PubMed Health⌕ Search

Biomedical subjects

S Kaneko

Publications and source records attributed to S Kaneko.

At least 19 recordsLinked to original sources
PubMed1992

Sequence comparisons for a hepatitis C virus genome RNA isolated from a patient with liver cirrhosis.

The nucleotide (nt) sequence was determined for an isolate of hepatitis C virus (HCV) derived from cirrhotic tissue of a patient with hepatocellular carcinoma. The 9408-nt sequence (EMBL Acq. No. X61596) showed homology of 90.7-91.4% on the nt level, as compared to two Japanese isolates from patients with a high titer of serum transaminase, 78.4-78.8% to those obtained in the United States, and 65.0% to that from an asymptomatic Japanese carrier. The phylogenetic tree of the six isolates classified them into three groups.

Genome, Viral↗
PubMed1992

Apolipoprotein E1 Lys-146----Glu with type III hyperlipoproteinemia.

During the screening of samples obtained from 5 individuals with type III hyperlipidemia, we identified a variant of apolipoprotein (apo) E which exhibited a discrepancy in apo E phenotype showing the E3/E1 isoform on isoelectric focusing (IEF) analysis and E3/E3 on gene analysis. Sequence analysis of the DNA of the proband that was amplified by PCR and subcloned, revealed a single substitution of one lysine (AAG) for one glutamic acid (GAG) at position 146, thereby adding two negatively charged units to apo E3. This defect had been described only for apo E1 to date (Mann et al. (1989) Clin. Res. 37, 520A (abstract)). In this case, PCR-mediated site-directed mutagenesis was used to identify the structural alterations forming the abnormal E1 genotype in the proband's family. Purified apo E1 Lys-146----Glu showed less than 10% of binding activity to apo B, E receptor on human skin fibroblasts compared with apo E3. This substitution demonstrates that Lys-146 is essential for the binding of apo E to the receptor.

Adult↗
PubMed1992

Involvement of postsynaptic G proteins in hippocampal long-term potentiation.

The possible involvement of postsynaptic guanosine 5-triphosphate (GTP)-binding proteins (G proteins) in long-term potentiation (LTP) was studied in rat hippocampal slices, using whole-cell recording techniques. The inclusion of guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) or guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) in the recording pipette significantly reduced or abolished the baclofen-induced hyperpolarization of pyramidal neurons, which indicates uncoupling of the signal transduction from G protein-coupled receptors by these compounds. Both GDP beta S and GTP gamma S significantly attenuated the magnitude of LTP in the fimbria-CA3 synapses, but not in the mossy fiber-CA3 synapses. GTP gamma S did not attenuate LTP in the Schaffer-CA1 synapses. The effects of guanine nucleotide analogs on fimbrial LTP were reversed by postsynaptic depolarization during high frequency stimulation. These results suggest that postsynaptic G proteins may be involved in the generation of LTP in the fimbrial synapses, possibly by affecting membrane depolarization during high frequency afferent activation.

Animals↗
PubMed1992

Expression of renal organic cation transporter in Xenopus laevis oocytes.

The expression of the organic cation transport system of rat renal proximal tubules has been studied in Xenopus laevis oocytes injected with poly(A)+ RNA from the rat renal cortex. The effectiveness of the technique was confirmed by examining expression of the Na+/D-glucose co-transporter. Compared with water-injected and non-injected oocytes, the injection of total poly(A)+ RNA resulted in about a 3-fold increase in tetraethylammonium (TEA) uptake activity. TEA uptake by poly(A)(+)-RNA-injected oocytes was time-dependent and was inhibited by cimetidine and HgCl2, but not by p-aminohippurate. After size-fractionation on a sucrose density gradient, a 1.4-2.4 kb poly(A)+ RNA fragment was identified that expressed the organic cation transport system in oocytes. These results demonstrate that the renal organic cation transporter was expressed in oocytes and that this expression system can provide an effective assay procedure for cloning of the organic cation transporter.

Animals↗
PubMed1992

Metabotropic responses to acetylcholine and serotonin of Xenopus oocytes injected with rat brain mRNA are transduced by different G-protein subtypes.

To assign the GTP-binding protein (G-protein) subtype involved in the signal transduction from exogenous receptors to phospholipase C in the Xenopus oocyte translation system, antisense DNA complementary to rat G-protein alpha-subunit mRNA was designed and injected together with rat brain poly(A)+ RNA. Current response of mRNA-injected oocytes to acetylcholine (ACh) was suppressed dose-dependently by a co-injection of Gil alpha-antisense DNA, but response of the same oocytes to serotonin (5-HT) was not inhibited. In the oocytes co-injected with Go alpha-antisense DNA, the 5-HT response was more effectively suppressed than the ACh response. These results suggest that Go alpha but not Gil alpha intermediates brain 5-HT1C receptor function, and in contrast, muscarinic receptors derived from rat brain utilize Gil alpha rather than Go alpha to activate phospholipase C.

Acetylcholine↗
PubMed1992

Morphological differences between hepatocellular carcinoma and hepatocellular carcinomalike lesions.

In an attempt to provide a quantitative basis for differentiation between well-differentiated hepatocellular carcinoma and hepatocellular carcinomalike lesions (focal nodular hyperplasia, regenerative nodular hyperplasia and hepatocellular adenoma), histopathological and morphometrical analyses were performed on 208 cases of various liver diseases with the aid of an image analyzer. As practical indicators for hepatocellular carcinoma, the following six morphometrical features were established: (a) nuclear shape factor of less than 0.93, (b) coefficient of variance of nuclei of more than 5%, (c) average width of trabecular cords greater than three cells, (d) nucleocytoplasmic ratio increased to more than 0.3, (e) cellular density of more than 40 liver cells and (f) individual nuclear dimension larger than 50 microns2. The manifest categories increased with dedifferentiation of cells in hepatocellular carcinoma; the number and degree of cellular and structural atypia became more prominent. Data were analyzed statistically by two multivariate analyses. Logistic analysis was able to correctly separate hepatocellular carcinoma from conditions that were not hepatocellular carcinoma, including hepatocellular carcinomalike lesions. The incidence of 13 descriptive histopathological findings such as fibrous capsule, portal triads and clear-cell clusters were also compared in hepatocellular carcinomalike lesions and hepatocellular carcinomas graded according to Edmondson's classification. Presence of a fibrous capsule, portal triads, mosaiclike patterns and tumor vessels showed statistical differences between hepatocellular carcinomalike lesions and well-differentiated hepatocellular carcinoma by the chi 2 test (p less than 0.005).

Autopsy↗
PubMed1992

Clearance of HBsAg in seven patients with chronic hepatitis B.

The natural history of chronic hepatitis B patients who spontaneously cleared serum HBsAg was investigated. A total of 351 patients with chronic hepatitis B were observed in our hospital for at least 3 yr. Seven of these patients became HBsAg negative during the follow-up period. HBsAg disappeared within 6 mo (range = 11 to 169 days, mean = 70 days) after acute elevation of ALT. ALT levels as high as 500 IU were found in three patients, whereas such elevation was not demonstrated in the other four patients. After the disappearance of HBsAg, ALT levels returned to normal in all patients. With one exception, all patients seroconverted to antibody to HBsAg; however, hepatitis B virus DNA remained detectable in serum using the polymerase chain reaction in five patients. The titer of percent inhibition of antibody to HBcAg gradually decreased to less than 70% when a 1:200 dilution of the serum of six patients was used. Four of the patients had active liver disease develop: two had chronic active hepatitis and two had cirrhosis. Three of these four patients subsequently had hepatocellular carcinoma develop. These findings suggest that patients may suffer complications of chronic hepatitis even after normalization of transaminase activities and after the clearance of HBsAg. Thus hepatitis B virus should be considered as a possible factor associated with hepatocellular carcinoma even in the absence of HBsAg, particularly if serum hepatitis B virus DNA persists.

Base Sequence↗
PubMed1992

Quantitation of hepatitis C virus RNA by competitive polymerase chain reaction.

Since the amount of hepatitis C virus (HCV) RNA might be correlated with the degree of severity of hepatitis and response to treatment, quantitation of HCV RNA in serum was established using competitive polymerase chain reaction (PCR). Known amounts of a plasmid containing HCV-cDNA were co-amplified with a standard dilution series of a competitive template which shared the primers' sequences but differed from the wild type cDNA in having a deletion. Accurate quantitation was obtained by comparing the amount of both products. Quantitation of serum HCV RNA was carried out in two patients' serum samples which were also used to infect chimpanzees. The concentration of HCV RNA in these two sera was calculated to be 1 pg/ml (non-infectious at 10(-3) dilution) and 1-10 pg/ml (infectious at 10(-5) dilution). The procedure was subsequently used to analyze serial changes in serum HCV RNA in three patients who were treated with alpha-interferon. During treatment, the levels of alanine aminotransferase showed a significant decrease in all patients and the amount of HCV RNA fell from 1 fg/ml, 1 pg/ml, and greater than 10 pg/ml to 0.1 fg/ml, 100 fg/ml, and 1 pg/ml, respectively. The decrease in the amount of HCV RNA after treatment was related to the initial amount of serum HCV RNA. These results suggest that quantitation of HCV RNA may be useful not only for understanding the course of HCV infection but also for evaluating treatment for HCV infection.

Base Sequence↗
PubMed1992

Detection and separation of some arginine amidases including tissue kallikrein from human seminal plasma.

A plasminogen/plasmin like substance (AHSAA-1), with affinity to lysine column was separated from DEAE-cellulose adsorbed human seminal plasma. Two forms of acidic arginine amidase with different affinities to LBTI (AHSAA-2) and aprotinin columns (AHSAA-3) were separated from the DEAE-cellulose adsorbed preparation and AHSAA-3 was identified as tissue kallikrein. Two basic arginine amidase preparations having affinity to LBTI (BHSAA-1) and aprotinin column were also separated from the CM-cellulose adsorbed human seminal plasma. Three basic arginine amidases with different molecular mass (BHSAA-2 to 4) were separated by Cellulofine GCL-2000 gel filtration from aprotinin adsorbed material and some of their properties were examined.

Amino Acid Sequence↗
PubMed1992

Surgically resected lung cancer in young adults.

Twenty-two patients, 40 years old or younger, were surgically treated for lung cancer between 1974 and 1989. The male to female ratio was 1.2:1. Ten patients were symptomatic, with the average duration of symptoms being 3.6 months. There were 13 patients with adenocarcinoma and 9 patients with large cell carcinoma. In terms, of postoperative stages, 5 patients were classified in stage I, 10 in stage IIIa, 5 in stage IIIb, and 2 in stage IV. Complete resection was performed in 14 patients, incomplete resection in 6, and exploratory thoracotomy in 2. The 3-year survival rate after complete resection was 66.2% in young patients, which was not significantly different from the 65.2% 3-year survival rate in older patients. There was no significant difference between the young and older groups according to histological cell type and TNM staging. In cases of incomplete resection or exploratory thoracotomy, 4 of 8 patients had been alive more than 2 years after operation. These results suggest that a long-term survival in the young patients is expected to be almost the same as that in the older patients after either complete resection or incomplete resection.

Adenocarcinoma↗
PubMed1992

Sclerosing hemangioma of the lung: radiographic and pathological study.

The clinical, radiographic, and pathological features of 10 patients with sclerosing hemangioma of the lung seen between 1974 and 1990 were reviewed. The incidence of sclerosing hemangioma was 22.2% of benign tumors surgically resected during that time. There were 2 male and 8 female patients aged 15 to 77 years at operation, and 9 patients were asymptomatic. All 10 patients had a solitary tumor with a well-defined homogeneous round or oval shadow on chest roentgenograms. Chest computed tomography revealed a homogeneous soft-density mass in 4 patients and a low-density portion within the tumor because of a cystic change in 1 patient. Microscopically, 5 patients had a preponderantly solid pattern, 3 had a preponderantly papillary pattern, and 1 patient had a preponderantly sclerotic pattern. One patient had an equal mixture of solid and papillary patterns. Nine of the 10 tumors consisted of a mixture of at least three of the four major patterns. Regarding treatment, thoracotomy is indicated for a definite diagnosis. If a benign tumor is suspected at operation, an intraoperative frozen section is recommended. Once the diagnosis has been established as sclerosing hemangioma, a limited resection is indicated.

Adolescent↗
PubMed1992

Effects of zonisamide on extracellular levels of monoamine and its metabolite, and on Ca2+ dependent dopamine release.

The effects of zonisamide (3-sulfamoylmethyl-1,2-benzisoxazole), a novel anticonvulsant, on extracellular levels of monoamine and its metabolite in the striatum and hippocampus, and Ca2+ dependent monoamine release in the striatum of freely moving rats were studied by microdialysis. Zonisamide increased dopamine, homovanillic acid and 5-hydroxyindoleacetic acid, and decreased 3,4-dihydroxyphenylacetic acid in the rat striatum. However, zonisamide showed no effect on Ca2+ dependent dopamine release in the rat striatum. In the hippocampus, zonisamide increased dopamine, homovanillic acid, serotonin and 5-hydroxyindoleacetic acid and decreased 3,4-dihydroxyphenylacetic acid. The present results suggest that zonisamide facilitates dopaminergic and serotoninergic neurotransmission but does not affect Ca2+ dependent dopamine release within therapeutic plasma concentrations.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1992

A case of ectopic opening of vasa deferentia into müllerian duct cyst.

We report very rare case in which the vasa deferentia entered a large Müllerian duct cyst in a 4-month-old infant. The presenting findings were lower abdominal mass and the complaint of urinary retention. A computed tomography scan of the pelvis showed a monolocular cystic mass between the bladder and the rectum. Surgical removal of the cyst was done because the mass increased in size and both hydronephroses and hydroureters were getting worse despite the use of antibiotics. The patient has no urological difficulty after the operation. This case was characterized as follows: the cyst was located on the midline, the vasa entered the cyst directly, the size of the cyst was large, and it was not associated with other malformations of the genitourinary system.

Choristoma↗
PubMed1992

Pulmonary tuberculoma and indications for surgery: radiographic and clinicopathological analysis.

Tuberculomas of the lung are one of the more common lesions presenting a solitary pulmonary nodule, roentgenographically. We treated 36 patients with such nodules and describe here the radiologic-pathologic correlations and surgical treatment. In 21 patients, lung cancer was suspected preoperatively, based on radiographic findings of an ill-defined margin, pleural indentation and spicular radiation. Histologically, the tuberculous granuloma proliferated in the alveolar septa of the surrounding normal lung, often seen as a spicular radiation resembling lung cancer. In eight patients, tuberculoma was suspected because of radiographic findings of calcification and satellite nodules, and anti-tuberculous chemotherapy was prescribed for a few months. As this treatment was ineffective, surgical resection had to be done. Postoperative complications were nil and all of these patients are doing well at the time of preparation of this report. Anti-tuberculous chemotherapy was prescribed for 28 of 36 patients, postoperatively. We believe that surgical intervention is required for selected patients.

Adult↗
PubMed1992

Adenosquamous carcinoma of the lung. Clinicopathologic and immunohistochemical features.

Adenosquamous carcinomas (ASC) of the lung comprise only 1.8% of all pulmonary cancers. Eleven patients with this disease (6 men and 5 women; mean age, 62 years [range, 51 to 78 years]) were treated. On the basis of pathologic and immunohistochemical evidence, the tumors were separated into three groups: five ASCs of predominantly glandular type, which may originate from squamous metaplasia in a preexisting adenocarcinoma; three mixed type ASCs, possibly derived from the transition of undifferentiated carcinoma to two different elements; and three predominantly squamous type ASCs resembling high-grade muco-epidermoid carcinoma. The 5-year survival rate of 35% for patients with ASCs was the same as that for patients with other nonsmall cell carcinomas. For two patients with ASCs of the predominantly glandular type and for one with the mixed type, resection was incomplete because of extensive local disease. All tumors of the predominantly squamous type could be excised completely. However, differences in the malignant potential of these three types of ASCs are still controversial.

Adenocarcinoma↗
PubMed1992

Subjective side effects of mianserin in relation to plasma concentrations of mianserin and desmethylmianserin.

The main purpose of the present study was to examine the possibility that plasma concentrations of mianserin and its metabolite, desmethylmianserin, might be predicted by recording subjective side effects. In 44 depressed patients, subjective side effects during 3 weeks of treatment with 30 mg of mianserin were evaluated by the UKU Side Effect Rating Scale, and their relationships to plasma concentrations of mianserin and desmethylmianserin were analyzed. There was no significant relationship between plasma concentrations of these compounds and the occurrence of mianserin-induced side effects, except for dryness of mouth during week one. Our study, therefore, suggests that it is difficult to predict plasma concentrations of mianserin and desmethylmianserin based on the occurrence of subjective side effects.

Adult↗
PubMed1992

A novel glial growth inhibitory factor, gliostatin, derived from neurofibroma.

Neurofibroma tissue was investigated for the presence of glial growth modulators that would suppress the proliferation of glial cells. A novel endogenous polypeptide inhibitor of proliferation and DNA synthesis in glial cells, gliostatin, was purified from the extracts of neurofibroma by a procedure comprising dye and anion-exchange column chromatography, and HPLC. A monoclonal antibody raised against partially purified gliostatin showed no cross-reactivity with known cytokines, but adsorbed the growth inhibitory activity of gliostatin and immunochemically visualized the putative gliostatin bands on western blot analyses. Although the product showed an apparent M(r) of 100,000 accompanied by an inhibitory activity on gel filtration column chromatography, it migrated at a lower apparent M(r) of 50,000 under the reducing conditions on western blotting, indicating that a homodimeric structure of native gliostatin consisted of 50-kDa subcomponents. Gliostatin was a potent growth inhibitor acting at nanomolar concentrations against all glial tumor cells and glia maturation factor-stimulated astroblasts, but not neuronal cells.

Animals↗