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S Mitani

Publications and source records attributed to S Mitani.

At least 55 records · Page 3Linked to original sources
PubMed1993

Calretinin-immunoreactivity in trigeminal neurons innervating the nasal mucosa of the rat.

Trigeminal primary neuronal cell bodies were labeled by retrograde transport of Fluoro-gold (FG) from the nasal mucosa of rats. The trigeminal ganglion containing the labeled cell bodies were processed for double stain for calretinin- and tachykinin-immunoreactivities (CR- and TK-irs). Except for a few contralateral cells, all the cells that innervated the nasal mucosa (NM cells) were confined to the ophthalmo-maxillary division of the trigeminal ganglion ipsilateral to the FG application. In the dorsal two-thirds of the ganglion, NM cells formed a cluster in the rostromedial part of ophthalmo-maxillary division (the rostromedial cluster). In the ventral third, the number of cells in the rostromedial cluster markedly decreased. Instead, numerous NM cells were found in the caudolateral part of the ophthalmo-maxillary division (the caudoventrolateral cluster). CR- and TK-irs were detected in 18% and 54% of overall population of NM cells, respectively. Virtually all of CR-immunoreactive (-ir) NM cells coexpressed TK. Although the proportion of TK-ir cells, irrespective of CR-ir, was similar for both clusters, CR-ir cells were more frequent in the caudoventrolateral cluster than in the rostromedial cluster. In the dorsal 1/3 of the ganglion where all the NM cells belonged to the rostromedial cluster, only 8.4% exhibited CR-ir. On the other hand, as much as 30.1% of NM cells expressed CR-ir in the ventral 1/3 where most NM cells were found in the caudoventrolateral cluster. Trigeminal cell bodies innervating the cornea and conjunctivum were located in the rostromedial part of the ophthalmo-maxillary division.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

c-Fos expression by dorsal horn neurons chronically deafferented by peripheral nerve section in response to spared, somatotopically inappropriate nociceptive primary input.

Subcutaneous formalin injection into the hindpaw of rats induces c-Fos expression in neurons in the ipsilateral spinal cord dorsal horn. In laminae I and II of the dorsal horn at the junction of 4th and 5th segments of the lumbar spinal cord, neurons exhibiting c-Fos protein-like immunoreactivity (Fos-LI) are concentrated in the medial 3/4 that correspond to the terminal field of primary neurons innervating the sciatic nerve. Subacute tibial nerve section 24 h before formalin stimulation caused almost complete elimination of neurons with the formalin-induced Fos-LI in the medial 1/2 (tibial territory) of the above sciatic territory of the dorsal horn. Following a longer survival period (chronic tibial nerve section of 21 days standing), neurons with the formalin-induced Fos-LI re-appeared in the tibial territory. In addition, the number of neurons with the formalin-induced Fos-LI increased in the medial part of the peroneal territory (the lateral 1/2 of the sciatic territory). The results indicate that the activation of c-Fos expression in that part of dorsal horn that has been chronically deafferented by the tibial nerve section is taken over by the spared, but somatotopically inappropriate primary nociceptors. Furthermore, dorsal horn neurons outside but near the deafferented tibial nerve's territory exhibit hypersensitivity to c-Fos expression evoked by intact, somatotopically appropriate primary nociceptive input.

Animals↗
PubMed1993

Propentofylline (HWA285) inhibits the release of dopamine during transient ischemia and modulates its metabolism in rat striatum.

Propentofylline (HWA285) has been reported to protect neuronal cells through the inhibition of glutamate release during transient ischemia. We studied whether HWA285 inhibits dopamine (DA) release, and how HWA285 modulates DA metabolism in the rat model. HWA285 was perfused through a microdialysis probe placed in the rat striatum during 20 min transient ischemia. In rats perfused by HWA285, ischemic DA release was significantly inhibited, and DA metabolism showed better recovery in contrast with unperfused rats.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1993

bcl-2 gene rearrangement analysis of Japanese follicular lymphomas by polymerase chain reaction in formalin-fixed, paraffin-embedded tissue specimens.

The prevalence of chromosomal translocation t(14;18) was examined in 41 cases of follicular lymphoma covering all histopathological subtypes, using the polymerase chain reaction and hybridization method with non-radioactive oligonucleotide probes. DNAs were extracted from unfixed fresh-frozen and/or formalin-fixed paraffin-embedded biopsy specimens. The t(14;18) chromosomal translocation, resulting in bcl-2-JH (immunoglobulin heavy chain gene joining segment) fusion gene, was detected in 7 (36.8%) of 19 follicular small cleaved cell lymphomas and 6 (54.5%) of 11 follicular mixed, small cleaved cell and large cell lymphomas. Meanwhile, 11 cases of follicular large cell lymphoma revealed no bcl-2-JH fusion gene. There was a statistically significant difference in the frequency of bcl-2-JH rearrangement between follicular, small cleaved cell and large cell lymphoma (two-sided Fisher exact test, P = 0.049). The difference of bcl-2 rearrangement frequency between follicular, mixed and large cell lymphoma was also statistically significant (P = 0.012).

Base Sequence↗
PubMed1993

Combinatorial control of touch receptor neuron expression in Caenorhabditis elegans.

Six touch receptor neurons with distinctive morphological features sense gentle touch in Caenorhabditis elegans. Previous studies have identified three genes (lin-32, unc-86 and mec-3) that regulate touch cell development. However, since other cell types also require these genes, we suspected that other genes help restrict the expression of touch cell characteristics to the six neurons seen in the wild type. To identify such genes, we have examined mutants defective in genes required for the development of other C. elegans cells for changes in the pattern of touch cell-specific features. Mutations in seven genes either reduce (lin-14) or increase (lin-4, egl-44, egl-46, sem-4, ced-3 and ced-4) the number of touch receptor-like cells. The combinatorial action of these genes, all of which are required for the production of many cell types, restrict the number of cells expressing touch receptor characteristics in wild-type animals by acting as positive and negative regulators and by removing cells by programmed cell death.

Animals↗
PubMed1992

Relationship of Helicobacter pylori to serum pepsinogens in an asymptomatic Japanese population.

A seroepidemiologic study of the prevalence of Helicobacter pylori infection in Japan was performed, and the relationship between serum pepsinogen I and II levels (markers of gastritis and gastric atrophy) and H. pylori infection was investigated. Four hundred and eighteen asymptomatic children and adults were studied. The prevalence of anti-H. pylori immunoglobulin G antibody increased with age. For persons born after 1950, the frequency of H. pylori infection increased at approximately 1% per year; for those born before 1950 the prevalence was high (70%-80%) and relatively constant. Serum pepsinogen I and II levels were significantly higher in H. pylori-infected volunteers than in H. pylori-uninfected volunteers [51.6 +/- 3 vs. 42.9 +/- 2 ng/mL (P less than 0.05) for pepsinogen I; 16.0 +/- 1 vs. 7.5 +/- 0.8 ng/mL (P less than 0.001) for pepsinogen II]. The ratio of pepsinogen I to pepsinogen II was significantly lower in H. pylori-infected volunteers (3.5 +/- 0.2) than in uninfected volunteers (6.3 +/- 0.3; P less than 0.001). The apparent decrease in prevalence of H. pylori accompanying the Westernization of Japan may eventually be accompanied by a reduction in the frequency of atrophic gastritis, the precursor lesion of the epidemic form of gastric carcinoma, and ultimately result in a decrease in the incidence of gastric carcinoma in Japan.

Adolescent↗
PubMed1992

Usefulness of hemilaminectomy for microsurgical management of intraspinal lesions.

Hemilaminectomy is a limited, unilateral approach to the spinal cord that provides excellent exposure of the dorsolateral and ventral portions of the spinal canal. This approach is most suitable for microsurgical management of the majority of extramedullary tumors. Contrary to conventional laminectomy, the posterior supporting structures of the spine are completely preserved on the contralateral side with this access route. The procedure has been applied in 3 patients who harbored a cervical neurilemmoma, a cervical lipoma, and a thoracic neurilemmoma, respectively. Optimal exposure of the lesion was achieved in each case, and each patient's symptoms improved or completely resolved postoperatively. There were no surgical complications. It is concluded that hemilaminectomy combined with microsurgical techniques should be given priority over standard laminectomy in the surgical management of extramedullary lesions arising in the spinal canal.

Female↗
PubMed1991

Inductive differentiation of two neural lineages reconstituted in a microculture system from Xenopus early gastrula cells.

Neural induction of ectoderm cells has been reconstituted and examined in a microculture system derived from dissociated early gastrula cells of Xenopus laevis. We have used monoclonal antibodies as specific markers to monitor cellular differentiation from three distinct ectoderm lineages in culture (N1 for CNS neurons from neural tube, Me1 for melanophores from neural crest and E3 for skin epidermal cells from epidermal lineages). CNS neurons and melanophores differentiate when deep layer cells of the ventral ectoderm (VE, prospective epidermis region; 150 cells/culture) and an appropriate region of the marginal zone (MZ, prospective mesoderm region; 5-150 cells/culture) are co-cultured, but not in cultures of either cell type on their own; VE cells cultured alone yield epidermal cells as we have previously reported. The extent of inductive neural differentiation in the co-culture system strongly depends on the origin and number of MZ cells initially added to culture wells. The potency to induce CNS neurons is highest for dorsal MZ cells and sharply decreases as more ventrally located cells are used. The same dorsoventral distribution of potency is seen in the ability of MZ cells to inhibit epidermal differentiation. In contrast, the ability of MZ cells to induce melanophores shows the reverse polarity, ventral to dorsal. These data indicate that separate developmental mechanisms are used for the induction of neural tube and neural crest lineages. Co-differentiation of CNS neurons or melanophores with epidermal cells can be obtained in a single well of co-cultures of VE cells (150) and a wide range of numbers of MZ cells (5 to 100). Further, reproducible differentiation of both neural lineages requires intimate association between cells from the two gastrula regions; virtually no differentiation is obtained when cells from the VE and MZ are separated in a culture well. These results indicate that the inducing signals from MZ cells for both neural tube and neural crest lineages affect only nearby ectoderm cells.

Animals↗
PubMed1991

[A case of chest wall rhabdomyosarcoma].

A 56-year-old man was admitted to our hospital with right chest pain. Chest X-ray, CT scan and MRI revealed a chest wall tumor and enlarged mediastinal lymph nodes. Percutaneous lung biopsy was performed, and the pathological diagnosis of pleomorphic rhabdomyosarcoma was obtained. The only significant abnormal laboratory finding was elevation of serum NSE (24.5 ng/ml). Although chemotherapy (VAC-ADM) and radiation therapy were performed, the patient died about 7 months after admission. To our knowledge, only 17 cases of chest wall rhabdomyosarcoma have been reported in Japan.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Expression of three cell proliferation-associated antigens, DNA polymerase alpha, Ki-67 antigen and transferrin receptor in nodal and cutaneous T-cell lymphomas.

We studied the expression of three cell proliferation-associated antigens: DNA polymerase alpha, Ki-67 antigen, and transferrin receptor, in 35 T-cell lymphomas of nodal origin (T-NL) and 40 cutaneous T-cell lymphomas (CTCL). Immunohistochemical staining was carried out on frozen tissue sections of these specimens using three monoclonal antibodies, DAKO-PC, CL22-2-42B (DNA polymerase alpha), and OKT9. The proportion of cells positive for CL22-2-42B, DAKO-PC, or OKT9 among all tumor cells was correlated with four histologic subtypes: malignant lymphoma (ML), diffuse, small; mixed; large; and large cell immunoblastic in both T-NL and CTCL. A strong correlation was noted between positivity for CL22-2-42B and that for DAKO-PC or OKT9. On the other hand, no difference in the expression of these three antigens was noted between T-NL and CTCL in the high, intermediate or low grade-malignancy group. In CTCL as well as in T-NL, cells positive for CL22-2-42B, DAKO-PC or OKT9 were significantly more numerous in the high-grade group than the intermediate-grade group, and in the intermediate-grade group than the low-grade group. Furthermore, a significant correlation between survival period and the number of CL22-2-42B-positive cells was noted when the T cell malignancies, CTCL and T-NL were considered (t value = 2.015, p less than 0.05). Thus, the expression of DNA-polymerase alpha, Ki-67 antigen or OKT9 seems to well reflect the biological behavior and/or clinical prognosis of T-cell lymphoma.

Antibodies, Monoclonal↗
PubMed1991

[Liver disorders in patients with Mycoplasma pneumoniae pneumonia].

Liver disorders were reviewed in 76 patients with mycoplasma pneumoniae pneumonia (MP) admitted to Kamo Hospital from 1979 to 1989. Liver dysfunction was detected in 16 patients (21%). Liver disorder were detected in 10% of MP from 1979 to 1980, but in 20% from 1984 to 1985, and in 36% from 1988 to 1989. By multiple regression analysis CRP was found to be the most significant factor among other factors such as prevalence, age, sex, history of smoking, history of drinking, and days after onset of fever.

Adult↗
PubMed1990

In vivo measurement of intra- and extracellular space of brain tissue by electrical impedance method.

An impedance method was applied to evaluate transcellular fluid shifts in ischaemic brain oedema. The admittances (apparent electrical conductivities) of tissues were measured at varied frequencies based on a simple model of an electrical equivalent circuit for tissues, which consisted of Re (resistivity of extracellular fluid), Ri (resistivity of intracellular fluid) and Cm (capacitance of cell membrane). Calculated were Re, Ri, Rinf (resistivity of total fluid), Re/Ri and alpha (Cole-Cole distribution index) of brain tissue by Cole-Cole an arc of a circle. During ischaemia induced by cat middle cerebral artery occlusion (MCAO), the parameters were examined continuously. After MCAO, cerebral blood flow (CBF) decreased to under 10 ml/100 g/min. Then Re and Re/Ri increased, but Ri decreased. These results indicated that fluid shift from extracellular (EC) to intracellular (IC) space occurred after ischaemic insult. Rinf showed no changes during ischaemia of 30 min, which demonstrated no changes of total fluid volume. Using this impedance technique, fluid accumulation and shift may be examined by changes of Re, Ri, Re/Ri and Rinf in various types of brain oedema in vivo.

Animals↗
PubMed1989

Embryonic development of Xenopus studied in a cell culture system with tissue-specific monoclonal antibodies.

An in vitro microculture system of early gastrula cells of Xenopus laevis has been developed; deep layer cells from the lateral marginal zone (prospective somite region) or ventral ectoderm (prospective epidermis region) were fully dissociated, and the desired number of each (1-100) was distributed into a microculture well and cultured under appropriate conditions. When examined with the tissue-specific Mabs (Mu1 for muscle and E3 for epidermis, respectively), a substantial portion of the deep layer cells from the two regions followed their respective normal embryonic fates. It was found that reproducible cellular differentiation was dependent on the intimate reaggregation of dissociated cells and on the size of the resultant aggregate. About 20 lateral marginal zone cells were found to be sufficient, when put into a culture well, for supporting successful muscle differentiation, whereas about 100 ventral ectoderm cells were necessary for epidermal differentiation.

Animals↗
PubMed1989

Retarded gastrulation and altered subsequent development of neural tissues in heparin-injected Xenopus embryos.

Gastrulation was examined in Xenopus embryos injected with various polysaccharides into the blastocoel cavity. The progression of gastrulation was assessed by observing pigmentation and yolk plug size in vegetative view embryos. In heparin- or dextran-sulphate-injected embryos, gastrulation was significantly retarded. This was further confirmed in tissue sections of embryos. In contrast, no such retardation was found in embryos injected with hyaluronic acid or chondroitin sulphate. A quantitative analysis showed that the extent of retardation in heparin- or dextran-sulphate-injected embryos was dose-dependent and that, after the initial retardation of up to 2-3 h, gastrulation progressed at a similar rate to controls. At the time when untreated sibling embryos hatched, embryos injected with heparin or dextran sulphate showed abnormalities in their external appearance and swimming behavior in a dose-dependent manner. When these embryos were examined histologically or immunohistochemically using tissue-specific monoclonal antibodies, it was found that central nervous system (CNS), especially the brain and eye structures, were most severely damaged. The extent of damage was again dose-dependent. In contrast, neural-crest-derived melanophores were abundant even in aneural larvae. No such change was found in embryos injected with hyaluronic acid or chondroitin sulphate.

Animals↗