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 <50% and preoperative CFR >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<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<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

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.

Effect of coadministration of rifampicin on the pharmacokinetics of linezolid: clinical and animal studies

Background

Combination therapy of linezolid (LZD) and rifampicin (RFP) may be more effective than monotherapy for treating gram-positive bacterial infections, but several studies have suggested that RFP decreases LZD exposures, thereby increasing the risk of therapeutic failure and emergence of LZD-resistant strains. However, the mechanism of the drug-drug interaction between LZD and RFP is unknown.

Methods

We conducted a prospective, open-label, uncontrolled clinical study in Japanese patients receiving LZD and RFP to evaluate the effect of coadministered RFP on the concentration of LZD. In animal study in rats, the influence of coadministered RFP on the pharmacokinetics of LZD administered intravenously or orally was examined. Intestinal permeability was investigated with an Ussing chamber to assess whether coadministered RFP alters the absorption process of LZD in the intestine.

Results

Our clinical study indicated that multiple doses of RFP reduced the dose-normalized trough concentration of LZD at the first assessment day by an average of 65%. In an animal study, we found that multiple doses of RFP significantly decreased the area under the concentration-time curve, the maximum concentration and the bioavailability of orally administered LZD by 48%, 54% and 48%, respectively. In contrast, the pharmacokinetics of intravenously administered LZD was unaffected by the RFP pretreatment. However, investigation of the intestinal permeability of LZD revealed no difference in absorptive or secretory transport of LZD in the upper, middle and lower intestinal tissues between RFP-pretreated and control rats, even though RFP induced gene expression of multidrug resistance protein 1a and multidrug resistance-associated protein 2.

Conclusions

Therapeutic drug monitoring may be important for avoiding subtherapeutic levels of LZD in the combination therapy. The drug-drug interaction between LZD and RFP may occur only after oral administration of LZD, but is not due to any change of intestinal permeability of LZD.

Trial registration

UMIN, UMIN000004322. Registered 4 October 2010.

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.

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.

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.

Carbon-free H2 production from ammonia triggered at room temperature with an acidic RuO2/γ-Al2O3 catalyst

Ammonia has been suggested as a carbon-free hydrogen source, but a convenient method for producing hydrogen from ammonia with rapid initiation has not been developed. Ideally, this method would require no external energy input. We demonstrate hydrogen production by exposing ammonia and O₂ at room temperature to an acidic RuO₂/γ-Al₂O₃ catalyst. Because adsorption of ammonia onto the catalyst is exothermic, the catalyst bed is rapidly heated to the catalytic ammonia autoignition temperature, and subsequent oxidative decomposition of ammonia produces hydrogen. A differential calorimeter combined with a volumetric gas adsorption analyzer revealed a large quantity of heat evolved both with chemisorption of ammonia onto RuO₂ and acidic sites on the γ-Al₂O₃ and with physisorption of multiple ammonia molecules.

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.

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.

Maternal Separation Induces Orofacial Mechanical Allodynia in Adulthood

It is well known that exposure to maternal separation (MS) in early life causes plastic changes in the nervous system in adulthood, occasionally resulting in ubiquitous chronic pain. However, the pathogenic mechanisms of pain hypersensitivity remain unclear. Here, the authors examined the involvement of corticosterone in orofacial mechanical hypersensitivity induced by MS. To establish a rat model of MS, pups were placed in isolated cages 180 min/d and kept in a temperature-controlled environment at 22 ± 2 °C for 14 d. Mechanical allodynia in the whisker pad skin in adulthood was induced by MS and was significantly suppressed by successive postnatal subcutaneous administration of the glucocorticoid receptor antagonist mifepristone. Corticosterone levels were increased in the serum of MS rats, and successive postnatal administration of subcutaneous corticosterone to naive rats induced mechanical allodynia in the whisker pad skin. The number of P2X3 receptor-immunoreactive (P2X3R-IR) trigeminal ganglion (TG) neurons innervating the whisker pad skin was significantly increased in MS rats and decreased following subcutaneous administration of mifepristone. The number of P2X3R-IR TG neurons innervating the whisker pad skin was also significantly increased following successive postnatal administration of subcutaneous corticosterone in naive rats. Moreover, the mechanical allodynia was suppressed 30 min after administration of the P2X3R antagonist A317491 to the whisker pad skin in MS rats. These findings suggest that the increase in P2X3R-IR TG neurons innervating the whisker pad skin via enhanced neonatal corticosterone signaling by MS plays an important role in orofacial mechanical allodynia in adulthood.

Immunoglobulin A Nephropathy in a Living Kidney Donor Diagnosed and Treated After Transplantation: A Case Report

OBJECTIVE

We report the clinical course and pathologic findings of a kidney transplant donor who was diagnosed with immunoglobulin A (IgA) nephropathy by means of preimplantation biopsy and was later treated with methylprednisolone and tonsillectomy.

CASE REPORT

The patient was a 57-year-old woman who met the criteria for kidney donation and was accepted as a donor. Donor nephrectomy was performed, and the preimplantation biopsy revealed that the donor had IgA nephropathy. One month after the nephrectomy, the donor's laboratory findings indicated proteinuria and hematuria. Because these findings indicated active IgA nephropathy, we decided to perform tonsillectomy and methylprednisolone pulse therapy. Soon after these treatments, the patient's proteinuria and hematuria were no longer observed.

CONCLUSIONS

Subclinical IgA nephropathy can be incidentally found on preimplantation biopsies of living kidney donors. As demonstrated in this case, IgA nephropathy can become exacerbated and requires therapeutic intervention after kidney donation. Informed consent and careful observation should be used before and after transplantation, even for donors who have been determined to be eligible for kidney donation.

Involvement of Microglial P2Y12 Signaling in Tongue Cancer Pain

To elucidate if microglial P2Y12 receptor (P2Y12R) mechanisms are involved in the trigeminal spinal subnucleus caudalis (Vc; also known as the medullary dorsal horn) in intraoral cancer pain, we developed a rat model of tongue cancer pain. Squamous cell carcinoma (SCC) cells were inoculated into the tongue of rats; sham control rats received the vehicle instead. Nociceptive behavior was measured as the head-withdrawal reflex threshold (HWRT) to mechanical or heat stimulation applied to the tongue under light anesthesia. On day 14 after the SCC inoculation, activated microglia and P2Y12R expression were examined immunohistochemically in the Vc. The HWRT was also studied in SCC-inoculated rats with successive intra-cisterna magna (i.c.m.) administration of specific P2Y12R antagonist (MRS2395) or intraperitoneal administration of minocycline, a microglial activation inhibitor. Tongue cancer was histologically verified in SCC-inoculated rats, within which the HWRT to mechanical stimulation of the tongue was significantly decreased, as compared with that of vehicle-inoculated rats, although the HWRT to heat stimulation was not. Microglia was strongly activated on day 14, and the administration of MRS2395 or minocycline reversed associated nocifensive behavior and microglial activation in SCC-inoculated rats for 14 d. The activity of Vc wide dynamic range nociceptive neurons was also recorded electrophysiologically in SCC-inoculated and sham rats. Background activity and noxious mechanically evoked responses of wide dynamic range neurons were significantly increased in SCC-inoculated rats versus sham rats, and background activity and mechanically evoked responses were significantly suppressed following i.c.m. administration of MRS2395 in SCC-inoculated rats as compared with sham. The present findings suggest that SCC inoculation that produces tongue cancer results in strong activation of microglia via P2Y12 signaling in the Vc, in association with increased excitability of Vc nociceptive neurons, reflecting central sensitization and resulting in tongue mechanical allodynia.

Chemical fragment arrays for rapid druggability assessment

Incorporation of early druggability assessment in the drug discovery process provides a means to prioritize target proteins for high-throughput screening.