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Biomedical subjects

N Yanai

Publications and source records attributed to N Yanai.

At least 73 records · Page 4Linked to original sources
PubMed1995

Differentiation capacity toward mesenchymal cell lineages of bone marrow stromal cells established from temperature-sensitive SV40 T-antigen gene transgenic mouse.

Stromal cell lines were established from bone marrow of temperature-sensitive T-antigen gene transgenic mice. These stromal cell lines consisted of fibroblasts, endothelial cells, and preadipocytes. We found that these stromal cell lines exhibited phenotypic changes depending on the inactivation of T-antigen and growth condition; one preadipocyte line was induced toward adipocytes and osteogenic cells, and several preadipocyte and endothelial cell lines were induced toward muscle cells and adipocytes. Some cell lines showed bipotential characters. These results indicated that stromal cells consisting of bone marrow hematopoietic microenvironment are derived from multipotent mesenchymal stem cells.

Adipocytes↗
PubMed1995

Properties of incompletely immortalized cell lines generated from a line established from temperature-sensitive SV40 T-antigen gene transgenic mice.

Kidney tubule cell line (TKC2) established from temperature-sensitive (ts) SV40 T-antigen gene transgenic mice exhibited cell death by apoptosis at nonpermissive temperature (39 degrees C). To learn how immortalization occurs, we generated T-antigen-independent immortalized cells (resistant clones) by culturing TKC2 cells at 39 degrees C. These independently isolated resistant clones exhibited ts properties in T-antigen and contained only wild-type p53. They grew similarly at 39 degrees and at 33 degrees C, but cell death was induced soon after they reached confluency at 39 degrees C. However, cell death was equally prevented by transfecting the bcl-2 gene. While TGF-beta showed no growth-suppressive effect in the sensitive and resistant clones at 33 degrees C, it induced significantly earlier cell death in the resistant clones at 39 degrees C. Thus, the resistant clones may be incompletely immortalized cell lines which induce cell death in response to the growth-suppressive effects of contact inhibition.

Animals↗
PubMed1995

Augmentation of cancer chemotherapy by preinjection of human macrophage colony-stimulating factor in L1210 leukemic cell-inoculated mice.

Human macrophage colony-stimulating factor (hM-CSF) is a potent stimulator of the effector functions of monocytes/macrophages. We investigated the antitumor effects of this factor in CDF1 male mice inoculated with L1210 cells, a mouse B-cell leukemia line. Mice preinoculated with various numbers of L1210 cells on day 0 were given intravenous injections of vehicle (human serum albumin; HSA) (100 micrograms/kg/day) or hM-CSF (20 micrograms/kg/day) for 3 days from day 1. In mice preinoculated with 10(2) L1210 cells but not with 10(3) or more L1210 cells, a marked increment in survival rate was observed with hM-CSF treatment. We next examined the effect of hM-CSF treatment combined with chemotherapy on the survival of mice that had been preinoculated with 10(5) L1210 cells. In our system, the administration of 4.9 mg/kg adriamycin (ADM) alone slightly prolonged survival of the tumor-bearing mice, but all of the mice died within 20 days. When hM-CSF was injected for 3 days before this ADM treatment, the invasion and proliferation of tumor cells in the liver and spleen were markedly inhibited and 50% of the mice were still alive at day 50. We detected inhibitory activity toward L1210 growth in serum of mice administered with hM-CSF, and the degree of the inhibitory activity was correlated with the level of nitrite (NO2-) in the serum. When L1210 cells were co-cultured with peritoneal macrophages from mice intraperitoneally injected with hM-CSF, the uptake of [3H]thymidine in L1210 cells was inhibited. The inhibition was abolished by the addition of NG-monomethyl-L-arginine, an inhibitor of NO2- synthesis, suggesting that the reactive nitrogen oxide intermediate is involved in hM-CSF-induced inhibition of L1210 growth.

Amino Acid Oxidoreductases↗
PubMed1995

Identification of macrophage colony-stimulating factor in human milk and mammary gland epithelial cells.

Human milk contains cellular and soluble host-protective components. Macrophages in human milk constitute a major cellular component in contrast to those in the peripheral blood. We have investigated a mechanism of local expansion of macrophages in human milk. First, biologically active macrophage colony-stimulating factor (M-CSF) was identified in human milk. The maximal concentrations of M-CSF in human milk were 10- to 100-fold higher than those in the serum. The concentrations of M-CSF in the milk had no correlation with those in the serum. M-CSF was immunohistochemically detected in the epithelial cells of the ducts and alveoli of the mammary gland. In situ hybridization study confirmed the local synthesis of M-CSF in the mammary gland epithelial cells. A possible role of female sex steroids was discussed in the regulation of M-CSF production by mammary gland epithelial cells.

Adult↗
PubMed1995

[A case of pulmonary tuberculosis associated with tuberculous fistula of anus].

A 39-year old male visited the hospital complaining of perianal pain, swelling and redness. Under the diagnosis of an anal abscess, drainage was performed repeatedly. As the wound failed to heal and fistulae were detected, excision of entire tract was performed. On histopathological examination of the resected fistulae, caseous necrosis, Langhans giant cells, and epithelioid cell infiltration were found and diagnosed as anal tuberculosis. Chest X-ray showed cavitary lesion with infiltrative shadow in right upper lobe. Acid-fast bacilli were positive in sputum, and the diagnosis of pulmonary tuberculosis was confirmed. Anti-tuberculosis therapy was immediately started with good response to treatment. As tuberculosis of anal region is so rare recently and there is no characteristic clinical picture, it is very difficult to diagnose it pre-operatively. In some cases such as ours, pulmonary or other tuberculosis is accompanied with anal tuberculosis. Therefore, accurate diagnosis of anal tuberculosis is needed to find other tuberculosis early. As anal tuberculosis is rarely diagnosed correctly before operation on the basis of the clinical picture, the histopathological examination of the excised fistula is mandatory for the correct diagnosis of anal tuberculosis.

Adult↗
PubMed1995

Primary pulmonary lymphoma: relationship between clinical features and pathologic findings in 24 cases. The Japan National Chest Hospital Study Group for Lung Cancer.

To elucidate the relationship between the clinical features and pathologic findings of primary pulmonary lymphoma, we reviewed 24 patients with this disease. The pulmonary lymphomas were divided into four groups: (1) B-cell lymphoma composed of small to medium-sized lymphoid cells (19 cases); (2) B-cell lymphoma composed of large lymphoid cells (three cases); (3) T-cell lymphoma (one case); (4) malignant lymphoma of lymphomatoid granulomatosis (LYG) type (one case). Radiographs of the first group revealed a predominance of infiltration associated with ill-defined tumor margins upon gross pathology, corresponding histologically to lymphangitic spread. Air bronchogram and pleural tail or abutment were additional radiographic features. Characteristics of the second group were a nodule or mass evident on radiographs and well-circumscribed tumor margins upon gross pathology. Lack of air bronchogram was an another radiographic feature in this group. Seventeen patients in these two groups underwent complete resection of the tumors and survived without recurrence, whereas four received chemotherapy after biopsy and survived with disease. These results indicate that primary pulmonary B-cell lymphoma is a low-grade malignancy and that complete resection is the only therapy which leads to cure. In a single patient with T-cell lymphoma, the radiographic and pathologic features of the tumor were indistinguishable from those in the first group, but the patient had an unfavorable prognosis. We consider that, from a prognostic viewpoint, it is important to determine the T- or B-immunophenotype of the tumor cells for diagnosis of primary pulmonary lymphoma. The only patient in this series with pulmonary lymphoma of LYG type showed distinctive clinicopathologic findings. We consider that this uncommon disease should be separated from other types of primary pulmonary lymphoma.

Adolescent↗
PubMed1995

[Bronchopleural fistula following the use of automatic stapling devices for lung cancer].

We compared automatic stapling with hand suturing in the rate of bronchopleural fistula. Twenty two hundred forty one patients of 25 hospitals, who were performed lobectomy or pneumonectomy for lung cancer from the year of 1990 to 1992, were investigated about the occurrence of bronchopleural fistula. The rate of bronchopleural fistula following lobectomy were 0.9% (11/1,227 cases) in automatic stapling, and 1.1% (8/753 cases) in hand suturing; there was no difference. However, there was a higher rate of the fistula with the use of automatic stapling devices in pneumonectomy. The rate was 11.2% (11/98 cases) in automatic stapling, and 1.2% (2/166 cases) in hand suturing. Automatic stapling may lead to bronchopleural fistula in pneumonectomy. Moreover, addition of hand suturing to automatic stapling was thought to prevent the fistula.

Bronchial Fistula↗
PubMed1994

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↗
PubMed1994

Different cellular mechanisms of vasopressin receptor V1 and V2 subtype in vasopressin-induced adenosine 3', 5'-monophosphate formation in an immortalized renal tubule cell line, TKC2.

Vasopressin (VP) stimulates adenosine 3',5'-monophosphate (cAMP) formation in an immortalized renal tubule cell line, TKC2, which is derived from transgenic mouse harboring temperature-sensitive SV40 T-antigen gene. VP (10(-8) M)-induced cAMP formation was significantly attenuated by either non-peptide vasopressin receptor V1 or V2 subtype antagonist, OPC-21268 (10(-8) and 10(-6) M) or OPC-31260 (10(-8) and 10(-6) M), respectively, and it was completely abolished by combination of both agents (10(-6) M). VP (10(-8) M) also induced an increase in cytosolic free Ca2+ and prostaglandin (PG) E2 synthesis, both of which were significantly inhibited by OPC-21268 (10(-8) M), but not by OPC-31260 (10(-6) M). Either OPC-21268 (10(-8) M), depletion of extracellular Ca2+ or inhibition of cyclooxygenase attenuated both VP-induced PGE2 synthesis and cAMP formation. In conclusion, both V1 and V2 receptors can stimulate cAMP formation. V1 receptor, however, stimulates cAMP formation via Ca(2+)-dependent PGE2 synthesis, whereas V2 receptor may stimulate it directly.

Animals↗
PubMed1994

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↗
PubMed1994

Roles for integrin very late activation antigen-4 in stroma-dependent erythropoiesis.

Adhesion molecules are required for development of hematopoietic stem and progenitor cells in the respective hematopoietic microenvironments. We previously showed that development of the erythroid progenitor cells is dependent on their direct adhesion to the stroma cells established from the erythropoietic organs. In this stroma-dependent erythropoiesis, we examined the role of adhesion molecules in erythropoiesis by blocking antibodies. The development of the erythroid cells on stroma cells was inhibited by anti-very late activation antigen-4 (VLA-4 integrin) antibody, but not by anti-VLA-5 antibody, although the erythroid cells express both VLA-4 and VLA-5. Whereas high levels of expression of vascular cell adhesion molecule-1 (VCAM-1) and fibronectin, ligands for VLA-4, were detected in the stroma cells, the adhesion and development of the erythroid progenitor cells were partly inhibited by the blocking antibody against VCAM-1. VLA-5 and fibronectin could mediate adhesion of the erythroid progenitor cells to the stromal cells, but the adhesion itself may not be sufficient for the stroma-supported erythropoiesis. The stromal cells may support erythroid development by the adhesion through a new ligand molecule(s) for VLA-4 in addition to VCAM-1, and such collaborative interaction may provide adequate signaling for the erythroid progenitor cells in the erythropoietic microenvironment.

Animals↗
PubMed1994

Primary culture of human leptomeningeal cells in serum-free medium.

Human leptomeningeal (LM) cells were grown in serum-free medium supplemented with insulin, transferrin and bovine serum albumin. The cultured cells maintained the polygonal morphology characteristic of leptomeningeal cells. Electronmicroscopic and immunofluorescence examinations revealed interdigitation of cell membranes, invagination of cytoplasm into the nucleus, specialized intercellular junctions and the presence of cytokeratin. These characteristics are consistent with previous reports characterizing LM cells. This serum-free culture system may facilitate the in vitro study of the leptomeninges.

Arachnoid↗
PubMed1994

Comparison of first-trimester transvaginal amniocentesis with chorionic villus sampling and mid-trimester amniocentesis.

Between August 1989 and December 1991, 356 patients underwent first-trimester transvaginal amniocentesis (10-12 weeks). The same number of patients referred in the same period for mid-trimester amniocentesis (14-21 weeks) was matched also for maternal age and indication. A third group consisted of the first 356 cases in which chorionic villus sampling (CVS) was attempted. The overall success rate was 99.7 and 100 per cent for early and mid-trimester amniocentesis, respectively, and 97.2 per cent for CVS. The mean harvesting time was 12.8, 11, and 7.9 days, respectively. The percentage of patients rescheduled was 3.4 per cent in first-trimester amniocentesis, 1.7 per cent in mid-trimester amniocentesis, and 6.2 per cent in the CVS group. The early (less than 2 weeks) pregnancy loss was 1.7 and 0.6 per cent in early and mid-trimester amniocentesis, respectively, and 1.7 per cent in CVS. The total pregnancy loss was 3.2, 0.9, and 2.9 per cent, respectively. The rate of preterm birth was 6.0, 5.2 and 6.9 per cent, respectively. The results indicate that CVS has the shortest procedure-result interval, but the highest rescheduling rate. First-trimester amniocentesis has a higher procedure and laboratory success rate but, until otherwise proved, mid-trimester amniocentesis is the most efficient and safest procedure.

Abortion, Spontaneous↗
PubMed1994

Sonographic presentation of Hirschsprung's disease. A case of an entirely aganglionic colon and ileum.

Prenatal sonographic presentation of Hirschsprung's disease has been considered non-specific and uncommon. This report presents a second-trimester fetus with an aganglionic colon and ileum diagnosed by the sonographic presentation of dilated fetal bowel loops, increased abdominal circumference, and mild polyhydramnios. The prenatal sonographic diagnosis of Hirschsprung's disease helped to expedite early neonatal treatment.

Adult↗
PubMed1994

Apoptosis is induced at nonpermissive temperature by a transient increase in p53 in cell lines immortalized with temperature-sensitive SV40 large T-antigen gene.

Hepatocyte (TLR2) and kidney tubule (TKC2) cell lines established from temperature-sensitive (ts) SV40 T-antigen gene transgenic mice not only were arrested in growth, but also exhibited cell death at nonpermissive temperature (39 degrees C). The cell death was determined to be caused by apoptosis from observations of nuclear fragmentation and DNA fragmentation. These cell lines contained relatively high levels of wild-type p53 which formed complexes with T-antigen at permissive temperature (33 degrees C), but after shift to a nonpermissive temperature, the inactivation of T-antigens led to the liberation of an abundance of p53 proteins from the complexes, apparently inducing apoptosis.

Animals↗
PubMed1994

Japanese doctors' preferred treatment choices for their hypothetical non-small cell lung cancer: how they would wish to be treated. National Chest Hospital Study Group for Lung Cancer.

We conducted a trial to clarify what Japanese clinical doctors think about the present status of therapy for non-small cell lung cancer, as well as to clarify which problems are still unresolved. One-hundred five Japanese doctors who treat lung cancer patients were asked how they would choose to be treated, if they suffered from non-small cell lung cancer. Six scenarios were presented and the doctors had to choose one treatment method for each of the six scenarios. Adjuvant chemotherapy or radiotherapy after complete resection, increase with progression of the pathological stage. Ninety-three per cent of Japanese doctors wanted surgery, even if mediastinal lymph node metastases were present. In the scenario of only one distant metastasis to the brain, 44% of doctors wanted surgery while 39% wanted chemotherapy and/or radiotherapy. In the scenario of multiple bone metastases, 33% wanted chemotherapy, 77% did not. It was concluded therefore that Japanese doctors choose surgery as the number one treatment modality when all lesions are considered resectable.

Adult↗
PubMed1994

The role of estrogen support during the luteal phase of in vitro fertilization-embryo transplant cycles: a comparative study between progesterone alone and estrogen and progesterone support.

OBJECTIVE: To evaluate the possible role for estrogen supplementation to the P luteal phase support of GnRH agonists (GnRH-a)- and hMG-induced IVF-ET cycles. SETTING: In vitro fertilization unit in a tertiary care university hospital. DESIGN: A prospectively randomized study. PATIENTS: One hundred consecutive patients undergoing ET after IVF were assigned into one of two luteal supplementation regimens. INTERVENTIONS: In all patients enrolled in the study, ovulation was induced using the midluteal regimen for pituitary down regulation with GnRH-a followed by follicular stimulation with hMG. The first group received IM P 50 mg/d, as luteal phase support, starting the day of ET. The second group received the same dosage of P, combined with oral E2 valerate, 2 mg/d. Serum levels of P and E2 were monitored every 4 days for 16 days after ET. MAIN OUTCOME MEASURES: Pregnancy rates (PRs) and live birth rates per ET. RESULTS: No significant difference in E2 or P levels throughout the cycle was observed between groups. Similar PRs per ET and the live birth rates were also observed between group A and B (28% versus 26.5% and 78.6% versus 76.1%, respectively). CONCLUSION: No advantage was found in the addition of E2 valerate to P luteal phase support of GnRH-a- and hMG-induced IVF-ET cycles.

Adult↗