Improving the Accuracy of Biologically Effective Dose Estimates, from a Previously Published Study, After Radiosurgery for Acoustic Neuromas.

OBJECTIVE: To recalculate biological effective dose values (BED) for radio-surgical treatments of acoustic neuroma from a previous study. BEDs values were previously overestimated by only using beam-on times in calculations, so excluding the important beam-off-times (when deoxyribonucleic acid repair continues) which contribute to the overall treatment time. Simple BED estimations using a mono-exponential approximation may not always be appropriate but if used should include overall treatment time. METHODS: Time intervals between isocenters were estimated. These were especially important for the Gamma Knife Model 4C cases since manual changes significantly increase overall treatment times. Individual treatment parameters, such as iso-center number, beam-on-time, and beam-off-time, were then used to calculate BED values using a more appropriate bi-exponential model that includes fast and slow components of DNA damage repair over a wider time range. RESULTS: The revised BED estimates differed significantly from previously published values. The overestimates of BED, obtained using beam-on-time only, varied from 0%-40.3%. BED subclasses, each with a BED range of 5 Gy2.47, indicated that revised values were consistently reduced when compared with originally quoted values, especially for 4C compared with Perfexion cases. Furthermore, subdivision of 4C cases by collimator number further emphasized the impact of scheduled gap times on BED. Further analysis demonstrated important limitations of the mono-exponential model. Target volume was a major confounding factor in the interpretation of the results of this study. CONCLUSIONS: BED values should be estimated by including beam-on and beam-off times. Suggestions are provided for more accurate BED estimations in future studies.

Seven-Day Pedometer-Assessed Step Counts and Brain Volume: A Population-Based Observational Study.

BACKGROUND: To investigate the association between step counts and brain volumes (BVs)-global and 6 a priori selected cognition-related regions of interest-in Japanese men aged 40-79 years. METHODS: The authors analyzed data from 680 cognitively intact participants of the Shiga Epidemiological Study of Subclinical Atherosclerosis-a population-based observational study. Using multivariable linear regression, the authors assessed cross-sectional associations between 7-day step counts at baseline (2006-2008) and BVs at follow-up (2012-2015) for age-stratified groups (<60 y and ≥60 y). RESULTS: In the older adults ≥60 years, step counts at baseline (per 1000 steps) were associated with total BV at follow-up (ß = 1.42, P = .022) while adjusted for potential covariates. Regions of interest-based analyses yielded an association of step counts with both prefrontal cortexes (P < .05) in older adults, while the left entorhinal cortex showed marginally significant association (P = .05). No association was observed with hippocampus, parahippocampal, cingulum, and cerebellum. No association was observed in younger adults (<60 y). CONCLUSIONS: The authors found a positive association between 7-day step counts and BVs, including prefrontal cortexes, and left entorhinal cortex in apparently healthy Japanese men.

Properties, Structures, and Physiological Roles of Three Types of Anion Channels Molecularly Identified in the 2010's.

Molecular identification was, at last, successfully accomplished for three types of anion channels that are all implicated in cell volume regulation/dysregulation. LRRC8A plus LRRC8C/D/E, SLCO2A1, and TMEM206 were shown to be the core or pore-forming molecules of the volume-sensitive outwardly rectifying anion channel (VSOR) also called the volume-regulated anion channel (VRAC), the large-conductance maxi-anion channel (Maxi-Cl), and the acid-sensitive outwardly rectifying anion channel (ASOR) also called the proton-activated anion channel (PAC) in 2014, 2017, and 2019, respectively. More recently in 2020 and 2021, we have identified the S100A10-annexin A2 complex and TRPM7 as the regulatory proteins for Maxi-Cl and VSOR/VRAC, respectively. In this review article, we summarize their biophysical and structural properties as well as their physiological roles by comparing with each other on the basis of their molecular insights. We also point out unsolved important issues to be elucidated soon in the future.

The mechanism of volume-related mitral regurgitation from anatomy of mitral valve / 中国胸心血管外科临床杂志

@#Objective    To explore the mechanism of volume-related mitral regurgitation (MR) from the anatomy of mitral valve. Methods    A total of 32 patients with ventricular septal defect (VSD) combined MR meeting inclusion criteria in West China Hospital from September 2018 to November 2019 were enrolled in this study. The direction relative to the cardiac axis: the deviation of the MR bundle along the left atrial wall was eccentric, otherwises it was central. There were 23 patients of VSD and eccentric MR (EMR, a VSD-EMR group), including 10 males and 13 females aged 21 (10, 56) months, and 9 patients of VSD and central MR (CMR, a VSD-CMR group), including 4 males and 5 females aged 26 (12, 87) months. Besides, 9 healthy children were enrolled in a control group, including 4 males and 5 females aged 49 (15, 72) months. All patients underwent transthoracic echocardiography (TTE) examination at 2 weeks before surgery and 6 months after surgery, respectively, The MR degree, end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), antero-posterior diameter (AP), annulus circumference (AC), commissural diameter (CD) were assessed. Results    Before operation, EDV, ESV, SV, AP, AC and CD in the VSD-EMR and VSD-CMR groups were significantly larger or longer than those in the control group (P<0.05); after operation, EDV, ESV, SV, AP and CD decreased compared with those before operation (P<0.05), but there was no significant difference compared with the control group (P>0.05). Compared with the control group, AC was slightly decreased (P<0.05). There was no significant difference in EF between and within groups before and after operation (P>0.05). The improvement rate of MR was 78.9%(15/19) in the VSD-EMR group and 100.0% (9/9) in the VSD-CMR group. Conclusion    After unloading of volume, the valve structure is back to normal except AC. The improvement rate of MR in the VSD-EMR group is lower than that in the VSD-CMR group, which may indicate that the mechanism of VSD-EMR is more complicated.

Impact of Smoking and Alcohol Use on Facial Aging in Women: Results of a Large Multinational, Multiracial, Cross-sectional Survey.

Objective: Data on associations between facial aging and smoking or alcohol consumption are generally derived from small studies, and therefore, vary. The aim of this large multinational study was to determine more accurately which clinical signs of skin- and volume-related facial aging are associated with tobacco and alcohol use in women. Design: This was a subanalysis of a global, cross-sectional, Internet-based survey of self-reported facial aging. Participants: Women aged 18 to 75 years old (n=3,267) from the United States, Australia, Canada, and the United Kingdom who described themselves as white, Asian, black, or Hispanic were included. Measurements: Using a mirror, participants determined their own aging severity on photonumeric rating scales for 11 facial characteristics. Linear regressions were used to assess associations between each feature's severity and smoking status (never vs. current and former smoker); smoking pack years (0 versus 1-10, 11-20, and >20 years); alcohol use (none vs. moderate and heavy); and alcoholic beverage type, after controlling for body mass index, country, age, and race. Results: Smoking was associated with an increased severity of forehead, crow's feet, and glabellar lines; under-eye puffiness; tear-trough hollowing; nasolabial folds; oral commissures; perioral lines; and reduced lip fullness (p≤0.025) but not midface volume loss or visible blood vessels. Heavy alcohol use (≥8 drinks/week) was associated with increased upper facial lines, under-eye puffiness, oral commissures, midface volume loss, and blood vessels (p≤0.042). Conclusion: Smoking and alcohol consumption significantly but differentially impact skin and volume-related facial aging.

Strategies for the Integration of Cough and Swallow to Maintain Airway Protection in Humans.

PURPOSE: Airway protective behaviors, like cough and swallow, deteriorate in many populations suffering from neurologic disorders. While coordination of these behaviors has been investigated in an animal model, it has not been tested in humans. METHODS: We used a novel protocol, adapted from previous work in the cat, to assess cough and swallow independently and their coordination strategies in seven healthy males (26 ± 6 years). Surface electromyograms of the submental complex and external oblique complex, spirometry, and thoracic and abdominal wall kinematics, were used to evaluate the timing of swallow, cough, and breathing as well as lung volume (LV) during these behaviors. RESULTS: Unlike the cat, there was significant variability in the cough-swallow phase preference; however, there was a targeted LV range in which swallow occurred. CONCLUSION: These results give insight into the differences between the cat and human models in airway protective strategies related to the coordination of cough and swallow behaviors, allowing for better understanding of dystussia and dysphagia.

Comparison of self-reported signs of facial ageing among Caucasian women in Australia versus those in the USA, the UK and Canada.

BACKGROUND/OBJECTIVES: Australians are more exposed to higher solar UV radiation levels that accelerate signs of facial ageing than individuals who live in temperate northern countries. The severity and course of self-reported facial ageing among fair-skinned Australian women were compared with those living in Canada, the UK and the USA. METHODS: Women voluntarily recruited into a proprietary opt-in survey panel completed an internet-based questionnaire about their facial ageing. Participants aged 18-75 years compared their features against photonumeric rating scales depicting degrees of severity for forehead, crow's feet and glabellar lines, tear troughs, midface volume loss, nasolabial folds, oral commissures and perioral lines. Data from Caucasian and Asian women with Fitzpatrick skin types I-III were analysed by linear regression for the impact of country (Australia versus Canada, the UK and the USA) on ageing severity for each feature, after controlling for age and race. RESULTS: Among 1472 women, Australians reported higher rates of change and significantly more severe facial lines (P ≤ 0.040) and volume-related features like tear troughs and nasolabial folds (P ≤ 0.03) than women from the other countries. More Australians also reported moderate to severe ageing for all features one to two decades earlier than US women. CONCLUSIONS: Australian women reported more severe signs of facial ageing sooner than other women and volume-related changes up to 20 years earlier than those in the USA, which may suggest that environmental factors also impact volume-related ageing. These findings have implications for managing their facial aesthetic concerns.

Development and validation of a computational finite element model of the rabbit upper airway: simulations of mandibular advancement and tracheal displacement.

The mechanisms leading to upper airway (UA) collapse during sleep are complex and poorly understood. We previously developed an anesthetized rabbit model for studying UA physiology. On the basis of this body of physiological data, we aimed to develop and validate a two-dimensional (2D) computational finite element model (FEM) of the passive rabbit UA and peripharyngeal tissues. Model geometry was reconstructed from a midsagittal computed tomographic image of a representative New Zealand White rabbit, which included major soft (tongue, soft palate, constrictor muscles), cartilaginous (epiglottis, thyroid cartilage), and bony pharyngeal tissues (mandible, hard palate, hyoid bone). Other UA muscles were modeled as linear elastic connections. Initial boundary and contact definitions were defined from anatomy and material properties derived from the literature. Model parameters were optimized to physiological data sets associated with mandibular advancement (MA) and caudal tracheal displacement (TD), including hyoid displacement, which featured with both applied loads. The model was then validated against independent data sets involving combined MA and TD. Model outputs included UA lumen geometry, peripharyngeal tissue displacement, and stress and strain distributions. Simulated MA and TD resulted in UA enlargement and nonuniform increases in tissue displacement, and stress and strain. Model predictions closely agreed with experimental data for individually applied MA, TD, and their combination. We have developed and validated an FEM of the rabbit UA that predicts UA geometry and peripharyngeal tissue mechanical changes associated with interventions known to improve UA patency. The model has the potential to advance our understanding of UA physiology and peripharyngeal tissue mechanics.

Optimizing resources for the surgical care of children: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee consensus statement.

The United States' healthcare system is facing unprecedented pressures: the healthcare cost curve is not sustainable while the bar of standards and expectations for the quality of care continues to rise. Systems committed to the surgical treatment of children will likely require changes and reorganization. Regardless of these mounting pressures, hospitals must remain focused on providing the best possible care to each child at every encounter. Available clinical expertise and hospital resources should be optimized to match the complexity of the treated condition. Although precise criteria are lacking, there is a growing consensus that the optimal combination of clinical experience and hospital resources must be defined, and efforts toward this goal have been supported by the Regents of the American College of Surgeons, the members of the American Pediatric Surgical Association, and the Society for Pediatric Anesthesia (SPA) Board of Directors. The topic of optimizing outcomes and the discussion of the concepts involved have unfortunately become divisive. Our goals, therefore, are 1) to provide a review of the literature that can provide context for the discussion of regionalization, volume, and optimal resources and promote mutual understanding of these important terms, 2) to review the evidence that has been published to date in pediatric surgery associated with regionalization, volume, and resource, 3) to focus on a specific resource (anesthesia), and the association that this may have with outcomes, and 4) to provide a framework for future research and policy efforts.