Dexamethasone stimulates expression of C-type Natriuretic Peptide in chondrocytes

BACKGROUND: Growth of endochondral bones is regulated through the activity of cartilaginous growth plates. Disruption of the physiological patterns of chondrocyte proliferation and differentiation – such as in endocrine disorders or in many different genetic diseases (e.g. chondrodysplasias) – generally results in dwarfism and skeletal defects. For example, glucocorticoid administration in children inhibits endochondral bone growth, but the molecular targets of these hormones in chondrocytes remain largely unknown. In contrast, recent studies have shown that C-type Natriuretic Peptide (CNP) is an important anabolic regulator of cartilage growth, and loss-of-function mutations in the human CNP receptor gene cause dwarfism. We asked whether glucocorticoids could exert their activities by interfering with the expression of CNP or its downstream signaling components. METHODS: Primary mouse chondrocytes in monolayer where incubated with the synthetic glucocorticoid Dexamethasone (DEX) for 12 to 72 hours. Cell numbers were determined by counting, and real-time PCR was performed to examine regulation of genes in the CNP signaling pathway by DEX. RESULTS: We show that DEX does influence expression of key genes in the CNP pathway. Most importantly, DEX significantly increases RNA expression of the gene encoding CNP itself (Nppc). In addition, DEX stimulates expression of Prkg2 (encoding cGMP-dependent protein kinase II) and Npr3 (natriuretic peptide decoy receptor) genes. Conversely, DEX was found to down-regulate the expression of the gene encoding its receptor, Nr3c1 (glucocorticoid receptor), as well as the Npr2 gene (encoding the CNP receptor). CONCLUSION: Our data suggest that the growth-suppressive activities of DEX are not due to blockade of CNP signaling. This study reveals a novel, unanticipated relationship between glucocorticoid and CNP signaling and provides the first evidence that CNP expression in chondrocytes is regulated by endocrine factors

Analysis of a viral metagenomic library from 200 m depth in Monterey Bay, California constructed by direct shotgun cloning

<p>Abstract</p> <p>Background</p> <p>Viruses have a profound influence on both the ecology and evolution of marine plankton, but the genetic diversity of viral assemblages, particularly those in deeper ocean waters, remains poorly described. Here we report on the construction and analysis of a viral metagenome prepared from below the euphotic zone in a temperate, eutrophic bay of coastal California.</p> <p>Methods</p> <p>We purified viruses from approximately one cubic meter of seawater collected from 200m depth in Monterey Bay, CA. DNA was extracted from the virus fraction, sheared, and cloned with no prior amplification into a plasmid vector and propagated in <it>E. coli </it>to produce the MBv200m library. Random clones were sequenced by the Sanger method. Sequences were assembled then compared to sequences in GenBank and to other viral metagenomic libraries using BLAST analyses.</p> <p>Results</p> <p>Only 26% of the 881 sequences remaining after assembly had significant (E ≤ 0.001) BLAST hits to sequences in the GenBank nr database, with most being matches to bacteria (15%) and viruses (8%). When BLAST analysis included environmental sequences, 74% of sequences in the MBv200m library had a significant match. Most of these hits (70%) were to microbial metagenome sequences and only 0.7% were to sequences from viral metagenomes. Of the 121 sequences with a significant hit to a known virus, 94% matched bacteriophages (Families <it>Podo</it>-, <it>Sipho</it>-, and <it>Myoviridae</it>) and 6% matched viruses of eukaryotes in the Family <it>Phycodnaviridae </it>(5 sequences) or the Mimivirus (2 sequences). The largest percentages of hits to viral genes of known function were to those involved in DNA modification (25%) or structural genes (17%). Based on reciprocal BLAST analyses, the MBv200m library appeared to be most similar to viral metagenomes from two other bays and least similar to a viral metagenome from the Arctic Ocean.</p> <p>Conclusions</p> <p>Direct cloning of DNA from diverse marine viruses was feasible and resulted in a distribution of virus types and functional genes at depth that differed in detail, but were broadly similar to those found in surface marine waters. Targeted viral analyses are useful for identifying those components of the greater marine metagenome that circulate in the subcellular size fraction.</p

Illness cognitions in head and neck squamous cell carcinoma: predicting quality of life outcome

Goals of work: This paper presents an observational study of the longitudinal effects of cancer treatment on quality of life (QoL) in patients treated for head and neck squamous cell carcinoma (HNSCC), and evaluated the contribution of patients' baseline illness cognitions to the prediction of QoL 2 years after diagnosis. Patients and methods: One hundred seventy-seven patients eligible for primary treatment for HNSCC completed the Illness Perception Questionnaire-Revised at baseline and the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire-30 at baseline, at 1-year and 2-year follow-ups. Main results Compared to baseline, patients reported better emotional functioning at both follow-ups (p<0.001), worse social functioning at 12 months (p<0.05), and better global health

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Comprehensive molecular characterization of the hippo signaling pathway in cancer

Hippo signaling has been recognized as a key tumor suppressor pathway. Here, we perform a comprehensive molecular characterization of 19 Hippo core genes in 9,125 tumor samples across 33 cancer types using multidimensional “omic” data from The Cancer Genome Atlas. We identify somatic drivers among Hippo genes and the related microRNA (miRNA) regulators, and using functional genomic approaches, we experimentally characterize YAP and TAZ mutation effects and miR-590 and miR-200a regulation for TAZ. Hippo pathway activity is best characterized by a YAP/TAZ transcriptional target signature of 22 genes, which shows robust prognostic power across cancer types. Our elastic-net integrated modeling further reveals cancer-type-specific pathway regulators and associated cancer drivers. Our results highlight the importance of Hippo signaling in squamous cell cancers, characterized by frequent amplification of YAP/TAZ, high expression heterogeneity, and significant prognostic patterns. This study represents a systems-biology approach to characterizing key cancer signaling pathways in the post-genomic era

Coronary artery calcium scoring in cardiovascular risk assessment of people with family histories of early onset coronary artery disease

Objectives: To assess the predictive value of the Australian absolute cardiovascular disease risk (ACVDR) calculator and other assessment tools for identifying Australians with family histories of early onset coronary artery disease (CAD) who have coronary artery calcification. Design, setting, participants: People without known CAD were recruited at seven Australian hospitals, October 2016 - January 2019. Participants were aged 40-70 years, had a family history of early onset CAD, and a 5-year ACVDR of 2-15%. Main outcome measures: CT coronary artery calcium score greater than zero (any coronary calcification) or greater than 100 (calcification warranting lipid therapy). Results: 1059 participants were recruited; 477 (45%) had non-zero coronary artery calcium scores (median 5-year ACVDR, 4.8% [IQR, 2.9-7.6%]; median coronary artery calcium score, 41.7 [IQR, 8-124]); 582 (55%) did not (median 5-year ACVDR, 3.2% [IQR, 2.0-4.6%]). Of 151 participants with calcium scores of 100 or more, 116 (77%) were deemed to be at low cardiovascular risk by Australian guidelines, while 14 of 75 participants at intermediate risk (19%) had zero calcium scores. The sensitivity of the ACVDR calculator for identifying people with non-zero calcium scores (area under receiver operator curve [AUC], 0.674) was lower than that of the pooled cohort equation (AUC, 0.711; P Conclusions: Coronary artery calcium scoring should be considered as part of the heart health check for patients at intermediate ACVDR risk and with family histories of early onset CAD. Alternative risk calculators may better select such patients for further diagnostic testing and primary prevention therapy

Rationale and design of a trial to personalize risk assessment in familial coronary artery disease

Background: The lifetime risk of coronary artery disease (CAD) is doubled in people with a family history of prematuredisease, yet this risk is not captured in most 5- or 10-year risk assessment algorithms. Coronary artery calcium scoring (CCS) isa marker of subclinical CAD risk, which has been shown in observational studies to provide prognostic information that isincremental to clinical assessment; is relatively inexpensive; and is performed with a small radiation dose. However, the use ofCCS in guiding prevention is not strongly supported by guidelines. Showing definitive evidence of the efficacy and costeffectivenessof CCS is therefore of importance.Study design: The proposed randomized controlled trial of the use of CCS will be targeted to 40- to 70-year-old firstdegreerelatives of patients with CAD onset b60 years old or second-degree relatives of patients with onset b50 years old.Control patients will undergo standard risk scoring and be blinded to CCS results. In the intervention group, primary preventionin patients undergoing CCS will be informed by this score. At 3 years, effectiveness will be assessed on change in plaquevolume at computed tomography coronary angiography, the extent of which has been strongly linked to outcome.Summary: The CAUGHT-CAD trial will provide evidence to inform the guidelines regarding the place of CCS in decisionmaking regarding primary prevention of patients with a family history of premature disease