Nature prescribing: emerging insights about reconciliation-based and culturally inclusive approaches from a tricultural community health centre. / Prescription d'exposition à la nature : nouvelles perspectives sur les approches fondées sur la réconciliation et l'inclusivité culturelle dans un centre de santé communautaire triculturel.

This commentary highlights the importance of social and nature prescribing programs reflecting culturally diverse perspectives and practices. Creating and holding space for Indigenous and other worldviews should be a key priority of nature prescribing, a relatively recent practice in Canada that recognizes and promotes health benefits associated with engaging in a variety of activities in natural settings. Central to designing and delivering nature prescribing that is culturally inclusive and grounded in fulfilling obligations of reconciliation is recognizing the ongoing dominance of Western worldviews and their associated implications for decolonizing and Indigenizing nature-based programming. Consciously working to expand Western values, with the aim of extending nature prescribing practices beyond mere nature exposure to fostering emotional connections to nature, is a critically important part of the ongoing development of nature-based interventions and nature prescribing.

Nature prescribing is an increasingly recognized aspect of social prescribing that acknowledges and promotes enhanced health benefits associated with natural settings to address illness and promote health and wellness. The Western worldview maintains a narrow view of human relations with nature, consisting of humancentric needs and interests. The limited priority that the Western worldview places on the relationship with nature and the importance of establishing and maintaining nature connection, may limit the potential reach and benefits of nature prescribing. Nature prescribing efforts should recognize pre-existing, nature-based approaches such as land-based healing practised by Indigenous people and ensure culturally inclusive design and practices.

La prescription d'exposition à la nature, une dimension de plus en plus reconnue de la prescription sociale, reconnaît et promeut les bienfaits de l'environnement naturel pour la santé, le bien-être et le traitement des maladies. Le monde occidental entretient une vision étroite des relations entre la nature et l'être humain, qui se résume aux besoins et aux intérêts de ce dernier. La priorité limitée accordée dans le monde occidental à la relation avec la nature et à l'importance des liens avec la nature risque de limiter la portée et les avantages des prescriptions d'exposition à la nature. Les efforts en matière de prescription d'exposition à la nature devraient tenir compte des approches antérieures fondées sur la nature, comme la guérison par la terre pratiquée par les Autochtones, et assurer l'inclusivité culturelle sur le plan de la conception et des pratiques.

The impact of clinical genome sequencing in a global population with suspected rare genetic disease.

There is mounting evidence of the value of clinical genome sequencing (cGS) in individuals with suspected rare genetic disease (RGD), but cGS performance and impact on clinical care in a diverse population drawn from both high-income countries (HICs) and low- and middle-income countries (LMICs) has not been investigated. The iHope program, a philanthropic cGS initiative, established a network of 24 clinical sites in eight countries through which it provided cGS to individuals with signs or symptoms of an RGD and constrained access to molecular testing. A total of 1,004 individuals (median age, 6.5 years; 53.5% male) with diverse ancestral backgrounds (51.8% non-majority European) were assessed from June 2016 to September 2021. The diagnostic yield of cGS was 41.4% (416/1,004), with individuals from LMIC sites 1.7 times more likely to receive a positive test result compared to HIC sites (LMIC 56.5% [195/345] vs. HIC 33.5% [221/659], OR 2.6, 95% CI 1.9-3.4, p < 0.0001). A change in diagnostic evaluation occurred in 76.9% (514/668) of individuals. Change of management, inclusive of specialty referrals, imaging and testing, therapeutic interventions, and palliative care, was reported in 41.4% (285/694) of individuals, which increased to 69.2% (480/694) when genetic counseling and avoidance of additional testing were also included. Individuals from LMIC sites were as likely as their HIC counterparts to experience a change in diagnostic evaluation (OR 6.1, 95% CI 1.1-∞, p = 0.05) and change of management (OR 0.9, 95% CI 0.5-1.3, p = 0.49). Increased access to genomic testing may support diagnostic equity and the reduction of global health care disparities.

Vascular stenting of a malignant arterial blowout as a bridge to effective systemic and regional therapy.

Locally advanced cutaneous squamous cell carcinoma can erode into blood vessels, leading to vascular blowout, requiring emergent surgical intervention. We describe a first case of this disease complication which was effectively managed with endovascular stenting as a bridge to effective systemic and regional therapy. We discuss the efficacy of this staged approach which is novel and timely in a clinical environment of increasingly effective systemic therapies.

Quality of Surgical Care Within the Criminal Justice Health Care System.

Importance: Individuals who are incarcerated represent a vulnerable group due to concerns about their ability to provide voluntary and informed consent, and there are considerable legal protections regarding their participation in medical research. Little is known about the quality of surgical care received by this population. Objective: To evaluate perioperative surgical care provided to patients who are incarcerated within the Texas Department of Criminal Justice (TDCJ) and compare their outcomes with that of the general nonincarcerated population. Design, Setting, and Participants: This cohort study analyzed data from patients who were incarcerated within the TDCJ and underwent general or vascular surgery at the University of Texas Medical Branch (UTMB) from 2012 to 2021. Case-specific outcomes for a subset of these patients and for patients in the general academic medical center population were obtained from the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) and compared. Additional quality metrics (mortality index, length of stay index, and excess hospital days) from the Vizient Clinical Data Base were analyzed for patients in the incarcerated and nonincarcerated groups who underwent surgery at UTMB in 2020 and 2021 to provide additional recent data. Patient-specific demographics, including age, sex, and comorbidities were not available for analysis within this data set. Main Outcome and Measures: Perioperative outcomes (30-day morbidity, mortality, and readmission rates) were compared between the incarcerated and nonincarcerated groups using the Fisher exact test. Results: The sample included data from 6675 patients who were incarcerated and underwent general or vascular surgery at UTMB from 2012 to 2021. The ACS-NSQIP included data (2012-2021) for 2304 patients who were incarcerated and 602 patients who were not and showed that outcomes were comparable between the TDCJ population and that of the general population treated at the academic medical center with regard to 30-day readmission (6.60% vs 5.65%) and mortality (0.91% vs 1.16%). However, 30-day morbidity was significantly higher in the TDCJ population (8.25% vs 5.48%, P = .01). The 2020 and 2021 data from the Vizient Clinical Data Base included 629 patients who were incarcerated and 2614 who were not and showed that the incarcerated and nonincarcerated populations did not differ with regard to 30-day readmission (12.52% vs 11.30%) or morbidity (1.91% vs 2.60%). Although the unadjusted mortality rate was significantly lower in the TDCJ population (1.27% vs 2.68%, P = .04), mortality indexes, which account for case mix index, were similar between the 2 populations (1.17 vs 1.12). Conclusions and Relevance: Findings of this cohort study suggest that patients who are incarcerated have equivalent rates of mortality and readmission compared with a general academic medical center population. Future studies that focus on elucidating the potential factors associated with perioperative morbidity and exploring long-term surgical outcomes in the incarcerated population are warranted.

Swine industry stakeholders' perception on the use of water-based foam as an emergency mass depopulation method.

The U.S. pork supply chain is vulnerable to various internal and external threats and in need of prompt, comprehensive response plans. Under urgent circumstances, for example in the case of foreign disease incursions, swine farms will have to perform on-farm animal depopulation to prevent disease spread. Several animal depopulation methods including water-based foam (WBF) have been proposed and are under evaluation for feasibility in the field. However, the psychological/emotional impacts of applying depopulation methods for personnel managing and carrying on the tasks are not currently well understood. Thus, this study aimed to investigate WBF as an alternative for depopulation compared to existing methods approved by the American Veterinary Medical Association. Swine industry stakeholders were invited to voluntarily observe a WBF depopulation trial and to provide their self-reported perspectives before and after the observation. A survey was designed to explore key areas on expected and perceived method effectiveness, efficiency, and animal welfare considerations, as well as to evaluate short-term post-observation psychological impacts. Among 42 recruited stakeholders, 31.0% (13/42) were educators/researchers followed by animal health officials (26.2%, 11/42) and veterinarians (23.8%, 10/42), with an average of 11.7 ± 12.6 (n = 39) years of work experience. After the trial, respondents' positive perception of WBF depopulation increased specifically regarding the animal loading process being less stressful than restrained in-barn depopulation options (P = 0.003) and by the observation of fewer swine escape attempts and vocalizations than expected (P < 0.001). Respondents' positive perception of WBF also increased regarding to the time required to fill the trailer with foam, to stop hearing animal vocalization, and stop hearing animal movement, as the observed trial times were faster than their pre-observation estimates (P < 0.001). Additionally, 79.5% (31/39) of respondents agreed that the rapid destruction of animal populations had priority over animal welfare under urgent scenarios. Minor post-traumatic stress disorder-like (PTSD-like) symptoms from the observed trials were reported (26.7%, 4/15 respondents) one month after the observation. This study showed that the WBF depopulation process was perceived positively by swine stakeholders and may have limited short-term psychological impacts on personnel involved in animal depopulation.

Characterization of macroalgal-associated microbial communities from shallow to mesophotic depths at Manawai, Papahanaumokuakea Marine National Monument, Hawai'i.

The Papahanaumokuakea Marine National Monument, Hawai'i, is one of the most isolated and protected archipelagos in the world, making it a natural laboratory to examine macroalgal-microbial diversity because of limited direct anthropogenic impacts. We collected the most abundant macroalgae from nine sites ranging from shallow subtidal (1.5 m) to mesophotic (75 m) depths around Manawai (Pearl and Hermes Atoll). We characterized the macroalgal bacterial communities via high-throughput amplicon sequencing and compared the influence of host phylum, species, site, and depth on these relationships at a single atoll. Ochrophyta species had the lowest bacterial diversity compared to Chlorophyta and Rhodophyta. Site and/or depth may influence the microbial community structure associated with Microdictyon setchellianum, indicating a possible disconnect of these microbial communities among habitats. Chondria tumulosa, a cryptogenic species with invasive traits, differed in associated microbiota compared to the native Laurencia galtsoffii, an alga from the same family collected at the same site and depth. While there was overlap of bacterial communities across sites for some algal species, the majority had minimal macroalgal-microbial community connectivity across Manawai. This mesophotic system, therefore, did not appear to be refugia for shallow water coral reefs at microscopic scales. Additional studies are required to identify other significant influences on microbial community variation.

Microbiomes and metabolomes of dominant coral reef primary producers illustrate a potential role for immunolipids in marine symbioses.

The dominant benthic primary producers in coral reef ecosystems are complex holobionts with diverse microbiomes and metabolomes. In this study, we characterize the tissue metabolomes and microbiomes of corals, macroalgae, and crustose coralline algae via an intensive, replicated synoptic survey of a single coral reef system (Waimea Bay, O'ahu, Hawaii) and use these results to define associations between microbial taxa and metabolites specific to different hosts. Our results quantify and constrain the degree of host specificity of tissue metabolomes and microbiomes at both phylum and genus level. Both microbiome and metabolomes were distinct between calcifiers (corals and CCA) and erect macroalgae. Moreover, our multi-omics investigations highlight common lipid-based immune response pathways across host organisms. In addition, we observed strong covariation among several specific microbial taxa and metabolite classes, suggesting new metabolic roles of symbiosis to further explore.

Ureteral reconstruction with appendiceal interposition graft following resection of retroperitoneal leiomyosarcoma.

Ureteral defects can be repaired using a variety of different techniques that depend on the length and position of the defect. Here we describe a case where a long, upper-ureteral defect was successfully reconstructed using an appendiceal interposition graft. A 60-year-old female patient underwent resection of a right-sided retroperitoneal leiomyosarcoma that was encasing the entire upper ureter and obstructing the right kidney. The mass was resected en bloc, leaving behind an 11 cm ureteral defect. The defect was successfully reconstructed with an appendiceal interposition graft. Appendiceal interposition grafts are a feasible and effective approach for ureteral reconstruction in adults following oncologic resection. We describe various technical aspects that optimize the success of ureteral reconstruction.

Decreased SIRT1 Activity Is Involved in the Acute Injury Response of Chondrocytes to Ex Vivo Injurious Mechanical Overload.

A better understanding of molecular events following cartilage injury is required to develop treatments that prevent or delay the onset of trauma-induced osteoarthritis. In this study, alterations to SIRT1 activity in bovine articular cartilage explants were evaluated in the 24 h following a mechanical overload, and the effect of pharmacological SIRT1 activator SRT1720 on acute chondrocyte injury was assessed. SIRT1 enzymatic activity decreased as early as 5 min following the mechanical overload, and remained suppressed for at least 24 h. The chondrocyte injury response, including apoptosis, oxidative stress, secretion of inflammatory mediators, and alterations in cartilage matrix expression, was prevented with pharmacological activation of SIRT1 in a dose-dependent manner. Overall, the results implicate SIRT1 deactivation as a key molecular event in chondrocyte injury following a mechanical impact overload. As decreased SIRT1 signaling is associated with advanced age, these findings suggest that downregulated SIRT1 activity may be common to both age-related and injury-induced osteoarthritis.

Measurement and changes of exhaled nitric oxide fraction while vaping with a brief education intervention session.

A brief, 15-min education intervention session might be helpful to highlight the dangers of vaping and aid in cessation. In addition, post-washout period (15 min), F ENO levels increased significantly. https://bit.ly/3Xu4X5Y.

Predicting General Surgery Match Outcomes Using Standardized Ranking Metrics.

INTRODUCTION: Objective measurements for applicant ranking are becoming increasingly important, not only to help address the growing number of general surgery applicants each year but also to minimize bias and ensure consistency. We assessed if our general surgery applicant scoring system was an effective tool for accurately predicting the results of the resident match. METHODS: A retrospective review of applicant rank lists from 2017 to 2020 was conducted. Applicants were ranked based on the sum of preinterview and interview scores. The preinterview score is an objective metric related to the applicant's academic portfolio. The interview score is a standardized score based on interview performance. We reviewed match results from ranked candidates and categorized them as academic categorical (AC), community categorical (CC), preliminary surgical (PS), nonsurgical specialty (NS), or unmatched (UM) positions. RESULTS: A total of 378 applicants were interviewed. Forty-nine percent matched into AC, 22% into CC, 11% into PS, and 5% into NS positions, while 13% of the interviewees were UM. Applicants who matched into AC positions had significantly higher preinterview and interview scores than applicants in other categories. Applicants who matched into CC positions had significantly higher interview scores than those categorized as UM, but their preinterview scores did not differ significantly from the UM group. Applicants who did not match into a categorical position (PS, NS, or UM) did not have significantly different preinterview or interview scores from one another. CONCLUSIONS: Our standardized scoring system was effective in stratifying which applicants would match into categorical general surgery residency programs.

Remote Instruction in Focused Assessment With Sonography in Trauma (FAST) Exams for Surgery Residents: A Pilot Study.

BACKGROUND: The Focused Assessment with Sonography in Trauma (FAST) exam is an important component to the evaluation of trauma patients. With advances in technology and meeting limitations due to COVID-19, remote instruction and learning have gained popularity. We sought to determine whether remote instruction of FAST exams was feasible as sustainable surgical education and a possible alternative to traditional in-person teaching. METHODS: General surgery residents completed a baseline survey and skills assessment on FAST exams and were then randomized to remote or in-person instruction. The remote group participated in an instructional session with a content expert through video conference and then practiced on a simulated mannequin while the expert remotely provided feedback. The in-person group received the experience with the content expert in the room. Both groups completed a post-course survey immediately after the session and a follow-up survey and objective assessment at six-months. Results were compared with two-way analysis of variance (ANOVA). RESULTS: 14 residents underwent the curriculum, seven in each group. There was a significant increase in self-reported confidence when comparing pre- and immediate post-course results for both the remote and in-person groups. At six months, confidence scores remained elevated and skill assessment scores improved, although the latter did not reach significance. There was no significant difference in post-course results between the groups. CONCLUSIONS: Remote instruction of FAST exams was feasible. Pilot data demonstrated an increase in confidence and suggest outcomes that are similar to in-person instruction, which has positive implications for future remote educational and potentially clinical initiatives.

Versatility of mesenchymal stem cell-derived extracellular vesicles in tissue repair and regenerative applications.

Mesenchymal stem/stromal cells (MSCs) are multipotent somatic cells that have been widely explored in the field of regenerative medicine. MSCs possess the ability to secrete soluble factors as well as lipid bound extracellular vesicles (EVs). MSCs have gained increased interest and attention as a result of their therapeutic properties, which are thought to be attributed to their secretome. However, while the use of MSCs as whole cells pose heterogeneity concerns and survival issues post-transplantation, such limitations are absent in cell-free EV-based treatments. EVs derived from MSCs are promising therapeutic agents for a range of clinical conditions and disorders owing to their immunomodulatory, pro-regenerative, anti-inflammatory, and antifibrotic activity. Recent successes with preclinical studies using EVs for repair and regeneration of damaged tissues such as cardiac tissue, lung, liver, pancreas, bone, skin, cornea, and blood diseases are discussed in this review. We also discuss delivery strategies of EVs using biomaterials as delivery vehicles through systemic or local administration. Despite its effectiveness in preclinical investigations, the application of MSC-EV in clinical settings will necessitate careful consideration surrounding issues such as: i) scalability and isolation, ii) biodistribution, iii) targeting specific tissues, iv) quantification and characterization, and v) safety and efficacy of dosage. The future of EVs in regenerative medicine is promising yet still needs further investigation on enhancing the efficacy, scalability, and potency for clinical applications.

Review and Consultations of Canadian Financial Education Programs for Individuals with Disabilities.

Background. Individuals or persons who live with a disability (PWD) can experience unique financial occupation challenges. Financial education programs can address some challenges. Purpose. The aim of this study was to describe and critically appraise current financial education programs for PWD in Canada. Method. This environmental scan framed by scoping review methods included a critical appraisal of Canadian programs' online content and provider consultations. Researchers used four search methods to identify programs, interviewed service providers from four Canadian programs, and thematically analyzed interview transcripts. Findings. Researchers identified 134 programs; 50 (37.3%) included services. The online content of only 26 (19%) programs explicitly addressed accessibility; 106 (79%) programs' content was at least college reading level. The qualitative results include three themes: (a) individualized approach, (b) "getting the word out", and (c) service growth. Implications. There are financial education programs specific to PWD in Canada. Accessibility, individualization, advocacy, and development are needed.

A Photochemical Crosslinking Approach to Enhance Resistance to Mechanical Wear and Biochemical Degradation of Articular Cartilage.

OBJECTIVE: The objective of this study was to evaluate photochemical crosslinking using Al(III) phthalocyanine chloride tetrasulfonic acid (CASPc) and light with a wavelength of 670 nm as a potential therapy to strengthen articular cartilage and prevent tissue degradation. DESIGN: Changes in viscoelastic properties with indentation were used to identify 2 crosslinking protocols for further testing. Crosslinked cartilage was subjected to an in vitro, accelerated wear test. The ability of the crosslinked tissue to resist biochemical degradation via collagenase was also measured. To better understand how photochemical crosslinking with CASPc varies through the depth of the tissue, the distribution of photo-initiator and penetration of light through the tissue depth was characterized. Finally, the effect of CASPc on chondrocyte viability and of co-treatment with an antioxidant was evaluated. RESULTS: The equilibrium modulus was the most sensitive viscoelastic measure of crosslinking. Crosslinking decreased both mechanical wear and collagenase digestion compared with control cartilage. These beneficial effects were realized despite the fact that crosslinking appeared to be localized to a region near the articular surface. In addition, chondrocyte viability was maintained in crosslinked tissue treated with antioxidants. CONCLUSION: These results suggest that photochemical crosslinking with CASPc and 670 nm light holds promise as a potential therapy to prevent cartilage degeneration by protecting cartilage from mechanical wear and biochemical degradation. Limitations were also evident, however, as an antioxidant treatment was necessary to maintain chondrocyte viability in crosslinked tissue.

Reviewing ACGME Plastic Surgery Fellowship Case Logs: Is Surgical Experience Increasing?

INTRODUCTION: Over the last decade, there has been a 32% decrease in independent plastic surgery fellowships. The growing prevalence of 6-year integrated plastic surgery residencies, duty hour restrictions, and new subspecialty training fellowships for general surgeons have changed the training experience of plastic surgery fellows. METHODS: A retrospective review of the Accreditation Council for Graduate Medical Education (ACGME) case logs for graduating fellows of independent plastic surgery fellowships in the United States was conducted from 2011 to 2019. A linear regression analysis was conducted for each case log code and category, and a 95% level of confidence was assumed (α = 0.05). RESULTS: In 2011, 141 residents from 69 programs graduated with an average of 1469.7 cases. In 2019, 84 residents from 47 programs graduated with an average of 1952 cases. Index procedures significantly increased overall during the 9 y (P < 0.001). Categorical cases increased in esthetics (P < 0.001), including facelift, browlift, blepharoplasty, and more. Categorical cases increased in reconstructive surgery (P < 0.001), including treatment of deformities of the skin, lower extremities, and trunk, nerve decompression, and hand reconstruction. In breast procedures, an increase was seen in the reduction of mammoplasty, reconstruction, and treatment of other breast deformities. In head and neck procedures, an increase was seen in resection of head and neck neoplasms and secondary cleft lip repair. Decreases in procedural numbers were seen in primary cleft lip repair and hand reconstruction by primary closure. CONCLUSIONS: Despite a 32% decline in the number of independent plastic surgery fellowships over the last 9 y, plastic surgery fellows are obtaining significantly more surgical experience, both in esthetic and reconstructive surgery.

Extracorporeal Membrane Oxygenation for Pediatric Burn Patients: Is Management Improving Over Time?

Over the last few decades, extracorporeal membrane oxygenation (ECMO) has become a lifesaving modality for patients with severe respiratory failure following burn injury. With the advancement in critical care and ECMO management, this study aims to analyze the outcomes of ECMO in pediatric burn patients. The Extracorporeal Life Support Organization database was queried from 1999 to 2018 for patients 18 years old and under with a burn injury. The data were divided into two decades, the first (1999-2008) and the second (2009-2018), for analysis of background characteristics and clinical outcomes. Ninety-five patients met inclusion criteria. The overall use of ECMO increased in the second decade (60 cases) when compared to the first decade (35 cases), and use of venovenous ECMO increased in the second decade from 16 cases to 38 cases. Although more patients survived because of the increased application of venovenous ECMO, the survival rate was unchanged between decades (53.4% vs. 54.3%; P = 0.937). Patients with pre-ECMO cardiac arrest had a significant improvement in mortality during the second decade (54.5% vs. 0%; P = 0.043). Metabolic (P = 0.022) and renal (P = 0.043) complications were most common in nonsurvivors during the first decade whereas cardiovascular (P = 0.031) and neurologic (P = 0.003) complication were higher in the second decade (P = 0.031, 0.003). Use of ECMO after burn injury has become more common; however, overall mortality remains unchanged. The data suggests pre-ECMO cardiac arrest is no longer a contraindication to start ECMO.

Value Analysis of Central Line Simulation-Based Education.

BACKGROUND: Central line-associated bloodstream infections (CLABSIs) are preventable complications that pose a significant health risk to patients and place a financial burden on hospitals. Central line simulation-based education (SBE) efforts vary widely in the literature. The aim of this study was to perform a value analysis of published central line SBE and develop a refined method of studying central line SBE. METHODS: A database search of PubMed Central and Cumulative Index to Nursing and Allied Health Literature (CINAHL) was performed for articles mentioning "Cost and CLABSI," "Cost and Central line Associated Bloodstream Infections," and "Cost and Central Line" in their abstract and article body. Articles chosen for qualitative synthesis mentioned "simulation" in their abstract and article body and were analyzed based on the following criteria: infection rate before vs. after SBE, cost of simulation, SBE design including simulator model used, and learner analysis. RESULTS: Of 215 articles identified, 23 were analyzed, 10 (43.48%) discussed cost of central line simulation with varying criteria for cost reporting, 8 (34.8%) numerically discussed central line complication rates (7 CLABSIs and 1 pneumothorax), and only 3 (13%) discussed both (Figure). Only 1 addressed the true cost of simulation (including space rental, equipment startup costs, and faculty salary) and its longitudinal effect on CLABSIs. CONCLUSION: Current literature on central line SBE efforts lacks value propositions. Due to the lack of value-based data in the area of central line SBE, the authors propose a cost reporting standard for use by future studies reporting central line SBE costs.

Spontaneous resolution of gastric perforation caused by an ingested foreign body: a case report.

Foreign body ingestions are commonly seen and are usually uneventful. Very rarely, ingested foreign bodies will cause perforation of the gastrointestinal tract, which can lead to peritonitis, abscesses or fistulation. This is the case of a patient with vague abdominal pain after voluntary ingestion of bleach and an ink pen. The ink pen was found lodged in the gastric antral wall on esophagogastroduodenoscopy. The foreign body spontaneously migrated into the gastric lumen and was successfully removed with endoscopy.

Evaluation of secondary electronic cigarette inhalation on lipid metabolism in C57BL/6J mice using indirect calorimetry.

The disruption of glucose homeostasis associated with the use of nicotine delivery systems may be due to a shift to lipid metabolism. Indirect calorimetry was used to measure the respiratory exchange ratio (RER) in female (N = 21) and male (N = 21) C57BL/6J mice exposed to room air (control) or e-cigarette vapor in a 1L chamber to test the hypothesis that lipid metabolism predominates in vaped mice. Metabolism was quantified via RER using a GA-200 gas analyzer (iWorx, Inc) and LabScribe v.4 (iWorx, Inc.) software. Blood glucose levels were assessed from a subset of the population using an Accu-Check glucometer (Roche Diagnostics, Inc.). Statistical analyses were conducted using R v.4.0.3. Median RER for controls was lower in females. Older females showed a reduction in RER when exposure occurred in the afternoon (p < 0.001), and in males when exposure occurred in the morning (p = 0.007). Glucose concentrations (mg/dL) were higher after e-cigarette inhalation compared with controls, but this difference was not significant (p = 0.464). The reduction in the respiratory exchange ratio supports the hypothesis that e-cigarette inhalation promotes lipid metabolism, and the magnitude of the effect is influenced by gender, age and time of day.