Biomedical subjects

Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 595 records · Page 33Linked to original sources

PubMed1990

Total and local impedances of the chest wall up to 10 Hz.

To understand how bical mechanical chest wall (CW) properties are related to those of the CW as a whole, we measured esophageal and gastric pressures, CW volume changes (measured with a head-out body plethysmograph), and anteroposterior and transverse CW diameter changes (measured with magnetometers attached to the surface) during sinusoidal forcing at the mouth (2.5% vital capacity, 0.5-10 Hz) in four healthy subjects. Total CW resistance decreased sharply as frequency rose to 3-4 Hz and remained relatively constant at higher frequencies. Total CW reactance became less negative with increasing frequency but showed no tendency to change sign. Above 2 Hz, diameters measured at different locations changed asynchronously between and within the rib cage and abdomen. "Local pathway impedances" (ratios of esophageal or gastric pressure to a rate of diameter change) showed frequency dependence similar to that of the total CW less than 3 Hz. Local pathway impedances increased during contraction of respiratory muscles acting on the pathway. We conclude that 1) total CW behavior is mainly a reflection of its individual local properties at less than or equal to 3 Hz, 2) local impedances within the rib cage or within the abdomen can change independently in some situations, and 3) asynchronies that develop within the CW during forcing greater than 3 Hz suggest that two compartments may be insufficient to describe CW properties from impedance measurements.

Abdominal Muscles↗

PubMed1990

Abdominal pressure transmission in humans during slow breathing maneuvers.

Pressure transmission within the abdomen was studied in four subjects standing and supine, breathing slowly and performing slow breathing maneuvers. Pressures were measured in the stomach and rectum with air-containing balloon-catheter systems Pga(air) and Prec and in the stomach with a water-filled catheter system Pga(liq). Changes in Pga(air), Pga(liq), and Prec were nearly in phase and linearly related. The changes in Pga(liq) and Prec were nearly equal in all maneuvers, whereas the changes in Pga(air) were systematically greater than those of Pga(liq) and Prec during quiet breathing and relaxation maneuvers in the upright position. During expulsive maneuvers in either posture the abdominal shape and stomach position were relatively constant, and the changes in Pga(air) were nearly equal to those of Pga(liq) and Prec. Discrepancies between changes in Pga(air) and the other pressures were consistent with presumed changes in the height of the gastric air bubble. We conclude that abdominal pressure in humans is essentially hydrostatic during quiet breathing and slow breathing maneuvers.

Abdomen↗

PubMed1990

Aging effect on oxygen consumption of respiratory muscles in humans.

The first purpose of the present study was to develop a new method to examine oxygen consumption of respiratory muscles (VO2resp) in human subjects. The apparatus consists of an expandable dead space and a respirometer. When the dead space was increased at a constant rate (approximately 100 ml/min), minute ventilation (VE) and VO2resp increased gradually. Because the logarithm of VO2 was found to be approximately linearly related to VE, we characterized this relationship by the slope (logVO2/VE) and the intercept at VE = 0 (VO2met) of the semilog regression line. The second purpose of this study was to examine the relationship between VO2resp and aging. Six anthropometric and spirometric factors (age, height, weight, vital capacity, forced expiratory volume in 1 s, and body surface area) were analyzed in 37 normal subjects by simple and stepwise multiple regression analyses. We found a significant increase in logVO2/VE and a significant decrease in VO2met with age. In conclusion, 1) the present method is convenient to use, and we are able to study VO2resp over a wide range of ventilation without voluntary effort, and 2) age per se is one of the factors accounting for the observed increase in VO2resp with age.

Adult↗

PubMed1990

[Study of scanner counter for POS terminal system from view point of posture when take-out goods].

Recently, an increasing number of supermarkets have been introducing the point of sales (POS) system. The scanner counter of this POS system makes repetitive operations including taking goods out of basket, letting them pass through the scanner for their bar codes and then putting them in the next basket. The basket is about 25.5 cm deep, and the counter must be high enough to satisfy two conditions that the base surface and the upper edge of the basket are not too low and not too high, respectively to take goods out of it. In the present study, repetitive operations of taking goods from 16 spots at their respective different heights 49.5, 57.5, 65.5 and 73.5 cm of four corners of the basket was made to measure the posture, heart rate (HR) and electromyograms (EMG) on four sites (right shoulder and loin , left loin and right femoris) of the operator and to examine the height of the counter. EMGs on the right loin , left loin and right femoris showed significant differences (P less than 0.05) in case of goods' position, operator side less than contralateral side and of counter's height, 73.5 less than 65.5 less than 57.5 less than 49.5 cm. EMG on the right shoulder showed significant differences (P less than 0.05) in case of the goods' position, operator side less than contralateral side and of the counter's height, 73.5 cm greater than another height on operator side.

Adult↗

PubMed1990

Uncomplicated acute diverticulitis of the cecum and ascending colon: sonographic findings in 18 patients.

To determine the sonographic features of uncomplicated acute diverticulitis of the cecum and ascending colon, the sonographic findings in 534 patients who presented with right lower quadrant pain were reviewed. Of these, 18 patients had uncomplicated acute diverticulitis of the cecum and ascending colon. The diagnosis was confirmed by surgery (one patient), clinical course (17 patients), CT (eight patients), or contrast enema (11 patients). On sonography, a round or oval focus of varying echogenicity, which protruded from a segmentally thickened colonic wall and was surrounded by a hyperechoic area, was seen in all 18 patients. These were hypoechoic foci (12 patients), hypoechoic foci with internal strong echoes (three patients), and echogenic shadowing foci with surrounding hypoechoic bands (three patients). Extraluminal gas (one patient) and thickening of lateroconal fascia (six patients) were seen also. Findings of enlarged appendix, frank abscess, and ascites were absent. All patients, including the one who had laparotomy, were successfully treated medically for diverticulitis. Of 515 patients without diverticulitis, in only one patient with acute appendicitis did sonography show a hypoechoic protruding focus. Our experience indicates that the major sonographic finding in patients with uncomplicated acute diverticulitis of the right colon is a hypoechoic round or oval focus protruding from a segmentally thickened colonic wall.

Acute Disease↗

PubMed1990

[A case of medullary sponge disease associated with horseshoe kidney].

A 60-year-old man visited our hospital with complaints of micturition pain and interruption of urinary stream. X-ray examinations were performed, showing no bladder and urethral stone. However, KUB revealed bilateral multiple renal stones. Excretory urography showed a horseshoe kidney and a concentration of the contrast medium in the ectatic tubules at the pyramidal apices. Calculi were also located in these ectatic tubules. Thus, we considered that this was a very rare case of medullary sponge disease associated with horseshoe kidney. So far there has been no case report of medullary sponge disease with horseshoe kidney in our country.

Cystitis↗

PubMed1990

Transcriptional regulation of 3-methylcholanthrene-inducible P-450 gene responsible for metabolic activation of aromatic carcinogenes.

We have investigated the transcriptional regulation of 3-methylcholanthrene (3MC)-inducible P-450c gene which is involved in the metabolic activation of polycyclic aromatic carcinogens. Reverse genetic study using the fusion gene composed of the 5' upstream sequence of P-450c gene and the structure gene for bacterial chloramphenicol acetyltransferase (CAT) and a cultured cell line of Hepa-1 cells localized two kinds of cis-acting regulatory DNA elements. One is designated XRE or xenobiotic responsive element which is responsible for the inducibility of the gene and is distributed 5 times in the region from -3.0 to -0.5 kb. The other is BTE or basal transcription element whose deletion reduces a low level of the constitutive CAT expression to a background level, and which is localized immediately upstream of the TATA sequence. Both kinds of regulatory elements are necessary for a high level of inducible expression. Gel mobility shift assay strongly suggests that the binding protein to the XRE is an Ah receptor with a specific affinity for 3MC or 2,3,7,8,tetrachlorodibenzo-p-dioxin (TCDD). Without inducer treatment, cryptic form of the binding protein occurs only in the cytoplasm of the Hepa-1 cells. Upon treatment with the inducer, the cryptic form of the binding protein exhibits binding activity to XRE and, at the same time, translocates to the nuclei. The BTE-binding protein is an ubiquitous nuclear factor and its cDNA cloning reveals the DNA-binding feature with zinc finger motifs.

Animals↗

PubMed1990

[Adrenal hemangioma: a case report].

We report a rare case of adrenal hemangioma incidentally discovered by computed tomography (CT) in a 75-year-old female, the hormonal examination showed within the normal range, and ultrasound-sonography, CT scan and angiography disclosed the mass to be a non-functioning adrenal tumor. The tumor was removed operatively and the pathological finding was adrenal hemangioma. Twenty reported cases found in the Japanese literature are reviewed.

Adrenal Gland Neoplasms↗

PubMed1990

[A case report of isolated congenital tricuspid regurgitation].

Reports of isolated congenital tricuspid regurgitation are very rare. A 20-year-old female with severe tricuspid regurgitation was reported. The patient was admitted to our hospital with complaints of easy fatigability and palpitation. Right ventriculogram showed severe tricuspid regurgitation. She was treated with tricuspid valve replacement with a 33 mm bioprosthetic valve. Seven surgical treated cases of isolated congenital tricuspid regurgitation including our case were collected from literature and reviewed.

Adult↗

PubMed1990

[A case of cardiomyoplasty with synchronous stimulated latissimus dorsi muscle].

In December, 1988, a 57-year-old man sustained an acute myocardial infarction. He suffered from progressive cardiac failure, despite bed rest and intensive medical treatment. Finally, he developed hepatic and renal failure. Subsequent angiographic studies revealed the total occluded LAD (Seg. 6) and a large LV aneurysm. In January 1989, a left ventricular aneurysmectomy and cardiomyoplasty using the latissimus dorsi muscle were performed successfully. Two years after the operation, he is alive and well.

Coronary Disease↗

PubMed1990

[Fractionation and radiation injury--clinical aspect].

The late effect of normal tissues in altered fractionation was analyzed with our experience and review in clinical trial. In hypofractionation late effect in normal tissues increased in frequency with increased dose per fraction. In the other hand, the optimal ERD or fractionations in MFD were found in larynx, lung and esophagus. The ERD and the frequency of severe late effect in clinical trial with accelerated or accelerated hyperfractionation tended to be less than those of hyperfractionation. However the tolerance ERD in brain and abdominal organ have not been able to determine due to short life span, combined modality and few clinical trial.

Brain Neoplasms↗

PubMed1990

Choriocarcinoma with brain metastasis: report on two cases with long-term survivals.

Choriocarcinoma is a potentially curable neoplasm. Although the presence of brain metastases worsens the ultimate prognosis, aggressive therapeutic intervention is sometimes justified for brain metastases of a potentially curable neoplasm. In the present clinical report, we present two cases of choriocarcinoma with brain metastasis manifesting neurological deterioration, and discuss treatment strategies. From the results of treatment, we conclude that surgical removal of the lesion, followed by chemotherapy combined with irradiation, should be the treatment of choice in patients with progressive neurological deterioration.

Adult↗

PubMed1990

[Intracavernous indurations after injuries to the external genital parts caused by a motorcycle tank].

We have experienced 2 cases of intracavernous induration after injuries to the external genital parts caused by a motorcycle tank. Case 1. A 28-year-old male was admitted to our department complaining of painless indurations of the penile radix. Cavernosography showed segmental filling defect in left corpus cavernosum. Because erectile disturbance was noted, resection of the induration was carried out. Microscopic section of the excised tissue showed only fibrosis. Case 2. A 20-year-old male visited our clinic with chief complaints of induration of the penile radix and erectile disturbance. Corpus cavernosography demonstrated filling defect in bilateral corpus cavernosum. We recommended the resection of the indurations, but the patient refused. A brief review on etiology and therapy of intracavernous fibrosis was made.

Accidents, Traffic↗

PubMed1990

[Therapeutic values of prostaglandin D2 in nude mice bearing human ovarian carcinoma].

In vitro and in vivo effects of prostaglandin D2 on human ovarian cancer growth were examined by using a cell line, designated HR, derived from ascites of patient with serous cystadenocarcinoma of the ovary. The HR cell proliferation in vitro was dose-dependently inhibited at prostaglandin D2 concentrations between 0.1 and 4.0 micrograms per ml. The results of a 51Cr-release assay seemed to indicate that the inhibition resulted from a direct cytotoxic effect exerted by prostaglandin D2. All DNA, RNA, and protein synthesis by the HR cells was also inhibited in a dose-dependent manner with 48 hr exposure to prostaglandin D2. When nude mice were inoculated with 5 X 10(5) HR cells, the 50% survival time in the untreated group was 52 days. The 50% survival time of nude mice treated with 12 mg (but not 4 mg) of prostaglandin D2 per kg was significantly prolonged to 67 days, in addition to a significant inhibition of the tumor growth. Adjuvant effects of prostaglandin D2 on cisplatin in relation to tumor growth were also studied. Combinations of 0.2 or 0.4 microgram cisplatin per ml and 0.05 or 0.1 microgram prostaglandin D2 per ml, which did not affect the HR cell proliferation alone, resulted in a significant inhibition of cell proliferation. In addition, the tumor take of HR cells by nude mice in groups treated with a combination of cisplatin and prostaglandin D2 was inhibited.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

[Cardiac tamponade as an initial manifestation of acute myeloblastic leukemia].

A 28-year-old man was admitted to our hospital because of cardiac tamponade and pleural effusion. Although his peripheral blood picture was normal, his pericardial fluid contained a lot of myeloblasts with Auer bodies and a diagnosis of acute myeloblastic leukemia (M2) was made from the finding of bone marrow smears. The pericarditis was successfully treated with instillation of mitoxantrone into the pericardial space after drainage. He responded well to the systemic chemotherapy and achieved a complete remission. Although 27 cases of leukemia complicated with cardiac tamponade have so far reported, only three cases gave normal findings of the peripheral blood on admission. Leukemic pericardial effusion with cardiac tamponade in very rare as an initial manifestation of AML. The efficacy and safety of pericardial infusion of mitoxantrone were demonstrated in this patient.

Adult↗

PubMed1989

Domains of the SFL1 protein of yeasts are homologous to Myc oncoproteins or yeast heat-shock transcription factor.

We identified a yeast suppressor gene for flocculation (SFL1), which complemented a newly isolated sfl1 mutant. This mutation causes asexual cell aggregation. SFL1 encodes a 767-amino acid protein which has two domains significantly homologous to Myc oncoproteins and the yeast heat shock transcription factor (HSTF). The Myc homologous region in SFL1 overlaps with the conserved region in a series of interesting proteins: MyoD1, Drosophila achaete-scute, twist, daughterless gene products and immunoglobulin enhancer-binding proteins. In addition, the N-terminal region of the SFL1 gene product shows extensive homology to the DNA-binding domain of HSTF. Mutational analysis of SFL1 demonstrates that it is required for normal cell-surface assembly in vegetative growth. We propose that the SFL1 gene product may be a transcription factor which is involved in regulation of the gene(s) related to yeast flocculation.

Amino Acid Sequence↗

PubMed1989

A human homologue of the yeast GST1 gene codes for a GTP-binding protein and is expressed in a proliferation-dependent manner in mammalian cells.

A human homologue (GST1-Hs) of the yeast GST1 gene that encodes a new GTP-binding protein essential for the G1-to-S phase transition of the cell cycle was cloned from the cDNA library of human KB cells. The GST1-Hs cDNA contained a 1497 bp open reading frame coding for a 499 amino acid protein with mol. wt 55,754 and with the amino acid sequence homologies of 52.3 and 37.8% to the GST1 protein and polypeptide chain elongation factor EF1 alpha respectively. The regions potentially responsible for GTP binding and GTP hydrolysis were conserved in the GST1-Hs protein as well. When expressed in yeast cell, the GST1-Hs gene could complement the ts phenotype of yeast gst1 mutant. GST1-Hs and its mouse homologue were expressed in human fibroblasts and in various mouse cell types respectively, at relatively low levels in their quiescent states, and the level of those expressions increased rapidly, prior to the onset of DNA replication and the total RNA synthesis, when human or mouse fibroblasts were progressed out of the growth-arrested state by the addition of serum. A possible role of GST1-Hs in mammalian cell growth is discussed.

Amino Acid Sequence↗

PubMed1989

Primary structure of the silk fibroin light chain determined by cDNA sequencing and peptide analysis.

A cDNA clone, pFL18, carrying a putative full-length fibroin light chain (L-chain) sequence was isolated and its nucleotide sequence was determined. This revealed the presence of an open reading frame corresponding to a polypeptide with 262 amino acid residues. The sequence was concluded to be that of the L-chain with its signal peptide because corresponding amino acid sequences for the seven tryptic and the four chymotryptic peptides from the purified L-chain were all included and an N-terminal region having typical properties of a signal peptide was present. The N terminus of the mature form of L-chain was identified as N-acetyl serine by analyzing the acyl-dansylhydrazide derived from the N-acyl-amino acid which had been released from the N-terminal blocked chymotryptic peptide by the acylamino acid-releasing enzyme. It was suggested that a signal peptide had cleaved between Pro18 and Ser19, yielding a mature L-chain polypeptide consisting of 244 amino acid residues. The molecular weight of the L-chain was calculated to be 25,800 including the N-acetyl group. The L-chain contained three Cys residues, two of which were suggested to form an intramolecular disulfide linkage, leaving the third one at the most C-terminal position and in a relatively hydrophilic region as the most probable site of disulfide linkage with the fibroin heavy chain.

Amidohydrolases↗