Alojamiento para los refugiados que llegan a Grecia, 2015-2017

Las llegadas masivas a Grecia desde 2015 han superado con creces la provisión de alojamiento aceptable. Los intentos para ofrecer soluciones continúan

IncHI plasmids, a dynamic link between resistance and pathogenicity

Plasmids of incompatibility group (Inc) HI1 are important vectors of antibiotic resistance in both of the major causal agents of enteric fever: Salmonella enterica subspecies enterica serovar Typhi and S. Paratyphi A. In S. Typhi, IncHI1 plasmids appeared in the 1970s and spread globally. In some circumstances they are maintained within the bacterial population even in the absence of selection from antibiotics. The low cost associated with IncH plasmids in Salmonella is due, in part, to the presence of a plasmid gene encoding an H-NS-like global regulator which acts co-operatively with chromosomally encoded H-NS. Very recently, IncHI1 plasmids have crossed from S. Typhi into S. Paratyphi A; the acquisition of drug resistance and possibly other phenotypic traits encoded by IncHI1 plasmids has increased the virulence potential of this neglected pathogen. There is no vaccine for S. Paratyphi A and resistance to the current drugs of choice, the fluoroquinolones, is also spreading rapidly. There is a conserved backbone to all IncH plasmids but variation occurs in regions of the plasmids associated with antibiotic resistance. These IncHI1 plasmids are allowing major human pathogens to sample genes available in their environment, the human gut, and will be maintained by enhancing the competitive advantage of the bacterial host. Therefore competition between closely related resistance plasmids will probably increase the transmission of enteric fever by enhancing the fitness of their bacterial hosts

Genetic markers in s. Paratyphi c reveal primary adaptation to pigs

Salmonella enterica with the identical antigenic formula 6,7:c:1,5 can be differentiated biochemically and by disease syndrome. One grouping, Salmonella Paratyphi C, is currently considered a typhoidal serovar, responsible for enteric fever in humans. The human-restricted typhoidal serovars (S. Typhi and Paratyphi A, B and C) typically display high levels of genome degradation and are cited as an example of convergent evolution for host adaptation in humans. However, S. Paratyphi C presents a different clinical picture to S. Typhi/Paratyphi A, in a patient group with predisposition, raising the possibility that its natural history is different, and that infection is invasive salmonellosis rather than enteric fever. Using whole genome sequencing and metabolic pathway analysis, we compared the genomes of 17 S. Paratyphi C strains to other members of the 6,7:c:1,5 group and to two typhoidal serovars: S. Typhi and Paratyphi A. The genome degradation observed in S. Paratyphi C was much lower than S. Typhi/Paratyphi A, but similar to the other 6,7:c:1,5 strains. Genomic and metabolic comparisons revealed little to no overlap between S. Paratyphi C and the other typhoidal serovars, arguing against convergent evolution and instead providing evidence of a primary adaptation to pigs in accordance with the 6,7:c:1.5 strains

John Wain, Remarks on the short story

The short story is, of course, sui generis; it is not an unsatisfactory form of the long story. It is a form on its own, with its own laws and its own logic. A short story has its natural length. It isn’t trying to do the same thing as a novel. It has ground staked out which is its own ground. Historically, it is not an ancient form. It’s very much a modern form. It belongs to modern literature, the literature of about the last hundred years. It comes into being at about the same time as the ..

Using next generation sequencing to tackle non-typhoidal Salmonella infections.

The publication of studies using next generation sequencing to analyse large numbers of bacterial isolates from global epidemics is transforming microbiology, epidemiology and public health. The emergence of multidrug resistant Salmonella Typhimurium ST313 is one example. While the epidemiology in Africa appears to be human-to-human spread and the association with invasive disease almost absolute, more needs to be done to exclude the possibility of animal reservoirs and to transfer the ability to track all Salmonella infections to the laboratories in the front line. In this mini-review we summarise what is currently known about non-typhoidal Salmonella in sub-Saharan Africa and discuss some of the issues which remain

Identification and characterisation of enteroaggregative Escherichia coli subtypes associated with human disease

Enteroaggregative E. coli (EAEC) are a major cause of diarrhoea worldwide. Due to their heterogeneity and carriage in healthy individuals, identification of diagnostic virulence markers for pathogenic strains has been difficult. In this study, we have determined phenotypic and genotypic differences between EAEC strains of sequence types (STs) epidemiologically associated with asymptomatic carriage (ST31) and diarrhoeal disease (ST40). ST40 strains demonstrated significantly enhanced intestinal adherence, biofilm formation, and pro-inflammatory interleukin-8 secretion compared with ST31 isolates. This was independent of whether strains were derived from diarrhoea patients or healthy controls. Whole genome sequencing revealed differences in putative virulence genes encoding aggregative adherence fimbriae, E. coli common pilus, flagellin and EAEC heat-stable enterotoxin 1. Our results indicate that ST40 strains have a higher intrinsic potential of human pathogenesis due to a specific combination of virulence-related factors which promote host cell colonization and inflammation. These findings may contribute to the development of genotypic and/or phenotypic markers for EAEC strains of high virulence

Use of Vitex doniana (black plum) and Abutilon hirtum (Florida keys) extracts as an integral part of phytomedicine in tackling multidrug-resistant Salmonella

Introduction: The high prevalence and global spread of antibiotic resistance is driving the search for new antibacterial agents. Screening small molecules against specific bacterial targets has not yielded new compounds therefore functional assays and phenotypic screens are now being used. In Nigeria, drug resistance towards Salmonella is a major public health concern. Methodology: Nine fully characterized clinical Salmonella isolates, from the Department of Medical Microbiology, Jos University Teaching Hospital, Plateau State, Nigeria, were screened by broth microdilution for susceptibility to fractionated ethanol extracts of Vitex doniana and Abutilon hirtum. This was compared to the control organism ATCC25922 and a range antibiotics: CH (chloramphenicol), SP (sparfloxacin), AM (amoxicillin), CN (gentamicin), S (streptomycin), PEF (pefloxacin). Results: The most common resistance profile was AM,CN,S with most isolates susceptible to fluoroquinolones. Activity was detected from both plant extracts with MICs of extracted fractions ranging from 150 - 300 µg/mL. Interestingly both plants produced extracts with bactericidal activity from 300 - 600 µg/mL. V. doniana exhibited better activity against the resistant Salmonella strains in terms of greater inhibition zones, but A. hirtum extracts were more consistently active against all isolates. In comparison with the synthetic drugs, both plant extracts exhibited activity against more isolates – this activity was bactericidal. Conclusions: Nigeria needs better anti-salmonella products and these results represent a starting point for antibiotic drug discovery

A novel broadly applicable PCR-RFLP method for rapid identification and subtyping of H58 Salmonella Typhi

Salmonella Typhi (S. Typhi), the human-adapted agent of typhoid fever, is genetically monomorphic. SNPs accumulation divided the S. Typhi population in 85 haplotypes (H) of which one, H58, has undergone a clonal expansion. The surveillance of H58 S. Typhi is particularly important, especially in areas where typhoid fever is endemic. We developed a simple PCR and PCR-RFLP method to detect and subtype H58 S. Typhi based on the presence of genomic deletion and specific SNPs. The method was validated against 39 S. Typhi isolates of known haplotype, showing 100% of specificity and high sensitivity, and then used to screen a collection of 99 S. Typhi from Asia, demonstrating a high incidence of H58 S. Typhi in Jordan and India. Our method is designed to be applied in all laboratories with basic molecular biology equipment and few financial resources and allows the surveillance of H58 S. Typhi in resource poor settings

Postpneumonectomy syndrome: Surgical management and long-term results

ObjectivePostpneumonectomy syndrome is a rare syndrome of dynamic airway obstruction caused by extreme rotation and shift of the mediastinum after pneumonectomy, resulting in symptomatic central airway compression. We have treated this syndrome by mediastinal repositioning and placement of saline-filled prostheses into the pneumonectomy space. There is a paucity of outcome data for patients treated surgically, with only a single series of 11 patients previously reported. We analyzed our recent experience with treatment of this syndrome and report on the short and long-term outcomes and quality of life assessment of the largest series ever reported of patients treated by mediastinal repositioning.MethodsRecords were reviewed of all patients who underwent mediastinal repositioning for postpneumonectomy syndrome between January of 1992 and June of 2006. Long-term health-related quality of life was assessed by administration of the Saint George's Respiratory Questionnaire.ResultsThere were 18 patients (15 women and 3 men) with a median age of 44 years (range 14–67 years). Thirteen patients had undergone right pneumonectomy, and 5 patients had undergone left pneumonectomy. None of the patients in whom postpneumonectomy syndrome developed after left pneumonectomy had a right-sided aortic arch. Five patients had undergone pneumonectomy in childhood (age < 13 years). The median interval between pneumonectomy and mediastinal repositioning was 7.5 years (range 1.1–54.8 years). The median follow-up was 32 months (range 4–143 months). The operative mortality was 5.6% (1/18). Complications occurred in 5 patients (27.8%): pneumonia in 3 patients and acute respiratory distress syndrome in 2 patients. The median hospitalization was 6 days (range 3–155 days). Some 77% (10/13) of patients reported significant improvement in their breathing and overall state of health after surgery; 15.4% of patients (2/13) were somewhat better, and 7.7% of patients (1/13) had no improvement. No patients' condition was worse after surgery. All patients who reported improvement in their symptoms after surgery remained symptomatically improved at the time of the quality of life assessment. Some 92.3% (12/13) were not at all or only slightly limited in their social activities because of breathing problems, and 84.6% (11/13) were not at all or only slightly limited in their ability to work as a result of their physical health.ConclusionRepositioning of the mediastinum with placement of prostheses for postpneumonectomy syndrome can be performed with low mortality and morbidity. Surgical repositioning provides immediate and lasting symptomatic relief to patients in whom postpneumonectomy syndrome develops

Salmonella nomenclature in the genomic era: a time for change

Salmonella enterica nomenclature has evolved over the past one hundred years into a highly sophisticated naming convention based on the recognition of antigens by specific antibodies. This serotyping scheme has led to the definition of over 2500 serovars which are well understood, have standing in nomenclature and, for the majority, biological relevance. Therefore, it is highly desirable for any change in naming convention to maintain backwards compatibility with the information linked to these serovars. The routine use of whole genome sequencing and the well-established link between sequence types and serovars presents an opportunity to update the scheme by incorporating the phylogenetically relevant sequence data whilst preserving the best of serotyping nomenclature. Advantages include: overcoming the variability in antibody preparations; removing the need to use laboratory animals and implementing a truly universal system. However, the issue of trying to reproduce the phenotyping gold standard needs to be relaxed if we are to fully embrace the genomic era. We have used whole genome sequence data from over 46,000 isolates of Salmonella enterica subspecies enterica to define clusters in two stages: Multi Locus Sequence Typing followed by antigen prediction. Sequence type—serotype discrepancies were resolved using core SNP clustering to determine the phylogenetic groups and this was confirmed by overlaying the antigenic prediction onto the core SNP clusters and testing the separation of clusters using cgMLST Hierarchical Clustering. This allowed us to define any major antigenic clusters within an ST—here called the MAC type and written as ST-serovar. Using this method, 99.96% of Salmonella isolates reported in the UK were assigned a MAC type and linked to a serovar name taken from the Kauffmann and White scheme. We propose a change for reporting of Salmonella enterica sub-types using the ST followed by serovar