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Using the disc instability model for dwarf novae and soft X-ray transients, we investigate the stability of accretion discs in long-period binary systems. We simulate outbursts resulting from this thermal-viscous instability for two symbiotic systems, RS Ophiuchi and Z Andromedae. The outburst properties deduced from our simulations suggest that, although the recurrent nova events observed in RS Oph are caused by thermonuclear runaway at the white dwarf surface, these runaways are triggered by accretion disc instabilities. In quiescence, the disc builds up its mass, and it is only during the disc-instability outburst that mass is accreted on to the white dwarf at rates comparable to or larger than the mass-transfer rate. For a mass-transfer rate in the range 10−8to |$10^{-7} \, {\rm M_{\odot}}$| yr−1, the accretion rate and the mass accreted are sufficient to lead to a thermonuclear runaway during one of a series of a few dwarf nova outbursts, which are barely visible in the optical but easily detectable in the X-rays. In the case of Z And, persistent irradiation of the disc by the very hot white dwarf surface strongly modifies the dwarf nova outburst properties, making them significant only for very high mass-transfer rates, of the order of |$10^{-6} \, {\rm M_{\odot}}$| yr−1, much higher than the expected secular mean in this system. It is thus likely that the so-called 'combination nova' outburst observed in the years 2000 to 2002 was triggered not by a dwarf-nova instability but by a mass-transfer enhancement from the giant companion, leading to an increase in nuclear burning at the accreting white dwarf surface. [ABSTRACT FROM AUTHOR]

Purpose: Perilesional edema is a serious and well- known complication after stereotactic radiotherapy. The aim was to evaluate the risk of edema after treatment and the assessment of its dynamics in patients treated with stereotactic radiosurgery. Methods: 107 patients underwent intracranial stereotactic radiotherapy. Our diversed group comprised 34 patients with arteriovenous malformations (29%), 38 meningiomas (35%), 16 metastatic tumors (15%), 16 acustic neuromas (15%), 3 cavernomas (3%), 2 anaplastic astocytomas (2%), anaplastic oligoastrocytomas (2%). Each edema was carefully delineated in MRI T2 FLAIR sequence in 0,6,12,18,24,30 and 38 months after treatment. We divided lesions in terms of their presence above (80 patients) and below (32 patients) the Frankfurter line. Results: New development or aggravation of perilesional edema was observed in 17% patients in posttreatment evaluation. The largest volume of edema occurred at 6 months (mean 7.2, SD 1.2) post radiosurgery. Comparing the location of lesions, the incidence of the development of post-SRS perilesional edema was 5.1 (1,06-24,53) times higher in patients above the Frankfurter line. There was no significant relation between the development of edema and age, PTV size, number of beams and diagnosis (p = 0.07) Conlusions: Radiosurgery associated edema develops within 6 months after treatment and decreases over time. Perilesional edema can deteriorate neurological condition, therefore it should be treated . Edema presence is much more likely when the lesions are located above the Frankfurter line. Disclosure: No significant relationships. [ABSTRACT FROM AUTHOR]

Rapid bursts at optical wavelengths have been reported for several accreting white dwarfs. In these bursts, the optical luminosity can increase by up to a factor of 30 in less than an hour, before fading on time-scales of several hours, and the energy release can reach ~1039 erg ('micronovae'). Several systems have also shown these bursts to be semirecurrent on time-scales of days to months, and the temporal profiles of these bursts strongly resemble those observed in Type-I X-ray bursts in accreting neutron stars. It has been suggested that the observed micronovae may be the result of localized thermonuclear runaways in the surface layers of accreting white dwarfs. Here we propose a model in which the magnetic confinement of accretion streams on to the accreting magnetic white dwarf may trigger localized thermonuclear runaways. The model proposed to trigger micronovae appears to favour magnetic systems with both a high white dwarf mass and a high mass-transfer rate. [ABSTRACT FROM AUTHOR]

The LIGO/Virgo gravitational-wave observatories have detected at least 50 double black hole (BH) coalescences. This sample is large enough to have allowed several recent studies to draw conclusions about the implied branching ratios between isolated binaries versus dense stellar clusters as the origin of double BHs. It has also led to the exciting suggestion that the population is highly likely to contain primordial BHs. Here we demonstrate that such conclusions cannot yet be robust because of the large current uncertainties in several key aspects of binary stellar evolution. These include the development and survival of a common envelope, the mass and angular-momentum loss during binary interactions, mixing in stellar interiors, pair-instability mass loss, and supernova outbursts. Using standard tools such as the rapid population synthesis codes StarTrack and COMPAS and the detailed stellar evolution code MESA, we examine as a case study the possible future evolution of Melnick 34, the most massive known binary star system (with initial component masses of 144 M ⊙ and 131 M ⊙). We show that, despite its fairly well-known orbital architecture, various assumptions regarding stellar and binary physics predict a wide variety of outcomes: from a close BHâ€"BH binary (which would lead to a potentially detectable coalescence), through a wide BHâ€"BH binary (which might be seen in microlensing observations), or a Thorneâ€"Ĺ»ytkow object, to a complete disruption of both objects by a pair-instability supernova. Thus, because the future of massive binaries is inherently uncertain, sound predictions about the properties of BHâ€"BH systems formed in the isolated binary evolution scenario are highly challenging at this time. Consequently, it is premature to draw conclusions about the formation channel branching ratios that involve isolated binary evolution for the LIGO/Virgo BHâ€"BH merger population. [ABSTRACT FROM AUTHOR]

Epithelial chemosensory cells in hollow organs, also known as tuft cells, were implicated in tumorigenesis, including a tuft cell-like small cell lung carcinoma. Expression of the POU2F3 transcription factor is a marker of tuft cell lineage. However, tuft cell development, differentiation, and proliferation are controlled by the expression of the complex formed by POU2F3 and POU2AF2 or POU2AF3 transcriptional coactivators. A cohort of epithelial (n=6064) and mesenchymal/neuroectodermal (n=2730) tumors was screened for POU2F3 expression by immunohistochemistry. Variable immunoreactivity ranging from diffuse to scattered positive cells was found in ∼12.4% of epithelial and 4.6% of mesenchymal/neuroectodermal tumors. Cases with predominantly diffuse or patchy POU2F3 positivity representing various types of malignant tumors (n=43) were selected for further study, including POU2AF2 immunohistochemistry. Thirteen of 15 tumors with neuroendocrine differentiation originating from the lung, colon, head and neck, skin, and bladder revealed diffuse POU2F3 positivity. Most of those tumors (n=9) co-expressed POU2AF2, usually extensively. Seven squamous and basal cell carcinomas from the oral cavity, skin, lung, and thymus with diffuse POU2F3 immunostaining except one, lacked POU2AF2 expression. Other variably POU2F3-positive carcinomas (n=13) from the colon, pancreas, liver, kidney, testis, endometrium, ovary, and breast lacked POU2AF2 immunoreactivity. All POU2F3-positive mesenchymal and neuroectodermal tumors (n=8), including synovial sarcoma, solitary fibrous tumor, glioblastoma, Wilms tumor, and melanoma were POU2AF2-negative. POU2F3 expression is a highly sensitive but nonspecific indicator of tuft cell differentiation. Co-expression of POU2F3 and POU2AF2 appears to be a more specific marker, although it may not pinpoint tumors driven by the POU2F3-POU2AF3 complex., Competing Interests: Conflicts of Interest and Source of Funding: Supported as a part of NCI’s intramural research program. The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

SATB2 has been reported to be highly specific for lower gastrointestinal tract tumors. On the basis of its ileum-colon conversion effects, which involve the activation of colonic genes in cooperation with CDX2 and HNF4A, we hypothesized that SATB2 and CDX2 might define the characteristics of colorectal cancers (CRCs). In the present study, the clinicopathologic and immunohistochemical characteristics of 269 CRCs were analyzed according to SATB2 and CDX2 expression. CRCs with SATB2- and/or CDX2- phenotypes showed associations with poorly differentiated histotypes ( P <0.00001), mucus production ( P =0.0019), and mismatch repair-deficient phenotypes ( P <0.00001). SATB2-/CDX2- CRCs were significantly associated with CK20-negativity, with or without CK7 expression ( P <0.00001), as well as with MUC5AC-positivity ( P <0.00001), and CD10-negativity ( P =0.00047). Negativity for SATB2 or CDX2 was associated with the expression of PD-L1 in both all CRC ( P <0.00001) and mismatch repair-proficient CRC ( P =0.000091). Multivariate Cox hazard regression analysis identified negativity for SATB2 and/or CDX2 as potential independent risk factors for patients with CRC. Regarding the diagnostic utility of SATB2, all of the 44 CRC metastases could be diagnosed as colorectal in origin if the immunohistochemical phenotypes (including CK7, CK20, and p53) of the primary lesions and patient history were considered. Among the other 684 tumors, we were unable to distinguish a case of CK7-/CK20+/CDX2+/SATB2+ ovarian mucinous cystadenocarcinoma from metastatic CRC without the patient history and clinical information., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Schlafen 11 (SLFN11), a DNA/RNA helicase, acts as a regulator of cellular response to replicative stress and irreversibly triggers replication block and cell death. Several preclinical in vitro studies and clinical trials established that SLFN11 expression predicts outcomes in patients with advanced cancer treated with DNA-damaging chemotherapeutics and more recently with poly(ADP-ribose) polymerase inhibitors. SLFN11 expression status remains unknown in many cancer types, especially in mesenchymal tumors. This study evaluated a cohort of well characterized 3808 epithelial and 2850 mesenchymal and neuroectodermal tumors for SLFN11 expression using immunohistochemistry. Nuclear SLFN11 expression was rare in some of the most common carcinomas, for example, hepatocellular (1%), prostatic (2%), colorectal (5%), or breast (16%) cancers. In contrast, other epithelial tumors including mesotheliomas (92%), clear cell renal cell carcinomas (79%), small cell lung cancers (76%), squamous cell carcinomas of the tonsil (89%) and larynx (71%), or ovarian serous carcinomas (69%) were mostly SLFN11-positive. Compared with epithelial malignancies, SLFN11 expression was overall higher in neuroectodermal and mesenchymal tumors. Most positive entities included desmoplastic small round cell tumor (100%), Ewing sarcoma (92%), undifferentiated sarcoma (92%), solitary fibrous tumor (91%), dedifferentiated liposarcoma (89%), synovial sarcoma (86%), and malignant peripheral nerve sheath tumor (85%). Also, this study identifies tumors with potentially worse response to DNA-damaging drugs including antibody drug conjugates due to the absence of SLFN11 expression. Such entities may benefit from alternative treatments or strategies to overcome SLFN11 deficiency-related drug resistance. Our approach and results should serve as a foundation for future biomarker-associated clinical trials., Competing Interests: Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Competing Interests: The authors have no relevant financial interest in the products or companies described in this article.

Microplastics have the capacity to accumulate in soil due to their high resistance to degradation, consequently altering soil properties and influencing plant growth. This study focused on assessing the impact of various types and doses of microplastics on beech seedling growth. In our experiment, we used polypropylene and styrene granules with diameter of 4.0 mm in quantities of 2.5% and 7%. The hypothesis was that microplastics significantly affect seedlings' nutritional status and growth characteristics. The research analysed seedlings' nutrition, root morphological features, above-ground growth, and enzymatic activity in the substrate. Results confirmed the importance of microplastics in shaping the nutritional status of young beech trees. Microplastic type significantly impacted N/P and Ca/Mg stoichiometry, while microplastic quantity influenced Ca/Al and Ca + K + Mg/Al stoichiometry. Notably, only in the case of root diameter were significantly thicker roots noted in the control variant, whereas microplastics played a role in shaping the leaves' characteristics of the species studied. The leaf area was significantly larger in the control variant compared to the variant with polypropylene in the amount of 2.5% and styrene in the amount of 7%. Additionally, the study indicates a significant impact of microplastics on enzyme activity. In the case of CB and SP, the activity was twice as high in the control variant compared to the variants with microplastics. In the case of BG, the activity in the control variant was higher in relation to the variants used in the experiment. Research on the impact of microplastics on the growth of beech seedlings is crucial for enhancing our understanding of the effects of environmental pollution on forest ecosystems. Such studies are integral in shaping forestry management practices and fostering a broader public understanding of the ecological implications of plastic pollution., (© 2024. The Author(s).)

Background: We report a nasal cavity unusual perivascular epithelioid cell tumor (PEComa) mimicking mucosal melanoma., Methods: Immunohistochemistry was performed using BenchMark Ultra and panel of antibodies. The Ion Torrent platform and Ion AmpliSeq cancer hotspot panel were utilized for DNA genotyping. Target-specific RNA libraries for the detection of fusion transcripts were constructed using Archer Universal RNA Reagent Kit v2 and Archer FusionPlex Solid Tumor panel and sequenced on the MiSeqDx instrument., Results: The tumor, diagnosed in 46-year-old female, was composed of spindle cells, and lacked pigmentation. Immunohistochemically, it showed a patchy HMB-45 positivity. Other melanocytic markers (S100 protein, Melan-A, SOX10) were negative. The tumor cells were weakly positive for KIT (CD117) while negative for smooth muscle actin, pancytokeratin cocktail (AE1/AE3), and synaptophysin. Diagnosis of primary sinonasal tract mucosal melanoma was favored. Additional molecular studies detected PRCC :: TFE3 fusion as the sole genetic change, and suggested the diagnosis of unusual PEComa. Previously, TFE3 fusions were reported in a subset of PEComas but not in melanomas, while PRCC involvement has only been documented once in an ocular PEComa. Immunohistochemistry revealed strong nuclear TFE3 expression concordant with the molecular findings., Conclusions: This report emphasis the importance of molecular testing in the differential diagnosis between PEComa and melanoma, especially when the tumor arises in a site typical of melanoma but showing an unusual morphology and immunophenotype. The detection of TFE3 fusion transcripts suggested the diagnosis of SNT PEComa, although it cannot be excluded that this and similar tumors represent a distinct diagnostic category., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Deadwood is an important element of forest ecosystems that affects many of its components, including the soil environment. Our research is an attempt to determine the role of decaying wood in shaping the properties of forest soils in mountain ecosystems. The aim of our research was to present the influence of beech deadwood on physicochemical properties and microbiological diversity of soils. The research was carried out in the Baba Góra Massif at its northern exposure. The research plots were established in the altitude gradient at 600, 800 and 1000 m above sea level. On each plot, samples were taken from decaying wood, from the soil directly under the decaying log, and a soil sample 1 m from the log as a control. We determined the basic properties of the samples, that is pH, C and N concentration and lignin content. The enzymatic activity and additionally, the taxonomic composition of soil bacterial and fungal communities was determined in the collected samples. Our research indicates the important role of decaying beech wood in shaping the properties of forest soils. We noted a positive effect of decaying wood on the properties of the tested soils. Soils affected by deadwood were characterized by significantly higher pH, C and N concentrations compared to control soils, regardless of their location in the altitude gradient. Additionally, we found that soils affected by decaying wood are characterized by a different composition of microorganisms regardless of their location in the altitude gradient. In control soil the fungal and bacterial alpha diversity were lowest compared with the deadwood and soil under the influence of deadwood. Our results may have practical applications in the management of forest ecosystems. The presented results indicate the possibility of leaving deadwood in order to improve its basic physicochemical properties and increase microbial diversity., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ewa Błońska reports financial support was provided by National Science Centre, Poland., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background/Objectives: Preferentially expressed antigen in melanoma (PRAME), a member of the cancer testis antigen family, is a promising target for cancer immunotherapy. Understanding the epigenetic mechanisms involved in the regulation of PRAME expression might be crucial for optimizing anti-PRAME treatments. Methods: Three malignancies of different lineages (sinonasal melanoma, testicular seminoma, and synovial sarcoma), in which immunohistochemical (IHC) reactivity for PRAME is a common yet variable feature, were studied. The expression of PRAME, ten-eleven translocation demethylase 1 (TET1), and DNA methyltransferase (DNMT) 3A and 3B were evaluated using immunohistochemistry. Moreover, the expression of two epigenetic marks, 5-hydroxymethylcytosine (5hmC) and histone 3 acetylation (H3ac), was tested. Results: All PRAME-positive tumors expressed medium-to-high levels of H3ac but differed considerably with respect to other markers. In seminomas, PRAME expression correlated with TET1, but in melanomas and synovial sarcomas, it correlated with both DNMTs and DNMT3A, respectively. Conclusions: PRAME expression was not determined by a balance between the global expression of DNA methylating/demethylating enzymes. However, histone acetylation may be one of the epigenetic mechanisms involved in PRAME regulation. Thus, the therapeutic combination of histone deacetylase inhibitors and PRAME immunotherapy merits further investigation.