Changes in cGMP levels on meiosis reinitiation of starfish oocytes

An intracellular level of cGMP (but not cAMP) transiently decreased the reinitiation of oocyte maturation in the starfish, Asterias amurensis. Exogenously applied cGMP inhibited hormone-induced maturation. Methylxanthines inhibited oocyte maturation by suppressing the decrease in cGMP levels. These results suggest that a decrease in cGMP levels is a prerequisite for meiosis reinitiation of starfish oocytes.

[Diphyllobothrium latum infection in Akita Prefecture. Infections occurring from 1974 to 1981 and the clinical effect of paromomycin sulfate]

Forty-one patients, aged 2 to 68 years old, infected with Diphyllobothrium latum in Akita prefecture were treated using paromomycin sulfate from 1974 to 1981. Paromomycin sulfate was administered orally in a single dose of 20, 30 mg/kg or 50 mg/kg. Twenty-three cases expelled tapeworms. However, only 9 (28.1%) out of 32 tapeworms expelled had their scolex. It can be said that all cases were successfully treated with paromomycin sulfate, since they showed the egg-negative on 3 weeks or 1 month after the treatment. The drug was well tolerated and no side effects were encountered in any patients. It was suggested that paromomycin sulfate was effective and also safe therapeutic agent for the treatment of D. latum infection.

Lack of significance of pili in experimental ascending Escherichia coli pyelonephritis

The role of pili as a bacterial virulence factor has been studied. The model used was acute ascending Escherichia coli pyelonephritis in the mouse. Three strains of E. coli were injected in lightly or more heavily piliated phases into 15 mice each. At sacrifice of 13-15 animals 2 weeks later, no significant difference in severity of pyelonephritis was found as judged by numbers of bacteria in the kidney, nor intensity or frequency of gross abscesses. 27 strains of E. coli were order ranked for severity of pyelonephritis produced and compared with intensity of piliation in vitro under conditions designed to maximize pilus formation. No significant difference was found. 15 strains derived from patients in whom infections were confined to the bladder were compared for degree of piliation with 12 strains infecting the kidney. No significant difference was found. These studies do not support a significant role for the degree of piliation as a virulence factor in pyelonephritis.

[Study on the serum concentrations of gentamicin after intravenous drip infusion]

Serum concentrations of gentamicin (GM) were monitored after intravenous drip infusion of 60 mg over 30 minutes, 1 hour and 2 hours. These concentrations were compared with those after intramuscular injection. The mean peak serum concentration obtained at 30 minutes after intramuscular injection (5.09 micrograms/ml) and those obtained at the end of intravenous drip infusion (5.17--6.66 micrograms/ml) were comparable. Serum concentrations decreased to less than 2.0 micrograms/ml at 6 to 8 hours after injection or infusion in all cases except 1 with less body weight than others. Pharmacokinetic analysis showed that the T1/2 of GM ranged from 2.49 to 4.33 hours and that the AUC ranged from 19.66 to 27.09 hr X micrograms/ml. Results obtained in this study suggested that the usefulness of intravenous drip infusion over the time from 30 minutes to 2 hours is equal to that of intramuscular injection in the GM therapy.

Initiation of sperm motility in teleosts

In salmonid fish (rainbow trout and chum salmon) or freshwater cyprinid fish (goldfish), change of potassium concentration or osmolality of the environment surrounding the spermatozoa at spawning in fresh water directly affect the flagellum and regulate the initiation of sperm motility. A change in these external factors induces intraflagellar cAMP through some changes of plasma membrane in flagellum and cAMP triggers the initiation of axonemal movement through activation of cAMP-phosphorylation system in initiation of sperm motility in teleosts.

The periodic change in adenosine 3',5'-monophosphate concentration in sea-urchin eggs

The level of adenosine 3',5'-monophosphate (cyclic AMP) in the eggs of the sea urchin, Anthocidaris crassispina, was found to change periodically after fertilization. The minimum and maximum levels of cyclic AMP were 1.0 X 10(-7)M and 1.5 X 10(-6)M, respectively. The activity of adenylate cyclase in a 105 000 X g precipitate reached a plateau at 20 min after fertilization and stayed constant for at least 2 h. It was also found that 1.0 mM CaCl2 increased the activity of adenylate cyclase in the same precipitate from unfertilized eggs. In contrast, phosphodiesterase activity changed periodically and correlated with cyclic AMP levels in the eggs. Up to a concentration of 1.5 X 10(-6)M cyclic AMP, phosphodiesterase activity was low, but it became activated when the level of cyclic AMP rose beyond this level. These results indicate that the change in the intracellular level of cyclic AMP is regulated mainly by the change in phosphodiesterase activity.

Variables in demonstrating methicillin tolerance in Staphylococcus aureus strains

Certain technical considerations which affected the status of methicillin tolerance in Staphylococcus aureus strains were studied. Methods which consistently demonstrated tolerance or intolerance of a given strain were avoidance of inoculum splashing, use of stationary-phase inoculum, 24-h tube incubation, and minimization of antibiotic carry-over. These studies suggested a need for the establishment of a standardized reference for the determination of tolerance.

[Left ventricular end-systolic pressure and wall thickness relation for the assessment of regional myocardial contractility in man (author's transl)]

In 28 patients (pts) (5 normal subjects (N), 12 pts with valvular heart disease, 6 with cardiomyopathy, and 5 with ischemic heart disease), left ventricular (LV) pressure was measured using Millar's catheter tip transducer simultaneously with LV posterior wall thickness (W) by echocardiography. After the control recording, LV peak systolic pressure was altered by about 30 mmHg from the control level by angiotensin (20 ng/kg/min) or nitroprusside (1 gamma/kg/min) to attain two (18 pts) or three (10 pts) different end-systolic pressure points, determined after the steady state was achieved. LV end-systolic pressure and wall thickness (P-W) relation a the three different end-systolic pressure points was found to be linear (r = 0.996) in each of the 10 pts, suggesting that end-systolic P-W relation is independent of afterload. Isoproterenol infused in 4 pts, which led to an increase in peak positive (+) dp/dt by a mean of 28%, increased the slope of the P-W relation by 43.4% of the control value (P less than 0.001), while propranolol, which led to a decrease in peak (+) dp/dt by a mean of 16.7%, reduced the slope by 27.3% (p less than 0.001). This indicates the sensitiveness of the slope of P-W relation to the inotropic change of the myocardium. In N, the slope of the P-W relation was -29.7 +/0 6.0 mmHg/mm (mean +/- SD), while the value in 4 pts with decreased functional capacity (NYHA III or IV) was significantly lower (-13.7 +/- 2.9 mmHg/mm; p less than 0.001). Thus, the present study suggests that the slope of the end-systolic P-W relation is useful in assessing regional myocardial contractility in man.

[Prediction of the location of left anterior descending coronary artery disease by anterior echocardiography and esophageal echocardiography (author's transl)]

In 11 normal subjects and 30 patients (pts) with left anterior descending coronary artery (LAD) lesion, the left ventricular anterolateral wall (LVAW) was investigated by esophageal echocardiography (Eso Echo) and the interventricular septum (IVS) by conventional anterior echocardiography (Ant Echo). The location of LAD obstruction, either proximal (20 pts; P-group) or distal (10 pts; D-group) to the first septal branch, was confirmed by coronary arteriography. Twenty-two of the 30 pts with LAD lesion had anteroseptal myocardial infarction (ASMI) and the remaining 8 had angina pectoris. Of the 30 pts, 20 pts including 13 pts with ASMI had normal systolic excursion of IVS. On the other hand, LVAW excursion was below 8 mm in 28 of the 30 pts with LAD lesion compared to the value of the normal subjects (10.8 +/- 1.7 mm; range = 8--13 mm). The sum of the values of IVS and LVAW excursions in the pts with ASMI was significantly lower in the P-group than those in the D-group (p less than 0.001). In the P-group, the beginning of both systolic IVS and LVAW excursion delayed significantly (IVS: 118 +/- 47 msec, LVAW: 121 +/- 44 msec from Q wave on ECG) than those of normal subjects, while in the D-group only LVAW excursion was delayed (142 +/- 23 msec) compared to that of IVS (84 +/- 32 msec). Thus, the analysis of the motion of IVS and LVAW obtained by Ant Echo and Eso Echo is useful in predicting the presence of absence as well as the location of LAD lesion.