Chronic kidney disease (CKD) is a worldwide public health threat that increases risk of death due to cardiovascular complications, including left ventricular hypertrophy (LVH). Novel therapeutic ...targets are needed to design treatments to alleviate the cardiovascular burden of CKD. Previously, we demonstrated that circulating concentrations of fibroblast growth factor (FGF) 23 rise progressively in CKD and induce LVH through an unknown FGF receptor (FGFR)-dependent mechanism. Here, we report that FGF23 exclusively activates FGFR4 on cardiac myocytes to stimulate phospholipase Cγ/calcineurin/nuclear factor of activated T cell signaling. A specific FGFR4-blocking antibody inhibits FGF23-induced hypertrophy of isolated cardiac myocytes and attenuates LVH in rats with CKD. Mice lacking FGFR4 do not develop LVH in response to elevated FGF23, whereas knockin mice carrying an FGFR4 gain-of-function mutation spontaneously develop LVH. Thus, FGF23 promotes LVH by activating FGFR4, thereby establishing FGFR4 as a pharmacological target for reducing cardiovascular risk in CKD.
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•In the absence of α-klotho, FGF23 induces binding of FGFR4 to PLCγ•FGF23 activates calcineurin/NFAT signaling in cardiac myocytes via FGFR4•FGFR4 blockade protects CKD rats with high serum FGF23 from cardiac hypertrophy•Knockin mice carrying a FGFR4 gain-of-function mutation develop cardiac hypertrophy
Grabner et al. reveal that FGFR4 mediates the pro-hypertrophic cardiac effects of FGF23, a phosphate-regulating hormone elevated in patients with chronic kidney disease (CKD). Activation of FGFR4/calcineurin/NFAT signaling is sufficient to induce cardiac hypertrophy in mice, while FGFR4 blockade attenuates cardiac hypertrophy in a rat model of CKD.
Imaging-based measures of atherosclerosis such as coronary artery calcium score (CACS) and coronary flow reserve (CFR) as well as carotid atherosclerotic plaque burden (cPB) are predictors of ...cardiovascular events in the general population. The objective of this study was to correlate CACS, cPB, myocardial blood flow (MBF), and CFR in patients with end-stage renal disease (ESRD).
39 patients (mean age 53 ± 12 years) with ESRD prior to kidney transplantation were enrolled. MBF and CFR were quantified at baseline and under hyperemia by 13N-NH3-PET/CT. CACS was calculated from low-dose CT scans acquired for PET attenuation correction. cPB was assessed by 3D ultrasound. Uni- and multivariate regression analyses between these and clinical parameters were performed. Median follow-up time for clinical events was 4.4 years. Kaplan–Meier survival estimates with log-rank test were performed with regards to cardiovascular (CV) events and death of any cause. CACS and cPB were associated in ESRD patients (r = 0.48; p ≤ 0.01). While cPB correlated with age (r = 0.43; p < 0.01), CACS did not. MBFstress was negatively associated with age (r = 0.44; p < 0.01) and time on dialysis (r = 0.42; p < 0.01). There were negative correlations between MBFstress and CACS (r = − 0.62; p < 0.001) and between MBFstress and cPB (r = − 0.43; p < 0.01). Age and CACS were the strongest predictors for MBFstress. CFR was impaired (< 2.0) in eight patients who also presented with higher cPB and higher CACS compared to those with a CFR > 2.0 (p = 0.06 and p = 0.4). In contrast to MBFstress, there was neither a significant correlation between CFR and CACS (r = − 0.2; p = 0.91) nor between CFR and cPB (r = − 0.1; p = 0.55). CV event-free survival was associated with reduced CFR and MBFstress (p = 0.001 and p < 0.001) but not with cPB or CACS.
CACS, cPB, and MBFstress are associated in patients with ESRD. Atherosclerosis is earlier detected by MBFstress than by CFR. CV event-free survival is associated with impaired CFR and MBFstress.
Although the study of thermoregulation in insects has shown that infected animals tend to prefer higher temperatures than healthy individuals, the immune response and energetic consequences of this ...preference remain unknown. We examined the effect of environmental temperature and the energetic costs associated to the activation of the immune response of Tenebrio molitor larvae following a lipopolysaccharide (LPS) challenge. We measured the effect of temperature on immune parameters including phenoloxidase (PO) activity and antibacterial responses. Further as proximal and distal costs of the immune response we determined the standard metabolic rate (SMR) and the loss of body mass (mb), respectively. Immune response was stronger at 30°C than was at 10 or 20°C. While SMR at 10 and 20°C did not differ between immune treatments, at 30°C SMR of LPS-treated larvae was almost 25–60% higher than SMR of PBS-treated and naïve larvae. In addition, the loss in mb was 1.9 and 4.2 times higher in LPS-treated larvae than in PBS-treated and naïve controls. The immune responses exhibited a positive correlation with temperature and both, SMR and mb change, were sensitive to environmental temperature. These data suggest a significant effect of environmental temperature on the immune response and on the energetic costs of immunity.
Background
The objective of the current study was to compare the safety and efficacy between 2 analgesic regimens for patients with head and neck cancer (HNC) undergoing definitive chemoradiation ...(CRT).
Methods
The current study was a prospective, single‐institution, 2‐arm, randomized pilot study. Patients with American Joint Committee on Cancer seventh edition stage II to stage IV squamous cell carcinoma of the head and neck who were undergoing CRT were randomized to either arm 1, which entailed high‐dose gabapentin (2700 mg daily) with the institutional standard of care (hydrocodone and/or acetaminophen progressing to fentanyl as needed), or arm 2, which comprised low‐dose gabapentin (900 mg daily) with methadone. The primary endpoints were safety and toxicity. Secondary endpoints were pain, opioid requirement, and quality of life (QOL). Differences between the treatment arms at multiple time points were compared using a generalized linear mixed regression model with Sidak correction.
Results
A total of 60 patients (31 in arm 1 and 29 in arm 2) were enrolled from April 2015 to August 2017. There was no difference between the treatment arms with regard to adverse events or serious adverse events. Pain was not found to be different between the treatment arms. More patients in arm 1 did not require an opioid during treatment (42% vs 7%; P = .002). Patients in arm 2 experienced significantly better QOL outcomes across multiple domains, including overall health (P = .05), physical functioning (P = .04), role functioning (P = .01), and social functioning (P = .01).
Conclusions
High‐dose prophylactic gabapentin increased the percentage of patients who required no opioid during treatment. Methadone may improve QOL compared with a regimen of short‐acting opioids and fentanyl. However, pain was found to significantly worsen throughout treatment regardless of treatment arm, necessitating further studies to identify a more optimal regimen.
Mucositis is a significant toxicity in most patients undergoing chemoradiation for head and neck cancer. High‐dose, compared to low‐dose, prophylactic gabapentin increases the percentage of patients who require no opioids for mucositis during chemoradiation for head and neck cancer. Among those who require opioids for mucositis, methadone may improve quality of life compared with a regimen of short‐acting opioids and fentanyl.
In the case of a nuclear power plant accident, repetitive/prolonged radioiodine release may occur. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses ...of non-radioactive iodine may protect the thyroid by inhibiting radioiodine uptake into the gland (iodine blockade). Protection is based on a competition at the active carrier site in the cellular membrane and the Wolff–Chaikoff effect, the latter being, however, only transient (24–48 h). Perchlorate may alternatively provide protection by a carrier competition mechanism only. Perchlorate has, however, a stronger affinity to the carrier than iodide. Based on an established biokinetic–dosimetric model developed to study iodine blockade, and after its extension to describe perchlorate pharmacokinetics and the inhibition of iodine transport through the carrier, we computed the protective efficacies that can be achieved by stable iodine or perchlorate in the case of an acute or prolonged radioiodine exposure. In the case of acute radioiodine exposure, perchlorate is less potent than stable iodine considering its ED
50.
A dose of 100 mg stable iodine has roughly the same protective efficacy as 1000 mg perchlorate. For prolonged exposures, single doses of protective agents, whether stable iodine or perchlorate, offer substantially lower protection than after acute radioiodine exposure, and thus repetitive administrations seem necessary. In case of prolonged exposure, the higher affinity of perchlorate for the carrier in combination with the fading Wolff–Chaikoff effect of iodine confers perchlorate a higher protective efficacy compared to stable iodine. Taking into account the frequency and seriousness of adverse effects, iodine and perchlorate at equieffective dosages seem to be alternatives in case of short-term acute radioiodine exposure, whereas preference should be given to perchlorate in view of its higher protective efficacy in the case of longer lasting radioiodine exposures.
Regnase-1 and Roquin are RNA binding proteins essential for degradation of inflammation-related mRNAs and maintenance of immune homeostasis. However, their mechanistic relationship has yet to be ...clarified. Here, we show that, although Regnase-1 and Roquin regulate an overlapping set of mRNAs via a common stem-loop structure, they function in distinct subcellular locations: ribosome/endoplasmic reticulum and processing-body/stress granules, respectively. Moreover, Regnase-1 specifically cleaves and degrades translationally active mRNAs and requires the helicase activity of UPF1, similar to the decay mechanisms of nonsense mRNAs. In contrast, Roquin controls translationally inactive mRNAs, independent of UPF1. Defects in both Regnase-1 and Roquin lead to large increases in their target mRNAs, although Regnase-1 tends to control the early phase of inflammation when mRNAs are more actively translated. Our findings reveal that differential regulation of mRNAs by Regnase-1 and Roquin depends on their translation status and enables elaborate control of inflammation.
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•Regnase-1 and Roquin target overlapping sets of mRNAs with common stem-loop structures•Regnase-1 co-localizes with ribosomes and suppresses translationally active mRNAs•Translation and UPF1 helicase activity are critical for Regnase-1-mediated mRNA decay•Regnase-1 and Roquin control immune-related RNAs in distinct spatiotemporal processes
RNA binding proteins Regnase-1 and Roquin recognize overlapping sets of inflammation-related mRNAs through a conserved stem-loop element but control message stability through distinct mechanisms to modulate the innate immune response.
When electrons populate a flat band their kinetic energy becomes negligible, forcing them to organize in exotic many-body states to minimize their Coulomb energy
. The zeroth Landau level of graphene ...under a magnetic field is a particularly interesting strongly interacting flat band because interelectron interactions are predicted to induce a rich variety of broken-symmetry states with distinct topological and lattice-scale orders
. Evidence for these states stems mostly from indirect transport experiments that suggest that broken-symmetry states are tunable by boosting the Zeeman energy
or by dielectric screening of the Coulomb interaction
. However, confirming the existence of these ground states requires a direct visualization of their lattice-scale orders
. Here we image three distinct broken-symmetry phases in graphene using scanning tunnelling spectroscopy. We explore the phase diagram by tuning the screening of the Coulomb interaction by a low- or high-dielectric-constant environment, and with a magnetic field. In the unscreened case, we find a Kekulé bond order, consistent with observations of an insulating state undergoing a magnetic-field driven Kosterlitz-Thouless transition
. Under dielectric screening, a sublattice-unpolarized ground state
emerges at low magnetic fields, and transits to a charge-density-wave order with partial sublattice polarization at higher magnetic fields. The Kekulé and charge-density-wave orders furthermore coexist with additional, secondary lattice-scale orders that enrich the phase diagram beyond current theory predictions
. This screening-induced tunability of broken-symmetry orders may prove valuable to uncover correlated phases of matter in other quantum materials.
The cation channel transient receptor potential vanilloid (TRPV) 4 is expressed in endothelial and immune cells; however, its role in acute lung injury (ALI) is unclear. The functional relevance of ...TRPV4 was assessed in vivo, in isolated murine lungs, and in isolated neutrophils. Genetic deficiency of TRPV4 attenuated the functional, histological, and inflammatory hallmarks of acid-induced ALI. Similar protection was obtained with prophylactic administration of the TRPV4 inhibitor, GSK2193874; however, therapeutic administration of the TRPV4 inhibitor, HC-067047, after ALI induction had no beneficial effect. In isolated lungs, platelet-activating factor (PAF) increased vascular permeability in lungs perfused with trpv4(+/+) more than with trpv4(-/-) blood, independent of lung genotype, suggesting a contribution of TRPV4 on blood cells to lung vascular barrier failure. In neutrophils, TRPV4 inhibition or deficiency attenuated the PAF-induced increase in intracellular calcium. PAF induced formation of epoxyeicosatrienoic acids by neutrophils, which, in turn, stimulated TRPV4-dependent Ca(2+) signaling, whereas inhibition of epoxyeicosatrienoic acid formation inhibited the Ca(2+) response to PAF. TRPV4 deficiency prevented neutrophil responses to proinflammatory stimuli, including the formation of reactive oxygen species, neutrophil adhesion, and chemotaxis, putatively due to reduced activation of Rac. In chimeric mice, however, the majority of protective effects in acid-induced ALI were attributable to genetic deficiency of TRPV4 in parenchymal tissue, whereas TRPV4 deficiency in circulating blood cells primarily reduced lung myeloperoxidase activity. Our findings identify TRPV4 as novel regulator of neutrophil activation and suggest contributions of both parenchymal and neutrophilic TRPV4 in the pathophysiology of ALI.
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