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Biomedical subjects

F Nakamura

Publications and source records attributed to F Nakamura.

At least 253 records · Page 14Linked to original sources
PubMed1981

Arthrogryposis multiplex congenita: an autopsy case of a fatal form.

A case of a severe and fatal form of arthrogryposis multiplex congenita with a full necropsy examination is presented in which the central nervous system and many muscles of the four extremities were examined histologically. The most striking feature was a great reduction in the muscular tissue of the limbs with a marked increase in the adipose tissue. The muscular changes were thought to be caused by neurogenic atrophy, and microscopy of the spinal cord revealed developmental abnormalities, including degenerative changes of the anterior horn cells. Neonatal and fatal cases of arthrogryposis multiplex congenita reported in the literature are briefly reviewed, and the characteristics of the present case and its relation to other congenital neuromuscular disorders are discussed.

Adipose Tissue↗
PubMed1981

Postmortem changes in the actin-myosin interaction of rabbit skeletal muscle.

Postmortem changes in the actin-myosin interaction were studied by determining the amount of thick and thin filaments dissociated by ATP. The amount of separated filaments was very small in myofibrils prepared from muscles in rigor, while it increased markedly during post-rigor storage of muscles. Electron microscopically, separated thick and thin filaments prepared from stored muscles were similar to freshly prepared ones and no signs of proteolytic degradation of either type of filament could be observed. A protein which was released from myofibrils (probably from Z discs) on Ca2+-treatment seemed to be most closely related to the post-rigor dissociation of thick filaments from thin filaments.

Actins↗
PubMed1981

Hexosaminidase C in brain affected by Tay-Sachs Disease.

Hexosaminidase (Hex) C could be detected in human brains by DEAE cellulose column chromatography, when N-acetyl-beta-D-glucosaminidase activity was determined at pH 5.5. In the chromatographic pattern, the peak of Hex C was always higher than that of Hex A in control prenatal brains and conversely lower in postnatal brains. Hex C was not detected in the brains obtained from two cases of Tay-Sachs disease. In addition, the content of Hex C in the brains of two other Tay-Sachs cases was lower than that of the control. The observation suggests that the absence or reduction of Hex C may have some relation with biochemical defects in Tay-Sachs disease, although Hex C does not share common subunit structures with Hex A and the role of Hex C with respect to GM2-ganglioside degradation remains unknown yet.

Brain↗
PubMed1981

Absence of antibodies against SV5, measles and herpes simplex in indoor colony-bred cynomolgus monkeys.

One hundred and eighty-one cynomolgus monkeys born and raised at Tsukuba Primate Center for Medical Science (TPC) were serologically examined for the presence of antibodies against simian virus 5, measles virus and herpes simplex virus. All of them were virtually free from infections with these viruses, whereas wild-originated breeders kept at TPC were highly positive for these antibodies. These results can be regarded as demonstrating that an indoor breeding system such as TPC's is useful and valuable for producing nonhuman primates of good quality being completely free from those viral infections.

Animals↗
PubMed1981

Serological survey for SV5, measles and herpes simplex infections in newly-imported cynomolgus monkeys.

On 592 cynomolgus monkeys of newly-imported 14 different groups, sero-epidemiological follow-up surveys of natural infections with SV5, measles (MV) and herpes simplex (HSV) were conducted both at the time of arrival and at the end of the 9-week quarantine period at Tsukuba Primate Center for Medical Science (TPC). At the time of arrival, the positive rate of antibodies against these viruses greatly varied with different countries of origin. As regards SV5, the positive rate ranged widely from 0 to 94.9% among different import-groups, being markedly low in the Philippine monkey groups. The positive rate of MV antibody was generally very high, varying from 11.1 to 78.2% in almost all import-groups except two groups from Indonesia in which no positive case was detected. Concerning HSV, every import-group had a very high positive rate though the average antibody titer was not so high. Generally, the positive rates of SV5 and MV markedly increased by the end of quarantine period. Especially, MV positive rate reached 100% in almost all of the import-groups. However, two Indonesian groups showed no increase of SV5 and MV positive rates during the quarantine period. No increase of SV5 positive rate was detected either with any of three Philippine groups. As for HSV, the positive rate remained unchanged or rather decreased during the quarantine period in almost all groups except two Indonesian groups having shown a significant increase.

Animals↗
PubMed1981

[Counterclockwise rotation of the heart: a correlative study with tomographic echocardiography].

On the long-axis view of tomographic echocardiography, the aorto-septal angle (AS angle) of cases with straight back syndrome was wide and was thought to be due to clockwise rotation of the heart rather than right ventricular enlargement. In the present study, the AS angle of 21 cases with counterclockwise rotation of the heart (CCW) was measured on the long-axis view. The counterclockwise rotation of the heart defined here as having a shift of the transitional zone to the right with a small septal q wave at V2 and/or V3 to V6 in the precordial leads. Every case of CCW was found to have an absence of main pulmonary artery shadow on posteroanterior projection of the chest X-ray film. The control groups consisted of 40 normal individuals and 14 cases of straight back syndrome. The AS angle of normals ranged from 120 degrees to 158 degrees with a mean of 142 degrees. The AS angle of the latter varied from 140 degrees to 165 degrees with a mean of 150 degrees. On the other hand, the 21 cases with CCW showed the AS angle from 80 degrees to 129 degrees with a mean of 102 degrees. Since every CCW showed dilatation and/or elongation of the thoracic aorta on their radiographs, the narrowed AS angle was probably due to rightward twist of left ventricular outflow tract with some posterior retraction of the aorta. This causes the rightward twist of upper portion of the septum and results in a shift of the transitional zone to the right with a small q wave at V2 and/or V3 to V6 in the precordial leads. When normally visible main pulmonary artery shadow disappears on the postero-anterior chest X-ray film, the CCW is indicated radiographically. The narrowing of the AS angles on the long-axis views of tomographic echocardiography also indicates the CCW and correlate with both electrocardiographic and radiographic findings of CCW. The cause of CCW has not been well delineated. In the previous paper, we have suggested that the left ventricular overloading has little influence in producing CCW. In the present study, the 21 cases with CCW did not show either the left ventricular hypertrophy or the dilatation on their echocardiograms further supporting our hypothesis.

Aged↗
PubMed1980

An altered hexosaminidase A in the liver affected by Hurler and Hunter syndromes.

Total hexosaminidase (Hex) in the liver obtained from Hurler and Hunter syndromes displayed about ten times higher activity than that in control liver and moreover, its thermostability was significantly increased. On DEAE cellulose column chromatography, Hex A in the liver of those patients was eluted at much higher salt concentration than that required for elution of Hex A from control liver. There was no difference in elution patterns of Sephadex G-200 and Concanavalin A-Sepharose column chromatographies between the altered Hex A and control Hex A. It appears that the glycosaminoglycans accumulating in the liver of those patients are partly bound to Hex A, and that this binding may cause some changes of its properties such as ionic charge and thermostability.

Adolescent↗
PubMed1979

Sphingomyelinase activities in cultured skin fibroblasts from patients with Niemann-Pick Disease.

Sphingomyelinase activity in cultured skin fibroblasts from a fetus affected with infantile-type Niemann-Pick disease was 0.5% of control activity; the activities in cells from two patients with adult-type disease (Cases 2 and 3) were 5.0% and 59.0%. Sphingomyelinase activiy was separated into three peaks (I-III) by isoelectric focusing. The isoelectric points were 4.5, 4.9, and 5.2 for peaks I, II, and III, respectively. The three peaks in the Case 2 cells were drastically reduced; only a very small peak could be distinguished (pI of 4.7). On the other hand, three peaks were observed in the Case 3 cells. Peak I had a pI of 4.4, peak II a pI of 4.7, and peak III a pI of 5.2. Peak I was found at near normal level, but both peaks II and III were markedly reduced. Sphingomyelinase in the peak I fraction obtained from isoelectric focusing in Case 3 cells was found to have the same Km value as that in control cells.

Adult↗
PubMed1978

Prenatal diagnosis of GM1-gangliosidosis: biochemical manifestations in fetal tissues.

A prenatal diagnosis of GM1-gangliosidosis was made in a pregnancy at risk, on the basis of a deficiency of beta-galactosidase activity demonstrated in cultured amniotic fluid cells. Biochemical analyses were performed in the aborted fetus. GM1-ganglioside beta-galactosidase activity was reduced to 1% of the control value in both the brain and liver of the affected fetus. Lamellar bodies suggestive of membranous cytoplasmic bodies were found in cells of basal ganglions, while the accumulation of GM1-ganglioside in the brain was not remarkable.

Amniotic Fluid↗
PubMed1978

Chronic Niemann-Pick disease with sphingomyelinase deficiency in two brothers with mental retardation.

Clinical, biochemical, and electron microscopic studies are presented in two brothers with Niemann-Pick disease. The clinical features include hepatosplenomegaly and mental retardation without any other neurological signs. Roentgenograms of the chest showed bilateral diffuse reticular infiltration. The amounts of sphingomyelin and cholesterol in liver were increased, and sphingomyelinase activities in both liver and skin fibroblasts were markedly reduced in Case 1. Numerous foam cells and myelin figures were observed in the liver, kidneys, bone marrow, and lymph nodes on electron microscopical examination. These cases were regarded as a variant of Niemann-Pick disease from our investigations as they have mental retardation as an exceptional symptom when they are diagnosed as type B.

Adolescent↗
PubMed1978

Changes in restricted human cellular DNA fragments containing globin gene sequences in thalassemias and related disorders.

Human cellular DNA fragments from cells of normal subjects and patients with thalassemia obtained by restriction enzyme digestion were analyzed for their globin gene content. The fragments were separated on agarose gels, transferred to nitrocellulose filters, hybridized to globin [(32)P]cDNA, and radioautographed. One to ten picograms of globin gene sequences were detectable. With EcoRI digestion, eight to nine cellular DNA fragments were found to contain globin genes. Three of these contained beta-like gene sequences assayed with beta globin cDNA probe. One beta-like fragment was absent in DNA from a homozygous subject for hemoglobin Lepore. Two of the three beta gene-containing fragments present in normal DNA were absent in DNA from a patient with hereditary persistence of fetal hemoglobin. The same two fragments containing beta-like genes were absent from deltabeta thalassemic DNA and one new fragment containing beta-like genes was found. Together with results obtained by hybridization of these DNAs in solution, the data are consistent with deletion of specific restriction human DNA fragments in subjects with these disorders and a greater deletion of beta-like gene sequences in subjects with hereditary persistence of fetal hemoglobin than in those with deltabeta thalassemia.

Base Sequence↗
PubMed1978

Maintenance of a certain rumen protozoal population in a continuous in vitro fermentation system.

A continuous culture system suitable for maintaining certain rumen protozoa was developed by modifying the procedure of Walter and Pilgrim (R.A. Weller and A.F. Pilgrim, Br. J. Nutr. 32:341-351, 1974) to include a dialyzing system. The concentration of ciliate protozoa, the pH value, and concentrations of volatile fatty acid and ammonia-N could be maintained within normal rumen limits for more than 15 days by appropriate choice of mechanical agitation and of the amount of substrate and physical form of the substrate bags. The average concentration of protozoa in the free fluid around the substrate was about 10% that in the fluid squeezed from solid digesta residues. More than 10(6) protozoa per ml was present in the fresh substrates only 2 h after supplying the substrate. These facts suggest that sequestration of the protozoa among particulate digesta is an important factor in maintaining the concentration of protozoa.

Animals↗