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Biomedical subjects

J Tanaka

Publications and source records attributed to J Tanaka.

At least 559 records · Page 31Linked to original sources
PubMed1991

Sodium butyrate-inducible replication of human cytomegalovirus in a human epithelial cell line.

Replication of human cytomegalovirus (HCMV) in a human epithelial thyroid papillary carcinoma cell line (TPC-1) was restricted. However, pretreatment of these cells with 5 mM sodium butyrate (NaB) for 24 hr before infection enhanced both HCMV yield and infectious center titer to a similar level of that seen in human embryonic lung fibroblast cells. Immunofluorescence staining, gel electrophoresis, and Northern blot analysis revealed that TPC-1 cells are nonpermissive for expression of HCMV major immediate early (IE1) functions, but many of the cells become permissive after being treated with NaB. The presence of cycloheximide during NaB pretreatment of the cells efficiently diminished the stimulatory effect of NaB on expression of the IE1 gene. Therefore, it appeared that NaB induces the synthesis of a cellular protein(s) which apparently plays an important role in the conversion of nonpermissive cells to a permissive state for expression of this critical viral gene. Transient chloramphenicol acetyltransferase (CAT) assay experiments indicated that in TPC-1 cells the HCMV-CAT construct which contains the complete IE1 promoter regulatory region was expressed poorly, whereas a high level of CAT activity was detectable in the NaB-treated cells. Therefore, these results suggest that the enhancing effect of NaB on HCMV replication is expressed through some host cellular factor(s), and the HCMV IE1 promoter regulatory region is most likely to be the primary target of NaB action.

Antibodies, Monoclonal↗
PubMed1991

Neurotoxic effects of 2,5-hexanedione on growing peripheral nerve axons of rat fetuses.

Peripheral nerves of rat fetuses were used to investigate the potential neurotoxicity of 2,5-hexanedione (2,5-HD) on developing axons. Pregnant female Sprague-Dawley rats were injected subcutaneously with 680 mg/kg of 2,5-HD once a day from day 12 of gestation (GD12) through GD16. On GD20 live fetuses were removed from the uterus, and the sciatic nerves were examined morphologically. Upon electron-microscopy affected nerves showed axons which were aggregated and fused together; the number of large axons was increased, but there were no axons aggregated with neurofilaments.

Animals↗
PubMed1991

Immunohistochemical expression of P400 protein in Purkinje cells of sphingomyelinosis mouse.

Immunohistochemical expression of P400 protein, a glycoprotein localized to the Purkinje cell membrane, has been studied in the cerebellum of spm mouse using anti-P400 monoclonal antibody. The initial change observed in the Purkinje cells was a swelling of the cell body with distortion of the neurites; this occurred as early as 5 weeks of age. A significant, patchy loss of Purkinje cells started at 6 weeks before cerebellar signs became manifest. With progression of the disease the dendritic processes in the molecular layer showed a marked swelling, followed by irregular arborization and finally by disintegration. A few, heterotopic Purkinje cells were found in the subcortical white matter; this was interpreted as an indication that a disturbance in neuronal migration could be superimposed on the sphingolipid metabolic disorder. Additionally, P400-immunoreactive nerve cells were occasionally encountered in areas of the deep cerebellar nuclei and in the lateral vestibular nuclei of the pontine tegmentum. The number of P400-immunoreactive Purkinje cells correlated well with the percentages of the remaining Purkinje cells during the ages of 4 to 7 wks. At the late stage of 10 to 12 weeks almost all Purkinje cells had lost their P400-immunoreactivity. It is suggested that Purkinje cells that fail to express P400 protein may undergo an immunohistochemical degeneration of the plasma membrane.

Aging↗
PubMed1991

Comparison of endothelin-1 concentrations in normal and complicated pregnancies.

Endothelin-1 (ET-1) may be important in regulating vascular tone in humans. To understand the role of ET-1 during pregnancy, we measured the concentrations of plasma immunoreactive ET-1 in normal, toxemic (pre-eclamptic or eclamptic), and other complicated pregnancies. There were no significant differences between ET-1 concentrations in normal pregnancy and those in toxemic pregnancy, except in one case with IgA nephropathy and severe toxemia. There also was no significant difference between the ET-1 concentrations in pure toxemia of pregnancy compared with superimposed toxemia of pregnancy. Furthermore, there was no correlation between ET-1 concentrations, blood pressure, or renal function during toxemic pregnancy. Similarly, there were no significant differences between ET-1 plasma levels in normal pregnancies and other complicated pregnancies except for two cases in which much blood was lost due to uterine atony and abruptio placenta. Thus, plasma ET-1 concentrations showed no significant relationship to blood pressure or renal function during normal or toxemic pregnancy, and were not related to the type (pure or superimposed type), grade, or severity of toxemic pregnancy.

Adult↗
PubMed1991

Enzyme-induced aggregation and disaggregation of tumor cells via the cell surface glycocalyx in association with deoxyribonucleic acid.

Serine proteases cause aggregation of the rat ascites tumor cell lines AH-130, AH-109A and YS in vitro, and the tumor cell aggregates are dissolved by treatment with DNase I. We previously demonstrated that these events played a critical role in the augmentation or reduction of experimental blood-borne metastasis of these cell lines. In the present study, the ultrastructural features of this protease-dependent aggregation were analysed. Transmission and scanning electron microscopy revealed that after the protease treatment each tumor cell was surrounded by a thin membranous (sleeve-like) structure. This sleeve-like structure was stained with ruthenium red to an intensity similar to the cell surface of the control. Adjacent cells became attached to each other with microvilli via this fine structure. Immuno-electron microscopy revealed DNA antigen as dense patches on the sleeve-like structure or as faint and diffuse deposits on the outer surface of the cells by indirect immunoperoxidase staining using an anti-DNA monoclonal antibody. Both the sleeve-like structure and immunopositive deposits disappeared after treatment with DNase I. Neither cell viability nor the normal ultrastructure of their organelles was influenced by the enzyme treatment. These results indicate that serine protease-induced tumor cell aggregation is due to cellular contact via the sleeve-like structure, which probably originates from the cell surface glycocalyx in association with DNA molecules of unknown origin.

Animals↗
PubMed1991

Postoperative erythroderma with change of HLA phenotypes from heterozygotes to homozygotes: a report of two cases.

Fatal "postoperative erythroderma" (POE) developed in 2 patients treated with liver lobectomy and the transfusion of fresh blood. Their clinical features and skin-histological findings were indicative of acute graft-versus-host disease (GVHD). The HLA phenotypes of circulating lymphocytes of the 2 patients were heterozygous but became homozygous late in the clinical course and were identical with those of the blood donors. One of the patient's haplotypes was identical with the donor's homozygous haplotype. These findings suggest the mechanism of development of POE in apparently immunocompetent patients. The donor's T lymphocytes are histocompatible with the patient's tissues, are not rejected, and become engrafted. The patient's tissues are not histocompatible with the donor's, so that GVHD develops.

Blood Donors↗
PubMed1991

Inhibitory effects of non-steroidal anti-inflammatory drugs on superoxide generation.

Effects of non-steroidal anti-inflammatory drugs (NSAID: amfenac sodium, diclofenac sodium, indomethacin and ketoprofen) on the generation of superoxide anion (O2-) by isolated rat polymorphonuclear leukocytes (PMN) were studied spectrophotometrically using cytochrome c. The effects of these drugs were also studied on O2- production by the xanthine-xanthine oxidase and reduced nicotinamide adenine dinucleotide phosphate (NADPH)-NADPH oxidase systems. Amfenac sodium, at 0.1 mM, inhibited significantly O2- generation in rat PMN induced by opsonized zymosan. At 0.5 mM, diclofenac sodium and indomethacin inhibited the O2- generation in rat PMN. All of the above drugs slightly inhibited O2- production by the xanthine-xanthine oxidase system. On the other hand, O2- production by the NADPH-NADPH oxidase system was significantly inhibited by the addition of amfenac sodium, ketoprofen or indomethacin. These results suggest that non-steroidal anti-inflammatory drugs do not work as an O2- scavenger and block O2- production by the NADPH-NADPH oxidase system of rat PMN. It is concluded that amfenac sodium and the other drugs are able to inhibit granulocyte O2- production by blocking the activation of NADPH-oxidase.

Animals↗
PubMed1991

Participation of lipid peroxidation in rat pertussis vaccine pleurisy. III. Thiobarbituric acid (TBA) reactant and lysosomal enzyme.

Activity of lysosomal enzymes, such as N-acetyl-beta-D-glucosaminidase (NAG), was assayed in exudate on a rat model of Bordetella pertussis vaccine pleurisy. Thiobarbituric acid (TBA)-reactive substances (TBA.R) and superoxide dismutase (SOD) activity were then monitored in the exudate on the acute phase response in this inflammatory model. Retention of the exudate in the pleural space increased rapidly after the challenge, and the exudate volume at 24 h reached about three times the volume at 6 h. The activity of SOD at 6 h was shown to be higher than that at 24 h after the challenge, thus showing negative correlations with TBA-R levels and exudate volume. The levels of TBA.R rapidly increased and reached maximum values at 24 h. It was concluded that the above three parameters correlated to the acute phase response in this inflammatory model.

Acetylglucosaminidase↗
PubMed1991

Cycloleonurinin, a cyclic peptide from Leonuri Fructus.

From Leonuri Fructus, a cyclic peptide composed of twelve amino acid residues was isolated. The sequence of the residues was established by mass spectroscopy and by the use of a protein sequencer for the partial hydrolysates obtained by alpha-chymotrypsin.

Amino Acid Sequence↗
PubMed1991

[Aging and exocrine pancreatic function evaluated by the recently standardized secretin test].

The authors studied the relationship between aging and exocrine pancreatic function by the secretin test which was recently standardized by the Japanese Society of Gastroenterology. Pancreatic juice was collected at 10 min intervals for 60 minutes after a bolus intravenous injection of secretin (Secrepan, Eisai Co., Ltd., 100 U/body) through a quadruple-lumen doudenal tube equipped with double balloons. Exocrine pancreatic function was evaluated by three parameters: secretory volume, maximal bicarbonate concentration or bicarbonate output, and enzyme (amylase and lipase) output. Control subjects consisted of 65 outpatients presenting with mild vague abdominal symptoms who fulfilled the following three criteria: 1) good general condition with no known diseases; 2) no abnormality in the liver, bile duct, pancreas, kidney and metabolism judged from blood chemistry, urine and stool analysis, upper GI series, abdominal ultrasonography (US), and endoscopic retrograde cholangiopancreatography (ERCP); 3) alcohol consumption less than 25 g/day. Control subjects were divided into three groups: 15 subjects below 40 years of age (group A), 32 subjects from 40 to 65 years (group B), and 18 subjects of 65 years and above (group C). Nineteen patient with chronic pancreatitis were also studied. The group C showed significantly lower values in secretory volume, bicarbonate output, and enzyme output than group A and B. Enzyme output showed a gradual decrease with aging. However, secretory volume and bicarbonate output showed a gentle convex curve with a peak around age 40 and a rather steep down-slope after late 50s. The degree of the decrease was significantly more marked in volume and bicarbonate output than in enzyme output in group C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Peripheral neuropathy in two children with mitochondrial encephalomyopathy].

Peripheral neuropathy (PN) associated with mitochondrial encephalomyopathy (MEM) has been reported in adult patients, while children with both conditions are rare. Electrophysiological and pathological studies disclosed evidence of PN in a 3-year-old girl and an 8-year-old boy with MEM. In both patients, peripheral nerve conduction velocities were reduced, while amplitudes of evoked potentials were normal. No ragged red fibers were found in the biopsy muscle, while most of the muscle fibers showed poor activity with histochemical staining for cytochrome c oxidase (CCO). Biochemical studies revealed deficiency of CCO in both cases. In the latter patient, CCO activity was also absent in the intramuscular peripheral nerve using CCO staining, and histopathological studies of the sural nerve revealed a marked decrease in the number of large myelinated fibers and an unusual accumulation of the mitochondria in the Schwann cell cytoplasm. These results may support the hypothesis that a common pathogenesis exists in both peripheral nerve and muscle due to mitochondrial dysfunction.

Age Factors↗
PubMed1991

[Exercise induced precordial T wave normalization associated with U wave inversion in detection of left anterior descending artery stenosis].

Although normalization of inverted T wave is not an uncommon finding during exercise tests, it's clinical significance is still unclear. Exercise 12-lead electrocardiograms (ECGs) were recorded by using Master's 2-step or ergometer. T wave normalization in the anterior chest leads was found in 20 patients with, and 14 patients without coronary artery disease (CAD). Coronary angiography and/or exercise Tl-201 myocardial imaging were also performed in every patient. Exercise-induced T wave normalization was defined as "inverted T wave at rest becoming upright during exercise". ST segment, T and U wave amplitudes were measured before and immediately after exercise. 1) All of the 20 patients (100%) with CAD demonstrated critical stenosis of the left anterior descending artery (LAD). 2) ST deviation was noted in none of the 14 patients (0%) without CAD, and in only 4 of the 20 patients (20%) with CAD. 3) T wave amplitude increased equally in patients both with and without CAD. 4) Exercise-induced U wave inversion was found in 16 of the 20 patients (80%) with CAD, whereas it was found in only 1 of the 14 patients (7%) without CAD. 5) The sensitivity of "U wave inversion" in detection of LAD stenosis was 80%, and the specificity was 93%. We conclude that exercise-induced T wave normalization associated with U wave inversion in anterior chest leads is highly indicative of the specific presence of critical LAD stenosis.

Adult↗
PubMed1991

Intracavitary irradiation treatment via the inferior vena cava for caudate lobe invasion in hepatic hilar bile duct cancer.

Cancer invasion to the caudate lobe of the liver is considered an important prognostic factor in hepatic hilar bile duct cancer, and caudate lobectomy is required in cases with massive invasion. In many cases, however, the invasion is difficult to confirm even at intraoperative examination. As the caudate lobe is close to the inferior vena cava, it can be irradiated by a source in the inferior vena cava. In this paper, intracavitary irradiation of the caudate lobe via the inferior vena cava is proposed instead of resection for possible, but not confirmed, invasion. In experiments on dogs, intracavitary irradiation was performed by remote after-loading using 60Co at a dose of 20 and 300 Gy via the inferior vena cava. The radiation is so highly concentrated on the designated target that an anticancer effect can be expected. No noteworthy side effects were observed by functional and morphological studies after 20 Gy irradiation. This treatment has been applied clinically, with favorable results. This treatment modality is a non-surgical caudate lobectomy aimed at avoiding useless, and potentially hazardous, resection.

Animals↗
PubMed1991

[Simultaneous bilateral renal pelvic tumors: a case report].

A case of simultaneous bilateral renal pelvic tumors is reported. A 64-year-old man with the chief complaint of gross hematuria and left flank pain was admitted. Clinical investigations revealed a tumor in the right pelvis and ureter, and another tumor in the left renal pelvis. The right ureteral tumor had invaded the bladder. Right nephroureterectomy, total cystectomy, left partial pyelectomy and ureterocutaneostomy were performed. By pathological examination, right renal pelvic and ureteral tumors were non-papillary transitional cell carcinoma, grade 3, pT4, and the left renal pelvic tumor was papillary transitional cell carcinoma, grade 2, pT1. To our knowledge, this is the 16th case of simultaneous bilateral urothelial tumors of the upper urinary tract in Japan.

Carcinoma, Transitional Cell↗
PubMed1991

Cytoplasmic crystalloids in the periodontal tissue of beige mice.

The periodontal tissue of beige mice has been examined by electron microscopy. Specimens of the periodontal tissue from the right mandibular first molars of 10 male beige (bg/bg) and 5 male non-beige (bg/+, controls) mice, were fixed in a mixture of glutaraldehyde and paraformaldehyde, and then decalcified in EDTA. After fixation in osmium tetroxide, the specimens were dehydrated and embedded in epon resin. Ultrathin sections were then stained with uranyl acetate and lead citrate, and observed by electron microscopy. A larger number of cytoplasmic crystalloids were seen in the lysosomes of the histiocytes of the beige mice than in the non-beige mice. These cytoplasmic crystalloids showed striation structures composed of linear densities that were oriented longitudinally, transversely, and obliquely, with about a 4-nm periodicity. The periodontal tissue of the beige mice contained several cells with numerous cytoplasmic crystalloids, whereas there were few cells with fewer crystalloids in the non-beige mice.

Animals↗
PubMed1991

[Left ventricular hypertrophy secondary to systemic hypertension: its effect on coronary hemodynamics].

To clarify the characteristics and possible causes of phasic blood velocity patterns in pressure overload hypertrophy, we measured blood flow velocities in the left anterior descending coronary arteries in 16 patients with left ventricular hypertrophy secondary to systemic hypertension. These measurements were made with a 20MHz Doppler catheter. All patients had normal coronary arteriograms. The blood flow velocity patterns were characterized by the decrease in the rise of early diastolic inflow velocity. Prolongation in the time from the onset of diastole to peak velocity (TDPV) correlated with the degree of left ventricular hypertrophy. TDPV was prolonged in proportion to the increase in the peak left ventricular systolic pressure and left ventricular ejection fraction. The flow reserve calculated from the ratio of the diastolic mean velocity after the intracoronary injection of papaverine to the resting flow showed a trend toward the decrease proportional to the prolongation in TDPV due to an increase of wall thickness. In conclusion, preceding systolic vascular compression and systolic vascular strain can be factors causing early diastolic inflow disturbance in left ventricular hypertrophy secondary to hypertension. The decrease of coronary reserve may partially be attributable to the decrease in the rise of early diastolic inflow velocity.

Adult↗
PubMed1991

[Cell kinetic studies on the gallbladder epithelium in patient with anomalous arrangement of pancreatobiliary duct].

It is well known that the patients with anomalous arrangement of pancreatobiliary duct (AAPBD) are combined with biliary tract cancer. To clarify possible carcinogenesis of the gallbladder with AAPBD, DNA analysis of the gallbladder epithelium was performed in control (9 cases), AAPBD (26), gallbladder cancer confined in mucosa (10) and noncancerous epithelium around the gallbladder cancer (21). The mean values of DNA score, as already reported by us as an indicator of cell kinetics, were 12.1 (control), 27.2 (AAPBD, Type a), 13.3 (AAPBD, Type b), 14.8 (noncancerous epithelium around cancer) and 77.2 (gallbladder cancer confined in mucosa). The values of DNA score in the epithelium of AAPBD (Type a) showed significantly high level, which was next to that of cancer. Type a AAPBD may be supposed to have potential malignancy because of its accelerated cell cycle. But as Type b AAPBD without accelerated cell cycle combines cancer at least as often as Type a, further studies should be performed to reveal the relationship between cell cycle and malignancy.

Bile Ducts↗