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Biomedical subjects

S Takeuchi

Publications and source records attributed to S Takeuchi.

At least 289 records · Page 16Linked to original sources
PubMed1997

Cloning of the enomycin structural gene from Streptomyces mauvecolor and production of recombinant enomycin in Escherichia coli.

A genomic DNA library from the enomycin (ENM) producer, Streptomyces mauvecolor, was screened for the ENM structural gene (enm) by use of a segment of the phenomycin gene (phm) as the probe, and a plasmid, pENI, was constructed. By primer-walking along the insert, a 573 bp DNA sequence that contain an ORF corresponding to preENM was determined. The deduced amino acid composition of ENM was close to that previously reported (MIZUNO, S.; K. NITTA & H. UMEZAWA: Mode of action of enomycin, an antitumor antibiotic of high molecular weight. I. Inhibition of protein synthesis. J. Biochem. 61: 373 approximately 381, 1967). The producer cells expressed enm during an ENM-productive fermentation. An enm-expression plasmid, pENE 1, was constructed, with which E. coli AD202 was transformed. The transformant produced a fusion protein consisting of glutathione-S-transferase (GST) and ENM. The genetically engineered ENM (rENM) inhibited the growth of Hela cells in vitro. Comparison of the base sequence spanning enm with that spanning phm showed that the structural genes were conserved more extensively than were the flanking regions, though the genes were unlikely to be essential to the lives of the producers.

Amino Acid Sequence↗
PubMed1997

[A case of recurrent gallbladder cancer with marked response to arterial infusion chemotherapy and transarterial embolization].

A 50-year-old man with gallbladder cancer was treated by extended cholecystectomy and regional lymph node dissection. At 13 months after surgery, CEA showed high serum levels, and an enlarged liver tumor due to recurrence was demonstrated by computed tomography. After arterial infusion chemotherapy consisting of CDDP, epirubicin and 5-FU, the tumor size and serum level of CEA were significantly decreased. After this therapy and transcatheter arterial embolization, the liver tumor markedly responded and became undetectable. It was suggested that this therapy was effective for gallbladder cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[Malignant mesothelioma of the tunica vaginalis: a case report].

An 18-year-old man visited our hospital with a painless swelling of the left scrotal contents. Transscrotal ultrasonography revealed a hydrocele and a 10-mm nodular mass attached to the tunica vaginalis. Tumor resection and hydrocelectomy were performed because the intra-operative histological diagnosis of a frozen section did not reveal malignancy. However, since the postoperative pathological diagnosis was malignant mesothelioma, the left hemiscrotum was excised. He has been free of disease 15 months postoperatively.

Adolescent↗
PubMed1997

[Three cases of mediastinal neurogenic tumors originating from the intrathoracic vagal nerve].

Three cases of mediastinal neurogenic tumors originating from the intrathoracic vagal nerve is reported. Two of those is neurilemmomas. One tumor was located in the site to the branching point of the recurrence nerve. The tumor was enucleated. Postoperative hoarseness arose. Another tumor was located in the vagal nerve. The tumor was resected. One of those is neurofibromatosis in the vagus nerve with the axillary tumor. The tumors arose from the vagus nerve was resected. Careful follow-up are required in two patients.

Adult↗
PubMed1997

[Giant testicular tumor associated with scrotal gangrene: a case report].

A case of giant testicular tumor associated with scrotal gangrene is reported. A 33-year-old man had a swollen scrotum (15 cm) accompanied with necrosis and a foulodor. The tumor had invaded the scrotum, perineum and the left spermatic cord. Serum alpha-fetoprotein level was 15,487 ng/ml. The chest radiograph revealed multiple metastases. Bilateral high orchiectomies and local resection with a wide margin were performed. The tumor weighed 2.5 kg and the histopathological diagnosis was teratocarcinoma. He was treated with 3 courses of chemotherapy with cisplatin, etoposide and peplomycin. A second-look surgery revealed no viable cancer cells in the residual masses. The patient has been free of recurrence 4 months postoperatively.

Adult↗
PubMed1997

Prediction of postoperative decompensated liver function by technetium-99m galactosyl-human serum albumin liver scintigraphy in patients with hepatocellular carcinoma complicating chronic liver disease.

BACKGROUND: Preoperative technetium-99m galactosyl-human serum albumin (Tc-GSA) liver scintigraphy may predict postoperative decompensated liver function and its value has been investigated in patients having resection of hepatocellular carcinoma (HCC). METHODS: Hepatic uptake ratio of Tc-GSA (LHL15) was measured before operation in 30 patients. Postoperative complications were analysed retrospectively and compared with LHL15 values and other indicators evaluating hepatic function. RESULTS: The LHL15 of 22 patients without complications was 0.91 or more, compared with 0.90 or less in the eight patients who had complications. Multifactorial analyses showed that LHL15 and Child-Pugh grade significantly predicted postoperative complications (P < 0.0001 and P = 0.0111 respectively). LHL15 was a significant predictor of complications in patients with Child-Pugh grade B disease (n = 15, P = 0.0011). CONCLUSION: LHL15 was a reliable preoperative indicator of the risk of major postoperative complications in patients who had resection for HCC.

Aged↗
PubMed1997

[Severe acute cardiac failure caused by the combination of the aortic stenosis and sudden onset of the mitral chordae rupture].

The patient, who had an aortic stenosis, suddenly complicated with severe acute cardiac failure. The rupture of the mitral chordae tendineae was detected by the echocardiogram. Double replacements (aortic and mitral) were done immediately after the onset of chordae rupture. This condition, combination of aortic stenosis and sudden onset of chordae rupture, always results in severe heart failure which is explained by the combination of pressure and volume loading. Finally the emergent operation is believed to be an only solution for this situation.

Acute Disease↗
PubMed1997

Video thoracoscopic resection of neurogenic tumor in a superior-posterior mediastinum: three case reports.

Neurogenic tumors of the thorax can originate in any neurogenic structure within the chest. Surgical resection is considered the primary treatment of such tumors and usually is performed through a thoracotomy. Recently, using a new approach, we applied the technique of video thoracoscopic surgery to resection a posterior mediastinal tumor. In this paper, we report three patients with superior-posterior mediastinal neurogenic tumors in which the approach to the tumor is technically difficult. Cases 1 and 2 were a 26-year-old man and a 50-year-old asymptomatic man, respectively, and case 3 was a 45-year-old asymptomatic woman. The sizes of the three tumors were 3.0 x 2.5 x 1.8 cm (case 1), 6.0 x 4.0 x 2.0 cm (case 2), and 3.0 x 2.0 x 2.0 cm (case 3). In one case (case 2), minithoracotomy was added to video thoracoscopic surgery for adhesion to the spinal artery and intraspinal extension. A standard thoracotomy was avoided in all three cases. All patients had uncomplicated postoperative courses. Video thoracoscopic resection of a neurogenic tumor in the superior-posterior mediastinum may be a safe and useful approach with improved cosmetic results.

Adult↗
PubMed1997

[Resection of multiple thymoma: a case report].

A 74-year-old male, who had been treated for hypertension at the out-patient clinic, was admitted to our hospital because of an abnormal shadow on a chest radiograph. After diagnosis of thymoma by needle biopsy surgery was carried out on July 6, 1995, when an extended thymectomy along with removal of the entire tumor was done. During the surgery it was noticed that there was not one, but two independent tumors located in the anterior mediastinum, the upper left portion was growing from the level of the crania to the left brachiocephalic vein, whereas the lower right portion was growing towards the right thoracic cavity in front of the pericardium. Both tumors were encapsulated firmly, and connected to each other by scantly loose connective tissues. There was no continuity or sarring between the two tumors. Histologically both were diagnosed to be lymphocytic thymoma. We believe that this case is a good example of multiple thymomas and provides evidence of the potential multicentricity of thymoma. It is possible that extended thymectomy may be seeded for a complete resection of thymomas.

Aged↗
PubMed1996

Fas/APO-1-mediated apoptosis of human renal cell carcinoma.

We have investigated the Fas-mediated apoptosis of cultured human renal cell carcinoma OUR-10. OUR-10 cells express Fas antigen on their cell surface and showed apoptotic cell death by stimulation with anti-Fas agonistic antibody. Cell proliferation of OUR-10 was reduced to 62% by the addition of anti-Fas antibody. The cytotoxic effect of anti-Fas antibody on OUR-10 was augmented by the pretreatment of these cells with interferon-gamma, not with interferon-alpha or with interleukin-2. Flow cytometry demonstrated that preculture of Our-10 cells with interferon-gamma increased the cell surface Fas antigen. Immunohistochemical analysis of resected tissues from the patients with renal cancer revealed stronger expression of Fas antigen on the surface of cancer cells than that of normal cells. These data suggest that Fas may be one of the possible targets for a novel approach to human kidney cancer, and the efficiency of this Fas-mediated treatment for kidney cancer could be augmented by the treatment with interferon-gamma.

Apoptosis↗
PubMed1996

TEL/AML-1 dimerizes and is associated with a favorable outcome in childhood acute lymphoblastic leukemia.

Polymerase chain reaction-based screening of childhood acute lymphoblastic leukemia (ALL) samples showed that a TEL/AML1 fusion transcript was detected in 27% of all cases, representing the most common known gene rearrangement in childhood cancer. The TEL/AML1 fusion results from a t(12;21)(p13;q22) chromosomal translocation, but was undetectable at the routine cytogenetic level. TEL/AML1-positive patients had exclusively B-lineage ALL, and most patients were between the ages of 2 and 9 years at diagnosis. Only 3/89 (3.4%) adult ALL patients were TEL/AML1-positive. Most importantly, TEL/AML1-positive children had a significantly lower rate of relapse compared with TEL/AML1-negative patients (0/22 v 16/54, P = .004). Co-immunoprecipitation experiments demonstrated that TEL/AML-1 formed homodimers in vitro, and heterodimerized with the normal TEL protein when the two proteins were expressed together. The elucidation of the precise mechanism of transformation by TEL/AML1 and the role of TEL/AML1 testing in the treatment of childhood ALL will require additional studies.

Adolescent↗
PubMed1996

Intravascularly applied K(+)-channel blockers suppress differently the positive endocochlear potential maintained by vascular perfusion.

We studied the effects of several K+ channel blockers on the positive endocochlear potential (EP) of guinea pigs undergoing perfusion via the anterior inferior cerebellar artery. The EP level was reversibly suppressed by 50-60% in the presence of Ba2+ (2 mM), quinine (2 mM) or verapamil (1 mM) in the perfusate, but not significantly affected by tetraethylammonium (20 mM) or 4-aminopyridine (5 mM). Although the effective site(s) of these blockers at the cell level has not been located yet, these findings indicate an important role for a K+ conductance in the generation of the EP.

Analgesics, Non-Narcotic↗
PubMed1996

Primary effusion lymphoma in women: report of two cases of Kaposi's sarcoma herpes virus-associated effusion-based lymphoma in human immunodeficiency virus-negative women.

Recent molecular evidence suggests an association with a new herpes virus, Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8), and primary effusion lymphomas (PEL). PELs have a characteristic morphology, phenotype, and clinical presentation with malignant effusions in the absence of a contiguous solid tumor mass. Most cases of PEL have occurred in human immunodeficiency virus (HIV)-positive male patients who are coinfected with Epstein-Barr virus (EBV). This report describes two cases of PEL in HIV- and EBV-negative women. In one patient, a pleural cavity PEL was preceded by classic Kaposi's Sarcoma (KS) of the lower extremities. In the second patient, PEL developed in an artificial cavity related to the capsule of a breast implant. Both cases had the characteristic morphologic appearance of high-grade anaplastic/B-cell immunoblastic lymphomas, with loss of B-cell differentiation antigens, clonal immunoglobulin heavy chain gene rearrangements, and expression of activation antigen CD30. Both cases were negative for EBV, herpes virus simplex, and cytomegalovirus (CMV). DNA extracted from both lymphomas and skin KS specimen showed KSHV sequences by molecular analysis. This report expands the spectrum of KSHV-associated disease to include PEL in HIV-negative women.

Aged↗
PubMed1996

A possible involvement of melanocortin 1-receptor in regulating feather color pigmentation in the chicken.

The Extended black (E) locus on chromosome 1 acts within the melanocyte to regulate feather color pigmentation in the chicken. Several alleles exhibiting different pigmentation have been described and their phenotypes are similar to those of the murine extension locus which encodes melanocortin 1-receptor (MC1-R), the receptor for alpha-melanocyte-stimulating hormone (alpha-MSH). To investigate whether the MC1-R gene is responsible for E-locus function, we examined the structure of MC1-R in E-locus mutants by RFLP analysis and genomic DNA sequencing. In the most recessive allele (ey), which exhibits a uniformly red-yellow pigmentation, MC1-R was found to contain amino acid substitutions possibly causing functional deficiency. On the other hand, in the most dominant allele (E), which confers a uniformly black pigmentation, MC1-R possessed mutation responsible for a constitutively active MC1-R and resultant black coat color in mice. Our finding that the structure of MC1-R was affected by individual E-locus alleles strongly suggests that MC1-R is associated with the E-locus. Furthermore, since the same mutation of MC1-R was found in mice and chickens that exhibit the same pigmentation, it is possible that the regulatory mechanism of MC1-R function is shared in chickens and mammals.

Alleles↗
PubMed1996

Dielectric monitoring of rouleaux formation in human whole blood: a feasibility study.

In search of a method for detecting rouleaux formation in vitro, we studied the dielectric behavior of human blood under both agitated and stationary conditions. Among the parameters examined, relative permittivity ('dielectric constant') at 50-100 kHz was found to be a suitable measure of rouleaux growth, which has been difficult to quantify through conventional optical approaches. The electrical method presented here appears applicable to the kinetic analysis of rouleaux formation in undiluted whole blood.

Electric Conductivity↗
PubMed1996

Na+,K(+)-ATPase activity in the cochlear lateral wall of the gerbil.

We examined Na+,K(+)-ATPase activity in four regions of the gerbil cochlear lateral wall by measuring intracellular Na+ concentration ([Na+]i). The application of 1 mM ouabain and removal of external K+ caused a most striking increase in [Na+]i of the suprastrial fibrocytes, followed by the stria vascularis and the type II fibrocytes, but no detectable response in the type I fibrocytes. These results may imply the potency of the Na+,K(+)-ATPase activity. The high values of the resting [Na+]i in these cells under perilymph-like solution returned to the [Na+]i within physiological values after exposure to low-Na+ conditions similar to endolymph. Our results are interpreted in the light of recent morphological findings with regard to the roles in the secretion of K+ into endolymph of several cell types within the lateral wall.

Animals↗
PubMed1996

Kaposi's sarcoma-associated herpesvirus (KSHV or HHV8) in primary effusion lymphoma: ultrastructural demonstration of herpesvirus in lymphoma cells.

Recent molecular evidence suggests an association with a new herpesvirus, Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8), and primary effusion lymphomas (PELs). PELs have a characteristic morphology, phenotype, and clinical presentation, with malignant effusions in the absence of a contiguous solid tumor mass. We have established a cell line (KS-1) from a KSHV-positive human immunodeficiency virus (HIV)-negative patient with pleural cavity-based lymphoma that was passaged into triple-immunodeficient BNX mice. In contrast to cell lines from body cavity-based lymphomas derived from HIV-positive individuals that contain both KSHV and Epstein Barr viral genome, these cells contain only KSHV, allowing for uncontaminated virologic studies. Ultrastructural examination identified malignant cells with features of late differentiating B cells (immunoblasts). Cells with viral cytopathic effect contained typical 110-nm intranuclear herpesvirus nucleocapsids and complete cytoplasmic virions, confirming the association of PEL with KSHV.

Animals↗