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A quantum chemical study on the relative stability of diaminodinitroethylene isomers
No full textThis study aims to investigate the relative stability of the diaminodinitroethylene isomers
(cis, trans, and gem). To achieve this goal, calculations at several levels of theory were
carried out. The B3LYP, PBE0, and CAM-B3LYP functionals, based on density functional
theory (DFT), were used. G4 and MP2 calculations were also executed. All calculation
methods predicted that the gem isomer is the most stable, while the cis isomer is the least
stable. The energy order obtained for the isomers studied was rationalized by analysis of
the detected intramolecular hydrogen bonding, electron delocalization, charge distribution,
and changes in atomic energies in the structures studied. The origins of the superior
stability of the gem isomer are demonstrated and justifie
The impact of H1-H4 receptor antagonists on the levels of selected oxidative stress markers in liver and muscle tissue in an animal model of colitis
No full textZastosowanie przybliżonych metod zwężania sieci tensorowych dla dyskretnych problemów optymalizacyjnych
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No full textEndometrial cancer is the most common gynaecologic malignancy in high-income countries, with a rising incidence largely driven by reproductive factors, obesity, and prolonged exposure to unopposed oestrogens. Although most cases are sporadic, approximately 2–5% are associated with hereditary cancer syndromes, of which Lynch syndrome represents the most important contributor. Lynch syndrome results from germline mutations in DNA mismatch repair (MMR) genes and is associated with a substantially increased lifetime risk of endometrial cancer, reaching up to 71% in carriers of MutS homologue 6 (MSH6) mutations. Hereditary cancer predisposition typically follows an autosomal dominant inheritance pattern and may be suspected based on clinical warning signs such as early disease onset, multiple primary malignancies, a strong family history, or the presence of microsatellite instability in tumour tissue. In addition to Lynch syndrome, rarer genetic conditions—including Cowden syndrome (PTEN), Li–Fraumeni syndrome (TP53), polymerase proofreading–associated polyposis (POLE/POLD1), and hereditary breast and ovarian cancer syndromes (BRCA1/2)—also contribute to hereditary endometrial cancer risk. Recognition of these genetic backgrounds is essential for accurate diagnosis, personalised surveillance, and the implementation of targeted preventive and therapeutic strategies. Despite major advances in molecular diagnostics, hereditary endometrial cancer remains frequently underdiagnosed, leading to missed opportunities for cancer prevention among affected individuals and their families. This comprehensive review summarises current evidence on hereditary predispositions to endometrial cancer, with a particular emphasis on Lynch syndrome, and discusses underlying genetic mechanisms, inheritance patterns, diagnostic strategies, and clinical implications for screening, genetic counselling, and treatment optimisation
Probing active galactic nuclei–interstellar medium feedback through extended x-ray emission in ESO 137-G034
No full textWe present a detailed analysis of the X-ray emission of the Compton-thick (CT) active galactic nuclei (AGN) ESO 137-G034 based on deep (∼230 ks) Chandra observations. As in other CT AGNs, the morphology of the emission is elongated, approximately following the [O III] ionization bicone. With spatially resolved spectral modeling, we show that the extended emission within the bicone regions is most readily explained as from a mixture of photoionized gas and shock-heated plasma, reflecting the combined effects of radiative and kinematic AGN feedback. By comparing the morphology of the X-ray emission in narrow spectral bands and that of the 3 cm radio jet, we find suggestive evidence of thermal, possibly shocked emission associated with the SE termination of the radio jet. This interpretation is also supported by the lack of [O III] relative to the 0.3−3.0 keV flux in the inner 3″ (∼600 pc) of the SE cone, which would be consistent with an additional thermal X-ray component on top of the photoionized emission of an outflowing wind. A similar effect is only seen within the inner 1″ (200 pc) of the NW cone. In the radial profile of the [O III]/X-ray flux ratio and the X-ray hardness ratio within the inner ∼3″ (∼600 pc) of the SE cone, we see an asymmetry, with no counterpart in the NW cone. We detect soft extended X-ray emission in the cross cones, which may originate from the interaction of an embedded radio jet with a clumpy interstellar medium. These results highlight the importance of both radiative and mechanical feedback in shaping the circumnuclear environment of ESO 137-G034
Chronological lifespan extension and nucleotide salvage inhibition in yeast by isonicotinamide supplementation
No full textIsonicotinamide (INAM) is an isomer of the precursor nicotinamide (NAM) that stimulates the enzymatic activity of Sir2, an -dependent histone deacetylase from the budding yeast, Saccharomyces cerevisiae. Supplementing INAM into growth media promotes the replicative lifespan (RLS) of this single cell organism by maintaining intracellular homeostasis. INAM also extends yeast chronological lifespan (CLS), but the underlying mechanisms remain largely uncharacterized. To identify cellular pathways potentially impacted by INAM, in this study we perform a chemical genomics screen of the yeast knockout (YKO) collection for mutants sensitized to growth inhibition by INAM. Significant Gene Ontology (GO) terms for candidate genes include transcription elongation factors, metabolic pathways converging on one-carbon metabolism, and de novo purine biosynthesis, collectively suggesting that INAM perturbs nucleotide metabolism. Indeed, INAM causes dose-dependent depletion of intracellular cytidine, uridine, and guanosine, ribonucleosides derived from the breakdown of nucleotide monophosphates (NMPs) via nucleotidases (Phm8, Sdt1, Isn1) or the alkaline phosphatase Pho8. We also find that INAM directly inhibits recombinant nucleotidase activity using cytidine or nicotinamide mononucleotide (NMN) as substrates and inhibits alkaline phosphatase activity quantitated from whole cell extracts. Lastly, we find that Phm8 and Pho8 are specifically required for INAM-induced CLS extension, implicating them as likely functional targets in vivo. Taken together, the findings suggest a model whereby partial impairment of nucleotide and/or salvage pathways by INAM can trigger a hormetic stress response that supports enhanced quiescence during chronological aging
Report : Greentech Polska 2025 : analysis of the Greentech startup sector
No full textRaport GreenTech 2025 powstał z myślą o wszystkich, którym tematy zielonej transformacji nie są obojętne. Dla startupów to źródło wiedzy o rynku, finansowaniu, regulacjach i możliwościach współpracy. Dla korporacji i dużych firm – wgląd w realny potencjał sektora, poparty badaniem startupów, które pokazuje, jak wygląda dzisiejszy rynek innowacji w Polsce. Jednocześnie to inspiracja, gdzie możliwe jest poszukiwanie rozwiązań wspierających własną transformację w kierunku Gospodarki Obiegu Zamkniętego
Search for the most precise diagnosis of monogenic diabetes - the usefulness of short-read NGS method in molecular testing in Polish patients
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