Body composition and physical activity of university students during COVID-19 lockdowns.

[Purpose] Behavioral restrictions during the corona virus disease 2019 (COVID-19) pandemic may have affected the physical activity levels of college students. We aimed to characterize the body composition and physical activity of college students during these behavioral restrictions. [Participants and Methods] The body composition (height, weight, body mass index, body fat mass, body fat percentage, total body muscle mass, free-fat muscle index [FFMI], and fat mass index [FMI]), physical activity, amount the of walking, amount of daily activity, and the number of steps were measured in 52 university students. [Results] For both male and females, the number of steps taken was lower than the average steps reported by the Ministry of Health, Labour and Welfare. In males, FFMI had a strong positive correlation with physical activity, amount of walking, and the number of steps taken. In females, FFMI had a strong positive correlation with physical activity and the amount of walking, as well as a moderate positive correlation with the amount of daily activity. [Conclusion] Since physical activity and walking of university students during COVID-19 affect FFMI, it is necessary to develop an exercise program that considers behavioral patterns.

Critical contributions of pre-S1 shoulder and distal TRP box in DAG-activated TRPC6 channel by PIP2 regulation.

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2 or PIP2) regulates the activities of numerous membrane proteins, including diacylglycerol(DAG)-activated TRPC3/6/7 channels. Although PIP2 binding is known to support DAG-activated TRP channel activity, its binding site remains unknown. We screened for PIP2 binding sites within TRPC6 channels through extensive mutagenesis. Using voltage-sensitive phosphatase (DrVSP), we found that Arg437 and Lys442, located in the channel's pre-S1 domain/shoulder, are crucial for interaction with PIP2. To gain structural insights, we conducted computer protein-ligand docking simulations with the pre-S1 domain/shoulder of TRPC6 channels. Further, the functional significance of PIP2 binding to the pre-S1 shoulder was assessed for receptor-operated channel functions, cross-reactivity to DAG activation, and the kinetic model simulation. These results revealed that basic residues in the pre-S1 domain/shoulder play a central role in the regulation of PIP2-dependent gating. In addition, neutralizing mutation of K771 in the distal TRP box reversed the effect of PIP2 depletion from inhibiting to potentiating channel activity. A similar effect was seen in TRPV1 channels, which suggests that TRPC6 possesses a common but robust polarity switch mediating the PIP2-dependent effect. Overall, these mutagenesis studies reveal functional and structural insights for how basic residues and channel segments in TRP channels are controlled through phosphoinositides recognition.

Opportune Time of Tooth Extraction in Individuals Requiring Ventricular Assist Device Implantation: A Retrospective Cohort Study.

PURPOSE: Individuals with implantable ventricular assist devices (VADs) are at extremely high risk of bleeding, thromboembolism, and infection after undergoing invasive dental procedures. This study aimed to investigate the systemic and local complications of tooth extraction before and after VAD implantation. PATIENTS AND METHODS: This retrospective cohort study was conducted at a single center. Oral surgical procedures were performed in patients before and/or after left VAD implantation for bridge-to-heart transplantation between April 2013 and December 2017. In this study, the medical charts of the patients were retrospectively reviewed. Data about pre-extraction complete blood count, coagulation profile, biochemical profile, and incidence of local and systemic complications were compared in patients undergoing tooth extraction before VAD implantation (b-VAD group) versus after VAD implantation (a-VAD group). RESULTS: In total, 28 inpatients underwent 36 oral surgical procedures before and/or after VAD implantation. Moreover, 24 tooth extractions were performed in the b-VAD group, and 12 were performed in the a-VAD group. The incidence of post-extraction bleeding was higher in the a-VAD group (P = .001, Mann-Whitney U test), and a significant difference was observed in terms of activated partial thromboplastin time (P = .010, Mann-Whitney U test). Systemic complications associated with VADs included cerebral infarction (n = 2) and driveline infection (n = 1). Post-extraction bleeding was observed within 90 days after VAD implantation in all patients who underwent tooth extraction. CONCLUSIONS: The risk of bleeding after tooth extraction was higher in the a-VAD group (67%) than in the b-VAD group (13%). In 3 cases, VAD-related systemic complications developed within a short period after tooth extraction. The extraction management in the b-VAD group could be controlled without causing any problem. Hence, the opportune time of tooth extraction is before VAD implantation.

A Cross-Sectional Study of Age-Related Changes in Oral Function in Healthy Japanese Individuals.

BACKGROUND: Oral function deterioration is related to a variety of factors, including aging, decline in activities of daily living, malnutrition, and cognitive decline. This cross-sectional study examined the effects of aging on oral function in healthy individuals. METHODS: A retrospective study was conducted on 175 healthy, independent patients aged 40-89 years, without dementia and with ≥20 teeth, who visited a local dental clinic in Japan. Patients were compared with 92 university students aged 20-29 years. The seven criteria proposed by the Japanese Society of Gerodontology to diagnose "oral hypofunction" were observed and statistically analyzed. RESULTS: Compared with those in the control group, the degree of tongue coating was increased in the group aged over 80 years, occlusal force was decreased in the group aged 70-79 years, tongue motor function was decreased in the groups aged 60-69 years and older, and tongue pressure was decreased in the groups aged 70-79 years and older. CONCLUSIONS: Healthy, independent individuals maintained several oral function criteria across aging, including oral mucosal wetness, occlusal force, lip motor function, masticatory function, and swallowing function. Tongue motor function and tongue pressure decreased with aging, indicating that these may be rehabilitation targets.

Applying orthodontic tooth extrusion in a patient treated with bisphosphonate and irradiation: a case report.

Bisphosphonates and irradiation are useful medical treatments, but can often cause oral complications such as medication-related oral necrosis of the jaw (MRONJ) and osteoradionecrosis (ORN) during oral surgery, including tooth extraction. Therefore, we should take all risks into consideration carefully before choosing dental treatment for patients with a medical history of such therapies. A 55-year-old woman who underwent cord blood transplantation to treat extranodal natural killer T (NK/T) cell lymphoma (nasal type IVB) had a medical history of bisphosphonate and irradiation treatments. We treated her residual tooth root by applying orthodontic extrusion to avoid extraction and successfully restored the tooth. Application of an orthodontic tooth extrusion technique for conservative treatment of a residual tooth is a useful means of avoiding MRONJ or ORN in patients who have a medical history of bisphosphonate and irradiation treatments.

Surface vacuolar ATPase in ameloblastoma contributes to tumor invasion of the jaw bone.

Ameloblastoma is the most common benign odontogenic tumor in Japan. It is believed that it expands in the jaw bone through peritumoral activation of osteoclasts by receptor activator of nuclear factor kappa-B ligand (RANKL) released from the ameloblastoma, as in bone metastases of cancer cells. However, the clinical features of ameloblastoma, including its growth rate and patterns of invasion, are quite different from those of bone metastasis of cancer cells, suggesting that different underlying mechanisms are involved. Therefore, in the present study, we examined the possible mechanisms underlying the invasive expansion of ameloblastoma in the jaw bone. Expression levels of RANKL assessed by western blotting were markedly lower in ameloblastoma (AM-1) cells than in highly metastatic oral squamous cell carcinoma (HSC-3) cells. Experiments coculturing mouse macrophages (RAW264.7) with AM-1 demonstrated low osteoclastogenic activity, as assessed by tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cell formation, probably because of low release of RANKL, whereas cocultures of RAW264.7 with HSC-3 cells exhibited very high osteoclastogenic activity. Thus, RANKL release from AM-1 appeared to be too low to generate osteoclasts. However, AM-1 cultured directly on calcium phosphate-coated plates formed resorption pits, and this was inhibited by application of bafilomycin A1. Furthermore, vacuolar-type H+-ATPase (V-ATPase) and H+/Cl- exchange transporter 7 (CLC-7) were detected on the surface of AM-1 cells by plasma membrane biotinylation and immunofluorescence analysis. Immunohistochemical analysis of clinical samples of ameloblastoma also showed plasma membrane-localized V-ATPase and CLC-7 in the epithelium of plexiform, follicular and basal cell types. The demineralization activity of AM-1 was only 1.7% of osteoclasts demineralization activity, and the growth rate was 20% of human normal skin keratinocytes and HSC-3 cells. These results suggest that the slow expansion of several typical types of ameloblastomas in jaw bone is attributable to its slow growth and low demineralization ability.

Targeted sonography using an image fusion technique for evaluation of incidentally detected breast lesions on chest CT: a pilot study.

BACKGROUND: With increasing use of computed tomography (CT), incidentally detected breast lesions are being encountered more frequently. The aim of our study was to verify the utility of targeted sonography using an image fusion technique, real-time virtual sonography (RVS) that coordinates real-time sonography images with previously obtained CT images using a magnetic position tracking system, for evaluation of incidentally detected breast lesions on chest CT. METHODS: Eleven lesions in 11 women with no history of breast cancer who were referred to our unit for assessment of breast lesions incidentally detected on CT were enrolled in this study. To assess the efficacy of targeted sonography using RVS, we analyzed the frequency of sonographic detection of incidentally detected breast lesions and the difference between sonography- and CT-determined diameters. RESULTS: Using RVS guidance, all 11 lesions were sonographically detected. Ten (91 %) of 11 lesions underwent sonography-guided biopsy, yielding a success rate of 90 % (9/10). The remaining sonography-guided biopsy failure lesion required surgical biopsy for definitive diagnosis; this was performed after RVS was used to mark CT imaging information onto the breast surface. Four (36 %) lesions subsequently proved to be malignant. The mean diameters provided by RVS were 14.9 ± 6.7 mm for sonography and 16.8 ± 7.5 mm for CT (p = 0.538). CONCLUSION: Using RVS, a sonographic probe was precisely guided to the lesions. Our results suggest that targeted sonography using RVS is a useful technique for identifying incidentally detected breast lesions on chest CT.

Tooth extraction in patients taking nonvitamin K antagonist oral anticoagulants.

BACKGROUND/PURPOSE: The nonvitamin K antagonist oral anticoagulants direct-thrombin inhibitor dabigatran and the Xa inhibitors rivaroxaban and apixaban are now being used clinically. The course of the patients on these anticoagulants who underwent tooth extraction was assessed. MATERIALS AND METHODS: The medical charts of these patients were investigated. Tooth extraction was performed while maintaining conventional anticoagulant therapy. RESULTS: Twenty-three teeth were extracted in 19 patients, including two surgical extractions. Among the 19 patients, nine patients ingested rivaroxaban, six apixaban, and four dabigatran. One patient on rivaroxaban showed persistent postoperative bleeding following two surgical extractions. Mild oozing was observed in five patients (two on rivaroxaban and three on apixaban). There was no bleeding episode in the patients on dabigatran. CONCLUSION: The patients on rivaroxaban with a prolonged prothrombin time value have a higher risk of bleeding, especially undergoing surgical extraction. Apixaban correlates to neither activated partial thromboplastin time nor prothrombin time values and the countermeasures should be employed based on the clinical findings.

PLC-mediated PI(4,5)P2 hydrolysis regulates activation and inactivation of TRPC6/7 channels.

Transient receptor potential classical (or canonical) (TRPC)3, TRPC6, and TRPC7 are a subfamily of TRPC channels activated by diacylglycerol (DAG) produced through the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) by phospholipase C (PLC). PI(4,5)P2 depletion by a heterologously expressed phosphatase inhibits TRPC3, TRPC6, and TRPC7 activity independently of DAG; however, the physiological role of PI(4,5)P2 reduction on channel activity remains unclear. We used Förster resonance energy transfer (FRET) to measure PI(4,5)P2 or DAG dynamics concurrently with TRPC6 or TRPC7 currents after agonist stimulation of receptors that couple to Gq and thereby activate PLC. Measurements made at different levels of receptor activation revealed a correlation between the kinetics of PI(4,5)P2 reduction and those of receptor-operated TRPC6 and TRPC7 current activation and inactivation. In contrast, DAG production correlated with channel activation but not inactivation; moreover, the time course of channel inactivation was unchanged in protein kinase C-insensitive mutants. These results suggest that inactivation of receptor-operated TRPC currents is primarily mediated by the dissociation of PI(4,5)P2. We determined the functional dissociation constant of PI(4,5)P2 to TRPC channels using FRET of the PLCδ Pleckstrin homology domain (PHd), which binds PI(4,5)P2, and used this constant to fit our experimental data to a model in which channel gating is controlled by PI(4,5)P2 and DAG. This model predicted similar FRET dynamics of the PHd to measured FRET in either human embryonic kidney cells or smooth muscle cells, whereas a model lacking PI(4,5)P2 regulation failed to reproduce the experimental data, confirming the inhibitory role of PI(4,5)P2 depletion on TRPC currents. Our model also explains various PLC-dependent characteristics of channel activity, including limitation of maximum open probability, shortening of the peak time, and the bell-shaped response of total current. In conclusion, our studies demonstrate a fundamental role for PI(4,5)P2 in regulating TRPC6 and TRPC7 activity triggered by PLC-coupled receptor stimulation.

Cylindrical corrective osteotomy for Madelung deformity using a computer simulation: case report.

We report an adolescent patient with Madelung deformity that we successfully treated by cylindrical corrective osteotomy of the distal radius. We used customized surgical guides, which were designed based on preoperative 3-dimensional computer simulation.

Voltage-sensing phosphatase reveals temporal regulation of TRPC3/C6/C7 channels by membrane phosphoinositides.

TRPC3/C6/C7 channels, a subgroup of classical/canonical TRP channels, are activated by diacylglycerol produced via activation of phospholipase C (PLC)-coupled receptors. Recognition of the physiological importance of these channels has been steadily growing, but the mechanism by which they are regulated remains largely unknown. We recently used a membrane-resident danio rerio voltage-sensing phosphatase (DrVSP) to study TRPC3/C6/C7 regulation and found that the channel activity was controlled by PtdIns(4,5)P(2)-DAG signaling in a self-limiting manner (Imai Y et al., the Journal of Physiology, 2012). In this addendum, we present the advantages of using DrVSP as a molecular tool to study PtdIns(4,5)P(2) regulation. DrVSP should be readily applicable for studying phosphoinositide metabolism-linked channel regulation as well as lipid dynamics. Furthermore, in comparison to other modes of self-limiting ion channel regulation, the regulation of TRPC3/C6/C7 channels seems highly susceptible to activation signal strength, which could potentially affect both open duration and the time to peak activation and inactivation. Dysfunction of such self-limiting regulation may contribute to the pathology of the cardiovascular system, gastrointestinal tract and brain, as these channels are broadly distributed and affected by numerous neurohormonal agonists.

A self-limiting regulation of vasoconstrictor-activated TRPC3/C6/C7 channels coupled to PI(4,5)P2-diacylglycerol signalling.

Activation of transient receptor potential (TRP) canonical TRPC3/C6/C7 channels by diacylglycerol (DAG) upon stimulation of phospholipase C (PLC)-coupled receptors results in the breakdown of phosphoinositides (PIPs). The critical importance of PIPs to various ion-transporting molecules is well documented, but their function in relation to TRPC3/C6/C7 channels remains controversial. By using an ectopic voltage-sensing PIP phosphatase (DrVSP), we found that dephosphorylation of PIPs robustly inhibits currents induced by carbachol (CCh), 1-oleolyl-2-acetyl-sn-glycerol (OAG) or RHC80267 in TRPC3, TRPC6 and TRPC7 channels, though the strength of the DrVSP-mediated inhibition (VMI) varied among the channels with a rank order of C7>C6>C3. Pharmacological and molecular interventions suggest that depletion of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is most likely the critical event for VMI in all three channels.When the PLC catalytic signal was vigorously activated through overexpression of the muscarinic type-I receptor (M1R), the inactivation of macroscopic TRPC currents was greatly accelerated in the same rank order as the VMI, and VMI of these currents was attenuated or lost. VMI was also rarely detected in vasopressin-induced TRPC6-like currents inA7r5 vascular smooth muscle cells, indicating that the inactivation by PI(4,5)P2 depletion underlies the physiological condition. Simultaneous fluorescence resonance energy transfer (FRET)-based measurement of PI(4,5)P2 levels and TRPC6 currents confirmed that VMI magnitude reflects the degree of PI(4,5)P2 depletion. These results demonstrate that TRPC3/C6/C7 channels are differentially regulated by depletion of PI(4,5)P2, and that the bimodal signal produced by PLC activation controls these channels in a self-limiting manner.

Counteracting effect of TRPC1-associated Ca2+ influx on TNF-α-induced COX-2-dependent prostaglandin E2 production in human colonic myofibroblasts.

TNF-α-NF-κB signaling plays a central role in inflammation, apoptosis, and neoplasia. One major consequence of this signaling in the gut is increased production of prostaglandin E(2) (PGE(2)) via cyclooxygenase-2 (COX-2) induction in myofibroblasts, which has been reported to be dependent on Ca(2+). In this study, we explored a potential role of canonical transient receptor potential (TRPC) proteins in this Ca(2+)-mediated signaling using a human colonic myofibroblast cell line CCD-18Co. In CCD-18Co cell, treatment with TNF-α greatly enhanced Ca(2+) influx induced by store depletion along with increased cell-surface expression of TRPC1 protein (but not of the other TRPC isoforms) and induction of a Gd(3+)-sensitive nonselective cationic conductance. Selective inhibition of TRPC1 expression by small interfering RNA (siRNA) or functionally effective TRPC1 antibody targeting the near-pore region of TRPC1 (T1E3) antagonized the enhancement of store-dependent Ca(2+) influx by TNF-α, whereas potentiated TNF-α induced PGE(2) production. Overexpression of TRPC1 in CCD-18Co produced opposite consequences. Inhibitors of NF-κB (curcumin, SN-50) attenuated TNF-α-induced enhancement of TRPC1 expression, store-dependent Ca(2+) influx, and COX-2-dependent PGE(2) production. In contrast, inhibition of calcineurin-nuclear factor of activated T-cell proteins (NFAT) signaling by FK506 or NFAT Activation Inhibitor III enhanced the PGE(2) production without affecting TRPC1 expression and the Ca(2+) influx. Finally, the suppression of store-dependent Ca(2+) influx by T1E3 antibody or siRNA knockdown significantly facilitated TNF-α-induced NF-κB nuclear translocation. In aggregate, these results strongly suggest that, in colonic myofibroblasts, NF-κB and NFAT serve as important positive and negative transcriptional regulators of TNF-α-induced COX-2-dependent PGE(2) production, respectively, at the downstream of TRPC1-associated Ca(2+) influx.

Quantitative measurement of Ca(2+)-dependent calmodulin-target binding by Fura-2 and CFP and YFP FRET imaging in living cells.

Calcium dynamics and its linked molecular interactions cause a variety of biological responses; thus, exploiting techniques for detecting both concurrently is essential. Here we describe a method for measuring the cytosolic Ca(2+) concentration ([Ca(2+)](i)) and protein-protein interactions within the same cell, using Fura-2 and superenhanced cyan and yellow fluorescence protein (seCFP and seYFP, respectively) FRET imaging techniques. Concentration-independent corrections for bleed-through of Fura-2 into FRET cubes across different time points and [Ca(2+)](i) values allowed for an effective separation of Fura-2 cross-talk signals and seCFP and seYFP cross-talk signals, permitting calculation of [Ca(2+)](i) and FRET with high fidelity. This correction approach was particularly effective at lower [Ca(2+)](i) levels, eliminating bleed-through signals that resulted in an artificial enhancement of FRET. By adopting this correction approach combined with stepwise [Ca(2+)](i) increases produced in living cells, we successfully elucidated steady-state relationships between [Ca(2+)](i) and FRET derived from the interaction of seCFP-tagged calmodulin (CaM) and the seYFP-fused CaM binding domain of myosin light chain kinase. The [Ca(2+)](i) versus FRET relationship for voltage-gated sodium, calcium, and TRPC6 channel CaM binding domains (IQ domain or CBD) revealed distinct sensitivities for [Ca(2+)](i). Moreover, the CaM binding strength at basal or subbasal [Ca(2+)](i) levels provided evidence of CaM tethering or apoCaM binding in living cells. Of the ion channel studies, apoCaM binding was weakest for the TRPC6 channel, suggesting that more global Ca(2+) and CaM changes rather than the local CaM-channel interface domain may be involved in Ca(2+)CaM-mediated regulation of this channel. This simultaneous Fura-2 and CFP- and YFP-based FRET imaging system will thus serve as a simple but powerful means of quantitatively elucidating cellular events associated with Ca(2+)-dependent functions.

Regulation of cardiovascular TRP channel functions along the NO-cGMP-PKG axis.

There is growing body of evidence that nitric oxide (NO)-cGMP-PKG signaling plays a central role in negative regulation of cardiovascular (CV) responses and its disorders through suppressed Ca(2+) dynamics. Other lines of evidence also reveal the stimulatory effects of this signaling on some CV functions. Recently, transient receptor potential (TRP) channels have received much attention as non-voltage-gated Ca(2+) channels involved in CV physiology and pathophysiology. Available information suggests that these channels undergo both inhibition and activation by NO via PKG-mediated phosphorylation and S-nitrosylation, respectively, and also act as upstream regulators to promote endothelial NO production. This review summarizes the roles of NO-cGMP-PKG signaling pathway, particularly in regulating TRP channel functions with their associated physiology and pathophysiology.

Influence of the electron acceptor on nitrite reductase gene (nir) diversity in an activated sludge community.

Analyses of the nitrite reductase gene diversities (nirK and nirS) in an activated sludge community fed with both nitrite and glucose were conducted. Results suggest that the topology of nirK and nirS gene fragment-based phylogenetic trees is influenced more by the available electron acceptor than by the carbon source. A denitrification reactor was operated for 53 days and a clone library constructed when the denitrifying communities in the SBR were supplied with both nitrite and glucose. Half of the nirK and nearly all the nirS gene fragments formed a cluster that was separate from a cluster containing nirK and nirS sequences derived from other communities in nitrate-fed reactors. On the other hand, nirK and nirS fragments obtained with glucose as the carbon source were similar to those detected in communities fed with other carbon sources.