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Biomedical subjects

T Kondo

Publications and source records attributed to T Kondo.

At least 919 records · Page 51Linked to original sources
PubMed1994

[A long-term clinical effect of selegiline hydrochloride on Parkinson's disease].

A long-term follow-up evaluation on the clinical usefulness of selegiline hydrochloride (selegiline) was performed in 13 patients with Parkinson's disease. All patients, except one case, subjected to the study were symptomatically improved by combination therapy of selegiline with L-DOPA in the preceding short-term evaluation. One patient continued the therapy after an evaluation of no symptomatic improvement in the short-term study, because this patient strongly requested continuation of medication, expecting to stop the progression of the disease. The average daily dose of selegiline at the last evaluation was 6.9 +/- 2.5 mg. The average daily dose of L-DOPA at each evaluation point in the patients who continued the therapy for 12 months remained low compared to that prior to the therapy (before: 450 +/- 117 mg, at the 12th month: 389 +/- 89 mg). In the analysis of individual parkinsonian symptoms, the improvement in the mean score for most of the symptoms, especially the wearing-off phenomenon and frozen gait, persisted for the entire period of study. Global improvement rates (moderately improved) at the 6th and 12th month, and the last evaluation were 61.5%, 44.4% and 46.2%, respectively. Among 13 patients, therapy was discontinued only in one case due to hallucination. Although the global improvement rate declined in the course of the therapy, selegiline seems to be useful for improving L-DOPA responsive symptoms in long-term therapy for Parkinson's disease.

Aged↗
PubMed1994

[Experience with surgery for metachronous double cancer originated from thymus and lung].

A case with thymic cancer who developed pulmonary cancer ten years after the initial surgery was reported. A 50-year-old man was admitted to our hospital due to SVC syndrome. Chest X-ray examinations including venogram showed a mass lesion at the superior mediastinum. The patient underwent surgical removal and reconstruction of SVC, followed by radio-chemotherapy. The histologic diagnosis was thymic squamous cell carcinoma. He was admitted to our hospital again ten years after the initial surgery under the diagnosis of pneumonia. Bronchoscopic examination revealed nodular lesions at the right upper lobe bronchus and lower lobe bronchus, those lesions were diagnosed with squamous cell carcinomas cytologically. Right pneumonectomy was performed and the diagnosis was confirmed pathologically. Postoperative course was uneventful as of 10 months after the operation. It was concluded that this case showed metachronous double cancer of the thymus and the lung, as well as synchronous multiple bronchogenic carcinomas, which, to our knowledge, has never been reported yet.

Carcinoma, Squamous Cell↗
PubMed1994

[Detecting impaired glucose tolerance based on medical decision making].

Impaired glucose tolerance (IGT) is recognized as a preclinical state of diabetes mellitus (DM), and therefore its detection is important in terms of preventive medicine. It is, however, difficult to perform an oral glucose tolerance test (OGTT) during usual health examinations due to time constraints. This study aims to establish an appropriate procedure for detecting IGT without OGTT. Subjects were 422 males who had annual health examinations and who did not have DM. The measurement of serum fructosamine (FRA) and glycosylated hemoglobin (HbA1C), and a 75-gram oral glucose tolerance test were conducted simultaneously. IGT cases were determined as those subjects whose glucose value after two hours of oral glucose administration was 140 mg/dl or above. Ninety-four persons were classified as having IGT with this criterion. Receiver operating characteristics (ROC) analysis and logistic regression analysis were conducted to determine the most appropriate procedure for the detection of IGT. The following results were obtained: 1. ROC analysis indicated that suitable cut-off values for FPG, HbA1C, and FRA were 100 mg/dl, 5.3%, 240 mumol/l respectively. 2. The following logistic function showed suitable diagnostic capability among the several combinations of medical tests: Y = 1/(1 + e-R); R = 0.027 x age + 0.035 x (body index [%]) + 0.074 x FPG [mg/dl] + 0.198 x HbA1C [%] - 11.286. When IGT was defined as a level of logistic function equal to 0.2 or above, the logistic function showed a sensitivity value of 0.755 and specificity value of 0.753.

Adult↗
PubMed1994

[A case of bronchial neurinoma treated with bronchofiberscopic electrosurgery and right S6 sleeve segmentectomy].

A 30-year-old woman was admitted for cough and fever over a period of two months. Her chest X-ray film showed atelectasis of the right middle and lower lobes. Bronchofiberscopic examination revealed complete obstruction of the truncus intermedius by polypoid tumor. Its punched biopsy specimen was diagnosed as the benign tumor. Bronchofiberscopic resection was performed by high frequency snare, however the tumor remained at the membranous portion of the truncus intermedius and the right B6 orifice. Therefore, right S6 sleeve segmentectomy was carried out after two weeks. The pathological diagnosis of the exturpated tumor was neurinoma. There were no complications and she is well without any evidence of recurrence after surgery. Neurinoma of the tracheobronchial tree is extremely rare and only 84 cases have been reported.

Adult↗
PubMed1994

Toxicological analysis for drugs and poisons using the formalin-fixed organ tissues. 1. Methamphetamine.

Methamphetamine (MA) was analyzed using formalin-fixed organ tissues from experimental animals and an autopsied cadaver. The brain, lung, liver, kidney and skeletal muscles of rabbits that had been administered MA were collected, and then fixed with a non-buffered 10% formalin solution at room temperature (10-20 degrees C) for five different fixation periods (1, 3, 7, 14 and 28 days). After the Extrelut column extraction, MA was derivatized using anhydrous trifluoroacetic acid (TFA) and analyzed by GC-MS using a DB-17 column. MA-TFA in the eluates from the organ tissues after the formalin-fixation could be identified by GC-MS. Even one day after the formalin-fixation, concentrations of MA in the fixed organ tissues already significantly decreased to 1.3-3.1% when compared with those of MA in the non-fixed tissues, and to 0.04-0.4% in all of the fixed organ tissues at 28 days after the fixation. Moreover, MA in the organ eluates from the autopsied male cadaver after one-month formalin-fixation was qualitatively detected. These results obviously show the usefulness of MA detection using formalin-fixed organs in the practice of forensic medicine and police science.

Animals↗
PubMed1994

[A 75-year-old man with parkinsonism and delirium].

We report a 75-year-old man with a ten-year history of parkinsonism, who developed acute delirium. He was well until 65 years of age, when there was an onset of tremor in his left hand. He had been treated with levodopa and trihexyphenidyl with marked improvement. He was doing well until July of 1991 at his age of 75-year-old, when he noted backache; he was found to have a compression fracture of the third lumbar spine. He had to use a wheel-chair most of the time since then. In December 1991, he started to have visual hallucinations and difficulty in swallowing. On December 25 of that year, he developed fever and delirium, and was admitted to our hospital on December 30. On admission, general physical examination was unremarkable except for low grade fever (37.3 degrees C). Neurologic examination revealed an alert but chronically ill patient. Apparently he had visual hallucinations. He was disoriented to all spheres; he could respond only to simple questions. Apparently he was demented. Cranial nerves were intact except for mumbling speech disturbance and masked face. He was unable to stand or walk. He had flexion contracture in his both knee joints. He had paratonic rigidity in all his limbs and marked bradykinesia. Once in a while, myoclonic jerks were seen in both upper and lower extremities. Deep reflexes were diminished bilaterally, and the plantar reflex was not elicited on either side. On laboratory examination, BUN was increased to 72 mg/dl, creatinine to 3.0 mg/dl, and WBC 16,000/microliter. Cranial CT scans were unremarkable.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Genomic binding-site cloning reveals an estrogen-responsive gene that encodes a RING finger protein.

Estrogen receptor (ER)-binding fragments were isolated from human genomic DNA by using a recombinant ER protein. Using one of these fragments as a probe, we have identified an estrogen-responsive gene that encodes a putative zinc finger protein. It has a RING finger motif present in a family of apparent DNA-binding proteins and is designated estrogen-responsive finger protein (efp). efp cDNA contains a consensus estrogen-responsive element at the 3' untranslated region that can act as a downstream estrogen-dependent enhancer. Moreover, efp is regulated by estrogen as demonstrated at both the mRNA and the protein level in ER-positive cells derived from mammary gland. These data suggest that efp may represent an estrogen-responsive transcription factor that mediates phenotypic expression of the diverse estrogen action. Thus, the genomic binding-site cloning may be applicable for isolation of the target genes of other transcription factors.

Amino Acid Sequence↗
PubMed1993

Temperature-sensitive phenotype of a mutant Sendai virus strain is caused by its insufficient accumulation of the M protein.

We investigated the process interrupting the production of a temperature-sensitive mutant strain of Sendai virus, Cl.151, at the nonpermissive temperature (38 degrees C). The amount of virus M protein increased up to 6-fold when the cells persistently infected with Cl.151 strain at 38 degrees C are transferred to 32 degrees C, while the amount of nucleocapsid proteins did not alter. Cl.151 strain could restore virus production at 38 degrees C not only by the supplementation of M protein of wild type (Z) strain but also by the supplementation of M protein of Cl.151 strain. Neither the amount of M mRNA nor the rate of synthesis of M protein was altered by temperature in cells infected with the Cl.151 strain. However, we found that M protein of Cl.151 virus, which has 3-amino acid alterations from the wild type, was highly unstable at 38 degrees C when expressed under the control of an actin promoter. These results clearly show that Sendai virus M protein has a critical role in the production of virus particles without affecting virus gene expression.

Amino Acids↗
PubMed1993

gamma-Glutamylcysteine synthetase and active transport of glutathione S-conjugate are responsive to heat shock in K562 erythroid cells.

Effect of heat shock on a glutathione-synthesizing enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), and ATP-dependent outward transport of glutathione S-conjugate was characterized using K562 erythroid cells. When K562 cells grown at 37 degrees C were shifted to 42 degrees C for 2 h, an approximate 1.7-fold increase in the activity of gamma-GCS was observed. Treatment of K562 cells with erythropoietin (EP) for 12 h resulted in a decrease in the activity of gamma-GCS to 64% of the control. However, responsiveness of this enzyme activity in the cells treated with EP to heat shock was similar to that in untreated cells. Changes in the immunological activity of gamma-GCS were also observed in parallel with those in the enzymatic activity. On Northern blot analysis of total RNAs isolated from the cells with human cDNA for gamma-GCS, a substantial induction of mRNA level was found by heat shock and a reduction of EP. These changes were modest but correlated to the mRNA expression of a heat shock protein, HSP 70. Heat shock also had an effect of 1.8-fold stimulation on glutathione S-conjugate transport in K562 cells previously incubated with 1-chloro-2,4-dinitrobenzene. Treatment of the cells with EP resulted in a decrease in this transport by 62%. Similarly, the levels of glutathione S-conjugate-stimulated Mg(2+)-ATPase, which enzyme is thought to be involved in the transport of glutathione S-conjugate, were responsive to heat shock and EP. These results suggest that glutathione synthesis and transport process of glutathione metabolites are responsive to heat shock and play a role in the defense system against stresses. It is also suggested that the regulatory site of the expression of these enzymes by heat shock is independent of that by EP.

Biological Transport, Active↗
PubMed1993

[Visualization of coronary arteries with helical scanning CT: diastolic reconstruction].

The purpose of this study was the visualization of coronary arteries by the diastolic reconstruction method with helical scanning (HES) CT. We chose diastolic phase images from the image data acquired with the HES technique using a continuous nutate-rotate fast CT scanner, because few motion artifacts are induced by cardiac pulsation during the slow filling diastolic phase. We assessed coronary diseases using this method based on HES-CT, and evaluated its clinical effectiveness. We also studied the clinical value of multiplanar reconstruction and three-dimensional surface reconstruction. The subjects consisted of 31 patients with coronary disease, aged 41-77 years. When a diastolic reconstruction HES-CT was employed, the average rate of visualization of the coronary arteries was 72%. An examination can be completed during a 30-second single breath-hold, permitting the acquisition of coronary artery images with excellent continuity. Calcified coronary arteries can be identified.

Adult↗
PubMed1993

Transduction of mitogenic activity of platelet-derived growth factor (PDGF) AB by PDGF-beta receptor without participation of PDGF-alpha receptor in vascular smooth muscle cells.

In cultured rat vascular smooth muscle cells, platelet-derived growth factor (PDGF) beta receptor was expressed at a high level, whereas PDGF-alpha receptor was not detected. PDGF-BB showed a high binding activity at 4 degrees C in the cells and was not displaced by PDGF-AA or -AB. This result indicates that PDGF-AB as well as PDGF-AA does not bind to the cells lacking PDGF-alpha receptor at 4 degrees C. However, at 37 degrees C, PDGF-AB bound to the cells and induced the internalization of PDGF-beta receptor. DNA synthesis was also stimulated potentially by PDGF-AB as well as PDGF-BB in the cells, although PDGF-AA was completely inactive. At 37 degrees C, PDGF-AB caused tyrosine phosphorylation of a group of proteins including PDGF-beta receptor and phospholipase C-gamma 1, but at a slower rate than PDGF-BB. At 4 degrees C, PDGF-AB did not stimulate protein tyrosine phosphorylation, whereas PDGF-BB did. A chemical cross-linking experiment showed that PDGF-beta receptor was dimerized by PDGF-AB as well as PDGF-BB. These results indicate that PDGF-beta receptor binds PDGF-AB without participation of PDGF-alpha receptor at 37 degrees C (but not at 4 degrees C), and PDGF-AB as well as PDGF-BB acts as a potent mitogen in the vascular smooth muscle cells.

Animals↗
PubMed1993

Neurotransmitter release from lysophosphatidic acid stimulated PC12 cells: involvement of lysophosphatidic acid receptors.

The significance of phospholipase D in metabolic regulation is being recognized. The products of phospholipase D action are phosphatidic acid and lysophosphatidic acid (LPA). Whether these lipid products exert their effect through plasma membrane receptor-mediated mechanism is not yet clear. In the present study we have shown the presence of specific receptors for LPA in plasma membranes of PC12 pheochromocytoma cells. LPA evoked a transient rise in [Ca2+]i concomitant with formation of IP3. LPA also stimulated dopamine release from PC12 cells. These results indicate that LPA stimulates catecholamine release via specific LPA receptors presumably by activating the IP3 mediated Ca2+ release.

Animals↗
PubMed1993

Circadian rhythms in prokaryotes: luciferase as a reporter of circadian gene expression in cyanobacteria.

We have used a luciferase reporter gene and continuous automated monitoring of bioluminescence to demonstrate unequivocally that cyanobacteria exhibit circadian behaviors that are fundamentally the same as circadian rhythms of eukaryotes. We also show that these rhythms can be studied by molecular methods in Synechococcus sp. PCC7942, a strain for which genetic transformation is well established. A promoterless segment of the Vibrio harveyi luciferase structural genes (luxAB) was introduced downstream of the promoter for the Synechococcus psbAI gene, which encodes a photosystem II protein. This reporter construction was recombined into the Synechococcus chromosome, and bioluminescence was monitored under conditions of constant illumination following entrainment to light and dark cycles. The reporter strain, AMC149, expressed a rhythm of bioluminescence which satisfies the criteria of circadian rhythms: persistence in constant conditions, phase resetting by light/dark signals, and temperature compensation of the period. Rhythmic changes in levels of the native psbAI message following light/dark entrainment supported the reporter data. The behavior of this prokaryote disproves the dogma that circadian mechanisms must be based on eukaryotic cellular organization. Moreover, the cyanobacterial strain described here provides an efficient experimental system for molecular analysis of the circadian clock.

Circadian Rhythm↗
PubMed1993

Differing signal transductions elicited by three isoforms of platelet-derived growth factor in vascular smooth muscle cells.

The differing signal transductions elicited by three isoforms of platelet-derived growth factor (PDGF) were studied in cultured rat vascular smooth muscle cells (VSMC), which show different mitogenic responses to the three PDGF isoforms. PDGF-BB elicited a variety of cellular signals, including the phosphorylation on tyrosine of phospholipase C-gamma 1 (PLC-gamma 1) and the PDGF receptor, formation of inositol 1,4,5-trisphosphate and diacylglycerol, degradation of phosphoinositides (phosphatidylinositol, phosphatidylinositol 4-phosphate, and phosphatidylinositol 4,5-bisphosphate) and elevation of intracellular calcium ([Ca2+]i). However, PDGF-AB failed to show some of these signals, although it stimulated [3H]thymidine incorporation to almost the same extent as PDGF-BB. Importantly, phosphorylation on tyrosine of the PLC-gamma 1 was far less (< 6.25%) in the case of PDGF-AB than that of PDGF-BB when assessed by immunoblotting. On the other hand, calcium ion entry from the extracellular medium was comparable in PDGF-AB- and PDGF-BB- stimulated VSMC. PDGF-AA, which did not stimulate [3H]thymidine incorporation, failed to show any of these effects with the exception of diacylglycerol formation. These observations suggest that the three PDGF isoforms stimulate different signal transduction pathways and that calcium ion entry, but not tyrosine phosphorylation of PLC-gamma 1, is essential for PDGF-induced mitogenesis in VSMC.

Animals↗
PubMed1993

Novel secretory heparin-binding factors from human glioma cells (glia-activating factors) involved in glial cell growth. Purification and biological properties.

Growth factors for rat primary glial cells were identified in conditioned medium of a human glioma-derived cell line. The factors, designated glia-activating factors (GAFs), were purified to homogeneity by a combination of heparin affinity chromatography, gel filtration, and high performance liquid chromatography on a heparin affinity column and a C4 reversed-phase column. GAFs could be resolved into three peaks by C4 column chromatography. The M(r) values of these three proteins were estimated to be 30,000, 29,000, and 25,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. These M(r) values were in good agreement with the value of 26,000 +/- 3,000 estimated from the elution volume upon gel filtration chromatography under nondenaturing conditions. These data suggested that each of the GAFs consists of a single polypeptide chain and has no subunit structures. These three purified GAFs had almost the same growth-stimulating effect on glial cells in vitro, and the half-maximal dose was around 10(-11) M. Concanavalin A staining and glycopeptide N-glycosidase treatment of GAFs indicated that an asparagine-linked oligosaccharide chain(s) was attached to these three kinds of GAFs. Microsequencing of each GAF revealed a single amino-terminal sequence with no significant homology to any known protein, and the amino-terminal sequence of the 30-kDa GAF included that of the 29-kDa GAF. GAFs also stimulated the cell growth of oligodendrocyte type 2 astrocyte progenitor cells, BALB/c3T3 fibroblasts, and PC-12 cells but not that of human umbilical vein endothelial cells.

Amino Acid Sequence↗