• International Journal of Oral Biology
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• v.33 no.4
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• pp.143-147
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• 2008

The sodium bicarbonate cotransporter (NBC) protein is functionally expressed in salivary glands. In this experiment, we examined the role of NBC in $HCO_3^-$ formation in human parotid gland acinar cells. Intracellular pH (pHi) was measured in 2'-7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF)-loaded cells. Acetazolamide (0.1 mM) and 4,4'-diisothio cyanatostilbene-2,2'-disulphonic acid (DIDS, 0.5 mM) were used as specific inhibitors of carbonic anhydrase and NBC, respectively. The degree of inhibition was assessed by measuring the pHi recovery rate (${\Delta}pHi$/min) after cell acidification using an ammonium prepulse technique. In control experiments, ${\Delta}pHi$/min was $1.40{\pm}0.06$. Treatment of cells with 0.5 mM DIDS or 0.1 mM acetazolamide significantly reduced ${\Delta}pHi$/min to $1.14{\pm}0.14$ and $0.74{\pm}0.15$, respectively. Simultaneous application of DIDS and acetazolamide further reduced ${\Delta}pHi$/min to $0.47{\pm}0.10$. Therefore, DIDS and acetazolamide reduced ${\Delta}pHi$/min by 19% and 47%, respectively, while simultaneous application of both DIDS and acetazolamide caused a reduction in ${\Delta}pHi$/min of 67%. These results suggest that in addition to carbonic anhydrase, NBC also partially contributes to $HCO_3^-$ formation in human parotid gland acinar cells.

• Journal of dental hygiene science
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• v.24 no.1
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• pp.37-53
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• 2024

Background: To train dental hygienists to utilize knowledge in practice, an integrated curriculum based on the competencies of dental hygienists is expanding; however, in the field of basic dental hygiene the curriculum is still fragmented and based on segmented knowledge. This study developed an integrated curriculum based on the competencies of dental hygienists in Anatomy, Histology & Embryology, Physiology, which are subjects for basic dental hygiene that have high linkage and overlap. Methods: After selecting the learning objectives for the integrated curriculum from those of Anatomy, Histology & Embryology, Physiology, the duties of the dental hygienist in relation to the learning objectives were analyzed. Learning objectives were combined with the duties of a dental hygienist to derive competencies for an integrated curriculum. Referring to the syllabus and learning objectives for each subject, the weekly educational content, learning objectives, and credits of the integrated curriculum were derived. After conducting a Delphi survey to validate the competency and content of the derived integrated curriculum, an integrated curriculum was developed. Results: By using the first and second Delphi surveys, four competencies were developed for dental hygienists that can be achieved through an integrated basic dental hygiene curriculum. In addition, an integrated curriculum including the courses Anatomy, Histology & Embryology, Physiology, Structure and Function of the Human Body/Head/Neck, and Structure and Function of the Oral Cavity was established. Conclusion: This study presents a specific example for developing a competency-based integrated curriculum that can be used as a framework to derive a competency-based integrated curriculum among subjects that can be integrated according to the linkage of learning contents and the competencies that can be achieved.

• CELLMED
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• v.2 no.1
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• pp.6.1-6.4
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• 2012

The traumatic removal of the mandibular third molar may promote post chirurgic consequences such as orofacial pain and limited mandibular movements. The aim of this case report is to describe the use of an anterior bite plane and complementary therapies (low level laser therapy and acupuncture) to treat the muscular dysfunction and the painful symptoms. A 33 year-old male patient who had a severe malocclusion and signs and symptoms of temporomandibular dysfunction was submitted to an initial clinical examination: electromyography of the masticatory muscles and IRM of the temporomandibular joint. After treatments, the results showed reduced pain symptoms and an increase of the mandibular movements and adequated electromiographic activities. The authors concluded that the combination therapies may be used as an alternative treatment because it satisfied the functional requirements of the patient and provided an asymptomatic clinical condition.

• Journal of Dental Anesthesia and Pain Medicine
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• v.15 no.3
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• pp.129-134
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• 2015

Background: We hypothesized that ketamine, when administered as the anesthetic induction agent, may prevent cardiovascular depression during high-dose remifentanil administration, unlike propofol. To test our hypothesis, we retrospectively compared the hemodynamic effects of ketamine, during high-dose remifentanil administration, with those of propofol. Methods: Thirty-eight patients who underwent oral surgery at the Nagasaki University Hospital between April 2014 and June 2015 were included in this study. Anesthesia was induced by the following procedure: First, high-dose remifentanil ($0.3-0.5{\mu}g/kg/min$) was administered 2-3 min before anesthesia induction;next, the anesthetic induction agent, either propofol (Group P) or ketamine (Group K), was administered. Mean arterial pressure (MAP) and the heart rate were recorded by the automated anesthesia recording system at four time points: immediately before the administration of high-dose remifentanil (T1);immediately before the administration of propofol or ketamine (T2);2.5 min (T3), and 5 min (T4) after the administration of the anesthetic induction agent. Results: In Group P, the MAP at T3 ($75.7{\pm}15.5mmHg$, P = 0.0015) and T4 ($68.3{\pm}12.5mmHg$, P < 0.001) were significantly lower than those at T1 ($94.0{\pm}12.4mmHg$). However, the MAP values in the K group were very similar (P = 0.133) at all time points. The heart rates in both Groups P (P = 0.254) and K (P = 0.859) remained unchanged over time. Conclusions: We showed that ketamine, when administered as the anesthetic induction agent during high-dose remifentanil administration, prevents cardiovascular depression.

• International Journal of Oral Biology
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• v.45 no.3
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• pp.84-91
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• 2020

The present study investigated the participation of D-serine and NR2 in antinociception produced by blockade of central erythropoietin-producing hepatocellular carcinoma (Eph) A4 (EphA4) signaling in rats with trigeminal neuropathic pain. Trigeminal neuropathic pain was modeled in male Sprague-Dawley rats using mal-positioned dental implants. The left mandibular second molar was extracted under anesthesia, and a miniature dental implant was placed to induce injury to the inferior alveolar nerve. Our current findings showed that nerve injury induced by malpositioned dental implants significantly produced mechanical allodynia; additionally, the inferior alveolar nerve injury increased the expression of D-serine and NR2 subunits in the ipsilateral medullary dorsal horn (trigeminal subnucleus caudalis). Intracisternal administration of EphA4-Fc, an EphA4 inhibitor, inhibited nerve injury-induced mechanical allodynia and upregulated the expression of D-serine and NR2 subunits. Moreover, intracisternal administration of D-amino acids oxidase, a D-serine inhibitor, inhibited trigeminal mechanical allodynia. These results show that D-serine and NR2 subunit pathways participate in central EphA4 signaling after an inferior alveolar nerve injury. Therefore, blockade of D-serine and NR2 subunit pathways in central EphA4 signaling provides a new therapeutic target for the treatment of trigeminal neuropathic pain.

• The Journal of the Korean dental association
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• v.16 no.7 s.110
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• pp.537-542
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• 1978

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.6
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• pp.305-309
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• 2002

There are some evidences that $K^+$ efflux evoked by muscarinic stimulation is not mainly mediated by large conductance $K^+$ (BK) channels in salivary gland. In this experiment, we therefore characterised non BK channels in rat submandibular gland acinar cells and examined the possibility of agonist effect on this channel using a patch clamp technique. Two types of $K^+$ channels were observed in these cells. BK channels were observed in 3 cells from total 6 cells and its average conductance was $152{\pm}7$ pS (n=3). The conductance of the another types of $K^+$ channel was estimated as $71{\pm}7$ pS (n=6). On the basis of the conductance of this channel, we defined this channel as intermediate conductance $K^+$ (IK) channels, which were observed from all 6 cells we studied. When we increased $Ca^{2+}$ concentration of the bath solution in inside-out mode, the IK channel activity was greatly increased, suggesting this channel is $Ca^{2+}$ sensitive. We next examined the effect of carbachol (CCh) and isoproterenol on the activity of the IK channels. $10^{-5}$ M isoproterenol significantly increased the open probability (Po) from $0.08{\pm}0.02$ to $0.21{\pm}0.03$ (n=4, P<0.05). Application of $10^{-5}$ M CCh also increased Po from $0.048{\pm}0.03$ to $0.55{\pm}0.33$ (n=5, P<0.05) at the maximum channel activity. The degree of BK channel activation induced by the same concentration of CCh was lower than that of IK channels; Po value was $0.011{\pm}0.003$ and $0.027{\pm}0.005$ in control and during CCh stimulation (n=3), respectively. The result suggests that IK channels exist in salivary acinar cells and its channel activity is regulated by muscaricinic and ${\beta}-adrenergic$ agonist. We conclude that IK channels also play a putative role in secretion as well as the BK channels in rat submandibular gland acinar cells.

• International Journal of Oral Biology
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• v.34 no.1
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• pp.29-36
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• 2009

Cyclosporin A (CsA) has been used clinically as an immunosuppressive drug to prevent organ transplant rejection and in basic research as a mitochondrial permeability blocker. It has been reported that CsA has a protective role in severed neurons and a neurotrophic effect in neuronal cells. However, the molecular mechanisms underlying the stimulation of neuronal cell proliferation by CsA have not yet been elucidated. In our current study, we investigated CsA responsive proteins in PC12 cells using a systematic proteomic approach. The viability of these cells following CsA treatment increased in a dose- and time-dependent manner. Proteins in the CsA-treated PC12 cells were profiled by two-dimensional gel electrophoresis (2-DE) and identified by matrix-assisted laser desorption ionization time-of flight (MALDI-TOF) and electrospray ionization quadupole time-of-flight mass spectrometries (EIQ-TOFMS). This differential expression analysis showed significant changes for 10 proteins (6 up-regulated and 4 down-regulated) upon CsA treatment that were related to cell proliferation, metabolism and the stress response. These proteomics data further our understanding of the proliferation mechanisms of PC12 cells exposed to CsA and demonstrate that our methodology has potential to further elucidate the mechanisms and pathways involved.

• Molecules and Cells
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• v.42 no.2
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• pp.183-188
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• 2019

Osteoarthritis (OA) is a naturally occurring, irreversible disorder and a major health burden. The disease is multifactorial, involving both physiological and mechanical processes, but calcium crystals have been associated intimately with its pathogenesis. This study tested the hypothesis that these crystals have a detrimental effect on the differentiation of osteoclasts and bone homeostasis. This study employed an osteoblastosteoclast coculture system that resembles in vivo osteoblastdependent osteoclast differentiation along with $Ca^{2+}$-phosphate-coated culture dishes. The calcium-containing crystals upregulated the expression of RANKL and increased the differentiation of osteoclasts significantly as a result. On the other hand, osteoblast differentiation was unaffected. MicroRNA profiling showed that dual-specificity phosphatases 1 (DUSP1) was associated with the increased RANKL expression. DUSP1 belongs to a family of MAPK phosphatases and is known to inactivate all three groups of MAPKs, p38, JNK, and ERK. Furthermore, knockdown of DUSP1 gene expression suggested that RANKL expression increases significantly in the absence of DUSP1 regulation. Microarray analysis of the DUSP1 mRNA levels in patients with pathological bone diseases also showed that the downregulated DUSP1 expression leads to increased expression of RANKL and consequently to the destruction of the bone observed in these patients. These findings suggest that calcium-containing crystals may play a crucial role in promoting RANKL-induced osteoclastogenesis via DUSP1.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.2
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• pp.89-95
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• 2018

Background: Incorrect administration of an anesthetic during local anesthesia is one of the most important causes of pain symptoms in patients scheduled for dental procedures. The current study assessed the severity of damage to periodontal tissue following different rates of anesthetic administration. Methods: The research was conducted on 50 outbred male rats with a body mass of 180-240 g. The anesthetic used was 1% articaine. Results: The results showed that administration of the anesthetic at a rapid pace caused structural damage to the periodontal tissue. Further, signs of impaired microcirculation were noted at all rates of administration. Biochemical studies demonstrated changes in the level of glucose and enzymes with the rapid introduction of the anesthetic, indicating severe systemic stress response of the body. Conclusions: Injection of local anesthetic at any rate of introduction induces vascular congestion in the microcirculatory bloodstream and exudative reactions. Rapid introduction of an anesthetic causes progression of structural changes in the gingival tissue.