Biomedical subjects
Publications and source records attributed to M Kanoh.
Immunochemical relationships between salt-soluble proteins (albumins plus globulins) from buckwheat and indigo seeds were shown by immunoblot and immunodiffusion analyses using rabbit antisera raised against buckwheat globulins. These antigenic crossreactivities were roughly consistent with their polypeptide components judged by two-dimensional electrophoresis and SDS-PAGE analyses.
A case of ruptured dissecting aortic aneurysm (DeBakey IIIb) associated with the right sided aortic arch and anomalous course of the left branchiocephalic vein was reported. A sixty-nine-year-old female suddenly had the severe back pain and soon fell into shock. The diagnosis of a ruptured dissecting aortic aneurysm associated with the right sided aortic was obtained on CT scanning. CT films also showed the left brachiocephalic vein behind the ascending aorta. Emergency operation was performed through median sternotomy and left thoracotomy. The descending aorta, forming an aneurysm with the aberrant subclavian artery, prominently protruded far to the left, and was located behind the trachea and the esophagus. Extra-anatomical bypass grafting was performed between the ascending aorta and the distal descending aorta. The patient eventually died of multiple organ failure on the 11th day after operation. These findings were confirmed by autopsy. A rare vascular anomaly with aortic dissection was reported, and a surgical approach to that lesion was discussed.
A 15-year-old boy with proteinuria and hematuria is reviewed in this study. He was first found to have urinary abnormalities at the age of 13 years, and his renal function was exacerbated for a short duration. Renal biopsy was performed to make a histological diagnosis and to establish adequate therapy. Light microscopy showed marked tubulointerstitial inflammation with granulomatous changes, and electron microscopy revealed that numerous osmiophilic inclusions were present in podocytes, mesangial cells, and endothelial cells of the glomeruli and in epithelial cells of the tubules. The alpha-galactosidase activity of lymphocytes from the patient was measured, and the results of this assay indicated that the patient's lymphocytes had a low level of alpha-galactosidase activity. Therefore, the patient was diagnosed as having Fabry's disease with renal dysfunction. This study demonstrated that the onset age of renal insufficiency in Fabry's disease may be earlier than that described previously, and that when granulomatous interstitial nephritis is developed, renal function may deteriorate progressively.
Improved techniques for detecting in situ hybridization signals on fluorescent G-bands are described. Prior to hybridization of biotinylated DNA probes, chromosomes with replication G-bands were treated with formaldehyde and denatured with an alkaline solution. These steps preserve chromosome morphology well, and enable us to simultaneously demonstrate fluorescein hybridization signals and G-banded chromosomes stained with propidium iodide. This method is useful for precise chromosomal localization of DNA markers.
A 80-year-old woman with right ventricular wall perforation and extraction into the left thoracic cavity by a permanent endocardial pacemaker (PM) lead was presented. The patient underwent an insertion of a permanent endocardial lead into the apex of the right ventricle for the treatment of sick sinus syndrome. The right ventricular perforation of the PM lead was incidentally diagnosed by recognizing it into the left thoracic cavity three months after the operation. Another PM lead could be inserted without removal of the former one.
Cytidylate cyclase is a membrane-bound enzyme which catalyzes the biosynthesis of cytidine 3',5'-cyclic monophosphate (cCMP) from CTP. By using a sensitive and specific enzyme immunoassay method, we evaluated the participation of guanine nucleotide-binding protein (G-protein) in the regulation of cytidylate cyclase activity in rat brain and other tissues. AlF4-, an activator of G-proteins, effectively elevated the cyclase activity. The stimulation by GTP gamma S, a nonhydrolyzable GTP analogue, was also observed in time- and concentration-dependent manner during the preincubation and this effect was competitively inhibited by the addition of GDP beta S. However, islet-activating protein and cholera toxin which affected adenylate cyclase activity had no effect on cytidylate cyclase activity. These results indicate that cytidylate cyclase is associated with a certain G-protein and its activity is regulated by the mode different from that of adenylate cyclase.
The expression of myelin-specific protein genes, i.e. myelin proteolipid (PLP), basic (BP), and myelin associated glycoproteins (MAG) was studied in normal and severely undernourished 20-day-old rats. The undernutrition paradigm resulted in reductions of approximately 50, 25 and 65% in body weight, brain weight and brain myelin yield, respectively. The amount of total brain RNA was not significantly altered, although the amount of cyclophilin (CYC) mRNA was increased. In contrast, the steady-state levels of myelin specific mRNAs were significantly decreased by approximately 40, 20 and 40% for PLP, BP and MAG, respectively. In addition, polyadenylation of the PLP transcript was altered, producing an abnormal ratio of the 1.6 kb to the 3.2 kb PLP mRNAs. The results indicate that down-regulation of myelin-specific gene expression is involved in the mechanisms of hypomyelination in hunger disease, although the individual genes are differently altered. Furthermore, undernutrition may have additional effects on the posttranscriptional processing of the transcripts as indicated by the abnormal size distribution of PLP messages.
A model culture system of C6 rat glioma cells was used to test the involvement of cAMP in the regulation of the myelin PLP and MAG genes. The treatment of cells with isoproterenol (10(-5) to 10(-8) M) upregulated the expression of the PLP and MAG genes in a concentration-dependent manner. The mRNA for PLP reached a maximum (sevenfold higher than in control cells) after about 12-24 hr, then declined to approximately fourfold over the control level. The response of MAG gene was delayed by at least 36 hr, and the level of MAG mRNA reached a maximum of approximately 48-fold over the control level on the fourth day in culture. The co-administration of propranolol blocked the effect of isoproterenol, whereas 10(-5) M forskolin simulated the effect of isoproterenol, indicating a role of cAMP in the signal transduction cascades leading to upregulation of the myelin genes. However, the dissimilarity in the timing and the extent of upregulation of the PLP and MAG genes by cAMP-stimulating agents indicate the existence of different intracellular mechanisms for the activation of these two genes. Cycloheximide blocked the stimulatory effect of isoproterenol on both the PLP and MAG genes, indicating that the effect of cAMP on the myelin genes is mediated by protein product(s) of other cAMP-response gene(s).
The effect of retinoic acid (RA) on the expression of myelin-specific genes, i.e., proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) in rat glioma C6 cells, was analyzed by Northern blot hybridization. RA-treatment increased the steady-state level of the PLP-specific messages within one day after RA administration and the upregulation reached a maximum on the third day. Concomitantly, the expression of MAG-specific messages in the RA-treated C6 cells dropped below the detectability limit. The expression of the PLP gene was directly related to the RA concentration increasing to approximately 44-fold over the control (untreated cells) level at 10(-6) M RA. The stimulatory effect was vitiated by cycloheximide indicating the involvement of intermediate genes in the PLP gene activation. The total cellular RNA content and the level of cyclophilin mRNA was not changed by the RA-treatment. The present data indicate that RA can be a potent modulator of the myelin-specific gene expression. Furthermore, the reciprocal response of PLP versus MAG genes to RA demonstrates that these two genes utilize different regulatory mechanisms.
The effect of factors released from N2A neuroblastoma cells on the expression of myelin protein genes in glioma C6 cells, i.e., proteolipid protein (PLP) and myelin-associated glycoprotein (MAG), was studied. Both cells lines were propagated in serum-free DMEM-F10 (1:1) medium. The addition of 50% N2A conditioned medium (N2ACM) stimulated the proliferation of C6 cells by approximately 4.5 fold as compared to control cells. The N2ACM-treated cells formed aggregates indicating increased cell-cell affinity. The exposure of C6 cells to N2ACM transiently stimulated the expression of both the MAG-specific and the PLP-specific messages up to eight and four fold over the control values, respectively. The maximal upregulation of the PLP gene occurred two days after N2ACM administration and preceded that of the MAG gene by two days. The effect of N2ACM was dose-dependent in the range of 12.5 to 50%. The secretion of N2A paracrine factors that stimulated the myelin gene expression was also time-dependent. The optimal conditioning time for the release of the PLP gene-stimulating activity was one day, while the maximal MAG gene-stimulating activity was found in the medium conditioned for 3 days. This cellular system may provide a convenient model for studies on trophic neuronal-glial interaction. Furthermore, the results indicate a difference in the regulatory mechanisms between the PLP and the MAG genes.
The effect of age on resting-state cerebral blood flow (CBF) was studied in 40 medicated patients with chronic schizophrenia aged 20 to 57 and 32 age- and sex-matched normal controls, using the regional CBF with the xenon-133 inhalation technique. Global CBF (average of 16 cerebral regions) and the left prefrontal flow ratio (left prefrontal/global CBF) were significantly lower in schizophrenics aged 20-29 than in age-matched controls. Both global CBF and the left prefrontal flow ratio correlated with age in controls, but neither of such correlations was found in schizophrenics. Therefore, the CBF deficits in chronic schizophrenia appear to be unaffected by the aging process.
The prevalence of silent myocardial ischemia was retrospectively assessed in a group of 100 consecutive patients with angiographically proved coronary artery disease, and diagnostic ECG, by symptom-limited exercise thallium-201 scintigraphy. Twenty-four patients had no evidence of ischemia despite adequate exercise level. So among 76 patients with exercise induced ischemia, only 33 patients (43%) stopped exercise due to anginal pain (symptomatic ischemia: Group 3). And 43 patients with asymptomatic ischemia composed of 23 patients (30%) with ECG change (Group 2B) and 20 patients (26%) without ECG change (Group 2A). Patients background including the history of old myocardial infarction and diabetes mellitus, were similar among Group 2A, 2B, and Group 3. And our major observation was that the extent and severity of quantified SPECT perfusion defects was nearly identical between 3 groups Thus in this study group, there was a rather high prevalence rate of silent ischemia (57%) by exercise thallium-201 criteria. Patients with silent ischemia, associated with positive and negative exercise ECG findings, and those with exercise angina had similar background and comparable amount of jeopardized myocardium.
Thirty-eight cataract eyes and 15 artificial aphakic or pseudophakic eyes were enrolled in this study to determine levels of human epidermal growth factor (hEGF) and basic fibroblast growth factor (bFGF) in human aqueous, using a radioimmunoassay. Neither hEGF nor bFGF were detected in either congenital cataract eyes or senile cataract eyes without any complication. In cases of senile cataract complicated with glaucoma and traumatic cataract, bFGF range from 0.4 to 0.8 ng/ml whereas hEGF was not detected. In cases of senile cataract with myocardial or brain infarction and anterior subcapsular cataract, bFGF was detected ranging from 0.4 to 1.0 ng/ml and in some of the cases hEGF was detected at a level of 1.0 ng/ml. hEGF was detected at 1.0 ng/ml in some cases of secondary cataract after uveitis, cataract complicated with retinal detachment, cataract after scleral buckling or vitrectomy, and aphakic or pseudophakic eyes after extracapsular cataract extraction or phacoemulsification. These results showed that hEGF and bFGF exist at a level of about 1 ng/ml in human aqueous in some pathological states and it seems possible that proliferation of lens epithelial cells is promoted by the growth factors, with the result that after cataract, anterior capsular opacities and shrinkage become severe.
The effects of culture conditions on the expression of myelin-specific genes, i.e. proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) in rat glioma C6 cells was studied. Early passage (40-46) cells had higher steady-state level of PLP- and MAG-specific mRNA than late (100) passage cells when grown in defined (serum-free) medium. The PLP gene expression was increased whereas the MAG gene expression was reduced in the presence of 10% fetal calf serum in either passage. The level of both PLP- and MAG-specific messages was also directly related to the cell density indicating cell contact-induced stimulation of the gene expression. Furthermore, the cells apparently secrete factors into the medium, which upregulate the gene expression in autocrine fashion. The results also indicate a dissimilarity of regulatory mechanisms involved in the expression of the PLP and MAG genes.
Rat glioma C6 cells were stably transfected with a pSV3-neo plasmid containing SV40 T antigen gene, and geniticin-resistant transfectants (designated C6T cells) were cloned. The C6T cells grew as well-defined foci of cells showing squamous or irregular morphology. The doubling time for transfected cells was reduced by approximately 40% as compared to control C6 cells. The transfection with T-antigen also affected the expression of genes coding for structural myelin proteins and for myelin-associated enzymes. The steady-state level of proteolipid protein (PLP)-specific mRNA in C6T cells was 44% lower than in parental C6 cells. On the other hand, the transfection upregulated the expression of myelin-associated glycoprotein (MAG) by 153%. The activity of 2':3' cyclic AMP phosphodiesterase (CNP) was increased by approximately 80% in the C6T cells as compared to untransfected, control cells. The activity of calcium-activated neutral proteinase (CANP) was also significantly elevated in the transfectants by approximately 50% and 220% for millimolar and micromolar form respectively. The results indicate that T antigen affects the expression of myelin genes, although, individual genes appear to be differently regulated implying the existence of several independent regulatory mechanisms.
A controlled randomized study was carried out to evaluate the effects of chemotherapy in patients with brain metastases from lung carcinoma. One hundred patients were randomly divided into three groups at the time of diagnosis or after surgery for metastases. Group A received radiotherapy alone; Group B received radiotherapy and chloroethylnitrosoureas (methyl-CCNU, 100-120 mg/m2, or ACNU 80-100 mg/m2, every 6-8 weeks), and Group C received radiotherapy and a combination of chloroethylnitrosoureas and tegafur (300 mg/m2, daily). Of the 100 patients, 88 could be evaluated. The reduction rates of the tumors of the patients in whom tumor was not surgically removed or not totally removed were compared. Complete resolution of the tumor was noted in 29, 69, and 63% of the patients in Groups A, B, and C, respectively. Tumor regression of greater than or equal to 50% was seen in 36, 69, and 74% of the patients in Groups A, B, and C, respectively. The difference in the response rates of Groups A and C was statistically significant (P less than 0.05). Median survival after the start of treatment for brain metastasis was 27, 30.5, and 29 weeks in Groups A, B and C, respectively. There was 1 long-term survivor (more than 5 years) in Group A, 3 in Group B, and 1 in Group C. The main cause of death was deterioration attributable to the primary lesion or systemic metastasis, and no statistical difference was noted in survival time among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)
The purpose of this paper is to investigate memory processes in an epileptic with amnesia. Selective impairment of memory in organic amnesia has been reported in some clinical observations. They also demonstrated that organic amnesia can retain some aspects of learning experience, despite their inability to recollect them. We investigated an effect of priming task repetition on memory processes in a female with organic amnesia aged 28 (probable encephalitic patient) and eight control college students aged 20-26. In this paper, her memory processes were analyzed, using the same picture priming task, carried twelve times during the period of seven months. We used semantic priming paradigm. Three types of prime-target pair were used: identical, semantically related and unrelated. After a prime picture, a target picture appeared on the CRT display. She was asked to name each target as rapidly and accurately as possible. We analysed reaction time (RT) in naming the picture targets, error rate, and verbal reports of the priming task in the pre- and post-examination interview. In the first examination, priming effect was observed in her RT as in the controls'. This suggests that she retained some amount of semantic memory, and the structure of her semantic memory closely resembled that in the controls. Naming RT reduced and error rate decreased with repetition of the examination. This suggests that she acquired picture naming skill during early few examinations. However it was difficult for her to recognize and recollect the picture stimuli in this period. Further, she did not show any episodic memory of the examinations. There was dissociation between improved RT performance and poor verbal reports during early few examinations. When the same priming task was repeated in early few examinations, the priming effect became weaker in her RT. In the controls, on the contrary, the priming effect remained during the whole task repetition. Semantic strategy was apparently used in the controls, but not in the amnesic patient. She apparently used strategy of non-semantic association between the prime and target. In the last few examinations, her naming RT delayed and the priming effect was observed again as in the first examination. She seemed to use semantic strategy. In addition to this priming effect, she re-collected a few pictures and showed some episodic memory of the examination.(ABSTRACT TRUNCATED AT 400 WORDS)
Unactivated human blood monocytes and monocytic THP-1 cells were found to respond to some leukemia cells by tumor necrosis factor (TNF) production. The TNF production by THP-1 cells in response to K562 cells was preceded by a rapid rise in [Ca2+]i, initiated within 1 h and terminated within 4 h as a refractory state took over. Neither the amount nor the duration of TNF production was enhanced by gamma-interferon. The P32/ISH cells did not induce a significant [Ca2+]i change of TNF production, while MOLT-4 cells failed to induce TNF despite their capacity to mobilize Ca2+ in THP-1 cells. The failure of P32/ISH or MOLT-4 to induce TNF was attributed primarily to a lack of stimulatory membrane molecules rather than to suppression by an inhibitory component, since liposomes carrying membrane components of K562 and MOLT-4 or P32/ISH in varying proportions elicited TNF production that precisely reflected the K562 proportion. The ability of K562 to induce TNF was selectively impaired by trypsin, whereas the ability to mobilize [Ca2+]i was more sensitive to glutaraldehyde, although once the latter activity was extinguished, the K562 cell could no longer induce TNF. These results suggest that some leukemia cells are equipped with two or more signaling membrane moieties which together stimulate monocytes for transient tumoricidal expression in the preimmune stage.