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Bo Zhen Jia-Wen Hu Jia-Jia Wang Meng-Jiao Shi Li Li 《Journal of Asian natural products research》2019,21(5):409-418
Seven natural compounds, including new compounds hyperascyrins L-N (1-3) and four known compounds (4-7), were acquired from the aerial parts of Hypericum ascyron, that were all identified as methylated polycyclic polyprenylated acylphloroglucinol derivatives (mPPAPs). The structures of these compounds were established by NMR spectroscopy, experimental and calculated electronic circular dichroism (ECD) data. The neuroprotective activities and hepatoprotective activity of these compounds (10 µM) were evaluated. Compounds 1, 2 and 3 exhibited neuroprotection activity. Compounds 1 and 3 show hepatoprotective activity. 相似文献
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This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.
The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same. 相似文献
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《Arab Journal Of Gastroenterology》2019,20(2):74-80
Background and study aimsDiarrhoea and urinary tract infection (UTI) are common clinical problems. Meanwhile, Escherichia coli (E. coli), is the commonest bacterial pathogen reported in both of them. This study aimed to evaluate the pathogenic E. coli (PEC) in stool of acute diarrhoea and urine of UTI regarding their virulence genes and their influence on the susceptibility to routinely prescribed antibiotics.Patients and methodsTwenty two stool and another 22 urine samples of patients with acute diarrhoea and UTI respectively were collected from patients admitted at Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt. E. coli isolation, identification of their phyla; chuA, yjaA, and TspE4.C2, and further identification of 10 virulent genes; fimH, papC, papG//, papG///, papEF, afa, sfa, CNF1, iroN & hlyA was performed. Antibiotic susceptibility was studied against quinolones, gentamicin (GM), and trimethoprim-sulphamethoxazole (TMP-SMX).ResultsThe studied virulence genes were comparably detected in both pathogenic samples. In diarrheogenic E. coli (DEC); phylum A was significantly related to both ciprofloxacin (CIP) and TMP-SMX resistance, and both of the virulence genes fimH and iroN were significantly related to all the studied antibiotics resistance, while afa was significantly related to nalidixic acid (NA) resistance. In uropathogenic E. coli (UEC); phylum D was significantly related to CIP and levofloxacin resistance, and both of the virulence genes fimH and iroN were significantly related to most of the studied antibiotics resistance.ConclusionThe isolated PEC was evidently and broadly resistant to the studied antibiotics, with limited influence of their phyla and virulence genes (fimH and iroN). 相似文献
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BackgroundA greater proportion of HCV-infected people who inject drugs (PWID) need to be linked to care for HCV antiviral treatment. This study sets out to evaluate the efficacy of contingency management (CM) for improving HCV linkage to care, treatment initiation, adherence, and cure for PWID recruited from a needle and syringe program.MethodsBetween March 2015 and April 2016, 20 participants were enrolled into the CM arm, and then subsequently enrolled 20 participants in the enhanced standard of care (eSOC) arm. Participants in the eSOC arm received an expedited appointment and a round-trip transit card. Participants enrolled in the CM arm received eSOC plus $25 for up to ten HCV clinical visits and $10 for each returned weekly medication blister pack. Adherence was measured via electronic blister packs.ResultsOverall the median age was 47 years; most were men (67%) and Hispanic (69%). There were no significant differences in demographic characteristics between participants in the study arms. In the CM arm 74% were linked to HCV care, compared to 30% in the eSOC arm (p = 0.01). In the CM arm, 75% (9/12) of treatment eligible participants initiated treatment, compared to 100%(4/4) in the eSOC arm (p = 0.53). All patients (9/9) achieved cure in the CM arm, as compared to 75% (3/4) of patients in the eSOC arm. There were no differences in adherence between study arms.ConclusionsIn this pilot study, contingency management led to higher rates of HCV linkage to care for PWID, as compared to standard of care. CM should be considered as a possible intervention to improve the HCV treatment cascade for PWID. 相似文献