Excitatory effect of adenosine on neurotransmission is due to increase of transmitter release in the hippocampal slices.

Adenosine has dose-dependent biphasic excitatory and inhibitory effects on neurotransmission in the hippocampus. The mechanism of the excitatory action is not known although that of the inhibitory action has been well analyzed. Here we report on the mechanism of excitatory action of adenosine, using hippocampal slices. Studies of intracellular recordings of CA3 pyramidal neurons showed that the amplitude of EPSP was dramatically enhanced by application of adenosine at low concentration (0.1 microM) without changing resting membrane potentials, membrane conductance or the threshold for spike generation by injecting current pulses. On the other hand, the presence of adenosine at a concentration of 0.1 microM during electrical stimulation to the slices increased 1.7 times the release of glutamate, an excitatory neurotransmitter in the hippocampus. These results indicate that the excitatory action of adenosine at low doses is due to the increase of transmitter release.     

Enhancement of CD3-mediated thymocyte apoptosis by the cross-linkage of heat-stable antigen.

Heat-stable antigen (HSA) is a murine differentiating antigen that is expressed on both CD4-CD8- double-negative and CD4+CD8+ double-positive thymocytes but not CD4+ or CD8+ single-positive thymocytes. Effects of anti-HSA monoclonal antibody, R13, on thymocyte apoptosis induced by various stimulations were investigated by a single-cell suspension culture system. Immobilized R13 enhanced the CD3-mediated DNA fragmentation and killing of thymocytes but not the dexamethasone-induced or phorbol myristate acetate-induced killing of thymocytes. Immobilized R13 by itself could not induce thymocyte apoptosis. Soluble R13 enhanced CD3-mediated apoptosis when HSA and T-cell receptor (TCR)/CD3 were co-cross-linked by a cross-reactive secondary antibody. Even without the cross-reactive secondary antibody, soluble R13 enhanced CD3-mediated apoptosis, although a greater than 100-fold increase in the amount of R13 was needed to give a similar enhancement compared with immobilized R13. Neither R13 by itself nor R13 plus secondary antibody induced cytosolic calcium influx, whereas R13 enhanced CD3-mediated cytosolic calcium increase. These results suggest a functional role of HSA in promoting the activation-induced apoptosis of thymocytes and the involvement of HSA in negative selection.     

Biological activities of glycoproteins of HVJ (Sendai virus) studied by reconstitution of hybrid envelope and by concanavalin A-mediated binding: a new function of HANA protein and structural requirement of F protein in hemolysis.

When HANA protein of HVJ (Sendai virus) was denatured by dithiothreitol treatment, concanavalin A added to the system or influenza virus hemagglutinin reconstituted with treated HVJ-envelope to form hybrid by SM-2 dialysis method could not replace a role of HANA for hemolysis. Binding of the treated samples to erythrocytes was restored by them, however. Thus, a hypothesis is proposed that intactness of not only F but also HANA protein of HVJ is required for envelope-cell fusion, in other words, HANA protein of HVJ may play some positive role other than binding in the process of the virus-induced hemolysis.     

Clinical evaluation of flomoxef in pediatrics and a study on the penetration into cerebrospinal fluid

The transfer to cerebrospinal fluid of a new oxacephem antibiotic flomoxef (FMOX, 6315-S) and its clinical efficacy against bacterial infections were investigated. 1. In 3 cases of purulent meningitis, cerebrospinal fluid concentrations of FMOX after one shot intravenous injection of 100 mg/kg during the acute stage of infections were 5.12-6.32 micrograms/ml and ratios of FMOX in cerebrospinal fluid in serum were about 5%. During the recovery stage, cerebrospinal fluid concentrations were about 3.8 micrograms/ml and cerebrospinal fluid/serum ratios were about 3.5%. 2. In 1 case of purulent meningitis, the treatment with FMOX was clinically effective but this case was classified as "unevaluable" because other drug was used concomitantly. FMOX was rated effective in other 2 cases of purulent meningitis. Of 9 cases of pneumonia, FMOX was rated very effective in 8 cases and it was rated only effective in the other. Of 4 cases of bronchitis, the drug was rated very effective in 3 cases and only effective in the other. FMOX was rated very effective against 2 cases of tonsillitis, also. 3. As side effects, thrombocytosis was observed in 3 of 20 cases examined. All cases, however, were deemed unrelated to the FMOX treatment and the side effect was only transient as are often found in courses of recovery from infections.     

Changes in the tumorigenic and metastatic properties of tumor cells treated with quercetin or 5-azacytidine

The effect of quercetin, a flavonoid derivative, on the transplantability (tumorigenicity) and metastatic behavior of mouse tumor cells was studied. BMT-11 c1-9 fibrosarcoma cells were treated in vitro with quercetin, and after cloning by limiting dilution, cell suspensions of each clone were injected subcutaneously (s.c.) into syngeneic C57BL/6 mice at a dose of 2 X 10(5) cells per mouse. Out of 17 clones examined, 8 were nontumorigenic in normal mice ("regressor" clones), whereas these clones were able to grow in immunosuppressed (600-rad-irradiated) mice. Furthermore, 1 out of 9 tumorigenic clones metastasized spontaneously to the lungs despite the very low metastatic potential of the parent BMT-11 c1-9 cells. In contrast, all 15 clones selected from the untreated parental line grew progressively in normal mice with no evidence of metastases. The appearance of both regressor and metastatic clones was also observed after treatment with a DNA hypomethylating agent, 5-azacytidine. These altered phenotypes resulting from treatment with both chemicals, however, were not necessarily stable if maintained in culture for several months. The data suggest that quercetin may be a useful new material for obtaining regressor or metastatic clones from parental tumor lines.     

Experience with microsurgical epididymovasostomy (specific tubule technic: end-to-end anastomosis by the Silber method)

Here, we report 2 cases of epididymovasostomy operation in which good results were obtained. These operations were done for patients whose complaints were male sterility due to obstructive azospermia after bilateral epididymitis. The method of this operation was reported by Silber in 1978 as "specific tubule technique", and excellent results have been reported. Herein, we introduce this technique perhaps for the first time in Japan, and the characteristics of this method are considered. The important factors and characteristics of this method are that it is very reasonable with a high success rate, it is more difficult than microsurgical vasovasostomy, it is a time-consuming operation. Epididymovasography should not be done preoperatively but intraoperatively, if possible and chronic epididymitis should be ruled out by serological study and culture study.     

A study on the effect of (2"R)-4'-O-tetrahydropyranyladriamycin, a new antitumor antibiotic, on reproduction. I. Its effect on the fertility of rats

The effect of a new antitumor antibiotic on the fertility was studied using SD rats. (2"R)-4'-O-Tetrahydropyranyladriamycin (THP) was administered to each rat at 0.01, 0.03 or 0.1 mg/kg daily. Males were given the drug intravenously for 63 days prior to mating and during the mating period; females were given the drug intravenously from 14 days prior to mating until day 7 of pregnancy. All the pregnant rats were sacrificed on day 20 of pregnancy, followed by external, visceral and skeletal observations of their fetuses. Results were summarized as follows. THP, at 0.1 mg/kg, suppressed body weight gain in females during the late period of pregnancy but did not affect body weight gain in males. THP, at 0.1 mg/kg, increased the numbers of dead fetuses and of resorptions. It caused no external, visceral or skeletal anomalies at any dose levels. The results suggest that, in rats, the maximum "no effect" dose of THP is 0.03 mg/kg/day intravenously regarding fertility and fetal development.     

A case of renal cell carcinoma of horseshoe kidney that produced AFP and caused hypercalcemia

A very rare case of renal cell carcinoma of the horseshoe kidney that produced AFP and caused hypercalcemia is reported. The relationship between this renal cell carcinoma and hypercalcemia was obvious, but the mechanism of hypercalcemia was not revealed. The presence of AFP in cancer cells was demonstrated using the "ABC" method.     

Effects of metal-containing drugs taken simultaneously with clioquinol upon clinical features of SMON

In order to explore the effects of metals upon the subsequent onset of several clinical events in SMON, a retrospective cohort study was attempted. Study subjects were 216 "exposed" patients and 149 "unexposed" patients. "Exposure" was defined as the simultaneous ingestion of metal-containing drugs with clioquinol before the onset of neurological disorders. These two cohorts were identified from 531 patients among 832 patients, collected by the nationwide survey in 1975 and 1976. Effects provoked by ingestion of five metals (alminum, calcium, magnesium, copper and bismuth) were evaluated by relative risks with and without adjustment of the total amount of clioquinol ingested. Adjusted relative risks were estimated by maximum likelihood method. Significance of relative risk was determined by its 95% confidence interval. Following major findings emerged from the present analysis. (1) Simultaneous ingestion of Al-, Ca-, Mg-, Cu- or Bi-containing drugs with clioquinol significantly reduced the risk of developing motor disturbances. (2) Risk of developing visual disturbances were favorably modified by Al-containing drugs. (3) Clinical severity was significantly reduced by ingestion of Al-, Ca-, Mg- or Bi-containing drugs. (4) About 2-fold increase in risk of unfavorable clinical course was demonstrated by Al-containing drugs. (5) Onset of both green-fur on the tongue and relapse appeared unrelated to the metal-containing drugs ingested. (6) Combined ingestion of two kinds of metal-containing drugs with clioquinol appeared to yield more favorable effects than single ingestion of metal-containing drugs. (7) Al- or Bi-containing drugs demonstrated the strongest association with clinical features of SMON, followed by the drugs containing Mg or Ca. Cu-containing drugs had little association.