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T Kanda

Publications and source records attributed to T Kanda.

At least 379 records · Page 21Linked to original sources
PubMed1994

Ubiquitin and ubiquitin-protein conjugates in PC12h cells: changes during neuronal differentiation.

Ubiquitin and ubiquitin-protein conjugates in PC12h cells were detected with in vitro [125I]ubiquitination, and quantified by immunoblotting. These levels were altered by nerve growth factor (NGF), which promotes neuronal differentiation. (i) Levels of high molecular weight (HMW) ubiquitin-protein conjugates ranging from 40 to 1,000 kDa were increased by 2 days of NGF treatment, and remained high up to 10 days of NGF treatment. (ii) Ubiquitin and a 23-kDa conjugate tended to be decreased from days 2 to 10 of NGF treatment. 10-Day culture with 10 nM staurosporine, n protein kinase inhibitor, that blocks NGF-induced neurite outgrowth suppressed the NGF-induced increases in levels of HMW conjugates. Cyclic AMP and forskolin, both of which promote neurite outgrowth, mimicked the NGF-induced changes in ubiquitin and HMW conjugates, but phorbol ester and epidermal growth factor had little effect. These findings suggest that changes in ubiquitin-protein conjugates are closely coupled with neuronal differentiation.

Alkaloids↗
PubMed1994

The diagnostic value and limitation of magnetic resonance imaging on chondral lesions in the knee joint.

Chondral lesions of the knee joint, which have been detected via arthrotomy or arthroscopy, were examined prospectively and retrospectively through a review of previously obtained magnetic resonance images (MRIs). The study group was composed of 34 men and 29 women whose average age was 24.6 years. Of these 63 patients, there were 72 articular cartilage lesions in 65 knees. On retrospective analysis, the sensitivity of MRI, which was defined as a true positive reading for softening, fragmentation, erosion, and/or a full-thickness loss of cartilage, was 14.3%, 57.3%, 75.0%, and 100%, respectively. Although the sensitivity to early changes of chondral lesions was low, indicating the limitation of MRI at the present stage, it has been demonstrated that MRI can delineate intracartilaginous changes associated with softening and thickening of cartilage that cannot be detected even with arthroscopy. Therefore, it may be worthwhile to perform an MRI as well as arthroscopy to clarify the pathogenesis of internal derangement of the knee.

Adult↗
PubMed1994

Glycosphingolipid antigens in cultured bovine brain microvascular endothelial cells: sulfoglucuronosyl paragloboside as a target of monoclonal IgM in demyelinative neuropathy [corrected].

Since a number of anti-glycosphingolipid (GSL) antibody activities have been demonstrated in patients with various neurological disorders, the presence of common antigens between brain microvascular endothelial cells (BMECs) and the nervous tissues presents a potential mechanism for the penetration of macromolecules from the circulation to the nervous system parenchyma. We first investigated GSL composition of cultured bovine BMECs. Bovine BMECs express GM3(NeuAc) and GM3(NeuGc) as the major gangliosides, and GM1, GD1a, GD1b, GT1b, as well as sialyl paragloboside and sialyl lactosaminylparagloboside as the minor species. Sulfoglucuronosyl paragloboside was also found to be a component of the BMEC acidic GSL fraction, but its concentration was lower in older cultures. On the other hand, the amounts of neutral GSLs were extremely low, consisting primarily of glucosylceramide. In addition, we analyzed the effect of anti-SGPG IgM antibody obtained from a patient of demyelinative polyneuropathy with macroglobulinemia against cultured BMECs. Permeability studies utilizing cocultured BMEC monolayers and rat astrocytes revealed that the antibody facilitated the leakage of [carboxy-14C]-inulin and 125I-labeled human IgM through BMEC monolayers. A direct cytotoxicity of this antibody against BMECs was also shown by a leakage study using [51Cr]-incorporated BMECs. This cytotoxicity depended on the concentration of the IgM antibody, and was almost completely blocked by preincubation with the pure antigen, sulfoglucuronosyl paragloboside. Our present study strongly supports the concept that immunological insults against BMECs induce the destruction or malfunction of the blood-nerve barrier, resulting in the penetration of the immunoglobulin molecule to attach peripheral nerve parenchyma.

Animals↗
PubMed1994

Trombiculid fauna and seasonal abundance of Leptotrombidium scutellare (Acari: Trombiculidae) in an endemic area of scrub typhus (Tsutsugamushi disease) in Yamakita Town, Kanagawa Prefecture, Japan.

Using the Tullgren funnel method, we surveyed for trombiculid larvae around dwellings and in mandarin orange groves on the slopes of Sengenyama and Maruyama, Yamakita Town, Kanagawa Prefecture, Japan, during the period between 8 October 1992 and 8 January 1993. In total, 6,690 trombiculid larvae, consisting of 6,669 Leptotrombidium scutellare (Nagayo, Mitamura, Tamiya & Tenjin), 13 L. fuji Kuwata, Berge & Philip, two L. himizu (Sasa, Kumada, Hayashi, Enomoto, Fukuzumi & Obata), two Neotrombicula japonica (Tanaka, Kaiwa, Teramura & Kagaya), one Gahrliepia saduski Womersley, and three Walchia ogatai Sasa & Teramura, were taken from 240 soil samples (40 samples, six times at intervals of 2-4 wk). From the above species composition, L. scutellare is suspected to be the sole vector of scrub typhus in the survey area, where the disease is known to be caused by two serotypic strains of Rickettsia tsutsugamushi Ogata, Kawasaki and Kuroki. L. scutellare larvae rapidly increased in number in late October to form an acuminate peak of abundance in early November, followed by a gradual wane.

Agriculture↗
PubMed1994

Myocardial beta-receptor and cardiac angiotensin alterations during the acute and chronic phases of viral myocarditis.

Recovery from viral myocarditis is usually excellent and complete although it occasionally results in sudden death during its acute stage. While neurohormonal mechanisms play an important role in the adaptation to heart diseases, little is known about the alteration of the neurohormonal system in viral myocarditis. Therefore, we examined the myocardial beta-adrenergic receptor and cardiac angiotensin I and II concentrations in a murine model of viral myocarditis induced by an encephalomyocarditis virus. The down-regulation of the beta 1-adrenergic receptor subtype was observed on day 10. The heart weight, heart weight/body weight ratio and myocardial necrosis were significantly increased at this stage. On day 30, the beta 2-adrenergic receptor subtype was up-regulated without up-regulation of the total beta-adrenergic receptor. Both angiotensin I and II concentrations were significantly increased with myocardial hypertrophy in the left ventricle on day 30. The up-regulation of the total beta-adrenergic receptor and beta 2-subtype was observed on day 120, but neither the angiotensin I nor II concentration was increased. Therefore, the up-regulation of the beta 2-adrenergic receptor density and the temporal increase of the angiotensin I and II concentrations in the murine ventricle during viral myocarditis may play an important role in the pathophysiology of post-viral myocarditis.

Angiotensin I↗
PubMed1994

Hydrolysis of cotton cellulose by Exo- and endo-type cellulases from Irpex lacteus: differential scanning calorimetric study.

The mode of hydrolysis of cotton cellulose by two highly purified exo- and endo-type cellulases from Irpex lacteus was investigated by differential scanning calorimetry, to measure changes in the size of the amorphous region in cotton fibers with the enzymatic reaction. The cellulases induced entirely different changes in the size of the amorphous region, particularly at earlier stages of reaction. Exo-type cellulase gradually reduced the amorphous region with release of cellobiose from the initial stage of hydrolysis, but began to increase the amorphous region at more advanced stages of hydrolysis. By contrast, endo-type cellulase caused no liberation of reducing sugar at the initial stage of hydrolysis but caused a sharp increase in the amorphous region, and it thereafter caused a rapid decrease of the amorphous region, accompanied with the production of various kinds of cellooligosaccharides. The rate of size reduction of the amorphous region caused by endo-type cellulase was much higher than that by exo-type cellulase. Convergence of the decrease in the size of amorphous region during hydrolysis by endo-type cellulase is followed by the increase in this region being influenced by further hydrolysis of remained crystalline region. Substantial changes in the morphology of cotton occurred with the two cellulases after the hydrolysis stages at which the size of the amorphous region was minimum.

Calorimetry, Differential Scanning↗
PubMed1994

[A case of pediatric Chlamydia pneumoniae infection and properties of the isolate].

Chlamydia pneumoniae was isolated from the throat of a 2-year-old girl with upper respiratory illness. The isolate, Shizuoka-37, was stained with C. pneumoniae specific monoclonal antibody (RR402), as well as the genus specific antibody (Cultureset), but not with C. trachomatis specific monoclonal antibody (Micro-Trak). C. pneumoniae genome was amplified by polymerase chain reaction in the isolate. Elementary bodies (EB) of the isolate was round shaped by electron micrograph.

Child, Preschool↗
PubMed1994

Stimulation of polyomavirus DNA replication by wild-type p53 through the DNA-binding site.

The tumor suppressor p53 possesses characteristics of a transcription factor; it binds to specific DNA sequences and activates transcription from various promoters. Here we found that murine wild-type p53 stimulated not only transcription but also polyomavirus (Py) DNA replication in a sequence-dependent manner. Oncogenic mutant p53, lacking the DNA-binding activity, showed no stimulation of Py DNA replication. Deletion of the N-terminal acidic transactivation domain of wild-type p53, which completely eliminated the ability to stimulate transcription, only impaired the function to stimulate Py DNA replication. The replication-stimulating activity of wild-type p53 was impaired by the deletion of the C-terminal oligomerization domain as well, without affecting the ability to stimulate transcription. The region responsible for the sequence-specific DNA-binding activity mapped to the central portion of the p53 molecule has a minimal activity. The results indicate that both the N-terminal and the C-terminal regions significantly contribute to the p53-mediated stimulation of Py DNA replication.

Amino Acid Sequence↗
PubMed1994

A transient increase of phenylalanine ammonia-lyase transcript in kinetin-treated tobacco callus.

In tobacco cell culture (Nicotiana tabacum L. "Bright Yellow" T-13), phenylalanine ammonia-lyase (PAL) activity was induced in response to an exogenously added kinetin. RNA blot hybridization analysis showed that a single species of PAL transcript 2.9-kb in size was detected using the PAL cDNA cloned from kinetin-treated cells. The cellular content of this transcript increased transiently (2.5-fold) 4 h after the addition of kinetin followed by an increase in PAL enzyme activity at 16 h.

Adenine↗
PubMed1994

An interleukin-6 secreting myxoma in a hypertrophic left ventricle.

We describe a patient who had both a left ventricular myxoma and left ventricular hypertrophy; the myxoma was subsequently excised and revealed to produce interleukin-6. The combination of left ventricular myxoma and ventricular hypertrophy is uncommon. Interleukin-6 secreted from the myxoma may be an important factor in the pathogenesis of ventricular hypertrophy in this patient.

Aged↗
PubMed1994

Holter monitoring as a noninvasive indicator of cardiac involvement in sarcoidosis.

We investigated the usefulness of 24-h Holter monitoring for identification of myocardial involvement in 38 patients with sarcoidosis, including 12 patients with cardiac sarcoidosis, and 58 healthy controls. Ventricular ectopic beats (VEB) > or = 100 beats per day were detected in 8 (67 percent) of 12 patients with cardiac sarcoidosis, in 2 (8 percent) of 26 patients without cardiac sarcoidosis, and in 3 (5 percent) of 58 healthy controls. Holter monitoring was associated with a sensitivity of 67 percent and a specificity of 62 percent for cardiac sarcoidosis in the overall study population. In patients with sarcoidosis, specificity was 80 percent. Lown's grade 4 A and 4 B VEBs were detected in 8 (67 percent) of 12 patients with cardiac sarcoidosis, in 2 (8 percent) of 26 patients with sarcoidosis without cardiac involvement, and in 2 (3 percent) of 58 controls. Holter monitoring was associated with a sensitivity of 67 percent and a specificity of 80 percent for identification of cardiac involvement in patients with systemic sarcoidosis. Our findings suggest that 24-h Holter monitoring provides a convenient and inexpensive means of noninvasive screening for cardiac involvement in generalized sarcoidosis, even in patients and outpatients who are without symptoms.

Cardiac Complexes, Premature↗
PubMed1994

[Glucose intolerance during interferon therapy in patients with chronic hepatitis type C].

A new side effect of interferon (IFN) therapy, glucose intolerance was investigated using insulin-clamp study. In 75 g oral glucose tolerance tests before and after the IFN therapy showed no significant difference, whereas clamp study showed a significant decrease of glucose disposal. Our data suggested that insulin resistance was the main reason for glucose intolerance observed during INF therapy in the patients with chronic active hepatitis C. Early detection and strict control of glucose intolerance could avoid the progress of glucose intolerance.

Chronic Disease↗
PubMed1994

Induction of asymptomatic HBeAG carrier state in a patient with Down's syndrome following human bite.

A 56-year-old Japanese male patient with Down's syndrome was bitten by a hepatitis B envelope antigen (HBeAg) carrier and become an asymptomatic HBeAg carrier without seroconversion. His mitogen response of T cells was poor compared with that of healthy controls. An impaired T cell response to hepatitis B virus infection may be responsible for the HBeAg carrier with Down's syndrome.

Bites and Stings↗
PubMed1994

[A study of children with cerebral palsy who were born between 1977 and 1985 in Kyoto City; a report from an institution for handicapped children].

First, we longitudinally analyzed 177 cerebral-palsied children (CP) who were born in Kyoto City between 1977 and 1985. They were all visited St. Joseph Hospital for Crippled Children in Kyoto during the period 1977 to 1991 in order to investigate the relationship between the prognosis of perinatal care and the changing panorama of CP in Kyoto. The average occurrence rate of CP per 1,000 live birth during the 9 years in Kyoto was 1.12. 177 CP were divided into 3 groups according to their birth years: 1977-1979 (47 CP); 1980-1982 (62 CP); and 1983-1985 (68 CP). Then we compared the distribution of birthweights and gestational periods among the 3 groups. We found a significant increasing trend in the percentage of CP in babies with birthweight less than 2,000 g. Second, we examined 162 CP; 15 born outside of Kyoto were excluded because of extraneous influences of perinatal care. 162 were divided into 3 groups according to their birth years: 1977-1979 (44); 1980-1982 (56); and 1983-1985 (62). We also compared the risk factors and prognosis according to the birthweights and gestational ages among the 3 groups. This study revealed a decreasing trend in the frequency of convulsions of full term CP, dyspnea and oxygen administration of premature CP in the neonatal period. At the same time, the motor development of CP without mental retardation had improved significantly in the later period. However, in the last 3 years the distribution of the severity of motor disturbance at 4 years of age among CP with birthweight of 1,000-2,000 g was either mild or severe.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1994

[Visual hallucination in the hemianopic field caused by dural arteriovenous malformation].

We presented a 65-year-old man with the right occipital dural arteriovenous malformation (AVM) who first experienced photopsia in his left inferior quadrantanopic field and then developed formed hallucinations 8 days later. His visual hallucinations disappeared with saccadic eye movements. EEG showed no epileptic discharge. MRI revealed hyperintensity in the right medial occipital lobe on proton density image. 123I-IMP SPECT during the hallucinations revealed decrease of regional cerebral blood flow (r-CBF) not only in the right medial occipital lobe but also in the right lateral occipital and in the right medial temporal lobe. Both left inferior quadrantanopia and visual hallucinations disappeared following the treatment of the dural AVM by transarterial embolizations. Because the lesion on MRI improved after the treatment, we considered that the lesion was brain edema, not infarction. Additionally decreased r-CBF in the temporo-occipital lesion on SPECT improved after the treatment, we emphasized the role of the temporo-occipital lesion as the cause of visual hallucinations in the hemianopic field.

Aged↗