Biomedical subjects

N Tsuyama

Publications and source records attributed to N Tsuyama.

At least 19 recordsLinked to original sources

PubMed1992

Unique association of p53 mutations with undifferentiated but not with differentiated carcinomas of the thyroid gland.

Thyroid neoplasms show a wide variety of lesions varying from slowly growing differentiated adenocarcinomas to rapidly proliferating undifferentiated carcinomas. There has been some histopathological evidence that the undifferentiated thyroid carcinomas are derived from differentiated carcinomas. Moreover, it is suspected that some genetic events might be associated with such changes. In the present study, mutations in the p53 gene were investigated by direct sequencing analysis after polymerase chain reaction amplification of exons 5 to 8, using paraffin-embedded primary tumors and cultured cells. No mutations in exons 5 to 8 were detected in 10 differentiated papillary adenocarcinomas, whereas 6 of 7 undifferentiated carcinomas were found to carry base substitution mutations. Sequencing analysis confirmed mutations at codons 135 (TGC----TGT), 141 (CCC----CCT), 178 (CAC----GAC), 213 (CGA----TGA), 248 (CGG----CAG, CGG----TGG), and 273 (CGT----TGT). The spectrum of mutations (G:C to A:T transitions in 7 of 8) might be a specific feature of the spontaneous cancers. The results strongly suggest that, in human thyroid glands, p53 mutations play a crucial role in the progression of differentiated carcinomas to undifferentiated ones.

Adenocarcinoma, Papillary↗

PubMed1991

SV40 T-antigen is required for maintenance of immortal growth in SV40-transformed human fibroblasts.

Two lines of immortal human fibroblasts were isolated following transfection of TIG-3 cells with plasmid DNA, pMT-1ODtsA, that contained SV40 early gene with a deletion in replication origin and ts mutation in coding sequence for T-antigen. These cells continued proliferation at 34 degrees C, over 565 population doubling level (PDL) which is far over the limited division potential of untransformed normal TIG-3 of 70-80 PDL. When the culture temperature was shifted to 40 degrees C after 70 PDL, they ceased proliferation immediately. One of these immortal clones, SVts8, lost its ts phenotype after retransformation with wtT-antigen gene. These results indicated that the function of intact T-antigen is required for maintenance of immortal proliferation, at least in one of the SV40 transformed immortal clones.

Antigens, Polyomavirus Transforming↗

PubMed1990

[Spinal flexibility and activities of daily living for the thoracic and lumbar spinal cord injured--comparison of a non operated group with an internal spinal fused group].

There has been a great argument in selecting conservative treatment or surgical repair for the spinal cord injury as an early stage treatment. The purpose of medical treatment is to bring a patient back to the society as soon as possible by early intervention and rehabilitation, while preventing complications of the injury. We are faced with a difficulty in determining the superiority between conservative treatment and surgical repair, since no comparative statistical analysis has been available among various rehabilitation methods for the spinal cord injury. We treated 171 patients in the past with traumatic thoracic or lumbar spinal cord injury who were submitted to our hospital for the ADL training purposes. We selected and studied 34 complete paraplegic cases with no complications who started receiving ADL training within 2 months period after the injury from among these cases. (1) Non-ope group was superior in spinal flexibility to internally spinal fused group. (2) Non-ope group reached ADL independence 1.4 months earlier than I.S.F. in case of upper thoracic injury. ADL independence was reached almost at the same time in the lower thoracic injury cases by either treatment. Above all, it is concluded that conservative treatment is more helpful to establish rehabilitation in shorter length of time than surgical repair.

Activities of Daily Living↗

PubMed1989

Usefulness of myelography in brachial plexus injuries.

Ninety brachial plexus lesions have been examined by myelography and the results classified into six types. These were compared against the level of lesion found at exploration of the brachial plexus with electrophysiological investigations carried out during the operation. The results show that myelography can be a reliable and useful pre-exploratory measure to assess the level of the lesion of each injured root.

Adult↗

PubMed1989

Direct nerve crossing with the intercostal nerve to treat avulsion injuries of the brachial plexus.

One hundred seventy-nine patients with root avulsion brachial plexus injuries were treated with direct nerve crossing with the intercostal nerve and 159 cases were followed more than 1 1/2 years after the operation. When suture was done to the musculocutaneous nerve, 90% of 10 children who had operation within 7 months of injury and 81.8% of 110 adults, younger than 40 years with operation within 6 months of injury regained grade 3 or 4 elbow flexion power. This direct method seems to produce better results than those of nerve crossing, which uses intermediary nerve grafts.

Adolescent↗

PubMed1987

Expiratory activity in transferred intercostal nerves in brachial plexus injury patients.

Involuntary activity of transferred intercostal motor units was examined in patients with brachial plexus injury. Since the internal intercostal nerves were detached from the thorax to reinnervate the musculus biceps brachii, it was possible to record pure intercostal motor activity in humans. Respiratory activity was seen in the latter part of the expiratory phase, thus dividing the phase into two substages (E1 and E2) by the onset of the activity. CO2 rebreathing prolonged the duration of the intercostal motor activity and increased the tidal activity as determined from the integration curve. There was a close linear correlation between these two variables. These observations indicate that expiratory activity and its duration are actively controlled in humans.

Adult↗

PubMed1984

Brachial plexus injuries. Prognosis of postganglionic lesions.

One hundred ninety-eight cases of postganglionic brachial plexus injury with no signs of combined damage to preganglionic sites were treated conservatively. Among them, 50 whole, 32 upper and 13 lower type injuries were followed up for at least 2 years and the course of the progression of the individual muscle was observed. In the whole type, 44% showed good functional recovery, although some of them needed reconstructive surgery. Thirty-eight percent recovered usefully only in the muscles innervated by upper roots. Three out of 50 cases did not recover at all. There were no particular differences between the whole and upper types with regard to the recovery rate of the arm muscles. However, the upper type showed better functional recovery than the whole type. If the muscles innervated by upper roots could gain a strength of M1 before 9 months after injury, and muscles innervated by lower roots reached M1 before 12 months, their final results were more than M3. But muscles with a strength of less than M2 at 18 months did not recover to more than M3. The muscular power at 24 months was almost the same as the final results. About half of the postganglionic brachial plexus injuries which did not combine preganglionic lesions showed favorable spontaneous recovery with conservative treatment. At the exploration of the brachial plexus, if the somatosensory evoked potential test is positive, which negates the possibility of root avulsion, and also if there is no definite discontinuity of the postganglionic nerves, it should be treated conservatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1984

Ossification of the posterior longitudinal ligament of the spine.

Ossification of the posterior longitudinal ligament of the spine (OPLL) is a newly recognized entity. As the incidence of this disease was exceptionally high in Japan, the Japanese Ministry of Public Health and Welfare instituted a special commission for the investigation of this perplexing disease; since 1975 this committee has performed an intensive study of 2100 patients with OPLL in Japan. An epidemiologic study was conducted by this group in Japan and in eastern Asiatic countries. Symptoms and disabilities caused by the disease were described. Roentgenographic findings were classified as continuous, segmental, mixed, or localized. OPLL at the thoracic and lumbar levels combined with ossification of the yellow ligament was described, and the risk of spinal cord damage as well as the importance of tomography and computerized tomographic scanning were stressed. No conclusions were reached concerning etiology, but common findings included a generalized hyperostotic tendency, a tendency for abnormal glucose metabolism, and low enteral calcium absorption. A relatively high hereditary occurrence was noted. Conservative and surgical treatment methods were described, with particular reference to spinal canal-widening operations.

Aged↗

PubMed1977

Meitens' syndrome.

This paper reports on Mietens' syndrome which is characterized by mental retardation, growth failure, flexion contracture of the elbows, dislocation of the radius, abnormally short ulna and radius, bilateral corneal opacity, horizontal and rotational nystagmus, strabismus and a small pointed nose with depressed root. This is the second on the Mietens' syndrome.

Abnormalities, Multiple↗

PubMed1977