The authors examined the usefulness of nested PCR (N-PCR) to detect Mycobacterium tuberculosis (MTB) DNA in CSF for assessing the clinical course of tuberculous meningitis (TBM). N-PCR successfully detected MTB DNA in all nine CSF samples from patients with suspected TBM. During anti-tuberculosis treatments, N-PCR results converted from positive to negative, correlating with the improvement of the patient's clinical condition.

No abstract

To investigate the mechanism of penicillin-induced convulsions, we have studied the effects of penicillin G (PC-G) on GABA-gated chloride ion influx in brain 'microsac' preparations of mice. In the presence of 10(-4) M GABA, PC-G inhibited GABA-gated chloride ion influx in a dose-dependent manner. The dose-response curve for GABA in the presence of 10(-3) M PC-G was shifted rightward and there was a decrease in maximum response. The inhibitory effects of PC-G were not reversed by RO 15-1788, an antagonist of benzodiazepine (BZ) receptors, but were reversed by washing the 'microsac' membranes. Therefore, PC-G probably exerts its proconvulsant effect by inhibiting GABA-gated chloride ion influx. However, it appears not to act through the BZ receptor of the GABA/BZ receptor complex.

No abstract

To clarify the relationship between earthquake occurrence and fluid, we analyzed data from a dense aftershock-observation network with 69 high-gain short-period seismographs installed immediately after the mainshock occurrence (October 21) in the aftershock area of the 2016 Central Tottori Prefecture earthquake. We determined the hypocenters and focal mechanisms of the aftershocks very precisely in the period from October 22 to December 15. We then investigated the temporal changes in the spatial distributions of hypocenters and Taxis azimuths of focal mechanisms. The distributions of aftershock hypocenters and Taxis azimuths are basically temporally stable, except those in limited portions in the shallow layer near the western edge of the aftershock area, where rapid decrease of aftershocks with Taxis azimuths of WSW to west was observed. If fluid rises from the lower crust due to fault rupture, the locations of aftershocks and focal mechanisms may change over time, especially in the deepest part of the aftershock region. However, the temporal change in these parameters was not apparent at depth. These observations suggest that the aftershock activity of the Central Tottori Prefecture earthquake was controlled mainly by stress concentration rather than strength reduction due to high fluid pressure.

No abstract

Hemizygous mottled brindled mice (Mobr/y mice) were treated by subcutaneous injection of copper and were decapitated on postnatal day 14. Cytochrome c oxidase (COX) activity of the brain mitochondria in the mice given 10 micrograms of copper/g on day 4 or 7 showed significant increases compared with that of untreated Mobr/y animals, and these mice had no neurological symptoms. Mice given 10 micrograms of copper/g on day 12 showed neither increases in COX activity nor clinical improvement. The brain levels of copper, noradrenaline, and dopamine in the mice treated on day 12 were the same as those in animals treated on day 4 or 7. The in vitro activities of dopamine-beta-hydroxylase of the brain were also the same among the treated mice, irrespective of the date of treatment. The results indicate that delays in copper treatment produce irreversible changes in COX activity of the brain and lead to clinical unresponsiveness to treatment.

To study the roles of eosinophils and catecholamines in the pathophysiology of exercise-induced asthma (EIA), an exercise challenge test was performed in 22 asthmatic children, using a bicycle ergometer, and the changes in lung function, plasma norepinephrine (NE), epinephrine (E) and eosinophil cationic protein (ECP) levels with exercise were evaluated. Subjects were classified into three groups from the results of lung function test, respectively: EIA-negative group. EIA-positive groups with good recovery and poor recovery. Eosinophil counts before exercise in the EIA-positive groups were significantly higher than those in the EIA-negative group. The ECP levels rose with exercise in all groups. Five minutes after exercise, ECP values fell to the pre-exercise level in the EIA-negative group, but rose to higher levels in EIA-positive groups. Plasma E levels rose with exercise and showed 4-fold increase in the EIA-negative group, whereas only 1.5-fold increase of plasma E levels was observed in the EIA-positive group with poor recovery. From these findings, a possible contribution of sympathoadrenal hypofunction and a probable involvement of eosinophils in the pathophysiology of EIA have been suggested.