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141.
Justyna Jarczak Ewa M. KościuczukPaweł Lisowski Nina StrzałkowskaArtur Jóźwik Jarosław HorbańczukJózef Krzyżewski Lech ZwierzchowskiEmilia Bagnicka 《Human immunology》2013
The widespread use of antibiotics has contributed to a huge increase in the number of resistant bacteria. New classes of drugs are therefore being developed of which defensins are a potential source. Defensins are a group of antimicrobial peptides found in different living organisms, involved in the first line of defense in their innate immune response against pathogens. This review summarizes the results of studies of this family of human antimicrobial peptides (AMPs). There is a special emphasis on describing the entire group and individual peptides, history of their discovery, their functions and expression sites. The results of the recent studies on the use of the biologically active peptides in human medicine are also presented. The pharmaceutical potential of human defensins cannot be ignored, especially considering their strong antimicrobial activity and properties such as low molecular weight, reduced immunogenicity, broad activity spectrum and resistance to proteolysis, but there are still many challenges and questions regarding the possibilities of their practical application. 相似文献
142.
B J Taiwo E O Akinkunmi NO Omisore 《African journal of traditional, complementary, and alternative medicines》2013,10(6):528-531
The leaves of Ritchiea capparoides var. longipedicellata (Capparidaceae) is used in ethnomedicine in South-Western Nigeria to treat infectious and parasitic diseases. This study was aimed at identifying the compound(s) that are responsible for the antimicrobial and antiplasmodial activities of the leaves and also to contribute to the chemistry of the plant species. A 70 % aqueous ethanolic extract of the leaves of R. longipedicellata was subjected to repeated liquid chromatographic methods on silica gel, Lobar RP-18 column and Sephadex LH-20 to isolate a Draggendorf positive compound. The compound was identified by 1H and 13C NMR, ultra-violet spectroscopy and polarimetry. The antimicrobial activity of the compound was evaluated using the microbroth dilution method while the antiplasmodial activity was carried out according to Trager and Jenson (1976). The minimum inhibitory concentration (MIC) was expressed in mg/ml. The isolated compound, leavoisomer of stachydrine, inhibited the growth of Escherichia coli NCTC 8196 and Staphylococcus aureus NCTC 6571 at the MIC of 5 mg/ml. In the anti-malaria assay, the compound had inhibitory activity with the concentration required to cause 100% lethality being 0.667 mg/ml.Conclusion: The antibacterial and antiparasitic effects of quaternary ammonium compounds are well documented. However, this study is the first report of the presence and biological activities of this compound in this plant species which may justify the ethnomedicinal uses of the leaves. 相似文献
143.
The free radical copolymerization of 2-thienylmethyl 4-vinylbenzyl ether (TMVBE) with 2-oxo-2-(2-thienylmethoxy)ethyl-2-methylacrylate (TMOEM) has been carried out in 1,4-dioxane at 65?°C?±?1 and were analyzed by Fourier transform infrared, 1H NMR, and 13C NMR spectroscopy. 1H NMR analysis was used to determine the molar fractions of TMVBE and TMOEM in the copolymers. The monomer reactivity ratios were calculated according to the general copolymerization equation using Kelen–Tüdõs and Finemann–Ross linearization methods. The reactivity ratios indicated a tendency toward alternation copolymerization. The thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa and Kissinger methods with a Shimadzu TGA 60 thermogravimetric analysis thermobalance. All the products showed moderate activity against different strains of bacteria and fungi. 相似文献
144.
This work reports on the fabrication and modification of electrospun polymer free silica nanofibers (SiO2 NFs) with the aim of creating heterogeneous antibacterial catalysts. The optical and photophysical properties of the obtained NFs i.e. bare SiO2, Ag-SiO2, Pc-SiO2 and Pc@Ag-SiO2 NFs (Pc = phthalocyanine) were compared and reported. The singlet oxygen quantum yields of the Pc-SiO2 and Pc@Ag-SiO2 NFs were also quantified and found to be 0.08 and 0.12, respectively, in water. All the modified SiO2 NFs were found to possess photoactivity against S. aureus with the most effective being the Pc@Ag-SiO2 NFs due to the synergy between the Pc and Ag nanoparticles. The bare SiO2 NFs do not exhibit any antibacterial activity while the Ag-SiO2 and Pc@Ag-SiO2 NFs were found to also exhibit dark toxicity. The generated photocatalysts are attractive because they are active against bacteria and they are easily retrievable post-application. The nanocatalysts reported herein are therefore feasible candidates for real-life antibacterial applications. 相似文献
145.
钛及其合金具有稳定的化学性质和良好的人体亲和性,常被作为骨科植入材料,但未经处理的钛植入物易发生骨整合不良和植入物周围感染导致植入失败。近年来,人口老龄化加剧带动植入材料使用量增加,亟需性能更好的钛表面修饰方法以降低植入失败率。理想的骨科植入物应同时具备促成骨和抗菌特性,但目前大量表面改性策略只解决其中一种问题,导致植入物无法达到预期效果。因此,植入材料涂层需满足这两种特性或在两者间寻找平衡点。综述近几年来解决钛植入物无菌性松动或感染问题的最新策略,如表面形貌改善和生物分子涂层等促进成骨,抗菌药物负载和光热治疗等防治感染措施,并通过双因素整合和三因素整合进一步介绍了同时解决这两个问题的研究进展。 相似文献
146.
Hyunjoo Oh Sang Taek Heo Misun Kim Young Ree Kim Jeong Rae Yoo 《Yonsei medical journal》2021,62(4):306
PurposeStreptococcus pneumoniae (S. pneumoniae) causes respiratory tract infections. Its non-vaccine serotypes and multidrug-resistant pneumococcal diseases have increased during the post-pneumococcal vaccination era. Therefore, it is important to understand the regional and age-related antimicrobial susceptibility of S. pneumoniae to select appropriate empirical antimicrobials.Materials and MethodsWe retrospectively studied trends in the antimicrobial resistance of S. pneumoniae to commonly prescribed antibiotics in patient groups of various ages at a single teaching hospital in Jeju Island from 2009 to 2018.ResultsIn total, 1460 S. pneumoniae isolates were obtained during the study period. The overall antimicrobial resistance rates of S. pneumoniae to penicillin, erythromycin, ceftriaxone, levofloxacin, and vancomycin were 16.2%, 84.7%, 25.9%, 3.3%, and 0.0%, respectively, and the MDR rate was 6.7%. Erythromycin and ceftriaxone resistance rates increased by years; however, they were significantly reduced in adult groups. Levofloxacin resistance and MDR rates were also higher in adult groups. Overall, the MDR rate significantly increased during the recent 10 years, as well as in patients with a history of hospitalization within 90 days [odds ratio (OR)=3.58, 95% confidence interval (CI)=1.91–6.71] and sinusitis (OR=4.98, 95% CI=2.07–11.96).ConclusionErythromycin and ceftriaxone resistance rates and the MDR rate of S. pneumoniae significantly increased during the recent 10 years; the trends in individual antimicrobial resistance rates significantly differed between the age groups. This study indicates the need for caution when using ceftriaxone as an empirical antimicrobial against pneumococcal infections. 相似文献
147.
148.
Eli E. Machtei Georgios Romanos Philip Kang Suncica Travan Stephan Schmidt Evangelos Papathanasiou Nikolaos Tatarakis Moshik Tandlich Leila H. Liberman Jacob Horwitz Seyed Hossein Bassir Srinivas Myneni Harlan J. Shiau Lior Shapira Nikos Donos Athena Papas Joerg Meyle William V. Giannobile Panos N. Papapanou David M. Kim 《Journal of periodontology》2021,92(1):11-20
149.
Y.-T. Lee S.-C. Kuo S.-P. Yang Y.-T. Lin D.-H. Chiang F.-C. Tseng T.-L. Chen C.-P. Fung 《Clinical microbiology and infection》2013,19(7):640-645
The phenotypically indistinguishable Acinetobacter baumannii and Acinetobacter nosocomialis have become leading pathogens causing nosocomial pneumonia in critically ill patients. A. baumannii and A. nosocomialis nosocomial pneumonias were grouped as a single clinical entity previously. This study aimed to determine whether they are the same or a different clinical entity. A total of 121 patients with A. baumannii and 131 with A. nosocomialis bacteremic nosocomial pneumonia were included during an 8-year period. Despite the similar Charlson co-morbidity scores at admission, patients with A. baumannii pneumonia were more likely to have abnormal haematological findings, lobar pneumonia, significantly higher Acute Physiology and Chronic Health Evaluation II scores and higher frequency of shock at the onset of bacteraemia than those with A. nosocomialis pneumoni. A. baumannii isolates were resistant to more classes of antimicrobials, except colistin, and therefore the patients with A. baumannii pneumonia were more likely to receive inappropriate antimicrobial therapy. The 14-day mortality was significantly higher in patients with A. baumannii pneumonia (34.7% vs. 15.3%, p 0.001). A. baumannii was an independent risk factor for mortality (OR, 2.03; 95% CI, 1.05–3.90; p 0.035) in the overall cohort after adjustment for other risk factors for death, including inappropriate antimicrobial therapy. The results demonstrated the difference in clinical presentation, microbial characteristics and outcomes between A. baumannii and A. nosocomialis nosocomial pneumonia, and supported that they are two distinct clinical entities. 相似文献
150.