Search PubMed⌕ Search

Biomedical subjects

A Nagata

Publications and source records attributed to A Nagata.

At least 73 records · Page 4Linked to original sources
PubMed1996

Refractory thrombocytopenia with chromosome 11q23 abnormality.

Although cytopenia is a common manifestation of myelodysplastic syndrome (MDS), isolated thrombocytopenia is rare. The term "refractory thrombocytopenia" (RTC) has been proposed as a counterpart of refractory anemia. We describe here a case of RTC associated with chromosome abnormality on 11q23. A 59-year-old man was admitted because of severe thrombocytopenia. A bone marrow examination revealed an increased number of micromegakaryocytes and the absence of normal-sized megakaryocytes without obvious dysplasia in either the myeloid or the erythroid lineage. A remarkable increase of GPIIb/IIIa (CD41a)-positive precursor cells in the bone marrow was observed. Cytogenetic examination detected the chromosome abnormality, an addition on chromosome 11q23. Translocation of the HRX gene was not detectable by Southern blot analysis. The diagnostic problems of isolated thrombocytopenia and possible participation of gene(s) on chromosome 11q23 in megakaryocytopoiesis as well as early hematopoiesis are discussed.

Biopsy, Needle↗
PubMed1996

Two cases of severe bronchiectasis successfully treated with a prolonged course of trimethoprim/sulfamethoxazole.

Two patients with severe bronchiectasis, one patient without other disease and the other with hyper IgE syndrome, were successfully treated with long-term therapy with low doses of trimethoprim and sulfamethoxazole (TMP-SMZ). Recurrent respiratory infections with productive cough and high fever were resistant to various antibiotics and often disturbed the patients' activities in daily life. However, they showed marked improvement following TMP-SMZ therapy, which was started for methicillin-resistant Staphylococcus aureus (MRSA) infection. MRSA disappeared some months later, but Pseudomonas aeruginosa appeared again in the sputum. Both patients, however, have remained free from symptoms for over one year.

Adult↗
PubMed1996

[Amyloidosis secondary to bronchiectasis].

A 77-year-old woman was hospitalized repeatly due to frequent hemoptysis and production of bloodly sputum for several years. Bronchography in 1989 revealed bronchiectasis. She had complained of abdominal pain and diarrhea since 1991, and her urine was first positive for protein in 1992. She was admitted to our hospital in October 1992 because of edema, anemia, and hypoproteinemia. Despite treatment, renal dysfunction and the gastrointestinal disorder progressed and she died in January 1993. An autopsy revealed diffuse depositions of amyloid in many organs, especially in the kidney and the gastrointestinal tract. This amyloid protein was identified as AA protein, which was suggestive of secondary amyloidosis. Bronchiectasis appears to have been the disease underlying this patient's amyloidosis.

Aged↗
PubMed1996

Autoimmune chronic pancreatitis simulating pancreatic lymphoma.

A 51-yr-old man, who presented with diabetes mellitus, abdominal pain, inguinal lymphadenopathy, and diffuse enlargement of the whole pancreas on ultrasonography, was at first thought to have pancreatic lymphoma. Chemotherapy including steroid was carried out successfully, although the definitive diagnosis of lymphoma was not made. However, on follow-up, we realized that both laboratory findings, such as hyperglobulinemia and autoantibody-positive results, and radiographic features in this case were very similar to those of a case of autoimmune pancreatitis recently reported by Yoshida et al. (Dig Dis Sci 1995;40:1561-8). When the disease recurred, therefore, treatment with steroid alone was performed with an excellent result. We report a case of autoimmune pancreatitis simulating primary pancreatic lymphoma.

Autoimmune Diseases↗
PubMed1996

[A case of paranasal sinusitis-cavernous sinusitis with ophthalmoplegia externa].

A 15-year-old man was admitted because of diplopia and bilateral ptosis which occurred a few days after initial clinical signs, such as fever up, nausea, vomiting and headache. His pupils were anisocoric (Rt. phi 3.5 mm < Lt. phi 6.0 mm). In his left eye, light reflex was absent and its movements were limited in all directions. Brain MRI revealed the findings of paranasal sinusitis in bilateral ethmoidal and sphenoidal sinuses and swelling of bilateral cavernous sinus. Combination of intravenous antibiotic therapy and drainage improved his clinical symptoms and MRI findings. It was diagnosed as the inflammation originated in the sphenoid and ethmoid sinuses, which extended to the cavernous sinus and then involved III, IV, and VI cranial nerves. In conclusion, MRI was very useful to detect the cavernous sinusitis secondary to sphenoidal sinusitis.

Adolescent↗
PubMed1996

[Awareness of health and welfare planning for elderly and methods to increase awareness: based on social marketing].

To clarify the socio-psychological factors affecting awareness of health and welfare planning for the elderly, a survey of community residents was performed in the Tokyo metropolitan area. The results obtained were as follows: 1. There were three factors which affected awareness concern about health and welfare services for the elderly as a social issue: concern about the local community; and concern about the local government. 2. Two other factors which did not affect the level of awareness were: anxiety about the health and welfare services for the elderly as a personal issue; and having personal experience of nursing care. From these results, a method to increase awareness was studied based on social marketing methods. Two primary target groups for increasing awareness were identified. One target was people who have the socio-psychological factors described above. Another target was people who have the potential need for health and welfare services but who were not aware of it. That is, they have relatively high anxiety about health and welfare services for the elderly as a personal issue and have personally experienced nursing care. The method of approach for these targets were studied. For the first group, the amount of the information available seemed to be important because these persons are ready to recognize the need for planning. Therefore, efficient information channels should be selected. For the second group, approaches that generate greater consumer participation by presenting this as an efficient method for solution of the problem should be adopted.

Adult↗
PubMed1995

The POU domain transcription factor Brn-2 is required for the determination of specific neuronal lineages in the hypothalamus of the mouse.

We generated mice carrying a loss-of-function mutation in Brn-2, a gene encoding a nervous system specific POU transcription factor, by gene targeting in embryonic stem cells. In homozygous mutant embryos, migratory precursor cells for neurons of the paraventricular nuclei (PVN) and the supraoptic nuclei (SO) of the hypothalamus die at approximately E12.5. All homozygous mutants suffered mortality within 10 days after birth, possibly because of a complete deficiency of these neurons in the hypothalamus. Although neither developmental nor histological abnormalities were observed in heterozygous mice, the levels of expression of vasopressin and oxytocin in the hypothalamus of these animals were half these of wild-type mice. These results strongly suggest that Brn-2 plays an essential role in the determination and development of the PVN and SO neuronal lineages in the hypothalamus.

Animals↗
PubMed1995

Characterization of a specific monoclonal antibody 9F5-3a and the development of assay system for oxidized HDL.

We obtained a monoclonal antibody 9F5-3a against oxidative low-density lipoprotein (LDL) modified with CuSO4 and established a sandwich ELISA for detection of oxidized high-density lipoprotein (oxHDL). The 9F5-3a was reacted strongly with oxHDL and to a lesser degree with oxLDL and LDL. In contrast, little or no reactivity was found with HDL. When the generation of oxHDL was limited by the addition of alpha-tocopherol and catalase, reactivity to 9F5-3a was reduced. Incubation of oxHDL with excess lyso-phosphatidylcholine (lyso-PC) also reduced immunoreactivity, but not by only lyso-PC. These results suggested that the epitope is possibly associated with oxHDL-linked lyso-PC induced mainly by the hydroxyl radical.

Animals↗
PubMed1995

Neurite outgrowth of murine cerebellar granule cells can be enhanced by aniracetam with or without alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA).

To assess the neurotrophic effects of a nootropic drug, aniracetam, we studied neurite extension of mouse cerebellar granule cells in culture with low or with high K+ under different combinations of drugs and then immunohistochemically stained the cells with an antibody against L1, a neural cell adhesion molecule on cerebellar granule cells. Quantitative analyses using parameters of the total neurite length, maximal neurite length and number of branches disclosed that aniracetam, in the presence of high K+ and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA), significantly enhanced neurite extension of cultured granule neurons. Aniracetam alone also stimulated neurite extension of cerebellar granule cells at a longer period of culture with low K+ showing a bell-shaped dose response curve with maximal effects at 10 microM. Aniracetam may influence remodeling of the neural network after injury.

Animals↗
PubMed1995

M-wave modulation at relative levels of maximal voluntary contraction.

Frequency (mean and median power frequency, f and fm) and amplitude (average rectified and root mean square values, ARV and rms), parameters of the M-wave, and the dorsiflexor force parameters of the anterior tibial muscles were measured in seven healthy human subjects. Intermittent, voluntary contractions at relative intensities (40%, 60%, and 80%) of maximal voluntary contraction (MVC) were performed in conjunction with electrical stimulation. The M-wave parameter changes were measured over the course of the isometric contractions. At higher force levels, M-wave potentiation was observed as increases in both ARV and rms. The ARV augmentation attained levels as high as 206.1 (SD 7.4)% of resting values after both initial and final contractions of 80% MVC, reaching statistical significance (P < 0.01). The f and fm failed to show a significant difference at any level of contraction. It was surmised that potentiation of the M-wave was the result of an increased contribution of muscle fibre type IIb recruited during higher contraction levels, reflecting the change to larger, deeper innervating motoneurons as the intensity of contraction, as a percentage of MVC, rose. Recruitment of type IIb fibres, which have been reported to have a higher energy potential and frequency content, were thought to reflect changes in the local excitability threshold of some motor units as the force intensity increased during the intermittent voluntary contractions. It is suggested that the M-wave elicited after contractions has the potential to reflect, to some extent, motor unit recruitment changes resulting from the preceding contractions, and that through comparisons of M-wave amplitude parameters contributions of varying fibre types over the course of a contraction may be indicated.

Adult↗
PubMed1995

Sea urchin egg tropomyosin isoforms with muscle-type and nonmuscle-type antigenicities.

Egg tropomyosins were prepared from four sea urchin species, Stronglyocentrotus intermedius, Anthocidaris crassispina, Hemicentrotus pulcherrimus and Pseudocentrotus depressus, and their molecular heterogeneity was investigated by electrophoresis and immunoblotting. The molecular heterogeneity of egg tropomyosins was species-specific, and two to four kinds of tropomyosin isoforms were detected, the apparent molecular weights of which were 29,000-32,000. The egg tropomyosin isoforms could be classified into two groups with muscle- and nonmuscle-type antigenicities in each species. No obvious difference in their cytological localization was observed immunocytochemically in S. intermedius and H. pulcherrimus.

Actins↗
PubMed1994

Dnacin A1 and dnacin B1 are antitumor antibiotics that inhibit cdc25B phosphatase activity.

The p80cdc25 protein is a protein phosphatase directly involved in p34cdc2 protein kinase activation by dephosphorylation. The cdc25B gene is one of three human cdc25 homologs which can complement the temperature-sensitive cdc25 mutation of Schizosaccharomyces pombe, and is expressed a high levels in human cell lines, particularly in some cancer cells. A fusion protein of glutathione-S-transferase (GST) and the catalytic domain of cdc25B protein was constructed and found to retain phosphatase activity in the manner of a p80cdc25 phosphatase by using a chromogenic substrate, p-nitrophenylphosphate. Two benzoquinoid antitumor compounds, dnacin A1 and dnacin B1, inhibited phosphatase activity in a non-competitive manner.

Antibiotics, Antineoplastic↗
PubMed1994

Carbohydrate-mediated recognition of a circulating placental alkaline phosphatase-immunoglobulin M complex.

We detected an abnormal alkaline phosphatase (AP) electrophoretically in the serum of a patient with rheumatoid arthritis, who had a macromolecular AP linked with immunoglobulin M (IgM) bearing a kappa light chain. The IgM isolated from the AP-IgM complex in the patient's serum reacted apparently with all of the AP isozymes tested, i.e. those originating in the liver, bone, intestine and placenta, but the alpha-mannosidase-treated IgM from the patient's serum bound to placental AP (PAP) alone. This suggests that untreated IgM recognizes multivalent epitopes of the AP and that the complex of AP with alpha-mannosidase-treated IgM is a specific antibody-antigen complex. In order to investigate further the multivalent binding capacity for the PAP-untreated IgM complex, we prepared a monoclonal antibody (MoAb) against PAP and identified it as an IgM with a kappa light chain. The binding affinities and their circulating half-lives of the synthetic complexes of PAP and respective MoAbs were examined with and without treatment with several glycosidases. The untreated MoAb bearing IgM had binding affinity for all of the AP isozymes tested, while alpha-mannosidase-treated IgM attached only to PAP, the same as the IgM isolated from the PAP-IgM complex in the patient's serum. The circulating clearance of the PAP-IgM complex in rabbits was faster than either component alone. In addition, the PAP-IgM complex treated with alpha-mannosidase was found to have the shortest half-life of all the complexes of PAP and Igs treated with the several glycosidases tested. These results suggest that the formation of the PAP-IgM complex as an enzyme-linked antibody and the clearance of the complex in vivo are dependent on the sugar moieties of the Igs.

Adult↗