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T Koyanagi

Publications and source records attributed to T Koyanagi.

At least 217 records · Page 12Linked to original sources
PubMed1994

[Seventy-seven coronary reoperations: incidence, indication and results].

As the number of patients who have undergone primary myocardial revascularization continues to burgeon, the number of potential candidates for a secondary myocardial revascularization has increased gradually. The number of secondary CABG at the Cleveland Clinic were performed, which represents 18% of the total CABG. However, the number of secondary CABG at The Heart Institute of Japan were performed, which represents of 5-10% of the annual CABG. There was one operative death (1.3%). The graft patency rate was 92.8%. Including non-cardiac death, the actuarial survival rate at 10 years was 88.2%, and events free rate including all deaths, the third time CABG, PTCA and myocardial infarction was 78.4% at 10 years.

Adult↗
PubMed1993

Predictability of operative results of cervical compression myelopathy based on preoperative computed tomographic myelography.

The transverse area and flattening ratio of the spinal cord were determined with preoperative computed tomographic myelography in 103 patients with cervical compression myelopathy: cervical spondylotic myelopathy (n = 44); ossification of the posterior longitudinal ligament (n = 39); and cervical disc herniation (n = 20). With these values and other clinical items (eg, age, duration of symptoms, preoperative severity), a linear model to predict postoperative recovery was attempted by multiple regression analysis. In cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament, the transverse area of the spinal cord and the duration of symptoms were accepted as effective explanatory variables to predict recovery. In cervical disc herniation, regardless of the transverse area or duration, the recovery was good, and pathologic state was considered essentially different.

Cervical Vertebrae↗
PubMed1993

Fetal eye movements.

Since 1981, when eye movements of the human fetus were first reported, the study of fetal eye movements has increased, mainly focusing on the ontogenesis of eye movements and as one parameter of behavioral states. Using real-time ultrasound, fetal eye movements can be clearly observed from 14 weeks of gestational age. Fetal eye movements may be described in terms of their pattern, frequency and incidence of periods containing eye movements and no eye movements. Furthermore, the relationship of eye movements to other behaviors may be used to give information on the integration of central nervous system function. A picture of normal fetal eye movements can be constructed and used to detect abnormalities in eye movements which can indicate underlying abnormalities of the central nervous system. This paper concludes that, although in its early stages, the study of fetal eye movements holds promise for a greater understanding of brain development and the assessment of the condition of the fetus.

Journal Article↗
PubMed1993

Identification of androgen receptor in the rat spinal motoneurons. Immunohistochemical and immunoblotting analyses with monoclonal antibody.

Androgens play an important role in motoneuron growth, development and regeneration. We proved the existence of androgen receptor (AR) in the motoneurons of the rat spinal cord by the immunohistochemical stain and Western blotting. The possibility that AR protein in spinal cord is expressed in tissue-specific form is proposed, being different from other androgen-dependent tissues. AR abnormality in X-linked spinal and bulbar muscular atrophy (SBMA) among a variety of motor neuron diseases were reported recently. Our study may give some clue to the AR abnormality leading to the degeneration of motoneurons.

Animals↗
PubMed1993

Susceptibility of renal tubular cells to lymphokine-activated killer (LAK) cells: application of culture system using a collagen gel matrix.

Monolayer cultures of renal tubular (hKEC) cells were established. These cells formed empty spheroids after 2-3 weeks of culture in a collagen gel matrix. A subcellular polarity from the apex to basement was induced in these "spheroidal" hKEC cells. The weak expression of laminin at the outer surface was evident on spheroidal but not on monolayered hKEC cells. The regulation of HLA-ABC, DR, and intercellular adhesion molecule-1 (ICAM-1) antigens on hKEC cells in the gel matrix was investigated utilizing digestion of gel matrix by collagenase. Enzymatic digestion of the collagen gel did not significantly affect the surface expression of HLA-ABC and ICAM-1, but reduced HLA-DR expression as shown by flow cytometry. The MHC and ICAM-1 molecules on both spheroid-forming and monolayered hKEC cells were upregulated by adding a supernatant of mixed lymphocyte reaction (MLR) and recombinant human interferon (IFN)-gamma. HLA-DR antigen expression was inconsistently induced on the hKEC cells cultured in collagen gel without MLR supernatant or IFN-gamma. In contrast, no HLA-DR expression was found on monolayered hKEC cells in the absence of MLR supernatant or IFN-gamma. Spheroid-forming hKEC cells, when dispersed by enzymatic digestion, were more susceptible to cytolysis by lymphokine-activated killer (LAK) cells than were the enzymatically dispersed, monolayered cells in the 51Cr-release assay. The LAK cells were seen to migrate into the collagen gel and kill the hKEC cells. Thus, LAK cells may function to favor the acceleration of graft rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Surface↗
PubMed1993

Cecoureterocele: experience of three cases with special reference to the relevance of endoscopic incision.

We report three cases of cecoureterocele to emphasize the salient features of this rare clinical entity. The differentiation of it from the usual ectopic ureterocele requires careful examination of the urethra by voiding cystourethrography and cystourethroscopy. We describe the management of these three cases with special reference to the endoscopic incision of the obstructing tissue.

Child↗
PubMed1993

Clinical experience of incidentally discovered adrenal tumor with particular reference to cortical function.

We reviewed 14 male and 9 female patients with adrenal tumor discovered incidentally by imaging studies in an attempt to assess adrenal function, mainly cortical function. Pathological diagnosis consisted of cortical adenoma in 12 patients, cortical nodular hyperplasia in 2, medullary hyperplasia in 1, cavernous hemangioma in 1, metastatic tumor in 4 and cyst in 2. Another adrenal cyst was diagnosed by percutaneous puncture. In all patients peripheral levels of plasma cortisol and aldosterone were normal. Plasma catecholamine levels were also normal except for 1 patient with medullary hyperplasia who had equivocal elevation. Among the patients with cortical adenoma and hyperplasia, however, 5 of 10 (50%) had excessive excretion of 24-hour urinary 17-hydroxycorticosteroids, 4 of 13 (31%) had a loss of plasma cortisol circadian rhythm and 7 of 14 (50%) had insufficient suppression on the dexamethasone test. Furthermore all patients had an increased ipsilateral uptake that was not suppressed after dexamethasone on 131iodine-adosterol scintigraphy, while a diminished contralateral uptake was noted in 5 of 15 (33%). Postoperatively, hypertension decreased to normal in 2 of 3 patients and impaired glucose tolerance was improved in 1 of 2. Two patients with cortical adenoma who exhibited a loss of plasma cortisol circadian rhythm experienced postoperative adrenal insufficiency. These data indicate that a considerable number of incidentally discovered adrenal tumors are not nonfunctioning particularly in reference to glucocorticoid secretion, and adrenalectomy seems to be beneficial in some of those patients with hypertension or impaired glucose tolerance.

17-Hydroxycorticosteroids↗
PubMed1993

Radionuclide constant pressure perfusion study on measurement of exit urine flow: experimental and preliminary clinical investigations.

To calculate exit urine flow from the renal pelvis to the bladder in hydronephrosis, a simple method, radionuclide constant pressure perfusion study, was used. The mathematical model proposed for calculation of the exit flow (F) was simple: F = (initial slope)/Do'/exp(-0.148d), where F is expressed as flow rate (ml. per minute) of infused radioactive solution into the bladder. The value of the initial slope is expressed as a count rate per minute of time-activity curve of the bladder. Do' is a count rate per ml. of infused radioactive solution, which was measured by a gamma camera in air, and d is depth (cm.) of the bladder from the body surface to the vesical mucosa. The number -0.148 indicates the effective linear attenuation coefficient of 99mtechnetium, which was determined by a phantom study. In the experimental studies calculated flow correlated well with real pump flow. In preliminary clinical studies in 16 patients (20 kidneys) who underwent nephrostomy, measurement of flow rate at steady intrapelvic pressure with no subtraction of intra-abdominal pressure in 12 of 14 nonobstructed cases demonstrated a pressure-dependent pattern in which flow increased linearly in response to the pressure increase. In 2 nonobstructed children radionuclide constant pressure perfusion study failed: 1 due to crying and 1 to unknown causes. In 2 cases of complete or equivocal obstruction by constant perfusion (Whitaker test) only minimal or no flow rate was found at the maximum intrapelvic pressure increase of 24 cm. water. The urine flow was observed only in the repeated study in 3 patients. These phenomena were assumed to be due to immature expertise in the new technique. This new technique can provide physiological measurement of the urine flow at variable levels of constant intrapelvic pressure in hydronephrotic patients, although the pressure-flow relationship for identifying partial obstruction from nonobstruction still remains to be clarified in further clinical studies.

Adolescent↗
PubMed1993

Measurement of prostate specific antigen and gamma-seminoprotein ratio: a new means of distinguishing benign prostatic hyperplasia and prostate cancer.

We measured a ratio of serum prostate specific antigen (PSA) and gamma-seminoprotein concentrations (referred to as the PSA/gamma-seminoprotein ratio) and evaluated its usefulness for the diagnosis of prostate cancer. Between April 1988 and October 1992, 214 men underwent prostatic biopsy and/or transurethral resection of the prostate, and the disease was diagnosed pathologically. Of 214 patients 127 were diagnosed as having benign prostatic hyperplasia, prostatitis or a normal prostate (no cancer), while 87 had prostate cancer. Of 61 patients with a serum PSA level greater than 10 ng./ml. 50 (82.0%) had prostate cancer, compared to 31 of 84 (36.9%) with a serum PSA level of 3.0 to 10 ng./ml. Of 113 patients with a serum gamma-seminoprotein level greater than 4.0 ng./ml. 52 (46.0%) had prostate cancer. The mean plus or minus standard deviation of the PSA/gamma-seminoprotein ratio for 127 patients without cancer was 0.942 +/- 0.564, while that for 87 prostate cancer patients was 12.840 +/- 45.327 (Wilcoxon p < 0.0001). The mean plus or minus standard deviation of the PSA/gamma-seminoprotein ratios for 37 prostate cancer patients with a PSA level of 10 ng./ml. or less and for 50 prostate cancer patients with a PSA level of more than 10 ng./ml. were 2.044 +/- 0.767 and 20.829 +/- 58.757, respectively. Even the mean PSA/gamma-seminoprotein ratio for prostate cancer patients with a PSA level of 10 ng./ml. or less was significantly greater than that for patients without cancer (Wilcoxon p < 0.0001). The sensitivities for PSA (cutoff value 3.0 ng./ml.), gamma-seminoprotein (cutoff value 4.0 ng./ml.) and PSA/gamma-seminoprotein ratio (cutoff value 1.45) were 93.1%, 59.8% and 92.0%, respectively, and the specificities were 49.6%, 52.0% and 91.3%, respectively. Of 91 patients with a PSA/gamma-seminoprotein ratio of 1.45 or more 80 (87.9%) had prostate cancer, while 116 of 123 (94.3%) with a PSA/gamma-seminoprotein ratio of less than 1.45, had no cancer. These results suggest that PSA/gamma-seminoprotein ratio yields the same sensitivity as PSA and more specificity than PSA levels, offering significant advantage over PSA in detecting prostate cancer. The mean plus or minus standard deviations of PSA/gamma-seminoprotein ratios for stages A, B, C and D prostate cancer were 1.847 +/- 0.786 (11 patients), 2.740 +/- 1.536 (30), 7.626 +/- 9.140 (12) and 27.149 +/- 70.500 (34), respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Antigens, Neoplasm↗
PubMed1993

Phase II study of Tc-99m MAG3 in patients with nephrourologic diseases.

Tc-99m-labeled mercaptoacetyltriglycine (Tc-99m MAG3) is a recently introduced radioagent that is excreted by tubular function. The aim of this study was to test Tc-99m MAG3 as an imaging agent for renal scintigraphy and renal plasma flow measurement. Image quality was tested with four different administered doses of Tc-99m MAG3, 100 MBq, 200 MBq, 300 MBq and 400 MBq, in four patients each. All administered doses except 100 MBq were sufficient for visible inspection of the nephrogram and drainage images; however, an administered dose higher than 300 MBq was necessary to maintain the quality of the blood perfusion image. The blood clearance with Tc-99m MAG3 or I-131 orthoiodohippurate (I-131 OIH) was calculated within the same day by the single blood sampling method. The blood clearance with Tc-99m MAG3 was 1.2-fold lower than with I-131 OIH, but correlated well (OIH = 91.34 +/- 0.932 MAG3, r = 0.953, P < 0.001). The blood clearance with Tc-99m MAG3 also correlated with the percentage of renal uptake estimated by the count-based gamma camera method at 1.5 to 2.5 minutes after injection (ERPF = -59.13% +/- 16.87% uptake, r = 0.845, P < 0.01). The mean labeling yield of Tc-99m MAG3 was 97%. None of the patients complained of side effects from Tc-99m MAG3. Tc-99m MAG3 is concluded to have good properties as a tubular radioagent for dynamic renal scintigraphy and renal plasma flow measurement.

Female↗
PubMed1993

Clinical experience of assisted circulation with a centrifugal pump at Tokyo Women's Medical College.

In postpericardiotomy patients, the use of pulsatile pumps is limited in a semielective fashion to patients whose postoperative marginal hemodynamics are expected preoperatively. Since 1989, 25 patients have undergone assisted circulation with a centrifugal pump: 15 (60%) were weaned from the pump, and 7 (28%) survived. In 1988, we heparin-coated the Bio-Pump using the Carmeda technique and developed a totally heparin-coated left heart bypass system together with heparin-coated cannulas and tubing. Four postpericardiotomy patients underwent left heart bypass with this system without heparin for 2 to 9 days. No thrombus was detected in the system. Left heart bypass with a centrifugal pump has been used as a supportive method in surgical repair of thoracic or thoracoabdominal aortic aneurysm. To overcome intraoperative hypothermia and hypoxia, we used a small membrane oxygenator with a heat exchanger in 11 patients, and postoperative recovery dramatically improved. We also developed a preassembled percutaneous cardiopulmonary support (PCPS) system with an automatic priming function using Terumo's straight path centrifugal pump and small membrane oxygenator in cooperation with the Terumo Corporation. This system was used in a patient with cardiogenic shock after acute myocardial infarction. The setup and priming took only 5 min, and 2.5-3.5 L/min of flow was obtained.

Adult↗
PubMed1993

Can brain impairment be detected by in utero behavioural patterns?

Fetal behavioural patterns were examined to test whether they could be used to localise sites of brain damage antenatally. Decreased fetal movement, persistent nonreactive fetal heart rate (FHR) pattern, and/or central nervous system malformation were used as indicators of possible neurological impairment. Ten fetuses tested in this way underwent further ultrasound examination observing movement of the extremities, chest wall (breathing), and eye and mouth, and active/quiet FHR patterns. Eight of these 10 fetuses were found on postnatal examination to have a brain impairment. The fetuses having potential in utero brain impairment were divided into four groups: those with (1) lesion sites at, or caudal to, the pons-medulla that were specifically identified by fetal behaviour, (2) diffuse lesions in the brain which, although resulting in abnormal behaviour, could not be localised by this behaviour, (3) lesions localised in the cerebral hemisphere(s) but with no abnormal behaviour and (4) temporally abnormal behaviour in utero, finally changing over to a normal pattern with no neonatal neurological abnormality. A screening system for the antenatal assessment of brain impairment is thus proposed.

Brain Damage, Chronic↗
PubMed1993

Abnormal behavioral patterns in the human fetus at term: correlation with lesion sites in the central nervous system after birth.

We describe three fetuses at term that demonstrated abnormal behavioral patterns in utero when observed using real-time ultrasound. The abnormal patterns turned out to have neurologic correlations after birth. In case 1, despite a normal breathing pattern, no movement in any of the four extremities was observed, thus suggesting the existence of a spinal cord lesion at the rostral end, located at C4 or C5. In case 2 a lack of breathing movement was noted repeatedly, together with the abnormal finding that alternation of periods of rapid eye movement (REM) sleep with those of non-rapid eye movement (NREM) sleep was not present. These findings implied a lesion involving the pons and/or medulla oblongata. In case 3 movement of the four extremities, breathing movement, and alternating periods of REM sleep and NREM sleep were found to be within the normal range. The concurrence of regular mouthing and the NREM sleep period was not observed, however, suggesting impairment in the brain function responsible for NREM sleep located from the pons through the thalamocortical connection to the cerebral hemisphere.

Adult↗
PubMed1993

Prenatal evaluation and obstetrical management of fetuses at risk of developing lung hypoplasia.

The aim of this study was to measure the fetal lung area of normal human fetuses using ultrasound and them to test the predictive values of a nomogram in the identification of fetal lung hypoplasia. A nomogram for ultrasound-measured fetal lung area were constructed from 264 normal fetuses from 17 to 39 weeks of gestation. In 19 cases running the risk of developing lung hypoplasia, the sensitivity, specificity, and positive and negative predictive values of lung area measurements below the mean -2 SD were 75%, 100%, 94% and 100%, respectively, with total lung area showing a significant relation to the combined lung weight (Y = -1.05 + 2.06 X, r2 = 0.88). These results indicate that lung area measured by ultrasound is a good indicator of lung weight, and this nomogram of lung area may be useful in evaluating lung growth prenatally, as well as in the direct obstetrical management of fetuses at risk of developing lung hypoplasia.

Female↗
PubMed1993

Scanning electron microscopic studies of smooth muscle cells and their collagen fibrillar sheaths in empty, distended and contracted urinary bladders of the guinea pig.

This study was performed to clarify the structure of muscle cells and the arrangement of surrounding collagen fibrils in the guinea-pig urinary bladder by scanning electron microscopy with two different chemical-digestion methods. Morphological changes in the muscle cells and the collagen fibrils under stretching and contraction were also examined. The smooth muscle cells in the empty bladder were shaped like an unbranched stick 130 microns long. They elongated to 360 microns in the distended bladder, and 48 microns in the contracted bladder. These cells have short lateral processes touching the neighboring muscle cells in an end-to-side fashion. Longitudinal striations on the cell surface due to rows of caveolae and dense bands were recognizable irrespective of the extended or contracted conditions. Transversely arranged wrinkles, which were considered to be produced by surface enfolding during contraction, were marked on the surface of contracted muscle cells. Each muscle cell was accommodated by a thin lace-like sheath made of both separate and small-bundled collagen fibrils. That part of the fibrils in one sheath often extended to participate in another sheath suggested that the collagen sheaths not only modulate cell shape but also provide a structure serving the co-ordinated motion of neighboring muscle cells.

Animals↗
PubMed1993

[Expression of progesterone-binding protein in normal and neoplastic human adrenals].

Specific progesterone-binding protein (P4-BP) is demonstrated in adrenocortical nuclei of the guinea pig, but, not in nuclei of other animals. We tried to demonstrate the progesterone-binding activity in nuclei of human normal adrenals and adrenal tumors. Normal adrenals were obtained from six patients with renal cell carcinomas undergoing radical nephrectomy. Seven adrenocortical adenomas were obtained: five tumors from patients with Cushing's syndrome, one tumor from non-functioning adenoma, and one from aldosteronoma. Nuclei were purified from the tissues, and progesterone binding assay was performed. We could not demonstrated progesterone-binding activity in nuclei of six normal human adrenals. However, we demonstrated progesterone-binding activity in nuclei purified from human adrenocortical adenomas associated with Cushing's syndrome. Saturation analysis revealed a Kd of 13.85 +/- 1.99 nM (mean +/- SD, n = 5) and a binding capacity of 1.95 +/- 0.37 pmol/mg DNA (mean +/- SD, n = 5). A Kd of progesterone-binding activity in human adrenocortical adenoma was similar to that of guinea pig P4-BP, and a binding capacity was about one-fifteenth of guinea pig P4-BP. However, nuclei purified from a non-functioning adrenocortical adenoma and an aldosteronoma failed to demonstrate progesterone-binding activity. The binding activity was specific for progesterone. 5 alpha-pregnane-3,20-dione was a modest competitor, while 17 beta-estradiol, testosterone, cortisol, and other related steroids were poor competitors. Thus the progesterone-binding activity in human adrenals was similar to guinea pig P4-BP in the affinity and specificity of binding.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1993

[DNA ploidy of testicular germ cell tumors in childhood; difference from adult testicular tumors].

It is well known that there are various differences in the biological characteristics and clinical behavior between prepubertal testicular germ cell tumors and adult ones. We analyzed the nuclear DNA ploidy of testicular tumors in childhood using DNA flow cytometry for clarifying those biological features and shedding some insights in the pathogenesis of testicular germ cell tumors. Formalin-fixed, paraffin-embedded specimens of primary tumors taken from 9 boys with histological evidence of yolk sac tumors and 8 with prepubertal teratoma treated in our clinic were used for flow cytometry analysis with some modification of the Hedley's technique. The results were compared with those of adult testicular tumors which we previously reported. All specimens in children showed "DNA euploid"; DNA diploid in all teratomas and 6 yolk sac tumors, DNA tetraploid in other 3 yolk sac tumors. Neither distinct DNA aneuploidy nor DNA heterogeneity were detected in children. Our previous study proved that the vast majority of adult testicular tumors contain DNA aneuploid stemlines. Although prepubertal yolk sac tumor and teratoma are histologically identical with those in adults, this study apparently reveal the different DNA stemline ploidy in prepubertal testicular tumors compared with that in adult ones. It has been known that carcinoma in situ (CIS) of the testis is a precursor of adult testicular germ cell tumors and the CIS cells in precancerous state already shows aneuploid DNA histogram patterns. Moreover, CIS has never been observed in children. The current results are in agreement with the hypothesis that the pathogenesis of prepubertal testicular tumor is different from that of adult ones.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗