Use of modified barium swallow study to measure posterior airway space in obstructive sleep apnea

Conclusion Measurement of the posterior airway space (PAS) using modified barium swallow (MBS) appears to correlate well with CT imaging. This data suggests MBS may be a low-cost alternative imaging modality to assess obstructive sleep apnea patients. Objectives Obstructive sleep apnea research has focused on imaging modalities that supplement polysomnography in evaluation of potential sites of airway obstruction. While several techniques have been used to assess the PAS, many incur significant costs and risks to the patient. This study proposes use of MBS as a simple modality to measure PAS. Advantages include its simplicity, lower radiation, and dynamic tongue base visualization, which may help predict surgical outcomes. It is hypothesized that cephalometric measurements obtained using MBS will correlate well with CT. Methods Thirty-six adult patients who underwent both CT imaging and MBS for head and neck cancer were included. Cephalometric measurements of the PAS were obtained using each imaging modality. Statistical analysis focused on correlating measurements taken using CT and MBS. Results The average PAS measurements were 12.53?±?1.81?mm and 12.80?±?1.75?mm by MBS and CT imaging, respectively. In comparing the two modalities, Pearson correlation between CT and MBS measurements revealed significant positive correlations between r?=?0.769 and 0.937.     

Morphometry of the respiratory tract: avoiding the sampling, size, orientation, and reference traps

The extrapolation to humans of studies of infectious or toxic agents injurious to the respiratory system using animal models assumes comparability in the structure and function of animal models and humans. Measurement of conducting airways and parenchyma yields quantitative data for parameters like volume, surface area, length, cell number and cell size. Over the past few decades, there has been an evolution of rigorous uniform sampling designs of stereology that ensure unbiased estimates of number, length, surface area, and volume. This approach has been termed 'design-based' stereology because of the reliance on sampling design rather than geometric model-based stereology that makes assumptions. The aim of this paper is to define new design-based stereological approaches for the direct estimation of anatomical structures and epithelial, interstitial and endothelial cells of specific regions of the lung independent of the sampling, size, orientation and reference traps. An example is provided using wildtype and transgenic mice expressing transforming growth factor-alpha to show the importance of the reference trap in stereologic estimates of postnatal lung growth.     

Mitochondrial genome sequences and comparative genomics of <Emphasis Type="Italic">Phytophthora ramorum</Emphasis> and <Emphasis Type="Italic">P. sojae</Emphasis>

The sequences of the mitochondrial genomes of the oomycetes Phytophthora ramorum and P. sojae were determined during the course of complete nuclear genome sequencing (Tyler et al., Science, 313:1261,2006). Both mitochondrial genomes are circular mapping, with sizes of 39,314 bp for P. ramorum and 42,977 bp for P. sojae. Each contains a total of 37 recognizable protein-encoding genes, 26 or 25 tRNAs (P. ramorum and P. sojae, respectively) specifying 19 amino acids, six more open reading frames (ORFs) that are conserved, presumably due to functional constraint, across Phytophthora species (P. sojae, P. ramorum, and P. infestans), six ORFs that are unique for P. sojae and one that is unique for P. ramorum. Non-coding regions comprise about 11.5 and 18.4% of the genomes of P. ramorum and P. sojae, respectively. Relative to P. sojae, there is an inverted repeat of 1,150 bp in P. ramorum that includes an unassigned unique ORF, a tRNA gene, and adjacent non-coding sequences, but otherwise the gene order in both species is identical. Comparisons of these genomes with published sequences of the P. infestans mitochondrial genome reveals a number of similarities, but the gene order in P. infestans differed in two adjacent locations due to inversions and specific regions of the genomes exhibited greater divergence than others. For example, the breakpoints for the inversions observed in P. infestans corresponded to regions of high sequence divergence in comparisons between P. ramorum and P. sojae and the location of a hypervariable microsatellite sequence (eight repeats of 24 bp) in the P. sojae genome corresponds to a site of major length variation in P. infestans. Although the overwhelming majority of each genome is conserved (81–92%), there are a number of genes that evolve more rapidly than others. Some of these rapidly evolving genes appear specific to Phytophthora, arose recently, and future evaluation of their function and the effects of their loss could prove fruitful for understanding the phylogeny of these devastating plant pathogens. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Two-dimensional mapping of the central and parafoveal visual field to human visual cortex

Primate visual cortex contains a set of maps of visual space. These maps are fundamental to early visual processing, yet their form is not fully understood in humans. This is especially true for the central and most important part of the visual field--the fovea. We used functional magnetic resonance imaging (fMRI) to measure the mapping geometry of human V1 and V2 down to 0.5 degrees of eccentricity. By applying automated atlas fitting procedures to parametrize and average retinotopic measurements of eight brains, we provide a reference standard for the two-dimensional geometry of human early visual cortex of unprecedented precision and analyze this high-quality mean dataset with respect to the 2-dimensional cortical magnification morphometry. The analysis indicates that 1) area V1 has meridional isotropy in areal projection: equal areas of visual space are mapped to equal areas of cortex at any given eccentricity. 2) V1 has a systematic pattern of local anisotropies: cortical magnification varies between isopolar and isoeccentricity lines, and 3) the shape of V1 deviates systematically from the complex-log model, the fit of which is particularly poor close to the fovea. We therefore propose that human V1 be fitted by models based on an equal-area principle of its two-dimensional magnification. 4) V2 is elongated by a factor of 2 in eccentricity direction relative to V1 and has significantly more local anisotropy. We propose that V2 has systematic intrinsic curvature, but V1 is intrinsically flat.     

A Prospective Cohort Study of the Impact of Return-to-Work Coordinators in Getting Injured Workers Back on the Job

Purpose To assess the impact of workplace-based return-to-work (RTW) Coordinators’ interpersonal and functional activities on RTW outcomes. Methods Multivariable logistic regression analyses of cross-sectional and longitudinal survey responses of 632 injured workers with at least 10 days of work absence in Victoria, Australia, adjusting for demographic and other workplace factors. Outcome was being back at work for at least 1 month, measured at both baseline and 6 month follow-up survey. Participant responses to stressfulness of Coordinator interactions were dichotomised into good and poor and evaluated as a proxy for Coordinators’ interpersonal activities, while having a RTW plan was evaluated as a proxy for functional activities. Results At baseline, RTW plans doubled the odds of RTW (OR 2.02; 95% CI 1.40–2.90) and attenuated the impact of good Coordinator interactions (1.14; 0.77–1.70). At 6-month follow-up, the opposite was observed: good interactions nearly doubled odds of RTW (1.90; 1.22–2.95) while RTW plans were non-significant (1.02; 0.68–1.54). Conclusions Differences between when the two Coordinator activities were effective may be due to the nature of claimants who RTW in each survey period. Length of shorter-duration claims are influenced by injury related factors, while psychosocial factors tend to be more important for longer-duration claims. Such factors may determine whether a claimant is more likely to respond to Coordinators’ functional or interpersonal activities. The findings have important implications for increasing Coordinator effectiveness.     

Global Forum of Cancer Surgeons: Cancer Surgery During the COVID-19 Pandemic: Impact and Lessons Learned

Annals of Surgical Oncology - The purpose of this article is to summarize the opinions of the surgical oncology leaders from the Global Forum of Cancer Surgeons (GFCS) about the global impact of...     

Propranolol Promotes Bone Formation and Limits Resorption Through Novel Mechanisms During Anabolic Parathyroid Hormone Treatment in Female C57BL/6J Mice

Although the nonselective β-blocker, propranolol, improves bone density with parathyroid hormone (PTH) treatment in mice, the mechanism of this effect is unclear. To address this, we used a combination of in vitro and in vivo approaches to address how propranolol influences bone remodeling in the context of PTH treatment. In female C57BL/6J mice, intermittent PTH and propranolol administration had complementary effects in the trabecular bone of the distal femur and fifth lumbar vertebra (L₅), with combination treatment achieving microarchitectural parameters beyond that of PTH alone. Combined treatment improved the serum bone formation marker, procollagen type 1 N propeptide (P1NP), but did not impact other histomorphometric parameters relating to osteoblast function at the L₅. In vitro, propranolol amplified the acute, PTH-induced, intracellular calcium signal in osteoblast-like cells. The most striking finding, however, was suppression of PTH-induced bone resorption. Despite this, PTH-induced receptor activator of nuclear factor κ-B ligand (RANKL) mRNA and protein levels were unaltered by propranolol, which led us to hypothesize that propranolol could act directly on osteoclasts. Using in situ methods, we found Adrb2 expression in osteoclasts in vivo, suggesting β-blockers may directly impact osteoclasts. Consistent with this, we found propranolol directly suppresses osteoclast differentiation in vitro. Taken together, this work suggests a strong anti-osteoclastic effect of nonselective β-blockers in vivo, indicating that combining propranolol with PTH could be beneficial to patients with extremely low bone density. © 2022 American Society for Bone and Mineral Research (ASBMR).