H111 is an opportunistic pathogen associated with chronic lung infections in cystic fibrosis patients. Biofilm formation, motility and virulence of
are regulated by the second messenger cyclic ...di-guanosine monophosphate (c-di-GMP). In the present study, we analyzed the role of all 25 putative c-di-GMP metabolizing proteins of
H111 with respect to motility, colony morphology, pellicle formation, biofilm formation, and virulence. We found that RpfR is a key regulator of c-di-GMP signaling in
, affecting a broad spectrum of phenotypes under various environmental conditions. In addition, we identified Bcal2449 as a regulator of
virulence in
larvae. While Bcal2449 consists of protein domains that may catalyze both c-di-GMP synthesis and degradation, only the latter was essential for larvae killing, suggesting that a decreased c-di-GMP level mediated by the Bcal2449 protein is required for virulence of
. Finally, our work suggests that some individual proteins play a role in regulating exclusively motility (CdpA), biofilm formation (Bcam1160) or both (Bcam2836).
is an important opportunistic pathogen with the potential to develop resistance against last-line antibiotics, such as carbapenems, limiting the treatment options. Here, we investigated the ...antibiotic resistance profiles of 10
strains isolated from patient samples in the intensive-care unit of a Brazilian tertiary hospital using conventional PCR and a comprehensive genomic characterization of a specific
strain (CRK317) carrying both the
and
genes simultaneously. All isolates were completely resistant to β-lactam antibiotics, including ertapenem, imipenem, and meropenem with differencing levels of resistance to aminoglycosides, quinolones, and tigecycline also observed. Half of the strains studied were classified as multidrug-resistant. The carbapenemase-producing isolates carried many genes of interest including: β-lactams (
,
,
,
group,
group and
in 20-80% of the strains), aminoglycoside resistance genes
and
(
, 70 and 80%, a fluoroquinolone resistance gene (
, 80%), a sulfonamide resistance gene (
, 80%) and a multidrug efflux system transporter (
, 70%) while all strains carried the efflux pumps
(subunit A) and
. Moreover, we performed a comprehensive genomic characterization of a specific
strain (CRK317) carrying both the
and
genes simultaneously. The draft genome assembly of the CRK317 had a total length of 5,462,831 bp and a GC content of 54.8%. The chromosome was found to contain many essential genes.
analysis identified many genes associated with resistance phenotypes, including β-lactamases (
,
,
,
,
,
), the bleomycin resistance gene (
), an erythromycin resistance methylase (
), aminoglycoside-modifying enzymes
-
,
-
,
, a sulfonamide resistance enzyme (
), a chloramphenicol acetyltransferase (
like), a plasmid-mediated quinolone resistance protein (
), a glutathione transferase (
), PEtN transferases (
,
) and a glycosyltransferase (
). We also detected 22 genomic islands, eight families of insertion sequences, two putative integrative and conjugative elements with a type IV secretion system, and eight prophage regions. This suggests the significant involvement of these genetic structures in the dissemination of antibiotic resistance. The results of our study show that the emergence of carbapenemase-producing
, co-harboring
and
, is a worrying phenomenon which highlights the importance of developing strategies to detect, prevent, and control the spread of these microorganisms.
Risk of pelvic inflammatory disease associated with
and
is increased after termination of pregnancy (TOP) and may be increased after insertion of intrauterine devices (IUDs). Screening prior to these ...procedures is recommended only for
. We examined
and
prevalence and associated factors among women presenting to a pregnancy termination and contraception service over 10 years.
Retrospective analysis of clinical data collected from 17 573 women aged 15-45 years in 2009-2019 and for 266
.
positive women tested for macrolide resistance-associated mutations in 2016-2019.
and
prevalence was 3.7% and 3.4%, respectively. In multivariable analyses, shared risk factors were younger age (p<0.001, for both
and
), socioeconomic disadvantage (p=0.045 and p=0.008, respectively) and coinfection (p<0.001, for both sexually transmitted infections), with 10.1% of
positive women also positive for
. Additional risk factors were earlier year of visit (p=0.001) for
and for
residing outside a major city (p=0.013). The proportion of
infections tested between 2016 and 2019 with macrolide resistance-associated mutations was 32.7%.
Given the high level of antimicrobial resistance and the prevalence of coinfection, testing
positive women for
could be considered in this setting to prevent further spread of resistant infections. Further research is required into the causal link between
and pelvic inflammatory disease in women undergoing TOP and IUD insertion.
Obliterative bronchiolitis (OB) post-lung transplantation involves IL-17-regulated autoimmunity to type V collagen and alloimmunity, which could be enhanced by complement activation. However, the ...specific role of complement activation in lung allograft pathology, IL-17 production, and OB is unknown. The current study examines the role of complement activation in OB. Complement-regulatory protein (CRP) (CD55, CD46, complement receptor 1-related protein y/CD46) expression was downregulated in human and murine OB; and C3a, a marker of complement activation, was upregulated locally. IL-17 differentially suppressed complement receptor 1-related protein y expression in airway epithelial cells in vitro. Neutralizing IL-17 recovered CRP expression in murine lung allografts and decreased local C3a production. Exogenous C3a enhanced IL-17 production from alloantigen- or autoantigen (type V collagen)-reactive lymphocytes. Systemically neutralizing C5 abrogated the development of OB, reduced acute rejection severity, lowered systemic and local levels of C3a and C5a, recovered CRP expression, and diminished systemic IL-17 and IL-6 levels. These data indicated that OB induction is in part complement dependent due to IL-17-mediated downregulation of CRPs on airway epithelium. C3a and IL-17 are part of a feed-forward loop that may enhance CRP downregulation, suggesting that complement blockade could be a therapeutic strategy for OB.
Although a highly heritable and disabling disease, bipolar disorder's (BD) genetic variants have been challenging to identify. We present new genotype data for 1,190 cases and 401 controls and ...perform a genome-wide association study including additional samples for a total of 2,191 cases and 1,434 controls. We do not detect genome-wide significant associations for individual loci; however, across all SNPs, we show an association between the power to detect effects calculated from a previous genome-wide association study and evidence for replication (P = 1.5×10(-7)). To demonstrate that this result is not likely to be a false positive, we analyze replication rates in a large meta-analysis of height and show that, in a large enough study, associations replicate as a function of power, approaching a linear relationship. Within BD, SNPs near exons exhibit a greater probability of replication, supporting an enrichment of reproducible associations near functional regions of genes. These results indicate that there is likely common genetic variation associated with BD near exons (±10 kb) that could be identified in larger studies and, further, provide a framework for assessing the potential for replication when combining results from multiple studies.
Schizophrenia (SCZ) and bipolar disorder (BD) are highly heritable psychiatric disorders. Associated genetic and gene expression changes have been identified, but many have not been replicated and ...have unknown functions. We identified groups of genes whose expressions varied together, that is co-expression modules, then tested them for association with SCZ. Using weighted gene co-expression network analysis, we show that two modules were differentially expressed in patients versus controls. One, upregulated in cerebral cortex, was enriched with neuron differentiation and neuron development genes, as well as disease genome-wide association study genetic signals; the second, altered in cerebral cortex and cerebellum, was enriched with genes involved in neuron protection functions. The findings were preserved in five expression data sets, including sets from three brain regions, from a different microarray platform, and from BD patients. From those observations, we propose neuron differentiation and development pathways may be involved in etiologies of both SCZ and BD, and neuron protection function participates in pathological process of the diseases.
Lung transplantation, in patients with end-stage lung disease, is limited by chronic rejection, which occurs with an incidence and severity exceeding most other transplanted organs. Alloimmune ...responses play an important role in progression to chronic rejection that manifests as bronchiolitis obliterans syndrome (BOS), but no biomarker can currently predict the progression to BOS. Studies in animal models suggest that intragraft T regulatory cells (Tregs) are important in maintaining transplantation tolerance, and FoxP3 is the protoypic Treg marker.
Leukocytes in blood and bronchoalveolar lavage (BAL) fluid were compared for expression of FoxP3 by flow cytometry in 14 stable lung transplant recipients and 6 lung transplant recipients who eventually developed BOS.
Stable patients, compared with patients who subsequently developed BOS, consistently had a significantly increased percentage of FoxP3 cells among CD4 cells in BAL and greater levels of the Treg-attracting chemokine CCL22. These differences were observed in limited sequential analyses, before, at the time of acute rejection, and postacute rejection. In this pilot study, a threshold of 3.2% CD4/FoxP3 cells in the BAL distinguished stable recipients from those subsequently developing BOS within the first 2 years posttransplantation.
The proportion of FoxP3 cells among CD4 cells in BAL may help to predict lung allograft outcome and guide therapeutic immunosuppression in lung transplant recipients.
Low Ag dose promotes induction and persistence of regulatory T cells (Tregs) in mice, yet few studies have addressed the role of Ag dose in the induction of adaptive CD4(+)FOXP3(+) Tregs in humans. ...To this end, we examined the level of FOXP3 expression in human CD4(+)CD25(-) T cells upon activation with autologous APCs and varying doses of peptide. Ag-specific T cells expressing FOXP3 were identified by flow cytometry using MHC class II tetramer (Tmr). We found an inverse relationship between Ag dose and the frequency of FOXP3(+) cells for both foreign Ag-specific and self Ag-specific T cells. Through studies of FOXP3 locus demethylation and helios expression, we determined that variation in the frequency of Tmr(+)FOXP3(+) T cells was not due to expansion of natural Tregs, but instead, we found that induction, proliferation, and persistence of FOXP3(+) cells was similar in high- and low-dose cultures, whereas proliferation of FOXP3(-) T cells was favored in high Ag dose cultures. The frequency of FOXP3(+) cells positively correlated with suppressive function, indicative of adaptive Treg generation. The frequency of FOXP3(+) cells was maintained with IL-2, but not upon restimulation with Ag. Together, these data suggest that low Ag dose favors the transient generation of human Ag-specific adaptive Tregs over the proliferation of Ag-specific FOXP3(-) effector T cells. These adaptive Tregs could function to reduce ongoing inflammatory responses and promote low-dose tolerance in humans, especially when Ag exposure and tolerance is transient.
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