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Biomedical subjects

M Shimizu

Publications and source records attributed to M Shimizu.

At least 901 records · Page 50Linked to original sources
PubMed1993

Pronounced ST-segment depression during paroxysmal supraventricular tachycardia.

To determine the clinical significance of ST-segment depression observed in paroxysmal supraventricular tachycardia (PSVT), we evaluated the 12-lead electrocardiogram (ECG) during spontaneous PSVT in 54 patients (27 men and 27 women: mean age +/- SD; 47 +/- 18 years), who came to our clinic for the treatment of PSVT. Coronary angiography was performed in 16 patients (16 to 74 years; mean = 50 +/- 18) and treadmill exercise testing was performed in 21 patients. A cardiac electrophysiological study was carried out in 24 patients. During PSVT, ST-segment score was calculated as the sum of the ST-segment depression in 12 leads. The correlations between the ST-segment score, PSVT rate and age of the patient were analyzed as follows: The most significant positive correlation was observed between the ST-segment score and the PSVT rate (r = 0.615, p < 0.000001). The next most significant correlation was found between the PSVT rate and the age of the patient (r = -0.500, p = 0.00011). A negative correlation was also observed between the ST-segment score and the age of the patient (r = -0.429, p = 0.0012). In 13 of 16 patients, coronary angiography did not reveal any significant (> or = 75% in area) stenosis. Exercise testing induced significant ST-segment depression in 3 patients, of whom two had significant coronary artery lesions. PSVT was due to atrioventricular reentry via an overt (n = 3) or concealed accessory pathway (n = 15), atrioventricular nodal reentry (n = 5) and sinus node reentry (n = 1). In conclusion, patients with a faster PSVT rate revealed more pronounced ST-segment depression than did those with a slower PSVT rate, possibly reflecting the modified repolarization process instead of coronary artery involvement.

Adult↗
PubMed1993

Reversible left ventricular diastolic dysfunction resulting from frequent supraventricular tachycardia.

In two patients with frequent supraventricular tachycardia, echocardiograms revealed remarkable left ventricular systolic and diastolic dysfunction, associated with an absence of left ventricular filling during the early diastolic phase. This dysfunction was detected during normal sinus rhythm as well as tachycardia. By treatment with propafenone, both patients showed dramatic and rapid improvement of symptoms and the left ventricular dysfunction. Left ventricular diastolic dysfunction as well as systolic dysfunction were detected in patients with supraventricular tachycardia, suggesting that frequent supraventricular tachycardia results in severe left ventricular diastolic dysfunction which is reversible after control of the tachycardia.

Aged↗
PubMed1993

Apolipoprotein E polymorphism is associated with plasma cholesterol response in a 7-day hospitalization study for metabolic and dietary control in NIDDM.

OBJECTIVE: To investigate the effects of apolipoprotein E phenotype, which is an important genetic factor determining plasma cholesterol level, on plasma lipoprotein metabolism during a 7-day diet therapy of diabetes. RESEARCH DESIGN AND METHODS: Diet therapy was performed in 242 subjects with NIDDM. Plasma lipid levels and apolipoprotein A-I, B, and E levels on hospital days 2 and 9 were compared in three phenotype groups, epsilon 2 (E2/2, and E2/3), epsilon 3 (E3/3), and epsilon 4 (E3/4 and E4/4). RESULTS: No differences were observed in fasting blood glucose level, body mass index, age, duration of NIDDM, or medication among the three phenotype groups. Before starting the treatment, total plasma cholesterol did not vary by apolipoprotein E phenotype, although the mean plasma low-density lipoprotein cholesterol level in epsilon 4 patients was higher than in either epsilon 3 or epsilon 2 patients (epsilon 4, 145 +/- 42; epsilon 3, 131 +/- 34; epsilon 2, 128 +/- 36 mg/dl; P < 0.05). Changes in fasting blood glucose/body mass index after the 7-day treatment were not different among the apolipoprotein E phenotype groups, whereas the decrease in plasma cholesterol level after the treatment was significantly greater in epsilon 2 patients than in either epsilon 3 or epsilon 4 patients (epsilon 2, 10.3 +/- 14.2; epsilon 3, 6.1 +/- 11.0; epsilon 4, 3.8 +/- 9.6%; P < 0.05). CONCLUSIONS: Total plasma cholesterol response to in-hospital diet therapy varies by apolipoprotein E phenotypes, with subjects with apolipoprotein E2 showing the greatest response, whereas those with apolipoprotein E4 show the least. We suggest that subjects with apolipoprotein E4 should be controlled more strictly than other subjects from a viewpoint of reducing plasma cholesterol levels.

Alleles↗
PubMed1993

Discrimination among E. coli tRNAs with a long variable arm.

In E. coli, tRNA(Ser), tRNA(Leu) and tRNA(Tyr) have a long variable arm composed of more than ten nucleotides (class II tRNAs). In order to study how leucyl- and seryl-tRNA synthetase discriminate their cognate tRNA isoacceptors from the other class II tRNAs, kinetic parameters of various mutated class II tRNA transcripts with leucyl- and seryl-tRNA synthetase were determined. Leucyl-tRNA synthetase recognizes A73 and A14 or its vicinity. Seryl-tRNA synthetase recognizes the long variable arm base-nonspecifically. C2-G71 in the acceptor stem functions as a negative identity element against seryl-tRNA synthetase. Difference in the tertiary structure among class II tRNA molecules plays a crucial role in discrimination by these two synthetases.

Acylation↗
PubMed1993

Cytokeratin immunohistochemical study of epithelial cysts in the central nervous system: with special reference to origins of colloid cyst of the third ventricle and Rathke's cleft cyst in the sella.

A variety of epithelial cysts in the central nervous system were examined immunohistochemically for expression of cytokeratins. Colloid cysts, Rathke's cleft cysts and epithelial cysts in the spinal canal expressed complex type cytokeratins, while enterogenous cysts and neuroectodermal cysts showed only simple type cytokeratins. Colloid cysts showed a pattern of cytokeratins similar to that of upper respiratory tract which is endodermal in origin. In contrast, Rathke's cleft cysts showed a pattern of cytokeratins similar to that of the adenohypophysis and salivary gland which are ectodermal in origin. The CK immunohistochemical studies are discussed with regards to diagnostic significance and origins of their cysts.

Adult↗
PubMed1993

Immunohistochemical demonstration of ethanol-inducible P450 2E1 in rat brain.

The microsomal ethanol-oxidizing system (MEOS) is a P450-dependent pathway for ethanol oxidation in hepatic microsomes. The bulk of MEOS activity is catalyzed by P450 2E1 (an ethanol-inducible isozyme of P450) in animal livers treated with ethanol. Rat brains also metabolize certain drugs, and it is theorized that a mechanism for drug metabolism exists within the brain which acts on P450. We compared immunohistochemical localization of P450 2E1 between ethanol-treated rats and pair-fed control rats. In control rats, immunoreactive P450 2E1 was detected in minute amounts in both basal ganglia and cerebellar cortices. After ethanol treatment, the content of P450 2E1 increased in the basal ganglia, and the enzyme was also induced in the cerebellar cortices, substantia nigra and hippocampus. We speculate that the rat brain metabolizes ethanol by P450 2E1.

Alcoholism↗
PubMed1993

Effect of age on the development or progression of albuminuria in non-insulin-dependent diabetes mellitus (NIDDM) without hypertension.

To study the relationship between aging and development of diabetic nephropathy, we studied the time until the development of microalbuminuria in old onset (> 50 years old, n = 21) and young onset (< 40 years old, n = 26), normotensive NIDDM patients. Microalbuminuria which is associated with the early stage of diabetic nephropathy was defined as urinary albumin index (UAI; mg/g.creatinine) of more than 10mg/g.creatinine, using timed overnight urine. In these two groups, there were no significant differences in duration of diabetes, observation periods, glycemic control, systolic diastolic blood pressure, body mass index and creatinine clearance at the time of the last observation. Mean UAI +/- standard deviation of the two groups were 37.5 +/- 78.2 mg/g.cr and 93.0 +/- 127.2 mg/g.cr in the young onset group and the old onset group, and prevalences of microalbuminuria were 38% and 76% in the young onset and old onset group, respectively. Thus, UAI and prevalence of microalbuminuria in the old onset group are significantly higher than those of the young onset group (P < 0.05). These results suggest that aging, in itself, is one of the significant risk factors for the development of diabetic nephropathy in NIDDM patients.

Age of Onset↗
PubMed1993

Deletion mapping of chromosome 3p in human uterine cervical cancer.

Deletion mapping of chromosome 3p was performed on 47 cases of human uterine cervical cancer using 24 polymorphic DNA markers including five inter-Alu DNA markers and two NotI-boundary cosmid markers obtained in our laboratory. The most likely order of these 24 polymorphic DNA markers was determined as being cen-[D3S4, H8]-D3S693-D3S659-D3S30-D3S687-[D3S2, UR9, UR47]-J36-J17-GNAI2B-D3F15S2-D3S643- D3S32-D3S23-D3S686-H35-UR189-D3S685-D3S 11 - D3S12-THRB-D3S22-pter, based on the data from radiation hybrid mapping genetic linkage analysis and in situ hybridization. Loss of heterozygosity (LOH) at one or more loci on chromosome 3p was detected in 21 of 47 cases (45%). Four tumors showed partial or interstitial deletions, and the common region of LOH in these tumors was 3p13-p21.1 between the D3S30 marker and the D3S2 marker. Candidates for tumor-suppressor genes, APEH, D8, GNA12B, ZNF35, RARB, THRB and RAFI, were all mapped outside of the common region in uterine cervical cancer. However, this region is commonly deleted in carcinoma of the lung, breast and kidney, and encompasses the breakpoint of the (3;8) translocation in hereditary renal cell carcinoma. This result indicates the presence of a novel tumor-suppressor gene in the region of 3p13-p21.1, which is involved in the development of several human cancers.

Base Sequence↗
PubMed1993

[Recent trends in human immunodeficiency virus (HIV) infection and anti-HIV testing in foreign residents in Japan].

To explore the recent situation of the human immunodeficiency virus (HIV) epidemic in foreign residents in Japan, a survey of medical records between 1989-1992 was performed in a clinic located in a small district of Tokyo metropolitan area where foreign prostitutes were relatively concentrated. From medical records results of laboratory tests for HIV, syphilis, gonorrhea and chlamydial infection were collected. The present study revealed (1) that more than 1000 foreigners, of whom the majority were Thai, with a female to male ratio over 10, visited the clinic during the 4 years with a marked increase from 1990 to 1991, (2) that among the laboratory tests only anti-HIV testing rate markedly increased by 2-3 fold from 1990 to 1991 in both sexes (3) that anti-HIV seropositives were 41 in total (F = 39, M = 2), around 4% in both sexes, with a slight increasing trend in females and particularly high infection rate (14.0%) in females aged < 20 and (4) that no significant correlation was observed between HIV infection and other sexually transmitted diseases. These results suggest that the remarkable increase witnessed by the recent AIDS surveillance in Japan could have been influenced at least in part by the sudden increase in the testing rate for anti-HIV as well as by the increase in the number of foreigners visiting clinics. It also suggests the critical importance of targeting foreign females of high risk behaviour in the AIDS prevention strategies in Japan since HIV infection rates were high among foreign females, especially in teenagers.

AIDS Serodiagnosis↗
PubMed1993

Immunofluorescent analysis of extracellular matrix (ECM) components in glomeruli of the hepatic glomerulosclerosis.

An immunofluorescence study was carried out to evaluate alterations in the distribution and/or intensity of extracellular matrix (ECM) components, immunoglobulins and complement (C3) in the glomeruli of 7 autopsy patients with hepatic glomerulosclerosis. As compared with the findings in normal renal tissues, an increase in type IV collagen, laminin and fibronectin was observed in expanded glomerular mesangial areas and along glomerular capillary walls. Depositions of IgA, mainly IgA1, and C3 in glomeruli were in parallel with those of the ECM components. These ECM components were markedly decreased in glomeruli showing global sclerosis. In contrast, type I collagen was observed at central portions of the sclerotic glomeruli. There was an increase in the type I collagen along Bowman's capsules, especially at the sites of capsular adhesion and crescent formation. It appears that hyperproduction and/or infiltration of glomerular ECM components and interstitial collagen is closely linked to the progression of glomerular sclerosis in patients with liver diseases.

Adult↗
PubMed1993

[A case of epidural hematoma caused by a vacuum extraction without any skull fractures and accompanied by cephalohematoma].

A case of epidural hematoma associated with cephalohematoma caused by a vacuum extraction was reported. Old liquefied hematoma was removed via a small burr hole in the parietal bone at the age of 23 days. No neurological deficits were recognized at the age of 6 months. As the dura mater does not easily detach from the overlying skull in the neonate, it is a very rare occurrence for this to happen as a complication of the use of forceps or in extractions. To our knowledge, only 4 cases of epidural hematoma after vacuum extraction have been reported. The mechanism of the development of an acute epidural hematoma during extraction is reported to be due to direct force to the dura mater and skull induced by negative pressure of a vacuum extraction. In the present case, it seems that negative pressure produced a detachment of the dura mater from the overlying skull. It suggests that examinations including plain craniogram and CT scan should be performed as soon as possible in the neonate with cephalohematoma when they have been delivered by a vacuum extraction.

Bone Diseases↗
PubMed1993

[Heart failure due to metabolic heart disorders].

The classification of myocardial diseases, proposed by the WHO/ISFC task force in 1980, distinguishes specific heart muscle diseases from myocardial diseases of unknown origin, termed cardiomyopathies. In this article, specific heart muscle diseases caused by metabolic disturbances are reviewed. The disorders were categorized into 4 types: 1. endocrine disorders; 2. storage or infiltration disorders, such as amyloidosis, hemochromatosis and familial storage disorders; 3. nutritional disorders, such as Kwashiorkor, beri-beri, obesity and alcoholic and electrolyte disorders; and 4. Diabetic heart. Since the first type disorders have been covered by a separate review, the other 3 types were covered in this article. A common clinical picture of these disorders is chronic congestive heart failure. The pathogenesis and laboratory findings of these disorders are briefly discussed.

Amyloidosis↗
PubMed1993

[A case of left ventricular aneurysm associated with acromegaly].

We performed a left ventricular aneurysmectomy for a left ventricular aneurysm associated with acromegaly in a 62-year-old man. Bromocriptine mesilate was administered to suppress high growth hormone (GH) levels, and there were no complications during or after the operation. The majority of patients with acromegaly die of cardiovascular diseases such as cardiomegaly, hypertension, arteriosclerosis of the coronary arteries, congestive heart failure, valvular disease, and arrhythmia. Ventricular aneurysm is a rare complication of acromegaly. In order to safely operate, it is important to control serum GH levels and pay special attention to the well-known complications of acromegaly such as diabetes mellitus and hypertension.

Acromegaly↗
PubMed1993

Morphometric analysis of subchondral bone of the tibial condyle in osteoarthrosis.

Tibial condyles in 11 patients with knee joint osteoarthrosis were analyzed by subchondral bone morphometry using 11 static parameters. The results were evaluated by comparison with the grade of joint cartilage degeneration in relation to the external, intermediate, and internal areas of the tibial condyle. The bone morphometric data also were analyzed according to the depth of layers, from the surface to the depth of 2000 microns of the bone. A parallel relationship between the bone volume/bone formation activity and the Mankin grade of cartilage degeneration was noted in both medial and lateral condyles. Bone resorption activity in the medial condyle was found only in the external and intermediate areas; it was extremely low in the lateral condyle. Throughout the observation areas, the values of bone volume in relation to depth were highest in the superficial layer with a gradual decrease as the depth increased. The bone formation activity was highest in the superficial layer in the lateral condyle, whereas in the medial condyle, it was highest in the layer between 1000 and 1500 microns in depth. The bone resorption activity showed no variations according to the depth. The progression of joint cartilage degeneration was associated with remodeling of the underlying subchondral bone.

Aged↗
PubMed1993

[Current status of transfusion-transmitted infection].

Recently transfusion-transmitted infections (TTI) have been decreased remarkably. Especially nonA, nonB posttransfusion hepatitis (PTH) has reduced to one third by introducing anti-HCV (C100-3) antibody screening. HCV-PTH will be lowered more with screening by the 2nd generation reagent of HCV. None of cases with HIV infection by transfusion has been reported since introduction of anti-HIV antibody screening, but we have to watch out it, due to rapid increase of heterosexual infection of HIV during this one year in Japan. Voluntary blood donors should warrant blood safety by their own responsibility. We have no cases with malaria by transfusion for these several years. There are no reported cases with Chagas' disease in Japan, but increase of international immigrations will be potential to introduce these infections by transfusion into Japan. Recently TTI by bacteria-contaminated blood have been very rare owing to technical improvement of blood-drawing. However, platelet concentrates stored at 22 degrees C for 3-5 days and red cell products stored at 4 degrees C for 35-42 days have presented new problems concerning bacterial contamination. We have to consider these problems concerning bacterial contamination.

Blood Donors↗