Transcriptomic dysregulation and autistic-like behaviors in Kmt2c haploinsufficient mice rescued by an LSD1 inhibitor

Recent studies have consistently demonstrated that the regulation of chromatin and gene transcription plays a pivotal role in the pathogenesis of neurodevelopmental disorders. Among many genes involved in these pathways, KMT2C, encoding one of the six known histone H3 lysine 4 (H3K4) methyltransferases in humans and rodents, was identified as a gene whose heterozygous loss-of-function variants are causally associated with autism spectrum disorder (ASD) and the Kleefstra syndrome phenotypic spectrum. However, little is known about how KMT2C haploinsufficiency causes neurodevelopmental deficits and how these conditions can be treated. To address this, we developed and analyzed genetically engineered mice with a heterozygous frameshift mutation of Kmt2c (Kmt2c+/fs mice) as a disease model with high etiological validity. In a series of behavioral analyses, the mutant mice exhibit autistic-like behaviors such as impairments in sociality, flexibility, and working memory, demonstrating their face validity as an ASD model. To investigate the molecular basis of the observed abnormalities, we performed a transcriptomic analysis of their bulk adult brains and found that ASD risk genes were specifically enriched in the upregulated differentially expressed genes (DEGs), whereas KMT2C peaks detected by ChIP-seq were significantly co-localized with the downregulated genes, suggesting an important role of putative indirect effects of Kmt2c haploinsufficiency. We further performed single-cell RNA sequencing of newborn mouse brains to obtain cell type-resolved insights at an earlier stage. By integrating findings from ASD exome sequencing, genome-wide association, and postmortem brain studies to characterize DEGs in each cell cluster, we found strong ASD-associated transcriptomic changes in radial glia and immature neurons with no obvious bias toward upregulated or downregulated DEGs. On the other hand, there was no significant gross change in the cellular composition. Lastly, we explored potential therapeutic agents and demonstrate that vafidemstat, a lysine-specific histone demethylase 1 (LSD1) inhibitor that was effective in other models of neuropsychiatric/neurodevelopmental disorders, ameliorates impairments in sociality but not working memory in adult Kmt2c+/fs mice. Intriguingly, the administration of vafidemstat was shown to alter the vast majority of DEGs in the direction to normalize the transcriptomic abnormalities in the mutant mice (94.3 and 82.5% of the significant upregulated and downregulated DEGs, respectively, P < 2.2 × 10-16, binomial test), which could be the molecular mechanism underlying the behavioral rescuing. In summary, our study expands the repertoire of ASD models with high etiological and face validity, elucidates the cell-type resolved molecular alterations due to Kmt2c haploinsufficiency, and demonstrates the efficacy of an LSD1 inhibitor that might be generalizable to multiple categories of psychiatric disorders along with a better understanding of its presumed mechanisms of action.

Topologically associating domains define the impact of de novo promoter variants on autism spectrum disorder risk

Whole-genome sequencing (WGS) studies of autism spectrum disorder (ASD) have demonstrated the roles of rare promoter de novo variants (DNVs). However, most promoter DNVs in ASD are not located immediately upstream of known ASD genes. In this study analyzing WGS data of 5,044 ASD probands, 4,095 unaffected siblings, and their parents, we show that promoter DNVs within topologically associating domains (TADs) containing ASD genes are significantly and specifically associated with ASD. An analysis considering TADs as functional units identified specific TADs enriched for promoter DNVs in ASD and indicated that common variants in these regions also confer ASD heritability. Experimental validation using human induced pluripotent stem cells (iPSCs) showed that likely deleterious promoter DNVs in ASD can influence multiple genes within the same TAD, resulting in overall dysregulation of ASD-associated genes. These results highlight the importance of TADs and gene-regulatory mechanisms in better understanding the genetic architecture of ASD.

An extremely energetic cosmic ray observed by a surface detector array

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Impact of transcatheter aortic valve implantation on coronary flow reserve by transthoracic Doppler echocardiography 1-year after the intervention in severe aortic stenosis patients

Background

Coronary flow reserve (CFR) which is one of indexes reflecting coronary microcirculation in patients without significant epicardial coronary lesions can be impaired in patients with severe aortic stenosis (AS). It has been shown that CFR is an independent predictor for future cardiovascular events in AS patients. Transcatheter aortic valve implantation (TAVI) has rapidly become widespread and is becoming the standard treatment for severe AS. This procedure may have a good effect on CFR due to reduction of severe afterload in patients with severe AS. Although the recent reports evaluated change in CFR immediately and 6 months after TAVI, it has not been evaluated whether impaired CFR improves 1-year after TAVI in AS patients with preserved left ventricular ejection fraction (LVEF).

Purpose

The purpose of the present study was to investigate whether impaired CFR improves 1-year after TAVI in severe AS patients with preserved LVEF.

Methods

The study population consists of consecutive 105 patients with severe AS undergoing TAVI. Exclusion criteria were atrial fibrillation, old myocardial infarction, history of coronary artery bypass grafting, significant lesions in the left anterior descending artery (LAD), moderate or severe mitral valve disease, history of valve replacement, LVEF &lt;50% and preoperative CFR &gt;2.2. CFR was obtained from coronary flow velocity by transthoracic echocardiography at rest and maximal hyperemia in LAD before, immediately and 1-year after TAVI. We compared CFR between before and after TAVI in the study patients who did not meet the exclusion criteria.

Results

After exclusion of 76 patients who met the exclusion criteria, the final study patients consist of 29 patients (8 male, 84.9±5.2 years). There was no significant difference in LVEF (61.3±3.4% vs 61.6±4.4%, P=0.667) and LV end-diastolic volume (LVEDVI; 58.2±9.2 mL/m2 vs 55.8±9.0 mL/m2, P=0.089) between before and immediately after TAVI. LVEF (61.0±2.8%, P=0.721) and LVEDVI (58.0±9.1 mL/m2, P=0.949) 1-year after TAVI were similar to those before TAVI. There was no significant difference in coronary flow velocity at rest between before and immediately after TAVI (27.4±8.9 vs 24.4±7.0 cm/s, P=0.051) and between before and 1-year after TAVI (25.9±8.3 cm/s, P=0.396). Coronary flow velocity at maximal hyperemia 1-year after TAVI significantly increased compared with that before TAVI (from 48.8±13.9 to 67.9±21.0 cm/s, P&lt;0.001) while there was no significant difference between before and immediately after TAVI (52.0±12.0 cm/s, P=0.186). Impaired CFR before TAVI (1.82±0.28) increased immediately (2.03±0.39, P=0.009) and 1-year after TAVI (2.69±0.57, P&lt;0.001).

Conclusions

The present results suggest that impaired CFR in patients with preserved LVEF improves 1-year after TAVI. TAVI may have a good effect on CFR in severe AS patients with preserved LVEF.

Funding Acknowledgement

Type of funding sources: None.

Development of an application tool to support returnees in Fukushima

To promote radiation protection and health promotion among returning residents (returnees) in coastal areas of Fukushima, eHealth principles were used to develop a new application tool (app) that can record radiation exposure and health status while providing comprehensive support to returnees. Intended users are returnees and health and welfare workers. After assessing their needs, a flowchart and prototype for operational logic were created using commercially available software tools. Professional developers will focus on improving the user interface and ensuring data security. The finished app will be compatible with mobile telephones and tablets. Utility and ease of use are paramount to serve returnees of all ages effectively.

P2700Impact of instantaneous wave-free ratio on graft failure after coronary artery bypass graft surgery

Background

It has been reported that preoperative fractional flow reserve (FFR) is associated with graft patency after coronary artery bypass graft (CABG) and the patency is excellent when a bypass graft is anastomosed on a vessel with positive FFR. However, the association with graft patency has not yet been investigated in its novel counterpart, instantaneous wave-free ratio (iFR), and iFR sometimes contradicts FFR results.

Purpose

The purpose of this study is to assess an impact of preoperative iFR on a graft failure after CABG in patients with coronary arteries showing positive FFR (≤0.80).

Methods

We retrospectively identified patients who had undergone preoperative coronary angiography in conjunction with resting and hyperemic intra-coronary pressure measurements, CABG, and graft evaluation by coronary computed tomography angiography. After excluding vessels with negative FFR (>0.80), vessels were divided into two groups: negative iFR group (iFR >0.89) and positive iFR group (iFR ≤0.89). The rate of graft failure within 1 year after CABG was compared between the two groups.

Results

We analyzed 131 vessels in 89 patients (35 vessels in the negative iFR group and 96 vessels in the positive iFR group). The negative iFR group showed significantly higher iFR (0.92±0.02 vs. 0.74±0.13, P<0.0001) and FFR (0.72±0.06 vs. 0.63±0.09, P<0.0001) than the positive iFR group, although percent diameter stenosis (%DS) was comparable (57±10 vs. 56±9, P=0.47). The graft failure significantly often occurred in the negative iFR group than in the positive iFR group (28.6% vs. 8.3%, P=0.0029). In order to reduce the imbalance in the baseline characteristics except for iFR, 70 vessels were selected by using propensity score matching (n=35 in each group). The propensity score matched vessels also demonstrated significantly higher rate of graft failure in the negative iFR group than in the positive iFR group (28.6% vs. 5.7%, p=0.026) despite much more balanced FFR (0.72±0.06 vs. 0.69±0.07, p=0.02) and %DS (57±10 vs. 57±9, p=1.000).

Conclusions

Even when FFR is positive, the graft failure is likely to occur when a bypass graft is anastomosed on a vessel with negative iFR compared to a vessel with positive iFR.

Acknowledgement/Funding

None

Detection of a High-Turnover Serotonin Circuit in the Mouse Brain Using Mass Spectrometry Imaging

Monoamine neurotransmitters are released by specialized neurons regulating behavioral, motor, and cognitive functions. Although the localization of monoaminergic neurons in the brain is well known, the distribution and kinetics of monoamines remain unclear. Here, we generated a murine brain atlas of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) levels using mass spectrometry imaging (MSI). We found several nuclei rich in both 5-HT and a catecholamine (DA or NE) and identified the paraventricular nucleus of the thalamus (PVT), where 5-HT and NE are co-localized. The analysis of 5-HT fluctuations in response to acute tryptophan depletion and infusion of isotope-labeled tryptophan in vivo revealed a close kinetic association between the raphe nuclei, PVT, and amygdala but not the other nuclei. Our findings imply the existence of a highly dynamic 5-HT-mediated raphe to PVT pathway that likely plays a role in the brain monoamine system.

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A murine brain atlas of monoamine (5-HT, DA, NE) levels was generated via MS imaging

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We identified several nuclei rich in both 5-HT and a catecholamine (DA or NE)

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The paraventricular nucleus of the thalamus (PVT) had high levels of 5-HT and NE

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The level of 5-HT in raphe to PVT pathway changed dynamically in response to blood Trp level

Mechanical allodynia induced by optogenetic sensory nerve excitation activates dopamine signaling and metabolism in medial nucleus accumbens

The mesolimbic dopaminergic signaling, such as that originating from the ventral tegmental area (VTA) neurons in the medial part of the nucleus accumbens (mNAc), plays a role in complex sensory and affective components of pain. To date, we have demonstrated that optogenetic sensory nerve stimulation rapidly alters the dopamine (DA) content within the mNAc. However, the physiological role and biochemical processes underlying such rapid and regional dynamics of DA remain unclear. In this study, using imaging mass spectrometry (IMS), we observed that sensitized pain stimulation by optogenetic sensory nerve activation increased DA and 3-Methoxytyramine (3-MT; a post-synaptic metabolite obtained following DA degradation) in the mNAc of the experimental mice. To delineate the mechanism associated with elevation of DA and 3-MT, the de novo synthesized DA in the VTA/substantia nigra terminal areas was evaluated using IMS by visualizing the metabolic conversion of stable isotope-labeled tyrosine (¹³C¹⁵N-Tyr) to DA. Our approach revealed that at steady state, the de novo synthesized DA occupied >10% of the non-labeled DA pool in the NAc within 1.5 h of isotope-labeled Tyr administration, despite no significant increase following pain stimulation. These results suggested that sensitized pain triggered an increase in the release and postsynaptic intake of DA in the mNAc, followed by its degradation, and likely delayed de novo DA synthesis. In conclusion, we demonstrated that short, peripheral nerve excitation with mechanical stimulation accelerates the mNAc-specific DA signaling and metabolism which might be associated with the development of mechanical allodynia.

Modified Gant-Miwa-Thiersch procedure (mucosal plication with anal encircling) for rectal prolapse

AIM

Rectal prolapse (RP) is usually associated with elderly women and is well recognized as having a detrimental effect on quality of life. A number of surgical procedures for RP are available, but morbidity and mortality are substantial. The Gant-Miwa-Thiersch procedure (GMT) has been frequently used for RP in Japan. However, as GMT has a high recurrence rate it is not widely used elsewhere. The aim of this study was to evaluate a modified version of GMT (mGMT) in comparison with other procedures.

METHOD

mGMT was performed under spinal or local anaesthesia in 187 patients with RP. No normal mucosa was left between the tags and lateral wounds were created in the Thiersch procedure. Morbidity, mortality and recurrence rates were recorded.

RESULTS

No serious postoperative complications and no operative deaths occurred after mGMT. Eight per cent of patients suffered from infection of the strings. The overall recurrence rate after mGMT was 7.5% with a median follow-up period of 13.8 years.

CONCLUSION

On the basis of these results, we consider that mGMT has a number of advantages: it is minimally invasive, does not require general anaesthesia, is technically simple to perform and is associated with satisfactory outcomes and low morbidity. mGMT should be considered an option for the treatment of RP in elderly patients.

Recurrent Membranous Nephropathy After Kidney Transplantation Associated With Phospholipase A2 Receptor and Successfully Treated With Rituximab: A Case Report

Primary membranous nephropathy (MN) is an organ-specific autoimmune disease mainly caused by autoantibodies acting against the podocyte antigen M-type phospholipase A2 receptor 1 (PLA2R). Herein we present the clinical and histologic findings, including PLA2R staining, of early recurrent MN after kidney transplantation that was successfully treated with rituximab. A 60-year-old Japanese man had end-stage renal failure due to steroid-resistant primary MN and underwent ABO-incompatible living donor kidney transplantation. At 1 month after transplantation, a protocol biopsy revealed positive granular staining of IgG, C4d, and PLA2R on glomerular capillaries (GCs) without any abnormalities on light microscopy (LM). Although the patient had low-level proteinuria, recurrent MN was suspected based on the positive PLA2R staining; he was treated with an angiotensin receptor blocker and a single dose of 200 mg rituximab. However, proteinuria gradually increased to 877 mg/d. At 21 months after transplantation, a graft biopsy revealed spikes along the outer aspects of GC on LM, with stronger staining for PLA2R than that at 1 month after transplantation. A single dose of 500 mg rituximab was added, which effectively reduced proteinuria, and clinical remission continued until 3 years after transplantation. The latest graft biopsy showed reduced staining of PLA2R. The disease activity and therapeutic effect were well-reflected in the intensity of PLA2R staining. An approach intending an early diagnosis by protocol biopsy using PLA2R immunostaining is made and early treatment with rituximab will help reduce the risk of kidney graft loss due to recurrent primary MN.

Site-specific Chemotherapy Based on Predicted Primary Site by Pathological Profile for Carcinoma of Unknown Primary Site

AIMS

Although platinum-based combination chemotherapies are commonly used for unfavourable subsets of cancer of unknown primary (CUP), the prognosis remains poor. Several studies have suggested that gene expression profiling or immunohistochemistry was useful for the prediction of primary sites in CUP, and site-specific therapy based on predicted primary sites might improve overall outcomes. In Japan, to identify primary sites, immunohistochemical tests were commonly used for CUP in clinical practice. However, it is unclear whether site-specific therapy based on predicted primary sites by pathological examination contributes survival benefit for unfavourable CUP subsets.

PATIENTS AND METHODS

In this study, 122 patients with unfavourable subsets of CUP were retrospectively reviewed. Ninety patients assigned to cohort A after July 2012 had received chemotherapy according to predicted primary sites; 32 patients assigned to cohort B before June 2012 had received platinum-based empiric chemotherapy.

RESULTS

In cohort A, 56 patients (62.2%) with predicted primary sites by pathological examination received site-specific therapy; 34 patients (37.8%) with unpredictable primary sites received platinum-based empiric chemotherapy, the same as cohort B. The median overall survival was 20.3 months in patients with predictable primary sites in cohort A and 10.7 months in those of cohort B, with a significant difference between these cohorts (P = 0.03, adjusted hazard ratio = 0.57, 95% confidence interval 0.34-0.94).

CONCLUSION

Site-specific therapy based on predicted primary sites by pathological examination could improve prognosis in patients with an unfavourable subset of CUP.

Optogenetic astrocyte activation evokes BOLD fMRI response with oxygen consumption without neuronal activity modulation

Functional magnetic resonance imaging (fMRI) based on the blood oxygenation level-dependent (BOLD) signal has been used to infer sites of neuronal activation in the brain. A recent study demonstrated, however, unexpected BOLD signal generation without neuronal excitation, which led us to hypothesize the presence of another cellular source for BOLD signal generation. Collective assessment of optogenetic activation of astrocytes or neurons, fMRI in awake mice, electrophysiological measurements, and histochemical detection of neuronal activation, coherently suggested astrocytes as another cellular source. Unexpectedly, astrocyte-evoked BOLD signal accompanied oxygen consumption without modulation of neuronal activity. Imaging mass spectrometry of brain sections identified synthesis of acetyl-carnitine via oxidative glucose metabolism at the site of astrocyte-, but not neuron-evoked BOLD signal. Our data provide causal evidence that astrocytic activation alone is able to evoke BOLD signal response, which may lead to reconsideration of current interpretation of BOLD signal as a marker of neuronal activation.

Risk of serious adverse events and fatal adverse events with sorafenib in patients with solid cancer: a meta-analysis of phase 3 randomized controlled trials†

Background

Sorafenib is a multikinase-tyrosine kinase inhibitor commonly used in a variety of cancers. There are concerns about the increased risk of serious adverse events (SAEs) and fatal adverse events (FAEs) with sorafenib. We performed an up-to-date meta-analysis of all phase 3 randomized controlled trials (RCTs) of sorafenib to quantify the increased risk of SAEs and FAEs.

Patients and methods

We carried out a systematic search of electronic databases for studies published from inception to February 2016 without any restrictions. Eligibility criteria included phase 3 RCTs of solid tumors comparing sorafenib, alone or in combination with nontargeted chemotherapy (Sorafenib arm) versus placebo or nontargeted chemotherapy (control arm). Data on SAEs and FAEs for both the arms were extracted from each study and pooled to determine the overall incidence, relative risks (RRs) and 95% Confidence Intervals (CIs).

Results

Of 471 studies identified, a total of 12 phase 3 RCTs involving 6797 solid cancer patients comparing sorafenib with control met the eligibility criteria and were included. The overall incidence of SAEs and FAEs with sorafenib were 26.4% (95% CI, 18.0-36.9%) and 1.3% (95% CI: 0.8-2.2%), respectively. Compared with control, sorafenib use significantly increased the risk of both SAEs (RR: 1.49, 95% CI: 1.18-1.89, P = 0.001) and FAEs (RR: 1.82, 95% CI: 1.05-3.14, P = 0.033). This association varied significantly with cancer types (P < 0.001) and approval status (P = 0.012) for SAEs but no evidence of heterogeneity was found for FAEs.

Conclusions

This meta-analysis of phase 3 RCTs demonstrates an increased risk of both SAEs and FAEs with sorafenib use in adult patients with solid cancers. This quantification of increased risks of SAEs and FAEs will be important in considering the trade-off of sorafenib treatment during shared decision-making.

Role of Neuron-Glial Interaction Mediated by IL-1β in Ectopic Tooth Pain

Although many reports have demonstrated that ectopic pain develops in the orofacial region following tooth pulp inflammation, which often causes misdiagnosis and inappropriate treatment for patients with pulpitis, the precise mechanism remains unknown. In the present study, we hypothesized that the functional interaction between satellite glial cells and neurons mediated by interleukin 1β (IL-1β) in the trigeminal ganglion (TG) is involved in ectopic orofacial pain associated with tooth pulp inflammation. The digastric muscle electromyogram (D-EMG) activity elicited by capsaicin administration into the maxillary second molar tooth pulp was analyzed to evaluate the noxious reflex and was significantly increased in rats with inflammation of the maxillary first molar (M1) versus rats injected with saline. A significant increase in the expression of connexin43 (Cx43), a gap junction containing protein, was observed in activated satellite glial cells surrounding second molar-innervating neurons in the TG after M1 pulpitis. Daily administration of Gap26, a Cx43 mimetic peptide and inhibitor, in the TG significantly suppressed the enhancement of capsaicin-induced D-EMG activity and the percentage of Fluoro-Gold (FG)-labeled cells encircled by glial fibrillary acid protein-immunoreactive (IR) + Cx43-IR cells after M1 pulp inflammation ( P < 0.01). The percentage of FG-labeled cells encircled by glial fibrillary acid protein-IR + IL-1β-IR cells, IL-1 type I receptor-IR cells labeled with FG, and TRPV1-IR cells labeled with FG significantly increased after M1 pulp inflammation ( P < 0.01). Daily administration of IL-1ra, an IL-1 receptor antagonist, into the TG significantly reduced the enhancement of capsaicin-induced D-EMG activity and the percentage of TRPV1-IR neurons labeled with FG after M1 pulp inflammation ( P < 0.01). The present findings suggest that satellite glial cell is activated in the TG via activated gap junctions composed of Cx43 following tooth pulp inflammation, which leads to the hyperactivation of remote neurons via IL-1β mechanisms and results in ectopic tooth pulp pain in the adjacent tooth.

Effects of short-term fasting on the Akt-mediated pathway involved in protein metabolism in chicken skeletal muscle

In the present study, we show that short-term (4 h) fasting significantly decreased the levels of protein synthesis-related factors such as the plasma insulin concentration, skeletal muscle pAkt, and pS6 levels in 2-wk-old chickens (P < 0.05). An intravenous injection of insulin significantly elevated the contents of pAkt and p-S6 in the skeletal muscle (P < 0.01). These findings suggest that decreasing the plasma insulin causes the downregulation of the Akt/S6 pathway in chicken skeletal muscle under short-term fasting conditions. However, protein synthesis was not significantly affected by short-term fasting. In addition, no significant change was observed in the levels of proteolysis-related factors such as plasma N^τ-methylhistidine, phosphorylated forkhead box class O, and muscle ring finger-1 during 4-h fasting, indicating that short-term fasting does not induce skeletal muscle proteolysis in chickens. Interestingly, atrogin-1 expression significantly increased after 2-h fasting (P < 0.05), and insulin injection significantly reversed the fasting-induced atrogin-1 expression in chicken skeletal muscle (P < 0.01). Collectively, these findings suggest that short-term fasting downregulates the insulin-stimulated Akt/S6 pathway but does not significantly affect protein synthesis and proteolysis in chicken skeletal muscle, and that atrogin-1 expression is upregulated in a FOXO1-independent manners.

Rewiring of embryonic glucose metabolism via suppression of PFK-1 and aldolase during mouse chorioallantoic branching

Adapting the energy metabolism state to changing bioenergetic demands is essential for mammalian development accompanying massive cell proliferation and cell differentiation. However, it remains unclear how developing embryos meet the changing bioenergetic demands during the chorioallantoic branching (CB) stage, when the maternal-fetal exchange of gases and nutrients is promoted. In this study, using metabolome analysis with mass-labeled glucose, we found that developing embryos redirected glucose carbon flow into the pentose phosphate pathway via suppression of the key glycolytic enzymes PFK-1 and aldolase during CB. Concomitantly, embryos exhibited an increase in lactate pool size and in the fractional contribution of glycolysis to lactate biosynthesis. Imaging mass spectrometry visualized lactate-rich tissues, such as the dorsal or posterior neural tube, somites and head mesenchyme. Furthermore, we found that the heterochronic gene Lin28a could act as a regulator of the metabolic changes observed during CB. Perturbation of glucose metabolism rewiring by suppressing Lin28a downregulation resulted in perinatal lethality. Thus, our work demonstrates that developing embryos rewire glucose metabolism following CB for normal development.

Highlighted article: Metabolic remodelling during E8.5 to E10.5 in mouse redirects glucose carbon into the pentose phosphate pathway, a process partially regulated by Lin28a.

Prognostic significance of gene amplification of ACTN4 in stage I and II oral tongue cancer

Despite complete resection of the early stage of oral tongue cancer by partial glossectomy, late cervical lymph node metastasis is frequently observed. Gene amplification of ACTN4 (protein name: actinin-4) is closely associated with the metastatic potential of various cancers. This retrospective study was performed to demonstrate the potential usefulness of ACTN4 gene amplification as a prognostic biomarker in patients with stage I/II oral tongue cancer. Fifty-four patients with stage I/II oral tongue cancer were enrolled retrospectively, in accordance with the reporting recommendations for tumour marker prognostic studies (REMARK) guidelines. The copy number of ACTN4 and the protein expression of actinin-4 were evaluated by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), respectively. The overall survival time of patients with gene amplification of ACTN4 was significantly shorter than that of patients without gene amplification (P=0.0010, log-rank test). Gene amplification of ACTN4 was a significant independent risk factor for death in patients with stage I/II oral tongue cancer (hazard ratio 6.08, 95% confidence interval 1.66-22.27). Gene amplification of ACTN4 is a potential prognostic biomarker for overall survival in oral tongue cancer.

Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment

A polytetrafluoroethylene (PTFE) surface was modified using atmospheric pressure plasma treatment under heating (heat-assisted plasma treatment) to promote its direct adhesion to isobutylene–isoprene rubber (IIR) without any adhesives.

Correction: Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment

Correction for ‘Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment’ by Y. Ohkubo et al., RSC Adv., 2017, 7, 6432–6438.

Arl8b is required for lysosomal degradation of maternal proteins in the visceral yolk sac endoderm of mouse embryos

The small GTPase Arl8b localizes primarily to lysosomes and is involved in lysosomal motility and fusion. Here, we show that Arl8b is required for lysosomal degradation of maternal proteins in the visceral yolk sac endoderm (VYSE), an apical cell layer of the visceral yolk sac, of mouse embryos. The VYSE actively takes up maternal materials from uterine fluid and degrades them in lysosomes to provide breakdown products to the embryo as energy sources. Arl8b gene-trap mice (Arl8b−/−) displayed decreased early embryo body size. The Arl8b−/− VYSE exhibited defective endocytic trafficking to the lysosome and accumulation of maternal proteins such as albumin and immunoglobulin G in late endocytic organelles. Furthermore, Transthyretin-Cre;Arl8bflox/flox mice in which Arl8b was ablated specifically in the VYSE also showed decreased embryo body size, defects in trafficking to the lysosome, and reduction of the free amino acid level in the embryos. Taken together, these results suggest that Arl8b mediates lysosomal degradation of maternal proteins in the VYSE, thereby contributing to mouse embryonic development.

Cyclic Mechanical Strain Regulates the PTHrP Expression in Cultured Chondrocytes via Activation of the Ca2+ Channel

The association between mechanical stimulation and chondrocyte homeostasis has been reported. However, the participation of PTHrP (parathyroid-hormone-related protein) in the mechano-regulation of chondrocyte metabolism remains unclear. We determined whether mechanical stimulation of chondrocytes induces the expression of PTHrP and, further, whether the mechano-modulation of PTHrP is dependent on the maturational status of chondrocytes. Cyclic mechanical strain was applied to rat growth plate chondrocytes at the proliferating, matrix-forming, and hypertrophic stages at 30 cycles/min. Cyclic mechanical strain significantly increased PTHrP mRNA levels in chondrocytes at the proliferating and matrix-forming stages only. The induction of PTHrP was dependent on loading magnitude at the proliferating stage. Using specific ion channel blockers, we determined that mechano-induction of PTHrP was inhibited by nifedipine, a Ca2+ channel blocker. These results suggest that mechanical induction of PTHrP possibly provides the environment for greater chondrocyte replication and matrix formation that would subsequently affect cartilage formation.