Unusual Mechanism in the Initiation of the Paroxysmal Supraventricular Tachycardia in a Patient with WPW Syndrome

A heretofore unreported unusual mechanism in the initiation of the paroxysmal supraventricular tachycardia (PSVT) in a patient with WPW (Wolff-Parkinson-White) syndrome was observed using His bundle recordings. The patient initially had some degree of AV conduction disturbance at the level of the AV node. A premature atrial impulse initially activated the ventricle exclusively through the accessory pathway and the same impulse re-excited the ventricle via the AV nodal-His axis after finishing the pure pre-excitation with marked prolongation of the AH and the HV intervals. After finishing this double ventricular response it traversed to the atrium to produce the PSVT.     

Relationship Between Human Chorionic Gonadotropin and Behavior of T Cell Populations in Early Pregnancy

ABSTRACT: Sequential observations of lymphocyte sub-populations, response to mitogens, level of plasma human chorionic gonadotropin (HCG), and detection of HCG on the surface of T cells were carried out to study immunological functions in pregnant women early in the fetomaternal relationship. T cell counts determined by the standard method decreased gradually between 5 and 10 weeks of pregnancy but no decline was observed when determined by the modified methods. Minor fluctuation of B cell populations and lymphocyte response to mitogens were within the standard value. Plasma HCG in peripheral venous blood (PVB) increased markedly until 10 weeks of gestation and then declined. T cell poulation in parauterine venous blood (PUVB) was lower than that in PVB. The presence of HCG on the surface of T cells was demonstrated in maternal lymphocytes but not those of control subjects.     

INHIBITION OF TUMOR GROWTH AND ANGIOGENESIS BY VITAMIN D3 AGENTS IN MURINE RENAL CELL CARCINOMA

Purpose

To investigate the effect of active vitamin D3(VD) agents on tumor growth and metastasis.

Materials and Methods

BALB/c mice were inoculated with murine renal cancer Renca and graded doses of 1,25-dehydrovitamin D3 or 1- hydrovitamin D3 were given intraperitoneally every other day beginning on day 1, 3, or 7 and ending on day 9, 11, or 15. Direct cytocidal activity and angiogenic activity were evaluated by 48-hour MTT assay and by the colorimetric method, respectively.

Results

Both VD agents inhibited tumor growth and prolonged the life span of Renca-bearing mice in a dose-dependent manner and both suppressed tumor growth in athymic mice and euthymic mice with eliminated NK activity. Marginal body-weight loss without appreciable hypercalcemia was observed in mice given VD agents. When treatment was delayed on day 7, the VD agents failed to inhibit tumor growth. The MTT assay showed no direct cytotoxicity of VD agents on Renca. Tumor angiogenesis was inhibited to 46 to 30% of the control level by VD agents. Furthermore, VD agents reduced pulmonary and hepatic foci in the metastatic models.

Conclusions

These results suggest that VD agents may be effective as a treatment for renal cell carcinoma, especially when micrometastases are involved.     

Sensitivity to cisplatin determined by the histoculture drug response assay and clinical response of endometrial cancer

This study investigated the value of the in vitro histoculture drug response assay (HDRA) for predicting the efficacy of chemotherapy in patients with endometrial cancer. Specimens were obtained from 115 patients with endometrial cancer treated at Keio University Hospital between 1994 and 2002. Tumor fragments were cultured on collagen sponge gel with cisplatin for 7 days, and cell viability was assessed. The cutoff value of the 50% inhibitory concentration of cisplatin was set at 23 microg/mL. Sensitivity of stage III or IV disease to chemotherapy was investigated, and differences of 5-year progression-free survival between patients with sensitive and resistant tumors were evaluated by the Kaplan-Meier method. Tumors were evaluable in 93.0% of patients (107/115). Among 38 patients in stages III or IV, 23 received chemotherapy containing cisplatin. Seven sensitive tumors did not recur, while recurrence/progression occurred within 6 months in 8/16 patients with tumors showing low sensitivity. Among stages III and IV patients, there was a significant difference of 5-year progression-free survival (P < 0.05) between those with tumors showing high or low sensitivity. Accordingly, the HDRA may predict the efficacy of chemotherapy for endometrial cancer.     

Biocompatibility of Heparin-Coated Membrane Oxygenator During Cardiopulmonary Bypass

Abstract: The biocompatibility of the cardiopulmonary bypass (CPB) circuit, in which an oxygenator is solely heparinized, was assessed by systemic inflammatory reactions as an indicator during CPB. Fourteen patients, 11 males and 3 females, underwent coronary artery bypass surgery and were randomly divided into 2 groups of 7 patients each. For the heparin–coated oxygenator group (Group H), a heparin–coated membrane oxygenator was used in the CPB circuit, and in the control (Group C) an uncoated membrane oxygenator was employed. Systemic inflammatory reactions, such as platelet activation, prostaglandin production, complement activation, and activated granulocyte released substance, were measured prior to, during, and 6 h after CPB. The number of platelets decreased after protamine administration in both groups (14. 5 ±4. 7 times 10⁴/μl in Group H and 13. 8 ± 8. 7 times 10⁴/μd in Group C) and returned to baseline levels in Group H while it remained decreased in Group C at 6 h after CPB. The platelet factor 4 level was significantly lower in Group H (181 ± 40 ng/ml) than in Group C (297 ±131 ng/ml) after protamine administration. Thromboxane–B₂ (TXB₂) rose during CPB in both groups; however, there were significantly different levels of TXB₂ between the 2 groups at 60 min after CPB (293±258 pg/ml in Group H versus 408 ± 120 pg/ml in Group C) and after protamine administration (259 ± 122 pg/ml in Group H versus 709 ± 418 pg/ml in Group C). Plasma concentrations of granulocyte elastase were significantly lower in Group H at 30, 60 and 90 min, immediately after, and post–CPB than those of Group C. Although the oxygenator was solely heparinized in the CPB circuit, it was sufficiently effective to reduce inflammatory reactions during coronary artery bypass operation, and the heparin–coated surface seems to be more endothelium–like.     

Choice of treatments for small hepatocellular carcinoma: Hepatectomy, embolization or ethanol injection

The results of hepatectomy, percutaneous ethanol injection therapy and transcatheter arterial embolization for small hepatocellular carcinoma (HCC) of 3 cm or less in diameter from the published literature were compared with the authors' experiences with surgical treatment. The survival rates for those treated by hepatectomy and ethanol injection were almost the same, being more than 90% at 1 year and 70% at 3 years. The overall results achieved by embolization were inferior to those achieved by the other two therapeutic modalities, although the 1 year survival rate was not worse. The cancer-free survival rates after hepatectomy and ethanol injection were also similar. Most of the patients with small HCC had associated liver cirrhosis or chronic active hepatitis, but the degree of liver dysfunction and the level of hepatic reserve varied. Anatomically, the number, size, and location of the cancer also varies. Choice of treatment for small HCC should be made based upon the degree of liver function and the anatomic status of the cancer. For example, a patient with multiple (more than four) cancer nodules is a good candidate for embolization. Ethanol injection is indicated for a small HCC, deeply seated in a severely diseased liver. Hepatectomy is the first choice for a small HCC situated near the surface of a liver with relatively good liver function.     

Reversibility of organic anion-induced cholestasis: Association with compensatory hypersecretion of biliary phospholipid and protein in the dog

Abstract The effect of a concomitant infusion of organic anions, structurally related phthaleins, on bile flow was studied in anaesthetized dogs. A combination of rose bengal and sulfobromophthalein was found to uniquely and synergistically produce an acute, reversible form of intrahepatic cholestasis (< 10% of control level). This phenomenon was not observed with the administration of those individual organic anions at concentrations previously associated with the induction of intrahepatic cholestasis. The infusion of either a micelle forming bile salt, sodium taurocholate, or a non-micelle forming bile salt, sodium dehydrocholate, rapidly reversed the intrahepatic cholestasis (within 20 min after bile salt infusion). During the choleretic phase immediately following the bile salt infusion, a transient but marked hypersecretion, a disproportionately increased output in relation to that of bile acids, of biliary phospholipid (176% of control level by taurocholate and 138% of control level by dehydrocholate), and an even more striking amount of biliary protein hypersecretion were observed (392% of control level by taurocholate and 357% of control leverl by dehydrocholate). Although the significance of these new post-cholestatic observations requires clarification, it is suggested that the intrahepatic cholestasis induced by organic anions reflects a reversible defect in the mechanism(s) involved in transcellular transport.     

Prevalence of volatile solvent inhalation among junior high school students in Japan and background life style of users

In order to estimate the prevalence of volatile solvent inhalation among junior high school students in Japan and to assess certain characteristics of the lifestyle of these users, the authors surveyed 5240 students 12–15 years of age. This was the first major source of the prevalence of volatile solvent inhalation among junior high school students in Japan, from the point of view of the number of subjects and schools. 1.5% of subjects were students who had inhaled solvents. The regularity of life style rhythm was more significantly disturbed in Lifetime Users than in Non-Users. School life and family life was significantly less relaxed for Lifetime Users than for Non-Users. Drinking alcohol and smoking had a strong relationship with inhaling volatile solvents. The authors suggest that greatly increasing education on the harmful effects of volatile solvents inhalation and increasing the frequency with which the entire family eats dinner together will be an effective prevention strategy in Japan.