon-intron organization of Xenopus MHC class II beta chain genes.

The amphibian Xenopus laevis is the most primitive vertebrate in which the major histocompatibility complex (MHC) has been defined at the biochemical, functional, and molecular genetic levels. We previously described the isolation and characterization of cDNA clones encoding X. laevis MHC class II beta chains. In the present study, genomic clones encoding class II beta chains were isolated from X. laevis homozygous for the MHC f haplotype. Three class II beta chain genes, designated Xela-DAB, Xela-DBB, and Xela-DCB, were identified. Sequence analysis of these genes showed that Xela-DBB and Xela-DCB correspond to the previously characterized cDNA clones F3 and F8, respectively, whereas Xela-DAB encodes a third, hitherto unidentified class II beta chain of the MHC f haplotype. As a representative of X. laevis class II beta chain genes, the Xela-DAB gene underwent detailed structural analysis. In addition, the nucleotide sequence of Xela-DABf cDNA clones was determined. The Xela-DAB gene is made up of at least six exons, with an exon-intron organization similar to that of a typical mammalian class II beta chain gene. The 5'-flanking region of the Xela-DAB gene contains transcriptional control elements known as X1, X2, and Y, but lacks typical TATA or CCAAT boxes. A notable feature of the X. laevis class II beta chain genes is that the sizes of the introns are larger than those of their mammalian counterparts. As assessed by northern blot analysis, the three class II beta chain genes had similar expression patterns, with the highest level of transcription detected in the intestine. Identification of the Xela-DAB, -DBB, and -DCB genes is consistent with our previous observations, which suggested that the MHC of the tetraploid frog X. laevis is diploidized at the genomic level and contains three class II beta chain genes per haplotype that cross-hybridize to one another under reduced stringency conditions.

Amino Acid Sequence↗

Evaluation of bone loss and the serum markers of bone metabolism in patients with hyperparathyroidism.

Bone loss and the serum markers of bone metabolism were studied in 22 patients with primary hyperparathyroidism and 108 patients with renal hyperparathyroidism. The parameters of bone loss were bone mineral density in the distal radius and lumbar vertebrae, measured by dual energy X-ray absorptiometry, and bone mass index (sigma GS/D) and the metacarpal index, in the second metacarpal bone, measured by the digital image processing method. Alkaline phosphatase (AIP), intact osteocalcin (OC), and the carboxyterminal propeptide of type I procollagen (PICP) were measured as serum markers of bone formation, while tartrate-resistant acid phosphatase (TRACP) and the carboxyterminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) were measured as serum markers of bone resorption. Bone loss and elevated markers of bone metabolism were observed both in patients with skeletal symptoms and in those without. Furthermore, the decrease in the cortical bone mass was more predominant than that of the trabecular bone. As markers of bone formation, AIP and OC seemed to be more sensitive than PICP, and as markers of bone resorption, ICTP appeared to be more sensitive than TRACP. Thus, a close correlation was observed between bone loss and the markers of bone formation and resorption.

Acid Phosphatase↗

Familial non-multiple endocrine neoplasia medullary thyroid carcinoma: report of a case confirming a new clinical entity in Japan.

Most hereditary medullary thyroid carcinomas (MTC) occur in association with multiple endocrine neoplasia (MEN) type 2 syndromes. Since Farndon et al. reported two kindreds, that is collections of relatives, with familial non-MEN MTC in 1986, only five kindreds with this disorder have been reported in the English literature. In this paper, we describe a rare Japanese kindred with familial non-MEN MTC, confirming the existence of this distinct clinical entity in Japan. A 42-year-old woman underwent a left hemithyroidectomy with modified neck dissection (MND) under a diagnosis of sporadic MTC at 28 years of age. She developed lymph node metastasis in the right neck region 7 years after the initial surgery, and underwent MND and right hemithyroidectomy. Although no findings of MTC were histologically confirmed in the resected right thyroid lobe, C-cell hyperplasia was observed. Hereditary MTC was strongly suspected, but we could not confirm specific manifestations associated with MEN type 2 in any family members. However, 7 years later, a paternal aunt and cousin were diagnosed with MTC. Other family members were evaluated by ultrasonography and calcium-pentagastrin provocation testing, and three additional patients with MTC across two generations were found. None of these patients had any extrathyroidal manifestations associated with MEN type 2, and the entity of familial non-MEN MTC was confirmed.

Adult↗

Clinical efficacy of lansoprazole in eradication of Helicobacter pylori.

A randomized, single-blind study was designed to assess the effect of lansoprazole alone and lansoprazole plus amoxicillin on the healing and eradication rates in Helicobacter pylori-associated peptic ulcer disease. Seventy-nine patients with gastric ulcers and 54 patients with duodenal ulcers were randomly assigned to two treatment groups. Group 1 received lansoprazole 30 mg daily for 8 weeks for gastric ulcers or 6 weeks for duodenal ulcers. Group 2 received the group 1 regimen plus amoxicillin 2 g daily for 2 weeks. Healing rates at 8 weeks for the gastric ulcer patients were 92 and 84% in groups 1 and 2, respectively (p = not significant). Healing rates at 6 weeks for duodenal ulcers were 96% in group 1 and 100% in group 2 (p = not significant). The eradication rates of H. pylori for gastric ulcer patients were 21 and 54% in groups 1 and 2, respectively (p < 0.05). The H. pylori eradication rates for duodenal ulcer patients were 5 and 73% in groups 1 and 2, respectively (p < 0.001). The H. pylori eradication rates in group 2 were significantly higher than in group 1. Lansoprazole was effective for eradicating H. pylori in this study.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Analysis of naturally processed human histocompatibility leukocyte antigen class I-bound peptides from hepatocellular carcinoma tissues in vivo.

Naturally processed self-peptides bound to human histocompatibility leukocyte antigens (HLA) class I molecules of human hepatocellular carcinoma tissues (HLA-A2.1, -B44, -B13) in vivo were isolated for sequence analysis. Acid-eluted peptides were subjected to reversed-phase high-performance liquid chromatographic separation and single-fraction sequencing was performed by Edman degradation. The peptides were found to be octamers or nonamers and they were derived from the processing of intracellular proteins. Three independent sequences were obtained from HLA-A2.1 molecules. One of the peptides showed sequence homology to the hepatitis B virus (HBV) pre-S protein, one to aldehyde dehydrogenase, and the other to no known protein. Two independent sequences were obtained from HLA-B44, B13 molecules: one showed sequence homology to the human c-abl protein, the other showed no homology to any known protein. A synthetic biotinylated peptide based on the HBV pre-S peptide sequence was confirmed to bind to HLA-A2.1 gene-transfected L cells. These data suggested that peptides potentially recognized by cytotoxic T cells can bind to HLA class I molecules on tumor cells in vivo.

Amino Acid Sequence↗

A tobacco soluble protoporphyrinogen-oxidizing enzyme similar to plant peroxidases in their amino acid sequences and immunochemical reactivity.

Partial amino acid sequences of a soluble protoporphyrinogen-oxidizing enzyme (PPO) purified from tobacco cultured cells were identified. The sequences of two regions of the soluble PPO corresponded to the acid/base catalysis and heme binding regions of plant peroxidases. Anti-soluble PPO IgG cross-reacted with these plant peroxidases. Thus, the soluble PPO seems to be a kind of peroxidase.

Amino Acid Sequence↗

[Detection and localization of enlarged parathyroid glands in patients with hyperparathyroidism using 99mTc-methoxyisobutylisonitrile (MIBI): a study of subtraction scintigraphy with 99mTc-pertechnetate].

In this study we investigated the detectability of abnormal parathyroid gland(s) by 99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy in patients with hyperparathyroidism. The subjects were 6 patients with primary hyperparathyroidism (PHP) with a single adenoma and 13 patients with renal hyperparathyroidism (RHP) on chronic maintenance hemodialysis. The imaging data of 99mTc-pertechnetate were subtracted from those of 99mTc-MIBI (MIBI-Tc), and number and location of the positive images on scintigrams were compared with those obtained by conventional scintigraphy using 201Tl-Cl and 99mTc-pertechnetate (Tl-Tc). All of the patients underwent surgery, and the number and location of the abnormal parathyroid glands were confirmed. The number of resected parathyroid glands were 6 in PHP and 52 in RHP. The detectability of MIBI-Tc was 83.3% in PHP and 51.9% in RHP, while that of Tl-Tc was 100% and 44.2%, respectively. Although no statistically significant difference in the detectability was found between MIBI-Tc and Tl-Tc, the number of false positives with MIBI-Tc was less than that with Tl-Tc. The detectability of MIBI-Tc depended on the size of the parathyroid gland. The maximal diameter and weight of the smallest parathyroid gland detected were 15 mm and 290 mg in PHP, and 9 mm and 50 mg in RHP. The existence of the thyroid gland did not reduce the detectability of MIBI-Tc. In conclusion, MIBI-Tc was clinically very useful for the detection of abnormal parathyroid glands in patients with hyperparathyroidism.

Adult↗

[Analysis of naturally processed peptides bound to HLA-DR4, DR53 (DRB1*0405, DRB4*0101)].

We have isolated peptides bound to HLA-DR4, DR53 molecules obtained from HLA homozygous cell line cells, EBV-Wa (DRB1*0405, DRB4*0101), and determined amino acid sequences of the peptides. Amino acid sequences of 19 peptides were obtained and identified as peptide fragments of known proteins. Of those, macrophage migration inhibitory factor (MIF), beta 2 microglobulin (beta 2m), pyruvate kinase M2 (PKM2) and cathepsin C are considered to be endogenously derived, while transferrin and apolipoprotein B-100 are exogenous proteins. Peptides corresponding to each protein have a shared sequence with amino terminal or carboxy terminal protrusions. Based on the core sequences, putative DR4, DR53-binding motifs were suggested as Y----T/V--D or Y----T--D.

Amino Acid Sequence↗

[Bone mineral quantifying of methods in hyperparathyroidism].

Bone mineral densities (BMDs) in both cortical and trabecular bone decrease in primary hyperparathyroidism (PHP) and renal hyperparathyroidism (RHP). Bone mineral parameters in the second metacarpal bone were studied by digital image processing method (DIP). Lumbar BMD (L-BMD) and mid-radial BMD (R-BMD) were measured by dual energy X-ray absorptiometry (DXA). All indexes of bone mass at all measured sites in both PHP and RHP were significantly lower than normal those in controls. The decrease in appendicular BMD was more remarkable than that in LBMD. After parathyroidectomy (PTX), all indexes of bone mass with the exception of the MCI increase especially, in L-BMD. This discrepancy in dicates that PTH affects cortical bone and trabecular bone in dependently. Mild and moderate oversecretion of PTH has an anabolic effect, while a high of PTH has a catabolic effect on trabecular bone. The quantification of bone minerals is useful in follow-up studies and evaluation of the therapeutical response in hyperparathyroidism.

Absorptiometry, Photon↗

[Clinical prognosis of moderate restenosis after percutaneous transluminal coronary angioplasty].

Follow-up angiography after percutaneous transluminal coronary angioplasty (PTCA) often demonstrates "moderate" angiographic restenosis, but the need for subsequent revascularization is difficult to determine. We examined the clinical outcome of patients with moderate angiographic restenosis after PTCA. Follow-up angiography performed in 96 patients within 4 months showed light restenosis (LR:stenosis < 40%) in 52 patients, moderate restenosis (MR:40-70%) in 21, and severe restenosis (SR: > 70%) in 23. One of 21 patients with MR underwent repeat PTCA after a positive exercise test. The remaining 20 patients with MR were compared with 52 with LR (follow-up: 12-18 months). Five patients with MR underwent repeat PTCA for recurrence of angina in the follow-up period. Log rank analysis of the Kaplan-Meier estimates for event-free survival (death, myocardial infarction CABG, re-PTCA) showed the outcome was significantly worse for MR patients. However, 14 MR patients who had no cardiac event demonstrated regression of stenosis at 1-year follow-up angiography (58.2% to 45.4%). Moderate restenosis at angiographic follow-up was observed in 30% of all PTCA patients. Moderate restenosis patients have a worse prognosis than light restenosis patients. Adequate follow-up management is mandatory for moderate restenosis patients.

Aged↗