Suppressor cells in levamisole-treated mice: a possible role of T-cell-mediated feedback suppression in the drug-induced suppression of the humoral immune response

The suppressive effect of levamisole (LMS) on the primary IgM plaque-forming cell (PFC) response to sheep erythrocytes in mice was studied. The suppressive effect of LMS on day 4 PFC response was found to be modified by dose, the timing of drug administration, and the amount of antigen injected. The experiments, using an inhibitory dose of 10 mg/kg LMS, showed that: 1) T cells play an essential role in LMS-induced suppression; 2) antigen-specific suppressor cells are induced in the spleen of LMS-treated mice; 3) the spleen cells from LMS-treated donors either suppress or enhance the PFC response in the recipients, depending on the amount of antigen injected and the number of spleen cells transferred; and 4) a dose of 10 mg/kg LMS, which is inhibitory when assessed on day 4 PFC response, actually enhances the response three and a half days after the immunization. These results suggest that LMS induces precursors of both helper and suppressor cells, and their differentiation and/or maturation to LMS-primed antigen-specific suppressor T cells are modulated, at least in part, by T-cell-mediated feedback suppression.     

The metastatic patterns of gastric cancer from its histopathological characteristics in the primary lesion--particularly in relation to peritoneal dissemination and liver metastases

The purpose of this study was to catagorize the metastatic patterns of advanced gastric cancer into liver and peritoneal metastases from the stromal behavior of the primary lesion in 278 patients. According to our data, peritoneal disseminations were encountered 5.0% of the medullary type, 30.0% of the intermediate type and 38.0% of the scirrhous type, while the corresponding figures for liver metastases were 28.8%, 6.0% and 1.9%, respectively. The differences among the three types were significant with both patterns of metastasis. From the present data, we assume that the histological pattern in the stroma of primary gastric cancer shows the biological behavior of cancer growth and metastatic patterns, particularly in close relation to peritoneal dissemination and liver metastases.     

Transmitral blood flow velocity patterns evaluated by pulsed Doppler echocardiography in diagnosing transient myocardial ischemia

To evaluate the influences of transient myocardial ischemia on transmitral blood flow velocity patterns, pulsed Doppler echocardiography was performed during coronary artery occlusion in 10 anesthetized open-chest dogs, and also during esophageal pacing or the administration of dipyridamole in 79 patients with coronary artery disease (CAD), and in 19 control subjects. During occlusion of the coronary artery, an abrupt decrease in the peak velocity of the rapid filling wave (R) was noted within one min simultaneously with rapid decrease of % wall thickening in the ischemic regions. The peak velocity of atrial filling was augmented compensatorily. Although the transmitral blood flow velocity pattern did not change in the controls with esophageal pacing, changes similar to those which were obtained during experimental studies were demonstrated in CAD patients. There were no significant differences between transmitral blood flow velocity patterns of patients with multivessel disease and those with single vessel disease. Ischemic changes in transmitral blood flow velocity patterns were not demonstrated in patients with mitral regurgitation. Sublingual nitroglycerin normalized post-pacing abnormal blood flow velocity patterns. In contrast, after the intravenous administration of 0.56 mg/kg of dipyridamole, R and A were increased and the A/R ratio was unchanged both in CAD patients and the control groups. Deceleration time, or the half time, was prolonged during both provocation tests in CAD patients, and these changes were transient and were restored within several min. Furthermore, they were noted more frequently than was the development of ST depression on ECG, or chest pain. These findings indicate that the transmitral blood flow velocity patterns obtained by pulsed Doppler echocardiography are useful for detecting transient myocardial ischemia, though they have limitations in diagnosing the extent of coronary artery disease.     

Malignant parotid gland tumors and facial nerve paralysis

During the last three decades, 586 cases of parotid gland tumor have been extirpated in our clinic. The tumors were malignant in 170 cases and, of these, facial nerve paralysis was observed at first examination in 59 patients. This paper deals with the retrospective study of these cases and is chiefly concerned with the histological types and facial nerve paralysis.