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Craig Wooten posted an update 1 week, 3 days ago
However, more studies regarding these DEGs and type I IFN signaling in this infectious context are necessary to more fully clarify the underlying mechanisms that arise in response to PPE57 during MTB infection.Enterotoxigenic Escherichia coli (ETEC) is a WHO priority pathogen and vaccine target which causes infections in low-income and middle-income countries, travelers visiting endemic regions. The global urgent demand for an effective preventive intervention has become more pressing as ETEC strains have become increasingly multiple antibiotic resistant. However, the vaccine development pipeline has been slow to address this urgent need. To date, vaccine development has focused mainly on canonical antigens such as colonization factors and expressed toxins but due to genomic plasticity of this enteric pathogen, it has proven difficult to develop effective vaccines. In this study, we investigated the highly conserved non-canonical vaccine candidate YghJ/SsLE. Using the mass spectrometry-based method BEMAP, we demonstrate that YghJ is hyperglycosylated in ETEC and identify 54 O-linked Set/Thr residues within the 1519 amino acid primary sequence. The glycosylation sites are evenly distributed throughout the sequence and do not appear to affect the folding of the overall protein structure. Although the glycosylation sites only constitute a minor subpopulation of the available epitopes, we observed a notable difference in the immunogenicity of the glycosylated YghJ and the non-glycosylated protein variant. We can demonstrate by ELISA that serum from patients enrolled in an ETEC H10407 controlled infection study are significantly more reactive with glycosylated YghJ compared to the non-glycosylated variant. This study provides an important link between O-linked glycosylation and the relative immunogenicity of bacterial proteins and further highlights the importance of this observation in considering ETEC proteins for inclusion in future broad coverage subunit vaccine candidates.
Diagnosis of
(MTB) infection can be confirmed by Xpert assays within hours. However, when sample size does not allow performing both culture and Xpert, or if Xpert is negative, then formal diagnosis of MTB relies on culture and time to detection of growth (TDG) becomes critical for clinical management.
To determine TDG in Xpert negative samples, or in samples in which Xpert could not be performed, in a low-incidence area for MTB.
Retrospective analysis (2015-2020) of a database including all cultures for mycobacteria in a University Hospital covering approximately 500’000 inhabitants. Analysis was restricted to culture positive (C+) samples for MTB for which 1/Xpert was negative or could not be performed because of limited sample volume, and 2/collected from subjects treated less than 24 hours. TDG was analyzed according to microscopy, origin of sample (pulmonary or not) and presence of cavitation.
Among 837 C+ samples for MTB, 236 samples (80% of respiratory origin) from 147 patients fulfilled study criteria; 78 samples (49 patients, 33%) were acid-fast bacilli (AFB) positive. Median (IQR) TDG was 25 (17; 40) days for all samples. TDG exceeded 28 days in 43% of samples and was significantly shorter in AFB+
AFB- samples, and samples from cavitary
non cavitary or extra-thoracic disease.
In Xpert negative samples, or samples for which Xpert could not be performed, TDG exceeded 4 weeks in 43% of samples. AFB+ and samples from cavitary lung disease had a significantly shorter TDG.
In Xpert negative samples, or samples for which Xpert could not be performed, TDG exceeded 4 weeks in 43% of samples. AFB+ and samples from cavitary lung disease had a significantly shorter TDG.Clinical manifestations of leishmaniasis range from self-healing, cutaneous lesions to fatal infections of the viscera. With no preventative Leishmania vaccine available, the frontline option against leishmaniasis is chemotherapy. Unfortunately, currently available anti-Leishmania drugs face several obstacles, including toxicity that limits dosing and emergent drug resistant strains in endemic regions. It is, therefore, imperative that more effective drug formulations with decreased toxicity profiles are developed. Previous studies had shown that 2-(((5-Methyl-2-thienyl)methylene)amino)-N-phenylbenzamide (also called Retro-2) has efficacy against Leishmania infections. Structure-activity relationship (SAR) analogs of Retro-2, using the dihydroquinazolinone (DHQZ) base structure, were subsequently described that are more efficacious than Retro-2. However, considering the hydrophobic nature of these compounds that limits their solubility and uptake, the current studies were initiated to determine whether the solubility of Retro-2 and its SAR analogs could be enhanced through encapsulation in amphiphilic polymer nanoparticles. learn more We evaluated encapsulation of these compounds in the amphiphilic, thermoresponsive oligo(ethylene glycol) methacrylate-co-pentafluorostyrene (PFG30) copolymer that forms nanoparticle aggregates upon heating past temperatures of 30°C. The hydrophobic tracer, coumarin 6, was used to evaluate uptake of a hydrophobic molecule into PFG30 aggregates. Mass spectrometry analysis showed considerably greater delivery of encapsulated DHQZ analogs into infected cells and more rapid shrinkage of L. amazonensis communal vacuoles. Moreover, encapsulation in PFG30 augmented the efficacy of Retro-2 and its SAR analogs to clear both L. amazonensis and L. donovani infections. These studies demonstrate that encapsulation of compounds in PFG30 is a viable approach to dramatically increase bioavailability and efficacy of anti-Leishmania compounds.Coxsackievirus A6 (CVA6) is a key pathogen causing hand, foot and mouth disease (HFMD). However, there are currently no specific antiviral drugs or vaccines for treating infections caused by CVA6. In this study, human rhabdomyosarcoma (RD), African green monkey kidney (Vero), and human embryonic lung diploid fibroblast (KMB17) cells were used to isolate CVA6 from 327 anal swab and fecal samples obtained during HFMD monitoring between 2009 and 2017. The VP1 genes of the isolates were sequenced and genotyped, and the biological characteristics of the representative CVA6 strains were analyzed. A total of 37 CVA6 strains of the D3 gene subtypes were isolated from RD cells, all of which belonged to the epidemic strains in mainland China. Using the adaptive culture method, 10 KMB17 cell-adapted strains were obtained; however, no Vero cell-adapted strains were acquired. Among the KMB17 cell-adapted strains, only KYN-A1205 caused disease or partial death in suckling mice, and its virulence was stronger than its RD cell-adapted strain. The pathogenic KYN-A1205 strain caused strong tropism to the muscle tissue and led to pathological changes, including muscle necrosis and nuclear fragmentation in the forelimb and hindlimb. Sequence analysis demonstrated that the KYN-A1205 strain exhibited multiple amino acid mutations after KMB17 cell adaptation. Moreover, it showed strong pathogenicity, good immunogenicity and genetic stability, and could be used as an experimental CVA6 vaccine candidate.Understanding the etiology of cerebrospinal fluid (CSF) shunt infections and reinfections requires detailed characterization of associated microorganisms. Traditionally, identification of bacteria present in the CSF has relied on culture methods, but recent studies have used high throughput sequencing of 16S rRNA genes. Here we evaluated the method of shotgun DNA sequencing for its potential to provide additional genomic information. CSF samples were collected from 3 patients near the beginning and end of each of 2 infection episodes. Extracted total DNA was sequenced by (1) whole genome amplification followed by shotgun sequencing (WGA) and (2) high-throughput sequencing of the 16S rRNA V4 region (16S). Taxonomic assignments of sequences from WGA and 16S were compared with one another and with conventional microbiological cultures. While classification of bacteria was consistent among the 3 approaches, WGA provided additional insights into sample microbiological composition, such as showing relative abundances of microbial versus human DNA, identifying samples of questionable quality, and detecting significant viral load in some samples. One sample yielded sufficient non-human reads to allow assembly of a high-quality Staphylococcus epidermidis genome, denoted CLIMB1, which we characterized in terms of its MLST profile, gene complement (including putative antimicrobial resistance genes), and similarity to other annotated S. epidermidis genomes. Our results demonstrate that WGA directly applied to CSF is a valuable tool for the identification and genomic characterization of dominant microorganisms in CSF shunt infections, which can facilitate molecular approaches for the development of better diagnostic and treatment methods.Postpartum depression (PPD) is a mental disorder that affects pregnant women around the world, with serious consequences for mothers, families, and children. Its pathogenesis remains unclear, and medications for treating PPD that can be used during lactation remain to be identified. 919 syrup (919 TJ) is a Chinese herbal medicine that has been shown to be beneficial in the treatment of postpartum depression in both clinical and experimental studies. The mechanism of action of 919 TJ is unclear. 919 syrup is ingested orally, making the potential interaction between the drug and the gut microbiome impossible to ignore. We therefore hypothesized that 919 syrup could improve the symptoms of postpartum depression by affecting the structure and function of the intestinal flora, thereby altering hippocampal metabolism. We compared changes in hippocampal metabolism, fecal metabolism, and intestinal microflora of control BALB/c mice, mice with induced untreated PPD, and mice with induced PPD treated with 919 TJ, and found that 4-aminobutyric acid (GABA) in the hippocampus corresponded with PPD behaviors. Based on changes in GABA levels, multiple key gut bacterial species (Mucispirillum schaedleri, Bifidobacterium pseudolongum, Desulfovibrio piger, Alloprevotella tannerae, Bacteroides sp.2.1.33B and Prevotella sp. CAG755) were associated with PPD. Metabolic markers that may represent the function of the intestinal microbiota in mice with PPD were identified (Met-Arg, urocanic acid, thioetheramide-PC, L-pipecolic acid, and linoleoyl ethanolamide). The relationship between these factors is not a simple one-to-one correspondence, but more likely a network of staggered functions. We therefore believe that the composition and function of the entire intestinal flora should be emphasized in research studying the gut and PPD, rather than changes in the abundance of individual bacterial species. The introduction of this concept of “GutBalance” may help clarify the relationship between gut bacteria and systemic disease.Oral microbiota is constantly changing with the host state, whereas the oral microbiome of chronic erythematous candidiasis remains poorly understood. The aim of this study was to compare oral microbial signatures and functional profiling between chronic erythematous candidiasis and healthy subjects. Using shotgun metagenomic sequencing, we analyzed the microbiome in 12 chronic erythematous candidiasis, 12 healthy subjects, and 2 chronic erythematous candidiasis cured by antifungal therapy. We found that the salivary microbiota of chronic erythematous candidiasis was significantly different from that of healthy subjects. Among them, Rothia mucilaginosa and Streptococcus mitis were the most abundant disease-enriched species (Mann-Whitney U-test, P less then 0.05). In addition, co-occurrence network analysis showed that C. albicans formed densely connected modules with oral bacterial species and was mainly positive connected to Streptococcus species. Furthermore, we investigated the functional potentials of the microbiome and identified a set of microbial marker genes associated with chronic erythematous candidiasis.