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Background: Anthracycline-induced cardiotoxicity is a well-known serious clinical entity. However, detailed mechanistic insights on how short-term administration leads to late and long-lasting cardiotoxicity, are still largely undiscovered. We hypothesize that chemotherapy provokes a memory effect at the level of epigenomic DNA modifications which subsequently lead to cardiotoxicity even years after cessation of chemotherapy. Methods: We explored the temporal evolution of epigenetic modifiers in early and late cardiotoxicity due to anthracyclines by means of RNA-sequencing of human endomyocardial left ventricular biopsies and mass spectrometry of genomic DNA. Based on these findings, validation of differentially regulated genes was obtained by performing RT-qPCR. Finally, a proof-of-concept in vitro mechanistic study was performed to dissect some of the mechanistic aspects of epigenetic memory in anthracycline-induced cardiotoxicity. Results: Correlation of gene expression between late and early onset cardiotoxicity revealed an R 2 value of 0.98, demonstrating a total of 369 differentially expressed genes (DEGs, FDR < 0.05). of which 72% (n = 266) were upregulated, and 28% of genes, (n = 103) downregulated in later as compared to earlier onset cardiotoxicity. Gene ontology analysis showed significant enrichment of genes involved in methyl-CpG DNA binding, chromatin remodeling and regulation of transcription and positive regulation of apoptosis. Differential mRNA expression of genes involved in DNA methylation metabolism were confirmed by RT-qPCR in endomyocardial biopsies. In a larger biopsy cohort, it was shown that Tet2 was more abundantly expressed in cardiotoxicity biopsies vs. control biopsies and vs. non-ischemic cardiomyopathy patients. Moreover, an in vitro study was performed: following short-term doxorubicin treatment, H9c2 cells were cultured and passaged once they reached a confluency of 70%-80%. When compared to vehicle-only treated cells, in doxorubicin-treated cells, three weeks after short term treatment, Nppa, Nppb, Tet1/2 and other genes involved in active DNA demethylation were markedly upregulated. These alterations coincided with a loss of DNA methylation and a gain in hydroxymethylation, reflecting the epigenetic changes seen in the endomyocardial biopsies. Conclusions: Short-term administration of anthracyclines provokes long-lasting epigenetic modifications in cardiomyocytes both in vivo and in vitro, which explain in part the time lapse between the use of chemotherapy and the development of cardiotoxicity and, eventually, heart failure.
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There are numerous indications for hybrid breast reconstruction, with the most common being patients who have inadequate donor site volume to achieve the desired breast volume. This article reviews all aspects of hybrid breast reconstruction, including preoperative and assessment, operative technique and considerations, and postoperative management.
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Neoplasias da Mama , Mamoplastia , Retalho Perfurante , Humanos , Feminino , Mastectomia/métodos , Mamoplastia/métodos , Estudos RetrospectivosRESUMO
Enriched tumor epithelium, tumor-associated stroma, and whole tissue were collected by laser microdissection from thin sections across spatially separated levels of ten high-grade serous ovarian carcinomas (HGSOCs) and analyzed by mass spectrometry, reverse phase protein arrays, and RNA sequencing. Unsupervised analyses of protein abundance data revealed independent clustering of an enriched stroma and enriched tumor epithelium, with whole tumor tissue clustering driven by overall tumor "purity." Comparing these data to previously defined prognostic HGSOC molecular subtypes revealed protein and transcript expression from tumor epithelium correlated with the differentiated subtype, whereas stromal proteins (and transcripts) correlated with the mesenchymal subtype. Protein and transcript abundance in the tumor epithelium and stroma exhibited decreased correlation in samples collected just hundreds of microns apart. These data reveal substantial tumor microenvironment protein heterogeneity that directly bears on prognostic signatures, biomarker discovery, and cancer pathophysiology and underscore the need to enrich cellular subpopulations for expression profiling.
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Patients with cardiovascular comorbidities are more susceptible to severe infection with SARS-CoV-2, known to directly cause pathological damage to cardiovascular tissue. We outline a screening platform using human embryonic stem cell-derived cardiomyocytes, confirmed to express the protein machinery critical for SARS-CoV-2 infection, and a SARS-CoV-2 spike-pseudotyped virus system. The method has allowed us to identify benztropine and DX600 as novel inhibitors of SARS-CoV-2 infection in a clinically relevant stem cell-derived cardiomyocyte line. Discovery of new medicines will be critical for protecting the heart in patients with SARS-CoV-2, and for individuals where vaccination is contraindicated.
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Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células-Tronco Embrionárias Humanas/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/virologia , SARS-CoV-2/fisiologia , Benzotropina/farmacologia , Humanos , Miócitos Cardíacos/citologia , Peptídeos/farmacologiaRESUMO
OBJECTIVE: This study compared the level of prejudice against obese individuals (obesity bias) among final-year health and non-health students, and associated obesity education. METHODS: Cross-sectional online survey of 479 final-year students (292 health and 187 non-health) from Griffith University, Australia. Implicit and explicit obesity bias was measured using validated tools, and perceived obesity education ranked from "none" to "excellent." Data were analyzed quantitatively using analysis of variance and independent sample t tests. Statistical significance was set at P < .05. RESULTS: Students' mean age was 26.2 ± 7.6 years and body mass index was 23.2 ± 4.7 kg/m(2). Health and non-health students exhibited significant levels of obesity bias. Non-health students were more likely to suggest that obese individuals lacked willpower (P = .03). Students' self-reported obesity education varied considerably. Those who reported a higher level of genetics-related obesity education were less likely to believe that obese individuals were "bad" (P = .002) or to show concern about putting on weight (P = .01). CONCLUSIONS AND IMPLICATIONS: Obesity bias exists in health students in Australia and is similar to non-health students' obesity bias levels. Students' self-reported genetics-related obesity education may be associated with obesity bias. Modifications to existing health curricula should be considered to reduce obesity bias among future health professionals.