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N Mori

Publications and source records attributed to N Mori.

At least 181 records · Page 10Linked to original sources
PubMed1999

Extracellular ATP-induced inward current in isolated epithelial cells of the endolymphatic sac.

Using whole-cell patch-clamp technique and Fura-2 fluorescence measurement, the presence of ATP-activated ion channels and its dependence on intracellular Ca2+ concentration ([Ca2+]i) in the epithelial cells of the endolymphatic sac were investigated. In zero current-clamp configuration, the average resting membrane potential was -66.8+/-1.3 mV (n=18). Application of 30 microM ATP to the bath induced a rapid membrane depolarization by 43.1+/-2.4 mV (n=18). In voltage-clamp configuration, ATP-induced inward current at holding potential (VH) of -60 mV was 169.7+/-6.3 pA (n=18). The amplitude of ATP-induced currents increased in sigmoidal fashion over the concentration range between 0.3 and 300 microM with a Hill coefficient (n) of 1.2 and a dissociation constant (Kd) of 11.7 microM. The potency order of purinergic analogues in ATP-induced current, which was 2MeSATP>ATPgammas>/=ATP>alpha, beta-ATP>ADP=AMP>/=adenosine=UTP, was consistent with the properties of the P2Y receptor. The independence of the reversal potential of the ATP-induced current from Cl- concentration suggests that the current is carried by a cation channel. The relative ionic permeability ratio of the channel modulated by ATP for cations was Ca2+>Na+>Li+>Ba2+>Cs+=K+. ATP (10 microM) increased [Ca2+]i in an external Ca2+-free solution to a lesser degree than that in the external solution containing 1.13 mM CaCl2. ATP-induced increase in [Ca2+]i can be mimicked by application of ionomycin in a Ca2+-free solution. These results indicate that ATP increases [Ca2+]i through the P2Y receptor with a subsequent activation of the non-selective cation channel, and that these effects of ATP are dependent on [Ca2+]i and extracellular Ca2+.

Adenosine Triphosphate↗
PubMed1999

A neurally enriched coronin-like protein, ClipinC, is a novel candidate for an actin cytoskeleton-cortical membrane-linking protein.

Brain-enriched human FC96 protein shows a close sequence similarity to the Dictyostelium actin-binding protein coronin, which has been implicated in cell motility, cytokinesis, and phagocytosis. A phylogenetic tree analysis revealed that FC96 and two other mammalian molecules (p57 and IR10) form a new protein family, the coronin-like protein (Clipin) family; thus hereafter we refer to FC96 as ClipinC. A WD domain and a succeeding alpha-helical region are conserved among coronin and Clipin family members. ClipinC is predominantly expressed in the brain, and discrete areas in the mouse brain were intensely labeled with anti-ClipinC antibodies. ClipinC was also shown to bind directly to F-actin in vitro. Immunocytochemical analysis revealed that ClipinC accumulated at focal adhesions as well as at neurite tips and stress fibers. Furthermore, ClipinC was associated with vinculin, which is a major component of focal contacts. These results indicate that ClipinC is also a component part of the cross-bridge between the actin cytoskeleton and the plasma membrane. These findings and the previously reported function of coronin suggest that ClipinC may play specific roles in the reorganization of neuronal actin structure, a change that has been implicated in both cell motility and growth cone advance.

Actins↗
PubMed1999

Constitutive activation of NF-kappaB in primary adult T-cell leukemia cells.

Human T-cell leukemia virus type I (HTLV-I) is an etiologic agent of adult T-cell leukemia (ATL). The viral protein Tax induces the activation and nuclear translocalization of transcription factor NF-kappaB, which is proposed to play a crucial role in the transformation of T cells by HTLV-I. However, the HTLV-I genes including Tax are not expressed significantly in primary leukemic cells from ATL patients. In this study, we examined the basis for NF-kappaB activation in freshly isolated leukemic cells from ATL patients. We found that leukemic cells from ATL patients, like HTLV-I-infected T-cell lines, display constitutive NF-kappaB DNA binding activity and increased degradation of IkappaBalpha (an inhibitor of NF-kappaB). Whereas the NF-kappaB binding activity in Tax-expressing T-cell lines consisted mostly of p50/c-Rel, fresh ATL samples contained p50/p50 and p50/p65 heterodimers. One T-cell line derived from ATL leukemic cells, TL-Om1, displayed constitutive NF-kappaB activity, as well as enhanced degradation of IkappaBalpha, despite the lack of detectable Tax expression. Interestingly, the NF-kappaB in TL-Om1 consists of p50/p50 and p50/p65 like that in fresh primary leukemic cells. Our results suggest that activation of NF-kappaB occurs through a Tax-independent mechanism in leukemic cells of ATL patients, possibly due to differential NF-kappaB subunit activation.

DNA, Neoplasm↗
PubMed1999

Hodgkin disease with subsequent transformation to CD30 positive non-hodgkin lymphoma in six patients.

BACKGROUND: Previous studies have indicated that some patients with Hodgkin disease have an aggressive clinical course. However, their characteristics have not been elucidated. METHODS: Six patients initially diagnosed as having Hodgkin disease with subsequent transformation to CD30 positive non-Hodgkin lymphoma were clinically and immunohistochemically studied. Ten patients with classic anaplastic large cell lymphoma (ALCL) and 19 patients with classic Hodgkin disease were studied for comparison by immunohistochemistry. RESULTS: Five patients, excluding one whom the authors recently encountered, had an aggressive clinical course and died within approximately 1 year after diagnosis; four of them were autopsied. Common histologic findings in the six patients included sheets of atypical mononuclear cells and sinusoidal infiltration of small numbers of these cells, as well as Reed-Sternberg cells or lacunar cells. Follow-up biopsies revealed histologic progression to ALCL in which sheets of atypical mononuclear or multinucleated cells spread throughout the lymph nodes. Immunohistochemically, epithelial membrane antigen, granzyme B, perforin, and pancadherin were expressed frequently in the six patients and in ALCL but were not expressed in Hodgkin disease. Latent membrane protein-1 (LMP-1) and Epstein-Barr virus-encoded RNA (EBER-1) were totally negative in the six patients and in ALCL but were expressed frequently in Hodgkin disease. In contrast, LeuM1 (CD15) was expressed frequently in the six patients and in Hodgkin disease, whereas it was not expressed in ALCL. MT1 (CD43), UCHL-1 (CD45RO), and P80 were totally negative in the six patients and in Hodgkin disease, whereas they were expressed variably in ALCL. CONCLUSIONS: These results suggest that the six patients studied had intermediate phenotypes between ALCL and Hodgkin disease. The authors also suggest that patients with sheets of atypical mononuclear cells and sinusoidal infiltration of atypical mononuclear and multinucleated cells have an aggressive clinical course and should be treated with intensive chemotherapy.

Adult↗
PubMed1999

Frequent loss of heterozygosity on chromosomes 4, 12 and 19 in radiation-induced lymphomas in mice.

We found frequent loss of heterozygosity (LOH) on chromosomes 4, 12 and 19 in radiation-induced lymphomas from (BALB/cHeA x STS/A) F1 hybrid mice by allelotype analysis at polymorphic microsatellite loci. The incidences of LOH were 27% (20 of 74 lymphomas), 57% (42 of 74 lymphomas) and 50% (37 of 74 lymphomas) on chromosomes 4 (at D4Mit31), 12 (at D12Mit17) and 19 (at D19Mit11), respectively. These frequent LOH regions are homologous to human chromosomes 9p and 1p, chromosome 12q32.1 and chromosome 10q, respectively. Strain-specific preferential allele loss was observed only on chromosome 4. However, no bias in the frequency of loss between alleles of maternal and paternal origin was observed, indicating that genomic imprinting may not be predominantly involved in these lymphomas. The results suggest that these three regions might harbor tumor suppressor genes responsible for this lymphomagenesis.

Animals↗
PubMed1999

Dynamics of prostate cancer cell invasion studied in vitro by NMR microscopy.

Understanding the dynamics and pathogenesis of invasion is vital for developing strategies to prevent cancer metastasis. Conventional invasion assays provide information for a single time point. NMR microscopic imaging as used in the current study to measure cell invasion in vitro provides a nondestructive method for scoring cell invasion thus offering a unique possibility to study this process dynamically. An additional advantage is that cells can be retrieved for metabolic and physiological characterization. Two prostate cancer cell lines, DU-145 and Mat-Ly-Lu, preselected for differences in invasive behavior, were studied. Cells were seeded in 12-mm culture plate inserts containing a 15-microm-thick porous membrane with 3.0 microm pore size that was coated with a 100 microm Matrigel layer. Cell invasion in the Matrigel layer was obtained from the profile of intracellular water measured with diffusion-weighted 1D imaging. Additional experiments were also performed with confocal microscopy to validate the NMR results. Significant differences were detected between the invasive behavior of DU-145 and Mat-Ly-Lu cells. The obtained results show that NMR microscopy can be used to dynamically study invasion by cancer cells. The noninvasive nature of NMR microscopy permits determination of cell migration dynamically for any given sample, which is especially important if cell availability is limited to the unique sample, such as for biopsy specimens. Magn Reson Med 42:277-282, 1999.

Animals↗
PubMed1999

Genetic transformation of a Rhizomucor pusillus mutant defective in asparagine-linked glycosylation: production of a milk-clotting enzyme in a less-glycosylated form.

Rhizomucor pusillus 1116R3 has a defect in alg2 encoding a mannosyltransferase in the asparagine (N)-linked oligosaccharide biosynthetic pathway and produces proteins in less-glycosylated forms. For development of a genetic transformation system for this zygomycete, an uracil auxotroph (mutant 1116U17) as the host strain was derived by ultraviolet (UV) mutagenesis as 5-fluoroorotic acid-resistant colonies and the orotidine-5'-monophosphate (OMP) decarboxylase (pyr4) gene as a selection marker was cloned from the wild-type strain R. pusillus F27 by the polymerase chain reaction with primers designed on the basis of the pyr4 sequences from other fungi. The amino acid sequence of R. pusillus Pyr4 deduced from the nucleotide sequence showed high homology with the OMP decarboxylases from various fungi. The pyr4 gene on pUC19 (plasmid pRPPyr4) was introduced into protoplasts of R. pusillus 1116U17 by polyethylene glycol-assisted transformation. Transformation under optimized conditions yielded 5 Ura+ transformants with 1 microgram pRPPyr4 DNA and 1 x 10(7) viable protoplasts. Southern blot analysis of the genomic DNA from the transformants showed that multiple copies of the pRPPyr4 sequence were integrated into the genome by homologous recombination at the pyr4 locus. For the purpose of production of a milk-clotting aspartic proteinase (MPP) in a less-glycosylated form, mpp from the wild-type strain was cloned in pRPPyr4 and introduced into protoplasts of R. pusillus 1116U17. Transformants obtained in this way contained multiple copies of mpp at the chromosomal mpp locus and produced MPP as a mixture of molecules having no sugar chains and Man0-1GlcNAc2 at the two N-linked glycosylation sites in an amount about 12 times larger than the parent strain. The transformation system for R. pusillus 1116U17 would be useful for production of proteins with truncated N-linked oligosaccharide chains.

Amino Acid Sequence↗
PubMed1999

Laparoscopic resection of large leiomyomas of the gastric fundus.

Two patients with a large leiomyoma arising from the gastric fundus underwent laparoscopic resection. In case 1, the tumor was located in the anterior wall of the gastric fundus. To prevent stenosis and preserve the volume of the residual stomach, intragastric resection was adopted. The tumor was markedly and resected with laparosonic coagulating shears with a 1-cm safety margin. In case 2, a large tumor was detected in the duodenal bulb. Serious hemorrhage mandated emergency resection. The tumor originated from the posterior wall of the fundus. Attempts at reduction with the forceps failed. Reduction by digital manipulation via laparoscopic port sites was successful. An endostapler was used to resect the tumor and close the anterior wall. Both patients recovered uneventfully.

Aged↗
PubMed1999

Determination of age-related changes in human soluble interleukin 2 receptor in body fluids of normal subjects as a control value against disease states.

A highly sensitive enzyme-linked immunosorbent assay (ELISA) system was developed for human soluble interleukin-2 receptor (sIL-2R) with an ELISA-amplification system (ELAST((R))). The sensitivity of the new method was 20-fold higher than that without the amplification. Thus very low concentrations of sIL-2R in urine can be detected. With this method, serum and urine concentrations of sIL-2R were analyzed for healthy Japanese subjects with age 1-67 years. Mean sIL-2R concentrations in both serum and urine of children were significantly higher than those of adults. However, the concentrations of children showed a progressive decline to those of adults by the age of 15 years. There was no difference in the values between males and females. The results provide a control value of sIL-2R against those in disease states such as nephrotic syndrome. Since the trends in serum and urine were found to be similar, urinary sIL-2R measurement may provide sufficient information, without measuring the blood concentration.

Adolescent↗
PubMed1999

Angiotensin II receptor blockade limits kidney injury in two-kidney, one-clip Goldblatt hypertensive rats with special reference to phenotypic changes.

Recent evidence indicates that tubulointerstitial injury plays an important role in hypertensive kidney injury and that phenotypic changes contribute to this pathology. Moreover, angiotensin II is known to be actively involved in the pathogenesis of progressive kidney injury induced by hypertension. The present study was undertaken to see the effect of a newly developed angiotensin II type I receptor (AT1 receptor) antagonist on hypertension-induced kidney injury and to determine the contribution of phenotypic changes to morphologic alterations. Two-kidney, one-clip (2K1C), Goldblatt hypertensive rats (n = 27) were made by clipping the left renal artery. These animals were orally administered 57G709 (a selective non-peptide AT1 receptor antagonist)(10 mg/kg/day), captopril (20 mg/kg/day), or vehicle alone for 23 days beginning 4 weeks after clipping. In the non-clipped kidney of vehicle-treated 2K1 C rats, marked tubulointerstitial injury as well as glomerular sclerosis and/or hyalinosis was found in association with phenotypic changes, as shown by the neoexpression of vimentin in periglomeruli, perivascular walls, distal tubuli, and injured interstitium. Renin expression was markedly suppressed in the non-clipped kidneys of vehicle-treated 2K1C rats as compared with renin expression in normotensive control kidneys of sham-operated rats. Both 57G709 and captopril markedly ameliorated hypertensive kidney injury as reflected by the glomerular sclerosing index and by the tubulointerstitial index as determined by the point-counting method, and this improvement was accompanied by a significant decrease in blood pressure, urinary protein excretion, kidney/body weight ratio, and heart/body weight ratio. In addition, the vimentin neoexpression mentioned above was also suppressed with an inhibition of angiotensin II. These results suggest that in 2K1C Goldblatt hypertensive kidney injury, the AT1 receptor antagonist 57G709 exerts a potent renal protective effect associated with the inhibition of phenotypic changes.

Angiotensin Receptor Antagonists↗
PubMed1999

Pelvic malignant mixed mesodermal tumor of uncertain origin: a case report.

Extra-uterine, and especially extragenital, malignant mixed mesodermal tumors (MMMT) are very rare. A large intrapelvic tumor resected from a 56-year-old woman was investigated with morphological and immunohistochemical methods. A large, soft and fragile tumor was located in the pelvic space. The tumor showed high cellularity and was biphasic; it consisted of an admixture of adenocarcinoma and various kinds of sarcomas. The latter were comprised of high-grade endometrial stromal sarcoma, pleomorphic sarcoma, and chondrosarcoma. The pleomorphic sarcoma showed a storiform pattern. The periodic acid-Schiff-positive eosinophilic hyaline droplets and globules in multinucleated giant cells revealed a typical ring-like or peripheral staining for alpha-1-antitrypsin and alpha-1 antichymotrypsin. We considered this case to be pelvic MMMT of uncertain origin, heterologous type.

Combined Modality Therapy↗
PubMed1999

Differential regulation of the growth-associated proteins, GAP-43 and SCG-10, in response to unilateral cortical ablation in adult rats.

Synapse replacement after brain injury has been widely documented by anatomical studies in various parts of both the developing and adult nervous system. However, the molecular events that define the specificity of the empirically derived rules of reactive synaptogenesis in different regions of the adult brain remain unclear. In this study we examined the differential regulation of the lesion-induced response of the two growth-associated proteins, superior cervical ganglia-10 and growth-associated protein-43, after unilateral cortex ablation, and determined a hierarchical order for the lesion response from remaining afferent projection neurons originating from the contralateral cortex, ipsilateral thalamus and substantia nigra. We report that in response to unilateral cortex ablation both messenger RNA, by northern blot, and protein, by western blot, for superior cervical ganglia-10 but not growth-associated protein-43 was increased in the homologous area of the contralateral cortex but not the ipsilateral thalamus or substantia nigra. In addition, the specificity of the superior cervical ganglia-10 response, assessed by combined in situ hybridization and retrograde FluoroGold labeling of striatal afferent neurons, found that superior cervical ganglia-10 messenger RNA was increased prominently in layer V pyramidal neurons of the contralateral corticostriatal pathway but was unchanged in afferent projection neurons from the thalamus and substantia nigra. Furthermore, the increase in both superior cervical ganglia-10 messenger RNA and protein seen at three days postlesion in contralateral corticostriatal neurons coincides in time with the initiation of neurite outgrowth in the deafferented striatum by contralateral corticostriatal axons described in our previous ultrastructural study. However, if cortical input to the striatum was removed bilaterally the lesion-induced response for superior cervical ganglia-10 messenger RNA shifted secondarily to thalamostriatal neurons in the ipsilateral thalamus. These data provide evidence that superior cervical ganglia-10 and growth-associated protein-43 are differentially regulated in neurons of the contralateral corticostriatal pathway in response to unilateral cortex ablation and suggests that superior cervical ganglia-10 plays a role in the regulation of neurite outgrowth in the adult striatum after brain injury. However, the specific role that superior cervical ganglia-10 may play in reactive synaptogenesis remains unclear. In addition, our data suggest that a hierarchical order exists for the reinnervation of deafferented striatal neurons after unilateral cortex ablation with preference given to homologous axons from the contralateral cortex.

Animals↗
PubMed1999

A case of natural killer/T cell lymphoma of the subcutis resembling subcutaneous panniculitis-like T cell lymphoma.

A case of nasal type natural killer (NK)/T cell lymphoma of the subcutis showing clinical and morphological features that resemble subcutaneous panniculitis-like T cell lymphoma (SPTCL) is presented. A 73-year-old man presented with swelling of the left arm and was diagnosed with panniculitis by a dermatologist. It was concluded from a skin biopsy specimen that the patient had non-Hodgkin's lymphoma of the large cell, NK/T cell type because the neoplastic cells showed polyclonal CD3 immunoreactivity. Treatment with interferon-gamma was initiated, but the patient died of disseminated intravascular coagulation and multiple organ failure 2 months after the initial symptoms appeared. However, involvement of additional organs by the lymphoma was not apparent clinically. An autopsy was not performed. A routinely stained section of the biopsy skin specimen revealed massive necrosis of the subcutaneous fat, karyorrhexis admixed with reactive histiocytes, and large atypical lymphoid cells. Immunoreactivity for polyclonal CD3 was present in the perinuclear region, but absent in the neoplastic cell membranes. CD56, CD45RO (UCHL-1), CD43 (MT1), CD45 (leukocyte common antigen), and the cytotoxic molecules perforin, granzyme B and TIA-1 were positive, but CD20 (L26), CD4, CD8, and betaF1 were negative. Epstein-Barr virus (EBV) mRNA was detected in the nuclei of neoplastic cells by in situ hybridization. Subcutaneous panniculitis-like T cell lymphoma is reported to be an EBV-negative, clonal T cell neoplasm. Although this case showed clinical and morphological features that resembled SPTCL, perinuclear polyclonal CD3 staining and membranous CD56 reactivity seen in neoplastic cells were suggestive of NK cells. Furthermore, the neoplastic cells were positive for EBV. This case is considered to be a NK/T cell lymphoma of the subcutis resembling SPTCL. It is believed that it is important to recognize such a tumor because patients may undergo a fulminant clinical course, despite the tumor being localized in the subcutaneous adipose tissue.

Aged↗
PubMed1999

An autopsy case of primary nodal plasmacytoma associated with Sjögren's syndrome.

An 81-year-old man with a 1 year history of Sjögren's syndrome and hypergammaglobulinemic purpura was admitted because of high fever and lymphadenopathy. Primary nodal plasmacytoma was suggested from the microscopic and immunohistochemical findings of an inguinal lymph node biopsy specimen. Although chemotherapy achieved a moderate response, the patient died 2 months later from respiratory and cardiac failure. We herein, is described a rare autopsy case of primary nodal plasmacytoma associated with Sjögren's syndrome, in which the clinical course was progressive and Epstein-Barr virus-encoded RNA 1 was positive in a small number of neoplastic plasma cells, showing some difference from previously reported cases.

Aged↗
PubMed1999

Expression of mRNAs encoding hormone receptors in the endolymphatic sac of the rat.

The endolymphatic sac (ES) is believed to absorb the endolymphatic fluid produced by the stria vascularis and vestibular dark cells. Recent studies have implied that the function of the ES may be controlled by circulating hormones, suggesting that hormone receptors should exist there. In the present study, the expression of genes encoding receptors for aldosterone, atrial natriuretic peptide (ANP) and vasopressin in the ES was examined by reverse transcription-polymerase chain reaction (RT-PCR). Next, the cellular localization of the expression of these genes was investigated by in situ hybridization. RT-PCR indicated that aldosterone. ANP-A and vasopressin V1a receptor genes were expressed in the ES. In contrast, neither ANP-B nor vasopressin V2 receptor gene expression was detected. In situ hybridization experiments demonstrated aldosterone receptor gene expression in epithelial cells of the intermediate potion of the ES, while expression of ANP-A or V1a receptor genes was not detected. The present results suggested that aldosterone may play a specific role in the function of the ES. However, we could not conclude that ANP and vasopressin play physiological roles in the ES because receptors for these hormones were detected only by highly sensitive PCR.

Aldosterone↗
PubMed1999

Non-Hodgkin's lymphoma followed by plasmacytoma, both arising in A thyroid gland with Hashimoto's disease.

We describe here a rare case of malignant lymphoma followed by plasmacytoma in Hashimoto's thyroiditis. The patient developed malignant lymphoma (small, non-cleaved cell, and non Burkitt's type by Working Formulation classification), and remained in remission for 2 years after receiving combination chemotherapy, and then developed plasmacytoma in the same lesion. Rearrangement bands for IgH from both specimens showed different bands, indicating that both were of monoclonal type but of a different clonal origin. Considering the clinical course in this case, thyroidectomy may be indicated for lymphoproliferative diseases in Hashimoto's thyroiditis treated with chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗