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Biomedical subjects

Y Ohnuki

Publications and source records attributed to Y Ohnuki.

At least 55 records · Page 3Linked to original sources

Fall in forearm skin temperature during grade walking on a treadmill.

Thermoregulatory responses were observed in 7 male subjects during grade walking at different speeds of between 0.5 and 9 km/hr. The total heat productions (H) in uphill and downhill walking are defined as metabolic heat production (M)--external work (W) and M + W, respectively. During 60 min exercise at 20 degrees C, r. h. 40%, rectal temperature increased to levels dependent on M and independent of H. The sweat-rate varied in proportion to H, and not to M. During 10 min exercise, the environmental conditions (28 degrees C, 40% r.h.) and work intensities were set so that changes in skin temperature could be observed without the interference of sweating. The results indicated that the fall in forearm skin temperature was correlated to M, and not to H. Our previous studies showed that cutaneous vasoconstriction persisted during exercise and that raised work intensities increase the surface area affected by lowered skin temperature. These findings suggest that the rise in core temperature during exercise results from the decreased dry heat loss due to a fall in skin temperature.

Adult↗

Neuromuscular blocking in acutely tetanus intoxicated mice.

The effects of tetanus toxin on neuromuscular transmission of mice in acute intoxication produced by intravenous injection of a large amount of the toxin were examined by (1) recording the phrenic nerve impulses, the electromyograms (EMGs) of the diaphragm and the electrocardiograms, and (2) the evoked EMGs of the gastrocnemius muscle in response to electrical stimulation of the sciatic nerve. The evoked EMGs of the gastrocnemius muscle were analyzed in terms of kinetic and tonic components by their different latencies. Just before death of animals, the EMGs of the diaphragm appeared with some delay relative to the corresponding phrenic discharges. Finally, the EMG of the diaphragm disappeared even in the presence of phrenic discharge, but cardiac electrical activities continued. The amplitudes of the evoked EMGs of the gastrocnemius muscle invariably became low before death, but the muscle action potential could be recorded by direct muscle stimulation for several minutes after death. The latencies of the evoked EMGs were constant until about the middle of the survival time when the latencies suddenly became prolonged. The longer latency was the same as that of the tonic action potentials. Thus, in acutely tetanus-intoxicated mice, neuromuscular transmission was blocked rapidly and the kinetic component of the muscle was blocked earlier than the tonic component.

Action Potentials↗

Fall in skin temperature during exercise observed by thermography.

Monochromatic and colored thermographies were used to visualize skin temperatures during exercise without involvement of sweating. Skin temperature began to fall immediately at the onset of exercise, remained low during exercise and rose rapidly after cessation of exercise. Increased work intensities produced a proportional fall in skin temperature and greater surface area of lowered temperature.

Adult↗

Differential properties among clones of simian virus 40-transformed human epithelial cells.

Monolayer cultures of human prostatic epithelial cells were exposed to SV40 virus at 35th population doubling. Clones were isolated from infected plates after growth had ceased on the control plates. The nuclei of these clones were virtually all positive for viral T-antigen by immunofluorescence. When the properties of three of these lines were compared to those of normal cells, they were found to have altered morphology, ultrastructure, chromosomes, and growth behavior. All transformed lines had reduced serum dependence and were capable of growing in soft agar. However, their reduced serum dependence was not due to reduced growth factor requirements because each subline's response to growth factors was different.

Agar↗

Chromosomal analysis of human prostatic adenocarcinoma cell lines.

Although detailed cytogenetic analysis has been carried out in many types of cancer, there is little information on the chromosomal makeup of prostatic cancer cells. Karyological analyses of cell lines derived from both metastatic and primary prostatic carcinoma have been carried out by Q-, C-, and sequential banding techniques. The metastatic line, PC-3, isolated from a bone marrow specimen, is an established epithelial line which is tumorigenic in nude, athymic mice and forms colonies in semisolid agar suspension. A subline, PC-3/M, was isolated from a PC-3-induced mouse tumor. Karyotypic analysis of PC-3 by Q- and C-banding showed the cells to be aneuploid at all culture passage levels. The modal chromosome number shifted from 62 to 55 between the 5th and 50th passages. PC-3 has a unique karyotype. Chromosomes 2, 3, 5, 15, and Y were always absent. At least 11 different marker chromosomes were observed. The subline, PC-3/M, had a similar karyotype and retained the parental PC-3 markers. PC-3/M had a more restricted chromosomal frequency distribution range. Nearly 73% of the PC-3/M cells examined had 60 or 61 chromosomes in contrast to the wide distribution seen in PC-3. Silver staining for nucleolus organizer regions indicated that the number of functional nucleolus organizer regions in PC-3 was proportional to the number of acrocentric chromosomes. Banding analysis of PC-5-PI isolated from primary prostatic adenocarcinoma indicated that this line also had a characteristic karyotype with 28% pseudodiploid and 72% pseudotetraploid components. All metaphases examined were partially trisomic in chromosome 9 and lacked a demonstrable Y chromosome.

Adenocarcinoma↗

Establishment and characterization of a human prostatic carcinoma cell line (PC-3).

The establishment, characterization, and tumorigenicity of a new epithelial cell line (PC-3) from a human prostatic adenocarcinoma metastatic to bone is reported. The cultured cells show anchorage-independent growth in both monolayers and in soft agar suspension and produce subcutaneous tumors in nude mice. Culture of the transplanted tumor yielded a human cell line with characteristics identical to those used initially to produce the tumor. PC-3 has a greatly reduced dependence upon serum for growth when compared to normal prostatic epithelial cells and does not respond to androgens, glucocorticoids, or epidermal or fibroblast gowth factors. Karyotypic analysis by quinacrine banding revealed the cells to be completely aneuploid with a modal chromosome number in the hypotriploid range. At least 10 distinctive marker chromosomes were identified. The overall karyotype as well as the marker chromosomes are distinct from those of the HeLa cell. Electron microscopic studies revealed many features common to neoplastic cells of epithelial origin including numerous microvilli, junctional complexes, abnormal nuclei and nucleoli, abnormal mitochondria, annulate lamellae, and lipoidal bodies. Overall, the functional and morphologic characteristics of PC-3 are those of a poorly-differentiated adenocarcinoma. These cells should be useful in investigating the biochemical changes in advanced prostatic cancer cells and in assessing their response to chemotherapeutic agents.

Adenocarcinoma↗

Ultrastructure, karyology and immunology of a cell line originated from a human transitional-cell carcinoma.

A cell line (J82) was derived from a poorly differentiated, invasive, transitional-cell carcinoma, Stage T3. The cells have been propagated in vitro for 5 years and showed 100% aneuploidy and a mixed epithelial-fibroblastic morphology. The majority of cells contained 2Y chromosomes and several distinctive markers. Peripheral-blood lymphocytes from the donor of the J82 cells were tested sequentially for cytotoxicity toward autologous and allogeneic tumour cells. Autologous cytotoxicity was detected against J82 cells in early in vitro passage. Allogeneic lymphocytes from some patients with transitional-cell carcinoma were also cytotoxic to J82 cells in primary culture. However, selective cytotoxicity by lymphoid cells from bladder-carcinoma patients was not detected against J82 cells in long-term tissue culture.

Carcinoma, Transitional Cell↗

Replicative epithelial cell cultures from normal human prostate gland.

Epithelial cell cultures of the normal human prostate gland were established. The subculturing of these cultures was accomplished with a novel nonenzymatic technique. These cultures were defined as normal epithelial cells on the basis of ultrastructure, karyotype, and inability to grow in soft agar.

Cell Adhesion↗

Fall in skin temperature during exercise.

During light work using the arm in a warm environment, skin temperatures of the arms and chest fell and remained at lower levels during work. The fall in skin temperature during work was not observed in a cool environment. The fall in skin temperature was nearly proportional to work intensity and was observed in both static and dynamic work. Leg work of moderate intensity produced an initial decline and a subsequent rise in skin temperatures of the hands, thighs and legs. A significant fall in skin temperature was observed not only in the foot but also in inactive regions such as the epigastrium. The mean skin temperature remained practically unchanged during work. The fall in skin temperature during work was not due to increased evaporative cooling, but was the result of segmental vasoconstriction probably caused as a reflex in the spinal cord by non-thermal afferents from exercising muscles or moving tissues. The effect of thermoregulatory vasodilation was reduced by the reflex vasoconstriction caused by non-thermal factors. The rise in internal temperature during work could be explained by decreased heat loss due to persistently lower skin temperature.

Adult↗

Neuroimaging on delayed postanoxic encephalopathy with lesions localized in basal ganglia.

A 59-year-old woman suffered from prolonged hypotension with myocardial infarction. Sixteen days after the episode, she showed bradykinesia, gait disturbance, and postural tremor. MRI revealed low signa intensities in the bilateral caudate nuclei and putamen on the T1-weighted image and high signal intensities on the T2-weighted image. PET with 18F-FDG revealed a severe decrease in glucose metabolism in bilateral basal ganglia. It is concluded that prolonged hypotension may induce localized delayed anoxic lesions in basal ganglia.

Basal Ganglia↗

Chronological changes in cerebral air embolism that occurred during continuous drainage of infected lung bullae.

We present a 43-year-old man with cerebral air embolism that occurred during continuous drainage of infected lung bullae. This complication is extremely rare, and may have been caused by the passage of air into the pulmonary venous circulation through a bronchovenous fistula and/or damaged pulmonary vessels. Air densities were demonstrated along the right frontal gyri on a CT performed 1 h after the onset of embolism, then moved to the deep cortex after 2.5 h. Three days later, a cortical infarct accompanied with extensive white matter edema in the right frontal lobe was confirmed by MRI. These CT and MRI findings may indicate the passage of intravascular air from the superficial to the deep cortex and subsequent cerebral infarction.

Adult↗