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Biomedical subjects

A Nakajima

Publications and source records attributed to A Nakajima.

At least 73 records · Page 4Linked to original sources
PubMed2000

Protein-losing enteropathy associated with hypocomplementemia and anti-nuclear antibodies.

We report a case of protein-losing enteropathy associated with an autoimmune disorder, presumably systemic lupus erythematosus. Although typical manifestations of systemic lupus erythematosus were lacking, a high serum cholesterol level, a low serum complement level, positivity for anti-nuclear antibody, and positivity for anti-single-strand DNA antibody suggested an autoimmune mechanism as the cause of the condition. Although immunohistological examination of duodenal and ileal biopsy specimens failed to reveal deposits of immune complex or complement in the vessels, capillary hyperpermeability was suspected as the mechanism of the condition.

Adult↗
PubMed2000

Tacrolimus in corticosteroid-resistant ulcerative colitis.

We report a case of refractory ulcerative colitis treated with tacrolimus. The patient was a 73-year-old woman with a 45-year history of ulcerative colitis. An attack unresponsive to intravenous corticosteroid therapy occurred when she was age 73. Leukocytapheresis therapy was attempted, but was discontinued because of the patient's poor general condition. Cyclosporine A therapy brought about fair control of the disease. A liver injury that was suspected to be associated with this agent, however, occurred within 5 weeks of its initiation. At that time, the cyclosporine A was discontinued and azathioprine treatment was started. Within 6 weeks, signs of exacerbation of the ulcerative colitis became apparent. Tacrolimus administered at that time brought about remission of the disease, and the corticosteroid dose was then reduced. Tacrolimus, like cyclosporine A, appears to be effective for the treatment of attacks of ulcerative colitis.

Aged↗
PubMed2000

In vivo evaluation of hippocampal anti-oxidant ability of zonisamide in rats.

We evaluated the anti-oxidant property of zonisamide (ZNS) in the rat brain under freely moving conditions by means of in vivo microdialysis of two exogenous nitroxide radicals, 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (carbamoyl-PROXYL) and 3-methoxy carbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM). Time-dependent changes in the signal intensities of these exogenous nitroxide radicals obtained from the hippocampal perfusates were observed using an X-band ESR spectrometer at 20-min intervals. The ESR signal intensities of nitroxide radicals decreased exponentially in all animals, which indicates that their half-life could be used as a parameter to estimate the decay rate of nitroxide radicals. Nitroxide radicals lose their paramagnetism when exposed to reductants in a biological system. Thus, half-life reflects the in vivo reducing ability. Although the half-life of carbamoyl-PROXYL, which could not pass the blood-brain barrier (BBB), was not changed when compared with the controls, pre-treatment with ZNS significantly shortened the half-life of PCAM, which could pass through the BBB. These findings suggest that the ZNS-induced increase in reducing ability did not occur within the extracellular space, but rather mainly at the neural cell membrane. This study is the first in vivo evaluation of the reducing ability of ZNS in freely moving animals.

Animals↗
PubMed2000

A carcinoembryonic antigen family cDNA from mouse placenta encoding a protein with a rare domain composition.

The carcinoembryonic antigen (CEA) family comprises many members with pleiotropic functions. Among normal tissues, placenta is characterized by the abundant production of many different kinds of CEA-related proteins, which are apparently important for the maintenance of pregnancy. Using RNA differential display applied to mouse placentae at different gestational days, we have isolated a novel CEA-related cDNA designated as Ceacam11. Ceacam11 cDNA encodes 303 amino acids with a possible signal peptide and two immunoglobulin variable region-like domains. This domain composition is observed only in mouse Cea10/Ceacam10 among the many CEA family members thus far reported. The transcript of Ceacam11 was first detected in the placenta at 12.5 days post-coitus (dpc) and the level increased progressively towards 17.5 dpc. The expression of Ceacam11 appears to be reciprocal to that of Ceacam10, since the Ceacam10 transcripts were detected at 8.5 and 10.5 dpc, but not at 12.5 to 17.5 dpc. In situ hybridization showed that the expression of Ceacam11 was localized to the spongiotrophoblast of the placenta. Except for in the placenta, Ceacam11 transcripts were not detected in any adult tissues examined, including brain, lung, glandular stomach, small intestine, colon, liver, kidney and testis.

Amino Acid Sequence↗
PubMed2000

Elevations of group II phospholipase A2 concentrations in serum and amniotic fluid in association with preterm labor.

OBJECTIVE: The purpose of this study was to determine whether the elevation of secretory group II phospholipase A(2) concentration in the serum and amniotic fluid in preterm labor is associated with intrauterine inflammation. STUDY DESIGN: Serum and amniotic fluid were collected from women with preterm delivery (<37 weeks' gestation; n = 38) and term delivery (n = 20). Phospholipase activity was measured with a highly sensitive system that was based on reverse-phase high-performance liquid chromatographic separation of 9-anthracenylmethyl derivatives of fatty acids released by phospholipase A(2). The concentrations of immunoreactive isozymes (group I or II) of secretory phospholipase A(2) were assayed with a radioimmunoassay kit with a monoclonal antibody against human pancreatic phospholipase A(2) and splenic IIA phospholipase A(2). Localization of immunoreactive group II phospholipase A(2) in the amniotic membrane was determined by immunostaining visualized with the Vectastain ABC (Vector Laboratories, Inc, Burlingame, Calif) method. RESULTS: Enzymatic activities of phospholipase A(2) in the serum and amniotic fluid specimens obtained from patients in preterm labor with chorioamnionitis were significantly higher than those in specimens from patients in term labor. Significant elevations of phospholipase A(2) activities were observed in patients with preterm labor without histologically evident chorioamnionitis. The activity of phospholipase A(2) was clearly correlated with the concentration of the immunoreactive group II phospholipase A(2). Group II phospholipase A(2) was localized in amniotic cells obtained from patients with a pathologically determined diagnosis of chorioamnionitis. The predictive value for chorioamnionitis of the group II phospholipase A(2) concentration was relatively higher than the predictive values of the concentrations of C-reactive protein and interleukins 6 and 8. CONCLUSION: Significant elevations of group II phospholipase A(2) concentrations were detected in the serum and amniotic fluid of women with preterm labor. Group II phospholipase A(2) concentration may be a useful indicator for preterm labor, and phospholipid metabolism is certainly activated both in preterm labor and in apparent inflammatory diseases.

Amniotic Fluid↗
PubMed2000

Effect of sulbactam on anti-pseudomonal activity of beta-lactam antibiotics in cells producing various levels of the MexAB-OprM efflux pump and beta-lactamase.

The beta-lactamase inhibitor, sulbactam, was tested for beta-lactamase inhibitory activity in Pseudomonas aeruginosa cells producing various levels of both the MexAB-OprM efflux pump and beta-lactamase. We found that sulbactam lowered the MICs of cefoperazone and piperacillin by inhibiting the beta-lactamase 8-fold in the cell producing a constitutively high level of AmpC-type beta-lactamase and a wild-type level of MexAB-OprM pump compared with that without sulbactam. The MICs of cefoperazone and piperacillin in the cell producing a constitutively high level of both the efflux pump and beta-lactamase under the presence of sulbactam were 8 and 4 times, respectively, lower than that without sulbactam. The MICs of sulbactam in the cell producing a constitutively high and a wild-type level of the efflux pump were 16- and 8-fold higher, respectively, than that in the mutant lacking the efflux pump. We concluded that sulbactam exerts potent beta-lactamase inhibitory activity in the cell producing a high level of efflux pump, in spite of the fact that sulbactam serves as a substrate of the MexAB-OprM pump. Increasing amounts of sulbactam over the weight of beta-lactams further strengthen the effect of beta-lactam antibiotics.

Anti-Bacterial Agents↗
PubMed2000

Sp110 localizes to the PML-Sp100 nuclear body and may function as a nuclear hormone receptor transcriptional coactivator.

The nuclear body is a multiprotein complex that may have a role in the regulation of gene transcription. This structure is disrupted in a variety of human disorders including acute promyelocytic leukemia and viral infections, suggesting that alterations in the nuclear body may have an important role in the pathogenesis of these diseases. In this study, we identified a cDNA encoding a leukocyte-specific nuclear body component designated Sp110. The N-terminal portion of Sp110 was homologous to two previously characterized components of the nuclear body (Sp100 and Sp140). The C-terminal region of Sp110 was homologous to the transcription intermediary factor 1 (TIF1) family of proteins. High levels of Sp110 mRNA were detected in human peripheral blood leukocytes and spleen but not in other tissues. The levels of Sp110 mRNA and protein in the human promyelocytic leukemia cell line NB4 increased following treatment with all-trans retinoic acid (ATRA), and Sp110 localized to PML-Sp100 nuclear bodies in ATRA-treated NB4 cells. Because of the structural similarities between Sp110 and TIF1 proteins, the effect of Sp110 on gene transcription was examined. An Sp110 DNA-binding domain fusion protein activated transcription of a reporter gene in transfected mammalian cells. In addition, Sp110 produced a marked increase in ATRA-mediated expression of a reporter gene containing a retinoic acid response element. Taken together, the results of this study demonstrate that Sp110 is a member of the Sp100/Sp140 family of nuclear body components and that Sp110 may function as a nuclear hormone receptor transcriptional coactivator. The predominant expression of Sp110 in leukocytes and the enhanced expression of Sp110 in NB4 cells treated with ATRA raise the possibility that Sp110 has a role in inducing differentiation of myeloid cells.

Amino Acid Sequence↗
PubMed2000

Phytotoxicity of indole-3-acetic acid produced by the fungus, Pythium aphanidermatum.

Pythium aphanidermatum causes the serious disease of Pythium red blight on bentgrass. IAA, one of the metabolites that has been isolated from this fungus, showed the same symptom of Pythium red blight on bentgrass at a concentration of 1,000 mg/1. The IAA content in the foliage of bentgrass infected by this fungus was about 200 times that of an untreated control. These results suggest that IAA produced by this fungus was the causal substance of Pythium red blight on bentgrass.

Indoleacetic Acids↗
PubMed2000

Dehydroepiandrosterone suppresses elevated hepatic glucose-6-phosphatase mRNA level in C57BL/KsJ-db/db mice: comparison with troglitazone.

Dehydroepiandrosterone (DHEA) is known to improve hyperglycemia of diabetic C57BL/KsJ-db/db mice that are obese and insulin resistant. In a previous study, we reported that DHEA as well as troglitazone suppresses the elevated hepatic gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and fructose-1,6-bisphosphatase (FBPase) activities in C57BL/KsJ-db/db mice. In the present study, we evaluated the changes in mRNA of G6Pase and FBPase in db/db mice. Despite hyperinsulinemia, the G6Pase mRNA level of db/db mice was elevated as compared to their heterozygote littermate db/+m mice. In contrast, the FBPase mRNA level was not elevated in db/db mice. Administration of DHEA for two weeks significantly decreased the blood glucose level and the elevated G6Pase mRNA level in db/db mice. No significant changes were seen in the FBPase mRNA level after the administration of DHEA. Administration of troglitazone also decreased the blood glucose and G6Pase mRNA level in db/db mice although no changes were seen in the FBPase mRNA level. These results suggest that the elevation of G6Pase mRNA is important in elucidating the cause of insulin resistance, and that the G6Pase gene is at least one target for the hypoglycemic effects of DHEA as an insulin sensitizing agent in db/db mice.

Animals↗
PubMed2000

[Hypersensitivity peumonitis in a patient with rheumatoid arthritis].

We report a case with rheumatoid arthritis and hypersensitivity pneumonitis. A 66-year-old female was admitted to our hospital because of fever, cough, and progressive dyspnea on October 10, 1997. She had a history of rheumatoid arthritis from 1987 and was treated with cyclophosphamide when she developed pulmonary symptoms in September 1997. On admission arthritis was subsided. Fine crackles on ausculation of lung, hypoxia, ground-glass appearance on chest X-ray were detected. The computed tomography of the chest disclosed diffuse interstitial shadow with patchy destruction of alveolar structures. Bronchoalveolar lavage demonstrated an increase in lymphocytes with predominance of suppressor-cytotoxic T cell subset (CD 8+). The histopathological examination of transbronchial lung biopsy showed interstitial inflammation with marked predominance of lymphocyte with intraalveolar exudate. Her condition got better and she discharged without definitive diagnosis and treatment for her respiratory symptoms. Eight hours after she went back home, she suddenly presented high fever and cough and gradually developed dyspnea. She was readmitted 5 days after the previous discharge. Although no specific precipitin antibody against various microorganisms was detected in her sera, the diagnosis of hypersensitivity pneumonitis was made. Thirty mg per day of prednisolone was resolved her symptoms promptly. There was no reported case with hypersensitivity pneumonitis and rheumatoid arthritis of other collagen diseases. The clinical course that arthritis and pulmonary symptoms appeared alternatively is of considerable interest to investigate for the pathogenesis of these two immune disorders.

Aged↗
PubMed1999

CD28-independent costimulation of T cells by OX40 ligand and CD70 on activated B cells.

OX40 and its ligand (OX40L) have been implicated in T cell-dependent humoral immune responses. To further characterize the role of OX40/OX40L in T-B cell interaction, we newly generated an anti-mouse OX40L mAb (RM134L) that can inhibit the costimulatory activity of OX40L transfectants for anti-CD3-stimulated T cell proliferation. Flow cytometric analyses using RM134L and an anti-mouse OX40 mAb indicated that OX40 was inducible on splenic T cells by stimulation with immobilized anti-CD3 mAb in a CD28-independent manner, while OX40L was not expressed on resting or activated T cells. OX40L was inducible on splenic B cells by stimulation with anti-IgM Ab plus anti-CD40 mAb, but not by either alone. These activated B cells exhibited a potent costimulatory activity for anti-CD3-stimulated T cell proliferation and IL-2 production. Anti-CD80 and anti-CD86 mAbs partially inhibited the costimulatory activity, and further inhibition was obtained by their combination with RM134L and/or anti-CD70 mAb. We also found the anti-IgM Ab- plus anti-CD40 mAb-stimulated B cells exhibited a potent costimulatory activity for proliferation of and IL-2 production by anti-CD3-stimulated CD28- T cells from CD28-deficient mice, which was substantially inhibited by RM134L and/or anti-CD70 mAb. These results indicated that OX40L and CD70 expressed on surface Ig- and CD40-stimulated B cells can provide CD28-independent costimulatory signals to T cells.

Animals↗
PubMed1999

Nanometer Deformation Caused by the Laplace Pressure and the Possibility of Its Effect on Surface Tension Measurements.

The deformation of solid surfaces caused by the Laplace pressure is analyzed ad its effect on the meniscus force measurement is discussed by comparing it with the published experimental results of the meniscus force on a surface force apparatus. It is found theoretically that the deformation reaches the order of several nanometers and reduces greatly the meniscus force when the meniscus curvature radius is small. It is concluded that the deviation of the measured meniscus force with the surface force apparatus from equation F = 4pigammaR cos &theta; for a nanometer meniscus is due neither to the hydrogen bonding interaction (Fisher and Israelachvili, Colloids and Surf. 3, 303 (1981)) nor to the short range solid-solid interaction (Christenson, J. Colloid Interface Sci. 121, 170 (1988)). The main reason lies in the deformation of the solid surface due to the Laplace pressure. The nanometer deformation of solid surfaces caused by the Laplace pressure is of great importance in measuring the meniscus force. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Coloanal anastomosis using a circular stapling device following perineal rectosigmoidectomy for rectal prolapse.

Perineal rectosigmoidectomy with a hand-sewn anastomosis is thought to be the most appropriate procedure for elderly patients deemed unfit to tolerate a major abdominal operation. However, the use of a circular stapling device to perform the coloanal anastomosis following rectosigmoidectomy shortens the operative time and provides a more secure anastomosis than the traditional hand-sewn technique.

Anal Canal↗
PubMed1999

High ligation of the inferior mesenteric artery with hypogastric nerve preservation in rectal cancer surgery.

We describe herein a technique of performing upward node dissection following high ligation of the inferior mesenteric artery for patients with T3 and T4 rectal carcinomas. The course of the hypogastric nerve is confirmed macroscopically during the procedure to ensure its preservation. This technique offers both increased radicality and the prevention of ejaculatory dysfunction.

Digestive System Surgical Procedures↗
PubMed1999

Influence of genotypes at SAA1 and SAA2 loci on the development and the length of latent period of secondary AA-amyloidosis in patients with rheumatoid arthritis.

To examine whether polymorphism at the SAA loci is associated with the development of amyloid protein A (AA)-amyloidosis, we determined the genotypes at the SAA1 and SAA2 loci in 43 AA-amyloidosis patients (amyloidosis population) and 77 patients with rheumatoid arthritis (RA) who had been ill for less than 5 years (early RA population). We also compared the frequencies of the genotypes at the SAA1 locus among 90 Korean, 95 Taiwanese, and 103 Japanese healthy subjects. The frequencies of the gamma/gamma genotype and gamma alleles at the SAA1 locus were significantly higher in the amyloidosis population than in the early RA population (34.9% versus 7.8%, and 58.1% versus 33.8%, chi2 test P=0.0001). The frequencies of the gamma allele at the SAA1 locus in Koreans, Taiwanese, and Japanese were 41.6%, 35.6%, and 37.4%, respectively. The length of the latent period of AA-amyloidosis was significantly longer in the patients with smaller numbers of the gamma allele at the SAA1 locus (Spearman's correlation coefficient: -0.42, P<0.05). On the other hand, the mean C-reactive protein (CRP) level during 2 years prior to the diagnosis of AA-amyloidosis was significantly higher in the patients with larger numbers of the gamma allele at the SAA1 locus (Spearman's correlation coefficient: 0.34, P<0.05). No significant association was found between amyloidosis and polymorphism at the SAA2 locus. We postulate that the allele SAA1gamma renders an RA patient susceptible to amyloidosis, possibly by affecting the severity of inflammation in RA.

Adult↗
PubMed1999

EPR imaging for in vivo analysis of the half-life of a nitroxide radical in the hippocampus and cerebral cortex of rats after epileptic seizures.

Recently, we developed an in vivo temporal electron paramagnetic resonance (EPR) imaging technique to be applied to the brain of a rat, into which a blood-brain barrier (BBB)-permeable nitroxide radical, 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM) was injected intraperitoneally. This imaging technique made it possible to measure decay rates of a nitroxide radical in multiple regions of the brain simultaneously. Using this technique, the half-life of PCAM was estimated from the exponential decay of the signal intensity derived from the temporal EPR images in the hippocampus and cerebral cortex of rats after a kainic acid (KA)-induced seizure. The hippocampal half-life of PCAM after KA-induced seizures was significantly prolonged (p < .01), whereas the prolongation of the cortical half-life was not significant. These findings suggest that following a KA-seizure, the intrahippocampal ability to reduce the nitroxide radical is impaired, but the ability is intact in the cerebral cortex. This is the first in vivo quantitative EPR imaging study that has a bearing on the pathogenesis of KA-induced seizures in the brain.

Animals↗
PubMed1999

Selective accumulation of CCR5+ T lymphocytes into inflamed joints of rheumatoid arthritis.

Chemokines and their receptors play critical roles in the selective recruitment of various subsets of leukocytes. Recent studies have indicated that some chemokine receptors are differentially expressed on Th1 and Th2 cells. However, available data concerning the presence of T cells with a Th1 or a Th2 character and the expression of chemokine receptors on infiltrating T cells in the rheumatic joint are still limited. In this study, we investigated the expression of CC chemokine receptor 4 (CCR4) and CCR5, which have been shown to be preferentially expressed on Th2 and Th1 respectively on T cells from rheumatoid arthritis (RA) patients. Although both CCR5+ and CCR4+ CD4+ T cell populations were observed in peripheral blood mononuclear cells from healthy controls and osteoarthritis patients, these cell populations were decreased in patients with active RA. In contrast, the vast majority of synovial fluid (SF) T cells from active RA patients expressed CCR5 but not CCR4. CCR5 ligands, MIP-1alpha and RANTES, were found in RA SF at high levels. CCR5+ CD4+ T cells from SF mononuclear cells of RA patients produced IFN-gamma but not IL-4 in response to anti-CD3 stimulation in vitro. These results indicated that differential expression of chemokine receptors plays a critical role for selective recruitment of pro-inflammatory T cells into the joints of RA.

Adult↗