Search results for "microbial"
showing 10 items of 2041 documents
High temperature and bacteriophages can indirectly select for bacterial pathogenicity in environmental reservoirs
2010
The coincidental evolution hypothesis predicts that traits connected to bacterial pathogenicity could be indirectly selected outside the host as a correlated response to abiotic environmental conditions or different biotic species interactions. To investigate this, an opportunistic bacterial pathogen, Serratia marcescens, was cultured in the absence and presence of the lytic bacteriophage PPV (Podoviridae) at 25°C and 37°C for four weeks (N = 5). At the end, we measured changes in bacterial phage-resistance and potential virulence traits, and determined the pathogenicity of all bacterial selection lines in the Parasemia plantaginis insect model in vivo. Selection at 37°C increased bacterial…
Irrigants in endodontics: A review
2019
Aim. The purpose of this paper was to review different endodontic irrigants use in endodontics. Background. Many areas inside the canals are inaccessible to mechanical instrumentation, the presence of lateral and accessory canals makes root canal preparation even more difficult. The complete smear layer removal from the root canals depends consequently on both the irrigant solutions and the instrumentation phase. Review consults. Irrigants play a very important role in disinfecting the root canals thus the use of specific solutions has been performed in conjunction with mechanical instrumentation for many years. Combination of several irrigants can increase the capability to penetrate insid…
Phytoplankton in extreme environments: importance and consequences of habitat permanency
2020
AbstractThere is hardly any sunshine exposed surface on this Earth, be it water or terrain, which would not support some biota. Still, many habitats offer harsh conditions requiring specialized physiological adaptations to survive. These environments are referred to as extremes; often inhabited by extremophilic organisms. In this review, characteristic species and assemblage properties of phytoplankton inhabiting extreme environments (especially lakes and pools where planktic life is potentially possible and independently of their origin) in terms of alkalinity, acidity, DOC, salinity, temperature, light and mixing regime will be outlined. Lakes characterized by more than a single extreme a…
Low incidence of Vibrio vulnificus among Vibrio isolates from sea water and shellfish of the western Mediterranean coast.
1999
A specific search for Vibrio vulnificus in natural marine samples from the Spanish Mediterranean Sea was carried out by nested PCR and cultural approaches using thiosulphate-citrate-bile salts-sucrose agar (TCBS) and cellobiose-polymixin B-colistin agar (CPC), incubated at 40 degrees C, as selective media. Presumptive colonies were identified by PCR using specific primers against 23S rRNA sequences. This species was isolated from sea water and edible bivalves, mainly after preenrichment in alkaline peptone water (APW) at 40 degrees C followed by CPC agar. None of the V. vulnificus isolates identified corresponded to serovar E. Dominant Vibrio species on directly inoculated TCBS plates incub…
Chemical composition and antimicrobial activity of the essential oils of some species of Anthemis sect. Anthemis (Asteraceae) from Sicily
2017
The chemical composition of the essential oils isolated from the aerial parts of Anthemis arvensis L. subsp. arvensis, Anthemis cretica subsp. messanensis (Brullo) Giardina & Raimondo and from flowers and leaves of Anthemis cretica subsp. columnae (Ten.) Frezén were determinated by GC–FID and GC–MS analyses. Torreyol (85.4%) was recognised as the main constituent of the Anthemis arvensis subsp. arvensis essential oil, while in the essential oils of Anthemis cretica subsp. messanensis, collected on the rock and cultivated in Hortus Botanicus Panormitanus, (E)-chrysanthenyl acetate (28.8 and 24.2% resp.), 14-hydroxy-α-humulene (8.1 and 5.3% resp.), santolina triene (8 and 5.8% resp.) and …
Emergence of Aspergillus fumigatus azole resistance in azole-naïve patients with chronic obstructive pulmonary disease and their homes.
2017
Azole-resistant Aspergillus fumigatus (ARAF) has been reported in patients with chronic obstructive pulmonary disease (COPD) but has not been specifically assessed so far. Here, we evaluated ARAF prevalence in azole-naïve COPD patients and their homes, and assessed whether CYP51A mutations were similar in clinical and environmental reservoirs. Sixty respiratory samples from 41 COPD patients with acute exacerbation and environmental samples from 36 of these patient's homes were prospectively collected. A. fumigatus was detected in respiratory samples from 11 of 41 patients (27%) and in 15 of 36 domiciles (42%). Cyp51A sequencing and selection on itraconazole medium of clinical (n = 68) and e…
Antimicrobial Lessons From a Large Observational Cohort on Intra-abdominal Infections in Intensive Care Units
2021
Severe intra-abdominal infection commonly requires intensive care. Mortality is high and is mainly determined by disease-specific characteristics, i.e. setting of infection onset, anatomical barrier disruption, and severity of disease expression. Recent observations revealed that antimicrobial resistance appears equally common in community-acquired and late-onset hospital-acquired infection. This challenges basic principles in anti-infective therapy guidelines, including the paradigm that pathogens involved in community-acquired infection are covered by standard empiric antimicrobial regimens, and second, the concept of nosocomial acquisition as the main driver for resistance involvement. I…
Thiazoles, Their Benzofused Systems, and Thiazolidinone Derivatives: Versatile and Promising Tools to Combat Antibiotic Resistance.
2020
Thiazoles, their benzofused systems, and thiazolidinone derivatives are widely recognized as nuclei of great value for obtaining molecules with various biological activities, including analgesic, anti-inflammatory, anti-HIV, antidiabetic, antitumor, and antimicrobial. In particular, in the past decade, many compounds bearing these heterocycles have been studied for their promising antibacterial properties due to their action on different microbial targets. Here we assess the recent development of this class of compounds to address mechanisms underlying antibiotic resistance at both bacterial-cell and community levels (biofilms). We also explore the SAR and the prospective clinical applicati…
In vitro activity of fluconazole, voriconazole and caspofungin against clinical yeast isolates.
2007
Predicting the clinical outcome of a systemic mycosis is often a difficult task, especially when microbiological resistance is one of the factors contributing to therapeutic failure. Some of these factors are host-related--e.g. immune state, site and severity of infection, poor compliance to therapy--while others are associated with the drug's characteristics--e.g. dosage, type of compound (fungistatic/fungicidal), pharmacokinetic properties and drug-drug interactions. In the last few years, clinicians have been confronted with the problem of selecting the most appropriate antifungal therapy for systemic infections and have highlighted the need for a reliable method to assay the in vitro su…
In vitro activities of antimicrobial agents against Candida species
1999
Objective. Antimicrobial mouthrinses may represent a valid alternative to topical antifungal agents. However, the action of antimicrobials could be affected by the different ingredients incorporated into mouthrinse products. The purpose of the present study was to investigate the in vitro antifungal and fungicidal activities of antimicrobials alone. Study Design. A broth macrodilution method was used to determine the minimum inhibitory concentration of 4 antimicrobial agents against Candida species. Minimum fungicidal concentration was also determined. Results. All antimicrobials showed antifungal activity against all tested organisms, but cetylpyridinium chloride received significantly low…