Potentials evoked by stimulation of the ulnar nerve and the thoracic cord were recorded in the cervical cord of Nembutalized, curarized cats. The sites of the spinal cord stimulated or recorded therefrom were cooled, all together or independently, in 30 cats, and the effects of the cooling on the evoked potentials were investigated. In all cases, the peak latency tended to increase. On the other hand, the amplitude gradually decreased in the cats in which the stimulation site was cooled, gradually increased in the cats in which the recording site was cooled, and transiently increased when the whole area extending from the stimulation site to the recording site was cooled. In 20 cats, the effects of cooling on the anoxic spinal cord were studied. In the hypothermic cats, the evoked potentials disappeared in 24 min, and in the normothermic cats in 13 min. The difference was statistically significant (p<0.01). This indicates that cooling could counteract the effects of anoxia to a certain extent.

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The purpose of this study was to investigate the effects of voluntary running on the glucose metabolism in isolated adipocytes. Male rats of the Wistar strain, 5 weeks old were separately fed on usual rat food in cages equipped with a rotating wheel. The control rats were kept in small cages without wheels for 8 weeks in both experiments. The exercised rats ran approximately 2 km/day during this period.
There were significant differences in the body weights and the weights of the epididymal fat pads between the exercised rats (373.5±10.3g SEM and 4.2±0.3g SEM) and the sedentary rats (437.8±17.6g SEM and 7.9±0.3g SEM) (p<0.05 in both cases).
The rate of [U-¹⁴C]-glucose oxidation measured by ¹⁴CO₂ production in adipocyte cultures showed a tendency toward greater stimulation in the exercised rats than in the sedentary ones, both when no insulin was added to the incubating medium (0.42±0.18% SEM vs. 0.11±0.02% SEM, p<0.10) and when insulin was added (0.81±0.36% SEM vs. 0.15±0.02% SEM, p<0.05). Hexokinase activity in the cells also seemed to be more stimulated in the exercised rats than in the sedentary ones.
Conversion of [U-¹⁴C]-glucose to triglyceride was not affected significantly in the above experiment either with respect of the exercised rats vs. sedentary rats or with respect of the presence of insulin in the incubating medium.
The number of insulin receptors and affinity constants of adipocytes in both groups was measured by Scatchard analysis. There were three times more binding sites in the exercised rats than in the sedentary ones (93.4×10⁸vs. 29.7×10⁸ sites/10⁵ cells). However there was no difference in affinity constants of the receptors in both cases, Ke (2.8×10⁸vs. 2.7×10⁸ M^-1) and Kf (0.9×10⁸vs. 1.0×10⁸ M^-1) which were calculated by the "negative cooperative theory".
These results indicated the stimulative effects of voluntary running on insulin sensitivity, the rate of glucose transport and glucose oxidation in rat adipocytes.

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The purpose of this study was to determine the usefulness of relaxation time of nuclear magnetic resonance in evaluating biomechanical functions of human lumbar discs. Using L₃-L₄ disc-body units obtained from fresh human cadavers en bloc, proton density imaging was performed with a NMR-CT. Furthermore, intradiscal pressure, tan δ, dynamic stiffness, and relaxation time were measured.
The results were as follows: Proton density imaging was useful in detecting the degeneration of the human lumbar disc. Intradiscal pressure, tan δ, and relaxation time decreased with advancing age whereas dynamic stiffness increased. The correlation coefficient of relaxation time to tan δ and dynamic stiffness was 0.80 (p<0.01) and -0.67 (p<0.05), respectively, which reflected dynamic viscoelasticity of the human lumbar disc.
In conclusion, relaxation time seems to be useful in evaluating biomechanical functions of human lumbar discs.

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In order to clarify the distribution pattern of the pulmonary vessels, which are one of the supply sources of small-sized lung cancers, we studied tumors of less than 3.5 cm in diameter, which were made available to our department, by pre-operative pulmonary angiography, as well as microangiography of the surgically resected lung.
Morphological study of the pulmonary arterial trees in various tumors revealed that they may be classified into either highly vascular or poorly vascularized subtypes. In addition to the morphological study of the pulmonary arterial trees, a correlative study of the extent of the area covered with the intraneoplastic pulmonary arteries and the tumor area was attempted.
In the highly vascularized group, moderate or highly differentiated adenocarcinoma or squamous cell carcinoma, or alveolar cell carcinoma were observed. In the latter group, poorly differentiated adenocarcinoma, large cell or small cell type undifferentiated carcinoma were observed.
Thus it is concluded that visualization of vessel distribution in the tumor parenchyma is made possible by the technique of selective pulmonary angiopathy which leads to identification of the detailed histological patterns and degree of differentiation.
This may offer very versatile diagnostic information on the efficacy of selective pulmonary anti-cancer infusion therapy against small-sized lung cancers which originate mainly in the peripheral region.

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Repertoire sizes of T cells and B cells were estimated by frequency studies using mouse helper T cell clone D10G4.1 (D10 for short) and monoclonal antibodies raised against the antigen recognition structures on D10 cells. The soluble form of these antibodies was capable of activating D10 cells to proliferate in the presence of exogenous IL-1. Moreover, among the heterogeneous peripheral T cells, there is a population of cells which respond to those antibodies.
Normal spleen B cells were non-clonally activated by LPS in limiting dilution cultures and the supernatant was tested for its activation capacity on D10 cells. Precursor frequencies of B cells which produce D10 activating antibodies were in the range of one in millions. The presence of D10 cells in the limiting dilution cultures increased this frequency by a factor of more than ten.
For the estimation of frequencies of a given T cell clone which is activated by anti-D10 antibodies, normal spleen T cells were activated either by beads coupled monoclonal antibodies or by Con A followed by specific soluble antibodies in the limiting dilution cultures, and thereafter specific proliferation was assayed. A group of monoclonal anti-receptor antibodies gave rise to a single hit curve with relatively low frequency of one in 10⁴ to 10⁵. Another group of antibodies revealed in addition to the low frequency population, a higher frequency population of one in thousands.
The data taken together suggest the frequencies of mutually interactive B and T cells are in the range of one in 10⁴ to 10⁵, while among T cells, there can be seen another population of cells of ten to a hundred fold higher frequency. Consequently, direct idiotype-antiidiotypic interactions between lymphocytes should occur only once in 10⁸ to 10¹⁰ cells in the normal unstimulated immune system. Thus, it is more likely that interactions will take place between cells of more degenerated specificities. The implications of these findings in favour of multiple levels of connectancy among T cells which reflect the multiple levels of affinity of the recognition complex of T cells are discussed.

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Bronchial sensitivity and reactivity in 60 patients with bronchial asthma was measured using the Astograph and simultaneous transcutaneous oxygen tension [PtcO₂].
In spite of increasing respiratory resistance, there were some cases in which PtcO₂ did not show remarkable decrease.
The PtcO₂ percentage was defined as (basal value of PtcO₂ - bottom value of PtcO₂) / (basal value of PtcO₂).
The correlation between PtcO₂% and the basal value of PtcO₂ was relatively high (r=0.42, n=58, p<0.005).
The correlation between PtcO₂% and V50/Ht or V25/Ht was also relatively high (r=0.41, n=45, p<0.01, r=0.49, n=45, p<0.001, respectively).
In some cases of small airway obstruction or low basal value of PtcO₂, the PtcO₂% was smaller.
The patients of over 70% in FEV_1.0/VCP were in accord with that of over 70 mmHg in the basal value of PtcO₂.
The results suggest the recommended basal value of PtcO₂ to measure bronchial sensitivity and reactivity may be over 70 mmHg.

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In order to examine the control mechanism of ferritin (Fr) and transferrin (Tf) synthesis depending on intracellular iron levels, the rate of ¹⁴C-leucine incorporation into those proteins was investigated by cell culture of isolated hepatocytes obtained from iron deficient, iron injected and control rats. The effects of iron (ferric ammonium citrate: FeAC) and (diferric Tf: 2FeTf) or desferrioxamine (Dfo) in culture media were also examined. Serum iron, TIBC and Hb levels of iron deficient rats, which were fed an iron deficient diet for 2 and 4 weeks were significantly lower than the control. However serum iron and TIBC levels of iron injected rats which had received 30 and 45 mg iron as iron dextran 18 h before sacrifice were approximately ten times higher than the control group.
The time course of ¹⁴C-leucine incorporation into Fr and Tf was investigated at the 60, 120 and 180 minutes stages of the culture. Fr synthesis was increased by the amounts of iron injected, whereas Tf synthesis showed a negativeresponse to iron. The ¹⁴C activities in Fr and Tf detected from culture media were proportional to those in hepatocytes. The percentage of nonglycosylated Fr was 82.0-91.4% for total Fr in the culture media in every experiment, which was measured by the affinity of glycosylated Fr to Con A-Sepharose (Con A). This result suggested the leakage of cytosol Fr through the cell membrane instead of specific secretion of the sialated protein. The efficiency of Fr and Tf synthesis was positively or negatively proportional to cellular iron contents respectively. And the curves of ¹⁴C-leucine incorporation into both proteins, calculated as the sum of those in hepatocytes and culture media intersected at the point between the 30 mg iron injected and control groups. The addition of FeAC or 2FeTf into the culture media had an indistinct effect on Fr and Tf synthesis, whereas there was a significant decrease for Fr and a slight increase for Tf formations in the Dfo supplement. These results showed the influence of cellular iron levels in Fr and Tf synthesis.

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The effects of exercise on the frequency of ventricular premature contraction (VPC) and the clinical implications thereof were studied in 95 patients. Patients with ischemic heart disease and severe congestive heart failure were excluded from the study. The patients were divided into 7 groups according to changes in the frequency of VPC during and after exercise. Clinical background, exercise parameters and the efficacy of antiarrhythmic drugs were compared among these 7 groups. Plasma catecholamine concentration was measured in 34 patients, with a group of 12 healthy subjects serving as controls.
An increase in the frequency of VPC both during and after exercise was observed in 16 patients (Group II). In comparison with the other groups, this group was older, and exhibited a higher incidence of underlying heart disease, lower tolerance to exercise and more serious ventricular arrhythmias. Beta-blockers were the most effective treatment for this group. However, plasma catecholamine concentration was not significantly higher in this group than it was in the other groups or the healthy subjects.
A decrease in the frequency of VPC during exercise and an increase after exercise was observed in 25 patients (Group DI). This group also exhibited a high incidence of underlying heart disease and serious ventricular arrhythmias. The daily frequency of VPC was highest in this group. Class I and IV antiarrhythmic drugs were the most effective treatment. Although plasma catecholamine concentration was not significantly different from that of the other groups or the group of healthy subjects, a shorter QT interval was observed after exercise as compared with the healthy subjects. In this group, therefore, the mechanism of VPC may be related to a disturbance in the rate-adaptation of the QT interval, causing nonuniformity in the refractory period of the ventricular muscle.
A decrease in the frequency of VPC during and after exercise was observed in 26 patients (Group DD). As compared with the other groups, this group was younger, and exhibited a lower incidence of underlying heart disease and a higher tolerance to exercise. This group was thus regarded as comprising the less severe cases.
Seventeen patients showed no change in the frequency of VPC during exercise and an increase after exercise (Group UI). This group had the second highest average age and exhibited the lowest daily frequency of VPC. The incidence of underlying heart disease and serious ventricular arrhythmias fell between that of Groups II/DI and Group DD.
In conclusion, the new classification emerging from this study may yield important information relating to the severity of VPC and antiarrhythmic therapy. The study may also stimulate further study into the mechanism of VPC.

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