Barriers to health care and pregnancy experiences in relation to Black, low-income mothers' perinatal attachment and depression.

The goal of this study was to examine whether barriers to accessing health care and negative pregnancy experiences would predict depressive symptomatology and attachment to their neonates among Black mothers from low-income backgrounds across the perinatal period. We were also interested in examining whether these mothers' engagement in prenatal health practices would buffer against their pregnancy experiences to promote positive postnatal maternal functioning. Participants were 118 Black pregnant women from low-income backgrounds, recruited from WIC and Early Head Start programs. A prenatal assessment between 28 and 40 weeks gestation measured pregnancy experiences and prenatal health practices, and a postnatal assessment about 4 weeks postpartum measured maternal functioning in the form of depressive symptoms and attachment to their neonates. Linear regressions with prenatal health practices included as a moderator suggested that while engaging in positive health practices during pregnancy could potentially buffer against negative pregnancy experiences and prenatal depressive symptoms, it is unlikely to buffer against barriers to accessing health care. These results imply the need to provide support for accessing health care among pregnant women to address disparities in the United States. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Crystalloid Fluid Management of Non-Traumatic Hypotension by New South Wales Ambulance.

INTRODUCTION: Shock is circulatory insufficiency, inadequate oxygen delivery, and cellular hypoxia. Intravenous fluids are essential for shock management. Despite treatment, patients can face persistent shock with ongoing hypotension, contributing to higher mortality. This analysis aims to quantify hypotensive non-traumatic cases in an Australian ambulance service, determine persistent hypotension prevalence, and assess paramedic-administered intravascular fluids' impact on blood pressure changes. METHODS: This study is a retrospective analysis of prehospital fluid resuscitation by New South Wales Ambulance paramedics during 2022. Hypotension is defined as a systolic blood pressure of ≤ 90 mmHg, and persistent hypotension is a systolic blood pressure consistently below 90 mmHg across all observations, with a final blood pressure below 90 mmHg. This study aimed to determine the volume of fluid resuscitation at which a plateau in population-level systolic blood pressure response is observed, by calculating the derivative of the fitted logistic regression model. Moreover, this analysis identified the relative contribution of factors influencing the probability of an attempt at intravenous or intraosseous access using machine learning. RESULTS: Among 796,865 attendances, 23,049 (2.9%) involved non-traumatic patients with hypotension. In total 7,388 (32.1%) of the hypotensive cases resulted in persistent hypotension, of which 3,235 (43.8%) received Hartmann's solution and 1,745 (53.9%) received at least 500 ml of fluids but still had hypotension. The model showed that systolic blood pressure tends to stop increasing after 500-600 milliliters of fluid are given. This suggests that, on average, giving more fluid than this may not raise blood pressure further in a prehospital setting, though individual patient needs can differ. The top four factors from the machine learning shows that as initial respiratory rate goes up, the probability of intravascular access rises. Transport times less than 20 min are associated with a smaller chance of access and younger patients are less likely to receive an attempt. Finally, extremes of systolic blood pressure are more likely to receive access attempts. CONCLUSION: This study found that three percent of non-traumatic attendances have at least one episode of hypotension, and that more than half of these have persistent hypotension. Only 44% of persistently hypotensive received fluids, and half of persistently hypotensive patients stayed hypotensive despite a reasonable volume of prehospital crystalloids.

Quantitation and identification of microplastics accumulation in human placental specimens using pyrolysis gas chromatography mass spectrometry.

The exponential increase in global plastic usage has led to the emergence of nano- and microplastic (NMP) pollution as a pressing environmental issue due to its implications for human and other mammalian health. We have developed methodologies to extract solid materials from human tissue samples by saponification and ultracentrifugation, allowing for highly specific and quantitative analysis of plastics by pyrolysis-gas chromatography and mass spectrometry (Py-GC-MS). As a benchmark, placenta tissue samples were analyzed using fluorescence microscopy and automated particle count, which demonstrated the presence of >1-micron particles and fibers, but not nano-sized plastic particles. Analyses of the samples (n = 10) using attenuated total reflectance-Fourier transform infrared spectroscopy indicated presence of rayon, polystyrene, polyethylene, and unclassified plastic particles. By contrast, among 62 placenta samples, Py-GC-MS revealed that microplastics were present in all participants' placentae, with concentrations ranging widely from 6.5 to 685 µg NMPs per gram of placental tissue, averaging 126.8 ± 147.5 µg/g (mean±SD). Polyethylene was the most prevalent polymer, accounting for 54% of total NMPs and consistently found in nearly all samples (mean 68.8 ± 93.2 µg/g placenta). Polyvinyl chloride and nylon each represented approximately 10% of the NMPs by weight, with the remaining 26% of the composition represented by 9 other polymers. Together, these data demonstrate advancements in the unbiased quantitative resolution of Py-GC-MS applied to the identification and quantification of NMP species at the maternal-fetal interface. This method, paired with clinical metadata, will be pivotal to evaluating potential impacts of NMPs on adverse pregnancy outcomes.

Alternatives to Fish Acute Whole Effluent Toxicity (WET) Testing: Predictability of RTgill-W1 Cells and Fathead Minnow Embryos with Actual Wastewater Samples.

Toxicity assays using fish cells and embryos continue to gain momentum as a more ethical and informative alternative to fish acute toxicity testing. The goal of our study was to test the accuracy of RTgill-W1 cells and the fathead minnow (Pimephales promelas) embryos to predict actual whole effluent toxicity (WET) in the fathead minnow larvae. The three models were compared concurrently using samples of various origins and treatment types. Additionally, the toxicity of reference toxicants (Cd, Cu, NH3-N, 3,4-dichloraniline, and benzalkonium chloride) spiked into a nontoxic wastewater was compared. The toxicity of reference toxicants was tested in isosmotic and hypoosmotic exposure media in RTgill-W1 cells. Of the 28 wastewater samples, 14 induced a toxic response in fish larvae. Embryos predicted 11 of the 14 wastewater samples toxic to the larvae, whereas RTgill-W1 cells predicted the toxicity of all 14 toxic samples to the larvae. In addition, embryos and RTgill-W1 cells predicted toxicity in two and six additional samples, respectively, that were nontoxic to larvae. Exposures in hypoosmotic medium significantly increased sensitivity of RTgill-W1 cells to all reference toxicants, excluding benzalkonium chloride, compared to exposures in isosmotic medium and showed toxicity levels similar to that in larvae. Thus, hypoosmotic exposure medium should be considered for aquatic toxicity testing applications. Overall, both gill cell and embryo models predicted toxicity in the majority of wastewater samples toxic to larvae and demonstrated their applicability for regulatory WET testing.

Characterization of RTgill-W1 cells epithelial development on transwell inserts: Evaluation of osmotic and toxic challenges.

RTgill-W1 cells cannot be directly exposed to freshwater (FW) or seawater (SW) due to osmotic stress. Adjustments of exposure solutions are needed, but these might reduce the bioavailability and toxicity of pollutants. To facilitate cell polarization and allow direct exposure of water samples, cells were cultured on transwell inserts. Monolayer formation was measured by trans-epithelial electrical resistance (TEER) and an apparent permeability (Papp) assay. At 14 days both TEER and Papp indicated the lowest permeability. Cell viability showed that cells can tolerate apical FW with complete medium (L-15/FBS) in the basolateral compartment but SW reduced cell viability. However, when reference toxicants, silver nitrate and sodium dodecyl benzene sulfonate, were added no toxicity was detected. Increased osmolality in the apical side and presence of proteins indicated diffusion from the basolateral to the apical side. Thus, reduced toxicity was likely caused by complexation with media salts and amino acids. A protein and amino acid free exposure medium (L-15/ex) was applied in the basolateral compartment. However, FW exposures with basolateral L-15/ex resulted in reduced cell viability. To reduce osmotic stress, mannitol was added to apical FW maintaining basolateral L-15/ex which improved cell viability and allowed detection of silver toxicity. Finally, RTgill-W1 cells did not show normal tight junction protein (ZO-1) immunocytochemical staining, which fits with the formation of a leaky epithelium. Overall, culturing of RTgill-W1 cells on transwell inserts allowed direct exposure to mannitol FW medium but showed a reduced sensitivity to toxicants. Thus, exposure on flat bottom wells is recommended for routine toxicity testing.

Textbook outcomes for oesophagectomy: A valid composite measure assessment tool for surgical performance in a specialist unit.

INTRODUCTION: In 2017 the Dutch Upper Gastrointestinal Cancer Audit Group proposed a ten-item composite measure for a 'textbook outcome' (TBO) following oesophago-gastric resection. Studies have shown associations between TBO and improved conditional and overall survival. The aim of this study was to evaluate the use of TBO to assess the outcomes from a single specialist unit in a country, with low incidence of disease, allowing comparisons with international specialist centres. MATERIALS AND METHODS: Retrospective analysis of prospectively collected oesophageal cancer surgery data at a single centre, in Australia, between 2013 and 2018. Multivariable logistical regression assessed association between baseline factors and TBO. Post-operative complications were analysed in two separate groups as Clavien-Dindo ≥2 (CD ≥ 2) and Clavien-Dindo ≥3 (CD ≥ 3). Cox-proportional hazards regression analysis determined the association between TBO and survival. RESULTS: 246 patients were analysed, with 50.8% (n = 125) achieving a TBO when complications were defined as CD ≥ 2 and 58.9% (n = 145) when using CD ≥ 3. Patients aged ≥75, and those with a pre-operative respiratory co-morbidity were less likely to achieve a TBO. Overall survival was not influenced by TBO when complications were defined as CD ≥ 2, however it was higher when a TBO was achieved, and complications were defined as CD ≥ 3 (HR 0.54, 95% CI, 0.35 to 0.84, P = 0.007). CONCLUSION: TBO is a multi-parameter metric that allowed benchmarking of the quality of oesophageal cancer surgery in our unit, providing favourable outcomes compared with other published data. There was an association between TBO and improved overall survival when the definition of severe complications was CD ≥ 3.

A review of the characterizations of soft tissues used in human body modeling: Scope, limitations, and the path forward.

Soft tissue material properties are vital to human body models that evaluate interactions between the human body and its environment. Such models evaluate internal stress/strain responses in soft tissues to investigate issues like pressure injuries. Numerous constitutive models and parameters have been used to represent mechanical behavior of soft tissues in biomechanical models under quasi-static loading. However, researchers reported that generic material properties cannot accurately represent specific target populations due to large inter-individual variability. Two challenges that exist are experimental mechanical characterization and constitutive modeling of biological soft tissues and personalization of constitutive parameters using non-invasive, non-destructive bedside testing methods. It is imperative to understand the scope and appropriate applications for reported material properties. Thus, the goal of this paper was to compile studies from which soft tissue material properties were obtained and categorize them by source of tissue samples, methods used to quantify deformation, and material models used to describe tissues. The collected studies displayed wide ranges of material properties, and factors that affected the properties included whether tissue samples were in vivo or ex vivo, from humans or animals, the body region tested, body position during in vivo studies, deformation measurements, and material models used to describe tissues. Because of the factors that affected reported material properties, it is clear that much progress has been made in understanding soft tissue responses to loading, yet there is a need to broaden the scope of reported soft tissue material properties and better match reported properties to appropriate human body models.

Determining frictional properties of pants and cushion cover materials using human soft tissue and a rigid sled and how they affect seated shear forces.

Shear forces on the buttocks while seated are directly linked to friction, yet the frictional properties at the seat interface are unknown. Shear forces are one of the factors related to increase risk of pressure injury formation. The goals of this study included determining coefficients of friction between three cushion covers and two clothing fabrics using a mechanical system as well as human participants and to evaluate the impact of the cushion covers on shear loading on the buttocks while seated. A chair with separate seat pan tilt and back recline movements was built and instrumented with reflective markers and a load cell. A motion capture system and load cell were used to determine the angles of seat pan tilt at which the sled and participants started sliding, as well as shear forces at three recline angles for three cushion covers (vinyl, one-layer nylon, and two-layer nylon). Results showed the vinyl and two-layer nylon cushion covers respectively had the largest and smallest coefficients of friction for both pants materials. The coefficients of friction calculated with the human participants and rigid sled were within 10% of each other, demonstrating similar results. Further, increasing back recline increased shear load on the buttocks, while the two-layer nylon cover reduced shear forces seen on the buttocks. This work furthers the understanding of shear loading on the buttocks, will aid in the protocols for reducing pressure injuries, and suggests that coefficients of friction found using rigid bodies may be applied to deformable bodies.

Diagnostic performance of prospective same-day 18F-FDG PET/MRI and 18F-FDG PET/CT in the staging and response assessment of lymphoma.

BACKGROUND: Accurate staging and response assessment are essential for prognosis and to guide treatment in patients with lymphoma. The aim of this study was to compare the diagnostic performance of FDG PET/MRI versus FDG PET/CT in adult patients with newly diagnosed Hodgkin and Non- Hodgkin lymphoma. METHODS: In this single centre study, 50 patients were prospectively recruited. FDG PET/MRI was performed after staging FDG PET/CT using a single injection of 18F-FDG. Patients were invited to complete same-day FDG PET/MRI with FDG PET/CT at interim and end of treatment response assessments. Performance was assessed using PET/CT as the reference standard for disease site identification, staging, response assessment with Deauville score and concordance in metabolic activity. RESULTS: Staging assessment showed perfect agreement (κ = 1.0, P = 0) between PET/MRI and PET/CT using Ann Arbor staging. There was excellent intermodality correlation with disease site identification at staging (κ = 0.976, P < 0.001) with FDG PET/MRI sensitivity of 96% (95% CI, 94-98%) and specificity of 100% (95% CI, 99-100%). There was good correlation of disease site identification at interim assessment (κ = 0.819, P < 0.001) and excellent correlation at end-of-treatment assessment (κ = 1.0, P < 0.001). Intermodality agreement for Deauville scores was good at interim assessment (κ = 0.808, P < 0.001) and excellent at end-of-treatment assessment (κ = 1.0, P = 0). There was good-excellent concordance in SUV max and mean between modalities across timepoints. Minimum calculated radiation patient effective dose saving was 54% between the two modalities per scan. CONCLUSION: With high concordance in disease site identification, staging and response assessment, PET/MR is a potentially viable alternative to PET/CT in lymphoma that minimises radiation exposure.

Falls on an inpatient rehabilitation spinal injuries unit: the characteristics, circumstances, and consequences.

STUDY DESIGN: Retrospective audit OBJECTIVES: To describe the nature of falls and fallers in a spinal injuries unit (SIU) and identify factors associated with having more than one fall (recurrent fallers) and falls with physical or psychological consequences (consequential falls). SETTING: An Australian inpatient rehabilitation SIU. METHODS: Data were retrospectively extracted from falls incident reports and electronic medical records over a 5-year period. Data were analysed descriptively to summarise participant and fall details. Univariate analyses identified candidate variables for further investigation in a multivariate model for recurrent fallers and consequential falls. RESULTS: Of the 566 persons admitted to the SIU, 132 (23%) participants experienced 207 falls over the 5 years. Of the fallers, 41 (31%) were recurrent fallers experiencing between 2 and 7 falls and 78 (59%) experienced a consequential fall. No significant variables were identified for recurrent fallers. For consequential falls, older age (OR = 1.038, 95% CI, 1.012 to 1.064, p = 0.004) and female gender (OR = 3.581, 95% CI, 1.269 to 10.103, p = 0.016) were significant, as well as falls that occurred on a Sunday (OR = 0.196, 95% CI, 0.061 to 0.630, p = 0.006). Falls while transferring were less likely to be consequential (OR = 4.100, 95% CI, 1.706 to 9.856, p = 0.002). CONCLUSIONS: Nearly one quarter of SIU inpatients experienced a fall with almost a third of those who fell experiencing recurrent falls. Older age, female gender, and Sundays were risk factors for falls with consequence.

Fish Embryo Acute Toxicity Testing and the RTgill-W1 Cell Line as In Vitro Models for Whole-Effluent Toxicity (WET) Testing: An In Vitro/In Vivo Comparison of Chemicals Relevant for WET Testing.

The fathead minnow (Pimephales promelas) fish embryo acute toxicity (FET) test was compared to the fish gill cells (RTgill-W1) in vitro assay and to the fish larvae acute toxicity test to evaluate their sensitivity for whole-effluent toxicity (WET) testing. The toxicity of 12 chemicals relevant for WET testing was compared as proof of principle. The concentrations lethal to 50% of a population (LC50) of embryos were compared to those in fish larvae and to the 50% effect concentration (EC50) in RTgill-W1 cells from previous literature. Along with traditional FET endpoints (coagulation, somite development, tail detachment, and heartbeat), cardiotoxicity was evaluated for WET applicability. Heart rate was measured at LC20 and LC50 values of six subselected chemicals (Cd, Cu, Ni, ammonia, 3,4-dichloraniline, and benzalkonium chloride). In addition, the toxicity of Cd and Ni was evaluated in RTgill-W1 cells exposed in a hypoosmotic medium to evaluate the effect that osmolarity may have on metal toxicity. A significant correlation was found between the FET and larvae LC50 values but not between the RTgill-W1 EC50 and FET LC50 values. Although sensitivity to Ni and Cd was found to increase with hypoosmotic conditions for FET and RTgill-W1 cells, a correlation was only found with removal of Ni from the analysis. Hypoosmotic conditions increased sensitivity with a significant correlation between RTgill-W1 cells and larvae. Cardiotoxicity was shown in three of the five subselected chemicals (Cd, Cu, and 3,4-dichloroaniline). Overall, both in vitro alternative models have shown good predictability of toxicity in fish in vivo for WET chemicals of interest. Environ Toxicol Chem 2022;41:2721-2731. © 2022 SETAC.

Transient changes in mothers' negative emotional reactivity predict changes in the intensity, persistence, and variability of their aversive behavior.

Applying theories of emotion to understanding the regulation of aversive parenting, we used microanalytic observational methods to test whether transient changes in a mother's negative emotional reactivity predict changes over time in key parameters of her moment-to-moment aversive behavior: its intensity, variability, persistence, and connection to difficult child inputs. At multiple times over 2 years, 319 divorcing mothers and their 5- to 12-year-old children were observed as they discussed mutual disagreements. Sequences of talk-turns were recorded and coded for affect and content. Relative to days when a mother was low in negative emotional reactivity, on days when she was high she displayed more intensely aversive behavior, more variable aversiveness, more transitions from average to high or low aversiveness, tendencies to remain aversive longer following spikes in her aversiveness, and difficulty maintaining low aversiveness following drops in her aversiveness. As her negative emotional reactivity increased, she went from being relatively unaffected by children's difficult behavior to being aversively reactive; from ceasing aversive sequences increasingly quickly to ceasing aversive sequences increasingly slowly; from deviating more from her nonreactive low-aversive parenting to deviating less from her reactive high-aversive parenting. Independent of stable individual differences in mothers and children, transient variations in mothers' emotional reactivity may correspond to key moment-to-moment parameters of aversive parenting, even when interactions are relatively noncontentious. The data provide a viable account of how initially transient, context-specific reactivity could initiate moment-to-moment changes in aversive patterns that in some families influence problematic family trajectories over time. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Biomaterial vaccines capturing pathogen-associated molecular patterns protect against bacterial infections and septic shock.

Most bacterial vaccines work for a subset of bacterial strains or require the modification of the antigen or isolation of the pathogen before vaccine development. Here we report injectable biomaterial vaccines that trigger potent humoral and T-cell responses to bacterial antigens by recruiting, reprogramming and releasing dendritic cells. The vaccines are assembled from regulatorily approved products and consist of a scaffold with absorbed granulocyte-macrophage colony-stimulating factor and CpG-rich oligonucleotides incorporating superparamagnetic microbeads coated with the broad-spectrum opsonin Fc-mannose-binding lectin for the magnetic capture of pathogen-associated molecular patterns from inactivated bacterial-cell-wall lysates. The vaccines protect mice against skin infection with methicillin-resistant Staphylococcus aureus, mice and pigs against septic shock from a lethal Escherichia coli challenge and, when loaded with pathogen-associated molecular patterns isolated from infected animals, uninfected animals against a challenge with different E. coli serotypes. The strong immunogenicity and low incidence of adverse events, a modular manufacturing process, and the use of components compatible with current good manufacturing practice could make this vaccine technology suitable for responding to bacterial pandemics and biothreats.

Shifting loads as a result of chair articulations and associated perfusion responses in the context of pressure injuries: An investigation with able-bodied individuals.

Wheelchair users with spinal cord injuries experience pressure injuries at high rates, causing a decrease in quality of life and an increased financial burden. The soft tissue in the buttocks (beneath the ischial tuberosities) and lower back (behind the sacrum) experience large interface pressures over long periods while seated, putting them at high risk of pressure injury development. The goals of this research were to evaluate the ability of an articulating chair design to redistribute pressures on the body and to affect blood perfusion in the buttocks tissue over the ischial tuberosities. Using a unique, custom-designed chair developed for this research, pressure and blood perfusion were obtained for numerous seated positions that included recline, seat pan tilt, and back articulations. Reclining the chair back increased maximum pressures in the buttocks and lower back regions, while it decreased maximum pressures in the upper back and thigh regions. Increasing seat pan tilt, or rotating the anterior edge of the seat pan above the posterior edge, decreased maximum pressures in the buttocks and lower back regions and increased perfusion in the buttocks. Results suggested that using back recline and seat pan tilt together to create a whole-body tilt increased pressures in the back and decreased pressures in the buttocks. Changes in back articulation redistributed pressure in all back regions. Thus, the articulating chair design redistributed pressures in all areas of the body and promoted blood perfusion in the buttocks while seated. Pressure redistribution and perfusion promotion are fundamental to reducing pressure injury risk.

Key Components Related to Pressure Injury Formation: An Initial Investigation Into Pressure Distribution and Blood Perfusion Responses in Wheelchair Users.

Soft tissue around bony prominences in the buttocks and back are high-risk areas prone to the development of pressure injuries. From a clinical perspective, prevention of pressure injuries all together is the ideal situation. Unfortunately, prevalence rates still reach 47% with recurrence rates even higher. The goals of this study were to evaluate the effects of a series of wheelchair movements, some that currently exist in commercial wheelchairs and some new, on interface pressures and perfusion under the buttocks. Twenty-seven chair positions were obtained by varying back recline, seat pan tilt, and articulation of two supports along the back. Although back recline is commonly taught by therapists to be used as a pressure relieving posture, results indicated an increase in pressures under the ischial tuberosities and sacral areas in reclined positions. Articulation of the back supports produced changes in posture moving from an "erect" to "slouched" position. These movements successfully shifted pressures across back regions. Seat pan tilt was effective in shifting pressures off the ischial tuberosity regions. Additionally, in a portion of the participants, seat pan tilt consistently increased perfusion under the ischial tuberosity region. The findings of this research suggest that movements other than back recline should be considered to more effectively alter interface pressures, particularly in high-risk regions like the sacrum and ischial tuberosities.

Tissue matters: In-vivo tissue properties of persons with spinal cord injuries to inform clinical models for pressure ulcer prevention.

The prevalence of pressure ulcers in patients with spinal cord injuries has been estimated to be between 30% and 47%. Individuals with spinal cord injuries sit for a majority of the time, increasing the risk of developing pressure ulcers in the buttocks and thighs due to large internal stresses. Human body models have been developed to study the formation of pressure ulcers, yet a persistent limitation in these models has been the material properties used to represent the soft tissues in the buttocks and thighs. Specifically, soft tissue material property data have not included wheelchair users, such as those with spinal cord injuries. The goals of this research were 1) to determine the in-vivo material properties of soft tissue in the thighs and buttocks of individuals with spinal cord injuries and 2) compare these to properties obtained from able-bodied people. Results indicated that the proximal and middle thigh regions of those who had a spinal cord injury were softer than the same regions as able-bodied individuals, while the distal thigh regions were stiffer. These findings are vital because they indicate that models developed using properties from able-bodied individuals will not produce internal stress or strain magnitudes that represent individuals who have a spinal cord injury. This information suggests that models should obtain material property data sets from their desired population. Human body models must represent the population being studied if they are to inform clinical assessments and make accurate patient predictions.

Applications of the RTgill-W1 Cell Line for Acute Whole-Effluent Toxicity Testing: In Vitro-In Vivo Correlation and Optimization of Exposure Conditions.

The cell line RTgill-W1 was evaluated as an in vitro alternative model for acute fish whole-effluent toxicity (WET) testing. We determined the 50% effective concentration (EC50) that reduces the viability of RTgill-W1 cells for selected toxicants commonly found in effluent samples and correlated those values with the respective 50% lethal concentration (LC50) of freshwater (fathead minnow, Pimephales promelas) and marine (sheepshead minnow, Cyprinodon variegatus) fish species obtained from the literature. Excluding low water-soluble organics and the volatile sodium hypochlorite, significant correlations were measured for metal, metalloids, ammonia, and higher water-soluble organics between in vitro EC50 values and in vivo LC50 values for both species. Typically, toxicity studies with RTgill-W1 cells are conducted by adding salts to the exposure medium, which may affect the bioavailability of toxicants. Osmotic tolerance of RTgill-W1 cells was found between 150 and 450 mOsm/kg, which were set as the hypoosmotic and hyperosmotic limits. A subset of the toxicants were then reexamined in hypoosmotic and hyperosmotic media. Copper toxicity decreased in hyperosmotic medium, and nickel toxicity increased in hypoosmotic and hyperosmotic media. Linear alkylbenzene sulfonate toxicity was not affected by the medium osmolality. Overall, RTgill-W1 cells have shown potential for applications in measuring metal, metalloids, ammonia, and water-soluble organic chemicals in acute WET tests, as well as complementing current toxicity identification and reduction evaluation strategies. In the present study, RTgill-W1 cells have been established as a valid animal alternative for WET testing, and we show that through manipulation of medium osmotic ranges, sensitivity to nickel was enhanced. Environ Toxicol Chem 2021;40:1050-1061. © 2020 SETAC.

Trust in expert versus lay comments in online articles about spanking and car seat safety.

In this study, we experimentally examined parents' perceptions of scientific information about spanking, a controversial topic, and car seat safety, a consensus topic, presented in online news articles. Specifically, we tested whether parents of children ages 2 to 8 years would trust scientific experts (speaking from professional expertise) more than online lay commenters (speaking from personal experience). One hundred and eighty parents across 41 U.S. states were recruited online from Amazon's Mechanical Turk (124 mothers, 56 fathers; 74% White, 9% Black, 8% Latino, 8% Asian, and 1% other or multiple ethnicities). Parents were randomly assigned to read a news article with an expert discussing spanking research that varied by two conditions: The news article contained either anti-spanking lay comments or pro-spanking lay comments. All parents also read a second news article on car seat safety (a consensus topic). Between-condition analyses were used to compare perceptions of the comment conditions, and within-condition analyses were used to compare perceptions of the expert knowledge versus the comments and to compare perceptions of the spanking expert versus the car seat expert. Moderation analyses were used to compare parents' perceptions based on their attitudes toward spanking. Parents with positive attitudes toward spanking recognized pro-spanking comments as opinion, yet still found them more trustworthy than a scientist taking the opposite position. All parents perceived the car seat expert as trustworthy. The results highlight challenges in disseminating information about controversial topics to the public. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The effects of body position on the material properties of soft tissue in the human thigh.

Forty percent of patients with a spinal cord injury acquire a pressure ulcer during rehabilitation, and sixty percent of individuals in elderly care facilities have at least one pressure ulcer upon admittance. A commonality between those populations is the increased amount of time they spend in the seated position. The loading on the buttocks and thighs while in the seated position has been cited as a risk factor for pressure ulcer formation, especially for wheelchair users. Finite element models provide a tool with which to evaluate the internal tissue stresses, but they are reliant upon accurate material properties for the soft tissue. Thus the goals of this research were to determine and compare the material properties of the soft tissue in the thigh and buttock regions in the seated, quadruped (a universally accessible position with the knee and hip articulations similar to the seated position), and prone positions. A custom indenter was designed to collect force and deflection data for the buttocks/proximal thigh, middle thigh, and distal thigh regions of twenty able-bodied individuals. The force and deflection data were converted into stress and stretch data, which were used to obtain parameters from an Ogden material model. Our results indicated that the prone position yielded significantly stiffer tissue properties than in the seated and quadruped positions for both males and females, meaning that position should be taken into account when obtaining material properties that are input into finite element models. Realistic material properties of the soft tissue will lead to better understanding of tissue injury risk.

The impact of acute and chronic resistance exercise on muscle stiffness: a systematic review and meta-analysis.

PURPOSE: Ultrasound is commonly used to measure changes in skeletal muscle morphology in response to both acute and chronic resistance exercise, but little is known on how muscle stiffness changes via ultrasound elastography, which was the purpose of this systematic review and meta-analysis. METHODS: The online data bases of Pubmed, Scopus, and Web of Science were each searched up until February 2020 and the data were analyzed using a random effects model. RESULTS: A total of eight studies (four acute and four chronic) met the inclusion criteria for the quantitative analysis. Following a single bout of exercise, muscle stiffness was increased within the first hour [ES: 1.52 (95% CI 0.14, 2.91); p = 0.031], but was no longer elevated when measured 2 days post-exercise [ES: 0.76 (95% CI - 0.32, 1.83); p = 0.16] or ≥ 7 days post-exercise [ES: 0.20 (95% CI - 0.53, 0.94); p = 0.58]. There was no impact of long-term resistance training on changes in muscle stiffness [ES: - 0.04 (95% CI - 0.24, 0.15); p = 0.653]. CONCLUSION: The primary findings from this meta-analysis indicate that muscle stiffness increases acutely following a single bout of resistance exercise, but does not change long-term with chronic resistance training when measured via ultrasound shear elastography. Given the small number of studies included in this review, future studies may wish to examine changes in muscle stiffness in response to both acute and chronic resistance exercise.