Evaluation of a Proton Pump Inhibitor for Sleep Bruxism: A Randomized Clinical Trial.

Bruxism is a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or bracing or thrusting of the mandible. Recent advances have clarified the relationship between gastroesophageal reflux and sleep bruxism (SB). However, the influence of pharmacological elimination of gastric acid secretion on SB has not been confirmed. The authors aimed to assess the efficacy of a proton pump inhibitor (PPI) on SB and to examine the gastrointestinal (GI) symptoms and endoscopic findings of the upper GI tract in SB patients. The authors performed a randomized double-blind placebo-controlled crossover study at Kagoshima University Hospital. Twelve patients with polysomnography (PSG)-diagnosed SB underwent an assessment of GI symptoms using the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG) and esophagogastroduodenoscopy. At baseline (i.e., before interventions), the mean frequencies of electromyography (EMG) bursts and rhythmic masticatory muscle activity (RMMA) episodes were 65.4 ± 49.0 bursts/h and 7.0 ± 4.8 episodes/h, respectively, and at least 1 RMMA episode with grinding noise was confirmed in all participants. The mean FSSG score was 8.4 ± 5.6, and 41.7% of patients were diagnosed with gastroesophageal reflux disease. Mild reflux esophagitis was confirmed in 6 patients. PSG, including EMG of the left masseter muscle and audio-video recording, was performed on days 4 and 5 of administration of 10 mg of the PPI (rabeprazole) or placebo. PPI administration yielded a significant reduction in the frequency of EMG bursts, RMMA episodes, and grinding noise. No significant differences were observed regarding the swallowing events and sleep variables. Since the clinical application of PPI for SB treatment should remain on hold at present, the results of this trial highlight the potential application of pharmacological gastroesophageal reflux disease treatment for SB patients. Larger scale studies are warranted to corroborate these findings. (UMIN Clinical Trials Registry: UMIN000004577).

Imaging mass spectrometry detects dynamic changes of phosphatidylcholine in rat hippocampal CA1 after transient global ischemia.

BACKGROUND AND PURPOSE: The initial steps in the cascade leading to cell death are still unknown because of the limitations of the existing methodology, strategy, and modalities used. METHODS: Imaging mass spectrometry (IMS) was used to measure dynamic molecular changes of phosphatidylcholine (PC) species in the rat hippocampus after transient global ischemia (TGI) for 6min. Fresh frozen sections were obtained after euthanizing the rats on Days 1, 2, 4, 7, 10, 14, and 21. Histopathology and IMS of adjacent sections compared morphological and molecular changes, respectively. RESULTS: Histopathological changes were absent immediately after TGI (at Day 1, superacute phase). At Days 2-21 after TGI (from subacute to chronic phases), histopathology revealed neuronal death associated with gliosis, inflammation, and accumulation of activated microglia in CA1. IMS detected significant molecular changes after TGI in the same CA1 domain: increase of PC (diacyl-16:0/22:6) in the superacute phase and increase of PC (diacyl-16:0/18:1) in the subacute to chronic phases. CONCLUSIONS: Histopathology and IMS can provide comprehensive and complementary information on cell death mechanisms in the hippocampal CA1 after global ischemia. IMS provided novel data on molecular changes in phospholipids immediately after TGI. Increased level of PC (diacyl-16:0/22:6) in the pyramidal cell layer of hippocampal CA1 prior to the histopathological change may represent an early step in delayed neuronal death mechanisms.

Facial pigmentation as a biomarker of carotid atherosclerosis in middle-aged to elderly healthy Japanese subjects.

BACKGROUND/PURPOSE: Perceived age may be a better predictor of mortality rate than chronological age. We have demonstrated that perceived age was a significant biomarker for carotid atherosclerosis in Japanese. However, it remains to be determined which skin parameter is associated with atherosclerosis. The purpose of this study is to analyze the relationship between 10 facial skin-aging parameters and atherosclerosis in 169 middle-aged to elderly Japanese women who participated. METHODS: Facial photographs were taken under a shadowless lamp from three directions using a high-resolution digital camera. The digital images of each subject were analyzed using computer software and various parameters of skin aging such as pigmentation, wrinkles, and skin color were quantified. Carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) were measured as indices for atherosclerosis. RESULTS: Facial pigmentation showed a significant correlation with carotid IMT, even after correction for age (r = 0.13, P = 0.03), and with visceral fat area. Stepwise regression analysis indicated that facial pigmentation was associated with carotid IMT via visceral fat area. CONCLUSION: Facial pigmentation may be a useful biomarker for carotid atherosclerosis in Japanese women.

Influence of surgical orthodontic treatment on masticatory function in skeletal Class III patients.

Skeletal Class III patients exhibit malocclusion characterised by Angle Class III and anterior crossbite, and their occlusion shows total or partially lateral crossbite of the posterior teeth. Most patients exhibit lower bite force and muscle activity than non-affected subjects. While orthognathic surgery may help improve masticatory function in these patients, its effects have not been fully elucidated. The aims of the study were to evaluate jaw movement and the electromyographic (EMG) activity of masticatory muscles before and after orthognathic treatment in skeletal Class III patients in comparison with control subjects with normal occlusion. Jaw movement variables and EMG data were recorded in 14 female patients with skeletal Class III malocclusion and 15 female controls with good occlusion. Significant changes in jaw movement, from a chopping to a grinding pattern, were observed after orthognathic treatment (closing angle P < 0.01; cycle width P < 0.01), rendering jaw movement in the patient group similar to that of the control group. However, the grinding pattern in the patient group was not as broad as that of controls. The activity indexes, indicating the relative contributions of the masseter and temporalis muscles (where a negative value corresponds to relatively more temporalis activity and vice versa) changed from negative to positive after treatment (P < 0.05), becoming similar to those of control subjects. Our findings suggest that orthognathic treatment in skeletal Class III patients improves the masticatory chewing pattern and muscle activity. However, the chewing pattern remains incomplete compared with controls.

Markedly improved outcomes and acceptable toxicity in adolescents and young adults with acute lymphoblastic leukemia following treatment with a pediatric protocol: a phase II study by the Japan Adult Leukemia Study Group.

The superiority of the pediatric protocol for adolescents with acute lymphoblastic leukemia (ALL) has already been demonstrated, however, its efficacy in young adults remains unclear. The ALL202-U protocol was conducted to examine the efficacy and feasibility of a pediatric protocol in adolescents and young adults (AYAs) with BCR-ABL-negative ALL. Patients aged 15-24 years (n=139) were treated with the same protocol used for pediatric B-ALL. The primary objective of this study was to assess the disease-free survival (DFS) rate and its secondary aims were to assess toxicity, the complete remission (CR) rate and the overall survival (OS) rate. The CR rate was 94%. The 5-year DFS and OS rates were 67% (95% confidence interval (CI) 58-75%) and 73% (95% CI 64-80%), respectively. Severe adverse events were observed at a frequency that was similar to or lower than that in children treated with the same protocol. Only insufficient maintenance therapy significantly worsened the DFS (hazard ratio 5.60, P<0.001). These results indicate that this protocol may be a feasible and highly effective treatment for AYA with BCR-ABL-negative ALL.

First molar cross-bite is more closely associated with a reverse chewing cycle than anterior or pre-molar cross-bite during mastication.

A posterior cross-bite is defined as an abnormal bucco-lingual relationship between opposing molars, pre-molars or both in centric occlusion. Although it has been reported that patients with unilateral posterior cross-bite often show unique chewing patterns, the relationship between the form of cross-bite and masticatory jaw movement remains unclear in adult patients. The objective of this study was to investigate masticatory jaw movement among different forms of cross-bite. One hundred and one adults were recruited in this study: 27 had unilateral first molar cross-bite (MC group); 28, unilateral pre-molar cross-bite (PC group); 23, anterior cross-bite (AC group); and 23, normal occlusion (control group). Masticatory jaw movement of the lower incisor point was recorded with six degrees of freedom jaw-tracking system during unilateral mastication. Our results showed that the reverse chewing ratio during deliberate unilateral mastication was significantly larger in the MC group than in the PA (P < 0.001), AC (P < 0.001) and control (P < 0.001) groups. These findings suggest that compared to the anterior or pre-molar cross-bite, the first molar cross-bite is more closely associated with a higher prevalence of a reverse chewing cycle.

Influence of experimental oesophageal acidification on masseter muscle activity, cervicofacial behaviour and autonomic nervous activity in wakefulness.

Recent studies have been revealing the relationship between the stomatognathic system and the gastrointestinal tract. However, the effect of oesophageal acid stimulation on masticatory muscle activity during wakefulness has not been fully elucidated. To examine whether intra-oesophageal acidification induces masticatory muscle activity, a randomised trial was conducted investigating the effect of oesophageal acid infusion on masseter muscle activity, autonomic nervous system (ANS) activity and subjective symptoms. Polygraphic monitoring consisting of electromyography of the masseter muscle, electrocardiography and audio-video recording was performed in 15 healthy adult men, using three different 30-min interventions: (i) no infusion, (ii) intra-oesophageal saline infusion and (iii) intra-oesophageal infusion of acidic solution (0·1 N HCl; pH 1·2). This study was registered with the UMIN Clinical Trials Registry, UMIN000005350. Oesophageal acid stimulation significantly increased masseter muscle activity during wakefulness, especially when no behaviour was performed in the oro-facial region. Chest discomfort, including heartburn, also increased significantly after oesophageal acid stimulation; however, no significant correlation was observed between increased subjective symptoms and masseter muscle activity. Oesophageal acid infusion also altered ANS activity; a significant correlation was observed between masticatory muscle changes and parasympathetic nervous system activity. These findings suggest that oesophageal-derived ANS modulation induces masseter muscle activity, irrespective of the presence or absence of subjective gastrointestinal symptoms.

Posterior scissors-bite: masticatory jaw movement and muscle activity.

Scissors-bite is a malocclusion characterised by buccal inclination or buccoversion of the maxillary posterior tooth and/or linguoclination or linguoversion of the mandibular posterior tooth. This type of malocclusion causes reduced contact of the occlusal surfaces and can cause excessive vertical overlapping of the posterior teeth. This case-control study is the first to evaluate both masticatory jaw movement and masseter and temporalis muscle activity in patients with unilateral posterior scissors-bite. Jaw movement variables and surface electromyography data were recorded in 30 adult patients with unilateral posterior scissors-bite malocclusion and 18 subjects with normal occlusion in a case-control study. The chewing pattern on the scissors-bite side significantly differed from that of the non-scissors-bite side in the patients and of the right side in the normal subjects. These differences included a narrower chewing pattern (closing angle, P < 0.01; cycle width, P < 0.01), a longer closing duration (P < 0.05), a slower closing velocity (P < 0.01) and lower activities of both the temporalis (P < 0.05) and the masseter (P < 0.05) muscles on the working side. In 96% of the patients with unilateral posterior scissors-bite, the preferred chewing side was the non-scissors-bite side (P = 0.005). These findings suggest that scissors-bite malocclusion is associated with the masticatory chewing pattern and muscle activity, involving the choice of the preferred chewing side in patients with unilateral posterior scissors-bite.

Influence of maximum bite force on jaw movement during gummy jelly mastication.

It is known that maximum bite force has various influences on chewing function; however, there have not been studies in which the relationships between maximum bite force and masticatory jaw movement have been clarified. The aim of this study was to investigate the effect of maximum bite force on masticatory jaw movement in subjects with normal occlusion. Thirty young adults (22 men and 8 women; mean age, 22.6 years) with good occlusion were divided into two groups based on whether they had a relatively high or low maximum bite force according to the median. The maximum bite force was determined according to the Dental Prescale System using pressure-sensitive sheets. Jaw movement during mastication of hard gummy jelly (each 5.5 g) on the preferred chewing side was recorded using a six degrees of freedom jaw movement recording system. The motion of the lower incisal point of the mandible was computed, and the mean values of 10 cycles (cycles 2-11) were calculated. A masticatory performance test was conducted using gummy jelly. Subjects with a lower maximum bite force showed increased maximum lateral amplitude, closing distance, width and closing angle; wider masticatory jaw movement; and significantly lower masticatory performance. However, no differences in the maximum vertical or maximum anteroposterior amplitudes were observed between the groups. Although other factors, such as individual morphology, may influence masticatory jaw movement, our results suggest that subjects with a lower maximum bite force show increased lateral jaw motion during mastication.

Comprehensive analysis of genetic alterations and their prognostic impacts in adult acute myeloid leukemia patients.

To clarify the cooperative roles of recurrently identified mutations and to establish a more precise risk classification system in acute myeloid leukemia (AML), we comprehensively analyzed mutations in 51 genes, as well as cytogenetics and 11 chimeric transcripts, in 197 adult patients with de novo AML who were registered in the Japan Adult Leukemia Study Group AML201 study. We identified a total of 505 mutations in 44 genes, while only five genes, FLT3, NPM1, CEBPA, DNMT3A and KIT, were mutated in more than 10% of the patients. Although several cooperative and exclusive mutation patterns were observed, the accumulated mutation number was higher in cytogenetically normal AML and lower in AML with RUNX1-RUNX1T1 and CBFB-MYH11, indicating a strong potential of these translocations for the initiation of AML. Furthermore, we evaluated the prognostic impacts of each sole mutation and the combinations of mutations and/or cytogenetics, and demonstrated that AML patients could be clearly stratified into five risk groups for overall survival by including the mutation status of DNMT3A, MLL-PTD and TP53 genes in the risk classification system of the European LeukemiaNet. These results indicate that the prognosis of AML could be stratified by the major mutation status in combination with cytogenetics.

Visceral varicella zoster virus infection after allogeneic stem cell transplantation.

INTRODUCTION: Varicella zoster virus (VZV) disease is one of the major infectious complications that can occur after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Many reports have shown visceral VZV infection, a special type of VZV disease, to be rare. However, few studies so far have included a large number of patients. FINDINGS: Visceral VZV infection was found in 20 (0.8%) of 2411 patients who underwent allo-HSCT at our hospitals. Seventeen (85%) patients were taking immunosuppressive agents at the time of presentation with zoster. The presenting symptom was abdominal pain in 16 patients (80%), unconsciousness in 3 patients (15%), and no symptoms in 1 patient. The mean time interval from allo-HSCT to symptomatic visceral VZV infection was 273 days (103-800 days). The eruptions appeared within 3 days (0-13) after the first symptoms. Treatment with intravenous acyclovir was initiated before the appearance of eruptions in 3 of 18 patients (all 3 survived) with vesicular eruptions, the same day in 12 patients (11 survived, 1 died), and after the appearance in 3 patients (1 survived, 2 died). The overall mortality was 20%. CONCLUSION: In conclusion, these data confirm that the incidence of visceral VZV infection is infrequent, but this disease is serious. When patients being treated with immunosuppressive agents demonstrate abdominal pain or unconsciousness, the possibility of visceral VZV infection should be considered as well as earlier therapeutic intervention.

The role of HLA-matched unrelated transplantation in adult patients with Ph chromosome-negative ALL in first remission. A decision analysis.

The efficacy of unrelated transplantation for patients with ALL who lack an HLA-matched sibling remains unclear. We performed a decision analysis to determine the efficacy of myeloablative transplantation from a genetically HLA-A, -B, -DRB1 allele-matched unrelated donor for patients with Ph chromosome-negative ALL aged 21-54 years. The transition probabilities were estimated from the Japan Adult Leukemia Study Group studies (ALL93; n=80, ALL97; n=82), and the Japan Marrow Donor Program database (transplantation in first CR (CR1): n=177). The primary outcome measure was the 10-year survival probability with or without quality of life (QOL) adjustment. Subgroup analyses were performed according to risk stratification based on the WBC count and cytogenetics, and according to age stratification. In all patients, unrelated transplantation in CR1 was shown to be superior in analyses both with and without QOL adjustment (40.8 vs 28.4% and 43.9 vs 29.0%, respectively). A similar tendency was observed in all subgroups. The decision model was sensitive to the probability of leukemia-free survival following chemotherapy and the probability of survival after transplantation in standard-risk and higher-aged patients. Unrelated transplantation in CR1 improves the long-term survival probability in patients who lack an HLA-matched sibling. However, recent improvements in treatment strategies may change this result.

Effect of related donor availability on outcome of AML in the context of related and unrelated hematopoietic cell transplantation.

Although allogeneic hematopoietic cell transplantation (HCT) from a related donor is effective therapy for younger patients with AML, it remains unknown how the availability of a related donor affects the outcome when unrelated HCT is a treatment option for patients without a related donor. To address this issue, we retrospectively analyzed 605 cytogenetically non-favorable AML patients younger than 50 years for whom a related donor search was performed during first CR (CR1). The 4-year OS was 62% in 253 patients with a related donor and 59% in 352 patients without a related donor (P=0.534). Allogeneic HCT was performed during CR1 in 62% and 41% of patients with and without a related donor, respectively. Among patients transplanted in CR1, the cumulative incidence of non-relapse mortality was significantly higher in patients without a related donor (P=0.022), but there was no difference in post-transplant OS between the groups (P=0.262). These findings show the usefulness of unrelated HCT in younger patients with cytogenetically non-favorable AML who do not have a related donor. The extensive use of unrelated HCT for such patients may minimize the potential disadvantage of lacking a related donor.

Allogeneic hematopoietic stem cell transplantation for adult AML patients with granulocytic sarcoma.

We recently reported that adult acute myeloid leukemia (AML) patients with granulocytic sarcoma (GS) possessed unique clinical features and poor prognosis. However, the optimal therapeutic strategy for this entity has not been established. Therefore, the aim of this study was to assess the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the management of AML with GS. We retrospectively analyzed 503 consecutive adult AML patients (median age, 44 years; range, 15-73 years) who received allo-HSCT. A total of 44 patients (8.7%) had GS before transplantation. Patients with GS achieved comparable survival to those without GS (5-year overall survival (OS), 47% vs 44%, respectively, P=0.621). In patients with GS, excellent outcomes were seen in those that underwent allo-HSCT while in complete remission, whereas nine out of ten patients with GS at the time of transplant experienced a relapse within 6 months after allo-HSCT. Local irradiation for GS prior to allo-HSCT and acute and chronic graft-versus-host disease did not affect survival significantly. Multivariate analysis identified age, disease status and the use of myeloablative conditioning as independent prognostic factors for OS. These data suggest that better control of GS prior to allo-HSCT is crucial to improve the outcome of transplantation for those with GS.

Association of CiaRH with resistance of Streptococcus mutans to antimicrobial peptides in biofilms.

Streptococcus mutans is a cariogenic pathogen in humans. To persist in the oral cavity, S. mutans is resistant against several antibacterial factors derived from the host. In this study, we investigated the mechanism of resistance to cationic antimicrobial peptides (AMPs), which are innate immune factors in humans. Because dltA-D (teichoic acid biosynthesis) was reported to affect the susceptibility to AMPs in other bacterial species, we evaluated the susceptibility of a dltC knockout mutant of S. mutans to the AMPs human beta-defensin-1 (hBD1), hBD2, hBD3 and LL37. The dltC mutant exhibited significantly increased susceptibility to AMPs. Regulation of dltC expression involved CiaRH, a two-component system. Expression of dltC in the wild-type strain was significantly increased in biofilm cells compared with that in planktonic cells, whereas expression was not increased in a ciaRH knockout mutant. In biofilm cells, we found that susceptibility to LL37 was increased in the ciaRH mutant compared with that in the wild type. From these results, it is concluded that Dlt is involved in the susceptibility of S. mutans to AMPs and is regulated by CiaRH in biofilm cells.

Mastication suppresses initial gastric emptying by modulating gastric activity.

Because various mastication-related factors influence gastric activity, the functional relationship between mastication and gastric function has not been fully elucidated. To investigate the influence of mastication on gastric emptying and motility, we conducted a randomized trial to compare the effects of mastication on gastric emptying and gastric myoelectrical activity under conditions that excluded the influences of food comminution, taste, and olfaction. A (13)C-acetate breath test with electrogastrography and electrocardiography was performed in 14 healthy men who ingested a test meal with or without chewing gum. Autonomic nerve activity was evaluated by fluctuation analysis of heart rate. Gastric emptying was significantly delayed in the 'ingestion with mastication' group. Gastric myoelectrical activity was significantly suppressed during mastication and increased gradually in the post-mastication phase. A decrease in the high-frequency power of heart rate variability was observed coincidentally with gastric myoelectrical activity suppression. These findings suggest that initial gastric emptying is suppressed by mastication, and that the suppression is caused by mastication-induced inhibition of gastric activity (UMIN Clinical Trial Registration no. UMIN000005351).

Influence of experimental esophageal acidification on sleep bruxism: a randomized trial.

UNLABELLED: The aim of this cross-over, randomized, single-blinded trial was to examine whether intra-esophageal acidification induces sleep bruxism (SB). Polysomnography with electromyogram (EMG) of masseter muscle, audio-video recording, and esophageal pH monitoring were performed in a sleep laboratory. Twelve healthy adult males without SB participated. Intra-esophageal infusions of 5-mL acidic solution (0.1 N HCl) or saline were administered. The frequencies of EMG bursts, rhythmic masticatory muscle activity (RMMA) episodes, grinding noise, and the RMMA/microarousal ratio were significantly higher in the 20-minute period after acidic infusion than after saline infusion. RMMA episodes including SB were induced by esophageal acidification. This trial is registered with the UMIN Clinical Trials Registry, UMIN000002923. ABBREVIATIONS: ASDA, American Sleep Disorders Association; EMG, electromyogram; GER, gastroesophageal reflux; LES, lower esophageal sphincter; NREM, non-rapid eye movement; REM, rapid eye movement; RMMA, rhythmic masticatory muscle activity; SB, sleep bruxism; SD, standard deviation; UES, upper esophageal sphincter.

A decision analysis of allogeneic hematopoietic stem cell transplantation in adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia in first remission who have an HLA-matched sibling donor.

Clinical studies using genetic randomization cannot accurately answer whether adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia (ALL) who have a human leukocyte antigen (HLA)-matched sibling should undergo allogeneic hematopoietic stem cell transplantation (HSCT) or chemotherapy in first remission, as, in these studies, patients without a sibling donor undergo alternative donor transplantation or chemotherapy alone after a relapse. Therefore, we performed a decision analysis to identify the optimal strategy in this setting. Transition probabilities and utilities were estimated from prospective studies of the Japan Adult Leukemia Study Group, the database of the Japan Society for Hematopoietic Cell Transplantation and the literature. The primary outcome measure was the 10-year survival probability with or without quality of life (QOL) adjustments. Subgroup analyses were performed according to risk stratification on the basis of white blood cell count and cytogenetics, and according to age stratification. In analyses without QOL adjustments, allogeneic HSCT in first remission was superior in the whole population (48.3 vs 32.6%) and in all subgroups. With QOL adjustments, a similar tendency was conserved (44.9 vs 31.7% in the whole population). To improve the probability of long-term survival, allogeneic HSCT in first remission is recommended for patients who have an HLA-matched sibling.