Triplet carbenes with transition-metal substituents.

The extraordinary advances in carbene (R1-C-R2) chemistry have been fuelled by strategies to stabilize the electronic singlet state via π interactions. In contrast, the lack of similarly efficient approaches to obtain authentic triplet carbenes with appreciable lifetimes beyond cryogenic temperatures hampers their exploitation in synthesis and catalysis. Transition-metal substitution represents a potential strategy, but metallocarbenes (M-C-R) usually represent high-lying excited electronic configurations of the well-established carbyne complexes (M≡C-R). Here we report the synthesis and characterization of triplet metallocarbenes (M-C-SiMe3, M = PdII, PtII) that are persistent beyond cryogenic conditions, and their selective reactivity towards carbene C-H insertion and carbonylation. Bond analysis reveals significant stabilization by spin-polarized push-pull interactions along both π-bonding planes, which fundamentally differs from bonding in push-pull singlet carbenes. This bonding model, thus, expands key strategies for stabilizing the open-shell carbene electromers and closes a conceptual gap towards carbyne complexes.

Interspecies Interaction of Bacteria Listeria monocytogenes, Yersinia pseudotuberculosis, and Marine Saprotrophs during Long-Term Culturing in Biofilms.

All bacterial strains studied retained the viability and ability to form both mono- and polycultural biofilms under conditions of long-term culturing in artificial seawater at 6°C and without addition of nutrients. Bacillus sp. and Pseudomonas japonica presumably stimulated the growth and reproduction of the pathogenic bacteria Listeria monocytogenes and Yersinia pseudotuberculosis. Preserved cell viability in a monoculture biofilm for a long period without adding a food source can indicate allolysis. At the same time, in a polycultural biofilm, the metabolites secreted by saprotrophic strains can stimulate the growth of L. monocytogenes and Y. pseudotuberculosis.

Guselkumab Reduces Disease- and Mechanism-Related Biomarkers More Than Adalimumab in Patients with Psoriasis: A VOYAGE 1 Substudy.

Background: Psoriasis is an immune-mediated inflammatory disease characterized by activation of IL-23-driven IL-17-producing T cell and other IL-23 receptor-positive IL-17-producing cell responses. Selective blockade of IL-23p19 with guselkumab was superior to blockade of TNF-α with adalimumab (ADA) in treating moderate-to-severe psoriasis. Objective: Pharmacodynamic responses of guselkumab versus ADA were compared in patients with psoriasis in VOYAGE 1. Design: Inflammatory cytokine serum levels were assessed (n = 118), and lesional and nonlesional skin biopsies were collected (n = 38) in patient subsets at baseline and 4, 24, and 48 weeks after treatment to evaluate pharmacodynamic responses of guselkumab versus those of ADA. Results: Guselkumab provided rapid reductions in serum IL-17A, IL-17F, and IL-22 levels by week 4 versus at baseline, which were maintained through weeks 24 and 48 (P < .001). The magnitude of reduction of IL-17A and IL-22 at week 48 and IL-17F at weeks 4, 24, and 48 were greater with guselkumab than with ADA (all P < .05). In the skin, guselkumab reduced the expression of IL-23/IL-17 pathway-associated and psoriasis-associated genes. Conclusion: These data provide extensive characterization of pharmacodynamic anti-inflammatory responses to IL-23p19 and TNF-α inhibition in human blood and tissue over time with FDA-approved doses of guselkumab and ADA. Trial registration:ClinicalTrials.govClinicalTrials.gov (NCT02207231).

KRAS-driven Tumorigenesis and KRAS-driven Therapy in Pancreatic Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is associated with significant morbidity and mortality and is projected to be the second leading cause of cancer-related deaths by 2030. Mutations in KRAS are found in the vast majority of PDAC cases and plays an important role in the development of the disease. KRAS drives tumor cell proliferation and survival through activating the MAPK pathway to drive cell cycle progression and to lead to MYC-driven cellular programs. Moreover, activated KRAS promotes a pro-tumorigenic microenvironment through forming a desmoplastic stroma and by impairing anti-tumor immunity. Secretion of GM-CSF and recruitment of myeloid-derived suppressor cells and pro-tumorigenic macrophages results in an immunosuppressive environment while secretion of SHH and TGF-beta drive fibroblastic features characteristic of PDAC. Recent development of several small molecules to directly target KRAS mark an important milestone in precision medicine. Many molecules show promise in preclinical models of PDAC and in early phase clinical trials. In this review, we discuss the underlying cell intrinsic and extrinsic roles of KRAS in PDAC tumorigenesis, the pharmacologic development of KRAS inhibition, and therapeutic strategies to target KRAS in PDAC.

Practical Recommendations on Laboratory Monitoring in Patients with Atopic Dermatitis on Oral JAK Inhibitors.

Oral Janus kinase inhibitors (JAKi), a class of advanced targeted systemic therapy, have demonstrated efficacy and safety in the treatment of moderate-to-severe atopic dermatitis (AD). Like other small molecules, oral JAKi have the potential for off-target effects including laboratory-related adverse events (AEs). Product labels for oral JAKi recommend an initial laboratory assessment and follow-up 4-12 weeks later to monitor for potential changes, based on evidence from clinical trials across therapeutic indications for oral JAKi, which may not reflect a population of moderate-to-severe AD patients typically seen in routine clinical practice. To address this gap, a panel of eight dermatologists with clinical and research experience with oral JAKi for the management of AD conducted a targeted review of the literature focused on key laboratory-related AEs associated with oral JAKi in the moderate-to-severe AD population. Based on the synthesis of evidence and informed opinion, a set of best practice statements related to fundamental standards of care and consensus recommendations on laboratory monitoring were suggested, and level of agreement was ascertained using a Likert scale from 0 to 100. There was a high level of agreement on three of the four suggested recommendations related to assessment and monitoring of key laboratory parameters and to dose reduction or switching in response to laboratory changes; there was a lower level of agreement related to the frequency of ongoing laboratory monitoring. Appropriate patient selection and laboratory assessment is an important strategy to mitigate the potential risks associated with oral JAKi when treating AD.

Clinical Characteristics and Outcomes of Extrapulmonary Nontuberculous Mycobacterial Infections in a Tertiary-Care Hospital: A Retrospective Study.

Background/Objectives: The incidence of nontuberculous mycobacterial (NTM) infections has increased globally; however, the clinical manifestations and optimal treatment strategies for extrapulmonary NTM infections remain poorly defined. This study assessed the clinical manifestations and treatment outcomes of extrapulmonary NTM infections. Methods: Data from adult patients with suspected extrapulmonary NTM infections at a tertiary-care hospital from 2009-2022 were categorized into NTM disease and isolation groups. Diagnosis of NTM disease relied on stringent criteria, whereas isolation required NTM isolation without meeting the criteria for infection. Results: Among 75 patients evaluated, 32 (42%) were diagnosed with NTM disease and 43 (57%) with NTM isolation. History of immunosuppressant use within the past 3 months (p = 0.070) and injection (p = 0.001) were more frequent in the disease group. The median interval from symptom onset to evaluation was 106.6 and 20 days in the disease and isolation groups, respectively. The prevalence of positive NTM polymerase chain reaction results (36.4%, p = 0.003) and acid-fast bacillus staining (39.1%, p < 0.001) was significantly higher in the disease group than in the isolation group. Mycobacterium intracellulare (21.9%), M. abscessus (15.6%), M. chelonae (9.4%), and M. fortuitum complex (9.4%) were the most frequently identified species. Of the 27 patients in the disease group who received treatment, 13 improved, four experienced treatment failure, seven were lost to follow-up, and three died during treatment, with one death directly attributable to NTM disease. Conclusions: NTM disease exhibits a spectrum of clinical manifestations. Accurate diagnosis is crucial for initiating effective treatment.

Acute Aortic Dissection: Observational Lessons Learned From 11 000 Patients.

BACKGROUND: Over the past 25 years, diagnosis and therapy for acute aortic dissection (AAD) have evolved. We aimed to study the effects of these iterative changes in care. METHODS: Patients with nontraumatic AAD enrolled in the International Registry of Acute Aortic Dissection (61 centers; 15 countries) were divided into time-based tertiles (groups) from 1996 to 2022. The impact of changes in diagnostics, therapeutic care, and in-hospital and 3-year mortality was assessed. Cochran-Armitage trend and Jonckheere-Terpstra tests were conducted to test for any temporal trend. RESULTS: Each group consisted of 3785 patients (mean age, ≈62 years old; ≈65.5% males); nearly two-thirds had type A AAD. Over time, the rates of hypertension increased from 77.8% to 80.4% (P=0.002), while smoking (34.1% to 30.6%, P=0.033) and atherosclerosis decreased (25.6%-16.6%; P<0.001). Across groups, the percentage of surgical repair of type A AAD increased from 89.1% to 92.5% (P<0.001) and was associated with decreased hospital mortality (from 24.1% in group 1 to 16.7% in group 3; P<0.001). There was no difference in 3-year survival (P=0.296). For type B AAD, stent graft therapy (thoracic endovascular aortic repair) was used more frequently (22.3%-35.9%; P<0.001), with a corresponding decrease in open surgery. Endovascular in-hospital mortality decreased from 9.9% to 6.2% (P=0.003). As seen with the type A AAD cohort, overall 3-year mortality for patients with type B AAD was consistent over time (P=0.084). CONCLUSIONS: Over 25 years, substantial improvements in-hospital survival were associated with a more aggressive surgical approach for patients with type A AAD. Open surgery has been partially supplanted by thoracic endovascular aortic repair for complicated type B AAD, and in-hospital mortality has decreased over the time period studied. Postdischarge survival for up to 3 years was similar over time.

Highly Durable, Stretchable Multielectrode Array for Electro-mechanical Co-stimulation of Cells.

Electro-mechanical co-stimulation of cells can be a useful cue for tissue engineering. However, reliable co-stimulation platforms still have limitations due to low durability of the components and difficulty in optimizing the stimulation parameters. Although various electro-mechanical co-simulation systems have been explored, integrating materials and components with high durability is still limited. To tackle this problem, we designed an electro-mechanical co-stimulation system that facilitates uniaxial cyclic stretching, electrical stimulation, and optical monitoring. This system utilizes a robust and autoclavable stretchable multielectrode array housed within a compact mini-incubator. To illustrate its effectiveness, we conducted experiments that highlighted how electro-mechanical co-stimulation using this system can enhance the maturation of cardiomyocytes derived from human induced pluripotent stem cells. The results showed great potential of our co-stimulation platform as an effective tool for tissue engineering.

Impact of Transition Metal Layer Vacancy on the Structure and Performance of P2 Type Layered Sodium Cathode Material.

This study explores the impact of introducing vacancy in the transition metal layer of rationally designed Na0.6[Ni0.3Ru0.3Mn0.4]O2 (NRM) cathode material. The incorporation of Ru, Ni, and vacancy enhances the structural stability during extensive cycling, increases the operation voltage, and induces a capacity increase while also activating oxygen redox, respectively, in Na0.7[Ni0.2VNi0.1Ru0.3Mn0.4]O2 (V-NRM) compound. Various analytical techniques including transmission electron microscopy, X-ray absorption near edge spectroscopy, operando X-ray diffraction, and operando differential electrochemical mass spectrometry are employed to assess changes in the average oxidation states and structural distortions. The results demonstrate that V-NRM exhibits higher capacity than NRM and maintains a moderate capacity retention of 81% after 100 cycles. Furthermore, the formation of additional lone-pair electrons in the O 2p orbital enables V-NRM to utilize more capacity from the oxygen redox validated by density functional calculation, leading to a widened dominance of the OP4 phase without releasing O2 gas. These findings offer valuable insights for the design of advanced high-capacity cathode materials with improved performance and sustainability in sodium-ion batteries.

Digital outcome measures are associated with brain atrophy in patients with multiple sclerosis.

BACKGROUND: Digital monitoring of people with multiple sclerosis (PwMS) using smartphone-based monitoring tools is a promising method to assess disease activity and progression. OBJECTIVE: To study cross-sectional and longitudinal associations between active and passive digital monitoring parameters and MRI volume measures in PwMS. METHODS: In this prospective study, 92 PwMS were included. Clinical tests [Expanded Disability Status Scale (EDSS), Timed 25 Foot Walk test (T25FW), 9-Hole Peg Test (NHPT), and Symbol Digit Modalities Test (SDMT)] and structural MRI scans were performed at baseline (M0) and 12-month follow-up (M12). Active monitoring included the smartphone-based Symbol Digit Modalities Test (sSDMT) and 2 Minute Walk Test (s2MWT), while passive monitoring was based on smartphone keystroke dynamics (KD). Linear regression analyses were used to determine cross-sectional and longitudinal relations between digital and clinical outcomes and brain volumes, with age, disease duration and sex as covariates. RESULTS: In PwMS, both sSDMT and SDMT were associated with thalamic volumes and lesion volumes. KD were related to brain, ventricular, thalamic and lesion volumes. No relations were found between s2MWT and MRI volumes. NHPT scores were associated with lesion volumes only, while EDSS and T25FW were not related to MRI. No longitudinal associations were found for any of the outcome measures between M0 and M12. CONCLUSION: Our results show clear cross-sectional correlations between digital biomarkers and brain volumes in PwMS, which were not all present for conventional clinical outcomes, supporting the potential added value of digital monitoring tools.

Spondylodiscitis: Understanding pathophysiology, surgical strategies, and postoperative management - A single-center study.

Background: Spondylodiscitis (SD) is an inflammatory condition affecting the intervertebral discs and adjacent structures, often leading to serious complications, including epidural abscesses. This study aimed to differentiate postoperative SD from spontaneous cases caused by osteoporotic defects and associated pathologies, evaluating the frequency of SD in spinal diseases at a single center. Materials and Methods: A retrospective observational study involving 25 patients was conducted, analyzing variations between postoperative revisions in SD patients and spontaneous SD due to concurrent pathology and osteoporotic defects. The effects of postoperative wound healing following transforaminal lumbar interbody fusion and decompressive hemilaminectomy with pedicle screws were also investigated. Ethical guidelines were strictly followed during the study, conducted from January 2023 to September 2023 at Moscow City Clinical Hospital No. 68, Demikhova V.P. Results: Among the 25 patients with spontaneous SD, 15 females and 10 males were included, with only two undergoing surgical revision. Predominant purulent inflammatory foci were observed at specific spinal levels, and demographics revealed prevalent comorbidities such as arterial hypertension (80%) and type 2 diabetes mellitus (60%). Postoperative complications included paravertebral abscesses and wound-related issues. Structural observations indicated vertebral destruction, joint gaps, and localized spinal canal narrowing, revealing complexities in SD cases. Conclusion: Surgical intervention remains crucial for addressing SD-related vertebral complications, while antimicrobial therapy tailored to specific pathogens is pivotal. Concurrent conditions necessitate comprehensive management, often involving cardiological interventions. Postoperatively, a combined approach of conservative therapy and calcium phosphate adjuncts is recommended, especially considering the observed low bone density, aiming to optimize patient recovery and spinal stability.

Empagliflozin attenuates epithelial to mesenchymal transition through senescence in peritoneal dialysis.

BACKGROUND: Epithelial to mesenchymal transition (EMT) is considered as one of the senescence processes; reportedly, anti-senescence therapies effectively reduce EMT. Some models have shown anti-senescence effects with the use of sodium-glucose cotransporter-2 (SGLT2) inhibitor. Therefore, our study investigated the anti-senescence effects of empagliflozin as a SGLT2 inhibitor in a peritoneal fibrosis model and their impact on EMT inhibition. METHODS: For in vitro study, human peritoneal mesothelial cells (HPMCs) were isolated and grown in a 96-well plate. The cell media were exchanged with serum-free M199 medium with D-Glucose, with or without empagliflozin. All animal experiments were carried out in male mice. Mice were randomly classified into three treatment groups based on peritoneal dialysis (PD) or empagliflozin. We evaluated changes in senescence and EMT markers in HPMCs and PD model. RESULTS: HPMCs treated with glucose transformed from cobble stone to spindle shape, resulting in EMT. Empagliflozin attenuated these morphologic changes. Reactive oxygen species production, DNA damage, senescence, and EMT markers were increased by glucose treatment; however, co-treatment with glucose and empagliflozin attenuated these changes. For the mice with PD, an increase in thickness, collagen deposition, staining for senescence or EMT markers of the parietal peritoneum was observed, which however, was attenuated by co-treatment with empagliflozin. p53, p21, and p16 increased in mice with PD compared to that in the control group; however, these changes were decreased by empagliflozin. CONCLUSION: Empagliflozin effectively attenuated glucose-induced EMT in HPMCs through a decrease in senescence. Co-treatment with empagliflozin improved peritoneal thickness and fibrosis in PD.

Improving access to buprenorphine for rural veterans in a learning health care system.

OBJECTIVE: To describe a learning health care system research process designed to increase buprenorphine prescribing for the treatment of opioid use disorder (OUD) in rural primary care settings within U.S. Department of Veterans Affairs (VA) treatment facilities. DATA SOURCES AND STUDY SETTING: Using national administrative data from the VA Corporate Data Warehouse, we identified six rural VA health care systems that had improved their rate of buprenorphine prescribing within primary care from 2015 to 2020 (positive deviants). We conducted qualitative interviews with leaders, clinicians, and staff involved in buprenorphine prescribing within primary care from these sites to inform the design of an implementation strategy. STUDY DESIGN: Qualitative interviews to inform implementation strategy development. DATA COLLECTION/EXTRACTION METHODS: Interviews were audio-recorded, transcribed verbatim, and coded by a primary coder and secondary reviewer. Analysis utilized a mixed inductive/deductive approach. To develop an implementation strategy, we matched clinical needs identified within interviews with resources and strategies participants had utilized to address these needs in their own sites. PRINCIPAL FINDINGS: Interview participants (n = 30) identified key clinical needs and strategies for implementing buprenorphine in rural, primary care settings. Common suggestions included the need for clinical mentorship or a consult service, buprenorphine training, and educational resources. Building upon interview findings and in partnership with a clinical team, we developed an implementation strategy composed of an engaging case-based training, an audit and feedback process, and educational resources (e.g., Buprenorphine Frequently Asked Questions, Rural Care Model Infographic). CONCLUSIONS: We describe a learning health care system research process that leveraged national administrative data, health care provider interviews, and clinical partnership to develop an implementation strategy to encourage buprenorphine prescribing in rural primary care settings.

CRISPR/Cas9-mediated knock-in of a fluorescent reporter into the target locus of interest in human pluripotent stem cells.

The method presented herein is associated with the Lab Resource article titled "Generation of αMHC-EGFP knock-in in human pluripotent stem cell line, SNUe003-A-3, using CRISPR/CAS9-based gene targeting" [1]. The cardiac muscle-specific protein, α-myosin heavy chain (αMHC), is encoded by the human MYH6 gene, which is expressed in both the atria and ventricles during embryonic development and is predominantly expressed in the atria after birth [2]. Herein, the methods used to achieve CRISPR/SpCas9-mediated introduction of an EGFP reporter into αMHC, the target locus in human pluripotent stem cells (hPSCs) for cardiac lineage tracing and clinical cell sorting are described. The CRISPR-Cas9 system enables efficient replacement of the stop codon in the last exon of αMHC with a 2A non-joining peptide (T2A)-EGFP cassette. First, hPSCs are transfected with the donor construct and Cas9/sgRNA plasmids via electroporation and selected with neomycin for approximately 3 weeks. Thereafter, the established cell line exhibits typical characteristics of human embryonic stem cells (hESCs). When these cells differentiate into cardiomyocytes, the expression of EGFP is confirmed using confocal microscopy, flow cytometry analysis, and immunostaining.•The line enables monitoring of cell maturation events during human cardiac development.•The line is a valuable platform for cardiotoxicity tests and drug screening.•This method has already been employed in two original studies, as previously reported for reporter cell line generation using CRISPR/Cas9.

Integration of Germline Genetic Testing Into Routine Clinical Practice for Patients With Pancreatic Adenocarcinoma.

PURPOSE: Germline genetic testing (GT) is recommended for all patients with pancreatic ductal adenocarcinoma (PDAC), but the traditional clinical genetics infrastructure is limited in addressing the unique needs of this population. We describe the integration of point of care (POC) GT into routine clinical practice for all patients with PDAC at an academic medical center. METHODS: We developed a clinical POC workflow that leverages electronic health record (EHR) tools and behavioral nudges to enhance the sustainability and scalability of our previously described research-based POC model. For each of the research and clinical POC cohorts, we calculated the percentage of eligible patients who underwent GT. We used Wilcoxon rank-sum and Pearson's chi-squared tests to compare patients who did and did not undergo GT. We conducted surveys among oncology clinicians to evaluate the acceptability, appropriateness, and feasibility of the clinical POC model. RESULTS: The research POC cohort included 905 patients, of whom 694 (76.7%) underwent GT. The clinical POC cohort included 148 patients, of whom 126 (85.1%) underwent GT. Patients who underwent GT in the research POC cohort were significantly younger (median age, 67.0 v 70.9 years; P = .031) and more likely to be White (82.1% v 68.7%; P < .001) and commercially insured (41.8% v 28.0%; P < .001) compared with those who did not; there were no significant differences between GT groups in the clinical POC cohort. Oncology clinicians found the clinical POC model to be acceptable (mean 4.4/5), appropriate (4.6/5), feasible (4.0/5), and have a positive impact on their patients (4.9/5). CONCLUSION: A clinical POC model leveraging EHR tools and behavioral nudges is acceptable, appropriate, feasible, and associated with a >85% GT rate among patients with PDAC.

Neuronal distribution in colorectal cancer: associations with clinicopathological parameters and survival.

Over the last years, insights in the cancer neuroscience field increased rapidly and a potential role for neurons in colorectal carcinogenesis has been recognized. However, knowledge on the neuronal distribution, subtypes, origin and associations with clinicopathological characteristics in human studies is sparse. In this study, colorectal tumor tissues from the Netherlands Cohort Study on diet and cancer (n=490) and an in-cohort validation population (n=529) were immunohistochemically stained for the pan-neuronal markers neurofilament (NF) and protein gene product 9.5 (PGP9.5) to study the association between neuronal marker expression and clinicopathological characteristics. In addition, tumor and healthy colon tissue were stained for neuronal subtype markers and their immunoreactivity in colorectal cancer (CRC) stroma was analyzed. NF and PGP9.5 positive nerve fibers were found within the tumor stroma and were mostly characterized by the neuronal subtype markers vasoactive intestinal protein (VIP) and neuronal nitric oxide synthase (nNOS), suggesting that inhibitory neurons are the most prominent neuronal subtype in CRC. NF and PGP9.5 protein expression were not consistently associated with tumor stage, sublocation, differentiation grade and median survival. NF immunoreactivity was associated with a worse CRC-specific survival in the study cohort (p=0.025), independent of other prognostic factors (HR=2.31; 95% CI 1.33-4.03; p=0.003), but these results were not observed in the in-cohort validation group. PGP9.5 on the other hand, was associated with a worse CRC-specific survival in the in-cohort validation (p=0.046) but not in the study population. This effect disappeared in multivariate analyses (HR=0.81; 95% CI 0.50-1.32; p=0.393) indicating that this effect was dependent on other prognostic factors. This study demonstrates that the tumor stroma of CRC patients mainly harbors inhibitory neurons and that NF as a single marker is significantly associated with a poorer CRC-specific survival in the study cohort but necessitates future validation.

Ubiquitin: Not just a one-way ticket to the proteasome, but a therapeutic dial to fine-tune the molecular landscape of disease.

Recently, there is a rise in studies that recognize the importance of targeting ubiquitin and related molecular machinery in various therapeutic contexts. Here we briefly discuss the history of ubiquitin, its biological roles in protein degradation and beyond, as well as the current state of ubiquitin-targeting therapeutics across diseases. We conclude that targeting ubiquitin machinery is approaching a renaissance, and tapping its full potential will require embracing a wholistic perspective of ubiquitin's multifaceted roles.

Addressing the need for individual-level exposure monitoring for firefighters using silicone samplers.

BACKGROUND: Firefighters are occupationally exposed to hazardous chemical mixtures. Silicone passive sampling devices capture unique exposures over time with minimal impact to the participant and allow for the analysis of a broad chemical space. OBJECTIVE: Silicone dog tags were worn by firefighters while on- and off-duty to measure individual exposures, identify potential occupational exposures, and assess their relation to occupational variables including fire response frequency, rank, and years as a firefighter. METHODS: Fifty-six firefighters were recruited from two fire departments with relatively high and low call volumes in the Kansas City metropolitan area to wear two different silicone dog tags as passive samplers while on- and off-duty. Each dog tag was worn for a cumulative 30-day exposure period. Extracts of the dog tags were analyzed with gas chromatography, mass spectrometry methods for 43 flame retardants (FRs), 21 volatile organic compounds (VOCs), 42 polychlorinated biphenyls (PCBs), and 63 polycyclic aromatic hydrocarbons (PAHs). RESULTS: Ninety-two total chemicals were detected, with eight chemicals not previously reported in firefighter exposure studies. Based on the magnitude and frequency of increased exposure in on-duty dog tags, relative to paired off-duty dog tags, five PBDEs and sec-butylbenzene were identified as potential occupational exposures; sec-butylbenzene and PBDE 49 have not previously been reported in firefighter exposure studies to the authors' knowledge. Multivariate analyses for these six compounds indicated that firefighter rank, fire response rates, and years in the fire service were poor indicators of increased occupational exposure. The greatest on-duty exposures to PBDEs were found in the low-call volume department among operational firefighters. Dog tags from firefighters at the high-call volume department accounted for 75% of PCB detections; one particular fire response may have contributed to this. Additionally, there was measurable similarity in total chemical exposure profiles between paired on- and off-duty tags for some firefighters. IMPACT: This study used personal silicone passive samplers in the configuration of dog tags worn around the neck to quantify firefighter occupational exposure in on-duty samples relative to paired off-duty samples for several chemical categories: flame retardants, VOCs, and PCBs. Five PBDEs and sec-butylbenzene were identified as potential occupational exposures, however their prevalence in on-duty tags was not associated with frequency of fire responses, firefighter rank, or years the firefighter has been in the fire service. Additionally, similarity between chemical exposures in on- and off-duty tags from the same firefighter invites further investigation into individual behaviors influencing occupational and para-occupational exposures.

Unravelling soft interfaces: Visualization of gel ridges.

HYPOTHESIS: Soft materials, particularly elastomers, are extensively studied, but investigations into purely soft gel contact systems are limited due to their complex dual phases consisting of polymer and free liquids. While Dual Wavelength-Reflection Interference Confocal Microscopy (DW-RICM) is effective for noninvasively visualizing interfaces from a bottom view, it faces challenges in gel studies due to close refractive indices of polymeric networks and free liquids. We hypothesize that modulating the refractive index of soft gels using nanoparticles (NPs) enhances the visualization of contact zone beneath the free surface, providing insights into the configuration of phase-separated free oil within gel-on-gel contact systems. EXPERIMENTS: Gel-on-gel contact systems were fabricated using immiscible organogels and hydrogels. Titanium dioxide (TiO2) NPs were introduced into the organogel to modulate refractive indices. Given the lack of prior studies on the hidden contact zone between gels, various techniques, including DW-RICM, side-view imaging, and inverted optical microscopy, were employed to observe and validate our findings. Comparative analyses were conducted with elastomer-on-rigid, elastomer-on-gel, and gel-on-rigid contact systems. FINDINGS: Our investigation demonstrated that a minimal amount of TiO2 NPs effectively delineates the direct contact radius between organogel polymeric networks and hydrogel surfaces. Comparative experiments showed that TiO2 addition did not alter the gels' mechanical and surface properties but significantly enhanced information on gel contact deformation. This enhanced visualization technique has the potential to advance our understanding of adhesive contacts in gels, providing valuable insights into interface phenomena involving biological soft tissues and cells.

Greater molecular potential for glucose metabolism in adipose tissue and skeletal muscle of women compared with men.

Women typically have less muscle mass and more fat mass than men, while at the same time possessing similar or even greater whole-body insulin sensitivity. Our study aimed to investigate the molecular factors in primarily adipose tissue, but also in skeletal muscle, contributing to this sex difference. In healthy, moderately active premenopausal women and men with normal weight (28 ± 5 and 23 ± 3 years old; BMI 22.2 ± 1.9 and 23.7 ± 1.7) and in healthy, recreationally active women and men with overweight (32.2 ± 6 and 31.0 ± 5 years old; BMI 29.8 ± 4.3 & 30.9 ± 3.7) matched at age, BMI, and fitness level, we assessed insulin sensitivity and glucose tolerance with a hyperinsulinemic-euglycemic clamp or oral glucose tolerance test and studied subcutaneous adipose tissue and skeletal muscle samples with western blotting. Additionally, we traced glucose-stimulated glucose disposal in adipose tissues of female and male C57BL/6J littermate mice aged 16 weeks and measured glucose metabolic proteins. Our findings revealed greater protein expression related to glucose disposal in the subcutaneous adipose tissue (AKT2, insulin receptor, glucose transport 4) and skeletal muscle (hexokinase II, pyruvate dehydrogenase) in women compared to matched men with normal weight and with overweight. This increased protein capacity for glucose uptake extended to white adipose tissues of mice accompanied with ~2-fold greater glucose uptake compared to male mice. Furthermore, even in the obese state, women displayed better glucose tolerance than matched men, despite having 46% body fat and 20 kg less lean mass. In conclusion, our findings suggest that the superior potential for glucose disposal in female subcutaneous adipose tissue and skeletal muscle, driven by greater expression of various glucose metabolic proteins, compensates for their lower muscle mass. This likely explains women's superior glucose tolerance and tissue insulin sensitivity compared to men.