ACUTE MYOCARDITIS IN YOUNG AGE MIMICKING AS ST-ELEVATION MYOCARDIAL INFARCTION: CASE REPORT.

Acute myocarditis remains a diagnostic issue with a wide spectrum of clinical manifestations that could mimic ST-elevation myocardial infarction (STEMI). We present a case of a 26-year-old male with left-sided intense squeezing chest pain associated with elevated troponin, ST-segment elevations, and reduced ejection fraction. The patient was initially suspected of having a STEMI with non-obstructed coronary arteries (MINOCA). However, due to positive pair troponin tests, increased inflammatory markers there was suspected myocarditis and cardiac MRI confirmed this diagnosis. This case highlights the clinical significance of assessment of laboratory markers and cardiac MRI in diagnostics of myocarditis.

In-depth characterization of a new patient-derived xenograft model for metaplastic breast carcinoma to identify viable biologic targets and patterns of matrix evolution within rare tumor types.

Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu·MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell-matrix interactions in rare cancer types using higher passage PDX tissue.

Adhesion-dependent regulation of an A+U-rich element-binding activity associated with AUF1.

Monocyte adherence results in the rapid transcriptional activation and mRNA stabilization of numerous mediators of inflammation and tissue repair. While the enhancer and promoter elements associated with transcriptional activation have been studied, mechanisms linking adhesion, mRNA stabilization, and translation are unknown. GROalpha and interleukin-1beta (IL-1beta) mRNAs are highly labile in nonadhered monocytes but stabilize rapidly after adherence. GROalpha and IL-1beta transcripts both contain A+U-rich elements (AREs) in the 3' untranslated region (UTR) which have been directly associated with rapid mRNA turnover. To determine if the GROalpha ARE region was recognized by factors associated with mRNA degradation, we carried out mobility gel shift analyses using a series of RNA probes encompassing the entire GROalpha transcript. Stable complexes were formed only with the proximal 3' UTR which contained the ARE region. The two slower-moving complexes were rapidly depleted following monocyte adherence but not direct integrin engagement. Deadherence reactivated the two largest ARE-binding complexes and destabilized IL-1beta transcripts. Antibody supershift studies demonstrated that both of these ARE RNA-binding complexes contained AUF1. The formation of these complexes and the accelerated mRNA turnover are phosphorylation-dependent events, as both are induced in adherent monocytes by the tyrosine kinase inhibitor genistein and the p38 MAP kinase inhibitor of IL-1beta translation, SK&F 86002. These results demonstrate that cell adhesion and deadhesion rapidly and reversibly modify both cytokine mRNA stability and the RNA-binding complexes associated with AUF1.

Differential role of tyrosine phosphorylation in adhesion-induced transcription, mRNA stability, and cytoskeletal organization in human monocytes.

Monocyte adhesion resulted in rapid tyrosine phosphorylation and subsequent cytokine mRNA induction. The objective of this study was to determine the role of specific tyrosine phosphorylation events, particularly those involving members of the MAP kinase family, in regulating adhesion-induced cytokine expression. Using nuclear run-on analyses, we demonstrated that on adhesion, monocytes rapidly transcriptionally activated numerous cytokine mRNAs, coincident with the activation of the transcription factors NF-KB and AP-1. Both an inhibitor of tyrosine phosphorylation, genistein, and the cytoplasmic tyrosine phosphatase PTP1B, were unable to prevent adhesion-mediated transcriptional activation. However, both blocked adhesion-induced ERK and JNK but not p38 kinase activation and at the same time decreased the stability of interleukin-1beta (IL-1beta) and IL-8 transcripts. In addition, whereas adhesive events occurred in the presence of genistein and PTP1B, monocyte spreading was markedly inhibited. Our results suggest that the majority of protein phosphorylation events are associated with adhesion-induced cytokine expression through transcript stabilization and cytoskeletal organization. A minority of protein phosphorylation events, not sensitive to genistein or PTP1B exposure, may be instrumental in regulating transcription. Thus the spectrum of protein tyrosine kinases required for transcription appear distinct from those involved in maintaining the stability of some cytokine mRNAs and the integrity of the cytoskeleton to which mRNA destined for translation must be associated.

[Possibility of using fish and amphibians for detecting the carcinogenic action of nitrosomorpholine and its chemical precursors]. / Vozmozhnost' ispol'zovaniia ryb i amfibii dlia vyiavleniia kantserogennogo deistviia nitrozomorfolina i ego khimicheskikh predshestvennikov.

When dissolved in water nitrosomorpholine induced in frogs Rana temporaria and aquarium fish adenomas and cancer, hemocytoblastosis, adenomatous polyps and adenocarcinomas of the intestine, mesenchymomas. A combined action of sodium nitrite and morpholine would induce the tumors concerned, but taken separately NN and M produced only a toxic effect. The morpholine nitration appears to proceed both endogenously and directly in water. It seems rational to use animals of the aqueous medium as an indicator of nitrosoamines and their precursors contamination of hydrosphere.

Genomic footprinting of Mig1p in the MAL62 promoter. Binding is dependent upon carbon source and competitive with the Mal63p activator.

Mig1p inhibits gene expression in glucose by binding the Cyc8p (Ssn6p)-Tup1p repressor to the promoter of glucose-repressible genes. While the binding properties of Mig1p have been studied in vitro and the ability of Mig1p-Cyc8p (Ssn6p)-Tup1p to repress has been studied in vivo, no experiments have measured the effect of a carbon source on the in vivo binding of Mig1p or the effect of bound MIg1p on activator occupancy of the upstream activation sequence (UAS). To obtain this information, we used genomic footprinting to investigate glucose repression of MAL62, a gene that is also regulated by the Mal63p activator. These experiments show that two interrelated mechanisms are involved in the glucose repression of MAL62: 1) competition between the Mal63p activator and Mig1p for DNA binding and 2) modulation of Mig1p binding by the carbon source. Mig1p affects basal MAL62 expression in the absence of Mal63p by binding to a site in the MAL62 promoter and affects Mal63p-dependent synthesis by also inhibiting the access of Mal63p to site 1 in the UASMAL. The binding of Mig1p is increased in glucose and decreased in nonrepressing sugars, but the increased binding in glucose is not due to an increase in the levels of Mig1p.

[Development of tumors in Unio pictorum bivalve mollusks under the influence of N-nitroso compounds]. / Vozniknovenie opukholei u dvustvorchatykh molliuskov Unio pictorum pod vliianiem N-nitrozosoedinenii.

Diethyl- and dimethylnitrosamines dissolved in tank water in doses of 200-400 ppm induced neoplasms of the digestive gland (basophilic cell neoplasms) in 16 of 95 and in 6 of 17 molusco which survived to the time of appearance of the first tumour (38-39 days), and also neoplasms of the hemopoietic system (lymphatic leukemia) in 7 and 1 molluscs, chiefly in combination with tumours of the digestive gland. Methylnitrosoguanidine induced only inflammatory changes at the site of injections. It is of expedience to use the molluscs as a biological indicator of the hydrosphere pollution with chemical carcinogens.

Purification and binding properties of the Mal63p activator of Saccharomyces cerevisiae.

Mal63p is a transcriptional activator for maltose fermentation in Saccharomyces cerevisiae. We have purified it to homogeneity from a yeast strain in which the MAL63 gene is under the control of the GAL1-GAL10 promoter. Purification included fractionation of a whole-cell extract by ion-exchange chromatography, chromatography using both non-specific DNA-affinity (calf thymus), and sequence-specific DNA-affinity chromatography. Mal63p activity was assayed by its binding to a fragment of the MAL61-MAL62 promoter, using both filter-binding and electrophoretic-mobility shift assays. DNase-I footprinting identified a new binding site (site 3) between the two previously known sites (sites 1 and 2). Mal63p is a dimer, and methylation-protection experiments identify the recognition motif as: c/a GC N9 c/a GC/g.

Investigation into an engraftment defect induced by culturing primitive hematopoietic cells with cytokines.

BACKGROUND: Strategies for transplanting primitive hematopoietic progenitor (PHP) cells are under development that require in vitro manipulation of cells for several hours to several days prior to transplantation. This applies to gene-therapy protocols involving transduction with adenoviral or lentiviral vectors (typically 1 day of ex vivo culture) or retroviral vectors (up to 3 days of culture). METHODS: Human mobilized peripheral blood (MPB) CD34(+) cells were cultured with the cytokines thrombopoietin mimetic peptide (mTPO), flt3 ligand (FL), and c-kit ligand (KL). Equal numbers of CD34(+) cells, either uncultured or cultured for various time periods up to 5 days, were tested for engraftment in sublethally irradiated 8-10 week-old NOD/SCID mice. Cells were also compared for expression and function of several key surface molecules. RESULTS: At a limiting dose of 1 million cells, mice receiving uncultured cells had a mean of 20% CD45(+) (human) cells in their BM 6 weeks post-transplantation, versus 3% for mice receiving 3-5 day cultured cells. Analysis of 10 surface molecules, CD11a, CD18, CD29, CD49d, CD49e, CXCR-4, CD62L, CD31, CD43, and CD44 over a 5-day culture period showed that their expression levels were either maintained or up-regulated on CD34(+) cells and the primitive Thy-1(+) subset. Similar percentages of uncultured and 3-day cultured MPB CD34(+) cells bound to plates coated with vascular cell adhesion molecule-1 (VCAM-1) under both static and physiological flow conditions, and chemotaxis of cultured cells towards stromal-derived factor-1 (SDF-1) was not impaired, suggesting that VLA-4 and CXCR-4 were functional on cultured cells. CD34(+) Thy-1(+) MPB cells cultured with cytokines expressed increasing levels of Fas receptor beginning at 20 h in culture, with peak expression levels after 3 days (mean Day 0 expression, 39%; mean Day 3 expression, 86%), without increased apoptosis. Including inhibitors of caspases in the media of cells cultured for 24-48 h significantly improved their engraftment in a SCID-hu bone-engraftment model. DISCUSSION: Increased susceptibility to apoptosis upon in vivo injection may contribute to impaired engraftment of in vitro manipulated cells. Inhibitors of apoptosis may increase their engrafting capacity in clinical settings.

Expression and localization of IL-1beta mRNA is interrelated with cytoskeletal rearrangement in monocytes stimulated by adherence: a light microscopy in situ hybridization study.

Differences in IL-1beta mRNA expression, stability and translation between non-adherent monocytes and those stimulated by adherence suggest that cytokine regulation is coupled to the function and assembly of cytoskeletal structures. In situ hybridization studies were performed to visualize expression and positioning of IL-1beta mRNA in adherently cultivated monocytes. IL-1beta mRNA expression was heterogeneous with high transcript levels found in spread or polarized cells. Transcripts were compartmentalized to the perinuclear region in spread cells, and partially redistributed with polarization. In contrast to mRNA distribution in other motile cell populations, IL-1beta mRNA did not localize to the distal or proximal actin cytoskeleton. Perinuclear confinement of transcripts required intact actin microfilaments. Treatment with cytoskeleton disruption and detergent extraction suggested that most non-translated IL-1beta mRNA was associated with intermediate filaments. In monocytes stimulated by LPS, IL-1beta, but not IL-1Ra transcripts were redistributed and partially associated, yet not bound to actin microfilaments. The present study demonstrates that IL-1beta mRNA expression and localization in adherent monocytes is interrelated with the cytoskeletal rearrangement upon adherence, spreading and polarization.