External synchronization of two dynamical systems with uncertain parameters

External synchronization is addressed as two or more dynamical systems with synchronous motions, which is also regarded as master-slave system. In this paper, two dynamical systems, one employs a hysteretic term to model the friction phenomenon, the other involves a hardening stiffness component with the third order of displacement due to flexible deformation, are controlled to converge to the same trajectory. The control strategy is extended from feedback control for all parameters known to adaptive contro...     

Effects of 18-hydroxydeoxycorticosterone on central nervous system excitability

The effects of 18-hydroxydeoxycorticosterone (18-OH-DOC) on central nervous system excitability were studied in adrenalectomized rats. Sixty-four evoked potentials (EP) recorded from the pontine reticular formation were averaged before and after the injection of vehicle and hormone. 750 micrograms of 18-OH-DOC dissolved in 0.5 ml of a 4:1 saline Cremophor-EL solution were injected i.v. A decrease of 55.7 +/- 6.1% in the amplitude of the EPs was observed with the hormone 16.3 min +/- 2.7 (SE) after injection. Amplitude values returned to baseline levels 38 min +/- 6.8 (SE) after injection. The secretion of 18-OH-DOC is greatly increased by ACTH and might modulate central nervous system function.     

Effects of 18-hydroxydeoxycorticosterone on central nervous system excitability

Summary The effects of 18-hydroxydeoxycorticosterone (18-OH-DOC) on central nervous system excitability were studied in adrenalectomized rats. Sixty-four evoked potentials (EP) recorded from the pontine reticular formation were averaged before and after the injection of vehicle and hormone. 750 g of 18-OH-DOC dissolved in 0.5 ml of a 41 saline Cremophor-EL solution were injected i.v. A decrease of 55.7±6.1% in the amplitude of the EPs was observed with the hormone 16.3 min±2.7 (SE) after injection. Amplitude values returned to baseline levels 38 min±6.8 (SE) after injection. The secretion of 18-OH-DOC is greatly increased by ACTH and might modulate central nervous system function.     

In vitro metabolism of progesterone by the adrenals of spontaneously hypertensive rats

Zusammenfassung Der Einbau des¹⁴C-Progesterons in Corticosteroide bei Nebennierensegmenten von Wistar-Ratten mit spontaner Hypertonie unterscheidet sich in nichts vom Einbau bei Nebennieren der Kontrollratten, was im Gegensatz zu Befunden mit regenerierten Nebennieren steht. Eine kausale Beziehung zwischen Nebennierenrindenfunktion und spontanem Hochdruck scheint ausgeschlossen zu sein.

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Dr. M. K.Birmingham is a Medical Research Associate of the Medical Research Council of Canada. This work was supported by grants from the Medical Research Council of Canada and the 33rd Degree Scottish Rite Committee for Research in Dementia Praecox. The authors thank Dr. R. A.Cleghorn for his interest in this project.     

Listeriolysin O allows Listeria monocytogenes replication in macrophage vacuoles

Listeria monocytogenes is an intracellular bacterial pathogen that replicates rapidly in the cytosol of host cells during acute infection. Surprisingly, these bacteria were found to occupy vacuoles in liver granuloma macrophages during persistent infection of severe combined immunodeficient (SCID) mice. Here we show that L. monocytogenes can replicate in vacuoles within macrophages. In livers of SCID mice infected for 21 days, we observed bacteria in large LAMP1(+) compartments that we termed spacious Listeria-containing phagosomes (SLAPs). SLAPs were also observed in vitro, and were found to be non-acidic and non-degradative compartments that are generated in an autophagy-dependent manner. The replication rate of bacteria in SLAPs was found to be reduced compared to the rate of those in the cytosol. Listeriolysin O (LLO, encoded by hly), a pore-forming toxin essential for L. monocytogenes virulence, was necessary and sufficient for SLAP formation. A L. monocytogenes mutant with low LLO expression was impaired for phagosome escape but replicated slowly in SLAPs over a 72 h period. Therefore, our studies reveal a role for LLO in promoting L. monocytogenes replication in vacuoles and suggest a mechanism by which this pathogen can establish persistent infection in host macrophages.     

Nuclear localization of aldosterone in rat brain cells assessed by autoradiography.

Autoradiographic studies with 3H aldosterone demonstrate nuclear concentration of hormone in neurons of the hippocampus, septum, allocortical regions and brain stem reticular formation and motor nuclei of cranial nerves and in the meninges. The results suggest that mineralocorticoids have wide ranging effects on different parts of the central nervous system.