Exercise Cardiac Catheterization for Hemodynamic Evaluation of Paradoxical Low-Flow Low-Gradient Severe Aortic Stenosis

Patients with paradoxical low-flow low-gradient aortic stenosis pose a diagnostic challenge when it comes to assessing the severity of aortic stenosis (AS) noninvasively. We describe 2 patients who underwent exercise cardiac catheterization to augment their cardiac output and assess the severity of AS invasively to allow differentiation of true severe AS from pseudo-severe AS.

Predicting postoperative systolic dysfunction in mitral regurgitation: CT vs. echocardiography

Introduction

Volume overload from mitral regurgitation can result in left ventricular systolic dysfunction. To prevent this, it is essential to operate before irreversible dysfunction occurs, but the optimal timing of intervention remains unclear. Current echocardiographic guidelines are based on 2D linear measurement thresholds only. We compared volumetric CT-based and 2D echocardiographic indices of LV size and function as predictors of post-operative systolic dysfunction following mitral repair.

Methods

We retrospectively identified patients with primary mitral valve regurgitation who underwent repair between 2005 and 2021. Several indices of LV size and function measured on preoperative cardiac CT were compared with 2D echocardiography in predicting post-operative LV systolic dysfunction (LVEFecho <50%). Area under the curve (AUC) was the primary metric of predictive performance.

Results

A total of 243 patients were included (mean age 57 ± 12 years; 65 females). The most effective CT-based predictors of post-operative LV systolic dysfunction were ejection fraction [LVEFCT; AUC 0.84 (95% CI: 0.77-0.92)] and LV end systolic volume indexed to body surface area [LVESViCT; AUC 0.88 (0.82-0.95)]. The best echocardiographic predictors were LVEFecho [AUC 0.70 (0.58-0.82)] and LVESDecho [AUC 0.79 (0.70-0.89)]. LVEFCT was a significantly better predictor of post-operative LV systolic dysfunction than LVEFecho (p = 0.02) and LVESViCT was a significantly better predictor than LVESDecho (p = 0.03). Ejection fraction measured by CT demonstrated significantly greater reproducibility than echocardiography.

Discussion

CT-based volumetric measurements may be superior to established 2D echocardiographic parameters for predicting LV systolic dysfunction following mitral valve repair. Validation with prospective study is warranted.

Thoracic Aortic Aneurysmal Disease: Comprehensive Recommendations for the Primary Care Physician

Thoracic aortic aneurysm (TAA) is a commonly encountered disease that is defined as aortic dilation with an increase in diameter of at least 50% greater than the expected age- and sex-adjusted size. Thoracic aortic aneurysms are described by their size, location, morphology, and cause. Primary care clinicians and other noncardiologists are often the first point of contact for patients with TAA. This review is intended to provide them with basic information on the differential diagnosis, diagnostic evaluation, and medical and surgical management of TAAs. Management decisions depend on having as precise a diagnosis as possible. Fortunately, this can often be achieved with a stepwise diagnostic approach that incorporates imaging and targeted genetic testing. Our review includes recommendations. In this review, we discuss these issues at a basic level and include recommendations for patients considering pregnancy.

Transcatheter edge-to-edge repair for tricuspid valve regurgitation in apolipoprotein A-I-associated cardiac amyloidosis: case report

Background

Amyloidosis is defined by abnormal protein folding and subsequent deposition in tissues. Cardiac involvement is usually related to misfolded monoclonal immunoglobulin light chains or misfolded transthyretin; however, apolipoprotein A-1-associated amyloidosis is a hereditary form of amyloidosis resulting from mutations in the AAPOA1 gene that can also result in cardiac amyloidosis. Although there have been advancements in noninvasive algorithms for the diagnosis of cardiac amyloidosis, endomyocardial biopsy (EMB) may still be warranted. All individuals undergoing EMB are susceptible to complications, including tricuspid valve injury resulting in severe tricuspid valve regurgitation.

Case summary

Our patient is a 70-year-old white man presented with symptoms of dyspnoea on exertion and decreased functional capacity, diagnosed previously with apolipoprotein A-I cardiac amyloidosis, confirmed by EMB. He developed progressive right-sided heart failure secondary to iatrogenic flail tricuspid leaflet related to the diagnostic EMB. He underwent a successful transcatheter tricuspid valve edge-to-edge repair with 4D intracardiac echocardiographic guidance. At the recent follow-up, the patient showed improved symptoms, with increased stamina, and transoesophageal echocardiography revealed a 65% ejection fraction and mild tricuspid regurgitation (TR).

Discussion

Tricuspid valve injury is one of the complications associated with EMB, which can result in severe TR. Transcatheter tricuspid valve edge-to-edge repair can be a useful option for patients considered too high risk for surgical intervention, such as those with advanced cardiac amyloidosis.

Percutaneous Removal of Left Atrial Myxoma: The FLORIDA Procedure

Surgical resection has been the treatment of choice for cardiac myxomas, but older age and comorbidities relegate many patients to observation. Pure percutaneous removal of left atrial myxomas is both intriguing and challenging. We report a successful percutaneous technique for removal of left atrial cardiac myxoma in a nonsurgical candidate. (Level of Difficulty: Advanced.).

Universal DNA methylation age across mammalian tissues

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

The Evolving Etiologic and Epidemiologic Portrait of Pericardial Disease

Pericardial disease includes a variety of conditions, including inflammatory pericarditis, pericardial effusions, constrictive pericarditis, pericardial cysts, and primary and secondary pericardial neoplasms. The true incidence of this varied condition is not well established, and the causes vary greatly across the world. This review aims to describe the changing pattern of epidemiology of pericardial disease and to provide an overview of causative etiologies. Idiopathic pericarditis (assumed most often to be viral) remains the most common etiology for pericardial disease globally, with tuberculous pericarditis being most common in developing countries. Other important etiologies include fungal, autoimmune, autoinflammatory, neoplastic (both benign and malignant), immunotherapy-related, radiation therapy-induced, metabolic, postcardiac injury, postoperative, and postprocedural causes. Improved understanding of the immune pathophysiological pathways has led to identification and reclassification of some idiopathic pericarditis cases into autoinflammatory etiologies, including immunoglobulin G (IgG)4-related pericarditis, tumour necrosis factor receptor-associated periodic syndrome (TRAPS), and familial Mediterranean fever in the current era. Contemporary advances in percutaneous cardiac interventions and the recent COVID-19 pandemic have also resulted in changes in the epidemiology of pericardial diseases. Further research is needed to improve our understanding of the etiologies of pericarditis, using the assistance of contemporary advanced imaging techniques and laboratory testing. Careful consideration of the range of potential causes and local epidemiologic patterns of causality are important for the optimization of diagnostic and therapeutic approaches.

Utility of CT and MRI in Tricuspid Valve Interventions

Transcatheter tricuspid valve interventions (TTVIs) comprise a variety of catheter-based interventional techniques for treatment of tricuspid regurgitation (TR) in patients at high surgical risk and those with failed previous surgeries. Several TTVI devices with different mechanisms of action are either currently used or in preclinical evaluation. Echocardiography is the first-line modality for evaluation of tricuspid valve disease that provides information on tricuspid valve morphology, mechanism of TR, and hemodynamics. Cardiac CT and MRI have several advantages for a comprehensive preprocedure evaluation. CT and MRI provide complementary information to that of echocardiography on the mechanism and cause of TR. MRI can quantify the severity of TR using indirect or direct techniques that involve two-dimensional or four-dimensional flow sequences. MRI and CT can also accurately quantify right ventricular volumes and function, which is crucial for timing of intervention. CT provides comprehensive three-dimensional information on the morphology of the valve, annulus, subvalvular apparatus, and adjacent structures. CT is the procedure of choice for evaluation of several device-specific measurements, including tricuspid annulus dimensions, annulus-to-right coronary artery distance, leaflet morphology, coaptation gaps, caval dimensions, and cavoatrial-to-hepatic vein distance. CT allows evaluation of the vascular access as well as optimal procedure fluoroscopic angles and catheter trajectory. Postprocedure CT and MRI are useful in detection of complications such as paravalvular leak, pseudoaneurysm, thrombus, pannus, infective endocarditis, and device migration. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Prolonged Orbital Relaxation by Locally Modified Phonon Density of States for the SiV^{-} Center in Nanodiamonds

Coherent quantum systems are a key resource for emerging quantum technology. Solid-state spin systems are of particular importance for compact and scalable devices. However, interaction with the solid-state host degrades the coherence properties. The negatively charged silicon vacancy center in diamond is such an example. While spectral properties are outstanding, with optical coherence protected by the defects symmetry, the spin coherence is susceptible to rapid orbital relaxation limiting the spin dephasing time. A prolongation of the orbital relaxation time is therefore of utmost urgency and has been tackled by operating at very low temperatures or by introducing large strain. However, both methods have significant drawbacks: the former requires use of dilution refrigerators and the latter affects intrinsic symmetries. Here, a novel method is presented to prolong the orbital relaxation with a locally modified phonon density of states in the relevant frequency range, by restricting the diamond host to below 100 nm. Subsequently measured coherent population trapping shows an extended spin dephasing time compared to the phonon-limited time in a pure bulk diamond. The method works at liquid helium temperatures of few Kelvin and in the low-strain regime.

Congenital Heart Disease in Adults with Autosomal Dominant Polycystic Kidney Disease

INTRODUCTION

Autosomal dominant polycystic kidney disease (ADPKD) is caused mainly by pathogenic variants in PKD1 or PKD2 encoding the polycystin-1 and -2 proteins. Polycystins have shown to have an essential role in cardiac development and function in animal models. In the current study, we describe the clinical association between ADPKD and congenital heart disease (CHD).

METHODS

Medical records from Mayo Clinic were queried for all patients with confirmed ADPKD and CHD between 1993 and 2020. CHD was categorized into left-to-right shunt, obstructive, and complex lesions. Patent foramen ovale, mitral valve prolapse, and bicuspid aortic valve anomalies were excluded.

RESULTS

Twenty-five out of 1,359 (1.84%) ADPKD patients were identified to have CHD. Of these, 84% were Caucasians and 44% were males. The median (Q1-Q3) age (years) at CHD diagnosis was 12.0 (2.0-43.5). Fourteen patients (56%) had left-to-right shunt lesions, 6 (24%) had obstructive lesions and 5 (20%) complex lesions. Seventeen patients (68%) had their defects surgically corrected at a median age (Q1-Q3) of 5.5 (2.0-24.7). Among 13 patients with available genetic testing, 12 (92.3%) had PKD1 pathogenic variants, and none had PKD2. The median (Q1-Q3) age at last follow-up visit was 47.0 (32.0-62.0) and median (Q1-Q3) eGFR was 35.8 (11.4-79.0) mL/min/1.73 m2. Three patients (12%) died; all of them had left-to-right shunt lesions.

DISCUSSION/CONCLUSION

We observed a higher CHD frequency in ADPKD than the general population (1.84 vs. 0.4%). While only PKD1 pathogenic variants were identified in this cohort, further studies are needed to confirm this novel finding and understand the role of polycystins in the development of the heart and vessels.

A review on application of next-generation sequencing methods for profiling of protozoan parasites in water: Current methodologies, challenges, and perspectives

The advancement in metagenomic techniques has provided novel tools for profiling human parasites in environmental matrices, such as water and wastewater. However, application of metagenomic techniques for the profiling of protozoan parasites in environmental matrices is not commonly reported in the literature. The key factors leading to the less common use of metagenomics are the complexity and large eukaryotic genome, the prevalence of small parasite populations in environmental samples compared to bacteria, difficulties in extracting DNA from (oo)cysts, and limited reference databases for parasites. This calls for further research to develop optimized methods specifically looking at protozoan parasites in the environment. This study reviews the current workflow, methods and provide recommendations for the standardization of techniques. The article identifies and summarizes the key methods, advantages, and limitations associated with metagenomic analysis, like sample pre-processing, DNA extraction, sequencing approaches, and analysis methods. The study enhances the understanding and application of standardized protocols for profiling of protozoan parasite community from highly complexe samples and further creates a resourceful comparison among datasets without any biases.

P4138Clinical differences between methamphetamine and non-methamphetamine associated non-ischemic dilated cardiomyopathy

Background

Methamphetamine associated cardiomyopathy (MACM) is an increasingly recognized form of dilated cardiomyopathy around the globe which remains poorly characterized.

Purpose

To compare the clinical characteristics of MACM to those of non-MA associated dilated CM (NMACM).

Methods

Consecutive patients with MACM presenting to our institution between Jun 2018 and Jan 2019 were prospectively studied and compared to an age and gender-matched cohort of dilated non-ischemic CM cases.

Results

Seventy patients were studied (35 MACM and 35 NMACM). Mean age was similar between groups (49±9 vs. 48±10 years, p=0.465) and 97% of patients were male. Median duration of MA use prior to cardiomyopathy diagnosis was 5 years (range 0–30). Patients were predominantly Hispanic in both groups (48% vs. 62%, p=0.229), but with a greater proportion of Caucasians in the MACM group compared to NMACM (26% vs 6%, p=0.045).MACM was characterized by lower left ventricular ejection fraction (LVEF) and greater left ventricular end diastolic volume (LVEDV) compared to NMACM. RV dilation was present more often in MACM cases (Table). Years of MA use was associated with greater LA volumes (R2= 0.13, p=0.048). Association with larger LVEDV and incidence of RV dilation were borderline significant (R2= 0.11, p=0.054 and p=0.058 respectively). The amount of MA used per week correlated with higher RVSP (R2=0.317, p=0.004). Polysubstance abuse was associated with greater LVEF (p=0.028), lower LVEDV (p=0.037) and lower LV mass (p=0.004).

Echocardiographic parameters MACM Non-MACM p-value LVEDV (ml) 215 (62) 181 (40) 0.009* LVESV (ml) 166 (63) 133 (41) 0.017* LVEF (%) 20 (8) 26 (10) 0.006* LV Mass (g) 311 (109) 285 (81) 0.286 LA Volume (ml) 88 (26) 85 (29) 0.670 RV Dilation (no.) 23 (65.7%) 14 (40.0%) 0.027* Reduced RV Function (no.) 21 (60.0%) 21 (60.0%) 0.596 RVSP (mmHg) 40 (14) 44 (12) 0.671 RAP (mmHg) 9 (5) 10 (5) 0.682 Intracardiac Thrombus (no.) 3 (8.6%) 2 (5.7%) 0.500 Mean values are reported with standard deviation. *p<0.05.

Conclusion

MACM is associated with higher degree of LV and RV dilatation as well as LV systolic dysfunction when compared to matched NMACM cases. Years of MA use and amount of MA consumed appear to influence severity of disease.

Acknowledgement/Funding

None

P4415Long obstructive sleep apneas as a biomarker of atrial fibrillation

Background

Even though obstructive sleep apnea (OSA) is strongly associated with atrial fibrillation (AF), the use of traditional OSA scoring by apnea hypopnea index (AHI) did not result in improved arrhythmia outcomes in recent randomized trials. Longer OSA episodes lead to stronger pro-arrhythmic changes, and whether very long OSA episodes are more prevalent in AF patients remains unknown.

Purpose

We hypothesized that AF patients with mild-moderate OSA manifest greater percentage of long (>20s), very long (>30s), and extremely long (>40s) OSA episodes, compared to control OSA patients matched to AHI, age and sex.

Methods

From patients studied with diagnostic polysomnography in our laboratory between 2016 and 2018, we selected 22 patients with mild-moderate untreated OSA of which 11 patients had history of paroxysmal AF and 11 patients did not have any cardiac history. The length, oxygen desaturation, and relationship to neighboring events was manually re-measured in all recorded apnea and hypopnea events.

Results

In the 22 included patients (age 62.5±9.1 years, AHI 12.8±6.1, 40% female) we recorded 1021 apneas: 508 in the AF group and 513 in the control group. AF patients had longer apneas compared to the patients without AF history (mean length 28.7±11.7s vs. 23.3±9.9s; p<0.0001). The proportion of apneas that were long (>20s), very long (>30s), and extremely long (>40s) was greater in the AF group as compared to the control (p=0.0039, p=0.0215, p=0.0104, respectively; see figure). The acute oxygen saturation drops (>2%) during apneas were comparable between the AF group and control groups (p=0.13), but the long (>20s) apneas were prone to greater oxygen desaturations.

Length of Apneas

Conclusions

While traditional scoring of OSA focuses on episodes lasting >10s, our data newly show that longer durations of OSA events are particularly prevalent in AF patients. These results, combined with recent mechanistic studies showing that longer apneas exert greater pro-arrhythmic effect on atrial conduction, suggest that novel scoring of OSA placing more weight on longer apneas should be explored, especially when screening and titrating OSA therapy in patients at risk of AF.

Abstract P3-06-18: Comprehensive genomic profiling of carcinosarcomas of the breast

Background:

Carcinosarcomas of the breast (BCSC) are exceptionally rare and the underlying genomic drivers are still being elucidated. Comprehensive genomic profiling (CGP) determines the tumor mutation burden (TMB) and identifies all four classes of genomic alterations (GA) that have potential to direct personalized treatment strategies.

Methods:

CGP by hybridization capture of exons from up to 315 cancer-related genes and select introns of 28 genes commonly rearranged in cancer was applied to ≥ 50ng of DNA extracted from 9 consecutive BCSC and sequenced to high, uniform median coverage (&gt;500X). Tumor mutational burden (TMB) was determined on 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined by principal components analysis of optimized loci.

Results:

The 9 BCSC patients had a median age of 57 yrs (range 49-78 yrs). CGP was performed on the primary BCSC in 4 cases and on metastasis biopsies in 5 cases (4 lung and 1 lymph node). The mean GA/tumor was 6.6 and clinically relevant GA (CRGA)/tumor was 1.3. The most frequent non-CRGA were in TP53 (89%), MYC (56%) and LYN (40%). The most frequent CRGA were in PIK3CA (33%), and NF1, BRCA1, PTEN, RICTOR, FGFR1, AKT2 and STK11 (all at 11%). The median TMB for all BCSC was 2.4 mut/Mb with 1 (11%) tumor with a TMB &gt; 20 mut/Mb and 8 BCSC (88%) with TMB &lt; 5 mut/Mb. Five of 5 BCSC (100%) that were available for MSI status testing were microsatellite stable.

Conclusions:

On CGP, BCSC feature a high frequency of GA, but only a modest frequency of CRGA and high TMB. However, when the CRGA and TMB positive cases are combined (77.8% overall in this series), the opportunity for personalized targeted and immunotherapies are significant. Thus, further investigation of precision therapies for BCSC in the clinical trial setting appear warranted.

Citation Format: Gay LM, Elvin JA, Vergilio J-A, Killian JK, Ramkissoon S, Severson E, Daniel S, Hammerich A, Sokol E, Frampton G, Chung J, Trabucco S, Ali S, Reddy P, Schrock AB, Miller VA, Ross JS. Comprehensive genomic profiling of carcinosarcomas of the breast [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-06-18.

Preliminary report: Surgical outcomes following genitoplasty in children with moderate to severe genital atypia

INTRODUCTION

Prior studies of outcomes following genitoplasty have reported high rates of surgical complications among children with atypical genitalia. Few studies have prospectively assessed outcomes after contemporary surgical approaches.

OBJECTIVE

The current study reported the occurrence of early postoperative complications and of cosmetic outcomes (as rated by surgeons and parents) at 12 months following contemporary genitoplasty procedures in children born with atypical genitalia.

STUDY DESIGN

This 11-site, prospective study included children aged ≤2 years, with Prader 3-5 or Quigley 3-6 external genitalia, with no prior genitoplasty and non-urogenital malformations at the time of enrollment. Genital appearance was rated on a 4-point Likert scale. Paired t-tests evaluated differences in cosmesis ratings.

RESULTS

Out of 27 children, 10 were 46,XY patients with the following diagnoses: gonadal dysgenesis, PAIS or testosterone biosynthetic defect, severe hypospadias and microphallus, who were reared male. Sixteen 46,XX congenital adrenal hyperplasia patients were reared female and one child with sex chromosome mosaicism was reared male. Eleven children had masculinizing genitoplasty for penoscrotal or perineal hypospadias (one-stage, three; two-stage, eight). Among one-stage surgeries, one child had meatal stenosis (minor) and one developed both urinary retention (minor) and urethrocutaneous fistula (major) (Summary Figure). Among two-stage surgeries, three children developed a major complication: penoscrotal fistula, glans dehiscence or urethral dehiscence. Among 16 children who had feminizing genitoplasty, vaginoplasty was performed in all, clitoroplasty in nine, external genitoplasty in 13, urethroplasty in four, perineoplasty in five, and total urogenital sinus mobilization in two. Two children had minor complications: one had a UTI, and one had both a mucosal skin tag and vaginal mucosal polyp. Two additional children developed a major complication: vaginal stenosis. Cosmesis scores revealed sustained improvements from 6 months post-genitoplasty, as previously reported, with all scores reported as good or satisfied.

DISCUSSION

In these preliminary data from a multi-site, observational study, parents and surgeons were equally satisfied with the cosmetic outcomes 12 months after genitoplasty. A small number of patients had major complications in both feminizing and masculinizing surgeries; two-stage hypospadias repair had the most major complications. Long-term follow-up of patients at post-puberty will provide a better assessment of outcomes in this population.

CONCLUSION

In this cohort of children with moderate to severe atypical genitalia, preliminary data on both surgical and cosmetic outcomes were presented. Findings from this study, and from following these children in long-term studies, will help guide practitioners in their discussions with families about surgical management.

Obstetric outcomes and antenatal access among adolescent pregnancies in Kwazulu-Natal, South Africa

Background: Pregnancy among adolescents in South Africa is a growing concern as it may be associated with adverse socioeconomic and health impacts. Timeous initiation and optimal utilisation of antenatal care (ANC) services is imperative to ensure positive pregnancy outcomes. However, this is not always possible owing to various challenges. Methods: A multi-method study design using both retrospective record review and qualitative interviews was undertaken at a district hospital on the North Coast of KwaZulu-Natal, South Africa. Data on ANC attendance trends and obstetric/perinatal outcomes for all recorded adolescent pregnancies (13–16 years) at the district hospital under study was collected over 3 years (2011–2013) (n = 314). Qualitative interviews with randomly selected pregnant adolescents were conducted to assess experiences of ANC access and utilisation. Results: Late ANC booking and reduced ANC visits were common for adolescent pregnancies. Under-utilisation of ANC (i.e. less than 4 visits) was significantly associated with lower gestational age (< 37 weeks) (OR = 2.64; 95% CI = 1.04; 6.74; p < 0.05). Low birthweight, low Apgar scores as well as the incidence of maternal anaemia and pregnancy-induced hypertension (PIH) were found to be related to late ANC booking. In-depth interviews suggested that teenagers suffered emotional vulnerability linked to family, partner and financial support. They discussed various barriers linked with accessing ANC while acknowledging perceived benefits. Conclusion: Adolescent pregnancy was associated with late booking and reduced ANC visits, which was a risk for adverse maternal health outcomes. In-depth interviews suggested numerous challenges associated with ANC access including; financial barriers, attitude of healthcare workers (HCWs), long queues, distance travelled to access ANC services, human immunodeficiency virus (HIV) status and a lack of knowledge. (Full text of the research articles are available online at www.medpharm.tandfonline.com/ojfp) S Afr Fam Pract 2017; DOI: 10.1080/20786190.2017.133378

Microbial metabolites and graft versus host disease

The health of mammals is a reflection of the diversity and composition of the intestinal microbiota. Alterations in the composition and functions of the intestinal microbiota have been implicated in multiple disease processes. The impact of the microbiota in health and disease is in part a function of the nutrient processing and release of metabolites. Recent studies have uncovered a major role for microbial metabolites in the function of the host immune system by which they influence disease processes such as acute graft versus host disease (GVHD), which is the main complication of allogeneic hematopoietic cell transplantation (allo-HCT). The mechanisms of acute GVHD regulation by the complex microbial community and the metabolites released by them are unclear. In this review we summarize major findings of how microbial metabolites interact with the immune system and discuss how these interactions could impact acute GVHD.

The association between biopsychosocial factors and disability in a national health survey in South Africa

The association between psychosocial factors and disability is less clear. This study investigated the biological and psychosocial (employment and psychological distress) factors associated with level of disability in an adult sample in South Africa. Data were analysed from a cross-sectional survey among adults aged 18-64 (n = 4974). Multiple linear regression was used to investigate the associations of the selected variables with disability. The mean percentage score on the WHODAS scale of disability was 5.31% (95% CI: 4.74-5.88). Age (p < 0.001) and race (p = 0.0002) were significantly associated with disability, and history of stroke (β = 7.19, 95% CI: 3.19-11.20) and heart-related conditions (β = 2.08, 95% CI: [0.23-3.93) showed positive associations. Of the psychosocial variables, psychological distress (β = 10.49 [8.63-12.35]) showed a strong positive association while employment (-1.62 [-2.36 to -0.88]) showed a negative association with disability. The association between demographic factors, medical conditions and increased disability confirms the findings in the literature. The finding that psychological distress is associated with increased disability has not been frequently reported. This study highlights specific psychosocial targets that may be usefully addressed by health policies and interventions in order to improve disability management.

Using observations and source specific model tracers to characterize pollutant transport during FRAPPÉ and DISCOVER-AQ

Transport is a key parameter in air quality research and plays a dominant role in the Colorado Northern Front Range Metropolitan Area (NFRMA), where terrain induced flows and recirculation patterns can lead to vigorous mixing of different emission sources. To assess different transport processes and their connection to air quality in the NFRMA during the FRAPPÉ and DISCOVER-AQ campaigns in summer 2014, we use the Weather Research and Forecasting Model with inert tracers. Overall, the model represents well the measured winds and the inert tracers are in good agreement with observations of comparable trace gas concentrations. The model tracers support the analysis of surface wind and ozone measurements and allow for the analysis of transport patterns and interactions of emissions. A main focus of this study is on characterizing pollution transport from the NFRMA to the mountains by mountain-valley flows and the potential for recirculating pollution back into the NFRMA. One such event on 12 August 2014 was well captured by the aircraft and is studied in more detail. The model represents the flow conditions and demonstrates that during upslope events, frequently there is a separation of air masses that are heavily influenced by oil and gas emissions to the North and dominated by urban emissions to the South. This case study provides evidence that NFRMA pollution not only can impact the nearby Foothills and mountain areas to the East of the Continental Divide, but that pollution can "spill over" into the valleys to the West of the Continental Divide.

Palladium-Catalyzed Cross-Coupling of 1,3,4-Oxadiazoles and Styrenes: An Efficient Method to Synthesize 2-Alkenyl-1,3,4- Oxadiazoles§

2-Alkenyl-1,3,4-oxadiazole derivatives have been prepared by cross-coupling of 1,3,4-oxadiazoles with styrenes by using palladium(II) trifluoroacetate [Pd(TFA)2] as a catalyst, 1,10-phenanthroline as a ligand, silver trifluoroacetate as an oxidant, and toluene as a solvent. The products were formed in high yields and no byproducts were detected.