RESUMO
Macrophages in the lungs are the most important cell type supporting replication of Mycobacterium tuberculosis in humans. The objective of this study was to investigate whether the effect of moxifloxacin against M. tuberculosis residing in macrophages could be improved by encapsulation of the drug in the biodegradable nanoparticles, which are known to accumulate in macrophages upon intravenous administration. To accomplish this, moxifloxacin was encapsulated in poly(butyl cyanoacrylate) (PBCA) nanoparticles. Encapsulated moxifloxacin accumulated in macrophages approximately three-fold times more efficiently than the free drug, and was detected in the cells for at least six times longer than free moxifloxacin at the same extracellular concentration. Inhibition of intracellular M. tuberculosis growth with encapsulated moxifloxacin was achieved at the concentration of 0.1microg/ml, whereas the same effect with free MX required a concentration of 1microg/ml. Nanoparticles observed within the macrophage cytoplasm were distributed throughout the cytoplasm, sometimes in the vicinity of intracellular bacteria.
Assuntos
Antituberculosos/química , Compostos Aza/química , Mycobacterium tuberculosis/efeitos dos fármacos , Nanopartículas/química , Quinolinas/química , Antituberculosos/administração & dosagem , Compostos Aza/administração & dosagem , Bacillus subtilis/efeitos dos fármacos , Bioensaio , Células Cultivadas , Composição de Medicamentos , Embucrilato/química , Fluoroquinolonas , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Moxifloxacina , Tamanho da Partícula , Quinolinas/administração & dosagem , Rodaminas , SuspensõesRESUMO
During one menstrual cycle, each of eleven volunteer student nurses at Northwick Park Hospital recorded their vaginal temperature on waking and noted the clock time. Waking times varied between 0530 hours and 1100 hours. Regression analysis revealed significant linear relation between temperature and time of waking, with a slope of 0.086 degrees C/hour (SE, 0.009 degrees C/hr) in the postmenstrual (hypothermal) phase. A rounded adjustment factor of 0.1 degrees C/hour is shown to improve the interpretability of basal body temperature (BBT) charts in a group of seven women regularly using natural family planning methods. The adjustment factor is simple to apply and only involves counting one square on a BBT chart for each hour that the waking time differs from normal.