Expression and function of conserved nuclear receptor genes in Caenorhabditis elegans

AbstractThe Caenorhabditis elegans genome encodes 284 nuclear receptor (NR) genes. Among these 284 NR genes are 15 genes conserved among the Metazoa. Here, we analyze the expression and function of eight heretofore uncharacterized conserved C. elegans NR genes. Reporter gene analysis demonstrates that these genes have distinct expression patterns and that a majority of the C. elegans cell types express a conserved NR gene. RNA interference with NR gene function resulted in visible phenotypes for three of the genes, revealing functions in various processes during postembryonic development. Five of the conserved NR genes are orthologs of NR genes that function during molting and metamorphosis in insects. Functional studies confirm a role for most of these ‘ecdysone cascade’ NR orthologs during the continuous growth and dauer molts. Transcript levels for these genes fluctuate in a reiterated pattern during the molting cycles, reminiscent of the expression hierarchy observed in the insect ecdysone response. Together, these analyses provide a foundation for further dissecting the role of NRs in nematode development as well as for evaluating conservation of NR functions among the Metazoa

Towards improving peer review: Crowd-sourced insights from Twitter

Peer review is an essential part of academic publishing, yet many authors, reviewers, and editors have reportedly encountered problems with the review process. Some scholars view peer-review as a necessary process for the advancement of science, while other scholars argue that for many publishers and journals, both authors and reviewers are being exploited. The aim of this commentary is two-fold. First, to provide a narrative review of current perspectives and available research on the peer-review process to date, and second, to summarise potential solutions elicited from scholars on Twitter. A review of the literature identified several problems with peer-review including publication delays, an over reliance on a narrow pool of reviewers, threats to anonymity, perceived exploitation, as well as overworked editors. Recommendations to redress these issues that emerged from scholars on Twitter suggested publishers, journals, their editors and associate editors, universities, individual academics and their communities all have a role to play towards creating an equitable and fair system. This commentary aims to ignite conversations about improving the peer-review process

Mechanics of lipid bilayer junctions affecting the size of a connecting lipid nanotube

In this study we report a physical analysis of the membrane mechanics affecting the size of the highly curved region of a lipid nanotube (LNT) that is either connected between a lipid bilayer vesicle and the tip of a glass microinjection pipette (tube-only) or between a lipid bilayer vesicle and a vesicle that is attached to the tip of a glass microinjection pipette (two-vesicle). For the tube-only configuration (TOC), a micropipette is used to pull a LNT into the interior of a surface-immobilized vesicle, where the length of the tube L is determined by the distance of the micropipette to the vesicle wall. For the two-vesicle configuration (TVC), a small vesicle is inflated at the tip of the micropipette tip and the length of the tube L is in this case determined by the distance between the two interconnected vesicles. An electrochemical method monitoring diffusion of electroactive molecules through the nanotube has been used to determine the radius of the nanotube R as a function of nanotube length L for the two configurations. The data show that the LNT connected in the TVC constricts to a smaller radius in comparison to the tube-only mode and that tube radius shrinks at shorter tube lengths. To explain these electrochemical data, we developed a theoretical model taking into account the free energy of the membrane regions of the vesicles, the LNT and the high curvature junctions. In particular, this model allows us to estimate the surface tension coefficients from R(L) measurements

Increased duration of co-contraction of medial knee muscles is associated with greater progression of knee osteoarthritis

Background: As knee osteoarthritis (OA) cannot be cured, treatments that slow structural disease progression are a priority. Knee muscle activation has a potential role in OA pathogenesis. Although enhanced knee muscle co-contraction augments joint stability; this may speed structural disease progression by increased joint load. Objective: This study investigated the relationship between cartilage loss and duration of co-contraction of medial/lateral knee muscles in medial knee OA. Design: Prospective cohort study. Methods: Medial (vastus medialis; semimembranosus) and lateral (vastus lateralis; biceps femoris) knee muscle myoelectric activity was recorded in 50 people with medial knee OA during natural speed walking at baseline. Medial tibial cartilage volume was measured from MRI at baseline and 12 months. Relationships between percent volume loss and duration of co-contraction of medial/lateral muscles around stance phase and ratio of duration of medial to lateral muscle co-contraction were evaluated with multiple linear regression. Results: Greater duration of medial muscle co-contraction and greater duration of medial relative to lateral co-contraction correlated positively with annual percent loss of medial tibial cartilage volume (. P = 0.003). Estimated cartilage loss was 0.14 (95% confidence interval -0.23 to -0.05) greater for each increase in medial muscle co-contraction duration of 1% of the gait cycle. Lateral muscle co-contraction inversely correlated with cartilage loss. Conclusion: Data support the hypothesis that augmented medial knee muscle co-contraction underpins faster progression of medial knee OA. Increased duration of lateral muscle co-contraction protected against medial cartilage loss. Exercise and biomechanical interventions to change knee muscle activation patterns provide possible candidates to slow progression of knee OA

Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts

Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1α protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1α (HIF-1α) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1α may be a novel therapeutic target to modulate the scar fibrosis process

Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts

Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1α protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1α (HIF-1α) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1α may be a novel therapeutic target to modulate the scar fibrosis process

Advanced Colloids Experiment (Microscopy) - ACE-M2R

Increment 53 - 54 Science Symposium presentation of Advanced Colloids Experiment (ACE-H-2) to RPO. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators

Mindfulness Training Supports Quality of Life and Advance Care Planning in Adults With Metastatic Cancer and Their Caregivers: Results of a Pilot Study

Background: Emotional distress often causes patients with cancer and their family caregivers (FCGs) to avoid end-of-life discussions and advance care planning (ACP), which may undermine quality of life (QoL). Most ACP interventions fail to address emotional barriers that impede timely ACP. Aim: We assessed feasibility, acceptability, and preliminary effects of a mindfulness-based intervention to facilitate ACP for adults with advanced-stage cancer and their FCGs. Design: A single-arm pilot was conducted to assess the impact of a 6-week group mindfulness intervention on ACP behaviors (patients only), QoL, family communication, avoidant coping, distress, and other outcomes from baseline (T1) to post-intervention (T2) and 1 month later (T3). Participants: Eligible patients had advanced-stage solid malignancies, limited ACP engagement, and an FCG willing to participate. Thirteen dyads (N = 26 participants) enrolled at an academic cancer center in the United States. Results: Of eligible patients, 59.1% enrolled. Attendance (70.8% across 6 sessions) and retention (84.6% for patients; 92.3% for FCGs) through T3 were acceptable. Over 90% of completers reported high intervention satisfaction. From T1 to T3, patient engagement more than doubled in each of 3 ACP behaviors assessed. Patients reported large significant decreases in distress at T2 and T3. Family caregivers reported large significant improvements in QoL and family communication at T2 and T3. Both patients and FCGs reported notable reductions in sleep disturbance and avoidant coping at T3. Conclusions: The mindfulness intervention was feasible and acceptable and supported improvements in ACP and associated outcomes for patients and FCGs. A randomized trial of mindfulness training for ACP is warranted

The Consensus Hepatitis C Cascade of Care:standardized reporting to monitor progress toward elimination

Cascade-of-care (CoC) monitoring is an important component of the response to the global hepatitis C virus (HCV) epidemic. CoC metrics can be used to communicate, in simple terms, the extent to which national and subnational governments are advancing on key targets, and CoC findings can inform strategic decision-making regarding how to maximize the progression of individuals with HCV to diagnosis, treatment, and cure. The value of reporting would be enhanced if a standardized approach were used for generating CoCs. We have described the Consensus HCV CoC that we developed to address this need and have presented findings from Denmark, Norway, and Sweden, where it was piloted. We encourage the uptake of the Consensus HCV CoC as a global instrument for facilitating clear and consistent reporting via the World Health Organization (WHO) viral hepatitis monitoring platform and for ensuring accurate monitoring of progress toward WHO's 2030 hepatitis C elimination targets.</p