Treatment effects are often anticipated to vary across groups of patients with different baseline risk. The Predictive Approaches to Treatment Effect Heterogeneity (PATH) statement focused on baseline risk as a robust predictor of treatment effect and provided guidance on risk-based assessment of treatment effect heterogeneity in a randomized controlled trial. The aim of this study is to extend this approach to the observational setting using a standardized scalable framework. The proposed framework consists of five steps: (1) definition of the research aim, i.e., the population, the treatment, the comparator and the outcome(s) of interest; (2) identification of relevant databases; (3) development of a prediction model for the outcome(s) of interest; (4) estimation of relative and absolute treatment effect within strata of predicted risk, after adjusting for observed confounding; (5) presentation of the results. We demonstrate our framework by evaluating heterogeneity of the effect of thiazide or thiazide-like diuretics versus angiotensin-converting enzyme inhibitors on three efficacy and nine safety outcomes across three observational databases. We provide a publicly available R software package for applying this framework to any database mapped to the Observational Medical Outcomes Partnership Common Data Model. In our demonstration, patients at low risk of acute myocardial infarction receive negligible absolute benefits for all three efficacy outcomes, though they are more pronounced in the highest risk group, especially for acute myocardial infarction. Our framework allows for the evaluation of differential treatment effects across risk strata, which offers the opportunity to consider the benefit-harm trade-off between alternative treatments. Understanding this heterogeneity of treatment effects (HTE) has been crucial for both personalized (or precision) medicine and comparative effectiveness research, giving rise to a wide range of approaches for its discovery, evaluation and application in clinical practice. A common approach to evaluating HTE in clinical trials is through subgroup analyses. However, as these analyses are rarely adequately powered, they can lead to false conclusions of absence of HTE or exaggerate its presence4. In addition, patients differ in multiple characteristics simultaneously, resulting in much richer HTE compared to the heterogeneity explored with regular one-variable-at-a-time subgroup analyses.Treatment effects often vary substantially across individual patients, causing overall effect estimates to be inaccurate for a significant proportion of the patients at hand8. For example, an invasive coronary procedure—compared to medical treatment—improves survival in patients with myocardial infarction at high (predicted) baseline risk but not in those at low baseline risk9. It has also been shown that high-risk patients with pre-diabetes benefit substantially more from a lifestyle modification program than low-risk patients10.Baseline risk is a summary score inherently related to treatment effect that can be used to represent the variability in patient characteristics12. After risk-stratifying patients using an existing or an internally derived prediction model, risk stratum-specific estimates of relative and absolute treatment effect are evaluated. Several methods for predictive HTE analysis have been adapted for use in observational data, but risk-based methods are still not readily available and have been highlighted as an important future research need12.The recently proposed Predictive Approaches to Treatment effect Heterogeneity (PATH) statement provides systematic guidance on the application of risk-based methods for the assessment of HTE in randomized controlled trial (RCT) data14. A standardized framework applying current best practices for comparative effectiveness studies within the OHDSI setting has been proposed15. This framework was successfully implemented in the Large-scale Evidence Generation and Evaluation across a Network of Databases for Hypertension (LEGEND-HTN) study. In this study, average effects of all first-line hypertension treatment classes were estimated for a total of 55 outcomes across a global network of nine observational databases16.The Observational Health Data Science and Informatics (OHDSI) collaborative has established a global network of data partners and researchers that aim to bring out the value of health data through large-scale analytics by mapping local databases to the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM)LEGEND-HTN found benefit for patients treated with thiazide or thiazide-like diuretics compared to angiotensin-converting enzyme (ACE) inhibitors in terms of three main outcomes of interest, i.e., acute myocardial infarction (MI), hospitalization with heart failure, and stroke. Thiazide or thiazide-like diuretics also had a better safety profile compared to ACE inhibitors which, according to that study, makes them an attractive option for first-line treatment of hypertension. However, as already pointed out, overall (average) effect estimates may not be applicable to large portions of the target population due to strong variability of important patient characteristics. A risk-based analysis of treatment effect heterogeneity can add further insights to the results of LEGEND-HTN, both in understanding how treatment effects evolve with increasing baseline outcome risk and in identifying patient subgroups, which could be targeted with a certain treatment.Hereto, we focus on the three main outcomes of LEGEND-HTN  and nine safety outcomes . For our analyses, we develop a systematic framework for risk-based assessment of treatment effect heterogeneity in observational healthcare databases, extending the existing methodology from the RCT setting. The suggested framework is also implemented in an open-source, publicly available R-package. It is highly scalable and can be easily implemented across a network of observational databases mapped to OMOP-CDM.https://github.com/OHDSI/RiskStratifiedEstimation). An overview of the entire framework can be found in Fig. The proposed framework defines 5 distinct steps: 1) definition of the research aim; (2) identification of the databases within which the analyses will be performed; (3) prediction of outcomes of interest; (4) estimation of absolute and relative treatment effects within risk strata; (5) presentation of the results. We developed an open-source R-package for the implementation of the proposed framework and made it publicly available  and nine safety outcomes . We used data from three US-based claims databases.Treatment cohort: Patients receiving any drug within the class of thiazide or thiazide-like diuretics with at least one year of follow-up before treatment initiation and a recorded hypertension diagnosis within that year.Comparator cohort: Patients receiving any drug within the ACE inhibitor class with at least one year of follow-up before treatment initiation and a recorded hypertension diagnosis within that year.Outcome cohorts: We considered three efficacy and nine safety outcome cohorts. These were patients in the database with a diagnosis of: acute MI; hospitalization with heart failure; ischemic or hemorrhagic stroke (efficacy outcomes); acute renal failure; kidney disease; cough; hyperkalemia; hypokalemia; gastrointestinal bleeding; hyponatremia; hypotension; angioedema (safety outcomes).We considered the following research aim: “compare the effect of thiazide or thiazide-like diuretics , IBM® MarketScan® Multi-State Medicaid (MDCD), and IBM® MarketScan® Medicare Supplemental Beneficiaries (MDCR). More information on the included databases can be found in Supplementary Results We internally developed separate prediction models for 2-year acute MI risk in each of the three databases. The prediction models were fitted on the propensity score-matched (1:1) subset of the entire study population, using a caliper of 0.2 and after excluding patients having the outcome at any time prior to treatment initiation. We considered a large set of candidate predictors containing patients’ demographic information , disease and medication history, and the Charlson comorbidity index (Romano adaptation) measured in the year prior to treatment initiation. As all three databases are mapped to OMOP-CDM, coding of all predictors was uniform across databases. This enables the development of the prediction models for acute MI risk in a uniform fashion across databases. However, due to the differences in data capture among databases, we cannot expect that all covariates will be present in all databases. We developed the prediction models using LASSO logistic regression with 3-fold cross validation for hyper-parameter selection. In Supplementary Table The models had moderate discriminative ability  in CCAE and MDCD and lower discriminative ability in MDCR Table .Table 2PIn each database, we used patient-level predictions of the internally derived acute MI risk prediction model to stratify the patients into three acute MI risk groups RG-1, RG-2, and RG-3 . Within risk groups, in order to account for observed confounding, we further stratified the patients into five propensity score strata. Propensity score models were developed within each risk group separately using the same approach as in step 3 (LASSO logistic regression with a large set of predefined covariates). Risk group-specific relative treatment effects were estimated by averaging over the hazard ratio estimates derived from Cox regression models fitted in each propensity score stratum. Similarly, risk group-specific absolute treatment effects were estimated by averaging over the differences in Kaplan-Meier estimates in each propensity score stratum at 2 years after treatment initiation.In all databases we found adequate overlap of the propensity score distributions across the risk groups, except for high-risk patients in CCAE (acute MI risk above 1.5%). Hence, the propensity scores should be able to adjust for observed confounding, except for high-risk CCAE patients Fig. . The cov19. Hazard ratios for CCAE  relative treatment effect estimates of thiazide or thiazide-like diuretics versus ACE inhibitors varied substantially across risk groups, but no clear trends indicating an association between risk and relative treatment effect estimates were observed Fig. .Fig. 5ReFor acute MI, hazard ratios showed an increasing trend with increasing baseline acute MI risk in MDCD and CCAE, implying larger benefit on the relative scale for patients in the lower risk groups. This was less pronounced in MDCR Fig. ; panel aAbsolute treatment effects (risk reduction) for acute MI and hospitalization with heart failure tended to increase with increasing acute MI risk Fig. ; panel cAcross all databases and all risk groups Fig. , thiazidThe absolute benefit for angioedema of thiazide or thiazide-like diuretics was negligible, despite the large treatment effect estimated on the relative scale Fig. ; panel bThe overall benefits of thiazide or thiazide-like diuretics compared to ACE inhibitors that were observed in MDCR, in terms of acute MI and hospitalization with heart failure, were mainly driven by patients with predicted acute MI risk above 1.5%. Even in MDCD, where benefit on the absolute scale was observed across all acute MI risk strata, treatment effects were much larger in patients with predicted acute MI risk above 1.5%. In CCAE, where the majority of the patients had a predicted acute MI risk below 1%, we found negligible treatment effects. This provides further support for the similarity of the effect of thiazide or thiazide-like diuretics compared to ACE inhibitors in patients at low risk of acute MI.Even though LEGEND-HTN found beneficial effects of thiazide or thiazide-like diuretics over ACE inhibitors in terms of several safety outcomes, there are still safety concerns when prescribing thiazide or thiazide-like diuretics. The hypokalemia and hyponatremia risk increase with thiazide or thiazide-like diuretics was not negligible in any of the acute MI risk strata. On the other hand, ACE inhibitor-related cough risk increase was also present in all databases and acute MI risk groups. Provided that absolute benefits of thiazide or thiazide-like diuretics for the main outcomes  were mainly observed in patients at high acute MI risk, the prescribing physician has to carefully weigh benefits and harms for individual patients.Note that any conclusions drawn are for demonstration purposes only and should be interpreted under this very limited setting.As a sensitivity analysis, we evaluated treatment effect heterogeneity of thiazide or thiazide-like diuretics compared to ACE inhibitors in patients with or without prior cardiovascular disease. We defined the set of patients without prior cardiovascular disease as the patients that had no occurrence in their medical history of any of the following conditions: heart valve disorder or transplanted heart valve, coronary artery disease, cardiac dysfunction, heart block, unstable angina, atrial fibrillation, myocardial infarction, ventricular arrhythmia or cardiac arrest, ischemic heart disease, myocarditis or pericarditis, cardiomyopathy, cardiomegaly, heart failure, or stroke (ischemic or hemorrhagic). If patients had any of these conditions recorded in their medical history, they were assigned to the group with prior cardiovascular disease. We repeated our analyses using the exact same settings for both groups of patients.In patients without prior cardiovascular disease, the estimates of the relative effect of thiazide or thiazide-like diuretics compared to ACE inhibitors on acute MI were similar to the original analyses—hazard ratios 0.90 , 0.52 , and 0.83  in CCAE, MDCD, and MDCR respectively. In patients with prior cardiovascular disease the effect of thiazide or thiazide-like diuretics was stronger in CCAE—hazard ratio 0.73 —but weaker in MDCD and MDCR—hazard ratios 0.78  and 0.88 , respectively. In both sets of sensitivity analyses, risk-stratified results showed trends comparable to the original analysis  and the reliability of data entry should also be considered.In our analyses, we used data from IBM® MarketScan® Commercial Claims and Encounters (CCAE), IBM® MarketScan® Medicaid (MDCD), and IBM® MarketScan® Medicare Supplemental Beneficiaries (MDCR). The New England Institutional Review Board (IRB) has determined that studies conducted in these databases are exempt from study-specific IRB review, as these studies do not qualify as human subjects research.27. We use the derived prediction model to separate the patient population into risk strata, within which treatment effects on both the relative and the absolute scale will be assessed.For our risk-based approach to adequately evaluate treatment effect heterogeneity, a well performing prediction model assigning patient-level risk for the outcome of interest needs to be available, either from literature or internally developed from the data at hand. For internally developing a risk prediction model we adopt a standardized framework focused on observational data that ensures adherence to existing guidelines29. We also need to define a set of patients that experience the outcome of interest, i.e., the outcome cohort. Finally, we need to decide the time frame within which the predictions will be carried out, i.e., the patients’ time at risk. Subsequently, we can develop the prediction model.For the development of the risk prediction model, we first need to define a target cohort of patients, i.e., the set of patients on whom the prediction model will be developed. In our case, the target cohort is generated by pooling the already defined treatment and comparator cohorts. We develop the prediction model on the propensity score-matched (1:1) subset of the pooled sample to avoid differentially fitting between treatment arms, thus introducing spurious interactions with treatmentIt is important that the prediction models display good discriminative ability to ensure that risk-based subgroups are accurately defined. A performance overview of the derived prediction models including discrimination and calibration both in the propensity score-matched subset, the entire sample and separately for treated and comparator patients should also be reported.We estimate treatment effects  within risk strata defined using the prediction model of step 3. We often consider four risk strata, but fewer or more strata can be considered depending on the available power for accurately estimating stratum-specific treatment effects. Effect estimation may be focused on the difference in outcomes for a randomly selected person from the risk stratum (average treatment effect) or for a randomly selected person from the treatment cohort within the risk stratum receiving the treatment under study (average treatment effect on the treated).30.Any appropriate method for the analysis of relative and absolute treatment effects can be considered, as long as the this is done consistently in all risk strata. Common statistical metrics are odds ratios or hazard ratios for relative scale estimates and differences in observed proportions or differences in Kaplan-Meier estimates for absolute scale estimates, depending on the problem at hand. We estimate propensity scores within risk strata which we then use to match patients from different treatment cohorts or to stratify them into groups with similar propensity scores or to weigh each patient’s contribution to the estimation process19.Prior to analyzing results, it is crucial to ensure that all diagnostics are passed in all risk strata. The standard diagnostics we carry out include analysis of the overlap of propensity score distributions and calculation of standardized mean differences of the covariates before and after propensity score adjustment. Finally, we use effect estimates for a large set of negative control outcomes—i.e., outcomes known to not be related with any of the exposures under study—to evaluate the presence of residual confounding not accounted for by propensity score adjustmentIn the presence of a positive treatment effect and a well-discriminating prediction model we expect an increasing pattern of the differences in the absolute scale, even if treatment effects remain constant on the relative scale across risk strata. Owing to this scale-dependence of treatment effect heterogeneity, results should be assessed both on the relative and the absolute scale.Further information on research design is available in the Supplemental MaterialREPORTING SUMMARY


Although considered one of the most effective interventions for substance use disorders (SUD), the widespread uptake of contingency management (CM) has remained limited. Prior studies at the provider-level have explored beliefs about CM among SUD treatment providers and have tailored implementation strategies based on identified barriers and training needs. However, there have been no implementation strategies that have actively sought to identify or address potential differences in the beliefs about CM that could be influenced by the cultural background  of treatment providers. To address this knowledge gap, we examined beliefs about CM among a sample of inpatient and outpatient SUD treatment providers.A cross-sectional survey of SUD treatment providers was completed by 143 respondents. The survey asked respondents about their attitudes toward CM using the Contingency Management Beliefs Questionnaire (CMBQ). Linear mixed models were used to examine the effect of ethnicity on CMBQ subscale  scores.Fifty-nine percent of respondents self-identified as non-Hispanic White and 41% as Hispanic. Findings revealed that SUD providers who identified as Hispanic had significantly higher scores on the general barriers (p < .001) and training-related barriers (p = .020) subscales compared to the non-Hispanic White SUD providers. Post-hoc analyses identified differences in the endorsement of specific individual scale items on the general barriers and training-related subscales.Dissemination and implementation strategies for CM among treatment providers need to consider equity-related factors at the provider-level that may be associated with the adoption and uptake CM. Contingency management (CM) is an evidence-based intervention for substance use disorders (SUD) that provides positive reinforcement  for targeted behaviors such as abstinence or the reduction of substance use . MultiplIn the uptake schema, the pre-implementation phase is characterized as the work needed to understand organizational and provider readiness . Among pIn other behavioral health fields, there has been a few studies that have found an association between the race and/or ethnicity of providers and attitudes towards the general use of evidence-based interventions. For instance, Aaron and colleagues’ findings suggest that Black and Hispanic providers report more negative attitudes toward evidence-based interventions compared to White providers , 2010. IPotential participants were eligible if they were 18 years of age and older, self-identified as currently or previously employed as a provider in an addiction treatment clinic, and reported English language fluency. Potential participants did not need to have prior experience with CM to complete the online survey. Between January 2019 and June 2019, a total of 203 potential participants responded to a targeted email disseminated to professional groups focused on SUD and addiction , who were asked to also share it with other networks. Of those who initially responded, 162 respondents met inclusion criteria, with 143 providing responses on the CMBQ, for a participation rate of 88.3% .To facilitate survey completion, a Research Electronic Data Capture (REDCap)-based electronic survey was used to capture responses from eligible participants and the survey link was embedded in the email distributed to listservs. The result was an “opt-in” nonprobability sample based on participants recruited through the professional group listserv sampling frame. This study was considered exempt by the university’s Institutional Review Board and participants were asked to read and download informed consent forms, and indicate whether they would like to continue to the survey. At the end of the survey, participants were asked to provide their email address to receive a $15 e-gift card for survey completion. The survey was closed after six-months of recruitment and all data were maintained in a secure electronic database.The 32-item Contingency Management Beliefs Questionnaire (CMBQ) was used to assess the level of influence each item has on providers’ decision to adopt the use of CM on a five-point Likert scale . Exploratory and confirmatory factor analysis of CMBQ item scores suggests a stable and reliable three factor structure forming three subscales totaling 32 items: General Barriers (17 items), Training-related Barriers (4 items), and CM-supportive Statements (11 items) . The genData were also collected on key demographic characteristics, such as age, gender , race , ethnicity (non-Hispanic or Hispanic), licensed mental health counselor (LMHC) credential status (yes/no), and graduate degree status (yes/no).Among all respondents, 49% self-identified as non-Hispanic White, 34% as Latinx, 7% as Black, and 10% as an ethnoracial minority. Based on the sparse representation of races and ethnicities other than non-Hispanic White and Hispanic ethnicity, we limited our analyses to these two groups in order to avoid error in interpretation from very small subsamples of other races. Demographic comparisons among non-Hispanic White and Hispanic respondents were appropriate to the scale of measurement: age was compared with independent sample t-tests with all other demographic variables analyzed in two-way contingency table analyses using exact tests to assess for significant differences in proportions by ethnicity. For inferential testing, CMBQ subscale sores were converted to the mean scale score by summing scores for all items completed within a scale and dividing by the number of items completed in the scale. Averaging standardized scales (composed of different numbers of items) for comparison and compensated for the limited amount of non-response within a few respondents, as detailed in the p = .941 and p = .322, respectively). Graduate degree status and age were maintained as covariates in the second model. Model fit to the data improved in the second model based on a reduction in Akaike’s Information Criterion. Both models employed random intercepts for respondents to account for correlation between CMBQ subscales, restricted maximum likelihood estimation, and modeled covariance structure as a scaled identity matrix; both models converged under these criteria.A linear mixed model was used to examine the effect of ethnicity on mean CMBQ subscale scores. Ethnicity was modeled as a binary fixed factor with the each CMBQ subscale scores, representing levels of a second fixed repeated measures factor - scale. The ethnicity and scale interaction term was also modeled as the primary parameter of interest in order to evaluate whether scores on each subscale differed among non-Hispanic White and Hispanic respondents. The initial fully specified model included all demographic variables that differed significantly by ethnicity in univariate analyses as covariates . A second, more parsimonious, model was developed that removed gender and credential status from the model as these were not significant as covariates in the fully specified model  exact tests to explore differences in specific attitudes toward CM among Hispanic and non-Hispanic White respondents. All analyses used two-sided type I error rates of Overall (N = 143), the mean age was 41.0 years, 59% (n = 85) self-identified as non-Hispanic White and 41% (n = 58) as Hispanic. As seen in p = .001) and the repeated measures scale variable (p < .001), after adjustment for age and graduate degree status. These main effects were superseded by a significant ethnicity by CMBQ subscale interaction (p < 001). Simple main effects testing revealed significantly higher general barriers scale scores (p < 001) and training-related barriers scale scores (p = .020) among Hispanic respondents compared to non-Hispanic White respondents. Scores on the CM-Supportive Statement subscale did not differ by ethnicity (p = .853). Interaction means derived from linear mixed modeling are displayed in Linear mixed modeling of CMBQ subscale scores revealed significant main effects by ethnicity . Items with the greatest differences in endorsement among groups (> 40% difference in group proportions) included external barriers  and internal barriers . Differences in endorsement of individual subscale items are displayed in For each of the 17 items in the General Barriers subscale, significantly higher proportions of Hispanic respondents endorsed “some to very strong influence” compared to non-Hispanic White respondents . Similarly, a significantly larger proportion of Hispanic respondents felt their agencies/administrations posed barriers to provision of CM (p = .005) relative to their non-Hispanic White counterparts.On the Training-Related Barriers subscale, significantly higher proportions of Hispanic respondents endorsed “some to very strong influence” than non-Hispanic White respondents need for more CM training  at the provider-level, our findings align with prior work in other areas that have signaled the potential importance of providers’ ethnicity on beliefs and attitudes , which iBroadly, understanding providers’ beliefs and attitudes during the pre-implementation phase is linked to the successful adoption and uptake of an intervention. This also includes identifying whether there are gaps or differences among providers, so that implementation strategies are tailored appropriately. Previous studies have cited that failure to adequately understand providers’ attitudes can hinder the successful implementation of an intervention . A singlThe field of implementation science has more recently called for equity-focused practices in the design and roll-out of strategies . NotwithAmong study limitation is the use of a convenience sample of SUD providers. Based on this, caution should be used when generalizing to other SUD treatment providers. Further, the small number of respondents from Black, American Indian/Alaska Native, and Asian respondents suggests that these results should not be extended to other races. As such future research should examine differences in attitudes and beliefs about CM in a more diverse sample of SUD treatment providers.This study highlights the need for consideration of Hispanic ethnicity as an equity factor at the provider-level, which has not been previously acknowledged during the pre-implementation phase. Understanding the possible influence of providers’ ethnoraical background on the perceived advantages and disadvantages of CM is fundamental to developing equity focused implementation strategies that may aid the adoption of CM among SUD treatment providers.


There is gaining popularity in the use of single-cell technology and analysis in studying the pathogenesis of abdominal aortic aneurysm (AAA). As there are no current pharmacologic therapies for impeding aneurysm growth or preventing AAA rupture, identifying key pathways involved in AAA formation is critical for the development of future therapies. Single-cell RNA sequencing (scRNA-seq) technology provides an unbiased and global view of transcriptomic characteristics within each of the major cell types in aneurysmal tissues. In this brief review, we examine the current literature utilizing scRNA-seq for the analysis of AAA and discuss trends and future utility of this technology. Abdominal aortic aneurysm (AAA) is a complex multifactorial pathologic dilation of the abdominal aorta. AAAs are prevalent in roughly 1–2% of men over the age of 65 years, and nearly 0.5% of women over 70 years old, however, AAA rupture is the leading cause of death in the United States  is a technique used to analyze gene expression at the level of individual cells. Compared to conventional RNA sequencing, which analyzes an average gene expression in bulk tissue samples, scRNA-seq provides a more detailed and precise evaluation of cell heterogeneity within samples, as it can identify rare cell types and even predict cell-cell signaling pathways. Since the discovery of single-cell RNA sequencing (scRNA-seq) by Tang et al. in 2009, the use of this technology has become increasingly embraced in recent years by pathophysiological studies . AnalyseA literature search of publications regarding scRNA sequencing on AAA was performed using the PubMed search engine MEDLINE database. Search terms included (“single-cell RNA” OR “scRNA-seq”) AND “abdominal aortic aneurysm(s)” queried within all fields of text in order to capture the largest number of articles. Only original studies with full text published prior to 2023 were included. Studies were excluded if no new primary scRNA-seq data or in-depth analysis of existing datasets were performed. The model or tissue specimen to which scRNA-seq was performed, the number of cells and clusters, and the major scRNA-seq specific findings were then compared.The above search terms yielded 17 results, of which 2 studies were excluded. One study was excluded as the authors used a previously published scRNA-seq database to identify the presence of an RNA sequence of interest instead of analyzing the dataset . Of the The first publication utilizing scRNA-seq technology for the study of AAA was by Hadi et al. in 2018, using an angiotensin II (Ang II)-induced AAA murine model . A singl2) models. All of these mouse studies used young male mice. In the human dataset, 2 of the 4 AAA tissue samples were from female patients, while both controls (n = 2) were acquired from male patients undergoing aortobifemoral bypass  to identify a specific sequence of interest. One study utilized CellChat analysis to determine intercellular communication pathways by identifying outgoing and incoming signals between cell clusters .−/−ApoE mice that were infused with Ang II  for 28 days, and primarily focused their analysis on a particular tissue cell type (2 (Consistent with the wide use of the Ang II model by other approaches, 4 of the original scRNA-seq studies were conducted with this model . Each ofell type , 13, 15. type (2 , Zhao an type (2 . Despite type (2 ,2.This brief systematic review serves as a resource for the current status of scRNA-seq in AAA. As identified above, scRNA-seq is gaining popularity and utility in AAA, as most studies have been conducted within the past year. Overall, this technology validates the existing understandings of the pathophysiologic mechanisms involved in AAA. Collectively, the scRNA-seq studies highlighted the importance of known pathological processes including inflammation, negative remodeling of extracellular matrix proteins, and phenotypic changes of vascular smooth muscle cells. However, with its capability of resolving transcriptome at a single cell resolution, scRNA-seq additionally provides a clear view on the heterogeneity of each of the major cell types found in aneurysmal tissues. Furthermore, the development of various bioinformatic analytical tools enables delineation of the specific interactions involved within complex pathways and predictions of cellular communications. For example, the scRNA-seq analysis conducted by Hadi et al. provides the precise mechanism infiltrated macrophages activate vascular smooth muscle cells to upregulate matrix metalloprotease-3 transcription and activation, which takes the known inflammatory response to a much deeper depth . SimilarEvaluating AAA using scRNA-seq has its limitations. In terms of scRNA-seq technology, evaluating changes in RNA at the transcriptome level does not necessarily reflect similar changes at the proteomic level. The high specificity of scRNA-seq comes at the cost of reduced sensitivity compared to bulk RNA sequencing, meaning low-abundance transcripts or rare cell phenotypes may be undetected or unrecognized using this method. Additionally, scRNA-seq typically generates low read coverage per cell and often uses short-read sequencing, which can make it difficult to identify alternative splicing events that occur at low levels. The manipulation of cells during ex vivo isolation may also lead to alterations in RNA prior to analysis. Using scRNA-seq for the evaluation of AAA is restricted by the limitations of current animal models and scRNA-seq databases. In mice, the available AAA models utilize only male mice in all the published scRNA-seq work. Although the majority of AAA occur in men, women, particularly postmenopausal women, are also affected by this highly lethal disease. The exclusion of female animals in the scRNA-seq study design diminishes the ability to evaluate sex differences in AAA. It is therefore a plausible progress made by Davis and colleagues to include AAA samples from female patients . HoweverIn summary, scRNA-seq is a powerful research tool which enables unbiased investigation of AAA pathophysiology. Additional datasets from human AAA patients and controls are warranted. Further comparisons between human and murine datasets as well as between male and female datasets are useful in determining which of the complex molecular pathways are likely therapeutic targets.


In humans there is a biological phenomenon known as CHIP  in which somatic (acquired) mutations cause blood cells of a certain type to grow disproportionately by making many copies (or “clones”) of themselves. Although most people who are found to have CHIP do not have cancer, they are known to be at higher risk of developing cancer. CHIP has been studied extensively in humans, where it occurs more frequently with increasing age and is thought to be present in 10–20% of people over the of age 70; however, CHIP has not been well-studied in other species. This study provides the first population-level evidence for the potential existence of CHIP-like findings in dogs. Further research is needed to determine the clinical significance of these findings in canine patients.Age-related somatic genomic alterations in hematopoietic cell lines have been well characterized in humans; however, this phenomenon has not been well studied in other species. Next-generation sequencing-based liquid biopsy testing for cancer detection was recently developed for dogs and has been used to study the genomic profiles of blood samples from thousands of canine patients since 2021. In this study, 4870 client-owned dogs with and without a diagnosis or suspicion of cancer underwent liquid biopsy testing by this method. Copy number variants detected exclusively in genomic DNA derived from white blood cells (WBC gDNA-specific CNVs) were observed in 126 dogs ; these copy number variants were absent from matched plasma cell-free DNA, and from tumor tissue in dogs with concurrent cancer. These findings were more common in older dogs and were persistent in WBC gDNA in over 70% of patients, with little to no change in the amplitude of the signal across longitudinal samples. Many of these alterations were observed at recurrent locations in the genome across subjects; the most common finding was a partial loss on CFA25, typically accompanied by a partial gain on the same chromosome. These early findings suggest that age-related somatic alterations may be present at an appreciable frequency in the general canine population. Further research is needed to determine the clinical significance of these findings.  The phenomenon of somatic genomic alterations in hematopoietic cell lines, commonly referred to as clonal hematopoiesis of indeterminate potential (CHIP) or age-related clonal hematopoiesis (ARCH), has been well characterized in humans and refers to somatic alterations that occur as a result of clonal expansion of the blood system, particularly the white blood cell populations. These alterations tend to be associated with advanced age, often exhibit consistent signal over time, and are frequently found in recurrent locations in the genome ,2,3,4,5.In addition to being a well-documented risk factor for malignancy in humans, CHIP has also been associated with an increased risk for cardiovascular disease   and may Recently, a blood-based liquid biopsy test using next-generation sequencing (NGS) was developed and clinically deployed for cancer detection in dogs. The clinical validation of this test involved 1100 cancer-diagnosed and presumably cancer-free client-owned dogs . The tesMost studies in humans have focused on characterizing single nucleotide variants (SNVs) in particular genes associated with CHIP, but recent reports have shown that CHIP-associated copy number variants (CNVs) are also an important risk factor for the development of leukemia and cardiovascular disease ,5,10. NGThe current study aimed to evaluate the population-level frequency of age-related somatic copy number alterations in the WBC gDNA of dogs and to characterize the type of alterations observed in these patients. Additional studies are currently underway to evaluate the clinical significance of these findings; if successful, these studies could pave the way for broad adoption of CHIP-based testing and monitoring approaches in veterinary medicine that are similar to those already employed for human patients.A total of 4870 client-owned dogs were evaluated as part of this study. Of this total, whole blood samples from 3595 dogs with and without a clinical suspicion of cancer were submitted by the dog’s veterinarian for commercial liquid biopsy testing at the PetDx laboratory in La Jolla, CA ; whole blood samples from 1275 dogs with and without a diagnosis of cancer were obtained as part of a larger research collection to support the clinical validation of the NGS-based liquid biopsy test (“research cohort”) . All resWhole blood samples were collected from each patient; cfDNA was extracted from plasma, and gDNA was extracted from WBCs present in the buffy coat; in the subset of patients with matched tumor tissue available, DNA was also extracted from tissue ,14. All This study focused on a large cohort of canine patients in which specific CNVs were identified in WBC gDNA but were absent in matched cfDNA samples. These findings will be referred to as “WBC gDNA-specific CNVs”, and one example is shown in A subset of dogs with WBC gDNA-specific CNVs had clinical evaluations performed to determine the presence of cancer. Though the components of each evaluation varied, they typically comprised a thorough physical examination, laboratory workup , imaging , and tissue sampling (via fine needle aspiration or biopsy) of observed masses, lesions, and/or enlarged lymph nodes.When the clinical evaluation determined that cancer was present, a definitive or presumptive cancer diagnosis was assigned. “Definitive” diagnoses were those in which cancer was confirmed via tissue-based testing (cytology or histopathology). “Presumptive” diagnoses were based on imaging, direct visualization/exam, or a strong suspicion from cytology or histopathology.p-values were calculated using a two-sided t-test. Analyses were performed using R (version 4.0.5).To compare the age profiles of adult dogs with and without WBC gDNA-specific CNVs, a “normalized age” was calculated relative to expected lifespan, where expected lifespan was calculated as a function of weight according to the equation: lifespan = 13.987 − 0.035 × weight . p-valueThe study population of 4870 client-owned dogs comprised 3595 dogs from the clinical cohort and 1275 dogs from the research cohort .n = 3595) and the average weight was 25.80 kg .In the clinical cohort, cancer status was unknown at the time of sample submission. Samples for 962 dogs were submitted due to a clinical suspicion of cancer (liquid biopsy was used as an aid in diagnosis); samples for 2399 dogs were submitted with no reported suspicion of cancer (liquid biopsy was used as a screening test); and samples for 234 dogs were submitted without documentation regarding cancer suspicion. The average age of dogs in the clinical cohort was 9.09 years  and the average weight was 28.28 kg . A wide range of purebred and mixed-breed dogs were represented in both cohorts.In the research cohort, 569 dogs had a definitive diagnosis of cancer and 706 dogs were presumably cancer-free. The average age of dogs in the research cohort was 7.17 years  dogs in the overall study population: 129 from the clinical cohort and 35 from the research cohort. For 126 of these dogs , CNVs were identified only in the WBC gDNA, and no CNVs of any kind were observed in plasma-derived cfDNA. .Clinical cancer evaluations were performed in 42 of the 126 dogs with WBC gDNA-specific CNVs: 28 from the clinical cohort and 14 from the research cohort.Of the 28 patients in the clinical cohort, 18 had samples submitted with no suspicion of cancer at the time of blood draw . Within this group, 78%  had no evidence of cancer following clinical evaluation, while 22%  received a definitive or presumptive cancer diagnosis. The four cancer diagnoses in the screening patients included: splenic stromal sarcoma , a splenic mass that was suspected to be cancer on imaging but did not have tissue testing for confirmation (presumptive), a hepatic mass (presumptive), and an adrenal gland tumor (presumptive). The remaining 10 out of 28 patients in the clinical cohort had samples submitted for testing due to suspicion of cancer . Within this group, 50%  had no evidence of cancer following clinical evaluation, while 50%  received a definitive or presumptive cancer diagnosis. The 5 cancer diagnoses in the aid-in-diagnosis patients included: histiocytic sarcoma (definitive), a mixed germ cell-sex cord stromal tumor (definitive), two bone tumors (both presumptive), and an adrenal gland tumor (presumptive).All 14 dogs whose samples were submitted as part of the research collection had a definitive diagnosis of cancer at the time of blood collection. The cancer diagnoses in these dogs were as follows: lymphoma/acute lymphoid leukemia (4 cases), osteosarcoma (3 cases), mast cell tumor (2 cases), hemangiosarcoma, anal sac adenocarcinoma, chronic lymphoid leukemia, soft tissue sarcoma, and transitional cell carcinoma. There were 38 dogs with CNVs identified in plasma-derived cfDNA in addition to WBC gDNA-specific CNVs ; 26 of these dogs  had clinical cancer evaluations performed. Among those in the research cohort, all were among the 569 dogs who were enrolled with a definitive diagnosis of cancer. The cancer confirmation rate for these 26 dogs was 100% , demonstrating that observations of somatic CNVs in the plasma cfDNA are highly predictive of concurrent cancer.Tumor tissue samples (from the same collection timepoint as the blood samples with WBC gDNA-specific findings) were available for testing by NGS from 11 of the 35 cancer-diagnosed dogs in the research cohort. The CNVs observed in gDNA were not present in the matched tumor tissue in 91% of cases (10/11). In one case, the same CNVs observed in WBC gDNA were present in matched tissue (from a fine needle aspirate of the left mandibular lymph node); this subject had a definitive diagnosis of T-zone lymphoma (stage IIa).Tumor tissue samples (from the same collection timepoint as the blood samples with cfDNA-specific CNV findings) were available for testing by NGS from 105 cancer-diagnosed dogs in the research cohort. In contrast to WBC gDNA-specific CNVs, the CNVs observed in cfDNA did match the CNVs found in tumor tissue in the vast majority of cases . These results suggest that WBC gDNA-specific CNVs, when present, are typically coincidental  to the patient’s cancer, while cfDNA-specific CNVs are typically derived from the patient’s cancer.Longitudinal blood samples were available for a total of 76 patients with WBC gDNA-specific findings. Seventy-one percent of patients  showed persistence of the gDNA CNVs over time. Several WBC gDNA-specific CNVs were recurrent across patients; the most common CNV was a partial loss of chromosome 25, typically accompanied by a partial gain on the same chromosome a. This pp < 0.0001); in addition, patients with WBC gDNA-specific findings (whether or not they had cancer) were significantly older than the cancer-diagnosed dogs without WBC gDNA-specific CNVs (p < 0.0001). (p = 0.5864).The study cohort was analyzed to evaluate the normalized age of patients with and without WBC gDNA-specific CNVs, and their cancer status. Among patients without WBC gDNA-specific CNVs, dogs with a diagnosis of cancer (definitive or presumptive) were significantly older than dogs who submitted samples as part of the clinical cohort for the purpose of screening and had no evidence of cancer (0.0001).  No signiThe identification of recurrent CNVs in the WBC gDNA of older dogs, which persist with little to no change in amplitude over time and are absent from cfDNA , provides early evidence for the existence of age-related somatic alterations in dogs that resemble the phenomenon of CHIP previously described in humans.Most of the published research on CHIP in humans involves analysis of SNVs ,3; recenIn the current study, analysis was focused on WBC gDNA-specific CNVs in a large cohort of canine patients. Additional studies are underway at PetDx to evaluate the prevalence and distribution of WBC gDNA-specific SNVs in large populations of dogs, as well as the interplay between multiple types of CHIP-associated genomic alterations and clinical outcomes.The clinical significance of age-related somatic alterations in dogs that do not currently have a diagnosis of cancer is uncertain at present and requires further research. The current study found that 22%  of dogs with WBC gDNA-specific findings (in the absence of cfDNA findings) but no initial suspicion of cancer  received a definitive or presumptive diagnosis of cancer following a clinical evaluation. It is unclear how this number compares to the actual prevalence of cancer in an age-matched canine cancer screening population. It will be important to prospectively follow cancer-free dogs with WBC gDNA-specific findings to determine whether they are at higher risk of developing cancer in the future compared to their age-matched counterparts. Long-term monitoring studies are ongoing for patients with WBC gDNA-specific findings identified during clinical testing at PetDx. CHIP in humans is also associated with an increased risk of cardiovascular and potentially cerebrovascular disease ,11,12. IIn addition to the current lack of longitudinal outcome data from patients with WBC gDNA-specific findings, this study faces other limitations.CNVs identified in WBC gDNA have not yet been confirmed to originate from a single hematopoietic cell type, which would substantiate their clonal nature; research is ongoing to elucidate the specific biological source(s) of these findings.Additionally, normalized age calculations were based exclusively on weight for all dogs without consideration of owner-reported breed, which may result in overestimation or underestimation in the case of specific breeds.Lastly, not all dogs had complete medical records and/or clinical evaluations to determine the presence of cancer.The large-scale NGS-based genomic profiling of dogs with and without cancer has uncovered the first potential evidence of age-related somatic copy number alterations in dogs at the population level and is likely to reveal additional novel findings as the use of this type of testing expands. It is not currently known if CHIP-like genomic alterations confer a similar risk of cancer  or other conditions (such as cardiovascular disease) in dogs as they do in humans. Continued research, including long-term clinical monitoring of affected canine patients, will be required for proper clinical interpretation of such findings in the context of liquid biopsy testing in dogs. Such studies have the potential to validate CHIP as an independent risk factor for cancer in dogs and pave the way for the development and clinical adoption of NGS-based CHIP testing and monitoring strategies similar to those now being used in people.


Light-sheet fluorescence microscopy (LSFM), since it was first coined the term selective-plane-illumination microscopy (SPIM) by Huisken et al. , has beeConventional LSFM adopts an orthogonal dual-objective (ODO) configuration, which has the decoupled nature of the geometry in the excitation and collection optical paths, enabling the easy incorporation of many frontier photonics and imaging techniques into a working LSFM , as showThe general approach to improving a light-sheet-based imaging system is using nondiffractive optical beams such as Bessel beam  or strucin vivo. A trite but inevitable issue that comes with it is data storage and processing. It is gratifying that the hybrid OTLS system efficiently decreases the data storage and imaging time via avoid taking tremendous data of the entire region but only the identified ROI. However, 180 GB data set of 24-minute recording as stated in [The work of Glaser et al. is especially attractive given the growing demands of pursuing new biological insights, which often require higher spatiotemporal resolution in ever-larger and intact samples. Owing to the 2D sectioning nature of the light sheet, LSFM is an intrinsic fast imaging technique when the information from a single illuminated plane is simultaneously recorded on 2D array detectors such as CCD or sCMOS cameras. A fast volumetric imaging speed of up to 70 volumes/s has been reported . TogetheAnother consideration that remains for LSFM imaging is the scatter of light in heterogeneous tissue which prevents researchers from achieving high-resolution 3D imaging of thick tissue and puts forward the demand for tissue clearing. All tissue clearing techniques, either solvent-based or aqueous-based, seek transparency through homogenizing the refractive index (RI) of a sample . HoweverFuture innovation aside, the report hybrid OTLS system has taken light-sheet-based imaging techniques to a new level, offering a novel way to obtain high-resolution multiscale optical sectioning detection at fast volumetric imaging speed with low photodamage and phototoxicity.


Most of the research explored the attrition rate and predictive factors for the smartphone application of emotion monitoring in bipolar disorder patients. However, there is less focus on the efficacy of maintaining the retention rate if the incentive system is employed.The aim of our research is to evaluate the efficacy of two different kinds of incentive systems on improving frequency of using the Smartphone Mood Relapse Warning application (MRW-APP)  in bipolar patients.A one-group pretest-posttest pilot study was conducted. Participants with bipolar disorder (n = 63) recorded their moods and symptoms through MRW-APP for 29 weeks with the attrition rate of 44%. Two different kinds of incentive systems, reward and lottery, were implemented. To know whether incentive implementation could play a role in motivating the participants to better adhere to the app, we used Friedman’s test and paired sample t-test to analyze the participants’ app-using frequency in the corresponding weeks.p>.05) before and after we implemented the first incentive system, reward (n=63). For the second incentive system, lottery (n=41), a significant difference in app-using frequency was still not observed (p>.05) after the intervention. But, for those who both had experienced two kinds of incentive systems (n=35), there were significant changes in their app-using frequency (p<.05).There was no significant difference in the participants’ app-using frequency (Image:Image 2:This research found the two incentive systems, award and lottery, may help increase the using frequency of the smartphone monitoring app for participants with bipolar disorder. The results from our study can be a reference for mood monitoring apps development in the future, and it also suggested that incentive system has its potential on encouraging patients’ adherence to e-healthcare.None Declared


Insects are among the planet’s most successful animals. They exist in almost all ecosystems and are therefore exposed to a variety of threats, including extreme weather and climate-related events, nutritional deprivation, pesticide application, pathogen infection, and intra- or inter-species competition . Behavioin vivo models for studying the dynamics of ecological evolution and host-pathogen interactions  and includes important pests and disease vectors. Understanding the molecular and functional bases of the insect olfactory system and how it interacts and coordinates with insect physiology to alter behavior is crucial for devising integrated pest management strategies.Li et al. performed a comprehensive transcriptomic analysis through RNA-sequencing to determine the molecular mechanisms of the olfactory response in different developmental stages of the bean flower thrip, Megalurothrips usitatus . Bioinformatic analysis identified a large set of differentially expressed genes including one odorant-binding protein (MusiOBP1) and one chemosensory protein (MusiCSP1). Obtaining the full-length sequence of MusiOBP1 and MusiCSP1 facilitated their protein expression analysis and purification. Fluorescence binding assays further showed that MusiOBP1 has a strong binding affinity for β-citronellol  while MusiCSP1 strongly binds to 3-hydroxy-2-methyl-4-pvrone . These are important findings with potentially translational applications through developing new behavioral pest control procedures.Kuang et al. investigated antennae-abundant odorant-degrading enzymes in the Asian citrus psyllid, Diaphorina citri . They used a deep sequencing of RNA libraries approach to isolate cytochrome P450 genes from the antennae and body of male and female D. citri. Further qRT-PCR analyses showed that seven antennae-enriched DcCYP genes were antenna-biased and consistently expressed from the first instar to the female and male adult stage. One exception was gene DcCYP6j1, which was expressed at higher levels in male than in the female antennae. These findings will assist in elucidating the D. citri odorant recognition mechanism that will in turn lead to the development of sustainable tactics to restrict the spread of this insect vector.Chen et al. examined the function of odorant receptor genes in the beetle Diorhabda tarsalis . The identification of odorant receptor genes by PacBio RS II platform was followed by phylogenetic analysis, which showed that the odorant coreceptor gene DtarORco was mainly expressed in the antenna of female and male beetles. Successful silencing of DtarORco through RNA interference resulted in reduced electrophysiological responses to host localization odor signals in D. tarsalis which was accompanied by significant impairment of the beetles to detect hosts. This information reveals the key role of DtarORco in behavior and host location, a significant piece of information, that is, required for establishing environmentally friendly control practices for this insect pest.Zhang et al. explored chemoreception in the tea green leafhopper, E. onukii, by focusing on three chemosensory proteins . EonuCSP4, EonuCSP 6-1, and EonuCSP6-2 were expressed at high levels in the antennae of E. onukii and fluorescence binding assays together with behavioral tests indicated that EonuCSP 6-1 had relatively high binding affinity and preference for benzaldehyde. These findings provide strong evidence for the chemoreception properties of EonuCSP 6-1, which may open new avenues for preventing the food-orientation behavior of this pest via obstructing the detection of chemosensory cues.The published papers in this Research Topic present novel information on the functional basis of behavioral adaptations and innate immune responses in various insect species. This knowledge is essential because it contributes to a better understanding of the mechanisms that regulate these fundamental biological adaptation processes in insects . In addi


Hybrid operating rooms (hybrid-ORs) combine the functionalities of a conventional surgical theater with the advanced imaging technologies of a radiological suite. Hybrid-ORs are usually equipped with CBCT devices providing both 2D and 3D imaging capability that can be used for both interventional radiology and image guided surgical applications. Across all fields of surgery, the use of hybrid-ORs is gaining in traction, and neurosurgery is no exception. We hence aimed to comprehensively review the use of hybrid-ORs, the associated advantages, and disadvantages specific to the field of neurosurgery.Electronic databases were searched for all studies on hybrid-ORs from inception to May 2022. Findings of matching studies were pooled to strengthen the current body of evidence.n = 41) and spine surgery (n = 33). Navigation systems were the most common additional technology employed along with the CBCT systems in the hybrid-ORs. Reported advantages of hybrid-ORs included immediate assessment of outcomes, reduced surgical revision rate, and the ability to perform combined open and endovascular procedures, among others. Concerns about increased radiation exposure and procedural time were some of the limitations mentioned.Seventy-four studies were included in this review. Hybrid-ORs were mainly used in endovascular surgery (In the field of neurosurgery, the use of hybrid-ORs for different applications is increasing. Hybrid-ORs provide preprocedure, intraprocedure, and end-of-procedure imaging capabilities, thereby increasing surgical precision, and reducing the need for postoperative imaging and correction surgeries. Despite these advantages, radiation exposure to patient and staff is an important concern.The online version contains supplementary material available at 10.1007/s00701-023-05756-7. A hybrid operating room (hybrid-OR) consists of a conventional surgical theater equipped with advanced imaging systems. The concept of a hybrid-OR was initially described for cardiovascular procedures by Barstad et al. . At firsIntraoperative imaging holds the promise of improved patient care. The ability to visualize anatomical and surgical information in detail can increase surgical accuracy and hence patient safety. With intraoperative imaging, neurosurgeons can acquire updated, and real time, images of the patient in the correct surgical positioning, rather than having to rely on preoperative scans performed in standard positions. In the hybrid-OR, 3D imaging can assist neurosurgeons at different stages of a surgery: preoperatively to visualize the pathology of interest and plan the surgical approach, intraoperatively to provide updated information and assess possible adverse events, and postoperatively for the immediate evaluation of surgical results to allow for corrections when needed. Hybrid-ORs also provide a space where neurosurgeons and interventionalists can collaborate to offer novel treatment options. However, repeated intraoperative imaging and multidisciplinary approaches may interrupt the surgical workflow and unnecessarily complicate procedures . Anotherdate of registration 13 July, 2022). The record was consistently updated in the event of major changes to the workflow or study design.This systematic review is reported in accordance with both the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)  as well A query combining the keywords “hybrid,” “operating room,” “CBCT,” and “neurosurgery” was used to search in PubMed, Web of Science, and Embase   for non-Among the 74 studies included, 59 (80%) were published during the last 5 years (between 2017 and 2022), and 15 (20%) between 2006 and 2016. Overall, the studies originated from 14 different countries, with Europe (50%) and Asia (47%) contributing equally. The remainder of the studies (3%) was from the USA. Only one randomized control trial (1.5%) was identified. In total, there were 26 studies (35%) that presented control or comparison groups  and spine (n = 33). Other areas were represented in eight studies. Several of the studies had addressed more than one area of application, and the presented numbers are non-exclusive. A wide array of procedures was carried out within the hybrid-OR, the most common ones were the treatment of different cerebrovascular pathologies, such as aneurysms (n = 26), AVMs (n = 20), and AVFs (n = 12). Of these, 25 studies reported on combined open and endovascular treatments in the hybrid-OR. Spinal instrumentation procedures were also frequently performed in hybrid-ORs (n = 27). Other procedures included evacuation of brain hemorrhages (n = 6), carotid endarterectomy and stenting (n = 6), and resection of skull base tumors (n = 2). Two studies reported the use of the hybrid-OR only for imaging purposes, while details regarding the procedures were not available in three studies.Hybrid-ORs were mainly employed in two areas of neurosurgery: cerebrovascular including endovascular surgery (n = 37), Artis , UNIQ , INFX-8000 V , Discovery Image-Guided System 730 , and a system manufactured by Toshiba . In six studies, the systems used were undisclosed.The CBCT systems used were mainly the Allura  refers to the acquisition of 3D imaging data during the surgery to obtain updated information. Interventional guidance (n = 33) involves live imaging during an endovascular procedure. Neuronavigation (n = 31) combines 3D imaging data with real-time positional tracking of the patient and surgical instruments. This provides accuracy and allows precise procedures to be performed even when the anatomical structures are unseen such as in minimally invasive procedures. These images were generally obtained at the start of a procedure. However, the hybrid-OR provided the possibility to update the 3D image set used by the navigation software. In two studies, new images were obtained during the procedure.Intraoperative imaging (The use of CBCT for end-of-procedure (EOP) imaging was reported in 56 studies. In these cases, EOP imaging was mainly used to assess surgical result and evaluate the need for adjustments. Three studies stated that EOP imaging in the hybrid-OR was as effective as conventional postoperative imaging for evaluation of surgical results , 44, 52.Forty-four studies reported the use of additional technologies in the hybrid-OR. The use of surgical navigation or surgical robots in spine surgery was reported in 23 studies, the use of indocyanine green video angiography (ICGV) and intraoperative angiography in cerebrovascular surgery in 22 studies, and other technologies including surgical navigation and ultrasound in cranial surgery were reported in four studies.n = 16), a tool for cerebral blood flow assessment. It was performed at the end of the procedure in 13 studies to evaluate the treatment result. A discordance between ICGV investigation and subsequent control angiography was reported in 12 of these studies, with the intraoperative angiography identifying additional residual aneurysms/AVM/fistulas that were not detected by ICGV. Only one study reported complete agreement between ICGV and intraoperative angiography [n = 10). Eight studies used Doppler sonography along with ICGV as routine vascular monitoring at the end of the procedure. Eight studies reported the use of neuronavigation. Brainlab navigation  was used in five and the XperGuide  in one study. One study reported the use of augmented reality for optimal planning of minimally invasive craniotomy [In cerebrovascular surgery, the most commonly used additional medical technology in the hybrid-OR was intraoperative near-infrared indocyanine green video angiography (ICGV) . These included augmented reality surgical navigation (ARSN) , cranial and spine navigation , and the renaissance robotic navigation platform . Two studies combined robotic and ARSN [Surgical navigation systems were often used in the hybrid-OR  as an adjunct in the hybrid-OR. In addition, one study employed ARSN for guidance during cranial biopsy and EVD insertion procedures. One study used ultrasound during ventriculoarterial shunt placement.n = 6), using radiation protection shields (n = 5), or wearing lead aprons (n = 2).Radiation exposure was addressed in 16 studies, but since the data was derived from 14 unique datasets, only 14 studies were considered in this section. Of these 14 studies, ten mentioned at least one occupational radiation protection strategy including keeping a safe distance from the scattered radiation source (the patient) or stepping out of the OR during image acquisition  was compared with a mobile O-arm   significantly reduced radiation exposure when compared to a protocol with higher dose settings (397 projection images per CBCT rotation) during spine instrument implantation . In a thTwo studies compared the radiation exposure to patient  and surgn = 24 studies) was the ability to immediately assess outcomes. Examples included confirmation of safe aneurysm clip positioning, complete obliteration of aneurysm [n = 17) and a reduced need for routine postoperative imaging (n = 5).Sixty-nine studies 93%) discussed the advantages of the hybrid-OR . The possibility of seamless conversion to open surgical access in the event of failure or complication of the endovascular approach, without having to move the patient (n = 10), highlighted the role of hybrid-OR in improving patient safety (n = 10). In fact, rapid detection of complications (n = 4) was one of the advantages raised with the use of a hybrid-OR.The ability to perform combined endovascular and open procedures during a single session and in the same room was an important benefit of a hybrid-OR (n = 4), increased accuracy of the procedure (n = 12), and versatility of the facility as hybrid-ORs can be utilized by a wide array of interventional and surgical disciplines (n = 3).Other advantages of the hybrid-OR that were mentioned include, but are not limited to, improved surgical results (n = 8). Similarly, one study reported the inability to adequately position obese patients in the hybrid-OR, mainly due to the limited gantry size of the C-arm [n = 7). Pitfalls in workflow are mostly immanent to the integration of cumbersome imaging systems into the operating room. Sterility issues (n = 4) and the requirement of a lager surgical space (n = 2) were both commonly mentioned.In total, 37 studies discussed the limitations associated with hybrid-ORs (Table he C-arm . Anothern = 5) due to learning curve on the hybrid equipment is a common concern (n = 4). Although no exact costs were mentioned, higher expenses associated with the installation of a hybrid-OR has been reported (n = 3).Work in a hybrid-ORs requires proper training for the surgeons and the medical staff to attain optimal utilization of the equipment and to optimize the surgical workflow. Prolonged procedure time  has taken place in many surgical specialties, and neurosurgery is no exception. Characterized by smaller incisions and a greater preservation of tissues, MIS inevitably results in limited surgical visibility. This is generally compensated for using intraoperative imaging and navigation technologies. Whether the hybrid-OR provides the platform necessary to sustain the further development of MIS or if MIS will move towards mobile solutions remains to be seen. The publications analyzed in this review should not be taken to directly correspond to the everyday clinical use of the hybrid-OR. Rather, they reflect research interests relating to the technologies and use of the hybrid-OR. As such they may also provide an insight into possible future applications. In this context, it is notable that most of the publications stem from Europe and Asia and only a minority originates in the USA.For cerebrovascular surgery, hybrid-ORs are equipped with high-end angiography systems comparable to those in a conventional angio-suite . This prOne of the most important advantages of the hybrid-OR in the field of cerebrovascular surgery is the ability to perform a combined endovascular and open surgical approach without having to perform time-consuming transfers of the patient between the OR and angiography suite . CombineIn spine surgery, intraoperative imaging can reduce the risk of instrumentation-related neurovascular injury as well as screw misplacement . TraditiThe combination of technologies in the hybrid-OR has been particularly studied in spine surgery. For instance, the ARSN system, specifically developed for the hybrid-OR, uses adhesive markers to create a virtual reference and provides an alternative to conventional tracking systems used for spinal navigation . The incUnfortunately, only a few of the included studies investigated radiation exposure , 51. TheOccupational exposure is reduced by avoiding unnecessary use of radiation, minimizing exposure time, maintaining maximal distance to the scatter source, and using radiation protection shielding . This caWhile hybrid-ORs provide an advantage in procedures where image guidance and navigation are necessary, the scientific literature also includes procedures without a specific need for this technology. Although no extensive cost–benefit analyses have been performed, cost concerns have been previously raised by some authors. Currently, however, hybrid-ORs are mostly found in academic centers and university hospitals, where the additional costs may be accepted in favor of research and technological advances as well as potential long-term benefits. Other concerns with respect to the use of hybrid-ORs that were poorly addressed within the covered literature mainly pertain to the training of staff and the associated learning curves.Hybrid-ORs provide advanced intraoperative imaging capabilities as well as the possibility to combine endovascular and open surgical approaches for the management of complex neurosurgical cases. In this era of rapid technological advances, hybrid-ORs are likely to improve and evolve in terms of workflow, imaging technologies, and auxiliary technologies. This will provide neurosurgeons with the opportunity to treat more challenging cases and contribute to the advancement of minimally invasive, endovascular, and endoscopic approaches. For instance, it has been postulated that the adjunct of augmented reality and robotic techniques may enhance precision and improve patient safety during minimally invasive procedures , 45. SimFurthermore, the hybrid OR may provide an ideal environment for the multidisciplinary aspect of trauma management. Hybrid environments where neurosurgeons, vascular surgeons, and trauma surgeons collaborate with interventional radiologists manage patients with multiple injuries have already been described , 53, 56.Nonetheless, more research is needed to develop protocols and optimize the workflows for different scenarios. It is also important that future work focuses on assessing the impact of hybrid ORs on patient outcomes from both a clinical and a socioeconomic perspective.The main limitation of this review relates to the limitations of the literature itself. The lack of standardized outcome measures makes the results difficult to interpret and compare across studies. Metrics of radiation exposure and doses were rarely standardized, uniform, or consistent among studies, impeding direct quantitative and meta-analytic comparisons or pooling of the published data. Estimating the actual cost-effectiveness of a hybrid-OR could not be achieved, as this information was nearly non-existent. Other poorly addressed concerns regarding the use of hybrid-ORs mainly pertain to the training of staff and the associated learning curves. Due to the lack of objective metrics, addressing the effects of the learning curves associated with the introduction of hybrid-ORs was not possible. The learning curves depend on the complexity and degree of integration of new technologies in the hybrid-OR, on the previous training of the staff and the number of cases available for staff training, making this parameter difficult to evaluate. Albeit challenging, a thorough analysis of this aspect is important to justify the increasing use of hybrid-ORs. Furthermore, only a few studies compared hybrid-ORs to more conventional ORs. Randomized control trials to evaluate the efficacy and safety of hybrid-ORs are needed, as are studies aimed at determining which procedures and what patient categories benefit the most from treatment in hybrid-ORs. In fact, one study reached the conclusion that the hybrid-OR was only crucial to 2% of cerebrovascular procedures . A studyHybrid-ORs, equipped with CBCT and angiography, are increasingly used in the context of both vascular and spinal neurosurgery. They provide preprocedure, intraprocedure, and end-of-procedure imaging capabilities, thereby increasing the surgical precision, and reducing the need for postoperative imaging and correction surgeries. Despite these advantages, prolonged operative durations and radiation exposure to patient and staff are important concerns. However, protective measures may result in reduced exposure for both patient and staff compared to conventional solutions. Hybrid-ORs offer possibilities in the development of new minimally invasive surgical approaches, but the costs of installation and equipment acquisition limit their current use to large centers. Given the lack of randomized, controlled studies objectively evaluating the superiority of hybrid-ORs, the current state of the literature indicates that the use of hybrid ORs in neurosurgery is still in an experimental and developmental phase.Supplementary file1 (DOCX 128 KB)Supplementary file2 (PDF 128 KB)Supplementary file3 (DOCX 79 KB)Supplementary file4 (DOCX 453 KB)Supplementary file5 (DOCX 111 KB)Below is the link to the electronic supplementary material.


Psychophysical diseases can be cured without medical intervention, and this is the so-called self-healing. Self-healing is the process of recovery from emotional ill-health, but self-healing can also include accompanying physical health issues. Cognitive-behavioral therapy is one of the effective methods that help the individual to activate their role in self-healing and controlling thoughts and lifestyle. Being therapeutically effective in previous literature and less expensive than medication, CBT can be utilized by psychiatry practitioners.The current study aimed at investigating the effects of a cognitive behavioral therapy-based program to promote self-healing of patients with irritable bowel syndrome (IBS). Additionally, it explores the continuity of the proposed program effectiveness throughout six months.The quasi-experimental method (one group design) was adopted Participants were 4 patients (ages between 29-34 years) were purposively selected since they were suffering from irritable bowel syndrome (IBS) for (4-11) years based on the diagnosis conducted by Gastroenterology Clinic specialists at Sultan Qaboos Hospital in Salalah. The fifteen sessions of the therapeutic intervention lasted for five weeks. No medications were taken during the intervention and the follow-up period.Results indicated the effectiveness of the intervention in promoting self-healing of the irritable bowel syndrome (IBS) and a decrease in the symptoms of the irritable bowel in the medical examination after intervention as shown in the significant differences between time 1 and time 2 assessment while no significant difference was detected between time 2 and time 3 assessment (follow-up). A significant decrease in the medical symptoms of IBS (85% improvement rate).Non-pharmacological psychotherapy is beneficial with patients with psychosomatic disorders as it can be used effectively to improve self-healing.None Declared


Brunner syndrome is a recessive X-linked disorder characterized by impulsive aggressiveness and mild mental retardation associated with Monoamine Oxidase – A (MAOA) deficiency .To present a REM sleep behavior disorder (RBD) case in a patient with Brunner syndrome.The present study is a case report of a patient followed in our hospital’s outpatient care. We also searched for previous case reports of sleep disorders and other clinical features in Brunner syndrome using a pubmed query.A 46-year-old Spanish male, diagnosed with Brunner syndrome due to the mutation c.1438A>G/iVS14-2 A>G, a loss-of-function mutation in the X-linked MAOA gene. He suffers from mild mental retardation and psychotic disturbances treated with SSRI and antipsychotic drugs. The patient was referred to our outpatient care to assess his sleep abnormal behaviors. He had been presenting with episodes of sleep-related vocalization and complex motor behaviors during sleep for the last 3 years, correlating with dream mentation. His relatives recounted episodes of talking, screaming, gesturing, kicking, falling out of bed and crying during sleep. Dream content referred by the patient was often related to persecutions, attacks and fights.Polysomnography revealed vocalization and gesticulation during REM sleep compatible with the diagnosis of RBD. The addition of clonazepam to his treatment at doses of 1-3 mg per day achieved significant clinical response of the sleep disorder.The clinical presentation suggested the diagnosis of RBD case in a patient with Brunner syndrome. Although sleep disorders are not one of the most important or frequent clinical features in Brunner syndrome, they are described in the literature and can significantly affect the patient’s quality of life. To our knowledge, this is the first report about clinical management of RBD case in Brunner syndrome.None Declared


SPC-c-Raf-1-BxB transgenic mice develop genetically induced disseminated lung adenocarcinoma allowing examination of carcinogenesis and evaluation of novel treatment strategies. We report on assessment of lung tumour growth kinetics using a semiautomated region growing segmentation algorithm.156 non contrast-enhanced respiratory gated micro-CT of the lungs were obtained in 12 SPC-raf transgenic (n = 9) and normal (n = 3) mice at different time points. Region-growing segmentation of the aerated lung areas was obtained as an inverse surrogate for tumour burden. Time course of segmentation volumes was assessed to demonstrate the potential of the method for follow-up studies.p = 0.009). Significant group differences could be detected between transgenic and normal animals for time points 8 to 13 months (p = 0.043), when marked tumour progression occurred.Micro-CT allowed assessment of tumour growth kinetics and semiautomated region growing enabled quantitative analysis. Significant changes of the segmented lung volumes over time could be shown (The presented region-growing segmentation algorithm allows in-vivo quantification of multifocal lung adenocarcinoma in SPC-raf transgenic mice. This enables the assessment of tumour load and progress for the study of carcinogenesis and the evaluation of novel treatment strategies. A number of genetic animal models of lung cancer has been developed to better understand the molecular causes of this disease. In-vivo imaging in these disease models can allow a better understanding of biological processes and a time-course assessment of therapeutic approaches. We here report on longitudinal in-vivo micro-CT measurements of lung tumour in a transgenic mouse model of lung cancer.The animal model examined has been reported in the literature already -5. In thThis animal model allows probing for mechanisms of carcinogenesis based on a genetic cascade that also plays a crucial role in the development of adenocarcinoma of the lungs in humans. Furthermore, it offers the opportunity to study carcinogenesis in a more realistic setting as compared to models of implanted (xenograft) tumours into immunodeficient mice. In fact, the animals are still immunologically competent, while the continuous expression of the transgene secures continuous tumour pressure. Thus, the relevance of overexpressed protooncogenes or disabled tumour suppressor genes can be studied.Different imaging modalities have been reported and their advantages and disadvantages have been evaluated for imaging of murine lung pathology. Comparatively fast assessment of morphology can be obtained using micro-CT . FurtherIn this study we report on the use of a micro-CT quantification algorithm for the longitudinal assessment of tumor progression in SPC-raf transgenic mice.12 mice (SPC-raf transgenic n = 9 and wildtype n = 3) were examined (Table In-vivo micro-CT imaging was first performed at the age of 2 months (day 55 to day 61) and repeated every 4 weeks. Follow-up examinations were repetitively carried out until the animal had to be euthanized due to medical condition or termination of the study. The follow-up had to be terminated on day 146 in one animal, in the other animals between day 362 and 547. A total of 156 CT exams were carried out in this study.Isoflurane inhalation anaesthesia was administered using a nose cone. The animals were placed in prone position on a multimodality bed that enables changes between the different imaging modalities without repositioning. A pressure transducer pad was placed under the animal's chest for respiratory monitoring, which was used for respiratory gating and for control of anaesthesia.Non contrast-enhanced prospectively respiratory gated micro-CT was performed  with an effective pixel size of 0.094 mm . The scan FOV was 32.8 mm. For respiratory gating the signal from the transducer pad was used to generate the image acquisition time points using the software Biovet . Images of the chest were reconstructed and calibrated to the Hounsfield scale. Expected mean radiation dose was calculated to be 197 mGy based on phantom and cadaver measurements in a previous study [®  and subsequently fixed in 4% buffered formalin (pH 7.2). After dehydration  lungs were embedded in paraffin. Sections (2 μm thick) were deparaffinized with xylene and H&E stained.The imaging findings were correlated to necropsy and histology in 10 cases  by direct visual comparison. In two animals no histology was obtained. At necropsy lung surface was assessed for tumour affection and correlated to imaging. After necropsy the excised lungs were filled with Tissue-Tek O.C.T.For quantification of the multifocal tumours a segmentation of the aerated parts of the lungs was used as a surrogate parameter, as direct measurement was not feasible. A region-growing algorithm for micro-CT quantification of tumour load and progress for diffuse lung adenocarcinoma was established and validated earlier . The opeP < 0.05 was considered as statistical significant.Statistical analysis was performed using IBM SPSS Statistics 19 . A repeated measurement analysis was performed. Due to the limited number of animals the number of time points analysed had to be reduced. Analysis was performed for time points 2, 4, 6, 7-13 months. Due to a limited number of measurements one animal had to be excluded from the statistical analysis . Furthermore a linear regression analysis was performed and the correlation coefficient was calculated. No adverse events occurred due to the imaging procedures or anesthesia. Image quality was good in most cases and acceptable in all cases.In this follow-up study progressive tumour burden could be seen in SPC-raf transgenic mice, while no obvious changes were noted in the control group Figure  and 4. VThe region growing segmentation using the described post-processing algorithm could be performed in all cases. In the evaluation study repositioning of seed points due to overspilling of the segmentation volume into adjacent structures was not necessary using the same algorithm for 90 segmentations , in thisIn the comparatively small group examined here, tumour growth seemed to occur at a later point of time in male animals as compared to female animals. Female animals showed clinical signs of tumour necessitating sacrifice earlier compared to male animals.p = 0.009). Interaction of the measurements was rejected (p = 0.035). Testing for group differences did not show significant results, due to the small number of animals and the spread of lung volume at early time points in normal animals. Analysis of time points 8 to 13 months, when tumour progression occurs, showed significant group differences (p = 0.043). Linear regression analysis yielded equation 1 to calculate lung volume. The correlation coefficient was determined as R = 0.538.Repeated measurement analysis of the time points 2, 4, 6, 7-13 months showed significant changes of the segmented lung volumes over time  -14. OtheAll the various imaging approaches of murine animal models of human lung tumour have different advantages and disadvantages. Some animal models are highly artificial with regard to the mechanism of carcinogenesis or the immunological competence of the tumour bearing organism. But they may provide imaging characteristics similar to the situation in humans with a single comparatively well-defined lesion. The multifocal tumour growth in the SPC-raf transgenic animal model examined in this study limits direct application of established radiological imaging techniques in humans. However, it has already been reported that this animal model allows examination of the potential relevance of human protooncogenes or disabled tumour suppressor genes in an immunologically competent environment. Thus, aspects of human carcinogenesis may be better understood highlighting the clinically translational aspects of the research.In the animals examined in this study tumour growth seemed to occur at a later point of time in male animals as compared to female animals, furthermore females showed clinical signs of tumour necessitating to sacrifice the animals earlier compared to male animals (Table1). This has not been reported for the SPC-raf transgenic animal model, yet. However, due to the genetic mechanism of tumour induction in this model it might represent a relevant finding to understand lung tumour carcinogenesis. Further experiments have to be performed in order to validate the potential finding and present a hypothesis for the origin. The primary focus of this study was to demonstrate the use of micro-CT for assessment of tumour load and growth. The issue demonstrates the potential additional benefit of the method for assessment of cofactors affecting carcinogenesis applying intraindividual time-course assessment.Micro-CT imaging applying the setup described above did not result in adverse events, even though animals had advanced tumour stages at the later time points. In synopsis with other studies performed we attribute this to the use of isoflurane inhalation anaesthesia, respiratory monitoring and the use of a heating blanket. We performed prospective respiratory gating as it has been reported to significantly increase image quality. However, more sophisticated gating techniques such as retrospective or intrinsic gating or high-speed single-breath hold techniques could further optimize imaging -22. MRI 50/30  of 7.52 Gy demonstrate the relevance of the issue [Dose measurements for the applied micro-CT protocol were performed in a phantom and ex-vivo in previous studies. The effective dose calculated from these measurements was 154 mGy for the selected protocol. An additional radiation dose has to be added for planning the scan-area under fluoroscopy. For this a dose of 19 mGy/min was measured, resulting in 202 mGy/scan . Animalshe issue . Howeverhe issue  structurhe issue  and the he issue .In conclusion the presented region-growing segmentation algorithm allows longitudinal in-vivo quantification of multifocal lung adenocarcinoma in SPC-raf transgenic mice. This enables the assessment of tumor load and growth kinetics for the study of carcinogenesis and the evaluation of novel treatment strategies.There are no financial or non-financial competing interests to declare in relation to this manuscript by any of authors.TR designed the study, contributed to performing the experiments and wrote the manuscript. CvF, SD, and RH participated in acquisition of the imaging data and contributed to drafting the manuscript. ML performed radiation dose analysis, furthermore he was involved in drafting the manuscript. LH performed statistical analysis and was involved in drafting the manuscript. JB and FW contributed to study design, data analysis and revised the manuscript critically. All authors read and approved the final manuscript.