Detection and functional role of local gradients of H+-ions on the intracellular mitochondrial membrane with covalently linked pH-probe

The study is devoted to the registration of local H+ gradients on the inner membrane of mitochondria under conditions of H+ pump functioning were recorded. By using a covalently linked pH probe (fluorescein isothiocyanate), a local increase in the activity of hydrogen ions on the outer face of the inner mitochondrial membrane in the presence of the respiration substrate at increased permeability of the membrane for K+ was registered. It was also found that the buffer capacity of medium affects the respiration rate of completely uncoupled mitochondria; a change in respiration rate strictly correlates with changes in local H+ gradients on the mitochondrial membrane. It was concluded that local gradients of H+ activity can control the rate of functioning of H+ pumps. It was shown that, under certain conditions, the system of H+ pumps incorporated into succinate oxidase of mitochondria functions as a nonliner system.     

The leading routes and factors in the transmission of the causative agent of campylobacteriosis under current conditions]

Epidemiological investigations carried out at the foci of Campylobacter infection in Moscow and the Moscow region in 1987-1990 demonstrated that Campylobacter infection was recently registered as sporadic cases in a few foci. The alimentary route of the transmission of this infection was the main factor of its spread. A high role of everyday contacts in the spread of this infection was noted. The possibility for outbreaks and sporadic cases of Campylobacter infection to be masked by very frequently occurring associations of these bacteria is discussed.     

Sensitivity of the pathogen of Campylobacter infection to various antibiotics]

Antibiotic sensitivity of 21 Campylobacter strains isolated from humans, monkeys and birds with diarrhea was assayed and the findings are presented. It was shown that all the isolates were highly sensitive to ofloxacin, pefloxacin, ciprofloxacin, josamycin, pipemidinic acid and amoxyclav (a combination of amoxycillin and clavulanic acid). The predominating majority of the strains were resistant to rifampicin, amoxycillin and phosphomycin. The majority of the cultures were sensitive to erythromycin and roxithromycin while some of the isolates were resistant to them which could be used as an additional biological characteristic of Campylobacter cultures and considered in choosing agents for antibiotic therapy.