Association of sleep‐disordered breathing with decreased cognitive function among patients with dementia

Sleep is known to be essential for proper cognitive functioning. Sleep disturbance, especially respiratory disturbance during sleep, is a risk factor for the development of dementia. However, it is not known whether hypopnoea during sleep is related to severity of cognitive function in patients already diagnosed with dementia. Considering the high prevalence of sleep problems in aged people, it is important to determine if hypopnoea during sleep contributes to dementia. In addition, it would be desirable to develop a feasible method for objectively evaluating sleep in patients with dementia. For this purpose, a simple sleep recorder that employs single or dual bioparameter recording, which is defined as a type‐4 portable monitor, is suitable. In this study, a type‐4 sleep recorder was used to evaluate respiratory function during sleep in 111 patients with dementia, and data suggesting a possible relationship with cognitive function levels were examined. Multivariate logistic regression was used to investigate the association of severity of dementia with sleep‐disordered breathing, age, diabetes, dyslipidaemia and hypertension. It was found that the respiratory disturbance index was associated with severity of cognitive dysfunction in our subjects. Furthermore, patients younger than 80 years were more susceptible to lower cognitive function associated with sleep‐disordered breathing than patients 80 years old or over, because an increase in the respiratory disturbance index was associated with deteriorated cognitive function only in the former age group. These results suggest that proper treatment of sleep apnea is important for the preservation of cognitive function, especially in patients with early‐stage dementia.     

Class II high angle case for which titanium screws were added after mandibular posterior rotation

In skeletal Class II patients with a high mandibular plane angle, it is well known that posterior rotation of the mandible often occurs during treatment using a preadjusted edgewise appliance. In this case, posterior rotation of the mandible with increased overjet occurred after the buccal inclination of the mandibular 2nd molars. This case report describes a Class II high angle case for which titanium screws were added as an absolute anchorage to improve the posterior rotation of the mandible. To correct the posterior rotation of the mandible, mandibular molars were intruded and the mandibular arch was mesially moved using titanium screws. The treatment results show that titanium screws were useful for improving the posterior rotation of the mandible during treatment using a preadjusted edgewise appliance.     

Clinicopathological Differences between Proximal and Distal pT3 Colon Cancer and the Clinical Significance of the Depth of Cancer Invasion beyond the Muscularis Propria

Background/Aims: To investigate differences in clinicopathological features between proximal and distal pT3 colon cancers and to determine whether the depth of the cancer invasion beyond the muscularis propria (DBM) serves as an objective indicator of the depth of tumor invasion in proximal colon cancer and in distal colon cancer. Methodology: A total of 207 patients who underwent surgery for proximal and distal pT3 colon cancer between 1996 and 2001 were included in the analysis. Results: No differences were noted between proximal and distal cancers in lymph node metastasis, distant metastasis, lymphatic/venous invasion, histological type and curability of surgical resection, although proximal cancer patients were significantly older. High-grade malignancy appeared to be more commonly noted in the proximal colon cancer cases but there was no significant difference in prognosis between proximal and distal cancer patients. Conclusions: Regarding the correlation between DBM and prognosis, there was a significant decrease in the 5-year survival rate in patients with proximal lesions of DBM 3000μm or more, and patients with distal lesions of DBM 5000μm or more. DBM is thus an objective indicator of depth of tumor invasion for both proximal and distal lesions, a prognostic factor and a guide to determining whether postoperative adjuvant chemotherapy is indicated for pT3 colon cancer cases.     

Localized Potentiation of Sleep Slow-Wave Activity Induced by Prefrontal Repetitive Transcranial Magnetic Stimulation in Patients with a Major Depressive Episode

BackgroundThe effects of repetitive transcranial magnetic stimulation (rTMS) on sleep structure in major depression are currently unknown.ObjectiveTo determine the effects of prefrontal rTMS on sleep electroencephalography (EEG) in major depression.MethodsIn this open-label pilot study, twelve male patients with relatively mild depression, who had been medication-resistant, underwent 10 daily rTMS sessions over the left dorsolateral prefrontal cortex (DLPFC). Polysomnographic (PSG) data were recorded over four nights: Adaptation, Baseline, Post-1 (after the fifth rTMS session), and Post-2 (after the tenth rTMS session). Discrete Fourier Transform (DFT) band power analyses were performed to quantify delta and sigma band activities during Stages II–IV, and determine time courses of these activities between Baseline and Post-1 (first five sessions) and between Post-1 and Post-2 (last five sessions).ResultsPost-hoc tests based on a three-way ANOVA model indicated significant delta power increase at F3 (t₁₁ = ?2.762, P = 0.018) during the first five sessions; however, sigma power was unchanged. No significant band power changes were observed during the second half. Stages II–IV (percent total sleep time) increased significantly during the first half (t₁₂ = ?2.43, P = 0.033). No other significant changes in sleep parameters or clinical correlations were observed.ConclusionsThe first five sessions of high frequency rTMS to the left DLPFC increase slow-wave activity (SWA) at F3, possibly reflecting locally enhanced synaptic plasticity induced by rTMS. This increased activity was not observed during the last half, possibly due to a homeostatic regulation mechanism intrinsic to SWA.     

Use of a triple antibiotic solution affects the healing process of intentionally delayed replanted teeth in mice

ObjectiveA mixture of ciprofloxacin, metronidazole, and minocycline (3Mix) has been reported to be effective against oral bacteria from carious and endodontic lesions in vitro and in vivo. The objective of this study was to establish an animal model using mice for the application of 3Mix following intentionally delayed tooth replantation and to investigate the effects of 3Mix on the healing process of dental pulp and periodontal tissues.MethodsUpper first molars of ICR mice were extracted, immersed in 3Mix solution at different concentrations for 5–60 min with or without the use of a transfer solution (phosphate buffer solution (PBS)), in addition to transfer solution alone, and subsequently repositioned in the sockets. Immunohistochemistry for nestin and Ki-67, histochemistry for TRAP, and TUNEL assay were performed to assess pulpal healing during days 7–21.ResultsIncreased apoptosis was observed in the PBS group at week 1, followed by cell proliferation at week 2, and tertiary dentin and/or bone-like tissue formation at week 3. In contrast, nestin-positive, newly differentiated, odontoblast-like cells began to align along the pulp–dentin border following the appearance of Ki-67- and TUNEL-positive cells during weeks 1–2 in the 3Mix groups, suggesting that pulpal healing was accelerated. Severe root ankylosis was observed exclusively in the 3Mix groups. Rinsing with PBS before replantation partially rescued the viability of the periodontal ligament, but pulpal healing was delayed.ConclusionsThe application of 3Mix promotes pulpal regeneration of intentionally delayed replanted teeth; however, its use may induce severe damage to periodontal tissues.     

An enrichment medium for increasing a very small number of vibrio parahaemolyticus cells to the detection limit of the loop-mediated isothermal amplification (LAMP) assay

We developed an enrichment medium for use with the loop-mediated isothermal amplification (LAMP) assay (enrichment media + LAMP assay) to quickly increase a very small number of Vibrio parahaemolyticus cells to the detection limit of the assay. Thirty-nine different enrichment media were prepared based on evaluating 12 potential ingredients. From our assessment of the 39 media, enrichment medium #36, which contained 2% sodium chloride, 1% proteose peptone no. 2, 0.1% trehalose, 0.5% α-ketoglutaric acid, 0.25% pyruvic acid, and 0.5% yeast extract (pH 8.6), was found to be most effective at enhancing the proliferation of V. parahaemolyticus during incubation for 3 h at 40oC. We compared the detection limits of the LAMP assay, the enrichment medium #36 + LAMP assay, and the cultivation method using bacterial cell and spiked shrimp sample tests. The detection limits of the LAMP assay, the medium #36 + LAMP assay, and the cultivation method were 10(3), 10(0)-10(-1), and 10(-1) CFU ml(-1), respectively. Enrichment medium #36 promoted a 10(3)- to 10(4)-fold increase in the bacterial population, and the detection limit of the enrichment media + LAMP assay was the same as that of the cultivation method.