Buckling forces and the wavy folds between pleural epithelial cells.

Cell shapes in tissues are affected by the biophysical interaction between cells. Tissue forces can influence specific cell features such as cell geometry and cell surface area. Here, we examined the 2-dimensional shape, size, and perimeter of pleural epithelial cells at various lung volumes. We demonstrated a 1.53-fold increase in 2-dimensional cell surface area and a 1.43-fold increase in cell perimeter at total lung capacity compared to residual lung volume. Consistent with previous results, close inspection of the pleura demonstrated wavy folds between pleural epithelial cells at all lung volumes. To investigate a potential explanation for the wavy folds, we developed a physical simulacrum suggested by D'Arcy Thompson in On Growth and Form. The simulacrum suggested that the wavy folds were the result of redundant cell membranes unable to contract. To test this hypothesis, we developed a numerical simulation to evaluate the impact of an increase in 2-dimensional cell surface area and cell perimeter on the shape of the cell-cell interface. Our simulation demonstrated that an increase in cell perimeter, rather than an increase in 2-dimensional cell surface area, had the most direct impact on the presence of wavy folds. We conclude that wavy folds between pleural epithelial cells reflects buckling forces arising from the excess cell perimeter necessary to accommodate visceral organ expansion.

Evolving topological order in the postnatal visceral pleura.

BACKGROUND: Changes in epithelial cell shape reflects optimal cell packing and the minimization of surface free energy, but also cell-cell interactions, cell proliferation, and cytoskeletal rearrangements. RESULTS: Here, we studied the structure of the rat pleura in the first 15 days after birth. After pleural isolation and image segmentation, the analysis demonstrated a progression of epithelial order from postnatal day 1 (P1) to P15. The cells with the largest surface area and greatest shape variability were observed at P1. In contrast, the cells with the smallest surface area and most shape consistency were observed at P15. A comparison of polygonal cell geometries demonstrated progressive optimization with an increase in the number of hexagons (six-sided) as well as five-sided and seven-sided polygons. Analysis of the epithelial organization with Voronoi tessellations and graphlet motif frequencies demonstrated a developmental path strikingly distinct from mathematical and natural reference paths. Graph Theory analysis of cell connectivity demonstrated a progressive decrease in network heterogeneity and clustering coefficient from P1 to P15. CONCLUSIONS: We conclude that the rat pleura undergoes a striking change in pleural structure from P1 to P15. Further, a geometric and network-based approach can provide a quantitative characterization of these developmental changes.

Risk factors associated with the reported scores on the symptoms severity and functional limitations scales of the Boston Carpal Tunnel Questionnaire: a cross-sectional study.

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. It presents with numbness, paresthesias, and pain. Multiple risk factors are associated with CTS, such as pregnancy, oral contraceptive use, rheumatoid arthritis (RA), and diabetes mellitus (DM). The Boston Carpal Tunnel Questionnaire (BCTQ) is a self-administered questionnaire for assessing the severity of symptoms and functional status of those previously diagnosed with CTS. We aim to identify risk factors associated with higher scores of CTS symptoms severity and functional limitations scales on the BCTQ. Materials and methods: This cross-sectional study was conducted among 366 female participants. The data was mainly collected using the BCTQ. Demographics and risk factors of CTS were added to the study's complete questionnaire; risk factors included RA, DM, hypothyroidism, number of pregnancies, usage of oral contraceptive pills (OCPs), use of smartphones and keyboards. A P value of less than 0.05 was considered statistically significant. Results: Most participants were in their 30s (44%) and housewives. RA, DM, hypothyroidism, and pregnancy were associated with reporting symptoms and functional limitations on BCTQ. OCPs and smartphone use were associated with functional limitations only. Conclusion: Different risk factors are associated with reporting symptoms and functional limitations of CTS on the BCTQ. For example, RA, DM, hypothyroidism, pregnancy, OCPs, and smartphone use have all been found to statistically affect the outcome of the BCTQ in this study. Therefore, clinical confirmation of the CTS diagnosis is required in future studies to ensure that these symptoms and functional limitations are associated with the CTS pathology rather than other risk factors and pathologies for proper targeted treatment plans and outcomes.

Mechanical thrombectomy of symptomatic carotid stenosis with free-floating thrombus in a patient with COVID-19 using transcarotid artery revascularization.

Carotid stenosis with free-floating thrombus is associated with ipsilateral neurologic deficits as a result of cerebrovascular accident or ischemic stroke. Arterial thrombosis and thrombus instability have shown an association with coronavirus disease 2019. Immediate evaluation is essential to assess and prevent thrombus propagation. Traditionally, transfemoral stenting has been performed as minimally invasive intervention. In the present report, we have described the successful use of transcarotid artery revascularization on retrograde flow, aspiration of the thrombus using Penumbra (Penumbra Inc, Alameda, Calif) mechanical thrombectomy, and transcarotid arterial revascularization stenting in a patient with a confirmed case of coronavirus disease 2019.

Epidemiological comparison between the Navarra Major Trauma Registry and the German Trauma Registry (TR-DGU®).

BACKGROUND: International benchmarking can help identify trauma system performance issues and determine the extent to which other countries also experience these. When problems are identified, countries can look to high performers for insight into possible responses. The objective of this study was to compare the treatment and outcome of severely injured patients in Germany and Navarra, Spain. METHODS: Data collected, from 2010 to 2013, in the Navarra Major Trauma Registry (NMTR) and the TraumaRegister DGU® (TR-DGU) were compared. Both registries followed the Utstein Trauma Template (European Core Dataset) for documentation of trauma patients. Adult patients (≥ 16 years) with New Injury Severity Score (NISS) being >15 points were included in this study. Patients who had been admitted to the hospital later than 24 h after the trauma, had been pronounced dead before hospital arrival, or had been injured by hanging, drowning or burns, were excluded. Demographic data, injury data, prehospital data, hospital treatment data, time intervals, and outcome were compared. The expected mortality was calculated using the Revised Injury Severity Classification score II (RISC II). RESULTS: A total of 646 and 43,110 patients were included in the outcome analysis from NMTR and TR-DGU, respectively. The difference between observed and expected mortality was -0.4% (standardized mortality ratio [SMR] 0.97; 95% CI 0.93-1.04) in Germany and 1.6% (SMR 1.08; 95% CI: 1.02-1.14) in Navarra. Differences in the characteristics of trauma patients and trauma systems between the regions were noted. CONCLUSION: The higher observed mortality in Navarra is consistent with the epidemiological characteristics of its population. However, to improve the quality of trauma care in the Navarra trauma system, certain improvements are necessary. There were less young adults with severe injuries in Navarra than in Germany. It is possible to compare data of severely injured patients from different countries if standardized registries are used.

[Scales for predicting outcome after severe trauma]. / Escalas para predicción de resultados tras traumatismo grave.

In this article we review the development of the most-used scales for severe trauma patients over the past 40 years. It is well known that anatomical scales are effective for measuring the severity of injuries and for predicting results. Physiological scales measure the dynamic component after trauma, with a great influence on the prognosis of injured patients. Metabolic scales, both lactate and base deficit, are reflections of tissue hypoperfusion states and therefore shock. The combined scales are used for prediction and comparative assessment of results. The inclusion of factors that influence the prognosis of trauma patients has led to the development of new scales. However, they lack external validation studies for their widespread use. Until these validation studies are conducted caution should be taken with the use of existing scales.

[Influence of prehospital response times in the survival of trauma patients in Navarre]. / Influencia de los tiempos de respuesta prehospitalarios en la supervivencia de los pacientes politraumatizados en Navarra.

The relation between response times and mortality of polytrauma patients in the so-called "golden hour" continues to be a subject of debate. The purpose of this study is to determine the variables related to mortality in these patients and the influence of response times of the Emergency Medical Services in this mortality. To this end, the data in the "Major Trauma of Navarre" Register (retrospective cohort of polytrauma patients attended to by the Navarre Health Service) were analyzed for the four year period between 2010 and 2013. Of the 217 trauma cases available for the analysis, 42 (19%) died. No significant association was found in the multi-variate analysis between the different response times and mortality: arrival at the scene (odds ratio (OR) 1.0; 95% confidence interval (CI) from 0.99 to 1.01), in the scenario (OR 1.00; 95% CI from 0.98 to 1.02) and total time (OR 1.00; 95% CI from 0.99 to 1.01). The variables that influenced mortality are patient age and severity of injuries measured by the prehospital Triage-Revised Trauma Score (T-RTS) and the New Injury Severity Score (NISS). The mortality of polytrauma patients attended to by the emergency system in our region is influenced by age and by the intensity of the aggression suffered, determined by the prehospital T-RTS and by the NISS. The response times of the hospital do not have a significant influence.