Increasing resistance to antibiotics of Pseudomonas aeruginosa leads to therapeutic deadlock and alternative therapies are needed. We aimed to evaluate the effects of Lactobacillus clinical isolates ...in vivo, through intranasal administration on a murine model of Pseudomonas aeruginosa pneumonia. We screened in vitro 50 pulmonary clinical isolates of Lactobacillus for their ability to decrease the synthesis of two QS dependent-virulence factors (elastase and pyocyanin) produced by Pseudomonas aeruginosa strain PAO1. These results demonstrate that intranasal priming with lactobacilli acts as a prophylaxis, and avoids fatal complications caused by Pseudomonas aeruginosa pneumonia in mice. These results were independent of in vitro anti-Pseudomonas aeruginosa activity on QS-dependent virulence factors. Further experiments are required to identify the immune mechanism before initiating clinical trials.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mycobacterium abscessus, as a species, has been increasingly implicated in respiratory infections, notably in cystic fibrosis patients. The species comprises 3 subspecies, which can be difficult to ...identify. Since they differ in antibiotic susceptibility and clinical relevance, developing a routine diagnostic tool discriminating Mycobacterium abscessus at the subspecies level is a real challenge. Forty-three Mycobacterium abscessus species isolates, previously identified by multilocus sequence typing, were analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). A subspecies identification algorithm, based on five discriminating peaks, was drawn up and validated by blind identification of a further 49 strains, 94% of which (n = 46) were correctly identified. Two M. abscessus subsp. massiliense strains were misidentified as M. abscessus subsp. abscessus, and for 1 other strain identification failed. Inter- and intralaboratory reproducibility tests were conclusive. This study presents, for the first time, a classification algorithm for MALDI-TOF MS identification of the 3 M. abscessus subspecies. MALDI-TOF MS proved effective in discriminating within the M. abscessus species and might be easily integrated into the workflow of microbiology labs.
From January to December 2007, 973 stool specimens were prospectively collected from children hospitalized for gastroenteritis signs or from neonates and premature cases who were born in two French ...hospital settings in the north of France. They were tested by rapid enzyme immunoassay (EIA) analyses for rotavirus and adenovirus and by two commercially available ELISA tests for the detection of norovirus and astrovirus. The overall rates of prevalence for rotavirus, norovirus, adenovirus, and astrovirus were 21, 13, 5, and 1.8%, respectively, and they did not significantly differ between the two hospital settings (P = 0.12). Mixed virus infections were detected in 32 (3.3%) of the 973 study children and were associated with norovirus in 21 (66%) infants, including 5 premature cases. From fall to spring, norovirus infections accounted for 52% of documented gastroenteritidis viral infections at a time when rotavirus was epidemic, resulting in mixed norovirus and rotavirus gastrointestinal tract infections. Of the 367 documented viral gastroenteritis cases, 15 (4.1%) were identified as nosocomial infections, 5 of which occurred in premature cases. These findings highlight the need to implement norovirus and astrovirus ELISA detection assays in association with rapid EIA rotavirus and adenovirus detection assays for the clinical diagnosis and the nosocomial prevention of gastroenteritis viral infections in pediatric departments.
Point-of-care syndromic PCR (POC SPCR) assays are useful tools for the rapid detection of the most common causative agents of community-acquired infections responsible for meningitis and encephalitis ...infections. We evaluated the performance characteristics of the new QIAstat-Dx
Meningitis/Encephalitis panel (QS) compared to the laboratory reference methods and the POC SPCR Biofire
FilmArray
Meningitis Encephalitis Panel (FA). Viral (Enterovirus, Parechovirus, HSV-1, HSV-2, HHV-6, VZV) and bacterial (
K1,
,
, encapsulated
,
,
,
,
) pathogens were suspended at low concentrations and tested with the POC SPCR systems. The reproducibility, analytical specificity, carryover contamination, interferences and clinical samples were evaluated. All samples tested positive with both QS and FA except for those containing the lowest concentrations of Enterovirus-D68-B3, Echovirus-30 and
which were only detected by FA. In terms of analytical specificity, we observed 3 false positive results out of 48 QS tests versus 1 out of 37 FA tests. For the other studied criteria, both QS and FA performed as expected. Our results suggest that the performance characteristics of QS are close to those of FA. A prospective multicenter study would be useful to complete the performances evaluation of QS.
For health professionals, repeated SARS‐CoV‐2 RNA detection through PCR combined with properly validated serologic assays for the presence of anti‐IgM and anti‐IgG antibodies should be mandatory.
For ...health professionals, repeated SARS‐CoV‐2 RNA detection through PCR combined with properly validated serologic assays for the presence of anti‐IgM and anti‐IgG antibodies should be mandatory.
The emergence of new strains in RNA viruses is mainly due to mutations or intra and inter-genotype homologous recombination. Non-homologous recombinations may be deleterious and are rarely detected. ...In previous studies, we identified HCV-1b strains bearing two tandemly repeated V3 regions in the NS5A gene without ORF disruption. This polymorphism may be associated with an unfavorable course of liver disease and possibly involved in liver carcinogenesis. Here we aimed at characterizing the origin of these mutant strains and identifying the evolutionary mechanism on which the V3 duplication relies.
Direct sequencing of the entire NS5A and E1 genes was performed on 27 mutant strains. Quasispecies analyses in consecutive samples were also performed by cloning and sequencing the NS5A gene for all mutant and wild strains. We analyzed the mutant and wild-type sequence polymorphisms using Bayesian methods to infer the evolutionary history of and the molecular mechanism leading to the duplication-like event.
Quasispecies were entirely composed of exclusively mutant or wild-type strains respectively. Mutant quasispecies were found to have been present since contamination and had persisted for at least 10 years. This V3 duplication-like event appears to have resulted from non-homologous recombination between HCV-1b wild-type strains around 100 years ago. The association between increased liver disease severity and these HCV-1b mutants may explain their persistence in chronically infected patients.
These results emphasize the possible consequences of non-homologous recombination in the emergence and severity of new viral diseases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Acute cytomegalovirus (CMV) infection in immunocompetent patients is common worldwide, with seroprevalence rates of 40%–100%, depending on the country, socioeconomic conditions, and the patient's ...age. Infection is most often asymptomatic, but acute cytomegalovirus infection is occasionally revealed by prolonged fever, cervical lymphadenitis, and arthralgia, and it is more rarely revealed by pneumonia, myocarditis, pericarditis, colitis, and hemolytic anemia. Here, we report 2 cases of acute CMV infection in nonimmunocompromised adults that were complicated by venous thrombosis with pulmonary embolism. We also review previously reported cases of vascular thrombosis and discuss the propensity of CMV to induce vascular damage with associated thrombosis.
A fatal case of enterovirus 71 infection with pulmonary edema and rhombencephalitis occurred in Brest, France, in April 2007. The virus was identified as subgenogroup C2. This highly neurotropic ...enterovirus merits specific surveillance outside the Asia-Pacific region.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK