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Biomedical subjects

N Nagata

Publications and source records attributed to N Nagata.

At least 19 recordsLinked to original sources

Hypoglycemia associated with localized fibrous mesothelioma of the pleura.

Hypoglycemia is known to be a rare consequence of non-islet cell tumors. A patient having severe, episodic hypoglycemia was found to have a large mass occupying the right hemithorax. The hypoglycemia resolved immediately after surgical removal of the tumor. Histologic examination of the tumor revealed localized fibrous mesothelioma.

Female

[A case of pulmonary hyalinizing granuloma with its occupational history of dust exposure].

Multiple pulmonary nodules were found in a patient who had an occupational history of coal mining for eleven years and road construction for fifteen years. An open lung biopsy was performed, because nodules had increased in size compared to previous ones and a trasbronchial biopsy was not diagnostic. The nodules were composed of dense concentric lamellar collagenous structures with a serpentine pattern surrounded by an infiltration of histiocytes, lymphocytes and plasma cells with Russel bodies. These findings are compatible with pulmonary hyalinizing granuloma (PHG) named by Liebow A. A. The etiopathogenetic mechanism and the difference between PHG and silicotic nodule is discussed.

Aged

Leucocytosis as a marker of organ damage induced by chronic strenuous physical exercise.

The effects of strenuous physical exercise on the serial changes in the haematological, biochemical and hormonal markers were investigated. A group of 14 soldiers, aged 24-36 years, took part in a military training course for about 13 weeks. After severe exercise stress, an increase (90%) in the number of peripheral blood leucocytes was observed. The degree of leucocytosis showed a close correlation with the values of some serum parameters, such as concentrations of aspartate aminotransferase (AST; r = 0.747), lactate dehydrogenase (LD; r = 0.748), blood urea nitrogen (r = 0.756), creatine kinase (CK; r = 0.637), manganese-superoxide dismutase (Mn-SOD; r = 0.508), alanine aminotransferase (ALT; r = 0.542) and uric acid (r = 0.538), and concentrations of urinary parameters, such as vanilmandelic acid (r = 0.429) and free cortisol (r = 0.437). The subjects showing prominent leucocytosis over 9500 cells.microliters-1 exhibited a lower concentration of serum cholinesterase than those who showed milder leucocytosis. The serum Mn-SOD concentration was closely correlated with the serial changes in serum concentrations of AST, ALT, LD and CK, indicating exercise-induced muscle and liver damage. The change in peripheral leucocyte number was assumed to be diagnostically informative and may be a prognostic marker, reflecting organ damage and restoration after strenuous physical exercise.

Adult

Inhibition by actinomycin D of neurogenic mouse ear oedema.

We have investigated the effects of actinomycin D on mouse ear oedema induced by capsaicin, neuropeptides, and established inflammatory mediators. Actinomycin D (0.5 mg/kg, i.v.) significantly (P < 0.01) inhibited ear oedema induced by topical application of capsaicin, while adriamycin (6.0 mg/kg, i.v.) and cycloheximide (6.0 mg/kg, i.v.) had no effect on oedema. The ear oedema induced by intradermal injection of neuropeptides such as mammalian tachykinins, calcitonin gene-related peptide (CGRP), and vasoactive intestinal peptide (VIP), was markedly (P < 0.05, P < 0.01 or P < 0.001) suppressed by actinomycin D. The drug was also effective (P < 0.01 or P < 0.001) in inhibiting bradykinin (BK)- and compound 48/80-induced ear oedema, but did not inhibit oedema induced by histamine, 5-HT, leukotriene C4 (LTC4), and platelet activating factor (PAF) at a dose of 1 mg/kg. In mast cell-deficient W/WV mice, actinomycin D (1.0 mg/kg, i.v.) failed to inhibit substance P (SP)-induced ear oedema whereas spantide (0.5 mg/kg, i.v.) was an effective (P < 0.01) inhibitor of oedema formation. Furthermore, actinomycin D (10-100 microM) dose-dependently prevented histamine release from rat peritoneal mast cells evoked by SP, compound 48/80, and the ionophore A23182, respectively. These results strongly suggest that an inhibitory effect of actinomycin D on neurogenic inflammation is due primarily to the prevention of mast cell activation mediated by neuropeptides, rather than an interaction with DNA or receptors of neuropeptides.

Animals

Bridging annuloplasty for common atrioventricular valve regurgitation.

Progressive common atrioventricular valve regurgitation is a serious condition in children with a univentricular heart. We developed a repair procedure that consists of using a Teflon tape bridge and total circular annuloplasty to divide the common atrioventricular valve into two atrioventricular valves. This procedure was performed in 2 infants, and the results were satisfactory. Details of the technique are described.

Child, Preschool

Non-cushingoid Cushing's syndrome due to adrenocorticotropic hormone-independent bilateral adrenocortical macronodular hyperplasia.

This case report describes a 68-year-old man with Cushing's syndrome due to adrenocorticotropic hormone (ACTH)-independent bilateral adrenocortical macronodular hyperplasia (AIMAH). He was referred to our hospital for evaluation of bilateral enlargement of the adrenal glands found incidentally by computed tomography (CT). He had a ten-year history of hypertension. Although he was normokalemic and did not show Cushingoid features, the diagnosis of ACTH-independent Cushing's syndrome was established by endocrinological examinations. His plasma cortisol showed no diurnal rhythm and was unsuppressible by high-dose (8 mg/day) dexamethasone. Plasma ACTH was undetectable and did not respond to corticotropin-releasing hormone. Excised adrenal glands were markedly enlarged (right 28 g and left 64 g). Macroscopic appearance of the glands showed multiple yellowish nodules typical for AIMAH; microscopic findings were also compatible with AIMAH. The present case indicates that patients with AIMAH sometimes do not show typical Cushingoid features and therefore AIMAH can be found incidentally from ultrasound or CT examination of the abdomen.

Adrenal Glands

Magnetic resonance imaging of multiple brain abscesses of the bilateral basal ganglia.

A 64-year-old woman developed multiple brain abscesses of the basal ganglia associated with Klebsiella pneumoniae septicemia. Magnetic resonance (MR) images showed three different stages of the brain abscesses. The images of early cerebritis of this site mimicked lacunar infarctions or dilated Virchow-Robin spaces. The differentiation of the brain abscess from lacunae and dilated Virchow-Robin spaces is discussed, together with the evolution of the brain abscesses on MR images.

Basal Ganglia

[An autopsy case of immature teratoma with choriocarcinoma in the mediastinum].

The autopsy of a 28-year-old Japanese male patient, which revealed immature teratoma combined with choriocarcinoma in the mediastinum, is presented. The tumor, which was removed after chemotherapy, was localized in the superior-anterior mediastinum. Chemotherapy was performed several times after operation. However, HCG increased again, and a roentgenogram revealed metastatic shadows in both lungs. The metastatic tumors in the lungs showed only the choriocarcinoma.

Adult

Transcutaneous blood glucose monitoring system based on an ISFET glucose sensor and studies on diabetic patients.

A transcutaneous blood glucose monitoring system consists of an ion-sensitive field-effect transistor (ISFET) glucose sensor unit and a suction effusion fluid (SEF) collecting unit. The SEF is directly collected by a weak suction (400 mmHg absolute pressure) through the skin from which the corneum layer of the epidermis has been previously removed. An ISFET glucose sensor unit is able to measure glucose concentrations in a microliter order sampling volume. The system was applied to three diabetic patients during a 75 g oral glucose tolerance test for monitoring blood glucose levels. During the experiments, glucose changes in the SEF followed actual blood glucose levels with 10 min delays. Results suggest the feasibility of utilizing quasi-continuous, transcutaneous blood glucose monitoring for individual patients with various diabetic histories or diabetic complications.

Aged

[Spontaneous regression in a case of primary pulmonary lymphoma with Sjögren's syndrome].

A 62-year-old asymptomatic woman had a nodular shadow approximately 3 cm in diameter in the middle lung field on chest roentgenogram. The shadow gradually grew over 1.5 years. She was then admitted to our hospital for evaluation of the abnormal shadow. Transbronchial biopsy specimens showed a diffuse, small, lymphoid infiltrate with predominance of B-cells. These findings suggested neoplastic proliferation. Further examinations revealed the presence of Sjögren's syndrome. Four months later, she was readmitted for surgical resection. Chest roentgenogram on the second admission disclosed that the mass shadow had shrunk slightly. Histopathological examination of the resected specimen led to the diagnosis of malignant lymphoma, diffuse small cell type (IgG kappa type). Gene analysis revealed the presence of heavy chain gene rearrangements, which confirmed the diagnosis of B-cell lymphoma. In this case, no contraction or necrosis of the lesion was observed, and the change in the shadow size was probably due to partial or transient spontaneous regression.

Female

[Autopsy of a patient with rheumatic fever, who initially presented with acute respiratory failure].

A 59-year-old man was admitted to the hospital because of dyspnea, fever, and general erythema. He had hypoxemia on admission. Chest X-ray film showed diffuse reticulonodular shadows in both lungs. Chest CT showed a diffuse increase in density, predominantly in both lower lobes. The respiratory failure had rapidly progressed, and the patient died only 40 hours after admission. Autopsy revealed diffuse alveolar damage in the lung, and Aschoff's bodies in the cardiac muscle. Aschoff's bodies are specific for rheumatic fever, and consist of Aschoff's cells with owl-eye-like or caterpillar-like nuclei. We diagnosed this patient's condition as rheumatic fever because of the presence of Aschoff's bodies. Rheumatic fever is generally seen as a disease of younger people, and these patients rarely present with respiratory signs, but this case shows that we have to recognize the possibility of rheumatic fever in adults with respiratory signs and skin lesions.

Acute Disease

[A case of sarcoidosis with advanced cystic and fibrotic changes in a young patient].

A 29-year-old man was referred to our hospital because of exertional dyspnea and progressive eruption on the buttocks and the lower extremities. Chest roentgenograms and computed tomograms taken at that time revealed diffuse fibrotic changes accompanied by multiple cavities and bullae in the lungs. There were no signs of mediastinal or hilar lymphadenopathy. A chest roentgenogram taken 7 years before admission showed no abnormalities. Serum ACE and lysozyme levels were high: 29.9 IU/l and 14.1 micrograms/ml, respectively. 67Ga scintigraphy showed diffuse uptake in both lung fields. The PPD skin test was negative, and repeated sputum smears and cultures were negative for pyogenic bacteria and acid-fast bacilli. Examination of transbronchial lung biopsy and skin biopsy specimens confirmed the diagnosis--they showed noncaseating epithelioid granulomas with giant cells and a negative reaction of the stain to acid-fast bacilli, which are compatible with sarcoidosis. The patient was given 30 mg/d of prednisone orally. The dyspnea and eruption were clearly alleviated, although there was little roentgenographic regression of cystic or fibrotic changes. There have been only a few reports of cystic and fibrotic changes early in the course of sarcoidosis. The cystic lesions in this case were probably secondary pulmonary cavities caused by the contracting and obstructive changes related to pulmonary fibrosis.

Adult

[Factors regulating parathyroid hormone and the mechanism of signal transduction].

The secretion of parathyroid hormone (PTH) is influenced by various factors, but extracellular calcium concentration ([Ca2+]e) is the sole factor established to be the physiological regulator. [Ca2+]e acts on Ca2+ sensing receptor recently cloned, and elevates intracellular calcium ([Ca2+]i) and inositol trisphosphate. Although the changes in cAMP level and C-kinase activity also have been demonstrated, the mediator directly operating secretory mechanism of PTH has not been defined. Recently, the activity of chromogranin A-related peptides to modulate PTH secretion was found and their role as the autocrine-paracrine regulator of PTH secretion has been proposed.

Calcium

Structural analysis of proteoglycan macrophage colony-stimulating factor.

Proteoglycan macrophage colony-stimulating factor (PG-M-CSF) was recently reported as a high molecular type of macrophage colony-stimulating factor (M-CSF). We analyzed its structure by determining the expression of mutant M-CSF cDNA in Chinese hamster ovary cells. PG-M-CSF contained two types of molecules, a homodimeric 150-200-kDa subunit and a heterodimeric form of a 43-kDa subunit and the 150-200-kDa subunit. The 150-200-kDa subunit carries a chondroitin sulfate chain, and its amino-terminal amino acid sequence was identical to that of the 43-kDa subunit, which is known to form the conventional M-CSF molecule (85-kDa M-CSF). The results obtained with the carboxyl-terminal deleted mutants showed that the PG-M-CSF-specific 150-200-kDa subunit had a large part of the precursor sequence at its carboxyl terminus removed in the 43-kDa subunit by proteolytic processing. The expression of mutagenized cDNA, in which Arg220 was replaced by an alanine residue, resulted in the disappearance of the 43-kDa subunit but not that of the 150-200-kDa subunit, indicating that Arg220-Pro-Pro-Arg is essential to process PG-M-CSF to 85-kDa M-CSF. Truncated mutation analysis showed that the carboxyl terminus of the 150-200-kDa subunit lay downstream of Arg412. We also showed that the chondroitin sulfate binding site in the 150-200-kDa subunit was Ser277, since conversion of Ser277 to the alanine residue resulted in complete loss of the chondroitin sulfate substitution.

Amino Acid Sequence

Experimental carcinogenesis in the rat intestine induced by two different carcinogens--evaluation of carcinogenic action and its effect on ornithine decarboxylase activity.

Carcinogenesis in the rat intestine induced with 1,2-dimethylhydrazine (DMH), N-methyl-N-nitrosourea (MNU), and their combinatorial use was studied. Intestinal tumors, including both adenoma and adenocarcinoma, were induced in all the rats given the carcinogens. The tumor frequently occurred in the intestinal tract extending from the duodenum to the colon in the DMH treated group. In the MNU treated group, the tumor occurred in the colon, especially on the distal side. Distribution of tumors in the group treated with both carcinogens was similar to that seen in the MNU-treated group. Neither obvious macroscopic nor histological differences were observed between groups treated with these carcinogens. In addition, we investigated the effect of carcinogens on ornithine decarboxylase (ODC) activity in rat colon. Tumor tissues showed a remarkably high level of enzyme activity compared with the normal-appearing mucosa, and there was a correlation between the level of the ODC activity and the histological grade of malignancy. ODC activity in the normal-appearing mucosa of the carcinogens-treated rats was significantly higher than that of control rats, and the number of tumors per rat was correlated with the level of ODC activity. These results indicate that mucosal ODC may be a pertinent biological marker for local carcinogenic activity.

1,2-Dimethylhydrazine

Direct interaction of proteoglycan macrophage colony-stimulating factor and basic fibroblast growth factor.

The proteoglycan form of macrophage colony-stimulating factor (PG-M-CSF), but not M-CSF with a molecular weight of 85 kD (85-kD M-CSF), bound to immobilized basic fibroblast growth factor (bFGF), and, conversely, bFGF bound to immobilized PG-M-CSF, but not to the 85-kD M-CSF. PG-M-CSF has an additional amino acid sequence at its carboxyl terminus (part of a precursor sequence that is removed in 85-kD M-CSF by proteolytic processing) and it has one or two chondroitin sulfate glycosaminoglycan chains at the carboxyl terminus. Enzymatic removal of the chondroitin sulfate chain from PG-M-CSF had no effect on the binding between PG-M-CSF and bFGF. Ligand blotting analysis with radioiodinated bFGF showed that bFGF specifically bound to the polypeptide that corresponded to the carboxyl terminus of PG-M-CSF and was produced in Escherichia coli transfected with its gene. The exogeneous addition of heparan sulfate, which has strong affinity for bFGF, efficiently inhibited the binding between PG-M-CSF and bFGF. These results show that PG-M-CSF binds bFGF through its carboxyl terminal peptide and that the binding sites for PG-M-CSF and heparan sulfate on bFGF are located close together. PG-M-CSF also significantly reduced the mitogenic action of bFGF on Balb/c 3T3 mouse fibroblastic cells. Therefore, we conclude that PG-M-CSF not only binds bFGF, but also neutralizes the activity of the growth factor.

3T3 Cells

Dystrophin-related protein is found in the central nervous system of mice at various developmental stages, especially at the postsynaptic membrane.

Dystrophin deficiency is known to be the cause of X-linked Duchenne muscular dystrophy (DMD). A recently cloned B3-cDNA shares 80% homology with the C-terminus and actin-binding portion of dystrophin. This autosome-derived gene product is called dystrophin-related protein (DRP). DRP is known to exist in fetal muscles even in mdx mice, an animal model for X-linked DMD, but not in mature mouse muscles. We raised a polyclonal antibody against a B3-unique amino acid sequence (Ab-LDP) and investigated the existence and distribution of DRP in the central nervous system (CNS) tissues of mdx and normal control B10 mice at various stages of development using immunoblotting and immunohistochemical methods. The former shows that DRP exists in the CNS of both B10 and mdx mice, regardless of the developmental stage, with the exception that the 420 kDa DRP band of the 15-day fetus is faint. In immunohistochemical studies, the choroid plexus, some neurons, glial cels, pia mater, and blood vessels were stained with Ab-LDP. Staining intensity did not differ between B10 and mdx mice or between developmental stages except that the 15-day fetus stained only faintly. This is in contrast to the results obtained for muscles in which DRP localized to muscle membrane in embryo decreases and is assembled at the neuromuscular junction in adults. In addition, an electron microscopic study on the cerebral cortex from adult B10 mice was also performed and revealed Ab-LDP staining of the postsynaptic membrane of dendrite and the rough endoplasmic reticulum of neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence