Biomedical subjects

T Takashima

Publications and source records attributed to T Takashima.

At least 127 records · Page 7Linked to original sources

PubMed1995

Biochemical characterization of the fibres of collagen and elastin in the aortic wall of SHRSP.

1. Vessel wall fragments consisting of collagen, elastin and other insoluble proteins were prepared from the aortas of 6 month old WKY and SHRSP and dead, elderly humans. 2. Prolonged incubations of these fragments with pepsin below or at 30 degrees C resulted in different amounts of insoluble materials containing similar or larger proportions of collagen and other insoluble proteins than the respective vessel fragments. The amounts of the pepsin-insoluble materials obtained from SHRSP were larger than those from WKY but were much smaller than those from elderly humans. 3. The elastins isolated from the vessel fragments were solubilized by pepsin much more effectively than the respective vessel fragments. 4. The pepsin-insoluble materials from WKY were composed of thin mesh-shaped materials, while these materials from both rats did not contain a significant number of distinctive fibrils of collagen, the materials from elderly humans did contain numerous distinctive fibrils of collagen. 5. Large fractions of both the collagen and other proteins in the pepsin-insoluble materials were solubilized by incubation with a crude bacterial collagenase below 30 degrees C or by incubation with pepsin above 40 degrees C where the triple-helical regions of the collagens were unfolded. 6. These results appear to indicate that the aortic wall of SHRSP contains larger amounts of some insoluble components that immobilize the collagen fibrils than that of WKY, but the aortic walls of elderly humans contain much larger amounts of these components than that of SHRSP.

Aged↗

PubMed1995

Hepatocellular carcinoma: CT appearance of parenchymal changes after percutaneous ethanol injection therapy.

PURPOSE: To evaluate the changes in surrounding liver parenchyma after treatment of hepatocellular carcinoma (HCC) and borderline malignant lesions with percutaneous ethanol injection (PEI). MATERIALS AND METHODS: The authors reviewed the findings at computed tomography (CT) and CT during arterial portography (CTAP) obtained before and after PEI therapy for 32 lesions in 26 patients with HCC or adenomatous hyperplasia. Two surgically resected specimens were also histologically examined. RESULTS: In 10 (77%) of 13 lesions, decreased portal vein-related enhancement indicative of reduced portal blood flow in the periphery of the tumor was found at CTAP. Mild atrophy (concave liver surface), segmental atrophy, and lobar atrophy were found in 40%, 17%, and 3%, respectively. Histologic examination of the resected specimens revealed organized thrombi in the peripheral portal vein in the surrounding liver. CONCLUSION: PEI may cause decreased portal blood flow and atrophy in the noncancerous liver parenchyma that surrounds the tumor being treated.

Aged↗

PubMed1995

Aberrant gastric venous drainage in cirrhotic livers: imaging findings in focal areas of liver parenchyma.

PURPOSE: To analyze imaging finding in focal areas of liver parenchyma with aberrant gastric venous drainage (AGVD) in cirrhotic livers. MATERIALS AND METHODS: Eighteen patients with AGVD confirmed with computed tomography (CT) during arterial portography and arteriography underwent ultrasound (US) (n = 18), CT (n = 18), magnetic resonance (MR) imaging (n = 12), dynamic CT (n = 14), and dynamic MR imaging (n = 8). Imaging and histologic (n = 2) findings were analyzed. RESULTS: The focal area with AGVD was hypoechoic on US scans (n = 7), hypoattenuating on CT scans (n = 4), hyperintense on T1-weighted MR images (n = 6), and hypointense on T2-weighted MR images (n = 5). Early enhancement was seen with dynamic CT (n = 8) and with dynamic MR imaging (n = 6), without definite staining on arterial phase of arteriography. Histologic findings revealed hyperplastic changes of liver. CONCLUSION: The imaging findings, except for early enhancement, were very similar to those of adenomatous hyperplasia or well-differentiated hepatocellular carcinoma. The early enhancement was considered due to early venous return compared with that of the surrounding liver.

Adenoma↗

PubMed1995

Subclavian steal phenomenon associated with stress polycythemia. A case report.

A case of stress polycythemia without symptoms of cerebral ischemia is presented. The patient demonstrated a blood flow reversal through the right vertebral artery that was caused by a complete obstruction of the right subclavian artery at its origin. This obstruction may have been due to thrombosis associated with stress polycythemia. This is a rare example of a case in which thrombotic complications of stress polycythemia occurred in a larger caliber vessel such as the subclavian artery.

Humans↗

PubMed1995

Urine C-peptide and atherogenic risk factors in diabetes mellitus: relevance to "syndrome X".

The relation between the C-peptide concentration in twenty-four-hour urine specimens and atherogenic risk factors was investigated in 38 patients with noninsulin-dependent diabetes mellitus in an attempt to determine the significance of urine C-peptide in diagnosing "syndrome X," which is characterized by insulin resistance. Weak positive correlations between twenty-four-hour urine C-peptide concentration and body mass index, systolic blood pressure (BP), diastolic BP, serum total cholesterol, and serum triglyceride were detected. A weak negative correlation was also apparent between urine C-peptide and serum high-density lipoprotein (HDL). The body mass index and serum triglyceride of patients with urine C-peptide excretion of > 100 micrograms/day were significantly higher than those in patients with normal urine C-peptide excretion (< 100 micrograms/day) (P < 0.01 and P < 0.02, respectively). Systolic BP, diastolic BP, serum total cholesterol, and serum HDL did not differ significantly between the two groups of patients. Results indicate that twenty-four-hour urine C-peptide concentration is of significance in determining whether a patient has a tendency to insulin resistance but has only limited value as a quantitative measure of endogenous insulin secretion.

Adult↗

PubMed1995

Gadolinium-enhanced magnetic resonance imaging of meningeal carcinomatosis in colon cancer.

Meningeal carcinomatosis has been infrequently reported in colorectal carcinoma. Recently the value of gadolinium-enhanced magnetic resonance imaging (MRI) in the examination of this disease has been described. We report a 55-year-old man with meningeal carcinomatosis from a known colon cancer. In this case, a gadolinium-enhanced MRI of the brain showed enhancing dura and nodular lesions which were not detected by enhanced computed tomography. The gadolinium-enhanced MRI may serve as an indicator of leptomeningeal involvement and may be a useful test in addition to the evaluation of cerebrospinal fluid cytology and chemistry.

Carcinoma↗

PubMed1995

Focal sparing of segment IV in fatty livers shown by sonography and CT: correlation with aberrant gastric venous drainage.

OBJECTIVE: One of the most common sites of focal sparing in fatty livers (focal spared area) shown by sonography or CT is the posterior edge of segment IV. The differentiation of such a focal spared area from tumor has been a diagnostic challenge. The purpose of this study was to determine if a correlation exists between the focal spared area at the posterior edge of segment IV in fatty liver and the decrease of portal perfusion from the main portal vein due to aberrant gastric venous drainage directed into segment IV. SUBJECTS AND METHODS: Seventeen patients with fatty liver diagnosed on the basis of sonographic and CT findings who had hepatic arteriography and/or CT during arterial portography (CTAP) were included in the study. Seven patients had a focal spared area more than 2 cm in the longest diameter at the posterior edge of segment IV, and 10 patients did not have a focal spared area. The frequency of aberrant gastric venous drainage shown by arteriography (17 patients) and/or by CTAP (15 patients) was compared in the two groups of patients. RESULTS: Hepatic arteriography showed aberrant gastric venous drainage in all patients who had a spared area, and CTAP showed a portal perfusion defect at the posterior edge of segment IV in all five patients with a focal spared area who underwent CTAP. On the other hand, no definite aberrant gastric venous drainage and portal perfusion defect were seen in any patient without a spared area. The difference in the frequency of aberrant gastric venous drainage between the two groups of patients was statistically significant (chi-square test, p < .0001). CONCLUSION: Our results show that a strong correlation exists between the focal spared area at the posterior edge of segment IV in fatty liver and aberrant gastric venous drainage directed to segment IV. Focally decreased blood flow from the main portal vein associated with aberrant gastric venous drainage is a likely cause of the focal spared area. This fact is important for the differential diagnosis of hepatic tumors.

Adult↗

PubMed1995

[Effect of copper and copper binding protein on the CT attenuation value of liver: experimental study in rats].

We analyzed the effect of copper and copper binding protein on CT attenuation value in a rat model. CT attenuation values of the liver were compared with hepatic copper content and grade of orcein-positive granules, which are thought to be a counterpart of polymerized methalothionein in lysosomes. The difference between hepatic copper and CT attenuation value was not statistically significant (R = 0.056, p = 0.96). CT value had a positive correlation with the grade of orcein-positive granules (Rho = 0.755, p = 0.0001). We concluded that the CT attenuation value of liver can be elevated by rich polymerized methalothionein (copper binding protein) in lysosomes.

Animals↗

PubMed1995

[Thoracoscopic debridement for acute empyema].

Thoracoscopic debridement for acute empyema was successfully performed in three patients who were refractory to closed drainage, irrigation and antibiotic therapy. In two patients anaerobic organisms were isolated from the pus. None of the patients had bronchopleural fistula. All patients were relieved of fever promptly after surgery. Operative invasion was minimal, and postoperative lung function was well maintained one month after the operation. If empyema is in the fibrinopurulent phase and does not respond to pleural drainage, thoracoscopic debridement may be indicated before more aggressive therapy.

Acute Disease↗

PubMed1995

[Experimental study on embolic materials for simultaneous segmental embolization through transarterial route].

To determine suitable embolic materials for simultaneous arterioportal embolization through the arterial route, transcatheter arterial embolization (TAE) using iodized oil (Lipiodol) mixed with monomeric n-butyl-2-cyanoacrylate, with absolute ethanol, or mixed with Gelfoam powder was carried out in 14 dogs. Following TAE, the distribution of Lipiodol in hepatic artery, peribiliary plexus, and portal vein was analyzed by soft tissue x-ray radiography and en bloc silver impregnation. As a result, Lipiodol mixed with absolute ethanol, and Gelfoam powder was considered to be the most reasonable embolic materials for this purpose.

Animals↗

PubMed1994

Fetal urine production at different gestational ages: correlation to various compromised fetuses in utero.

To reveal which fetal life-threatening diseases significantly contribute to impairment of in-utero urine production and also to determine the gestational age at which time aberrant urine production becomes manifest, we observed 376 compromised fetuses (subject group) at 21-42 weeks' gestation using ultrasonography. A total of 358 uncomplicated fetuses, aged 21-40 weeks, were separately chosen as a control group. Statistical differences in the urine production rate between subject- and control-group fetuses were analysed using the Grubbs-Smirnoff test at corresponding gestational ages. Significant decreases were evident in: bilateral renal agenesis (100%) at 21-23 weeks; bilateral infantile polycystic kidney (100%) at 21-28 weeks; bilateral multicystic kidney disease (100%) at 21-31 weeks; donor fetuses with twin transfusion syndrome (TTS) (100%) at 21-28 weeks; post-term fetuses (100%) at 42 weeks; bilateral hydronephrosis (60%) at 21-38 weeks; non-immunologic hydrops fetalis (42%) at 21-35 weeks; intrauterine growth retardation (41%) at 29-40 weeks; and upper gastrointestinal tract obstruction (36%) at 30-38 weeks. Significant increases were noted in: recipient fetuses with TTS (100%) at 21-28 weeks, and unilateral hydronephrosis (36%) at 27-32 weeks. All indicate that urine production clearly delineates various fetal conditions in utero, in a closely disease-dependent relation to gestational age.

Diuresis↗

PubMed1994

Nonrandom chromosomal rearrangements of 14q32.3 and 19p13.3 and preferential deletion of 1p in 21 patients with multiple myeloma and plasma cell leukemia.

Structural chromosomal abnormalities and their break-points were characterized in 17 patients with multiple myeloma (MM) and 4 with plasma cell leukemia by banding. Chromosome 14q32 translocations with a variety of partners were detected in 13 patients, and a variant translocation t(8;22)(q24.1;q11) was detected in 1. Three recurrent 14q32 translocations have been identified: t(6;14)(p21.1;q32.3) occurring in 3 cases, and t(11;14)(q13;q32.3) and t(14;18) (q32.3;q21.3) each occurring in 2 cases. Translocations t(1;14)(q21;q32.3), t(3;14)(p11;q32),t(7;14)(q11.2;q32.3), and t(11;14)(q23;q32.3) were found in each patient, whereas in the remaining 2 patients, partner chromosomes could not be determined. The band 19p13.3 was newly delineated as a recurrent breakpoint involved in translocations in MM. Chromosomes 1 and 6 were also commonly involved in structural abnormalities (14 and 10 patients, respectively), although no particular bands were noted. However, the short arm of chromosome 1 was preferentially involved in deletion, suggesting a certain antioncogene on 1p associated with the development of myeloma. In addition; fluorescence in situ hybridization was successfully applied to determine the nature of the structural abnormalities in a patient with t(8;22) translocation. The present findings suggest that there may be subsets of 14q32 translocations specific to MM.

Adult↗

PubMed1994

What is the minimum number of heart rates necessary to evaluate fetal conditions at different gestational ages?

Our objective was to determine the minimum number of fetal heart rates (FHRs) needed to assess various fetal conditions adequately, focusing on FHR changes in relation to gestational age. We used probability distribution matrices previously derived from 10,934,604 FHRs of 743 uncomplicated fetuses. These matrices were made at nine consecutive 2-week intervals between 23 and 40 weeks' gestation, from which samples were taken after assigning random numbers to FHRs in sequence. As a variable, the difference rate (%) between the sample probability distribution matrix and its corresponding age-group probability distribution matrix was calculated. Scattergrams of difference rates vs. a given number of FHR samplings were analyzed using piecewise linear regression. One critical point per age-group emerged, ranging between 9000 and 10,000 beats, for all age-groups. A linear decrease in the difference rate was noted with a step-by-step increase in random sampling size of FHRs until reaching the critical point, beyond which the difference rate remained constant between 25-33%. The critical points indicate that the minimum number of FHRs for assessment of the fetus at 23-40 weeks' gestation is almost the same, between 9000 and 10,000, with 67-75% baseline variability (so called beat-to-beat variability) and 25-33% long-term variability regardless of advance in gestation.

Evaluation Studies as Topic↗

PubMed1994

Detection of 14q32 translocations in B-cell malignancies by in situ hybridization with yeast artificial chromosome clones containing the human IgH gene locus.

Partner sites of 14q32 translocations found in B-cell malignancies were detected by fluorescence in situ hybridization (FISH) using yeast artificial chromosome (YAC) clones, Y20 and Y6, containing the human Ig heavy chain (IgH) gene locus. Y20 spans a 160-kb upstream and 40-kb downstream region of the JH segments on chromosome band 14q32.33. Y6 is 300-kb upstream of Y20, and spans a further 320-kb telomeric region. The human DNA sequences amplified by Alu polymerase chain reaction of the YAC clones were used as probes for FISH to study six patients with non-Hodgkin's lymphoma (NHL), one patient with acute lymphoblastic leukemia, and one cell line FR4 established from a plasmacytoma. Three telomeric YAC clones each specific for 3q, 8q, and 18q were also used to further characterize 14q32 translocations. The IgH YACs were successfully applied to detect cytogenetically invisible subtelomeric translocation of the IgH gene locus to each partner site in t(14;18), t(8;14), and t(14;19), and to identify t(3;14) (q27;q32.33) in three patients with 14q32 translocation of unknown origin. Furthermore, complex translocations involving more than three chromosomes were detected in an NHL patient with t(8;14), and t(3;12), and in the FR4 with der(14)t(8;14), der(8)dic(1;8), and del(1)(q21). The technique would be a useful tool in elucidating the mechanisms of a 14q32 translocation in B-cell malignancies.

Aged↗

PubMed1994

[Dual-energy subtraction technique with FCR: clinical application for diagnosis of pulmonary vascular diseases].

The use of dual-energy techniques has already proved to be beneficial in nodule detection and characterization of the calcification in nodules. Other clinical applications, in which simplification of the background might lead to improved results, should be investigated. We evaluated the image quality of pulmonary vessels in the dual-energy techniques with FCR. In visualization of the pulmonary vessels of normal patients, dual-energy soft tissue images were equal or inferior to the original unsubtracted digital images because of increased noise. In the diagnosis of some pulmonary vascular diseases (e.g., Takayasu's arteritis), however, soft tissue images resulted in improved conspicuity of involved sites compared with the unsubtracted images.

Adult↗

PubMed1994

Subsegmental transcatheter arterial embolization for small hepatocellular carcinomas: local therapeutic effect and 5-year survival rate.

The local therapeutic effects and 5-year survival rates obtained following subsegmental transcatheter arterial embolization (TAE) therapy for small hepatocellular carcinomas (HCCs) were retrospectively analyzed. A total of 124 nodular-type HCC lesions measuring less than 4 cm in diameter in 100 patients with liver cirrhosis were subjected to the analysis. All lesions became opaque on digital subtraction angiography. Complete necrosis was seen in 64% of 11 resected lesions. Among the remaining 113 lesions, the 1- and 5-year local recurrence rates following one performance of TAE were 18% and 33%, respectively. The 1- and 5-year survival rates were 100% and 53%, respectively. No significant side effect was observed after TAE therapy. Subsegmental TAE therapy significantly improved the long-term survival rates of patients with small HCCs associated with liver cirrhosis as compared with those treated by conventional TAE therapy.

Adult↗

PubMed1994

Fetal heart rate variation described using a probability distribution matrix.

We devised a new method using a probability distribution matrix to simultaneously describe variation in the characteristics of fetal heart rate (FHR) and beat-to-beat difference (DFHR) between the present and the immediately following FHR. The FHRs were plotted in columns, DFHRs in rows and probabilities in the corresponding elements of the matrix. The age-related changes of FHR data obtained from 743 fetuses at 23-40 weeks gestation were analysed using a pulsed Doppler cardiotocograph with an autocorrelation system. While keeping an almost symmetrical spread around 0 beats/min of DFHR, three particular probability distribution patterns of FHR versus DFHR emerged with advance in gestation: (i) oval with a monomodal peak from 23/24 to 29/30 weeks, (ii) ellipsoid with a monomodal peak and plateau from 31/32 to 33/34 weeks and (iii) elongated ellipsoid with bimodal peaks from 35/36 weeks of gestation onwards. The probability distribution matrix presented enables one to condense any amount of FHR data into one uniform description. This allows analysis of data, en bloc, achieving a quantitative inter-group comparison, on an equivalent scale.

Age Factors↗

PubMed1994

The relationship between age-related heart rate changes and developing brain function: a model of anencephalic human fetuses in utero.

We attempted to identify the brain segment which controls heart rate changes in human fetuses with advancing gestation. Twelve anencephalic and 165 normal fetuses (control-group fetuses) between 25-32 weeks' gestation were studied. The instantaneous fetal heart rate (FHR) data were obtained from each fetus for a continuous 90-120 min period, using an external cardiotocograph. Calculations included the 'individual probability distribution matrices' in which the FHRs at 1 beat/min intervals between 110 and 180 beats/min, the beat-to-beat differences (DFHRs) between +/- 5 beats/min and the probability values were arranged in rows, columns and the corresponding elements, respectively. Using 2-gestational-week intervals probability distribution matrices (age-group probability distribution matrices) obtained from 335 normal fetuses in our previous study as a reference, the difference between a given 'individual probability distribution matrix' and the corresponding age-group probability distribution matrix' was quantified as the 'difference rate' according to the formula in the text. From 25-26 to 27-28 weeks' gestation, the 'difference rates' in four anencephalic fetuses, with only the spinal cord preserved, were significantly higher in value than those of control-group fetuses, whereas the rates in four fetuses with both the spinal cord and medulla oblongata preserved, indicated no significant differences. From 29-30 to 31-32 weeks' gestation, the rates of the four fetuses with the spinal cord and medulla oblongata preserved, showed significant differences from the control-group fetuses. These findings suggest that there is a critical period between 27-28 and 29-30 weeks' gestation with regard to the developing brain function pertaining to FHR changes. In the early stage, the medulla oblongata plays a role in FHR changes, whereas, in the latter stage, the brain cephalad to the medulla also appears to take on the role of FHR regulator.

Anencephaly↗