Is the Compassion of Anesthesiologists Associated With Postoperative Pain and Patient Experience? A Prospective Cohort Study.

BACKGROUND: Patient perception of physician compassion may be associated with improved health outcomes, yet it is unclear whether it is associated with postoperative pain reduction or improved patient experience metrics in same-day surgery patients. We hypothesized that higher anesthesiologist compassion during the preanesthesia interview, rated by patients, is associated with lower postoperative pain via the anxiety pathway in same-day surgery patients. We also performed exploratory correlation analysis to assess whether compassion was associated with less opioid consumption and improved patient experience in same-day surgery patients. METHODS: We conducted a single-center, prospective, observational cohort study in American Society of Anesthesiologists (ASA) physical status I to III patients scheduled to undergo same-day surgery with anesthesia. Compassion was scored using a validated 5-item tool. State anxiety (SA) and trait anxiety (TA) were measured using the State-Trait Anxiety Inventory. Pain scores were obtained using a 0 to 10 Likert scale. Daily opioid use was recorded. Patient experience was assessed using the Consumer Assessment of Healthcare Providers and Systems Outpatient and Ambulatory Surgery Survey (OAS CAHPS) and the Surgical Care CAHPS. Mediation analysis was used to assess the association between compassion and pain scores via the anxiety pathway. Spearman correlation was performed to test for association between the compassion score and the secondary outcomes. RESULTS: A total of 147 subjects completed the study with a median age of 50 years and 81% female. Fifty percent underwent breast surgery, 35% abdominal surgery, and the rest underwent gynecological and urological surgeries. The median (Q1-Q3) postoperative pain scores on postoperative days 0 and 3 days later were 4 (1.5-6) and 3 (1-5), respectively.Mediation analysis results showed a same-day anxiety-mediated effect (95% confidence interval [CI]) of compassion on pain of -0.08 (-0.13 to -0.02), attributing to 9% of the total effect. On postoperative day 0, an increase in compassion was associated with a significant average drop in pain of between 0.02 and 0.13. In addition, higher compassion was correlated with better patient experience metrics (ρ= -0.53 [95% CI, -0.64 to -0.39]). CONCLUSIONS: The study results suggest that an anxiety-mediated pathway exists through which compassionate care may help improve the patient's perception of postoperative pain on the day of surgery (before discharge from the hospital). Higher compassion was also associated with better patient experience metrics.

Complications of Transesophageal Echocardiography: A Review of Injuries, Risk Factors, and Management.

Transesophageal echocardiography (TEE) use has become widespread in cardiac surgical operating rooms over the last 2 decades. Surgical and medical decision-making often are guided by the findings of the TEE examination, rendering TEE an invaluable tool both inside and outside the operating room. TEE has become ubiquitous in some parts because it is considered safe and relatively noninvasive. However, it is imperative for clinicians to understand that TEE can cause severe and possibly life-threatening complications, and the risks of TEE must be balanced against its benefits as a diagnostic tool. Upper gastrointestinal (UGI) injuries are the most commonly described complications of TEE; however, the relative infrequency of injuries and lack of uniform reporting make it difficult to definitively identify potential risk factors. Some large retrospective trials suggested that patient factors (age, body mass index, anatomic abnormalities), comorbid conditions (previous stroke), and procedural variables (procedure time, cardiopulmonary bypass time, etc.) are associated with TEE-related injuries. In this narrative review of complications from TEE, the authors focus on the incidence of UGI injuries, the spectrum of injuries associated with TEE, risk factors that may contribute to UGI injuries, as well as diagnosis and management options. Lastly, the discussion focuses on the prevention of injuries as TEE use continues to become more prevalent.

Blunt Trauma to the Heart: A Review of Pathophysiology and Current Management.

Blunt cardiac injury (BCI), defined as an injury to the heart from blunt force trauma, ranges from minor to life-threatening. The majority of BCIs are due to motor vehicle accidents; however, injuries caused by falls, blasts, and sports-related injuries also can be sources of BCI. A significant proportion of patients with BCI do not survive long enough to receive medical care, succumbing to their injuries at the scene of the accident. Additionally, patients with blunt trauma often have coexisting injuries (brain, spine, orthopedic) that can obscure the clinical picture; therefore, a high degree of suspicion often is required to diagnose BCI. Traditionally, hemodynamically stable injuries suspicious for BCI have been evaluated with electrocardiograms and chest radiographs, whereas hemodynamically unstable BCIs have received operative intervention. More recently, computed tomography and echocardiography increasingly have been utilized to identify injuries more rapidly in hemodynamically unstable patients. Transesophageal echocardiography can play an important role in the diagnosis and management of several BCIs that require operative repair. Close communication with the surgical team and access to blood products for potentially massive transfusion also play key roles in maintaining hemodynamic stability. With proper surgical and anesthetic care, survival in cases involving urgent cardiac repair can reach 66%-to-75%. This narrative review focuses on the types of cardiac injuries that are caused by blunt chest trauma, the modalities and techniques currently used to diagnose BCI, and the perioperative management of injuries that require surgical correction.

Contemporary Challenges for Fellowship Training in Adult Cardiothoracic Anesthesiology: Perspectives From Program Directors Around the United States.

The fellowship in adult cardiothoracic anesthesiology has matured as an accredited program. This special article addresses current challenges in this educational milieu. The first challenge relates to serving as a program director in the contemporary era. The second challenge deals with the accreditation process, including the site visit. The third challenge discusses the integration of structural heart disease and interventional echocardiography into daily practice. The fourth challenge deals with the issues that face fellowship education in the near future. Taken together, these perspectives provide a review of the contemporary challenges facing fellowship education in adult cardiothoracic anesthesiology.

Application of a multi-layer systems toxicology framework for in vitro assessment of the biological effects of Classic Tobacco e-liquid and its corresponding aerosol using an e-cigarette device with MESH™ technology.

We previously proposed a systems toxicology framework for in vitro assessment of e-liquids. The framework starts with the first layer aimed at screening the potential toxicity of e-liquids, followed by the second layer aimed at investigating the toxicity-related mechanism of e-liquids, and finally, the third layer aimed at evaluating the toxicity-related mechanism of the corresponding aerosols. In this work, we applied this framework to assess the impact of the e-liquid MESH Classic Tobacco and its aerosol compared with that of cigarette smoke (CS) from the 3R4F reference cigarette. In the first layer, we evaluated the cytotoxicity profile of the MESH Classic Tobacco e-liquid (containing humectants, nicotine, and flavors) and its Base e-liquid (containing humectant and nicotine only) in comparison with total particulate matter (TPM) of 3R4F CS using primary bronchial epithelial cell cultures. In the second layer, the same culture model was used to explore changes in specific markers using high-content screening assays to identify potential toxicity-related mechanisms induced by the MESH Classic Tobacco and Base e-liquids beyond cell viability in comparison with the 3R4F CS TPM-induced effects. Finally, in the third layer, we compared the impact of exposure to the MESH Classic Tobacco or Base aerosols with 3R4F CS using human organotypic air-liquid interface buccal and small airway epithelial cultures. The results showed that the cytotoxicity of the MESH Classic Tobacco liquid was similar to the Base liquid but lower than 3R4F CS TPM at comparable nicotine concentrations. Relative to 3R4F CS exposure, MESH Classic Tobacco aerosol exposure did not cause tissue damage and elicited lower changes in the mRNA, microRNA, and protein markers. In the context of tobacco harm reduction strategy, the framework is suitable to assess the potential-reduced impact of electronic cigarette aerosol relative to CS.

Biological changes in C57BL/6 mice following 3 weeks of inhalation exposure to cigarette smoke or e-vapor aerosols.

We compared early biological changes in mice after inhalation exposures to cigarette smoke or e-vapor aerosols (MarkTen® cartridge with Carrier, Test-1, or Test-2 formulations; 4% nicotine). Female C57BL/6 mice were exposed to 3R4F cigarette smoke or e-vapor aerosols by nose-only inhalation for up to 4 hours/day, 5 days/week, for 3 weeks. The 3R4F and e-vapor exposures were set to match the target nose port aerosol nicotine concentration (∼41 µg/L). Only the 3R4F group showed postexposure clinical signs such as tremors and lethargy. At necropsy, the 3R4F group had significant increases in lung weight and changes in bronchoalveolar lavage parameters, as well as microscopic findings in the respiratory tract. The e-vapor groups had minimal microscopic changes, including squamous metaplasia in laryngeal epiglottis, and histiocytic infiltrates in the lung (Test-2 group only). The 3R4F group had a higher incidence and severity of microscopic findings compared to any e-vapor group. Transcriptomic analysis also showed that the 3R4F group had the highest number of differentially expressed genes compared to Sham Control. Among e-vapor groups, Test-2 group had more differentially expressed genes but the magnitude of gene expression-based network perturbations in all e-vapor groups was ∼94% less than the 3R4F group. On proteome analysis in the lung, differentially regulated proteins were detected in the 3R4F group only. In conclusion, 3-weeks of 3R4F exposure induced molecular and microscopic changes associated with smoking-related diseases in the respiratory tract, while e-vapor exposures showed substantially reduced biological activities.

Systems Toxicology Assessment of the Biological Impact of a Candidate Modified Risk Tobacco Product on Human Organotypic Oral Epithelial Cultures.

Cigarette smoke (CS) has been reported to increase predisposition to oral cancer and is also recognized as a risk factor for many conditions including periodontal diseases, gingivitis, and other benign mucosal disorders. Smoking cessation remains the most effective approach for minimizing the risk of smoking-related diseases. However, reduction of harmful constituents by heating rather than combusting tobacco, without modifying the amount of nicotine, is a promising new paradigm in harm reduction. In this study, we compared effects of exposure to aerosol derived from a candidate modified risk tobacco product, the tobacco heating system (THS) 2.2, with those of CS generated from the 3R4F reference cigarette. Human organotypic oral epithelial tissue cultures (EpiOral, MatTek Corporation) were exposed for 28 min to 3R4F CS or THS2.2 aerosol, both diluted with air to comparable nicotine concentrations (0.32 or 0.51 mg nicotine/L aerosol/CS for 3R4F and 0.31 or 0.46 mg/L for THS2.2). We also tested one higher concentration (1.09 mg/L) of THS2.2. A systems toxicology approach was employed combining cellular assays (i.e., cytotoxicity and cytochrome P450 activity assays), comprehensive molecular investigations of the buccal epithelial transcriptome (mRNA and miRNA) by means of computational network biology, measurements of secreted proinflammatory markers, and histopathological analysis. We observed that the impact of 3R4F CS was greater than THS2.2 aerosol in terms of cytotoxicity, morphological tissue alterations, and secretion of inflammatory mediators. Analysis of the transcriptomic changes in the exposed oral cultures revealed significant perturbations in various network models such as apoptosis, necroptosis, senescence, xenobiotic metabolism, oxidative stress, and nuclear factor (erythroid-derived 2)-like 2 (NFE2L2) signaling. The stress responses following THS2.2 aerosol exposure were markedly decreased, and the exposed cultures recovered more completely compared with those exposed to 3R4F CS.

Evaluation of the Tobacco Heating System 2.2. Part 7: Systems toxicological assessment of a mentholated version revealed reduced cellular and molecular exposure effects compared with mentholated and non-mentholated cigarette smoke.

Modified risk tobacco products (MRTPs) are being developed with the aim of reducing smoking-related health risks. The Tobacco Heating System 2.2 (THS2.2) is a candidate MRTP that uses the heat-not-burn principle. Here, systems toxicology approaches were engaged to assess the respiratory effects of mentholated THS2.2 (THS2.2M) in a 90-day rat inhalation study (OECD test guideline 413). The standard endpoints were complemented by transcriptomics and quantitative proteomics analyses of respiratory nasal epithelium and lung tissue and by lipidomics analysis of lung tissue. The adaptive response of the respiratory nasal epithelium to conventional cigarette smoke (CS) included squamous cell metaplasia and an inflammatory response, with high correspondence between the molecular and histopathological results. In contrast to CS exposure, the adaptive tissue and molecular changes to THS2.2M aerosol exposure were much weaker and were limited mostly to the highest THS2.2M concentration in female rats. In the lung, CS exposure induced an inflammatory response, triggered cellular stress responses, and affected sphingolipid metabolism. These responses were not observed or were much lower after THS2.2M aerosol exposure. Overall, this system toxicology analysis complements and reconfirms the results from classical toxicological endpoints and further suggests potentially reduced health risks of THS2.2M.

Postoperative Cognitive Dysfunction in the Elderly: A Role for Modafinil.

Introductionː Postoperative cognitive dysfunction has long-term consequences of increased mortality, loss of autonomy, and prolonged hospitalization. We sought to determine whether exposing patients to modafinil may attenuate or prevent this devastating syndrome from affecting the elderly postoperatively. Methodsː Adults aged 65 and older and American Society of Anesthesiologists (ASA) I-III physical status scheduled for elective noncardiac/non-neurosurgical surgery were included. Subjects were tested with the Trail Making Test (TMT) and Rey Auditory Visual Learning Test (RAVLT) preoperatively as well as in the immediate postoperative period, at 1 week, and at 3 months. After baseline testing, patients were randomized into three groups: 0) placebo pre and post-procedure; 1) modafinil only pre-procedure and placebo post-procedure; and 2) modafinil pre and post-procedure. A nonsurgical control group was also utilized. Resultsː Seventy-six subjects completed the trial 3 months post-surgery. The baseline RAVLT obtained was analyzed with 2-way ANOVA with repeated measures and showed improvement in learning in all groups (p = 0.03). At 1-week post-surgery, Group 0 subjects demonstrated no learning improvement in the RAVLT. However, there was a significant improvement in learning in both groups that received modafinil (p<0.01), and in the nonsurgical controls (p<0.01). This learning benefit normalized at 3 months. Conclusionː In this prospective, double-blind, placebo-controlled trial, we found that patients who received modafinil showed improvement in the RAVLT at 1 week. However, this learning benefit normalized at 3 months. Further study should examine dose effect, timing, and route of administration to determine if the effect can be enhanced and if in fact, wakefulness is improved post-surgically.

Comparison of the biological impact of aerosol of e-vapor device with MESH® technology and cigarette smoke on human bronchial and alveolar cultures.

Exposure to aerosol from electronic vapor (e-vapor) products has been suggested to result in less risk of harm to smokers than cigarette smoke (CS) exposure. Although many studies on e-vapor products have tested the effects of liquid formulations on cell cultures, few have evaluated the effects of aerosolized formulations. We examined the effects of acute exposure to the aerosol of an e-vapor device that uses the MESH® technology (IQOS® MESH, Philip Morris International) and to CS from the 3R4F reference cigarette on human organotypic bronchial epithelial culture and alveolar triculture models. In contrast to 3R4F CS exposure, exposure to the IQOS MESH aerosol (Classic Tobacco flavor) did not cause cytotoxicity in bronchial epithelial cultures or alveolar tricultures despite its greater concentrations of deposited nicotine (3- and 4-fold, respectively). CS exposure caused a marked decrease in the frequency and active area of ciliary beating in bronchial cultures, whereas IQOS MESH aerosol exposure did not. Global mRNA expression and secreted protein profiles revealed a significantly lower impact of IQOS MESH aerosol exposure than 3R4F CS exposure. Overall, our whole aerosol exposure study shows a clearly reduced impact of IQOS MESH aerosol relative to CS in bronchial and alveolar cultures, even at greater nicotine doses.

Assessment of in vitro kinetics and biological impact of nebulized trehalose on human bronchial epithelium.

Trehalose is added in drug formulations to act as fillers or improve aerosolization performance. Its characteristics as a carrier molecule have been explored; however, the fate of trehalose in human airway tissues has not been thoroughly investigated. Here, we investigated the fate of nebulized trehalose using in vitro human air-liquid bronchial epithelial cultures. First, a tracing experiment was conducted using 13C12-trehalose; we measured trehalose distribution in different culture compartments (apical surface liquid, epithelial culture, and basal side medium) at various time points following acute exposure to 13C12-labeled trehalose. We found that 13C12-trehalose was metabolized into 13C6-glucose. The data was then used to model the kinetics of trehalose disappearance from the apical surface of bronchial cultures. Secondly, we evaluated the potential adverse effects of nebulized trehalose on the bronchial cultures after they were acutely exposed to nebulized trehalose up to a level just below its solubility limit (50 g/100 g water). We assessed the ciliary beating frequency and histological characteristics. We found that nebulized trehalose did not lead to marked alteration in ciliary beating frequency and morphology of the epithelial cultures. The in vitro testing approach used here may enable the early selection of excipients for future development of inhalation products.

Discriminating Spontaneous From Cigarette Smoke and THS 2.2 Aerosol Exposure-Related Proliferative Lung Lesions in A/J Mice by Using Gene Expression and Mutation Spectrum Data.

Mice, especially A/J mice, have been widely employed to elucidate the underlying mechanisms of lung tumor formation and progression and to derive human-relevant modes of action. Cigarette smoke (CS) exposure induces tumors in the lungs; but, non-exposed A/J mice will also develop lung tumors spontaneously with age, which raises the question of discriminating CS-related lung tumors from spontaneous ones. However, the challenge is that spontaneous tumors are histologically indistinguishable from the tumors occurring in CS-exposed mice. We conducted an 18-month inhalation study in A/J mice to assess the impact of lifetime exposure to Tobacco Heating System (THS) 2.2 aerosol relative to exposure to 3R4F cigarette smoke (CS) on toxicity and carcinogenicity endpoints. To tackle the above challenge, a 13-gene gene signature was developed based on an independent A/J mouse CS exposure study, following by a one-class classifier development based on the current study. Identifying gene signature in one data set and building classifier in another data set addresses the feature/gene selection bias which is a well-known problem in literature. Applied to data from this study, this gene signature classifier distinguished tumors in CS-exposed animals from spontaneous tumors. Lung tumors from THS 2.2 aerosol-exposed mice were significantly different from those of CS-exposed mice but not from spontaneous tumors. The signature was also applied to human lung adenocarcinoma gene expression data (from The Cancer Genome Atlas) and discriminated cancers in never-smokers from those in ever-smokers, suggesting translatability of our signature genes from mice to humans. A possible application of this gene signature is to discriminate lung cancer patients who may benefit from specific treatments (i.e., EGFR tyrosine kinase inhibitors). Mutational spectra from a subset of samples were also utilized for tumor classification, yielding similar results. "Landscaping" the molecular features of A/J mouse lung tumors highlighted, for the first time, a number of events that are also known to play a role in human lung tumorigenesis, such as Lrp1b mutation and Ros1 overexpression. This study shows that omics and computational tools provide useful means of tumor classification where histopathological evaluation alone may be unsatisfactory to distinguish between age- and exposure-related lung tumors.

Comparison of the basic morphology and function of 3D lung epithelial cultures derived from several donors.

In vitro models of the human lung play an essential role in evaluating the toxicity of inhaled compounds and understanding the development of respiratory diseases. Three-dimensional (3D) organotypic models derived from lung basal epithelial cells and grown at the air-liquid interface resemble human airway epithelium in multiple aspects, including morphology, cell composition, transcriptional profile, and xenobiotic metabolism. Whether the different characteristics of basal cell donors have an impact on model characteristics and responses remains unknown. In addition, studies are often conducted with 3D cultures from one donor, assuming a representative response on the population level. Whether this assumption is correct requires further investigation. In this study, we compared the morphology and functionality of 3D organotypic bronchial and small airway cultures from different donors at different weeks after air-lift to assess the interdonor variability in these parameters. The thickness, cell type composition, and transepithelial electrical resistance varied among the donors and over time after air-lift. Cilia beating frequency increased in response to isoproterenol treatment in both culture types, independent of the donor. The cultures presented low basal cytochrome P450 (CYP) 1A1/1B1 activity, but 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) treatment induced CYP1A1/1B1 activity regardless of the donor. In conclusion, lung epithelial cultures prepared from different donors present diverse morphology but similar functionality and metabolic activity, with certain variability in their response to stimulation.

Liposomal Bupivacaine Versus Bupivacaine for Intercostal Nerve Blocks in Thoracic Surgery: A Retrospective Analysis.

BACKGROUND: Liposomal bupivacaine (LipoB), delivered via intercostal nerve blocks (ICNBs), is increasingly being used for postoperative pain control in thoracic surgery patients, but there is limited data on its effectiveness when compared to standard bupivacaine. OBJECTIVE: We sought to compare postoperative opioid use, pain control, and length of stay (LOS) in patients undergoing thoracic surgery with LipoB ICNBs vs patients undergoing thoracic surgery with ICNBs using standard bupivacaine. STUDY DESIGN: A retrospective analysis. SETTING: Research took place in a tertiary academic medical center. METHODS: A transition in the standard of care from standard bupivacaine to LipoB for ICNBs in March of 2014 allowed us to compare 2 cohorts: patients who received bupivacaine ICNBs from January 2013 through February of 2014 and patients who received LipoB ICNBs from March 2015 through November 2017. We included patients who underwent thoracic surgery for lung cancer using robotic-assisted thoracic surgery (RATS), video-assisted thoracic surgery (VATS), or traditional open thoracotomy, and documentation of ICNB in the operative note. We collected data on pain scores (Visual Analog Scale [VAS]) and opioid consumption (converted to oral morphine equivalents [OMEs]) intraoperatively, on postoperative day (POD) 0, POD 1, POD 2, and POD 3. We also analyzed data on length of stay [LOS]. A primary analysis was performed on the effects of LipoB vs bupivacaine across all surgery types on opioid consumption, pain scores, and LOS with a secondary analysis on the same endpoints per individual surgery type. RESULTS: A total of 129 patients were included from the predefined study periods (n = 62 LipoB and n = 67 standard bupivacaine). Across all surgery types, LipoB decreased opioid utilization vs standard bupivacaine (P < .01). Post-hoc testing revealed that this difference existed intraoperatively (55 ± 5 vs 69 ± 4 mg OME, P = .03) and on POD 0 (44 ± 6 vs 68 ± 6 mg OME, P < .01). Surgical subtype analysis revealed that this difference was mostly driven by lower opioid consumption in patients undergoing RATS. When compared across all surgery types, LipoB vs bupivacaine did not affect postoperative pain scores. However, subgroup analysis showed that pain scores were lower in the LipoB vs standard bupivacaine group undergoing VATS on POD 0, 1, and 2. The LOS across all thoracic surgery types was lower in the LipoB group when compared to the standard bupivacaine group (median, 4 days [IQR 2.0-6.0] vs median, 5 days [IQR 3.0-8.0], P < .01). Subgroup analysis showed that the LOS in patients undergoing VATS with LipoB ICNBs was shorter compared to patients receiving bupivacaine ICNBs. LIMITATIONS: The retrospective nature of this study makes it prone to several types of bias. CONCLUSION: ICNBs with LipoB for thoracic surgery leads to lower opioid consumption and shorter LOS when compared to ICNBs with standard bupivacaine. The benefit of LipoB over standard bupivacaine for ICNBs appears especially relevant in VATS or RATS procedures. KEY WORDS: Intercostal nerve block, liposomal bupivacaine, RATS, regional anesthesia, robotic-assisted thoracoscopic surgery, thoracotomy, VATS, video-assisted thoracoscopic surgery.

Structural, functional, and molecular impact on the cardiovascular system in ApoE-/- mice exposed to aerosol from candidate modified risk tobacco products, Carbon Heated Tobacco Product 1.2 and Tobacco Heating System 2.2, compared with cigarette smoke.

AIM: To investigate the molecular, structural, and functional impact of aerosols from candidate modified risk tobacco products (cMRTP), the Carbon Heated Tobacco Product (CHTP) 1.2 and Tobacco Heating System (THS) 2.2, compared with that of mainstream cigarette smoke (CS) on the cardiovascular system of ApoE-/- mice. METHODS: Female ApoE-/- mice were exposed to aerosols from THS 2.2 and CHTP 1.2 or to CS from the 3R4F reference cigarette for up to 6 months at matching nicotine concentrations. A Cessation and a Switching group (3 months exposure to 3R4F CS followed by filtered air or CHTP 1.2 for 3 months) were included. Cardiovascular effects were investigated by echocardiographic, histopathological, immunohistochemical, and transcriptomics analyses. RESULTS: Continuous exposure to cMRTP aerosols did not affect atherosclerosis progression, heart function, left ventricular (LV) structure, or the cardiovascular transcriptome. Exposure to 3R4F CS triggered atherosclerosis progression, reduced systolic ejection fraction and fractional shortening, caused heart LV hypertrophy, and initiated significant dysregulation in the transcriptomes of the heart ventricle and thoracic aorta. Importantly, the structural, functional, and molecular changes caused by 3R4F CS were improved in the smoking cessation and switching groups. CONCLUSION: Exposure to cMRTP aerosols lacked most of the CS exposure-related functional, structural, and molecular effects. Smoking cessation or switching to CHTP 1.2 aerosol caused similar recovery from the 3R4F CS effects in the ApoE-/- model, with no further acceleration of plaque progression beyond the aging-related rate.

Respiratory Effects of Exposure to Aerosol From the Candidate Modified-Risk Tobacco Product THS 2.2 in an 18-Month Systems Toxicology Study With A/J Mice.

Smoking cessation is the most effective measure for reducing the risk of smoking-related diseases. However, switching to less harmful products (modified-risk tobacco products [MRTP]) can be an alternative to help reduce the risk for adult smokers who would otherwise continue to smoke. In an 18-month chronic carcinogenicity/toxicity study in A/J mice (OECD Test Guideline 453), we assessed the aerosol of Tobacco Heating System 2.2 (THS 2.2), a candidate MRTP based on the heat-not-burn principle, compared with 3R4F cigarette smoke (CS). To capture toxicity- and disease-relevant mechanisms, we complemented standard toxicology endpoints with in-depth systems toxicology analyses. In this part of our publication series, we report on integrative assessment of the apical and molecular exposure effects on the respiratory tract (nose, larynx, and lungs). Across the respiratory tract, we found changes in inflammatory response following 3R4F CS exposure (eg, antimicrobial peptide response in the nose), with both shared and distinct oxidative and xenobiotic responses. Compared with 3R4F CS, THS 2.2 aerosol exerted far fewer effects on respiratory tract histology, including adaptive tissue changes in nasal and laryngeal epithelium and inflammation and emphysematous changes in the lungs. Integrative analysis of molecular changes confirmed the substantially lower impact of THS 2.2 aerosol than 3R4F CS on toxicologically and disease-relevant molecular processes such as inflammation, oxidative stress responses, and xenobiotic metabolism. In summary, this work exemplifies how apical and molecular endpoints can be combined effectively for toxicology assessment and further supports findings on the reduced respiratory health risks of THS 2.2 aerosol.

Assessment of a 72-hour repeated exposure to Swedish snus extract and total particulate matter from 3R4F cigarette smoke on gingival organotypic cultures.

Swedish snus is a smokeless tobacco product that contains reduced levels of harmful compounds compared with cigarette smoke. In Sweden, where snus use exceeds smoking among men, relatively low rates of major smoking-related diseases have been recorded. To better understand how snus use could align with current tobacco harm reduction strategies, its potential mechanisms of toxicity must be investigated. This study aimed to determine, via a systems toxicology approach, the biological impact of repeated 72-hour exposure of human gingival epithelial organotypic cultures to extracts from both a commercial and a reference snus and the total particulate matter (TPM) from cigarette smoke. At concentrations relevant for human use, cultures treated with snus extracts induced mild, generally reversible biological changes, while TPM treatment induced substantial morphological and inflammatory alterations. Network enrichment analysis and integrative analysis of the global mRNA and miRNA expression profiles indicated a limited and mostly transient impact of the snus extracts, in particular on xenobiotic metabolism, while the effects of TPM were marked and sustained over time. High-confidence miRNAs that might be related to pathological conditions in vivo were identified. This study highlights the limited biological impact of Swedish snus extract on human organotypic gingival cultures.