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Biomedical subjects

R Maruyama

Publications and source records attributed to R Maruyama.

At least 19 recordsLinked to original sources
PubMed1992

Cerebral myxopapillary ependymoma.

A rare case of myxopapillary ependymoma is reported. The tumor occurred in the cerebral hemisphere of an 8-year-old girl and had no relationship to the lateral ventricles. Microscopically, it showed abundant mucin production around papillary or reticular structures. Immunohistochemically, these tumor cells were weakly positive, with glial fibrillary acidic protein demonstrated in part of the tumor and vimentin strongly demonstrated throughout the tumor. The results may indicate the poorly differentiated nature of this tumor. This is the second reported case of intracranial myxopapillary ependymoma.

Brain Neoplasms↗
PubMed1992

Dependence of biphasic heart rate response to sustained hypoxia on magnitude of ventilation in man.

We studied the dynamic profile of respiratory and circulatory activities during sustained isocapnic hypoxia in healthy males. In response to end-tidal PO2 depression to about 55 Torr, minute ventilation first increased briskly and then depressed. Such biphasic response to hypoxia was also observed in the heart rate. A significantly positive correlation was found between the magnitudes of ventilatory and heart rate responses. No significant increases were found in arterial noradrenaline and potassium, but adrenaline significantly increased gradually with time. Furthermore, when VT and f were intentionally maintained constant so as to prevent the biphasic ventilatory change, the biphasic heart rate response previously seen in spontaneous hypoxic breathing disappeared. We suggest that the heart rate is mainly determined by the pulmonary vagal inflation reflex. Putative neurochemicals to elicit hypoxic ventilatory depression, and arterial catecholamine and potassium concentrations may not be directly related to the specific profile of the biphasic heart rate response during moderate hypoxia.

Adult↗
PubMed1991

Tinea corporis due to Microsporum canis from an asymptomatic dog.

The patient was a 19-year-old female student who purchased a puppy from a pet shop four weeks earlier. At the time of her first examination, an annular edematous erythema with adherent scales and vesicles surrounding its margin was seen on the left forearm. On direct examination of the vesicles, fungal elements were detected, and Microsporum canis was isolated. The puppy was a Pomeranian and was kept in the house at all times. No clinical lesions were seen on the puppy, and the Wood's lamp test was negative. However, M. canis was isolated from the animal by the hairbrush method. Symptoms disappeared after the patient was treated topically with terbinafine cream for three weeks. Although the dog received no treatment whatsoever, there was no evidence of the disease on the pet. Results of the hairbrush method performed on the pet two and three weeks later were negative, but, at five weeks, it was again positive. Human infection with M. canis from an asymptomatic dog was demonstrated in this case. Attention should be paid to preventing infections from animals without lesions.

Adult↗
PubMed1991

Dynamic profile of cardiovascular activity in relation to augmented ventilation and humoral agents during hypercapnic hypoxia.

A time course of cardiovascular activity in 8 healthy males in relation to augmented ventilatory activity and humoral factors was observed during step CO2 elevation with constant hypoxia. During the first step increase, by 3 Torr in end-tidal PCO2 (PETCO2), the heart rate (HR) initially tended to decrease, then slowly increased to slightly below that of the previous eucapnic level, whereas ventilation maintained a gradual rise throughout this period. On the other hand, during second step PETCO2 elevation, by a further 3 Torr, both HR and ventilation progressively increased. The plasma catecholamine (CA) concentration was also significantly elevated during this period, suggesting a concomitant enhancement in sympathetic activity. Blood pressure (Bp) was progressively augmented throughout the entire hypoxic challenge. We conclude that 1) the characteristic profile of HR change may be explained by the observation that initial HR depression by peripheral chemoreceptor stimulation is gradually overridden by delayed hyperventilation, CA elevation, and enhanced sympathetic activity; 2) Bp augmentation may be elicited by increased CA release and sympathetic activity; and 3) plasma K+ concentration does not change so as to affect cardiovascular and respiratory activity.

Adult↗
PubMed1990

Boar transition protein 2 and 4 isolated from late spermatid nuclei by high-performance liquid chromatography.

The boar late spermatid nuclei retaining transition proteins (TPs) could be obtained from the testis by the use of antipain to inhibit TP-degrading proteinases of the nuclei. The enzymes detected in acid extract including the basic proteins were inactivated by reduction and carboxymethylation of the proteins. The reduced and carboxymethylated basic proteins were fractionated by differential precipitation between 3% trichloroacetic acid (TCA) and 3-20% TCA. From the 3% TCA-precipitate, boar TP2 and TP4 were isolated by high-performance liquid chromatography (HPLC) on Nucleosil 300 7C18. The two TPs were characterized by acid urea- and SDS-polyacrylamide gel electrophoreses and amino acid analysis. Boar TP2 closely resembled rat and mouse TP2s, and ram protein 3 in its high content of serine and basic amino acids, the presence of cysteine and molecular weight. Boar TP4 was similar to ram protein P1 in its high content of basic amino acids, the presence of cysteine and molecular weight. But the TP2 and TP4 differed in electrophoretic mobility on acid urea-gel and solubility in 3% TCA from those of the other species. The HPLC used here also enabled us to efficiently separate boar TP1, TP2, TP3 and TP4, and to estimate that the amount of the TP2, TP3 and TP4 was about 1/8, 1/4 and 1/4 that of the TP1, respectively.

Amino Acids↗
PubMed1990

Prognostic significance of alpha-1-antitrypsin in early stage of colorectal carcinomas.

We have previously shown that human colorectal carcinoma cell lines, RCM-1 and CoCM-1, synthesize alpha-1-antitrypsin (alpha 1-AT) in culture. We have studied immunohistochemically the incidence of alpha 1-AT on histologic sections from paraffin-embedded tissues of surgically resected colorectal carcinomas and their metastatic foci, polypectomized adenomas, and normal mucosae. alpha 1-AT was detected in 89 (61%) of 145 carcinomas (including 14 carcinomas in adenoma), and 12 (39%) of 31 adenomas. But only 2 (4%) of 55 normal colorectal mucosae were positive for alpha 1-AT. In metastatic tumor cells of colorectal carcinomas in lymph nodes and other organs, alpha 1-AT positivity was 60% and 82%, respectively. The incidence of alpha 1-AT was markedly higher in advanced adenocarcinomas than in early ones and more frequent in adenocarcinomas of right side (including transverse colon) than those of left side and rectum, regardless of their histological malignancy grades. In mucinous carcinomas the frequency was greater (8 of 9 cases) than in conventional adenocarcinomas. Clinical follow-up of the patients with colorectal carcinomas suggested that alpha 1-AT positivity in Dukes' stage A/B tends to correlate with unfavorable prognosis irrespective of the grade of histologic differentiation of carcinoma, but there is no significant relation in Dukes' stage C/D. Our findings suggest that alpha 1-AT in colorectal carcinoma is related to the invasive and metastatic capacity. It may thus serve as a biologic marker for prognosis of colorectal carcinomas at relatively early stages (Dukes' stage A/B).

Adenoma↗
PubMed1990

Lymphatic invasion of nevus cells observed in intradermal nevus.

A pigmented nevus was observed on the medial aspect of the left scapula of a 30-year-old woman. Histologically, the lesion showed the pattern of a typical intradermal nevus, consisting of type A, B and C cells. However, the most characteristic feature of this intradermal nevus was the projection of polypoid masses of nevus cells containing melanin into the lumen of a lymphatic vessel in the upper dermis. To our knowledge, lymphatic invasion in pigmented nevi is rare; this finding is interesting, if we consider the relationship between nevus cells and lymph nodes.

Adult↗
PubMed1990

Infundibular keratosis--report of two cases.

Two cases of infundibular keratosis are presented, characterized histopathologically by funnel-shaped, invaginating, epithelial lobules showing infundibular keratinization and connection with pilosebaceous structures. Lightly-staining, glycogen-laden epithelial cells predominated within the two tumors. Differential diagnoses with other infundibular tumors and relationships to trichilemmoma are discussed.

Aged↗
PubMed1989

Hepatic carcinosarcoma demonstrated by Ga-67 scintigraphy.

A case of a primary hepatic carcinosarcoma, a very uncommon liver tumor in adults, demonstrated by Ga-67 scintigraphy, was reported. The liver image showed a lesion of low activity in the left lobe of the liver, whereas the Ga-67 image showed a moderate accumulation in the lesion detected by the liver scan and further indicated a high accumulation extending downwards from the hepatic lesion. An autopsy revealed that the huge abdominal tumor was composed of hepatocellular carcinoma and malignant mesenchymoma in the left hepatic lobe and in the lower part of the tumor, respectively. The Ga-67 image demonstrated these two different histological components of the tumor.

Carcinosarcoma↗
PubMed1989

Afferent and cardiodynamic drives in the early phase of exercise hyperpnea in humans.

The ventilatory and cardiac responses to voluntary and passive exercise were studied in 20 healthy subjects. These responses to passive leg exercise were also studied in 23 patients with spinal cord transection at the level of T5-T12. In the normal subjects, minute ventilation (VE) increased abruptly from the first breath after the onset of the two types of exercise. In contrast, cardiac output (Q) increased gradually in voluntary exercise, exhibiting significant augmentation from the fifth breath. Q changed insignificantly in passive exercise. In the patients with spinal cord transection, neither VE nor Q changed with passive exercise. These results suggest that ventilatory responses at the onset of mild exercise are related to drives from the moving limbs. We could not detect any evidence to support cardiodynamic hyperpnea at the onset of exercise.

Adolescent↗
PubMed1989

Differential sensitivity to hypoxic inhibition of respiratory processes in the anesthetized rat.

To estimate the sensitivity to hypoxic inhibition of various regulatory processes for respiration, changes in breathing pattern during hypoxic ventilatory depression (HVD) were analyzed in the halothane-anesthetized spontaneously breathing rat using a "progressive isocapnic hypoxia test." In the carotid sinus nerve (CSN) intact rats, ventilatory augmentation was followed by depression due to reduction in respiratory frequency (f) at end-tidal PO2 (PETO2) levels below 50-60 mmHg despite increased afferent activities from the carotid chemoreceptors. After CSN section, ventilation was progressively depressed at PETO2 lower than normoxic level with simultaneous decreases of f and tidal volume. An increase in CO2 stimulus or the prevention of arterial hypotension during hypoxia by infusing a vasoconstrictor agent (phenylephrine) inhibited the occurrence of ventilatory depression in both the CSN intact and denervated animals. In all cases studied, the reduction in f resulted mainly from the prolongation of expiratory time (TE). The results suggest that in the anesthetized rat the effect of respiratory stimulation from carotid chemoreceptor afferents becomes inadequate to offset the prolongation of TE due to the central hypoxia at lower PETO2, and that the neural process for regulating TE is the major site of deterioration during central hypoxic inhibition. Roles of CO2 stimulus and systemic circulatory conditions in the generation of HVD were also discussed.

Afferent Pathways↗
PubMed1989

Neutral proteinases and inhibitors secreted by human rectal adenocarcinoma cell line (RCM-1).

A human rectal adenocarcinoma cell line, RCM-1, secreted some neutral proteinases: metallo-, serine and cysteine proteinases; and trypsin inhibitors into the serum-free conditioned medium (SFCM) in vitro. They were separated by anion-exchange and gel filtration high-performance liquid chromatography. SFCM from the cells of early passage numbers (20-24) contained native activities of serine proteinase and collagenolytic metalloproteinase. However, after several passages the native activities of them were diminished and latent form of metalloproteinase increased. In contrast to the native proteolytic activities, trypsin inhibitory activity was elevated in SFCM from the cells of passages 38-42. It inhibited the serine proteinase secreted by the same cells of early passage numbers. Furthermore, the serine proteinase was able to activate the latent form of metalloproteinase. Cooperative roles of these tumor-secreted proteinases and inhibitors may be important in tumor invasion.

Adenocarcinoma↗
PubMed1988

Increased ventilatory response to acute hypoxia with high Hb-O2 affinity induced by Na-cyanate treatment in the rat.

The effects on the ventilatory response to acute hypoxia of increasing the Hb-O2 affinity by NaOCN administration were studied in the halothane anesthetized spontaneously breathing rat. Increases in ventilation during the progressive hypoxia test were significantly augmented, and ventilatory depression occurring in severe hypoxia was clearly inhibited in the NaOCN-treated rat. Beneficial effects of NaOCN treatment probably result from the protection of respiratory regulating mechanism from functional deterioration in severe hypoxia.

Animals↗
PubMed1988

Relationships among panic-fear personality, aging, and ventilatory activity.

We have studied 204 healthy male subjects ranging in age from 20 to 59 years. They were divided into four 10-year age groups. Each age group was further divided into 2 subgroups with high and low Panic-Fear scores. The ventilatory activities of all the groups were compared. In the younger generation (20-39 years), the low PF group revealed a higher slope in CO2 response curve than the high PF group (p less than 0.05). This result was considered to be related to the difference in CO2 production between the two groups. In the older age groups, however, the high PF subjects exhibited a tendency to increase the CO2 response slope with increasing ages. This contradictory result was thought to be due to the age dependent change in biogenic amine activity.

Adult↗
PubMed1988

Comparison of ventilatory response between dead space and CO2 breathing in humans.

Ventilatory response during external dead space (tube) breathing and CO2 inhalation for given increase in PETCO2 were compared at different levels of PETO2 (hyperoxia, normoxia, and hypoxia) in human subjects. At all the PETO2 levels studied, magnitude of increment in minute ventilation (VE) and tidal volume were larger in the dead space breathing than in the CO2 inhalation. The slope of CO2-ventilation response line was significantly steeper in the dead space breathing only in the hypoxic condition. There was no significant difference in frequency response to CO2 between the two methods. These results suggested that augmented ventilatory response to CO2 in the dead space breathing occurs in the condition of peripheral chemoreceptor activation.

Administration, Inhalation↗
PubMed1988

High-molecular-weight neutral proteinase of rat ascites hepatoma cells and their collagenolytic activity.

A high-molecular-weight proteinase in rat ascites hepatoma AH109A cells was purified to apparent homogeneity by conventional chromatographic techniques. The purified proteinase degraded over the broad pH range, 7.0-9.0, not only denatured hemoglobin but also type I and IV collagen in the absence of calcium. Its activity was maximum at pH 8.0, heat-labile and affected by thiol reagents. Serine proteinase inhibitors such as diisopropyl fluorophosphate, soybean trypsin inhibitor, leupeptin, and antipain also partially inhibited its activity. The enzyme was found mainly in the cytosol fraction, and had a molecular weight of 450 kilodaltons (Kd) as determined by gel filtration chromatography and showed a single band on polyacrylamide gel electrophoresis under nondenaturing condition, although it was dissociated into lower-molecular-weight subunits, 25.5-32 Kd in the presence of sodium dodecyl sulfate and 2-mercaptoethanol. These properties suggested that it was a kind of a cytosolic high-molecular-weight proteinase. The collagenolytic activity of this proteinase may play an important role in cancer cell invasion and metastasis.

Animals↗