The shape changes in rabbit platelets induced by ADP, NEM, KCN, PGE, , aspirin or distilled water were investigated using Born's method and electron microscopy. The following results were obtained :
1) The optical density of EDTA-PRP was increased rapidly after the addition of ADP, NEM or distilled water. ADP-induced increase in optical density has been thought to be resulted from the shape change of platelets. It could be confirmed by electron microscopy that the change in optical density was due to the morphological change in platelets.
2) When ADP was added to PRP, platelets changed their shape from “disc” to “spiny sphere” with a marked pseudopodia formation. Both microtubules and granules were concentrated in the center of platelet. This type of morphological change was followed by the platelet aggregation.
3) The platelets treated with NEM became also spherical and posessed several number of pseudopodia. As compared to ADP-induced changes, however, the pseudopodia were much shorter, microtubules were destroyed and granules were not concentrated. This kind of morphological change was not followed by the platelet aggregation. The same kind of change was introduced by the addition of distilled water.
4) The optical density of PRP was also increased by addition of KCN and PGE₁, but no significant change in platelet morphology was found by electron microscopy.
5) Aspirin also induced no changes in the shape of platelets.
6) From these results, the relationship between platelet shape change and aggregation of platelets was discussed, and it was suggested that the contractile proteins in the platelets might play an important role in such a shape change as well as the aggregation of platelets.

View full abstract

Changes in the heart rate, blood pressure and ECG during the fiberoptic gastroscopy were studied in 77 cases. The heart rate and the diastolic pressure were already significantly increased following premedication before the insertion of the gastroscopy as compared with the values at the outpatient clinic. Further increase in the heart rate was observed during the gastroscopy, especially at the time of insertion. The diastolic pressure was also elevated by the insertion. Although similar elevation of the systolic pressure during the examination was observed, the change was not remarkable.
Ventricular and/or supraventricular premature beats appeared in 22 cases (28.6%) during the examination. The incidence of the cardiac arrhythmias was remarkably high in the patients above the age of 50 years. A significant ST-T change was induced in 6 cases including 3 cases with normal resting ECG. However, no patient complained of anginal chest pain during the examination, and serious cardiovasculay complications were not oberved in the present series.
Possible usefulness of beta-adrenergic blocker for the prevention of tachycardia and arrhythmia was suggested.

View full abstract

Total knee prosthesis for reconstruction of knee joint makes remarkable progress. Presently, two types of prosthesis are available. One is Hinge-type prosthesis and another is Hingeless-type. Hingeless-type prosthesis duplicates the normal movement of the knee joint, but it requires to maintain the normal intrinsic stability of the knee joint. Hinge-type prosthesis has the joint stability in itself, so it is suitable for severely destructed knee, but it does not allow the physiological polycentric movement of the knee joint, which are rotation, gliding and pseudohinge motion. Hinge-type prosthesis allows monocentric movement only.
We applied the Hinge-type knee joint prosthesis for two cases, one of which was giant cell tumor on the femoral condyle and another was the same tumor on the high tibial region. Postoperative breakage of joint part of the prosthesis did occur in both of the cases, in the femoral case on eleven months and in the tibial cases on two years five months after the surgery. From the findings of broken surface of the prosthesis, it was apparently concluded that the breakage was occured by rotatory stress which was repeatedly given to the joint part by daily living activity. Biomechanical relationship between Hinge joint and physiological knee joint movement was discussed.

View full abstract

The technique for mapping regional organ function by means of the radioisotope (RI) imaging system, is presented. A mathematical model used for constructing functional images is one compartment model, which consists of theoretical disapperance of RI-tracer in blood X₁ (t) and uptake of RI-tracer in tissue X₂ (t). Sum total X (t) of X₁ (t) and X₂ (t) is expressed with X (t) =a+b exp (-Ct), which is obtained as results of the curve-fitting by Cornell's method for the observations.
Using the coefficient a, b, C obtained with curve-fitting, parameters of regional organ function derived from the one compartment model are calculated and the maps of each parameter are constructed. Results of applications of the functional imaging technique for clinical studies (i.e., thyroid-dynamic image with Tc-99m-pertechnetate, liver dynamic image with Tc-99m-Sn-colloid and myocardial dynamic image with N-13 ammonia) are presented.
Moreover, the relation between functional parameter calculated (for example, global incorporation rate constant, relative concentration coefficient, etc) in thyroid function studies and thyroid Tc99m-earlier uptake ratio (%) has been discussed by carrying out regression analysis.

View full abstract

We reported previously about the method of constructing functional images, which is based on the one compartment model expressed with X (t) =a+b.exp (-ct). In this report, various errors introduced on functional images have been assessed quantitatively. Generally, the magnitude of the parameter errors in the functional image depends on the following factors : (1) dose of RI-tracer, (2) conditions of data acquisition, (3) characteristics of the radioisotope imaging system, (4) method of the data processing technique when construct the functional images.
In our studies, the parameter errors resulting from fitting exponential function X (t) as a function of RI-tracer dose, without or with the nonuniformity correction and the dead time loss correction, the manner of determination of t =0, the amplitude ratio and the magnitude of the exponent of the function, are estimated experimentally and theoretically, under the fixed conditions of data acquisition.
The results indicates that it is important to define the method of determining the point of t = 0 and to adopt the method which the accuracy and the precision of fitting exponential functions are independent of the dose of RI-tracer and the characteristics of the observations.

View full abstract

Fifty three previous chain-saw operators, aged 30 and over, under the juristdiction of M Forestry Bureau were examined for fingertip skin temperature after 60 seconds immersion in cold water (4°C), and later recovery of fingertip skin temperature. The subjects included 14 workers with Raynoud's phenomenon history (R (+) group) and 39 workers without such history (R (-) group)
The main findings were as follows :
1) The R (+) group could not be differentiated from the R (-) group by the recovery curve which was obtaind by plotting the fingertip skin temperature at 1 minute intervals for 10 minutes after the end of immersion.
2) The recovery of the initial fingertip skin temperature tended to differ quantitatively in R (+) and R (-) groups.
In view of this, T_t was calculated by the following formula :
T_t= (T₁+T₂+T₃) -3T₀
To was the fingertip skin temperature at the end of immersion. T₁, T₂ and T₃ were the fingertip skin temperatures at 1, 2, and 3 minutes after the end of immersion, respectively.
In this results, T_tof less than 11 was found in 13 cases of the R (+) group (92.9%) and in 17 cases of the R (-) group (43.6%). The difference between two rates significant (P <0.01). The sensitivity value in the above division was 92.9% and the specificity value was 56.4%.
Thus T_t was found to be a effective index for the classification into R (+) and R (-).

View full abstract