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Nasim Montazeri Ghahjaverestan,1,2 Sina Akbarian,1,2 Maziar Hafezi,1,2 Shumit Saha,1,2 Kaiyin Zhu,1 Bojan Gavrilovic,1 Babak Taati,1– 3,* Azadeh Yadollahi1,2,* 1Kite - Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada; 2Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada; 3Computer Science, University of Toronto, Toronto, ON, Canada*These authors contributed equally to this workCorrespondence: Azadeh YadollahiKite - Toronto Rehabilitation Institute, University Health Network, Room 12-106, 550 University Avenue, Toronto, ON M5G 2A2, CanadaTel +1 416 597 3422 Ext 7936Fax +1 416 597 8959Email Azadeh.Yadollahi@uhn.caPurpose: The current gold standard to detect sleep/wakefulness is based on electroencephalogram, which is inconvenient if included in portable sleep screening devices. Therefore, a challenge in the portable devices is sleeping time estimation. Without sleeping time, sleep parameters such as apnea/hypopnea index (AHI), an index for quantifying sleep apnea severity, can be underestimated. Recent studies have used tracheal sounds and movements for sleep screening and calculating AHI without considering sleeping time. In this study, we investigated the detection of sleep/wakefulness states and estimation of sleep parameters using tracheal sounds and movements.Materials and Methods: Participants with suspected sleep apnea who were referred for sleep screening were included in this study. Simultaneously with polysomnography, tracheal sounds and movements were recorded with a small wearable device, called the Patch, attached over the trachea. Each 30-second epoch of tracheal data was scored as sleep or wakefulness using an automatic classification algorithm. The performance of the algorithm was compared to the sleep/wakefulness scored blindly based on the polysomnography.Results: Eighty-eight subjects were included in this study. The accuracy of sleep/wakefulness detection was 82.3± 8.66% with a sensitivity of 87.8± 10.8 % (sleep), specificity of 71.4± 18.5% (awake), F1 of 88.1± 9.3% and Cohen’s kappa of 0.54. The correlations between the estimated and polysomnography-based measures for total sleep time and sleep efficiency were 0.78 (p< 0.001) and 0.70 (p< 0.001), respectively.Conclusion: Sleep/wakefulness periods can be detected using tracheal sound and movements. The results of this study combined with our previous studies on screening sleep apnea with tracheal sounds provide strong evidence that respiratory sounds analysis can be used to develop robust, convenient and cost-effective portable devices for sleep apnea monitoring.Keywords: sleep apnea, apnea/hypopnea index, principal component analysis, classification, imbalanced data

Statement of Problem: Hemostatic agents may affect the micro-leakage of different adhesive systems. Also, chlorhexidine has shown positive effects on micro-leakage. However, their interaction effect has not been reported yet. Objectives: To evaluate the effect of contamination with a hemostatic agent on micro- leakage of total- and self-etching adhesive systems and the effect of chlorhexidine application after the removal of the hemostatic agent. Materials and Methods: Standardized Class V cavity was prepared on each of the sixty caries free premolars at the cemento-enamel junction, with the occlusal margin located in enamel and the gingival margin in dentin. Then, the specimens were randomly divided into 6 groups (n = 10) according to hemostatic agent (H) contamination, chlorhexidine (CHX) application, and the type of adhesive systems (Adper Single Bond and Clearfil SE Bond) used. After filling the cavities with resin composite, the root apices were sealed with utility wax. Furthermore, all the surfaces, except for the restorations and 1mm from the margins, were covered with two layers of nail varnish. The teeth were immersed in a 0.5% basic fuschin dye for 24 hours, rinsed, blot-dried and sectioned longitudinally through the center of the restorations bucco- lingualy. The sections were examined using a stereomicroscope and the extension of dye penetration was analyzed according to a non-parametric scale from 0 to 3. Statistical analysis was performed using Kruskal-Wallis test and Mann-Whitney U-test. Results: While ASB group showed no micro-leakage in enamel, none of the groups showed complete elimination of micro-leakage from the dentin. Regarding micro- leakage at enamel, and dentin margins, there was no significant difference between groups 1 and 2, 1 and 3, and 2 and 3 (p > 0.05). A significantly lower micro-leakage at the enamel and dentin margins was observed in group 3, compared to group 6. No significant difference was observed between groups 4 and 5 in enamel (p = 0.35) and dentin (p = 0.34). Group 6 showed significantly higher micro-leakage, compared to group 4 and 5 (p < 0.05). Conclusions: Hemostatic agent contamination had no significant effect on micro- leakage of total- and self-etching adhesive systems. Application of chlorhexidine after the removal of hemostatic agent increased micro-leakage in self-etching adhesives but did not affect when total-etching was used.

Lupus erythematosus (LE) is an autoimmune disease. The mortality rate and causes of death are different in various countries. The present study is done to find out the causes of mortality in the systemic lupus erythematosus (SLE) patients in lupus unit of Rheumatology Research Center and other wards of Shariati Hospital. This study was retrospective according to medical records of patients who were referred to Lupus Unit of Rheumatology Research center, ICU, Gynecology and Nephrology wards of Shariati hospital during 10 years, from 1991 till 2001. Of 2021-recorded patient’s files, 165 (7.8%) deaths were already recorded. 84.8% were female and 15.2% male. The duration of disease was 36±12 months. The mean duration of follow up from entering the study till time of death was 25.9±16.8 months. The causes of mortality were as follows: infection (12.1%), respiratory (8.5%), CNS (13.9%), kidney (3.6%), malignancy (1.2%), unknown (7.8%), active lupus (3%). Infection accompanied with other causes (27.9%) , respiratory with other causes (11.5%), CNS with other causes (5.5%) and renal with other causes (4.8%). Infections are the most common cause of death in SLE Iranian patients, which is compatible with some multicentric studies. But in some previous studies myocardial infarction was reported as the main cause of death.

Epitranscriptomic mechanisms linking tRNA function and the brain proteome to cognition and complex behaviors are not well described. Here, we report bi-directional changes in depression-related behaviors after genetic disruption of neuronal tRNA cytosine methylation, including conditional ablation and transgene-derived overexpression of Nsun2 in the mouse prefrontal cortex (PFC). Neuronal Nsun2-deficiency was associated with a decrease in tRNA m5C levels, resulting in deficits in expression of 70% of tRNAGly isodecoders. Altogether, 1488/5820 proteins changed upon neuronal Nsun2-deficiency, in conjunction with glycine codon-specific defects in translational efficiencies. Loss of Gly-rich proteins critical for glutamatergic neurotransmission was associated with impaired synaptic signaling at PFC pyramidal neurons and defective contextual fear memory. Changes in the neuronal translatome were also associated with a 146% increase in glycine biosynthesis. These findings highlight the methylation sensitivity of glycinergic tRNAs in the adult PFC. Furthermore, they link synaptic plasticity and complex behaviors to epitranscriptomic modifications of cognate tRNAs and the proteomic homeostasis associated with specific amino acids.