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Biomedical subjects

R Maruyama

Publications and source records attributed to R Maruyama.

At least 91 records · Page 5Linked to original sources
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↗
PubMed1988

Primary pulmonary amyloidosis with multiple nodules.

A 61-year old asymptomatic woman had a five-year history of pulmonary nodular lesions on routine radiographs. She underwent open lung biopsy, which revealed nodular lesions in the lungs and thickened pleura. Histological examination showed amyloid deposits in the pulmonary parenchyma and adjacent pleura. Congo Red staining of the specimen demonstrated green birefringence under polarized light. This affinity for Congo Red dye remained after potassium permanganate treatment, suggesting primary amyloidosis. Multiple nodular amyloidosis of the lungs should be included in the differential diagnosis of multiple pulmonary nodules.

Amyloidosis↗
PubMed1987

Differences in ventilatory responses to hypoxia and hypercapnia between normal and judo athletes with moderate obesity.

Hypercapnic and hypoxic ventilatory sensitivities were compared in twenty-one judoists and 24 control subjects with similar degrees of moderate obesity. Data from ten non-obese control subjects were also included as a reference. Mean body weight (BW) and % of ideal body weight in the judoists and the obese and non-obese controls were 100 +/- 14.8, 94.4 +/- 5.3 and 63.4 +/- 6.1 (mean +/- SD) kg, and 142.3 +/- 16.7, 142.2 +/- 12.9 and 98.4 +/- 10.7%, respectively. Mean body fat in the judoists was 16.2 +/- 13.9%, being 25.3 +/- 7.7% in the obese control group, the difference being significant (p less than 0.01). Hypercapnic sensitivities in terms of the CO2 ventilatory response slope (S) and its normalized value for 70 kg BW (SN) of the obese controls were higher than the judoists. These findings were also verified by the CO2-occlusion pressure responses. S and SN in the obese controls were significantly correlated with BW and % body fat. However, no positive correlation was found between BW and S or SN in the judoists as well as between lean body mass and S or SN in the obese control. Hypoxic sensitivity in terms of the PETO2-ventilation hyperbola slope (A) and its normalized value (AN) in the obese control was significantly higher than the non-obese control, but the difference from the judoists was not significant. A and AN were found to increase with increasing % body fat in both judoists and obese controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1987

Comparison of two synthetic progesterones on ventilation in normal males: CMA vs. MPA.

We administered chlormadinone acetate (CMA), medroxyprogesterone acetate (MPA), and placebo to 16 normal male subjects using a randomized double-blind crossover study. After CMA administration, minute alveolar ventilation increased by +1.04 +/- 0.22 (SE) 1/min (P less than 0.05) accompanied by decrements of arterial PCO2 (-4.0 +/- 1.0 Torr) (P less than 0.01) and [HCO3-] (-2.1 +/- 0.05 mM/l) (P less than 0.01). On the other hand, in the MPA runs the corresponding changes of the above parameters were +0.71 +/- 0.21 l/min (P less than 0.05), -2.9 +/- 0.6 Torr (P less than 0.01), and -1.3 +/- 0.3 mM/l (P less than 0.01), respectively. The slopes of hypoxic ventilatory and occlusion pressure response lines remained unchanged in hypocapnia after CMA or MPA ingestion, but they increased when entidal PCO2 was adjusted to the predrug level. The hypercapnic ventilatory and occlusion pressure response lines merely shifted to the left without changing their slopes with these agents. No significant differences in all the above parameters were found between CMA and MPA runs. We concluded that in the normal males the effect of CMA on ventilation was similar to that of MPA, despite the fact that the luteinizing activity of CMA was reported to be approximately 10 times higher than the latter.

Adolescent↗
PubMed1986

Hypercapnic and hypoxic ventilatory responses during growth.

Cross-sectional studies on hypercapnic and hypoxic ventilatory chemosensitivities were performed in 71 children ranging in age from 7 to 18 yrs. The subjects were classified into 6 successive 2-year age groups. CO2 ventilatory response was measured by rebreathing 5% CO2 in O2, a slight modification of the method originally proposed by Read. The results were evaluated when the CO2-ventilation feedback control system was supposed to have attained the open-loop condition. Hypoxic ventilatory response was measured by the isocapnic progressive hypoxia test. To obtain good reproducibility in the ventilatory response, end-tidal PCO2 was maintained at 5 mmHg higher than the resting condition throughout the test. Normalized ventilatory responses to CO2 by body surface area (S/BSA) progressively decreased from the 7-8 through the 11-12 yr groups, and then tended to decrease further in a more gradual manner with increasing age. This trend was very similar to the normalized CO2 output (VCO2/BSA), but did not parallel so closely the normalized O2 intake (VO2/BSA). When ventilatory and metabolic parameters were normalized by body weight (BW), or the lean body mass (LBM), qualitatively similar relationships between CO2 sensitivities and metabolic parameters were also obtained. Contrary to the hypercapnic response, hypoxic ventilatory chemosensitivities were not significantly different among the 6 different age groups. We concluded that normalized hypercapnic chemosensitivity decreased during growth and corresponded well with decreased CO2 output per unit body mass.

Adolescent↗