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Crosby Ware posted an update 6 hours, 24 minutes ago
We identified four proxy indicators estimating antibiotic prescribing appropriateness in dental care. All proxy indicators had good clinimetric properties. Performance scores were generally low (10.5 to 73.0%, depending on the indicator), suggesting an important room for improvement. These results showed large variations between dentists (large interquartile ranges) and according to the patients’ characteristics (case-mix stability).Conclusion – These four proxy indicators might be used to guide antibiotic stewardship interventions in dental care.Cyp51 contribution to azole resistance has been broadly studied and characterized in Aspergillus fumigatus, whereas it remains poorly investigated in other clinically relevant species of the genus, such as those of section Nigri In this work, we aimed to analyze the impact of cyp51 genes (cyp51A and cyp51B) on the voriconazole (VRC) response and resistance of Aspergillus niger and Aspergillus tubingensis We generated CRISPR-Cas9 cyp51A and cyp51B knock-out mutants from strains with different genetic backgrounds and diverse patterns of azole susceptibility. Single gene deletions of cyp51 genes resulted in 2 to 16-fold decrease of the VRC Minimum Inhibitory Concentration (MIC) values, which were below the VRC Epidemiological Cutoff Value (ECV) established by the Clinical and Laboratory Standards Institute (CLSI) irrespective of their parental strains susceptibilities. Gene expression studies in the tested species confirmed that cyp51A participates more actively than cyp51B in the transcriptional response of azole stress. However, ergosterol quantification revealed that both enzymes comparably impact the total ergosterol content within the cell, as basal and VRC-induced changes to ergosterol content was similar in all cases. These data contribute to our understanding on Aspergillus azole resistance, especially in non-fumigatus species.The use of colistin as a last resort antimicrobial is compromised by the emergence of resistant enterobacteria with acquired determinants like mcr genes, mutations that activate the PmrAB system and by still unknown mechanisms. This work analyzed 74 E. coli isolates from healthy swine, turkey or bovine, characterizing their colistin resistance determinants. The mcr-1 gene, detected in 69 isolates, was the main determinant found among which 45% were carried by highly mobile plasmids, followed by four strains lacking previously known resistance determinants or two with mcr-4 (one in addition to mcr-1), whose phenotypes were not transferred by conjugation. Although a fraction of isolates carrying mcr-1 or mcr-4 genes also presented missense polymorphisms in pmrA or pmrB, constitutive activation of PmrAB was not detected, in contrast to strains with mutations that confer colistin resistance. The expression of mcr genes negatively controls the transcription of the arnBCADTEF operon itself, a down-regulation that was also observed in the four isolates lacking known resistance determinants, three of them sharing the same macrorestriction and plasmid profiles. Genomic sequencing of one of these strains, isolated from a bovine in 2015, revealed a IncFII plasmid of 62.1 Kb encoding an extra copy of the arnBCADTEF operon closely related to Kluyvera ascorbata homologs. This element, called pArnT1, was cured by ethidium bromide and the cells lost resistance to colistin in parallel. Furthermore, a susceptible E. coli strain acquired heteroresistance after transformation with pArnT1 or pBAD24 carrying the Kluyvera-like arnBCADTEF operon, revealing it as a new colistin resistance determinant.We have designed, synthesized, and characterized a library of 38 novel flavonoid compounds linked with amines. Some of these amine-linked flavonoids have potent in vitro activity against parasites that cause cutaneous leishmaniasis, a tropical disease endemic in 80 countries worldwide. The most promising candidate, FM09h, was highly active with IC50 of 0.3 μM against L. amazonensis, L. tropica and L. braziliensis amastigotes. It was metabolically stable (39% and 66% of FM09h remaining after 30-minute incubation with human and rat liver microsomes respectively). In L. amazonensis LV78 cutaneous leishmaniasis mouse model, intralesional injection of FM09h (10 mg/kg, once every 4 days for 8 times) demonstrated promising effect in reducing the footpad lesion thickness by 72%, displaying an efficacy comparable to SSG (63%).We evaluated the in vitro activity of rifamycin derivatives, including rifampin, rifapentine, rifaximin, and rifabutin, against clinical nontuberculous mycobacteria (NTM) isolates. this website Of the rifamycin derivatives, rifabutin showed the lowest MICs against all NTM species, including Mycobacterium avium complex, M. abscessus, and M. kansasii Rifabutin also had effective in vitro activity against macrolide- and aminoglycoside-resistant NTM isolates. Rifabutin could be worth considering as a therapeutic option for NTM disease, particularly drug-resistant disease.Most deaths from severe falciparum malaria occur within 24 h of presentation to a hospital. Intravenous (i.v.) artesunate is the first-line treatment for severe falciparum malaria, but its efficacy may be compromised by delayed parasitological responses. In patients with severe malaria, the life-saving benefit of the artemisinin derivatives is their ability to clear circulating parasites rapidly, before they can sequester and obstruct the microcirculation. To evaluate the dosing of i.v. artesunate for the treatment of artemisinin-sensitive and reduced ring stage sensitivity to artemisinin severe falciparum malaria infections, Bayesian pharmacokinetic-pharmacodynamic modeling of data from 94 patients with severe malaria (80 children from Africa and 14 adults from Southeast Asia) was performed. Assuming that delayed parasite clearance reflects a loss of ring stage sensitivity to artemisinin derivatives, the median (95% credible interval) percentage of patients clearing ≥99% of parasites within 24 h (PC24≥99%) for standard (2.4 mg/kg body weight i.v. artesunate at 0 and 12 h) and simplified (4 mg/kg i.v. artesunate at 0 h) regimens was 65% (52.5% to 74.5%) versus 44% (25% to 61.5%) for adults, 62% (51.5% to 74.5%) versus 39% (20.5% to 58.5%) for larger children (≥20 kg), and 60% (48.5% to 70%) versus 36% (20% to 53.5%) for smaller children ( less then 20 kg). The upper limit of the credible intervals for all regimens was below a PC24≥99% of 80%, a threshold achieved on average in clinical studies of severe falciparum malaria infections. In severe falciparum malaria caused by parasites with reduced ring stage susceptibility to artemisinin, parasite clearance is predicted to be slower with both the currently recommended and proposed simplified i.v. artesunate dosing regimens.