No description available.

Two types of ventilation cycle were recorded in unanaesthetised but restrained frogs (Rana pipiens); one concerned with ventilation of the buccal cavity alone (buccal cycle) and the other with lung ventilation (lung cycle). During the former the nares were open and the glottis closed so that only small pressures were generated by the movement of the buccal floor. The onset of a lung ventilation was signalled by activity in the laryngeal dilator muscle and when the glottis opened lung pressure and volume fell while buccal cavity pressure and volume increased. After narial closure the buccal floor was rapidly raised and gas was forced into the lungs from the buccal cavity. At peak pressure in the lungs and buccal cavity the glottis closed and nares opened, the recovery stroke of the pump being passive. Air flow recordings made at the external nares showed two phases of flow during each buccal cycle, while four phases accompanied each lung ventilation cycle. By plotting pressure/volume loops from the buccal pump an analysis was made of the mechanical work performed in one lung ventilation cycle, and the proportion of this work available for lung inflation after various losses against viscous and flow resistive forces in the pump itself; while measurement of the areas of typical sequences of such loops together with respiratory frequency enabled the mechanical work output of the pump to be determined for frogs ranging in size from 24 to 86 grams. Using Hill's classical equation for muscle efficiency, it was possible to estimate mechanical efficiency for single respiratory cycles by calculating the heat of maintenance and heat of shortening of the buccal floor muscles, while simultaneously measuring mechanical work output. Calculated efficiencies of lung ventilation cycles rose as mechanical work performed increased from 7.4% at 0.65 gram.cm/cycle to 19.3% at 2.73 gram.cm/cycle. Diving apnoea in Rana pipiens was induced by the presence of water at the level of the external nares, at which point the nares closed, no water entering the buccal cavity during the dive. Occasional ventilation cycles occurred during the dive in which gas entered the buccal cavity from the lungs, an equal volume then being pumped back into the lungs, but there was no ventilatory exchange with the external medium. Bilateral section of the trigeminal nerves resulted in an abnormal response to submergence, in that water entered the buccal cavity, and in some cases the lungs, while surfacing often did not result in resumption of ventilation. Skin mechanoreceptors in the region of the external narial openings serving the ophthalmic branch of the trigeminal were found to be capable of responding to the minimum stimulus encountered on submersion, movement of a water meniscus across the narial region, while a tonic response to hydrostatic pressure occurred in some preparations. In control experiments cutaneous mechanoreceptors innervated by the spinal nerves were shown to have no response to a water meniscus passing across their receptive fields, suggesting that they possess higher thresholds than the narial receptors. Periods of apnoea could be induced in air in Rana pipiens by bilateral or unilateral stimulation of the cut peripheral ends of the ophthalmic branch of the trigeminal nerve at threshold voltages as low as 30 mv, at a frequency of 200 Hz. Increase in stimulating voltage resulted in longer periods of apnoea before ventilation "broke through", and in these periods the external nares were closed and buccal pressure was held independent of atmospheric pressure. Reduction of the stimulation frequency by a factor of ten after the initiation of apnoea, simulating adaptation of the sensory nerves, proved as effective in maintaining apnoea as continued stimulation at the original frequency. / Science, Faculty of / Zoology, Department of / Graduate

The impact of Chronic Obstructive Pulmonary Disorder is material in the dentistry field which not only centers its efforts on managing the oral health of the afflicted patients, prescribing proper medications, but also on raising awareness mainly through dental hygiene and smoking cessation. This literature review will explore the status and accomplishments of the field of dentistry with regards to battling COPD. The first section of the paper discusses the nature and dynamics of the disease which ranks between the third and fourth most common cause of death in the United States alone. Certain data trends from 1970 until 2002 showed double the death rates caused by the disease, and that exposure to environmental or occupational risk factors (e.g. dust, fumes, etc.) must be seriously considered for the effective management of COPD. The pressure of COPD management is great among dental practitioners who must ensure the safety of patients by providing the most suitable drug regimen and having a well-coordinated dental practice (i.e. with other health practitioners) to avoid exacerbation of the disease which often leads to hospitalization. The latter is often the result of oral devices or materials that are often comprised of small objects which might be swallowed or aspirated into the oropharynx of the patient when proper positioning during dental check-ups is not properly performed. Dentists must also make sure that they are able to gain the patient’s confidence and to avoid patient reluctance during dental care. Numbers and statistics also reveal that an estimated 24 million of the population in the United States is afflicted by COPD, and that is from 2015 alone. It is also prevalent among the male population which has a death rate of 83 per 100,000, while the death rate among women is 57 per 100,000. Immediate treatment of COPD is also emphasized to prevent hospitalization rates from rising, and as far as dental practice is concerned, they are often aware of CODP patients which number approximately 130 out of 2000. Smoking cessation is considered the best preventive measure in COPD management. Educating patients on the real dangers involved with smoking will help encourage them to quit while promoting better oral health. The field of dentistry is constantly responding to the challenges of COPD, and significant breakthroughs have already been achieved due to research efforts on COPD management. Through professional coordination with other fields in the healthcare system, it is with great hope that dental practitioners will contribute more to the alleviation of patient conditions and providing improved quality of life.

AIMS: The aims of this study were to examine the cephalometric and airway measurements on children with Sleep Related Breathing Disorders (SRBD) and without SRBD, and to investigate the impact of maxillary expansion on these measurements. MATERIALS AND METHODS: This observational study utilized data from Boston University Orthodontics Department between 2016 and 2020. Lateral cephalograms, acoustic rhinometry and pharyngometry were obtained at two time points. SRBD was determined by a score of 0.33 or higher according to the Pediatric Sleep Questionnaire. Mann–Whitney U test and Spearman correlation analysis were used to analyze the data. Statistical significance was set at <0.05. RESULTS: A total of 163 children (61 male, 102 female) were included in this study. Certain airway measurements (Ph Volume p=0.02, Rh air resistance p=0.05, Rh minimum resistance p=0.001) were significantly higher in SRBD group compared to non-SRBD group. In the SRBD group there was a significant negative correlation between Ph Min Distance and SNA (p=0.001), SND (p=0.05), mandibular arc (p=0.03), U1-SN (p=0.02), U1-Apo (p=0.03). Positive. correlations were observed between Ph Volume with L1-NB (p=0.05) and Rh Min Distance Left with Pog- NB (p=-0.5), mandibular arc p=0.05, L1-NB (p=0.01), L1-Apo (p=0.01). Rh Min Cross-sectional left was positive correlated with overbite (p=0.03) and Rh Min cross-sectional right with posterior face height (p=0.05). Certain airway measurements and cephalometric measurements were statistically different across expansion and non-expansion groups (RhVolumeRt p=0.003. RhMinCrossSectionalLft p=0.03, RhMindistanceRt p=0.03, RhAirResistanceRt p=0.05, ANB p=0.0058, S-N (mm) p=0.05, U1 - NA (mm) p=0.04, U-Incisor Protrusion p=0.01, nterincisal Angle p=0.01, Upper Lip - S Line p= 0.005, Upper Lip to E-Plane p=0.01 CONCLUSION: Airway measurements and cephalometric measurements differ significantly between SRBD and non-SRBD subjects. Significant correlations were observed between cephalometric measurements and airway measurements in the SRBD children. Maxillary expansion can be a treatment option for improving certain airway and cephalometric values among those with sleep-disordered breathing.

PURPOSE: Previous studies have reported an increased prevalence of ocular diseases in patients with obstructive sleep apnea. The purpose of this study was to examine the link between such ocular diseases as diabetic retinopathy, diabetic macular edema, retinal vein occlusion, central serous chorioretinopathy, age-related macular degeneration, non-arteritic anterior ischemic optic neuropathy, and glaucoma. METHODS: This meta-analysis was conducted through a search using PubMed, Web of Science, Scopus and EMBASE. We identified both retrospective and prospective studies. RESULTS: The final meta-analysis looked at 30 studies and 7 ocular diseases. The data showed a high prevalence of obstructive sleep apnea for diabetic retinopathy and diabetic macular edema patients. Data for glaucoma and non-arteritic anterior ischemic optic neuropathy patients did not show a statistical increase. There was not enough data for retinal vein occlusion, central serous chorioretinopathy and age-related macular degeneration to calculate statistical significance. CONCLUSION: These data suggests that patient populations with diabetic retinopathy and macular edema show increased rates of obstructive sleep apnea. Data suggest that hypoxia is an important part of the pathophysiology of diabetic retinopathy and diabetic macular edema. Because obstructive sleep apnea has been shown to affect the progression of the ocular diseases included in this study, ophthalmologists should screen for the presence of obstructive sleep apnea to better help their patients. / 2021-06-14T00:00:00Z

Sleep apnea impacts one's mental and physical health, and has social consequences which affect all of society. Not only is there is a weak correlation between the severity of sleep apnea and daytime sleepiness as reported on the Epworth Sleepiness Scale (ESS), but there is also a weak correlation between the severity of sleep apnea and prescribed treatment as indicated by 95th percentile pressure on a continuous positive airway pressure (CPAP) machine. This poses difficulty for providers as well as patients throughout screening and treatment. The purpose of this study was to use a biopsychosocial approach to perform a within-subjects analysis in order to quantitatively investigate methods of calculating the severity of sleep apnea. The study included historical data of 75 participants, each diagnosed with obstructive sleep apnea, prescribed Automatic CPAP therapy, and compliant with treatment. The Apnea Hypopnea Index (AHI) was calculated in the current fashion and also while considering the length of a respiratory event, type of respiratory event, and the combination of these two factors. Linear regression was used to determine if there is a significant difference in the relationships between the AHI and the ESS as well as the AHI and the 95th percentile CPAP pressure. Results endorsed neither a strong relationship between the AHIs and the ESS nor a strong relationship between the AHIs and 95th percentile CPAP pressure either. However, the relationships were somewhat stronger when considering the length and type of the respiratory event. Findings support a need for future research to explore these relationships and offer more accurate screening and treatment of individuals with sleep apnea. Ultimately, those with sleep apnea will experience an improvement in mental, physical and social functioning which may positively impact those without sleep apnea.

Indiana University-Purdue University Indianapolis (IUPUI) / Efforts to encourage the medical community to prescribe exercise for disease prevention and management have increased significantly in recent years. In patients with obstructive sleep apnea (OSA), it is encouraging that exercise has been shown to improve sleep efficiency, daytime sleepiness, and disease severity. However, in order to better understand the dose-response relationship between exercise and OSA-related outcomes, accurate and reliable methods for assessing physical activity habits are needed. Purpose: To determine the test-retest reliability and validity of two self-report physical activity questionnaires [Physical Activity Vital Sign (PAVS); International Physical Activity Questionnaire-Short Form (IPAQ-SF)] in an OSA population. Methods: 39 adults with moderate-to-severe OSA wore an accelerometer for seven consecutive days and completed the PAVS and IPAQ-SF (twice within 10 d), along with questionnaires on quality of life, sleepiness, and treatment adherence. Test-retest reliability was determined using intraclass correlation coefficients (ICC). Criterion and construct validity were determined using Pearson (r) and Spearman correlation coefficients (ρ), respectively. Results: PAVS and IPAQ-SF scores were reported as total min/wk of moderate-vigorous physical activity (MVPA). Test-retest reliability for MVPA was excellent for PAVS (ICC = 0.982) and good for IPAQ-SF (ICC = 0.766). MVPA assessed via accelerometry was strongly correlated with PAVS (r = 0.802) and moderately with IPAQ-SF (r = 0.569). Both PAVS and IPAQ-SF were significantly correlated with body mass index (BMI) (ρ = -0.273 and -0.268, respectively), but no other variables. Conclusions: The PAVS and IPAQ-SF are reliable and valid PA questionnaires and may be utilized as a tool for accurately assessing physical activity levels in OSA patients.

No description available.

Solitary extramedullary plasmacytomas are uncommon neoplasms. They occur most frequently in the upper aerodigestive tract and account for 4% of the nonepithelial tumors in this site. The evolution of a plasmacytoma is unsteady and symptoms at presentation have included dystonia, dysphagia, oral pain, cough, and dyspnea on exertion. Plasmaeytoma of the upper aerodigestive tract has not been previously reported as a cause of obstructive sleep apnea.

Indiana University-Purdue University Indianapolis (IUPUI) / The study evaluated the effects of a mandibular repositioning appliance (MRA) in patients with obstructive sleep apnea. The MRA was designed to hold the mandible anteriorly in an attempt to maintain a patent airway. Eleven subjects completed a full-night polysomnogram wherein their normal sleep was recorded half the night without the appliance (control) and the other half with the appliance (test). The sequencing of test and control halves was randomly assigned to avoid bias. After seven subjects were tested with the MRA, the MRA was modified for four additional patients by placing anterior vertical elastics (MRA*) to minimize the opening of the mandible. The skeletal and soft tissue changes with both appliances were analyzed using lateral cephalometric radiographs. The MRA was found to have no significant effect on the obstructive sleep apnea patients as a group. Individual response to the appliance varied from noticeably worse to marked improvement. Subject #2A exhibited the reduction of a moderate-to-severe apnea (Apnea-hypopnea index 55.92) to a clinically acceptable level (Apnea-hypopnea index 9.57) with appliance wear. The treatment was considered successful. Significant cephalometric changes with appliance wear were increased lower facial height, a superiorly positioned hyoid bone relative to the mandibular plane, and a decreased posterior airway space. No cephalometric measurement could accurately predict the outcome of the treatment, and posterior airway space, commonly measured in sleep research, was not reliable. The mandibular repositioning appliance was effective in treating a small percentage of individuals with obstructive sleep apnea. A polysomnogram was needed to quantitatively measure the effectiveness of treatment. Under no circumstance should a subjective evaluation by the patient or the clinician be used to assess treatment results. Further investigation is required to evaluate the long-term effectiveness of this treatment. Periodic follow-up sleep studies are required for any patient treated with this appliance until more long term studies are completed.