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Schlafen 11 (SLFN11), a regulator of cell fate following DNA injury, sensitizes tumor cells to DNA-damaging agents. Patients with SLFN11-positive tumors may benefit from DNA-damaging chemotherapies. SLFN11 has been studied in different types of cancer including colorectal carcinomas. However, colorectal carcinomas with diffuse positivity (expression in ≥80% of tumor cells) have not been meticulously characterized. SLFN11 immunostaining of tumor microarrays (TMAs) with 3,300 primary CRCs identified 65 (~2.0%) tumors with focal staining (<10% of tumor nuclei positive), 83 (~2.5%) with patchy (≥10% and <80%) and 51 (~1.5%) with diffuse (≥80%) SLFN11 positivity. The latter was confirmed on full sections from donor blocks in 31 (~1%) cases, which were further studied including evaluation of additional immunohistochemical markers, genotyping with targeted DNA sequencing, and assessment of microsatellite instability. SLFN11-positive carcinomas were mostly (21/31, 68%) right-sided tumors with a female predominance (21/31, 68%) and median age of 67 years. Eighteen of 31 (58%) contained areas of mucinous differentiation. Deficiency of mismatch repair proteins was detected in 65% (20/31) of SLFN11-positive carcinomas. Moreover, MLH1 (n = 2), MSH2, MSH6, and PMS2 germline mutations were identified in 25% (5/20) of patients with mismatch repair deficient tumors. BRAF p.V600E mutation was found in 45% (9/20) of mismatch repair deficient, but only 1 of 11 proficient tumors. Colorectal carcinomas with diffuse SLFN11 positivity were often mismatch repair deficient tumors with their typical clinical, morphological, and molecular characteristics.
- MeSH
- dospělí MeSH
- jaderné proteiny * metabolismus MeSH
- karcinom * metabolismus patologie MeSH
- kolon * metabolismus patologie MeSH
- kolorektální nádory * metabolismus patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikrosatelitní nestabilita * MeSH
- nádorové biomarkery metabolismus MeSH
- oprava chybného párování bází DNA MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Dual reporters encoding two distinct proteins within the same mRNA have had a crucial role in identifying and characterizing unconventional mechanisms of eukaryotic translation. These mechanisms include initiation via internal ribosomal entry sites (IRESs), ribosomal frameshifting, stop codon readthrough and reinitiation. This design enables the expression of one reporter to be influenced by the specific mechanism under investigation, while the other reporter serves as an internal control. However, challenges arise when intervening test sequences are placed between these two reporters. Such sequences can inadvertently impact the expression or function of either reporter, independent of translation-related changes, potentially biasing the results. These effects may occur due to cryptic regulatory elements inducing or affecting transcription initiation, splicing, polyadenylation and antisense transcription as well as unpredictable effects of the translated test sequences on the stability and activity of the reporters. Unfortunately, these unintended effects may lead to misinterpretation of data and the publication of incorrect conclusions in the scientific literature. To address this issue and to assist the scientific community in accurately interpreting dual-reporter experiments, we have developed comprehensive guidelines. These guidelines cover experimental design, interpretation and the minimal requirements for reporting results. They are designed to aid researchers conducting these experiments as well as reviewers, editors and other investigators who seek to evaluate published data.
- MeSH
- Eukaryota genetika MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- proteosyntéza genetika MeSH
- reportérové geny * MeSH
- směrnice jako téma MeSH
- výzkumný projekt normy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Multisystem inflammatory syndrome in children (MIS-C) is a rare condition following SARS-CoV-2 infection associated with intestinal manifestations. Genetic predisposition, including inborn errors of the OAS-RNAseL pathway, has been reported. We sequenced 154 MIS-C patients and utilized a novel statistical framework of gene burden analysis, "burdenMC," which identified an enrichment for rare predicted-deleterious variants in BTNL8 (OR = 4.2, 95% CI: 3.5-5.3, P < 10-6). BTNL8 encodes an intestinal epithelial regulator of Vγ4+γδ T cells implicated in regulating gut homeostasis. Enrichment was exclusive to MIS-C, being absent in patients with COVID-19 or bacterial disease. Using an available functional test for BTNL8, rare variants from a larger cohort of MIS-C patients (n = 835) were tested which identified eight variants in 18 patients (2.2%) with impaired engagement of Vγ4+γδ T cells. Most of these variants were in the B30.2 domain of BTNL8 implicated in sensing epithelial cell status. These findings were associated with altered intestinal permeability, suggesting a possible link between disrupted gut homeostasis and MIS-C-associated enteropathy triggered by SARS-CoV-2.
- MeSH
- butyrofiliny * genetika metabolismus MeSH
- COVID-19 * genetika komplikace imunologie virologie MeSH
- dítě MeSH
- genetická predispozice k nemoci MeSH
- heterozygot MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- předškolní dítě MeSH
- SARS-CoV-2 * MeSH
- syndrom systémové zánětlivé reakce * genetika MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Alemtuzumab (ALEM) is a humanised monoclonal antibody that depletes circulating lymphocytes by selectively targeting CD52, which is expressed in high levels on T- and B-lymphocytes. This depletion is followed by lymphocyte repopulation and a cytokine expression shift towards a lesser inflammatory profile, both of which may contribute to prolonged efficacy. National recommendations for enrolling and treating multiple sclerosis (MS) patients with ALEM have been established. However, there are no recommendations in place for the treatment of MS reactivation after the ALEM treatment. OBJECTIVES: To evaluate the effectiveness and safety of the use of ALEM and to analyse subsequent disease-modifying treatments (DMTs). A multidimensional prediction model was developed to make a patient-specific prognosis regarding the response to ALEM. DESIGN: A multicentre, prospective, non-controlled, non-interventional, observational cohort study. METHODS: Relapsing multiple sclerosis patients (RMSp) who received ⩾1 dose of ALEM were enrolled. In each treatment year, the following baseline and prospective data were collected: age, MS history, number, type and duration of previous disease-modifying treatment (PDMT), relapse rate (REL), expanded disability status scale (EDSS), magnetic resonance imaging and serious adverse events (AE). In cases of reactivation of MS, all data about the subsequent DMT were collected. RESULTS: A total of 142 RMSp from 10 MS Slovak Centres fulfilled the inclusion criteria. The average age was 35 years (standard error 8.56). The overall average EDSS was 3.87 (1.46) when ALEM was started. The average duration of PDMT was 6.0 (4.04) years, and the median number of PDMTs was 3 (0-5), while the patients were mostly treated with 2 or 3 DMTs (>65.00%). Post-ALEM treatment was needed in 39 cases (27.46%). The most frequent post-ALEM treatment indicated was ocrelizumab, followed by natalizumab (NAT), siponimod and cladribine. The ocrelizumab and NAT treatment bring little benefit to patients. Siponimod showed less EDSS increase in contrast to ocrelizumab and NAT. Another repopulation therapy, cladribine, may also be an effective option. Statistically significant predictors for the expected EDSS are age (p-value <0.0001), number of ALEM cycles (0.0066), high number of PDMT (0.0459) and the occurrence of relapses (<0.0001). There was no statistically significant effect on the patient's gender (0.6038), duration of disease-modifying treatment before alemtuzumab (0.4466), or the occurrence of AE (0.6668). CONCLUSION: The study confirms the positive effect of ALEM on clinical and radiological outcomes. We need more data from long-term sequencing studies.
- Publikační typ
- časopisecké články MeSH
Congenital athymia is a life-limiting disorder due to rare inborn errors of immunity causing impaired thymus organogenesis or abnormal thymic stromal cell development and function. Athymic infants have a T-lymphocyte-negative, B-lymphocyte-positive, natural killer cell-positive immunophenotype with profound T-lymphocyte deficiency and are susceptible to severe infections and autoimmunity. Patients variably display syndromic features. Expanding access to newborn screening for severe combined immunodeficiency and T lymphocytopenia and broad genetic testing, including next-generation sequencing technologies, increasingly facilitate their timely identification. The recommended first-line treatment is allogeneic thymus transplantation, which is a specialized procedure available in Europe and the United States. Outcomes for athymic patients are best with early diagnosis and thymus transplantation before the development of infectious and inflammatory complications. These guidelines on behalf of the European Society for Immunodeficiencies provide a comprehensive review for clinicians who manage patients with inborn thymic stromal cell defects; they offer clinical practice recommendations focused on the diagnosis, investigation, risk stratification, and management of congenital athymia with the aim of improving patient outcomes.
- MeSH
- lidé MeSH
- management nemoci MeSH
- novorozenec MeSH
- syndromy imunologické nedostatečnosti * terapie diagnóza imunologie MeSH
- thymus imunologie MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- směrnice pro lékařskou praxi MeSH
- Geografické názvy
- Evropa MeSH
Biological age is typically estimated using biomarkers whose states have been observed to correlate with chronological age. A persistent limitation of such aging clocks is that it is difficult to establish how the biomarker states are related to the mechanisms of aging. Somatic mutations could potentially form the basis for a more fundamental aging clock since the mutations are both markers and drivers of aging and have a natural timescale. Cell lineage trees inferred from these mutations reflect the somatic evolutionary process, and thus, it has been conjectured, the aging status of the body. Such a timer has been impractical thus far, however, because detection of somatic variants in single cells presents a significant technological challenge. Here, we show that somatic mutations detected using single-cell RNA sequencing (scRNA-seq) from thousands of cells can be used to construct a cell lineage tree whose structure correlates with chronological age. De novo single-nucleotide variants (SNVs) are detected in human peripheral blood mononuclear cells using a modified protocol. A default model based on penalized multiple regression of chronological age on 31 metrics characterizing the phylogenetic tree gives a Pearson correlation of 0.81 and a median absolute error of ~4 years between predicted and chronological ages. Testing of the model on a public scRNA-seq dataset yields a Pearson correlation of 0.85. In addition, cell tree age predictions are found to be better predictors of certain clinical biomarkers than chronological age alone, for instance glucose, albumin levels, and leukocyte count. The geometry of the cell lineage tree records the structure of somatic evolution in the individual and represents a new modality of aging timer. In addition to providing a numerical estimate of "cell tree age," it unveils a temporal history of the aging process, revealing how clonal structure evolves over life span. Cell Tree Rings complements existing aging clocks and may help reduce the current uncertainty in the assessment of geroprotective trials.
- MeSH
- biologické markery MeSH
- dlouhověkost MeSH
- fylogeneze MeSH
- leukocyty mononukleární * MeSH
- lidé MeSH
- stárnutí * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
STAT1 gain-of-function (GOF) mutations underlie an inborn error of immunity hallmarked by chronic mucocutaneous candidiasis (CMC). Beyond the fungal susceptibility, attributed to Th17 failure, over half of the reported patients suffer from autoimmune manifestations, mechanism of which has not been explained yet. We hypothesized that the STAT1 mutations would affect dendritic cells' (DCs) properties and alter their inflammatory and tolerogenic functions. To test the hypothesis, we generated monocyte-derived DCs (moDCs) and tolerogenic DCs (tDCs). Functional and signaling studies, co-culture experiments and RNA sequencing demonstrated that STAT1 GOF DCs were profoundly altered in their phenotype and functions, characterized by loss of tolerogenic functions, proinflammatory skew and decreased capacity to induce Th17. Cytokine signaling, autophagy and metabolic processes were identified as the most prominently altered cellular processes. The results suggest that DCs are directly involved in STAT1 GOF-associated immune pathology, possibly contributing to both autoimmune manifestations and the failure of antifungal defense.
f-statistics have emerged as a first line of analysis for making inferences about demographic history from genome-wide data. Not only are they guaranteed to allow robust tests of the fits of proposed models of population history to data when analyzing full genome sequencing data-that is, all single nucleotide polymorphisms (SNPs) in the individuals being analyzed-but they are also guaranteed to allow robust tests of models for SNPs ascertained as polymorphic in a population that is an outgroup in a phylogenetic sense to all groups being analyzed. True "outgroup ascertainment" is in practice impossible in humans because our species has arisen from a substructured ancestral population that does not descend from a homogeneous ancestral population going back many hundreds of thousands of years into the past. However, initial studies suggested that non-outgroup-ascertainment schemes might produce robust enough results using f-statistics, and that motivated widespread fitting of models to data using non-outgroup-ascertained SNP panels such as the "Affymetrix Human Origins array" which has been genotyped on thousands of modern individuals from hundreds of populations, or the "1240k" in-solution enrichment reagent which has been the source of about 70% of published genome-wide data for ancient humans. In this study, we show that while analyses of population history using such panels work well for studies of relationships among non-African populations and one African outgroup, when co-modeling more than one sub-Saharan African and/or archaic human groups (Neanderthals and Denisovans), fitting of f-statistics to such SNP sets is expected to frequently lead to false rejection of true demographic histories, and failure to reject incorrect models. Analyzing panels of SNPs polymorphic in archaic humans, which has been suggested as a solution for the ascertainment problem, has limited statistical power and retains important biases. However, by carrying out simulations of diverse demographic histories, we show that bias in inferences based on f-statistics can be minimized by ascertaining on variants common in a union of diverse African groups; such ascertainment retains high statistical power while allowing co-analysis of archaic and modern groups.
- MeSH
- Afričané * genetika MeSH
- biologická variabilita populace genetika MeSH
- černoši genetika MeSH
- demografie * dějiny MeSH
- fylogeneze * MeSH
- genotyp MeSH
- jednonukleotidový polymorfismus * genetika MeSH
- lidé MeSH
- mapování chromozomů MeSH
- neandertálci genetika MeSH
- statistické modely MeSH
- zkreslení výsledků (epidemiologie) MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
... Organization of the human genome 145 -- 10.4 Genes and gene families 145 -- 10.5 Tandem repetitive sequences ... ... 147 -- 10.6 Dispersed repetitive sequences - mobile genetic elements 149 -- 10.7 The human mitochondrial ... ... instability and basic types of mutations 155 -- 11.2 Gene mutations 156 -- 11.3 Mutations caused by errors ...
1st edition 268 stran : ilustrace ; 30 cm
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- Učební osnovy. Vyučovací předměty. Učebnice
- NLK Obory
- biologie
- NLK Publikační typ
- učebnice vysokých škol
REM sleep without atonia (RWA) is the hallmark of isolated REM sleep behavior disorder (iRBD) and is caused by neurodegeneration of brainstem structures. Previously, quantitative susceptibility mapping (QSM) was shown to detect microstructural tissue changes in neurodegenerative diseases. The goal of the study was to compare brainstem magnetic susceptibility (MS) in iRBD and controls using the voxel-based QSM approach and to examine the association between brainstem MS and severity of RWA in iRBD. Sixty iRBD patients and 41 healthy controls were included in the study. Phasic, tonic, mixed RWA and SINBAR score was quantified. QSM maps were reconstructed with QSMbox software from a multi-gradient-echo sequence acquired at 3T MRI system and normalized using a custom T1 template. Voxel-based analysis with age and gender as covariates was performed using a two-sample t-test model for between-group comparison and using a linear regression model for association with the RWA parameters. Statistical maps were generated using threshold free cluster enhancement with p-value p < 0.05, corrected for family wise error. Compared to controls, the iRBD group had higher MS in bilateral substantia nigra (SN), red nucleus and the ventral tegmental area. MS positively correlated with iRBD duration in the right pedunculotegmental nucleus and white matter of caudal mesencephalic and pontine tegmentum and with phasic RWA in bilateral SN. QSM was able to detect MS abnormalities in several brainstem structures in iRBD. Association of MS levels in the brainstem with the intensity of RWA suggests that increased iron content in SN is related to RWA severity.
- Publikační typ
- časopisecké články MeSH