The selection of an appropriate non-hazardous solvent or solvent system is essential to determine the rheological properties and electrospinnability of the solution, the productivity, and the ...morphology of nanofibres. In this study, poly lactic acid (PLA) solutions were prepared in various pure solvents and binary-solvent systems to investigate the effect of different solution properties on nanofibre morphology and diameter. Viscosity, conductivity and surface tension of each solution were measured. Nanofibre morphology was observed by scanning electron microscopy (SEM). Of all the solvent systems used acetone/dimethylformamide gave the highest fibre productivity and finest defect-free nanofibres. Therefore this solvent system was studied in more detail, varying the solvent ratio. Also the polymer concentration in this solvent system was varied to investigate the effect on nanofibre morphology and solution properties. Morphological investigations were done in correlation with rheological measurements: beaded nanofibrous structures were collected from solutions with concentration around the critical chain entanglement concentration (Ce), while defect-free nanofibres were produced when the concentration was increased to about twice the entanglement concentration. Further investigation of the effect of the PLA concentration on the elastic (G′) and the plastic (G″) moduli showed a sudden increase of the elastic moduli (G′) at the critical chain entanglement concentration. The results showed that the solvent properties, boiling point, viscosity, conductivity and surface tension, have a significant effect on process productivity, morphology and diameter distribution of the PLA nanofibres.
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•Acetone/dimethylformamide as new suitable solvent system for PLA nanofibres.•Solvent boiling point exerts a strong effect on nanofibre morphology and diameter.•Relationship C–η was weaker for the unentangled regime compared to other results.•Relationship C–η was in agreement for the entangled regime.
Colistin-resistant/carbapenem-resistant Acinetobacter baumannii is a significant challenge for antibiotic treatment and infection control policies. Since 2012, in Central Greece an increase of ...colistin/pan- resistant A. baumannii has occurred, indicating the need for further analysis.
A total of 86 colistin-resistant/carbapenem-resistant out of 1228 A. baumannii clinical isolates, consecutively collected between 2012 and 2014 in a tertiary Greek hospital of Central Greece, as well as one environmental isolate from surveillance cultures were studied. Molecular typing and mechanisms of resistance to colistin and to carbapenems were assessed, whereas, epidemiological and clinical data of the patients were reviewed.
During the study period, the rate of colistin resistance gradually increased and reached 21.1 % in 2014. All colistin-resistant/carbapenem-resistant A. baumannii belonged to 3LST ST101 clone that corresponds to the international clonal lineage II. Carbapenem resistance was associated with the presence of bla oxa-23-like, while resistance to colistin probably correlated with G54E and R109H amino acid substitutions in PmrA and PmrC, respectively.
Epidemiological data of the patients indicated that the first detection of colistin-resistant/carbapenem-resistant ST101 clone in the University Hospital of Larissa (UHL) was associated with a patient who previously had received colistin, while, the movement of the infected patients into the hospital probably resulted to its spread.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary Background Fusarium spp. can cause disseminated infections, particularly in immunocompromised patients. Fusarium verticillioides is a human pathogen, and sporadic cases of fusariosis have ...been reported. Aim To report a nosocomial cluster of F. verticillioides bloodstream infections among seven immunocompetent inpatients following reconstruction works. Methods Identification was performed using macroscopic and microscopic morphology, and molecular assays (sequencing the nuclear ribosomal internal transcribed spacer region and translation elongation factor-1α gene). Susceptibility testing was performed in accordance with the guidelines of the Clinical and Laboratory Standards Institute. Environmental surveillance specimens were taken and cultured on Sabouraud dextrose agar plates. Findings In total, 16 blood cultures obtained from the seven patients were positive for F. verticillioides . All surveillance cultures were negative. Conclusions In order to prevent fungaemia, it is important to implement effective infection control measures, before, during and after demolition and construction activities in healthcare settings.
The results of the study reported here are part of an ongoing integrated research programme aimed at producing additional, robust, evidence on the genetic resistance to classical scrapie in goats, ...with particular reference to codon 146. The study targeted animals aged 56 years, which were born and raised in infected herds and were being culled for management reasons. A total of 556 animals were tested, and all positive animals (n = 117) were of the susceptible NN genotype. A total of 246 goats heterozygous or homozygous for putatively resistant alleles (S146 and D146) were screened with no positive results. The outcome of this study supports the hypothesis that the D146 and S146 alleles could be used as the basis for a nationwide strategy for breeding for resistance in the Cypriot goat population.
The study's objective is to quantify in vivo epicardial force and strain in the normal and transgenic myocardium using microsensors. Male mice (n = 39), including C57BL/6 (n = 26), 129/Sv (n = 5), ...wild-type (WT) C57 × 129Sv (n = 5), and muscle LIM protein (MLP) knock-out (n = 3), were studied under 1.5% isoflurane anaesthesia. Microsurgery allowed the placement of two piezoelectric crystals at longitudinal epicardial loci at the basal, middle, and apical LV regions, and the independent (and/or concurrent) placement of a cantilever force sensor. The findings demonstrate longitudinal contractile and relaxation strains that ranged between 4.8-9.3% in the basal, middle, and apical regions of C57BL/6 mice, and in the mid-ventricular regions of 129/Sv, WT, and MLP mice. Measured forces ranged between 3.1-8.9 mN. The technique's feasibility is also demonstrated in normal mice following afterload, occlusion-reperfusion challenges. Furthermore, the total mid-ventricular forces developed in MLP mice were significantly reduced compared to the WT controls (5.9 ± 0.4 versus 8.9 ± 0.2 mN, p < 0.0001), possibly owing to the fibrotic and stiffer myocardium. No significant strain differences were noted between WT and MLP mice. The possibility of quantifying in vivo force and strain from the normal murine heart is demonstrated with a potential usefulness in the characterisation of transgenic and diseased mice, where regional myocardial function may be significantly altered.
Previous studies have shown the association between the polymorphisms serine (S) or aspartic acid (D) at codon 146 of the PRNP gene and resistance to scrapie. All goats aged >12 months (a total of ...1075 animals) from four herds with the highest prevalence of scrapie in the country were culled and tested, of which 234 (21·7%) were positive by either the rapid test or immunohistochemistry (IHC) for any of the tissues tested. The odds of scrapie infection occurring in NN146 goats was 101 95% credible interval (CrI) 19–2938 times higher than for non-NN146 or unknown genotypes. IHC applied to lymphoreticular tissue produced the highest sensitivity (94%, 95% CrI 90–97). The presence of putatively resistant non-NN146 alleles in the Cypriot goat population, severely affected by scrapie, provides a potential tool to reduce/eradicate scrapie provided that coordinated nationwide breeding programmes are implemented and maintained over time.
We evaluated the diagnostic yield of open-lung biopsies (OLBs) in a large tertiary cancer center to determine the role of infectious diseases as causes of undiagnosed pulmonary lesions. All ...consecutive adult patients with either single or multiple pulmonary nodules or masses who underwent a diagnostic OLB over a period of 10 years (1998–2007) were retrospectively identified. Their risk factors for malignancy and clinical and radiological characteristics were reviewed, and their postoperative complications were assessed. We evaluated 155 patients with a median age of 57 years (range, 19–83 years). We identified infectious etiologies in 29 patients (19 %). The most common diagnosis in this group was histoplasmosis (12 41 %), followed by nontuberculous mycobacterial infection (7 24 %) and aspergillosis (4 14 %). The majority of the 126 remaining patients had nonmalignant diagnoses, the most prevalent being nonspecific granuloma (26 %), whereas only 17 % had malignant diagnoses. We observed no significant differences among the patients with infectious, malignant, or both noninfectious and nonmalignant final diagnoses regarding their demographic, laboratory, and clinical characteristics. Six percent of the patients had at least one post-OLB complication, and the post-OLB mortality rate was 1 %. OLB is a safe diagnostic procedure which frequently identifies a wide variety of infectious and inflammatory diseases.
Summary
Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a chronic incurable infection of intestinal tract of animals. Molecular characterization of Map isolates ...classifies them into two major groups, ‘Cattle’ or Type II and ‘Sheep’ or Type I/III with a different phenotype, epidemiology, virulence and pathogenesis. The aim of this study was to examine 192 Map ELISA‐positive sheep and goats from Cyprus using faecal culture and genotype Map isolates using IS1311 PCR and restriction endonuclease analysis (IS1311 PCR‐REA) with HinfI restriction enzyme. Map was isolated from only four (4.6%) faecal samples out of 88 sheep and 15 (14.4%) faecal samples out of 104 goats. Genotyping of the isolates using IS1311 PCR‐REA revealed that sheep and goat populations on the island are infected primarily by ‘Sheep’ strains. Only three Map isolates from goats originated from one farm were characterized as ‘Cattle’ strains.
Summary
Background Development of organ‐ and non‐organ‐specific autoantibodies has been reported in hepatitis C virus patients treated with interferon‐α plus/minus ribavirin.
Aims To address ...whether prevalence and the titre of gastric parietal autoantibodies and non‐organ‐specific autoantibody in hepatitis C virus‐treated patients were affected by therapy, and if the development of these antibodies carries any clinical significance on the response to treatment, as few studies in adults have been strictly designed to address the above hypothesis.
Methods Samples at three time‐points (baseline, end of treatment, end of follow‐up) from 102 hepatitis C virus patients (39 sustained responders, 26 relapsers, 33 non‐responders; four lost in follow‐up) were studied for gastric parietal autoantibodies and/or non‐organ‐specific autoantibody by indirect immunofluorescence, commercial and in‐house enzyme‐linked immunosorbent assays.
Results Sustained virological and biochemical response was associated with antinuclear antibody absence (end of treatment or end of follow‐up), decrease of smooth‐muscle antibody titres during therapy and gastric parietal autoantibodies negativity at baseline. However, after multivariate analysis only antinuclear antibody positivity at the end of treatment and increase of smooth‐muscle antibody titres were associated with worst treatment response, independently of known factors of worst treatment outcome.
Conclusions We were able to demonstrate a negative correlation between the efficacy of anti‐viral treatment for hepatitis C virus and the presence of antinuclear antibody and smooth‐muscle antibody before treatment, or their increase during therapy.
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