Gut microbial metabolite trimethylamine N-oxide induces aortic dissection.

Aortic dissection (AD) is the most catastrophic vascular disease with a high mortality rate. Trimethylamine N-oxide (TMAO), a gut microbial metabolite, has been implicated in the pathogenesis of cardiovascular diseases. However, the role of TMAO in AD and the underlying mechanisms remain unclear. This study aimed to explore the effects of TMAO on AD. Plasma and fecal samples from patients with AD and healthy individuals were collected to analyze TMAO levels and gut microbial species, respectively. The plasma levels of TMAO were significantly higher in 253 AD patients compared with those in 98 healthy subjects (3.47, interquartile range (IQR): 2.33 to 5.18 µM vs. 1.85, IQR: 1.40 to 3.35 µM; p < 0.001). High plasma TMAO levels were positively associated with AD severity. An increase in the relative abundance of TMA-producing genera in patients with AD was revealed using 16S rRNA sequencing. In the angiotensin II or ß-aminopropionitrile-induced rodent model of AD, mice fed a TMAO-supplemented diet were more likely to develop AD compared to mice fed a normal diet. Conversely, TMAO depletion mitigated AD formation in the BAPN model. RNA sequencing of aortic endothelial cells isolated from mice administered TMAO revealed significant upregulation of genes involved in inflammatory pathways. The in vitro experiments verified that TMAO promotes endothelial dysfunction and activates nuclear factor (NF)-κB signaling. The in vivo BAPN-induced AD model confirmed that TMAO increased aortic inflammation. Our study demonstrates that the gut microbial metabolite TMAO aggravates the development of AD at least in part by inducing endothelial dysfunction and inflammation. This study provides new insights into the etiology of AD and ideas for its management.

Visualizing Large Facet-Dependent Electronic Tuning in Monolayer WSe2 on Au Surfaces.

Two-dimensional transition metal dichalcogenides (TMDs) have shown great importance in the development of novel ultrathin optoelectronic devices owing to their exceptional electronic and photonic properties. Effectively tuning their electronic band structures is not only desired in electronics applications but also can facilitate more novel properties. In this work, we demonstrate that large electronic tuning on a WSe2 monolayer can be realized by different facets of a Au-foil substrate, forming in-plane p-n junctions with remarkable built-in electric fields. This facet-dependent tuning effect is directly visualized by using scanning tunneling microscopy and differential conductance (dI/dV) spectroscopy. First-principles calculations reveal that the atomic arrangement of the Au facet effectively changes the interfacial coupling and charge transfer, leading to different magnitudes of charge doping in WSe2. Our study would be beneficial for future customized fabrication of TMD-junction devices via facet-specific construction on the substrate.

Novel aggrecan variant, p. Gln2364Pro, causes severe familial nonsyndromic adult short stature and poor growth hormone response in Chinese children.

BACKGROUND: Mutations in the aggrecan (ACAN) gene can cause short stature (with heterogeneous clinical phenotypes), impaired bone maturation, and large variations in response to growth hormone (GH) treatment. For such cases, long-term longitudinal therapy data from China are still scarce. We report that a previously unknown ACAN gene variant reduces adult height and we analyze the GH response in children from an affected large Chinese family. METHODS: Two children initially diagnosed with idiopathic short stature (ISS) and a third mildly short child from a large Chinese family presented with poor GH response. Genetic etiology was identified by whole exome sequencing and confirmed via Sanger sequencing. Adult heights were analyzed, and the responses to GH treatment of the proband and two affected relatives are summarized and compared to other cases reported in the literature. RESULTS: A novel ACAN gene variant c.7465 T > C (p. Gln2364Pro), predicted to be disease causing, was discovered in the children, without evident syndromic short stature; mild bone abnormity was present in these children, including cervical-vertebral clefts and apophyses in the upper and lower thoracic vertebrae. Among the variant carriers, the average adult male and female heights were reduced by - 5.2 and - 3.9 standard deviation scores (SDS), respectively. After GH treatment of the three children, first-year heights increased from 0.23 to 0.33 SDS (cases in the literature: - 0.5 to 0.8 SDS), and the average yearly height improvement was 0.0 to 0.26 SDS (cases in the literature: - 0.5 to 0.9 SDS). CONCLUSIONS: We report a novel pathogenic ACAN variant in a large Chinese family which can cause severe adult nonsyndromic short stature without evident family history of bone disease. The evaluated cases and the reports from the literature reveal a general trend of gradually diminishing yearly height growth (measured in SDS) over the course of GH treatment in variant-carrying children, highlighting the need to develop novel management regimens.

[Trace Carbon Monoxide Detection with a Cavity Ring-Down Spectrometer].

A cavity ring-down spectrometer (CRDS) was built based on telecom distributed feedback (DFB) diode lasers. The ring down cavity was formed by mirrors of 99. 997% reflectivity with a separation of 130 cm, with an empty ring down time of about 150 µs. A minimum detectable absorption coefficient of 5 x 10(-12) cm(-1) was obtained by averaging about 1,000 recorded spectra. The ring down cavity is thermo-isolated, and used as an interferometer to calibrate the recorded spectrum. A feedback control scheme was applied to step scan the laser frequency, successively matching each of the longitudinal modes of the cavity. By measuring the CO contents in a standard gas sample, the quantitative capability of the CRDS instrument was demonstrated, and a CO detection limit of 4 ppb was achieved. The instrument was applied to monitor the CO concentration in ambient air.

Ultrasensitive, self-calibrated cavity ring-down spectrometer for quantitative trace gas analysis.

A cavity ring-down spectrometer is built for trace gas detection using telecom distributed feedback (DFB) diode lasers. The longitudinal modes of the ring-down cavity are used as frequency markers without active-locking either the laser or the high-finesse cavity. A control scheme is applied to scan the DFB laser frequency, matching the cavity modes one by one in sequence and resulting in a correct index at each recorded spectral data point, which allows us to calibrate the spectrum with a relative frequency precision of 0.06 MHz. Besides the frequency precision of the spectrometer, a sensitivity (noise-equivalent absorption) of 4×10-11 cm-1 Hz-1/2 has also been demonstrated. A minimum detectable absorption coefficient of 5×10-12 cm-1 has been obtained by averaging about 100 spectra recorded in 2  h. The quantitative accuracy is tested by measuring the CO2 concentrations in N2 samples prepared by the gravimetric method, and the relative deviation is less than 0.3%. The trace detection capability is demonstrated by detecting CO2 of ppbv-level concentrations in a high-purity nitrogen gas sample. Simple structure, high sensitivity, and good accuracy make the instrument very suitable for quantitative trace gas analysis.

Label-Free Optical Technologies for Middle-Ear Diseases.

Medical applications of optical technology have increased tremendously in recent decades. Label-free techniques have the unique advantage of investigating biological samples in vivo without introducing exogenous agents. This is especially beneficial for a rapid clinical translation as it reduces the need for toxicity studies and regulatory approval for exogenous labels. Emerging applications have utilized label-free optical technology for screening, diagnosis, and surgical guidance. Advancements in detection technology and rapid improvements in artificial intelligence have expedited the clinical implementation of some optical technologies. Among numerous biomedical application areas, middle-ear disease is a unique space where label-free technology has great potential. The middle ear has a unique anatomical location that can be accessed through a dark channel, the external auditory canal; it can be sampled through a tympanic membrane of approximately 100 microns in thickness. The tympanic membrane is the only membrane in the body that is surrounded by air on both sides, under normal conditions. Despite these favorable characteristics, current examination modalities for middle-ear space utilize century-old technology such as white-light otoscopy. This paper reviews existing label-free imaging technologies and their current progress in visualizing middle-ear diseases. We discuss potential opportunities, barriers, and practical considerations when transitioning label-free technology to clinical applications.

Getting what you pay for: impact of copayments on physical therapy and opioid initiation, timing, and continuation for newly diagnosed low back pain.

BACKGROUND CONTEXT: Physical therapy (PT) is an important component of low back pain (LBP) management. Despite established guidelines, heterogeneity in medical management remains common. PURPOSE: We sought to understand how copayments impact timing and utilization of PT in newly diagnosed LBP. STUDY DESIGN/SETTING: The IBM Watson Health MarketScan claims database was used in a longitudinal setting. PATIENT SAMPLE: Adult patients with LBP. OUTCOME MEASURES: The primary outcomes-of-interest were timing and overall utilization of PT services. Additional outcomes-of-interest included timing of opioid prescribing. METHODS: Actual and inferred copayments based on nonnonprimary care provider visit claims were used to evaluate the relationship between PT copayment and incidence of PT initiation. Multivariable regression models were used to evaluate factors influencing PT usage. RESULTS: Overall, 2,467,389 patients were included. PT initiation, among those with at ≥1 PT service during the year after LBP diagnosis (30.6%), occurred at a median of 8 days postdiagnosis (IQR 1-55). Among those with at least one PT encounter, incidence of subsequent PT visits was significantly lower for those with high initial PT copayments. High initial PT copayments, while inversely correlated with PT utilization, were directly correlated with subsequent opioid use (0.77 prescriptions/patient [$0 PT copayment] versus 1.07 prescriptions/patient [$50-74 PT copayment]; 1.15 prescriptions/patient [$75+ PT copayment]). Among patients with known opioid and PT copayments, higher PT copayments were correlated with faster opioid use while higher opioid copayments were correlated with faster PT use (Spearman p<.05). For multivariable whole-cohort analyses, incidence of PT initiation among patients with inferred copayments in the 50-75th and 75-100th percentiles was significantly lower than those below the 50th percentile (HR=0.893 [95%CI 0.887-0.899] and HR=0.905 [95%CI 0.899-0.912], respectively). CONCLUSIONS: Higher PT copayments correlated with reduced PT utilization; higher PT copayments and lower opioid copayments were independent contributors to delayed PT initiation and higher opioid use. In patients covered by plans charging high PT copayments, opioid use was significantly higher. Copays may impact long-term adherence to PT.

A machine learning approach for predicting descending thoracic aortic diameter.

Background: To establish models for predicting descending thoracic aortic diameters and provide evidence for selecting the size of the stent graft for TBAD patients. Methods: A total of 200 candidates without severe deformation of aorta were included. CTA information was collected and 3D reconstructed. In the reconstructed CTA, a total of 12 cross-sections of peripheral vessels were made perpendicular to the axis of flow of the aorta. Parameters of the cross sections and basic clinical characteristics were used for prediction. The data was randomly split into the training set and the test set in an 8:2 ratio. To fully describe diameters of descending thoracic aorta, three predicted points were set based quadrisection, and a total of 12 models at three predicted points were established using four algorithms included linear regression (LR), support vector machine (SVM), Extra-Tree regression (ETR) and random forest regression (RFR). The performance of models was evaluated by mean square error (MSE) of the prediction value, and the ranking of feature importance was given by Shapley value. After modeling, prognosis of five TEVAR cases and stent oversizing were compared. Results: We identified a series of parameters which affect the diameter of descending thoracic aorta, including age, hypertension, the area of proximal edge of superior mesenteric artery, etc. Among four predictive models, all the MSEs of SVM models at three different predicted position were less than 2 mm2, with approximately 90% predicted diameters error less than 2 mm in the test sets. In patients with dSINE, stent oversizing was about 3 mm, while only 1 mm in patients without complications. Conclusion: The predictive models established by machine learning revealed the relationship between basic characteristics and diameters of different segment of descending aorta, which help to provide evidence for selecting the matching distal size of the stent for TBAD patients, thereby reducing the incidence of TEVAR complications.

Opioid Usage in Lumbar Disc Herniation Patients with Nonsurgical, Early Surgical, and Late Surgical Treatments.

OBJECTIVE: To assess opioid usage in surgical and nonsurgical patients with lumbar disc herniation receiving different treatments and timing of treatments. METHODS: Individuals with newly diagnosed lumbar intervertebral disc herniation without myelopathy were queried from a health claims database. Patients were categorized into 3 cohorts: nonsurgical, early surgery, and late surgery. Early surgery cohort patients underwent surgery within 30 days postdiagnosis; late surgery cohort patients had surgery after 30 days but before 1 year postdiagnosis. The index date was defined as the diagnosis date for nonsurgical patients and the initial surgery date for surgical patients. The primary outcome was the average daily opioid morphine milligram equivalents (MME) prescribed. Additional outcomes included percentage of opioid-using patients and cumulative opioid burden. RESULTS: Inclusion criteria were met by 573,082 patients: 533,226 patients received nonsurgical treatments, 22,312 patients received early surgery, and 17,544 patients received late surgery. Both surgical cohorts experienced a postsurgical increase in opioid usage, which then sharply declined and gradually plateaued, with daily opioid MME consistently lower in the early versus late surgery cohort. The early surgery cohort also consistently had a lower prevalence of opioid-using patients than the late surgery cohort. Patients receiving nonsurgical treatment demonstrated the highest 1-year post index cumulative opioid burden, and the early surgery cohort consistently had lower cumulative opioid MME than the late surgery cohort. CONCLUSIONS: Early surgery in patients with lumbar disc herniation is associated with lower long-term average daily MME, incidence of opioid use, and 1-year cumulative MME burden compared with nonsurgical and late surgery treatment approaches.

Fibroblast-Secreted Phosphoprotein 1 Mediates Extracellular Matrix Deposition and Inhibits Smooth Muscle Cell Contractility in Marfan Syndrome Aortic Aneurysm.

Fibrillin 1 (Fbn1) mutation causes Marfan syndrome (MFS) with thoracic aortic aneurysm (TAA) as the main complication. The mechanisms for extracellular matrix (ECM) homeostasis disruption in MFS TAA are unclear. Here, we found ECM-related gene secreted phosphoprotein 1 (Spp1) increased in Fbn1C1041G/+ mice using transcriptome sequencing and a distinct fibroblast subcluster with Spp1 as the strongest marker was identified with analysis of the MFS mouse aortic single-cell sequencing dataset. Immunostaining confirmed elevated Spp1 in adventitial fibroblasts, and Spp1 might regulate fibroblast and smooth muscle cell (SMC) communication primarily through Itga8/Itgb1. Then, we observed Spp1 reduced contractile genes Acta2 and Tagln expression in SMCs and increased collagen expression in fibroblasts, which might contribute to TAA development. Finally, we also found elevated SPP1 plasma level was associated with an increased risk of TAA in patients. Therefore, SPP1 may serve as a biomarker and therapeutic target for TAA.

Health Care Resource Utilization in Management of Opioid-Naive Patients With Newly Diagnosed Neck Pain.

Importance: Research has uncovered heterogeneity and inefficiencies in the management of idiopathic low back pain, but few studies have examined longitudinal care patterns following newly diagnosed neck pain. Objective: To understand health care utilization in patients with new-onset idiopathic neck pain. Design, Setting, and Participants: This cross-sectional study used nationally sourced longitudinal data from the IBM Watson Health MarketScan claims database (2007-2016). Participants included adult patients with newly diagnosed neck pain, no recent opioid use, and at least 1 year of continuous postdiagnosis follow-up. Exclusion criteria included prior or concomitant diagnosis of traumatic cervical disc dislocation, vertebral fractures, myelopathy, and/or cancer. Only patients with at least 1 year of prediagnosis lookback were included. Data analysis was performed from January 2021 to January 2022. Main Outcomes and Measures: The primary outcome of interest was 1-year postdiagnosis health care expenditures, including costs, opioid use, and health care service utilization. Early services were those received within 30 days of diagnosis. Multivariable regression models and regression-adjusted statistics were used. Results: In total, 679 030 patients (310 665 men [45.6%]) met the inclusion criteria, of whom 7858 (1.2%) underwent surgery within 1 year of diagnosis. The mean (SD) age was 44.62 (14.87) years among nonsurgical patients and 49.69 (9.53) years among surgical patients. Adjusting for demographics and comorbidities, 1-year regression-adjusted health care costs were $24 267.55 per surgical patient and $515.69 per nonsurgical patient. Across all health care services, $95 379 949 was accounted for by nonsurgical patients undergoing early imaging who did not receive any additional conservative therapy or epidural steroid injections, for a mean (SD) of $477.53 ($1375.60) per patient and median (IQR) of $120.60 ($20.70-$452.37) per patient. On average, patients not undergoing surgery, physical therapy, chiropractic manipulative therapy, or epidural steroid injection, who underwent either early advanced imaging (magnetic resonance imaging or computed tomography) or both early advanced and radiographic imaging, accumulated significantly elevated health care costs ($850.69 and $1181.67, respectively). Early conservative therapy was independently associated with 24.8% (95% CI, 23.5%-26.2%) lower health care costs. Conclusions and Relevance: In this cross-sectional study, early imaging without subsequent intervention was associated with significantly increased health care spending among patients with newly diagnosed idiopathic neck pain. Early conservative therapy was associated with lower costs, even with increased frequency of therapeutic services, and may have reduced long-term care inefficiency.

Excessive DNA damage mediates ECM degradation via the RBBP8/NOTCH1 pathway in sporadic aortic dissection.

Stanford type A aortic dissection (TA-AD) is a life-threatening disease. Most cases of aortic dissection (AD) are sporadic rather than inherited. Unlike that of inherited AD, the pathogenesis of sporadic AD is still unclear. In the current study, we aimed to explore the pathogenesis of sporadic AD through transcriptome sequencing data analyses. We downloaded sporadic TA-AD transcriptome profiles from Gene Expression Omnibus (GEO) and found response to DNA damage stimulus was activated in AD. Furthermore, by conducting mouse AD tissue single cell RNA sequencing and immunostaining, we found that DNA damage mainly occurred in smooth muscle cells (SMCs) and fibroblasts. Next, we examined the repair patterns in response to DNA damage and found the linker molecules RBBP8/NOTCH1 between DNA damage/repair and extracellular matrix (ECM) organization through protein-protein interaction analysis. Thus, we proposed that DNA damage could contribute to AD by regulating ECM changes. To explore the underlying mechanism, we knocked down the DNA repair-related gene RBBP8 in aortic SMCs, which could exacerbate DNA damage, and observed decreased expression level of NOTCH1. Inhibition of NOTCH1 with crenigacestat in vivo accelerated ß-aminopropionitrile-induced formation of AD and increased mortality. Meanwhile, phenotype switching of SMCs was induced by Notch1 knockdown or inhibition; this switching occurred via a pathway involving downregulation of contractile marker gene expression and upregulation of MMP2 expression, which might aggravate ECM degradation. In conclusion, excessive DNA damage is a characteristic pathological change of sporadic aortic dissection, which might contribute to ECM changes and AD development via action on the NOTCH1 pathway.

Identification of pathological-related and diagnostic potential circular RNAs in Stanford type A aortic dissection.

Introduction: Stanford type A aortic dissection (TAAD) is one of the lethal macrovascular diseases caused by the invasion of blood into the media layer of ascending aortic wall. Inflammation, smooth muscle dysfunction, and extracellular matrix (ECM) degradation were regarded as the major pathology in affected tissue. However, the expression pattern and its regulation especially through circular RNAs (circRNAs) as an overall characteristic of TAAD molecular pathology remain unclear. Methods: We employed CIRCexplorer2 to identify circRNAs based on the RNA sequencing (RNA-seq) data of human ascending aortic tissues to systematically assess the role of circRNA in the massive alterations of gene expression in TAAD aortas. The key circRNAs were determined by LASSO model and functionally annotated by competing endogenous RNAs (ceRNA) network and co-analysis with mRNA profile. The expression level and diagnostic capability of the 4 key circRNAs in peripheral serum were confirmed by real-time polymerase chain reaction (RT-PCR). Results: The 4 key circRNAs, namely circPTGR1 (chr9:114341075-114348445[-]), circNOX4 (chr11:89069012-89106660[-]), circAMN1 (chr12:31854796-31862359[-]) and circUSP3 (chr15:63845913-63855207[+]), demonstrated a high power to discriminate between TAAD and control tissues, suggesting that these molecules stand for a major difference between the tissues at gene regulation level. Functionally, the ceRNA network of circRNA-miRNA-mRNA predicted by the online databases, combining gene set enrichment analysis (GSEA) and cell component prediction, revealed that the identified circRNAs covered all the aspects of primary TAAD pathology, centralized with increasing inflammatory factors and cells, and ECM destruction and loss of vascular inherent cells along with the circRNAs. Importantly, we validated the high concentration and diagnostic capability of the 4 key circRNAs in the peripheral serum in TAAD patients. Discussion: This study reinforces the vital status of circRNAs in TAAD and the possibility of serving as promising diagnostic biomarkers.

Species- and site-specific genome editing in complex bacterial communities.

Understanding microbial gene functions relies on the application of experimental genetics in cultured microorganisms. However, the vast majority of bacteria and archaea remain uncultured, precluding the application of traditional genetic methods to these organisms and their interactions. Here, we characterize and validate a generalizable strategy for editing the genomes of specific organisms in microbial communities. We apply environmental transformation sequencing (ET-seq), in which nontargeted transposon insertions are mapped and quantified following delivery to a microbial community, to identify genetically tractable constituents. Next, DNA-editing all-in-one RNA-guided CRISPR-Cas transposase (DART) systems for targeted DNA insertion into organisms identified as tractable by ET-seq are used to enable organism- and locus-specific genetic manipulation in a community context. Using a combination of ET-seq and DART in soil and infant gut microbiota, we conduct species- and site-specific edits in several bacteria, measure gene fitness in a nonmodel bacterium and enrich targeted species. These tools enable editing of microbial communities for understanding and control.

Exaggerated Autophagy in Stanford Type A Aortic Dissection: A Transcriptome Pilot Analysis of Human Ascending Aortic Tissues.

Stanford type A aortic dissection (TAAD) is one of the most dangerous diseases of acute aortic syndrome. Molecular pathological studies on TAAD can aid in understanding the disease comprehensively and can provide insights into new diagnostic markers and potential therapeutic targets. In this study, we defined the molecular pathology of TAAD by performing transcriptome sequencing of human ascending aortic tissues. Pathway analysis revealed that activated inflammation, cell death and smooth muscle cell degeneration are the main pathological changes in aortic dissection. However, autophagy is considered to be one of the most important biological processes, regulating inflammatory reactions and degenerative changes. Therefore, we focused on the pathological role of autophagy in aortic dissection and identified 10 autophagy-regulated hub genes, which are all upregulated in TAAD. These results indicate that exaggerated autophagy participates in the pathological process of aortic dissection and may provide new insight for further basic research on TAAD.

Occupational Exposure to Endotoxin along a Municipal Scale Fecal Sludge Collection and Resource Recovery Process in Kigali, Rwanda.

Background: Little is known about occupational exposures that occur along fecal sludge collection and resource recovery processes. This study characterizes inhaled endotoxin exposure to workers of a municipal scale fecal sludge-to-fuel processes in Kigali, Rwanda. Methods: Forty-two task-based air samples were collected from workers in five tasks along the fecal sludge collection and resource recovery process. Samples were processed for endotoxin using the limulus amebocyte lysate (LAL) test. To account for exposure variability and compare measured concentrations to established exposure limits, we used Monte Carlo modeling methods to construct distributions representing full eight-hour (8-h) exposures to endotoxin across eight exposure scenarios. Results: Geometric mean (GM) endotoxin concentrations in task-based samples ranged from 11-3700 EU/m3 with exposure concentrations increasing as the dryness of the fecal sludge increased through processing. The thermal dryer task had the highest endotoxin concentrations (GM = 3700 EU/m3) and the inlet task had the lowest (GM = 11 EU/m3). The geometric means (GM) of modeled 8-h exposure concentrations were between 6.7-960 EU/m3 and highest for scenarios which included the thermal dryer task in the exposure scenario. Conclusions: Our data suggest the importance of including worker exposure considerations in the design of nascent fecal sludge management processes. The methods used in this study combine workplace sampling with stochastic modeling and are useful for exposure assessment in resource constrained contexts.