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41.
The aim of this study was to identify the factors determining the incidence of Lyme borreliosis (LB) in south‐western Poland by estimating the prevalence of B. burgdorferi s. l. in I. ricinus, and to analyze the temporal abundance of ticks in relation to epidemiological data on LB incidence. Host‐seeking ticks collected in 2011 in four districts in southwestern Poland were examined by nested PCR for the presence of B. burgdorferi s.l. In total, 2,507 host‐seeking I. ricinus were collected. The temporal abundance of ticks varied between districts. The minimal infection rates with B. burgdorferi s.l. were 11.5% for nymphs and 37.7% for adults. There were no statistical differences in the level of infection between districts either for nymphs or for adults. Five different genospecies were identified within the B. burgdorferi s.l. complex: B. garinii, B. afzelii, B. lusitaniae, B. valasiana, and B. burgdorferi s.s., and additionally B. miyamotoi. Our results point to a relationship between tick temporal abundance and LB incidence both for adults and nymphs. The high abundance of ticks is positively correlated with the number of LB cases in humans. The tick's abundance may be considered as a major factor in determining the LB risk in southwestern Poland.  相似文献   
42.
In this study, a series of novel 3-(substituted phenyl)-6,7-dimethoxy-3a,4-dihydro-3H-indeno[1,2-c]isoxazole analogues were synthesized and evaluated for antimycobacterial activity against Mycobacterium tuberculosis (MTB) H37Rv and isoniazid resistant M. tuberculosis (INHR-MTB). All the newly synthesized compounds were showing moderate to high inhibitory activities. The compound 6,7-dimethoxy-3-(4-chloro phenyl)-4H-indeno[1,2-c]isoxazole (4b) was found to be the most promising compound, active against MTB H37Rv and INHR-MTB with minimum inhibitory concentrations of 0.22 and 0.34 μM.  相似文献   
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The increasing clinical importance of drug-resistant mycobacterial pathogens has lent additional urgency to microbiological research and new antimycobacterial compound development. For this purpose, new triazoles were synthesized and evaluated for antituberculosis activity. A series of 4-arylidenamino-4H-1,2,4-triazole-3-thiol derivatives (2a–n) were synthesized from the treatment of 4-amino-4H-1,2,4-triazoles-3-thiol (1) with the respective aldehydes and were evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv (ATCC 27294), using the BACTEC 460 radiometric system and BACTEC 12B medium. Compound 2k showed an intereting activity at 6.25 μg/mL with a 87 percentage inhibition.  相似文献   
44.
A series of halogenated sulfanilamides and halogenated benzolamide derivatives have been investigated as inhibitors of three β-carbonic anhydrases (CAs, EC 4.2.1.1) from the bacterial pathogen Mycobacterium tuberculosis, mtCA 1 (Rv1284), mtCA 2 (Rv3588c) and mtCA 3 (Rv3273). All three enzymes were inhibited with efficacies between the submicromolar to the micromolar one, depending on the substitution pattern at the sulfanilamide moiety/fragment of the molecule. Best inhibitors were the halogenated benzolamides (KIs in the range of 0.12–0.45 μM) whereas the halogenated sulfanilamides were slightly less inhibitory (KIs in the range of 0.41–4.74 μM). This class of β-CA inhibitors may have the potential for developing antimycobacterial agents with a diverse mechanism of action compared to the clinically used drugs for which many strains exhibit multi-drug/extensive multi-drug resistance.  相似文献   
45.
The seasonality of respiratory diseases (common cold, influenza, etc.) is a well-known phenomenon studied from ancient times. The development of predictive models is still not only an actual unsolved problem of mathematical epidemiology but also is very important for safety of public health. Here we show that SIRS (Susceptible-Infected-Recovered-Susceptible) model accurately enough reproduces real curves of flu activity. It contains variable reaction rate, which is a function of mean daily temperature.The proposed alternation of variables represents SIRS equations as the second-order ODE with an outer excitation. It reveals an origin of such predictive efficiency and explains analytically the 1:1 dynamical resonance, which is known as a crucial property of epidemic behavior. Our work opens the perspectives for the development of instant short-time prediction of a normal level of flu activity based on the weather forecast, and allows to estimate a current epidemic level more precisely. The latter fact is based on the explicit difference between the expected weather-based activity and instant anomalies.  相似文献   
46.
《Biomarkers》2013,18(7):523-528
Inflammation has been identified as an important factor for disease exacerbation in obstructive lung disease. In this study, we used neutrophil and eosinophil counts as biomarkers for exacerbation in obstructive lung disease. We conducted a case–control study within a cohort of patients frequenting an outpatient clinic of Respiratory Medicine using data from the Utrecht Patient Oriented Database (UPOD). Cases were patients with a hospital admission for obstructive lung disease in 2005. For each case, one control patient was sampled from the same study base. We identified 143 cases (118 patients with chronic obstructive pulmonary disease and 25 asthma patients) and 143 controls. Admission was associated with both neutrophilia (adjusted odds ratio (OR) 4.3; 95% confidence interval (CI) 2.2–8.5), and eosinophilia (adjusted OR 2.6; 95% CI 1.1–6.2). The association with eosinophilia was only seen in asthma patients. In conclusion, neutrophil and eosinophil counts seem to be useful biomarkers for identifying exacerbations in pharmacoepidemiological studies on obstructive lung disease.  相似文献   
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