invasive pathogen
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Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with patients having unresectable or metastatic disease at diagnosis, with poor prognosis and very short survival. Given that genetic variation within autophagy-related genes influences autophagic flux and susceptibility to solid cancers, we decided to investigate whether 55,583 single nucleotide polymorphisms (SNPs) within 234 autophagy-related genes could influence the risk of developing PDAC in three large independent cohorts of European ancestry including 12,754 PDAC cases and 324,926 controls. The meta-analysis of these populations identified, for the first time, the association of the BIDrs9604789 variant with an increased risk of developing the disease (ORMeta = 1.31, p = 9.67 × 10-6). We also confirmed the association of TP63rs1515496 and TP63rs35389543 variants with PDAC risk (OR = 0.89, p = 6.27 × 10-8 and OR = 1.16, p = 2.74 × 10-5). Although it is known that BID induces autophagy and TP63 promotes cell growth, cell motility and invasion, we also found that carriers of the TP63rs1515496G allele had increased numbers of FOXP3+ Helios+ T regulatory cells and CD45RA+ T regulatory cells (p = 7.67 × 10-4 and p = 1.56 × 10-3), but also decreased levels of CD4+ T regulatory cells (p = 7.86 × 10-4). These results were in agreement with research suggesting that the TP63rs1515496 variant alters binding sites for FOXA1 and CTCF, which are transcription factors involved in modulating specific subsets of regulatory T cells. In conclusion, this study identifies BID as new susceptibility locus for PDAC and confirms previous studies suggesting that the TP63 gene is involved in the development of PDAC. This study also suggests new pathogenic mechanisms of the TP63 locus in PDAC.
- MeSH
- autofagie * genetika MeSH
- běloši genetika MeSH
- duktální karcinom slinivky břišní * genetika patologie MeSH
- forkhead transkripční faktory MeSH
- genetická predispozice k nemoci * MeSH
- hepatocytární jaderný faktor 3-alfa genetika metabolismus MeSH
- jednonukleotidový polymorfismus * MeSH
- kohortové studie MeSH
- lidé MeSH
- nádorové biomarkery * genetika MeSH
- nádorové supresorové proteiny * genetika MeSH
- nádory slinivky břišní * genetika patologie MeSH
- studie případů a kontrol MeSH
- transkripční faktory genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
Super- and low-shedding phenomena have been observed in genetically homogeneous hosts infected by a single bacterial strain. To decipher the mechanisms underlying these phenotypes, we conducted an experiment with chicks infected with Salmonella Enteritidis in a non-sterile isolator, which prevents bacterial transmission between animals while allowing the development of the gut microbiota. We investigated the impact of four commensal bacteria called Mix4, inoculated at hatching, on chicken systemic immune response and intestinal microbiota composition and functions, before and after Salmonella infection. Our results revealed that these phenotypes were not linked to changes in cell invasion capacity of bacteria during infection. Mix4 inoculation had both short- and long-term effects on immune response and microbiota and promoted the low-shedder phenotype. Kinetic analysis revealed that Mix4 activated immune response from day 4, which modified the microbiota on day 6. This change promotes a more fermentative microbiota, using the aromatic compounds degradation pathway, which inhibited Salmonella colonization by day 11 and beyond. In contrast, control animals exhibited a delayed TNF-driven pro-inflammatory response and developed a microbiota using anaerobic respiration, which facilitates Salmonella colonization and growth. This strategy offers promising opportunities to strengthen the barrier effect against Salmonella and possibly other pathogens.
- MeSH
- Bacteria * klasifikace genetika izolace a purifikace MeSH
- kur domácí * mikrobiologie imunologie MeSH
- nemoci drůbeže * mikrobiologie imunologie prevence a kontrola MeSH
- Salmonella enteritidis * imunologie růst a vývoj MeSH
- salmonelová infekce u zvířat * mikrobiologie imunologie prevence a kontrola MeSH
- střevní mikroflóra * MeSH
- symbióza MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVE: patients with type 2 diabetes (T2DM) and obesity are generally known to have increased risk of various types of cancer, though studies addressing associations between T2DM/obesity and thyroid cancer are inconclusive. The aim of our study was to evaluate the risk of thyroid cancer focusing on diabetic patients under conditions of euthyroid status. A retrospective study in 184 patients was performed. Three cohorts were established according to tumor histology: malignant (M), benign (B) and low-risk carcinoma (MB). Fisher's exact test and Kruskal-Wallis one-way ANOVA of ranks were used for statistical analysis. The M (39.1 %), B (57.6 %) and MB (3.3 %) cohorts had comparable age (p=0.4), BMI (p=0.452), glycaemia (p=0.834), Hb1AC (p=0.157) and HOMA-IR (p=0.235). T2DM patients had larger thyroid gland volumes (28.8 vs 17.6 mL;p=0.001) compared to the cohort with normal glucose tolerance. Compared to women, men had more frequently present distal metastases (p=0.017), minimally invasive disease (p=0.027), more advanced staging (p=0.01) and positive pathogenic mutations in the TERT gene (p=0.009);these results were also significant for the diabetic male cohort (p=0.026). Type 2 diabetes and obesity are not risk factors for thyroid cancer, but a subgroup of males seems to have thyroid cancers of poorer prognosis. In general, diabetic patients with insulin resistance and hyperinsulinemia are also prone to have a goiter. KEY WORDS: Thyroid cancer, Type 2 diabetes, Obesity, Thyroid nodule, Insulin resistance.
- MeSH
- diabetes mellitus 2. typu * epidemiologie komplikace MeSH
- dospělí MeSH
- kohortové studie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory štítné žlázy * epidemiologie patologie MeSH
- obezita * komplikace epidemiologie MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
The ApxIVA protein belongs to a distinct class of a "clip and link" activity of Repeat-in-ToXin (RTX) exoproteins. Along with the three other pore-forming RTX toxins (ApxI, ApxII and ApxIII), ApxIVA serves as a major virulence factor of Actinobacillus pleuropneumoniae, the causative agent of porcine pneumonia. The gene encoding ApxIVA is located on a bicistronic operon downstream of the orf1 gene and is expressed exclusively under in vivo conditions. Both ApxIVA and ORF1 are essential for full virulence of A. pleuropneumoniae, but the molecular mechanisms by which they contribute to the pathogenicity are not yet understood. Here, we provide a comprehensive structural and functional analysis of ApxIVA and ORF1 proteins. Our findings reveal that the N-terminal segment of ApxIVA shares structural similarity with colicin M (ColM)-like bacteriocins and exhibits an antimicrobial activity. The ORF1 protein resembles the colicin M immunity protein (Cmi) and, like Cmi, is exported to the periplasm through its N-terminal signal peptide. Additionally, ORF1 can protect bacterial cells from the antimicrobial activity of ApxIVA, suggesting that ORF1 and ApxIVA function as an antibacterial toxin-immunity pair. Moreover, we demonstrate that fetal bovine serum could elicit ApxIVA and ORF1 production under in vitro conditions. These findings highlight the coordinated action of various RTX determinants, where the fine-tuned spatiotemporal production of ApxIVA may enhance the fitness of A. pleuropneumoniae, facilitating its invasion to a resident microbial community on the surface of airway mucosa.
- MeSH
- Actinobacillus pleuropneumoniae * genetika imunologie MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální proteiny * genetika metabolismus imunologie MeSH
- bakteriální toxiny genetika metabolismus imunologie MeSH
- faktory virulence genetika MeSH
- infekce bakteriemi rodu Actinobacillus mikrobiologie veterinární MeSH
- koliciny genetika metabolismus MeSH
- operon * MeSH
- prasata MeSH
- regulace genové exprese u bakterií MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Adult and paediatric patients with pathogenic variants in the gene encoding succinate dehydrogenase (SDH) subunit B (SDHB) often have locally aggressive, recurrent or metastatic phaeochromocytomas and paragangliomas (PPGLs). Furthermore, SDHB PPGLs have the highest rates of disease-specific morbidity and mortality compared with other hereditary PPGLs. PPGLs with SDHB pathogenic variants are often less differentiated and do not produce substantial amounts of catecholamines (in some patients, they produce only dopamine) compared with other hereditary subtypes, which enables these tumours to grow subclinically for a long time. In addition, SDHB pathogenic variants support tumour growth through high levels of the oncometabolite succinate and other mechanisms related to cancer initiation and progression. As a result, pseudohypoxia and upregulation of genes related to the hypoxia signalling pathway occur, promoting the growth, migration, invasiveness and metastasis of cancer cells. These factors, along with a high rate of metastasis, support early surgical intervention and total resection of PPGLs, regardless of the tumour size. The treatment of metastases is challenging and relies on either local or systemic therapies, or sometimes both. This Consensus statement should help guide clinicians in the diagnosis and management of patients with SDHB PPGLs.
- MeSH
- dítě MeSH
- dospělí MeSH
- feochromocytom * genetika terapie diagnóza MeSH
- lidé MeSH
- nádory nadledvin * genetika terapie diagnóza MeSH
- paragangliom * genetika terapie MeSH
- sukcinátdehydrogenasa genetika MeSH
- zárodečné mutace genetika MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
nfekce způsobené bakterií Streptococcus pneumoniae představují stále závažný zdravotnický problém. Projevují se širokou škálou příznaků, od méně závažných neinvazivních, které jsou lokalizovány na sliznicích, po tzv. invazivní onemocnění. V důsledku stárnutí populace, a tudíž i rostoucího počtu rizikových pacientů, narůstá riziko častějšího výskytu invazivních forem pneumokokových infekcí, s dopady na zdraví jednotlivců a na zdravotnický systém. Ačkoli léčba antibiotiky je dostupná, v posledních letech narůstá riziko vzniku nežádoucí antibiotické rezistence. Význam včasné prevence je tak zcela na místě. Současné pneumokokové vakcíny jsou schopny ovlivňovat výskyt jak invazivních, tak i některých neinvazivních onemocnění. Rozeznáváme přes sto sérotypů bakterie Streptococcus pneumoniae, které jsou pro člověka patogenní. Řada z nich je dnes již pokryta v konjugovaných nebo polysacharidových vakcínách.
Pneumococcal infections remain a serious problem in many countries around the world. They manifest themselves in a wide range of symptoms, from less serious non-invasive ones localized on the mucous membranes, to so-called invasive diseases. As a result of the aging of the population, and therefore the growing number of patients at risk, the risk of more frequent occurrence of invasive forms of pneumococcal infections is increasing, with impacts on the health of individuals and the healthcare system. Although antibiotic treatment is available, the risk of unwanted antibiotic resistance has been increasing in recent years. Early prevention is very important. Current pneumococcal vaccines are able to influence the occurrence of both invasive and some non-invasive diseases. We recognize over one hundred serotypes of the Streptococcus pneumoniae, pathogenic for humans. A number of them are already covered today in conjugated or polysaccharide vaccines.
Background: Recent studies have suggested that pathogenic variants of the DICER1 gene could be a driver of alterations in some pediatric thyroid nodules, but data are still limited. The aim of this study was to detect variants in the DICER1 gene in a large cohort of pediatric thyroid nodules and then correlate them with clinicopathological data, with a focus on the disease prognosis in patients with thyroid carcinoma. Methods: This retrospective cohort study consisted of 350 pediatric and young adult patients (aged 2-21 years) with thyroid nodules, from whom 275 fresh-frozen thyroid nodule samples and 92 fine-needle aspiration biopsy (FNAB) samples were collected. After an analysis of variants in major genetic alterations of thyroid tumors, variants in the DICER1 gene were identified using next-generation sequencing and multiplex ligation-dependent probe amplification methods. Peripheral blood was analyzed from patients with DICER1-positive tumors. The results of genetic analysis were then correlated with clinicopathological data. Results: Variants in the DICER1 gene were detected in a total of 24/350 (6.9%; 95%CI [4.4;10.0]) pediatric and young adult patients, respectively, in 10/119 (8.4%; [4.1;14.9]) patients with benign fresh-frozen tissue, in 8/141 (5.7%; [1.9;9.5]) with papillary thyroid carcinoma (PTC) and in 6/86 (7.0%; [4.1;14.6]) patients with FNAB. No other gene alteration was found in DICER1-positive samples. Germline DICER1 variants were identified in 11/24 (45.8%; [25.6;67.2]) patients. Two somatic (biallelic) variants in the DICER1 gene were found in 9/24 (37.5%; [18.8;59.4]) thyroid nodules. Somatic deletions of at least 3 Mbp long were revealed in 2/24 (8.3%; [1.0;27.0]) cases. DICER1-positive PTCs were significantly associated with the follicular subtype of PTC (p = 0.001), encapsulation (p = 0.006) and were larger in size (p = 0.035), but with no extrathyroidal extension (p = 0.039), and less frequent lymph node metastases (p = 0.003) compared with DICER1-negative PTCs. Patients with DICER1-positive PTC had an excellent response to treatment in 75% of cases. Conclusions: Variants of the DICER1 gene are frequently found in the thyroid nodules of pediatric and young adult patients. In our patients, DICER1-positive PTCs showed low invasiveness. Our findings support considering more conservative management for DICER1-positive low-risk PTCs.
- MeSH
- DEAD-box RNA-helikasy * genetika MeSH
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- nádory štítné žlázy * genetika patologie MeSH
- papilární karcinom štítné žlázy genetika patologie MeSH
- předškolní dítě MeSH
- prognóza MeSH
- retrospektivní studie MeSH
- ribonukleasa III * genetika MeSH
- tenkojehlová biopsie MeSH
- uzly štítné žlázy * genetika patologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Background/Objectives: PET imaging of bacterial infection could potentially provide added benefits for patient care through non-invasive means. [68Ga]Ga-desferrioxamine B-a radiolabelled siderophore-shows specific uptake by human-pathogenic bacteria like Staphylococcus aureus or Pseudomonas aeruginosa and sufficient serum stability for clinical application. In this report, we present data for automated production of [68Ga]Ga-desferrioxamine B on two different cassette-based synthesis modules (Modular-Lab PharmTracer and GRP 3V) utilising commercially obtainable cassettes together with a licensed 68Ge/68Ga radionuclide generator. Methods: Quality control, including the determination of radiochemical purity, as well as a system suitability test, was set up via RP-HPLC on a C18 column. The two described production processes use an acetic acid/acetate buffer system with ascorbic acid as a radical scavenger for radiolabelling, yielding ready-to-use formulations with sufficient activity yield. Results: Batch data analysis demonstrated radiochemical purity of >95% by RP-HPLC combined with ITLC and excellent stability up to 2 h after synthesis. Specifications for routine production were set up and validated with four masterbatches for each synthesis module. Conclusions: Based on this study, an academic clinical trial for imaging of bacterial infection was initiated. Both described synthesis methods enable automated production of [68Ga]Ga-desferrioxamine B in-house with high reproducibility for clinical application.
- Publikační typ
- časopisecké články MeSH
Radiolabelled puromycin analogues will allow the quantification of protein synthesis through nuclear medicine-based imaging. A particularly useful application could be the non-invasive longitudinal visualisation of mycobacterial activity through direct quantification of puromycin binding. This study assesses the value of [68Ga]Ga-DOTA-puromycin in the visualisation of mycobacteria through positron emission tomography combined with magnetic resonance imaging (μPET/MRI). The radiopharmaceutical was produced by previously published and validated methods. [68Ga]Ga-DOTA-Puromycin imaging was performed on severe immunodeficient mice infected with Bacille Calmette-Guérin-derived M. Bovis (BCG). Acute and chronic infection stages were examined by μPET/MRI. A follow-up group of animals acted as controls (animals bearing S. aureus-derived infection and sterile inflammation) to assess tracer selectivity. [68Ga]Ga-DOTA-puromycin-μPET/MRI images revealed the acute, widespread infection within the right upper shoulder and armpit. Also, [68Ga]Ga-DOTA-puromycin signal sensitivity measured after a 12-week period was lower than that of [18F]FDG-PET in the same animals. A suitable correlation between normalised uptake values (NUV) and gold standard histopathological analysis confirms accurate tracer accumulation in viable bacteria. The radiopharmaceutical showed infection selectivity over inflammation but accumulated in both M. Bovis and S. Aureus, lacking pathogen specificity. Overall, [68Ga]Ga-DOTA-puromycin exhibits potential as a tool for non-invasive protein synthesis visualization, albeit without pathogen selectivity.
- MeSH
- heterocyklické sloučeniny monocyklické chemie MeSH
- magnetická rezonanční tomografie * metody MeSH
- Mycobacterium bovis * MeSH
- mykobakteriózy diagnostické zobrazování mikrobiologie MeSH
- myši SCID MeSH
- myši MeSH
- organokovové sloučeniny MeSH
- pozitronová emisní tomografie * metody MeSH
- radiofarmaka * chemie MeSH
- radioizotopy galia * MeSH
- tuberkulóza diagnostické zobrazování mikrobiologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Invasive fungal disease (IFD) presents a life-threatening condition in immunocompromised patients, thus often prompting empirical administration of antifungal treatment, without adequate mycological evidence. Over the past years, wide use of antifungal prophylaxis resulted in decreased occurrence of IFD but has contributed to changes in the spectrum of fungal pathogens, revealing the occurrence of previously rare fungal genera causing breakthrough infections. The expanding spectrum of clinically relevant fungal pathogens required the implementation of screening approaches permitting broad rather than targeted fungus detection to support timely onset of pre-emptive antifungal treatment. To address this diagnostically important aspect in a prospective setting, we analyzed 935 serial peripheral blood (PB) samples from 195 pediatric and adult patients at high risk for IFD, involving individuals displaying febrile neutropenia during treatment of hematological malignancies or following allogeneic hematopoietic stem cell transplantation. Two different panfungal-PCR-screening methods combined with ensuing fungal genus identification by Sanger sequencing were employed. In the great majority of PB-specimens displaying fungal DNAemia, the findings were transient and revealed fungi commonly regarded as non-pathogenic or rarely pathogenic even in the highly immunocompromised patient setting. Hence, to adequately exploit the diagnostic potential of panfungal-PCR approaches for detecting IFD, particularly if caused by hitherto rarely observed fungal pathogens, it is necessary to confirm the findings by repeated testing and to identify the fungal genus present by ensuing analysis. If applied appropriately, panfungal-PCR-screening can help prevent unnecessary empirical therapy, and conversely, contribute to timely employment of effective pre-emptive antifungal treatment strategies.
- MeSH
- antifungální látky terapeutické užití MeSH
- dítě MeSH
- DNA fungální * analýza MeSH
- dospělí MeSH
- febrilní neutropenie * mikrobiologie MeSH
- hematologické nádory komplikace MeSH
- houby izolace a purifikace genetika MeSH
- imunokompromitovaný pacient * MeSH
- invazivní mykotické infekce epidemiologie prevence a kontrola etiologie mikrobiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- předškolní dítě MeSH
- prevalence MeSH
- prospektivní studie MeSH
- senioři MeSH
- transplantace hematopoetických kmenových buněk škodlivé účinky MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- dopisy MeSH