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In the last decade, cellular forces in three-dimensional hydrogels that mimic the extracellular matrix have been calculated by means of Traction Force Microscopy (TFM). However, characterizing the accuracy limits of a traction recovery method is critical to avoid obscuring physiological information due to traction recovery errors. So far, 3D TFM algorithms have only been validated using simplified cell geometries, bypassing image processing steps or arbitrarily simulating focal adhesions. Moreover, it is still uncertain which of the two common traction recovery methods, i.e., forward and inverse, is more robust against the inherent challenges of 3D TFM. In this work, we established an advanced in silico validation framework that is applicable to any 3D TFM experimental setup and that can be used to correctly couple the experimental and computational aspects of 3D TFM. Advancements relate to the simultaneous incorporation of complex cell geometries, simulation of microscopy images of varying bead densities and different focal adhesion sizes and distributions. By measuring the traction recovery error with respect to ground truth solutions, we found that while highest traction recovery errors occur for cases with sparse and small focal adhesions, our implementation of the inverse method improves two-fold the accuracy with respect to the forward method (average error of 23% vs. 50%). This advantage was further supported by recovering cellular tractions around angiogenic sprouts in an in vitro model of angiogenesis. The inverse method recovered higher traction peaks and a clearer pulling pattern at the sprout protrusion tips than the forward method. STATEMENT OF SIGNIFICANCE: Biomaterial performance is often studied by quantifying cell-matrix mechanical interactions by means of Traction Force Microscopy (TFM). However, 3D TFM algorithms are often validated in simplified scenarios, which do not allow to fully assess errors that could obscure physiological information. Here, we established an advanced in silico validation framework that mimics real TFM experimental conditions and that characterizes the expected errors of a 3D TFM workflow. We apply this framework to demonstrate the enhanced accuracy of a novel inverse traction recovery method that is illustrated in the context of an in vitro model of sprouting angiogenesis. Together, our study shows the importance of a proper traction recovery method to minimise errors and the need for an advanced framework to assess those errors.

ImportanceHypertension contributes to more than 1.6 million deaths annually in India, with many individuals being unaware they have the condition or receiving inadequate treatment. Policy initiatives to strengthen disease detection and management through primary care services in India are not currently informed by population preferences.ObjectiveTo quantify population preferences for attributes of public primary care services for hypertension.Design, Setting, and ParticipantsThis cross-sectional study involved administration of a household survey to a population-based sample of adults with hypertension in the Bengaluru Nagara district (Bengaluru City; urban setting) and the Kolar district (rural setting) in the state of Karnataka, India, from June 22 to July 27, 2021. A discrete choice experiment was designed in which participants selected preferred primary care clinic attributes from hypothetical alternatives. Eligible participants were 30 years or older with a previous diagnosis of hypertension or with measured diastolic blood pressure of 90 mm Hg or higher or systolic blood pressure of 140 mm Hg or higher. A total of 1422 of 1927 individuals (73.8%) consented to receive initial screening, and 1150 (80.9%) were eligible for participation, with 1085 (94.3%) of those eligible completing the survey.Main Outcomes and MeasuresRelative preference for health care service attributes and preference class derived from respondents selecting a preferred clinic scenario from 8 sets of hypothetical comparisons based on wait time, staff courtesy, clinician type, carefulness of clinical assessment, and availability of free medication.ResultsAmong 1085 adult respondents with hypertension, the mean (SD) age was 54.4 (11.2) years; 573 participants (52.8%) identified as female, and 918 (84.6%) had a previous diagnosis of hypertension. Overall preferences were for careful clinical assessment and consistent availability of free medication; 3 of 5 latent classes prioritized 1 or both of these attributes, accounting for 85.1% of all respondents. However, the largest class (52.4% of respondents) had weak preferences distributed across all attributes (largest relative utility for careful clinical assessment: β = 0.13; 95% CI, 0.06-0.20; 36.4% preference share). Two small classes had strong preferences; 1 class (5.4% of respondents) prioritized shorter wait time (85.1% preference share; utility, β = −3.04; 95% CI, −4.94 to −1.14); the posterior probability of membership in this class was higher among urban vs rural respondents (mean [SD], 0.09 [0.26] vs 0.02 [0.13]). The other class (9.5% of respondents) prioritized seeing a physician (the term doctor was used in the survey) rather than a nurse (66.2% preference share; utility, β = 4.01; 95% CI, 2.76-5.25); the posterior probability of membership in this class was greater among rural vs urban respondents (mean [SD], 0.17 [0.35] vs 0.02 [0.10]).Conclusions and RelevanceIn this study, stated population preferences suggested that consistent medication availability and quality of clinical assessment should be prioritized in primary care services in Karnataka, India. The heterogeneity observed in population preferences supports considering additional models of care, such as fast-track medication dispensing to reduce wait times in urban settings and physician-led services in rural areas.

During sprouting angiogenesis-the growth of blood vessels from the existing vasculature-endothelial cells (ECs) adopt an elongated invasive form and exert forces at cell-cell and cell-matrix interaction sites. These cell shape changes and cellular tractions require extensive reorganizations of the actomyosin network. However, the respective roles of actin and myosin for endothelial sprouting are not fully elucidated. In this study, we further investigate these roles by treating 2D-migrating and 3D-sprouting ECs with chemical compounds targeting either myosin or actin. These treatments affected the endothelial cytoskeleton drastically and reduced the invasive response in a compound-specific manner; pointing toward a tight control of the actin and myosin activity during sprouting. Clusters in the data further illustrate that endothelial sprout morphology is sensitive to the in vitro model mechanical microenvironment and directs future research toward mechanical substrate guidance as a strategy for promoting engineered tissue vascularization. In summary, our results add to a growing corpus of research highlighting a key role of the cytoskeleton for sprouting angiogenesis. ispartof: CYTOSKELETON vol:77 issue:7 pages:261-276 ispartof: location:United States status: published

Cerebral cavernous malformation (CCM) is a cerebrovascular disease in which stacks of dilated haemorrhagic capillaries form focally in the brain. Whether and how defective mechanotransduction, cellular mosaicism and inflammation interplay to sustain the progression of CCM disease is unknown. Here, we reveal that CCM1- and CCM2-silenced endothelial cells expanded in vitro enter into senescence-associated secretory phenotype (SASP) that they use to invade the extracellular matrix and attract surrounding wild-type endothelial and immune cells. Further, we demonstrate that this SASP is driven by the cytoskeletal, molecular and transcriptomic disorders provoked by ROCK dysfunctions. By this, we propose that CCM2 and ROCK could be parts of a scaffold controlling senescence, bringing new insights into the emerging field of the control of ageing by cellular mechanics. These in vitro findings reconcile the known dysregulated traits of CCM2-deficient endothelial cells into a unique endothelial fate. Based on these in vitro results, we propose that a SASP could link the increased ROCK-dependent cell contractility in CCM2-deficient endothelial cells with microenvironment remodelling and long-range chemo-attraction of endothelial and immune cells.

Article number 100723 We present TFMLAB, a MATLAB software package for 4D (x;y;z;t) Traction Force Microscopy (TFM). While various TFM computational workflows are available in the literature, open-source programs that are easy to use by researchers with limited technical experience and that can analyze 4D in vitro systems do not exist. TFMLAB integrates all the computational steps to compute active cellular forces from confocal microscopy images, including image processing, cell segmentation, image alignment, matrix displacement measurement and force recovery. Moreover, TFMLAB eases usability by means of interactive graphical user interfaces. This work describes the package's functionalities and analyzes its performance on a real TFM case KU Leuven 1S68818N Fonds Wetenschappelijk Onderzoek (FWO) V413019N Fonds Wetenschappelijk Onderzoek (FWO) G085018N Cambridge Conservation Initiative (CCI) 2014TC16RFCB046 Ministerio de Educación, Cultura y Deporte de España CAS17/00096 Ministerio de Economía y Competitividad de España (MINECO) PGC2018-097257-B-C31 Consejo Europeo de Investigación 308223 KU Leuven C14/17/111 Fonds Wetenschappelijk Onderzoek (FWO)/Hercules G0H6316N

This paper utilizes the AcciMap methodology, which was originally developed by Rasmussen in 1997, to systematically investigate the unfortunate aviation accident of Asiana Airlines 214 in San Francisco on July 6, 2013, which resulted in 3 fatalities and the complete loss of the aircraft. This paper captures the associated socio-technical factors into a hierarchical map that correlates the multiple levels of interaction between different categories and key involved players that ultimately resulted in this air crash. In most accidents, including the Asiana Airlines 214, majority of the blame is laid on front-line operators. In this accident, the pilots are blamed for not adhering to standard operating procedures and training guidelines of Asiana Airlines. This is while accidents do not occur as the act of individuals, but rather due to highly responsive and combined processes that involve decisions of several layers of key players. Some of the other significant contributing factors to this accident are lack of overseeing and enforcing regulations; insufficient training provided by the airline company to pilots; no specific requirements by the company to mandate physical/manual, instead of only simulated, line training; cockpit culture; and complex flight control manuals. The AcciMap methodology has been applied to analyze accidents in different industries, such as railroad, offshore drilling and chemical processing. It is, however, noteworthy that due to our knowledge, this methodology has been used for the analysis of very few aviation accidents.

Cerebral Cavernous Malformations (CCM) is a cerebrovascular disease in which stacks of dilated haemorrhagic capillaries form focally in the brain. Whether and how defective mechanotransduction, cellular mosaicism and inflammation interplay to sustain the progression of CCM diseases is unknown. Here, we reveal that CCM1- and CCM2-silenced endothelial cells enter into senescence associated with secretory phenotype (SASP) that they use to invade the extracellular matrix and attract surrounding wild-type endothelial and immune cells. Further, we demonstrate that this SASP is driven by the mechanical and molecular disorders provoked by ROCKs dysfunctions. By this, we identify CCM1/2 and ROCKs as parts of a scaffold controlling senescence, bringing new insights into the emerging field of the control of aging by cellular mechanics. This discovery reconciles the dysregulated traits of CCM1/2-deficient endothelial cells into a unique mechano-dependent endothelial fate that links perturbed mechanics to microenvironment remodelling and long-range activation of endothelial and immune cells.

The Indian health infrastructure is struggling to handle the burgeoning number of people with diabetes. Managing the complications of diabetes in an organized manner through the government health programs is still a distant reality. Here, we describe a program aimed at addressing the problem of diabetic retinopathy in rural areas of Tumkur district in Karnataka. By amalgamating telescreening and our own novel distributive care model, we were able to screen 85% of the registered diabetics in the Government noncommunicable disease clinics and treat 95% of those needing laser therapy. We also describe the importance of using electronic medical records in public health programs which not only increase the efficiency in screening for disease but help in increasing uptake of treatment by tracking defaulters.