Screening for Rare Mitochondrial Genome Variants Reveals a Potentially Novel Association between MT-CO1 and MT-TL2 Genes and Diabetes Phenotype.

Variations in several nuclear genes predisposing humans to the development of MODY diabetes have been very well characterized by modern genetic diagnostics. However, recent reports indicate that variants in the mtDNA genome may also be associated with the diabetic phenotype. As relatively little research has addressed the entire mitochondrial genome in this regard, the aim of the present study is to evaluate the genetic variations present in mtDNA among individuals susceptible to MODY diabetes. In total, 193 patients with a MODY phenotype were tested with a custom panel with mtDNA enrichment. Heteroplasmic variants were selected for further analysis via further sequencing based on long-range PCR to evaluate the potential contribution of frequent NUMTs (acronym for nuclear mitochondrial DNA) insertions. Twelve extremely rare variants with a potential damaging character were selected, three of which were likely to be the result of NUMTs from the nuclear genome. The variant m.3243A>G in MT-TL1 was responsible for 3.5% of MODY cases in our study group. In addition, a novel, rare, and possibly pathogenic leucine variant m.12278T>C was found in MT-TL2. Our findings also found the MT-CO1 gene to be over-represented in the study group, with a clear phenotype-genotype correlation observed in one family. Our data suggest that heteroplasmic variants in MT-COI and MT-TL2 genes may play a role in the pathophysiology of glucose metabolism in humans.

Suggested mechanism of CCR5Δ32, CCR2-64I and SDF 1-3'A allele frequency change in Polish and Lithuanian gene pools from the perspective of passing time.

The study aimed to determine the frequency of the alleles associated with hereditary immune response in 16 historical populations and assess which evolutionary forces may have contributed to the observed frequency fluctuation. The analysed polymorphic sites are located in three genes - CCR5, CCR2 and SDF 1 (CXCL12). Protein products are involved in the innate immune response and are also involved in various types of infections, autoimmune diseases and tumours. The frequency of the alleles found in the DNA of the studied individuals was determined by the Sanger methodology and was compared with the data obtained for modern populations. To confirm the authenticity of the obtained results, mtDNA HVRI haplotypes of all the studied samples were obtained and compared with the genetic database of the laboratory personnel who came into contact with the studied material. Based on the variability of allele frequency, advanced biostatistical analysis was used to distinguish the effect of natural selection from genetic drift, i.e. the forces operating on the polymorphic sites studied. All procedures were performed according to the guidelines for working with ancient DNA to avoid contamination with modern DNA molecules. 681 samples from 39 archaeological sites in Poland and Lithuania dated to the 40th century BC and the 19th century were studied. The biostatistical analysis showed that the fluctuations in the frequency of CCR5Δ32 in the analysed time interval could be mainly the effect of genetic drift. Nevertheless, for CCR2-64I and SDF 1-3'A, the results confirm the suggestion of negative selection as the mechanism involved. Since all the polymorphic sites encode the elements of innate immune response that are indirectly associated with the process of an HPV infection and the development of cervical cancer, the human papillomavirus may be a good candidate for a selection coefficient affecting the frequency of CCR2-64I and SDF 1-3'A. However, for CCR5Δ32, selection was not detected despite its proven role in the molecular mechanism involved in the response to an HPV infection. The presented work seems to be the first in which the problem of the pattern of CCR5Δ32, CCR2-64I and SDF 1-3'A frequency fluctuations in a temporal perspective was discussed, proposing HPV as a factor influencing the occurrence of the CCR2 and SDF1 alleles.

Gut microbiota in alopecia areata.

Introduction: In the past few years, the advancement of 16S rRNA metagenomic analysis sequencing has enabled assessing the impact of gut microbiota on the development of skin disease. Alopecia areata (AA) is a nonscarring hair loss disorder with an unknown etiopathogenesis, however, it is hypothesised that a combination of genetic and environmental factors might be involved. Although numerous studies have shown that the microbiome plays a key role at the beginning of skin diseases, the link between AA and gut dysbiosis remains unclear. Aim: To analyse the intestinal microbiome in patients suffering from AA. Material and methods: The study describes the conceivable involvement of gut microbiota in the unclear pathogenesis of AA. We enrolled 25 patients, over 18 years of age with an active state of AA who donated their stool samples. The samples were examined at the human gut microbial community at the species level by metataxonomic analysis of the full-length 16S V3-V4 sequencing. Results: The four major genera that constitute the microbiome's core are Lachnoclostridium, Bifidobacterium, Streptococcus, and Eubacterium, as well as three major phyla: Firmicutes, Proteobacteria, and Actinobacteria. Firmicutes and Proteobacteria are overrepresented in the microflora, which might suggest a disturbed microflora. Furthermore, the composition of bacterial communities suggests a loss of overall richness and a decrease in taxonomic diversity across all samples. Conclusions: This study describes, for the first time, the characteristics of the gut microbiome in AA patients and may provide new insight into the gut microbiome that may play a role in the development of AA.

Glucocorticoids Induce Partial Remission of Focal Segmental Glomerulosclerosis but Not Interstitial Nephritis in COVID-19 Acute Kidney Injury in an APOL1 Low-Risk Genotype White Patient.

BACKGROUND COVID-19 can be complicated by kidney disease, including focal segmental glomerulosclerosis (FSGS), interstitial nephritis, and acute kidney injury (AKI). Almost all known cases of COVID-19-associated glomerulonephritis have been in patients of African descent, with G1 or G2 apolipoprotein L1 (APOL1) risk alleles, and they presented collapsing type of FSGS. CASE REPORT We report a case of biopsy-confirmed non-collapsing FSGS with secondary acute interstitial nephritis and AKI in a young White man with APOL1 low-risk genotype, who had COVID-19 pneumonia. His past history included arterial hypertension, anabolic steroids, and high-protein diet. He fully recovered from type 1 respiratory failure and AKI after transfusion of COVID-19 convalescent plasma and intravenous treatment with dexamethasone administered for 16 days in a dose reduced from 16 to 2 mg/day. Due to progressing severe nephrotic proteinuria (22.6 g/24 h), intravenous methylprednisolone was administered (1500 mg divided in 3 pulses over 3 days) immediately followed by oral prednisone (0.6 mg/kg body weight), with dose reduced 19 weeks later and switched to cyclosporine A (4 mg/kg body weight). Kidney re-biopsy, at that time, showed a decrease in proportion of glomeruli affected with podocytopathy, but progression of interstitial lesions. After 23 weeks of therapy, partial remission of FSGS was attained and proteinuria dropped to 3.6 g/24 h. After 43 weeks, proteinuria decreased to 0.4 g/24 h and the serum creatinine concentration remained steady. CONCLUSIONS High-dose glucocorticoid therapy was effective in the initial treatment of COVID-19-related non-collapsing FSGS, but had no effect on interstitial changes. Introduction of cyclosporine A to the therapy contributed to remission of disease.

Screening for extremely rare pathogenic variants of monogenic diabetes using targeted panel sequencing.

AIMS: Maturity-onset diabetes of the young (MODY) is one of the rare monogenic forms of diabetes. To date, about 12 genes in the scientific literature are closely related to the occurrence of the disease phenotype. However, there is still a high prevalence of undiagnosed cases of so-called MODY-X whose genetic background is still unknown. METHODS: We performed tNGS for 523 patients with suspected MODY. Next 357 selected patients, in whom no damaging variants were found in 12 major genes causing MODY, were screened for the presence of pathogenic variants in four candidate genes (MNX1, RFX6, NKX2.2, and NKX6.1). All data were generated in one tNGS sequencing reaction and confirmed by Sanger sequencing. RESULTS: In total, we selected five potentially damaging variants, in eight patients, in RFX6, NKX2.2, and NKX6.1 genes. Four of them have never been described in literature before. The frequency of occurrence of two of them in the RFX6 gene significantly differed in relation to the healthy population. The analysis of segregation in the family did not reveal that they were the only cause of the disease phenotype. CONCLUSIONS: The very-rare variants indicated in this study show that this type of research on large population groups may help in the future for better understanding and more accurate diagnostics of extremely rare forms of MODY.

Evaluation of Changes to the Oral Microbiome Based on 16S rRNA Sequencing among Children Treated for Cancer.

A child's mouth is the gateway to many species of bacteria. Changes in the oral microbiome may affect the health of the entire body. The aim of the study was to evaluate the changes in the oral microbiome of childhood cancer survivors. Saliva samples before and after anti-cancer treatment were collected from 20 patients aged 6-18 years, diagnosed de novo with cancer in 2018-2019 (7 girls and 13 boys, 7.5-19 years old at the second time point). Bacterial DNA was extracted, and the microbial community profiles were assessed by 16S rRNA sequencing. The relative abundances of Cellulosilyticum and Tannerella genera were found to significantly change throughout therapy (p = 0.043 and p = 0.036, respectively). However, no differences in the alpha-diversity were observed (p = 0.817). The unsupervised classification revealed two clusters of patients: the first with significant changes in Campylobacter and Fusobacterium abundance, and the other with change in Neisseria. These two groups of patients differed in median age (10.25 vs. 16.16 years; p = 0.004) and the length of anti-cancer therapy (19 vs. 4 months; p = 0.003), but not cancer type or antibiotic treatment.

Clinical use of NGS data from the targeted gene panel for mitochondrial diseases screening.

BACKGROUND AND OBJECTIVE: Mitochondrial diseases are a frequent cause of inherited genetic disorders caused by mutations in both the mitochondrial and nuclear human genome. The new technique of high-throughput sequencing, which is used more and more frequently around the world, is most often focused on nuclear DNA. In some cases, such data after proper IT processing could also allow to determine alterations in mtDNA genome. In our work, we want to verify that off-target reads from targeted gene panels are sufficient data to determine pathogenic variants in the mitochondrial genome. METHODS: We analyzed 50 patients who underwent routine diagnostics with the Illumina's TruSight One Sequencing Panel. In the entire bioinformatic analysis process, we have used only free, user-friendly and generally available online tools that do not require specialized IT knowledge. RESULTS: Most of the data obtained were suitable for determining the presence of homoplasmic variants in mtDNA; 84% of the data met the minimum 20-fold coverage requirement as defined in the scientific literature for clinical data. We managed to identify 16 pathogenic variants in the examined genetic material (mtDNA) according to the ClinVar database. CONCLUSIONS: In conclusion, we have outlined that off-target reads from targeted gene panel (TruSight One Sequencing Panel) may also be suitable for determining potentially pathogenic homoplasmic variants in mtDNA. We also described a simple pipeline based only on free tools available online. Introducing such a pipeline into a standard procedure of clinical units which carry out such research undoubtedly can extend the diagnostic potential by information about mtDNA, especially when it is based on purely free tools that do not require specialized bioinformatic knowledge.

BRG1 Activates Proliferation and Transcription of Cell Cycle-Dependent Genes in Breast Cancer Cells.

Cancer malignancy is usually characterized by unlimited self-renewal. In some types of advanced tumors that are rapidly dividing, gene expression profiles depict elevations in pro-proliferative genes accompanied by coordinately elevated transcription of factors responsible for removal of DNA lesions. In our studies, fast proliferating breast cancer cell lines (MDA-MB-231 and MCF7), BRG1, a component of the SWI/SNF complex, emerges as an activator of functionally-linked genes responsible for activities such as mitotic cell divisions and DNA repair. Products of at least some of them are considerably overrepresented in breast cancer cells and BRG1 facilitates growth of MCF7 and MDA-MB-231 cell lines. BRG1 occurs at the promoters of genes such as CDK4, LIG1, and NEIL3, which are transcriptionally controlled by cell cycle progression and highly acetylated by EP300 in proliferating cells. As previously documented, in dividing cells BRG1 directly activates gene transcription by evicting EP300 modified nucleosomes from the promoters and, thereby, relaxing chromatin. However, the deficiency of BRG1 or EP300 activity for 48 h leads to cell growth arrest and to chromatin compaction, but also to the assembly of RB1/HDAC1/EZH2 complexes at the studied cell cycle-dependent gene promoters. Epigenetic changes include histone deacetylation and accumulation of H3K27me trimethylation, both known to repress transcription. Cell cycle arrest in G1 by inhibition of CDK4/6 phenocopies the effect of the long-term BRG1 inhibition on the chromatin structure. These results suggest that BRG1 may control gene transcription also by promoting expression of genes responsible for cell cycle progression in the studied breast cancer cells. In the current study, we show that BRG1 binding occurs at the promoters of functionally linked genes in proliferating breast cancer cells, revealing a new mechanism by which BRG1 defines gene transcription.

Analysis of maternal lineage structure of individuals from chamber graves placed in medieval cemetery in Kaldus, Central Poland.

The beginning of the early Middle Ages period in Poland (10th-14th century) has been widely debated in the context of an active demographic inflow from other countries and its contribution to the creation of the new country. Finding chamber graves which are considered typical for the Scandinavian ethnic group in a few cemeteries in Poland has become the basis for the anthropological inference on the potential participation of North European people in forming the social elite of medieval Poland. However, the question of whether this fact was the result of presence of people from other countries lacks an unambiguous answer. We attempted to isolate ancient DNA from the medieval necropolis in Kaldus where several chamber graves have been found and analysed the genetic diversity of maternal lineage of this population. We analysed the HVR I fragment and coding regions to assess the mitochondrial DNA haplogroup. We have identified a few relatively rare haplogroups (A2, T2b4a, HV, K1a11, J2b1a, and X2) which were previously found in early medieval sites in Norway and Denmark. Obtained results might suggest genetic relation between the people of Kaldus and past northern Europe populations. Present and further research can undoubtedly shed new light on the aspect of the formation of the early medieval Polish population.

PARP1-LSD1 functional interplay controls transcription of SOD2 that protects human pro-inflammatory macrophages from death under an oxidative condition.

The function of macrophages makes them vulnerable to several sources of stress and damage, and thus there is a considerable requirement for some form of resilient molecular defence. Differentiation of human macrophages and their further pro-inflammatory (M1) polarization with bacterial endotoxin is associated with increased transcription of PARP1 and SOD2. The latter gene responded immediately to LPS with high NFκB-dependent expression rate, and the resulting enzyme made M1 macrophages resistant to hydrogen peroxide-induced oxidative stress and associated cell death. LPS-induced recruitment of RELA to SOD2 promoter was accompanied by release of PARP1 and LSD1 from chromatin and increased H3K4 di- and tri-methylation. PARP1 dissociation from SOD2 promoter occurred at an early stage of SOD2 transcriptional activation. This event contributed to the termination of mRNA synthesis at a later stage of macrophage polarization by allowing LSD1 to rebind to the SOD2 promoter. LSD1 removed transcription-promoting methylation of H3K4 and led to displacement of RELA. Analysis of temporal changes at the SOD2 promoter indicated a direct mutual interdependence between PARP1, LSD1, H3K4 methylation and the ongoing SOD2 transcription, which correlated positively with both PARP1 abundance on the chromatin and dimethylation of H3K4, but negatively with LSD1 and chromatin compaction in LPS-treated macrophages. Deficiency of LSD1 activity and maintenance of PARP1 at the SOD2 promoter substantially upregulated SOD2 level, thereby further increasing resistance of M1 macrophages to hydrogen peroxide. Inhibitors of LSD1 and PARP1 poisons that capture the latter enzyme on the chromatin seem to be prosurvival molecular tools protecting polarized macrophages from certain pro-oxidative conditions.

EP300-HDAC1-SWI/SNF functional unit defines transcription of some DNA repair enzymes during differentiation of human macrophages.

Differentiation of human macrophages predisposes these cells to numerous tasks, i.e. killing invading pathogens, and this entails the need for enhanced intracellular defences against stress, including conditions that may increase DNA damage. Our study shows that expression of DNA repair enzymes, such as PARP1, BRCA1 and XRCC1, are activated during macrophage development by the SWI/SNF chromatin remodelling complex, which serves as a histone acetylation sensor. It recognises and displaces epigenetically marked nucleosomes, thereby enabling transcription. Acetylation is controlled both in monocytes and macrophages by the co-operation of EP300 and HDAC1 activities. Differentiation modulates the activities of individual components of EP300-HDAC1-SWI/SNF functional unit and entails recruitment of PBAF to gene promoters. In monocytes, histone-deacetylated promoters of repressed PARP1, BRCA1 and XRCC1 respond only to HDAC inhibition, with an opening of the chromatin structure by BRM, whereas in macrophages both EP300 and HDAC1 contribute to the fine-tuning of nucleosomal acetylation, with HDAC1 remaining active and the balance of EP300 and HDAC1 activities controlling nucleosome eviction by BRG1-containing SWI/SNF. Since EP300-HDAC1-SWI/SNF operates at the level of gene promoters characterized simultaneously by the presence of E2F binding site(s) and CpG island(s), this allows cells to adjust PARP1, BRCA1 and XRCC1 transcription to the differentiation mode and to restart cell cycle progression. Thus, mutual interdependence between acetylase and deacetylase activities defines the acetylation-dependent code for regulation of histone density and gene transcription by SWI/SNF, notably on gene promoters of DNA repair enzymes.

PARP1 promoter links cell cycle progression with adaptation to oxidative environment.

Although electrophiles are considered as detrimental to cells, accumulating recent evidence indicates that proliferating non-cancerous and particularly cancerous cells utilize these agents for pro-survival and cell cycle promoting signaling. Hence, the redox shift to mild oxidant release must be balanced by multiple defense mechanisms. Our latest findings demonstrate that cell cycle progression, which dictates oxidant level in stress-free conditions, determines PARP1 transcription. Growth modulating factors regulate CDK4/6-RBs-E2Fs axis. In cells arrested in G1 and G0, RB1-E2F1 and RBL2-E2F4 dimers recruit chromatin remodelers such as HDAC1, SWI/SNF and PRC2 to condense chromatin and turn off transcription. Release of retinoblastoma-based repressive complexes from E2F-dependent gene promoters in response to cell transition to S phase enables transcription of PARP1. This enzyme contributes to repair of oxidative DNA damage by supporting several strand break repair pathways and nucleotide or base excision repair pathways, as well as acting as a co-activator of transcription factors such as NRF2 and HIF1a, which control expression of antioxidant enzymes involved in removal of electrophiles and secondary metabolites. Furthermore, PARP1 is indispensible for transcription of the pro-survival kinases MAP2K6, ERK1/2 and AKT1, and for maintaining MAPK activity by suppressing transcription of the MAPK inhibitor, MPK1. In summary, cell cycle controlled PARP1 transcription helps cells to adapt to a pro-oxidant redox shift.

Searching for signals of recent natural selection in genes of the innate immune response - ancient DNA study.

The last decade has seen sharp progress in the field of human evolutionary genetics and a great amount of genetic evidence of natural selection has been provided so far. Since host-pathogen co-evolution is difficult to trace due to the polygenic nature of human susceptibility to microbial diseases, of particular interest is any signal of natural selection in response to the strong selective pressure exerted by pathogens. Analysis of ancient DNA allows for the direct insight into changes of a gene pool content over time and enables monitoring allele frequency fluctuations. Among pathogenic agents, mycobacteria are proved to have remained in an intimate, long-lasting relation with humans, reflected by the current high level of host resistance. Therefore, we aimed to investigate the prevalence of several polymorphisms within innate immune response genes related to susceptibility to mycobacterial diseases (in SLC11A1, MBL2, TLR2, P2RX7, IL10, TNFA) in time series data from North and East Poland (1st-18th century AD, n = 207). The comparison of allele frequencies over time revealed a predominant role of genetic drift in shaping past gene pool of small, probably isolated groups, which was explained by the high level of population differentiation and limited gene flow. However, the trajectory of frequency fluctuations of two SNPs suggested the possibility of their non-neutral evolution and the results of applied forward simulations further strengthened the hypothesis of natural selection acting on those loci. However, we observed an unusual excess of homozygosity in the profile of several SNPs, which pinpoints to the necessity of further research on temporally and spatially diverse samples to support our inference on non-stochastic evolution, ideally employing pathway-based approaches. Nevertheless, our study confirms that time series data could help to decipher very recent human adaptation to life-threatening pathogens and assisting demographic events.

Author Correction: Downregulation of PARP1 transcription by promoter-associated E2F4-RBL2-HDAC1-BRM complex contributes to repression of pluripotency stem cell factors in human monocytes.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Presence of archaea and selected bacteria in infected root canal systems.

Infections of the root canal have polymicrobial etiology. The main group of microflora in the infected pulp is bacteria. There is limited data that archaea may be present in infected pulp tissue. The aim of this study was to check the prevalence of archaea in necrotic root canal samples obtained from patients with primary or post-treatment infection. The prevalence of selected bacteria species (Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Synergistes sp.) in necrotic samples was evaluated as well. Sixty-four samples from root canal were collected for DNA and RNA extraction. A PCR assay based on the 16S rRNA gene was used to determine the presence of archaea and selected bacteria. Of the 64 samples, 6 were analyzed by semiquantitative reverse transcription PCR to estimate expression profiles of 16S rRNA, and another 9 were selected for direct sequencing. Archaea were detected in 48.4% samples. Statistical analysis indicated a negative association in coexistence between archaea and Treponema denticola (P < 0.05; Pearson's χ2 test). The main representative of the Archaea domain found in infected pulp tissue was Methanobrevibacter oralis. Archaea 16S rRNA gene expression was significantly lower than Synergistes sp., Porphyromonas gingivalis, and Tannerella forsythia (P < 0.05; Student's t test). Thus, it can be hypothesized that archaea may participate in the endodontic microbial community.

Origin of the ornamented bâton percé from the Golebiewo site 47 as a trigger of discussion on long-distance exchange among Early Mesolithic communities of Central Poland and Northern Europe.

This article describes evidence for contact and exchange among Mesolithic communities in Poland and Scandinavia, based on the interdisciplinary analysis of an ornamented bâton percé from Golebiewo site 47 (Central Poland). Typological and chronological-cultural analyses show the artefact to be most likely produced in the North European Plain, during the Boreal period. Carbon-14 dating confirms the antiquity of the artefact. Ancient DNA analysis shows the artefact to be of Rangifer tarandus antler. Following this species designation, a dispersion analysis of Early-Holocene reindeer remains in Europe was conducted, showing this species to exist only in northern Scandinavia and north-western Russia in this period. Therefore, the bâton from Golebiewo constitutes the youngest reindeer remains in the European Plain and south-western Scandinavia known to date. An attempt was made to determine the biogeographic region from which the antler used to produce the artefact originates from. To this end, comprehensive δ18O, δ13C and δ15N isotope analyses were performed. North Karelia and South Lapland were determined as the most probable regions in terms of isotopic data, results which correspond to the known distribution range of Rangifer tarandus at this time. In light of these finds, the likelihood of contact between Scandinavia and Central Europe in Early Holocene is evaluated. The bâton percé from Golebiewo is likely key evidence for long-distance exchange during the Boreal period.

Ancient DNA analysis might suggest external origin of individuals from chamber graves placed in medieval cemetery in Pien, Central Poland.

ABSTRACT: The participation of immigrants during early days in Poland of Piast's dynasty is a debated issue among archaeologists and anthropologists alike. Such hypotheses were formulated on the basis of, amongst others, the discovery of early medieval chamber graves characterized by construction features typical of the Scandinavian culture area. Archaeological and anthropological studies to date have not provided an unequivocal answer as to whether the individuals interred in those graves were autochthons who adopted a different burial rite, or perhaps immigrants from foreign lands. To characterize the gene pool of this population we analyzed the C/T allele of the nuclear gene LCT-13910 as well as fragments of the mitochondrial genome from individuals buried in very richly furnished chamber graves at the medieval cemetery in Pien. The obtained results for the nuclear allele and mtDNA do not corroborate the Scandinavian origin of the analyzed population. Moreover, we did not find haplogroup I, which is the one typical of populations that historically inhabited the north of Europe; and the frequency of the LCT-13910 T allele was similar to that of past and present Polish populations. On the other hand, we identified the atypical haplogroup C5c1, which suggests Asian origin of the studied individuals and confirms our previous reports concerning ancient human migrations from Asia to the territory of present-day Poland. While our findings do not conclusively disprove a Scandinavian lineage of the studied population, they certainly shed some new light on the origin of the individuals buried in chamber graves, which may be very different from the one initially proposed by archaeologists.

Downregulation of PARP1 transcription by promoter-associated E2F4-RBL2-HDAC1-BRM complex contributes to repression of pluripotency stem cell factors in human monocytes.

Differentiation of certain cell types is followed by a downregulation of PARP1 expression. We show that the reduction in the abundance of PARP1 in hematopoietic progenitor cells and monocytes is tightly controlled by the cell cycle. The differentiation-associated cell cycle exit induces E2F1 replacement with E2F4 at the PARP1 promoter and the assembly of an E2F4-RBL2-HDAC1-BRM(SWI/SNF) repressor complex which deacetylates nucleosomes and compacts chromatin. In G1 arrested cells, PARP1 transcription is reduced by the recruitment of E2F1-RB1-HDAC1-EZH2(PRC2)-BRM/BRG1(SWI/SNF), which additionally trimethylates H3K27 and causes an even higher increase in nucleosome density. The re-establishment of an active chromatin structure by treating post-mitotic monocytes with the HDAC inhibitor and G1 arrested cells with a combination of HDAC and EZH2 inhibitors restores PARP1 expression completely but does not affect the interaction between the components of the repressor complex with chromatin. This suggests that RB1 and RBL2, as well as PRC2, SWI/SNF and HDAC1, do not interfere with the transcription machinery. Interestingly, reinstatement of PARP1 expression by the silencing of RBL2 or by the inhibition of HDACs in monocytes and by transfection with the PARP1 expression vector in differentiated THP-1 cells substantially increased transcription of pluripotency stem cell factors such as POU5F1, SOX2 and NANOG.

Cholelithiasis - always infected?

This study aims to present results regarding the presence and identification of bacterial strains found in bile and gallstones located in the gallbladder and bile ducts in patients operated on due to cholelithiasis. MATERIALS AND METHODS: Bacterial culture was evaluated in 92 patients. There were 54 women (59%) and 38 men (41%) who underwent surgery on account of cholelithiasis and /or gallstones in bile ducts between 2013 and 2014. Bile and gallstone samples were cultured intraoperatively for bacteria; bacterial strains were identified, and their sensitivity to antibiotics was determined. Molecular methods (NGS and Sanger method) were used to separate bacterial strains in one of the gallbladder stones and the results were compared with bacterial strains grown from the bile. RESULTS: Bile cultures were positive in 46 patients that is, 50% of the study group. The following bacteria strains were grown: Enterococcus spp. (44%), Escherichia coli (37%) and Klebsiella spp. (35%). Candidiasis accompanied by bacterial infection was detected in 7 patients (15%). Molecular testing of gallstones revealed DNA of Enterococcus spp., Escherichia spp., Streptococcus spp. and Clostridium spp. In the bile culture of the same patient Enterococcus spp. (avium and faecalis) was detected. Conclusion 1. More than one pathogen was grown on samples obtained from 31 patients (70%) with bile infection. 2. The most common pathogens include Enterococcus spp., Escherichia coli and Klebsiella spp. 3. Bacterial infections are often accompanied by a fungal infection (Candida albicans) 4. Bacterial strains grown from a gallstone sample partially corresponded with strains identified in the bile of the same patient.

Analysis of medieval mtDNA from Napole cemetery provides new insights into the early history of Polish state.

Contemporary historical anthropology and classical archaeology are concerned not only with such fundamental issues as the origins of ancient human populations and migration routes, but also with the formation and development of inter-population relations and the mixing of gene pools as a result of inter-breeding between individuals representing different cultural units. The contribution of immigrants to the analysed autochthonous population and their effect on the gene pool of that population has proven difficult to evaluate with classical morphological methods. The burial of one individual in the studied Napole cemetery located in central Poland had the form of a chamber grave, which is typical of Scandinavian culture from that period. However, this fact cannot be interpreted as absolute proof that the individual (in the biological sense) was allochtonous. This gives rise to the question as to who was actually buried in that cemetery. The ancient DNA results indicate that one of the individuals had an mtDNA haplotype typical of Iron Age northern Europe, which suggests that he could have arrived from that area at a later period. This seems to indirectly confirm the claims of many anthropologists that the development of the early medieval Polish state was significantly and directly influenced by the Scandinavians.