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Evidence from numerous studies has revealed the synchronous progression of aging in bone and muscle; however, little is known about the underlying mechanisms. To this end, human muscles and bones are harvested and the aging‐associated transcriptional dynamics of two tissues in parallel using single‐cell RNA sequencing are surveyed. A subset of lipid‐associated macrophages (triggering receptor expressed on myeloid cells 2, TREM2+ Macs) is identified in both aged muscle and bone. Genes responsible for muscle dystrophy and bone loss, such as secreted phosphoprotein 1 (SPP1), are also highly expressed in TREM2+ Macs, suggesting its conserved role in aging‐related features. A common transition toward pro‐inflammatory phenotypes in aged CD4+ T cells across tissues is also observed, activated by the nuclear factor kappa B subunit 1 (NFKB1). CD4+ T cells in aged muscle experience Th1‐like differentiation, whereas, in bone, a skewing toward Th17 cells is observed. Furthermore, these results highlight that degenerated myocytes produce BAG6‐containing exosomes that can communicate with Th17 cells in the bone through its receptor natural cytotoxicity triggering receptor 3 (NCR3). This communication upregulates CD6 expression in Th17 cells, which then interact with TREM2+ Macs through CD6‐ALCAM signaling, ultimately stimulating the transcription of SPP1 in TREM2+ Macs. The negative correlation between serum exosomal BCL2‐associated athanogene 6 (BAG6) levels and bone mineral density further supports its role in mediating muscle and bone synchronization with aging. [ABSTRACT FROM AUTHOR]

Abstract Background Owing to the low cost of the high throughput Next Generation Sequencing (NGS) technology, more and more species have been and will be sequenced. However, de novo assemblies of large eukaryotic genomes thus produced are composed of a large number of contigs and scaffolds of medium to small size, having no chromosomal assignment. Radiation hybrid (RH) mapping is a powerful tool for building whole genome maps and has been used for several animal species, to help assign sequence scaffolds to chromosomes and determining their order. Results We report here a duck whole genome RH panel obtained by fusing female duck embryonic fibroblasts irradiated at a dose of 6,000 rads, with HPRT-deficient Wg3hCl2 hamster cells. The ninety best hybrids, having an average retention of 23.6% of the duck genome, were selected for the final panel. To allow the genotyping of large numbers of markers, as required for whole genome mapping, without having to cultivate the hybrid clones on a large scale, three different methods involving Whole Genome Amplification (WGA) and/or scaling down PCR volumes by using the Fluidigm BioMarkTM Integrated Fluidic Circuits (IFC) Dynamic ArrayTM for genotyping were tested. RH maps of APL12 and APL22 were built, allowing the detection of intrachromosomal rearrangements when compared to chicken. Finally, the panel proved useful for checking the assembly of sequence scaffolds and for mapping EST located on one of the smallest microchromosomes. Conclusion The Fluidigm BioMarkTM Integrated Fluidic Circuits (IFC) Dynamic ArrayTM genotyping by quantitative PCR provides a rapid and cost-effective method for building RH linkage groups. Although the vast majority of genotyped markers exhibited a picture coherent with their associated scaffolds, a few of them were discordant, pinpointing potential assembly errors. Comparative mapping with chicken chromosomes GGA21 and GGA11 allowed the detection of the first chromosome rearrangements on microchromosomes between duck and chicken. As in chicken, the smallest duck microchromosomes appear missing in the assembly and more EST data will be needed for mapping them. Altogether, this underlines the added value of RH mapping to improve genome assemblies.

Background: Although the widespread use of modern antiretroviral therapy (ART) has reduced the incidence of talaromycosis in people living with HIV, mortality remains as high as 20% in this population, even after appropriate antifungal treatment. Objectives: The objective of our study was to develop a risk assessment system for HIV‐infected patients with comorbid talaromycosis, in order to provide these patients with appropriate, effective and potentially life‐saving interventions at an early stage of their illness. Patients/Methods: This was a multicentre, retrospective cohort study conducted in China. We built a predictive model based on data from 11 hospitals, and a validated model using the data of 1 hospital located in an endemic area. Results: Forward stepwise multivariate statistical calculations indicated that age, aspartate aminotransferase/alanine transaminase ratio and albumin levels, and BUN levels were valid, independent predictors of the risk of death in HIV‐infected patients with talaromycosis. Our developed and validated risk scoring system is effective for the identification of HIV‐infected patients with talaromycosis at high risk of death at hospital admission (p <.001; AUC = 0.860). In our study, our risk prediction model provided functional and robust discrimination in the validation cohort (p <.001; AUC = 0.793). Conclusion: The prognostic scoring system for mortality assessment developed in the present study is an easy‐to‐use clinical tool designed to accurately assist clinicians in identifying high‐risk patients with talaromycosis. [ABSTRACT FROM AUTHOR]

Aims Arrhythmogenic cardiomyopathy (AC) shows large heterogeneity in its clinical, genetic, and pathological presentation. This study aims to provide a comprehensive atlas of end-stage AC and illustrate the relationships among clinical characteristics, genotype, and pathological profiles of patients with this disease. Methods and results We collected 60 explanted AC hearts and performed standard pathology examinations. The clinical characteristics of patients, their genotype and cardiac magnetic resonance imaging findings were assessed along with pathological characteristics. Masson staining of six representative sections of each heart were performed. Digital pathology combined with image segmentation was developed to calculate distribution of myocardium, fibrosis, and adipose tissue. An unsupervised clustering based on fibrofatty distribution containing four subtypes was constructed. Patients in Cluster 1 mainly carried desmosomal mutations (except for desmoplakin) and were subjected to transplantation at early age; this group was consistent with classical 'desmosomal cardiomyopathy'. Cluster 2 mostly had non-desmosomal mutations and showed regional fibrofatty replacement in right ventricle. Patients in Cluster 3 showed parallel progression, and included patients with desmoplakin mutations. Cluster 4 is typical left-dominant AC, although the genetic background of these patients is not yet clear. Multivariate regression analysis revealed precordial QRS voltage as an independent indicator of the residual myocardium of right ventricle, which was validated in predicting death and transplant events in the validation cohort (n  = 92). Conclusion This study provides a novel classification of AC with distinct genetic backgrounds indicating different potential pathogenesis. Cluster 1 is distinct in genotype and clinicopathology and can be defined as 'desmosomal cardiomyopathy'. Precordial QRS amplitude is an independent indicator reflecting the right ventricular remodelling, which may be able to predict transplant/death events for AC patients. View large Download slide View large Download slide [ABSTRACT FROM AUTHOR]