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The efficacies of the new quinolones temafloxacin, ofloxacin, and ciprofloxacin were investigated against Mycoplasma pneumoniae in an experimental hamster pneumonia model. Hamsters were infected intratracheally with M. pneumoniae and sacrificed 18 h after the final medication, and their lungs were aseptically removed, homogenized, and cultured quantitatively. The efficacies of these drugs were determined by the CFU of M. pneumoniae in lungs. Temafloxacin and ofloxacin, but not ciprofloxacin, were active when the oral administration of200 mg/kg ofbody weight per day (once per day) for 5 days was initiated 24 h after infection. Although no effect on the elimination of M. pneumoniae was observed after the administration of these drugs at 200 mg/kg/day at 5 days after infection, the continuous administration for 15 days of temafloxacin, but not ofloxacin or ciprofloxacin, significantly reduced viable M. pneumoniae in the lungs. These results suggest that temafloxacin and ofloxacin are effective in the acute phase of infection and, moreover, that temafloxacin is effective in the late stage of infection during which progressive lung alterations and continuous increases in mycoplasmal growth occurred. The peak levels of temafloxacin in sera and lungs after oral administration were similar to those of ofloxacin and higher than those of ciprofloxacin. The areas under the curve of temafloxacin in the lung tissue, however, were higher than those of ofloxacin and ciprofloxacin. On the basis of these results, temafloxacin and ofloxacin might be promising antimicrobial agents for the treatment of mycoplasmal infection.Mycoplasma pneumoniae is the causative agent of upper respiratory tract infections and pneumonia in humans and the experimental pneumonia of hamsters (3,5,8,10). Macrolide and tetracycline antibiotics have been widely used in chemotherapy against M. pneumoniae infections because of the susceptibility of the infectious agent to these antibiotics (1,4,13,17,23). At the same time, the reported incidences of mutants resistant to erythromycin from patients treated with or without the antibiotics have increased (14,15).Recently, the efficacy of new quinolones against various respiratory pathogens, including M. pneumoniae, has been demonstrated (4,16,22). We have also reported that temafloxacin, ofloxacin, and ciprofloxacin, among several new quinolones, possess more mycoplasmacidal activity against M. pneumoniae than macrolide and tetracycline antibiotics. In this report, we evaluated the in vivo potency of new quinolones, administered orally against M. pneumoniae pneumonia in hamsters, which exhibited the potent mycoplasmacidal activity in vitro described previously (1). MATERIALS AND METHODSM. pneumoniae. M. pneumoniae 242, freshly isolated from the throat swab of a patient with mycoplasma pneumonia and passaged five to seven times in broth, was used as the challenge strain. Culture samples were kept at -80°C until used for inoculation. The MICs of temafloxacin, ofloxacin, and ciprofloxacin for the strain were 1.56,...

We investigated the capability of an L-form derived from Staphylococcus aureus to induce tumor necrosis factor alpha (TNF-ax) production in murine peritoneal macrophages. The activity for TNF-a induction was found in the membrane fraction of the L-form but not in the cytoplasmal fraction purified by the sucrose step gradient centrifugation. TNF-at mRNA was also detected in macrophages stimulated with L-form membranes. L-form induced TNF-a production in macrophages from both lipopolysaccharide-responsive and-unresponsive mouse strains. Regardless of the presence of polymyxin B, the activity of TNF-ai induction of L-form was mostly found in the phenol layer, but not in the aqueous layer, both of which were prepared by phenol extraction method. Fractions of L-form membranes representing molecular masses of approximately between 29 and 36 kDa were primarily responsible for inducing the production of TNF-aI consistently. Moreover, this stimulatory effect was abolished by digestion with Streptomyces griseus protease. In Western blot (immunoblot) analysis with anti-lipoteichoic acid antibody, two bands (65 and 45 kDa) were observed in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the phenol layer, whereas one band (14 kDa) was observed in either the aqueous layer or lipoteichoic acid of S. aureus. These results suggest that the component in the membrane of the L-form, distinct from cell wall components such as teichoic acid or lipopolysaccharide, possesses the capability to stimulate TNF-a production by macrophages.

Optimization of spatial resource allocation is crucial for the successful control of invasive species under a limited budget but requires labor-intensive surveys to estimate population parameters. In this study, we devised a novel framework for the spatially explicit optimization of capture effort allocation using state-space population models from past capture records. We applied it to a control program for invasive snapping turtles to determine effort allocation strategies that minimize the population density over the whole area. We found that spatially heterogeneous density dependence and capture pressure limit the abundance of snapping turtles. Optimal effort allocation effectively improved the control effect, but the degree of improvement varied substantially depending on the total effort. The degree of improvement by the spatial optimization of allocation effort was only 3.21% when the total effort was maintained at the 2016 level. However, when the total effort was increased by 2, 4, and 8 times, spatial optimization resulted in improvements of 4.65%, 8.33%, and 20.35%, respectively. To achieve the management goal for snapping turtles in our study area, increasing the current total effort by more than 4 times was necessary, in addition to optimizing the spatial effort. The snapping turtle population is expected to reach the target density one year after the optimal management strategy is implemented, and this rapid response can be explained by high population growth rate coupled with density-dependent feedback regulation. Our results demonstrated that combining a state-space model with optimization makes it possible to adaptively improve the management of invasive species and decision-making. The method used in this study, based on removal records from an invasive management program, can be easily applied to monitoring data for wildlife and pest control management using traps in a variety of ecosystems.