Search PubMed⌕ Search

Biomedical subjects

S Fukuda

Publications and source records attributed to S Fukuda.

At least 685 records · Page 38Linked to original sources
PubMed1987

Exstrophy of the cloacal membrane. A pathologic study of four cases.

Exstrophy of the cloaca is a rare congenital anomaly. The authors add the pathologic findings of four distinct cases reported in this article to those reported in the literature. In all cases, common anomalies were recognized. In addition, there were rare anomalies, such as single umbilical artery, vestige of the left superior vena cava, common mesenterium, calcification of the cerebellum, incomplete segmentation of the left lung, abnormal shape of the liver, and knock-knee. The embryology of this complex anomaly is difficult. It is considered that this anomalous condition results from breakdown and mesodermal invasion of the cloacal membrane.

Abnormalities, Multiple↗
PubMed1986

Extraneuronal serotonin accumulation in peripheral arteries of the rat.

Accumulations of serotonin (5-HT) and norepinephrine (NE) were compared in control and 6-hydroxydopamine (6-OHDA) pretreated rat aorta, mesenteric and tail arteries. The distribution of these amines was corrected by subtracting tissue uptake of tritiated sorbitol in the extracellular space. 5-HT greatly accumulated both in control and 6-OHDA pretreated arteries. In contrast, NE accumulation in mesenteric and tail arteries was substantially decreased after 6-OHDA treatment. In the aorta 6-OHDA pretreatment did not affect the accumulation of both amines. These findings suggest that 5-HT accumulation in these arteries is mainly extraneuronal, and NE mainly neuronal. Since the accumulation of 5-HT in the aorta was not influenced by pretreatment with 10 microM NE, the extraneuronal uptake mechanisms for 5-HT and NE appear to be different.

Animals↗
PubMed1986

Acetylated low-density lipoprotein is endocytosed through coated pits by rat peritoneal macrophages.

The surface distribution of the scavenger receptors for acetylated low-density lipoprotein (acetyl-LDL) and their endocytic behavior were studied by the direct immunoperoxidase method using monomeric conjugates of horseradish peroxidase with Fab' antibody raised against LDL. The receptors were demonstrated to be distributed diffusely on the surface membrane of cultured peritoneal macrophages, with preferential localization in coated pit regions. With temperature shift from 4 degrees C to 37 degrees C, acetyl-LDL bound to the surface membrane rapidly disappeared, but became detectable in coated vesicles or lysosomes. Further incubation in the presence of acetyl-LDL revealed lipid vacuoles devoid of a limiting membrane in the cytoplasm, transforming macrophages into typical foam cells. These data suggest that the binding of acetyl-LDL to its receptors triggers the clustering of the receptors into the coated pit regions through which acetyl-LDL is endocytosed by coated vesicles to be degraded in lysosomes with subsequent intracellular accumulation of cholesterol esters.

Animals↗
PubMed1986

Hypoxic-ischemic brain lesions found in asphyxiating neonates.

Early hypoxic-ischemic brain lesions were examined regarding 26 autopsy cases which had severe asphyxia at birth and died within the first week. All cases were divided into three groups according to the birth weight: group A of less than 1,000 grams, group B of 1,001-2,500 grams, and group C of more than 2,501 grams. Neocortical and deep gray matter revealed pyknotic and karyorrhectic neuronal changes; however, in group A, these changes tended to be obscure. The hippocampus was the predictive site of the neuronal changes such as pyknotic neurons in Sommer's sector and karyorrhectic neurons in subiculum. In 12 cases, pontosubicular-type necrosis was found. White matter lesions were relatively characteristic and there was an early appearance of pathological astrocytes such as gemistocytic, Alzheimer-type 2 and stellate astrocytes, periventricular leukomalacia with or without hemorrhage. The brain stem and cerebellar lesions were also found occasionally revealing neuronal or glial changes. We applied the immunoperoxidase method using antisera to glial fibrillary acidic protein (GFAP) and S-100 protein for determination of pathological astrocytes. GFAP was a useful marker for pathological astrocytes in the subpial region and in the white matter. S-100 protein was present in Bergmann's glia and satellite glia as well as pathological astrocytes.

Asphyxia Neonatorum↗
PubMed1986

Cystic brain lesion in utero.

Two autopsy cases of cystic brain lesion in utero are reported. One of them was a donor infant of twin transfusion syndrome. The baby died immediately after birth and showed multicystic encephalomalacia in the distribution of the anterior cerebral artery. The second baby was a stillborn infant with thanatophoric dwarfism with associated chronic periventricular leukomalacia (PVL). It was suggested that the multicystic encephalomalacia and chronic PVL found in the first and second cases were caused by persistent circulatory disturbances in utero.

Cysts↗
PubMed1986

Estimation of exercise capacity from oxygen consumption in the recovery phase of submaximal exercise.

We analyzed the transient response of oxygen consumption (VO2) after the sudden termination of exercise. The study population consisted of 20 male athletes (age 13 to 15.9 years) and 87 male patients, 59 of whom (age 4.8 to 17.8 years) were considered to be normal subjects, and 28 of whom (age 6 to 14.8 years) had restricted physical activity because of underlying heart diseases (restricted group). The exercise tests were performed according to Bruce's protocol and terminated at signs of exhaustion. As soon as exercise ceased, the examinee sat on a chair and took rested completely. VO2 was measured every 30 seconds throughout the test. We characterized the rate of the initial decay of the VO2 transient as the ratio of the 30 second VO2 right after the exercise to that at the end of the exercise (Irv). This index did not differ significantly among the groups. On the other hand, Exc, the Irv normalized by the end-exercise VO2, was a sensitive index for separating the restricted group from the control and athlete groups. Should the Exc remain sensitive enough to quantify exercise capacity regardless of the intensity of the exercise imposed, even the submaximal exercise test should enable us to safely evaluate the exercise capacity of patients with impaired cardiac function.

Adolescent↗
PubMed1986

Investigation of regional differences in water and electrolyte absorption across the human colon by in vivo perfusion method.

Colonic perfusion studies were performed to evaluate regional differences in water and electrolyte absorption across the human colon. In 19 healthy male volunteers, a 5-lumen tube with two balloons was inserted into the colon by the endoscopic retrograde bowel insertion (ERBI) method and a 25 cm segment of either the right or the left colon was perfused with an isotonic electrolyte solution simulating the fasting ileal content at a rate of 5 ml/min. Additionally into 5 subjects of the right colon and 5 subjects of the left colon, PSP solution was injected and mean transit time was calculated by the dilution method. Higher absorption rates of water, Na and Cl were observed in the right than in the left colon. Mean transit time was longer in the left than in the right colon. It was considered that the right colon had greater absorptive capacity than the left. The colonic perfusion study by the use of ERBI method made it possible to determine the absorption of water and electrolytes in the right and left colon directly in man, and would be useful to elucidate the pathophysiology of colonic diarrhea.

Adolescent↗
PubMed1986

Bilateral cystic nephroblastomas and botryoid sarcoma in a child with Dandy-Walker syndrome.

We report an autopsy case of an 8-month-old male infant with bilateral cystic nephroblastomas, a botryoid sarcoma involving the urinary bladder, microencephaly, the Dandy-Walker syndrome, bilateral cataracts, hypospadias, and male pseudohermaphroditism. An unusual combination of congenital malformation and tumors may reflect the presence of a mutant gene.

Dandy-Walker Syndrome↗
PubMed1986

[Experimental viral labyrinthitis--an immunohistochemical investigation of the cochlear lesion].

Pathogenesis of viral labyrinthitis is still poorly understood despite the dimension of clinical problem. This study was undertaken in order to elucidate the pathogenesis of viral labyrinthitis by the immunohistochemical investigations of infected cochleas. HVJ (Sendai virus) and mumps virus have been used to create an animal model of viral labyrinthitis. The cochleas of adult guinea pigs with intralabyrinthine inoculation of virus through the round window membrane and with intravascular injection of virus were investigated by histopathological and immunohistochemical techniques (immunofluorescent and Avidin-Biotin-Peroxidase Complex method). Control animal received only the culture medium. Histopathologically, fibrosis of scala tympani, vacuolization of stria vascularis, cell infiltration in perilymph were observed in the animals with intralabyrinthine inoculation, whereas no significant changes were observed in those with intravascular injection. Immunohistochemical studies revealed that viral antigen of HVJ was found in stria vascularis (6/11), Reissner's membrane (5/11), Organ of Corti (2/11) and viral antigen of mumps was found in stria vascularis (3/11), Reissner's membrane (1/11), Organ of Corti (1/11) in inoculated side of cochlea. In animal with intravascular injection, viral antigen of HVJ was found in stria vascularis (4/6), Organ of Corti (1/6) and viral antigen of mumps was found in stria vascularis (5/18), Organ of Corti (2/18). Cochleas of control animal showed no evidence of viral antigen. Viral antigen of both viruses were found in stria vascularis, Reissner's membrane, and Organ of Corti. Of these, Stria vascularis showed stronger affinity to these viruses. The results of intravascular injection indicate that endolymphatic labyrinthitis may ensure as a result of viremia.

Animals↗
PubMed1986

Mechanisms of extraneuronal serotonin uptake in the rat aorta.

The mechanisms of extraneuronal serotonin (5-HT) uptake in the rat aorta were studied. Aortic strips were pretreated with 0.1 mM pargyline and incubated with 0.1 to 9.1 microM 5-HT (5-HT, 0.02-1.60 microgram/ml including [3H]-5-HT, 0.02 microgram/ml) for 1, 2, 3 and 5 min at 37 degrees C. Accumulation of [3H]sorbitol was used to correct for extracellular distribution of this amine. The initial rate of 5-HT uptake was related linearly to the substrate concentration within the tested range. Cocaine, imipramine, desipramine (10 microM each), Na+-free solution and cooling (0 degrees C) inhibited markedly both the 1- and 5-min uptake of 5-HT. Removal of the endothelium did not affect the 5-HT uptake for 1 min but reduced slightly that for 5 min. Corticosterone (10 microM), norepinephrine (10 microM) and 6-hydroxydopamine pretreatment did not affect the uptake of 5-HT. Autoradiography demonstrated that uptake of 5-HT for 5 min in the rat aorta occurs primarily at the smooth muscle cells near the lumen. These results suggest that the rat aorta has a large capacity of cocaine-sensitive extraneuronal uptake of 5-HT. This uptake appears to occur primarily in the muscle layers adjacent to the lumen, suggesting that the muscle cells of the luminal side function differently from those from the adventitial side. The mechanism of the extraneuronal uptake of 5-HT appears to be different from that of norepinephrine and the extraneuronal uptake of 5-HT occurs initially in a nonsaturable mode and later through a Na-dependent, carrier-mediated transport.

Animals↗