Novel high throughput screen reports that benzo(a)pyrene overrides mouse trophoblast stem cell multipotency, inducing SAPK activity, HAND1 and differentiated trophoblast giant cells

INTRODUCTION

Cultured mouse trophoblast stem cells (mTSC) maintain proliferation/normal stemness (NS) under FGF4, which when removed, causes normal differentiation (ND). Hypoxic, or hyperosmotic stress forces trophoblast giant cells (TGC) differentiate. Hypoxic, hyperosmotic, and genotoxic benzo(a)pyrene (BaP), which is found in tobacco smoke, force down-regulation of inhibitor of differentiation (Id)2, enabling TGC differentiation. Hypoxic and hyperosmotic stress induce TGC by SAPK-dependent HAND1 increase. Here we test whether BaP forces mTSC-to-TGC while inducing SAPK and HAND1.

METHODS

Hand1 and SAPK activity were assayed by immunoblot, mTSC-to-TGC growth and differentiation were assayed at Tfinal after 72hr exposure of BaP, NS, ND, Retinoic acid (RA), or sorbitol. Nuclear-stained cells were micrographed automatically by a live imager, and assayed by ImageJ/FIJI, Biotek Gen 5, AIVIA proprietary artificial intelligence (AI) software or open source, CellPose artificial intelligence/AI software.

RESULTS

BaP (0.05-1μM) activated SAPK and HAND1 without diminishing growth. TSC-to-TGC differentiation was assayed with increasingly accuracy for 2-4 N cycling nuclei and >4 N differentiating TGC nuclei, using ImageJ/FIJI, Gen 5, AIVIA, or CellPose AI software. The AIVIA and Cellpose AI software matches human accuracy. The lowest BaP effects on SAPK activation/HAND1 increase are >10-fold more sensitive than similar effects for mESC. RA induces 44-47% 1st lineage TGC differentiation, but the same RA dose induces only 1% 1st lineage mESC differentiation.

DISCUSSION

First, these pilot data suggest that mTSC can be used in high throughput screens (HTS) to predict toxicant exposures that force TGC differentiation. Second, mTSC differentiated more cells than mESC for similar stress exposures, Third, open source AI can replace human micrograph quantitation and enable a miscarriage-predicting HTS.

Prevalence and Characteristics of Patients with Median Arcuate Ligament Syndrome in a Cohort Diagnosed with Celiac Artery Compression

BACKGROUND

Median arcuate ligament syndrome (MALS) is a frequent differential diagnosis in patients with postprandial abdominal symptoms, but diagnosis remains challenging. The aim of this study was to identify characteristics of patients who had MALS compared with non-MALS patients among a cohort of patients diagnosed with celiac artery compression (CAC).

STUDY DESIGN

An IRB-approved retrospective chart review (2000 to 2021) of patients at our institution with a discharge diagnosis of CAC was performed. Medical record review for clinical symptoms and findings consistent with MALS was performed.

RESULTS

Two hundred ninety-three patients with a diagnosis of CAC were identified; 59.7% were women, and average age was 63.9 ± 20.2 years. Sixty-nine (23.5%) patients with CAC had MALS. There were no significant differences in sex or race between MALS and non-MALS patients, but MALS patients were younger (55.7 vs 68.1, p < 0.001). There was no significant difference in gastrointestinal comorbidities between the 2 groups. Patients with MALS were less likely to have diabetes (12.5% vs 26.9%), renal disease (4.6% vs 8.2%), hypertension (41.5% vs 70.3%), mesenteric atherosclerotic disease (14% vs 61.9%), and peripheral artery disease (15.0% vs 39.7%).

CONCLUSIONS

We demonstrate a novel observation that MALS patients tend to have fewer atherosclerotic characteristics than non-MALS patients with CAC. Patients in our study with MALS were more likely to be younger, women, and presenting with epigastric pain. MALS patients had a significantly lower incidence of diabetes, hypertension, renal disease, mesenteric artery disease, and peripheral arterial disease compared with the non-MALS group. An important clinically relevant feature of MALS patients may be their lack of atherosclerotic phenotype compared with non- MALS patients with CAC.

American Indians travel great distances for obstetrical care: Examining rural and racial disparities

Rural, American Indian/Alaska Native (AI/AN) people, a population at elevated risk for complex pregnancies, have limited access to risk-appropriate obstetric care. Obstetrical bypassing, seeking care at a non-local obstetric unit, is an important feature of perinatal regionalization that can alleviate some challenges faced by this rural population, at the cost of increased travel to give birth. Data from five years (2014-2018) of birth certificates from Montana, along with the 2018 annual survey of the American Hospital Association (AHA) were used in logistic regression models to identify predictors of bypassing, with ordinary least squares regression models used to predict factors associated with the distance (in miles) birthing people drove beyond their local obstetric unit to give birth. Logit analyses focused on hospital-based births to Montana residents delivered during this time period (n = 54,146 births). Distance analyses focused on births to individuals who bypassed their local obstetric unit to deliver (n = 5,991 births). Individual-level predictors included maternal sociodemographic characteristics, location, perinatal health characteristics, and health care utilization. Facility-related measures included level of obstetric care of the closest and delivery hospitals, and distance to the closest hospital-based obstetric unit. Findings suggest that birthing people living in rural areas and on American Indian reservations were more likely to bypass to give birth, with bypassing likelihood depending on health risk, insurance, and rurality. AI/AN and reservation-dwelling birthing people traveled significantly farther when bypassing. Findings highlight that distance traveled was even farther for AI/AN people facing pregnancy health risks (23.8 miles farther than White people with pregnancy risks) or when delivering at facilities offering complex care (14-44 miles farther than White people). While bypassing may connect rural birthing people to more risk-appropriate care, rural and racial inequities in access persist, with rural, reservation-dwelling AI/AN birthing people experiencing greater likelihood of bypassing and traveling greater distances when bypassing.

Utility of Hook Sign in the Diagnosis of Median Arcuate Ligament Syndrome

OBJECTIVE

Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament (MAL) that often manifests with non-specific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral CTA, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristicss of the celiac artery to clinically relevant MALS.

DESIGN

Single-center retrospective study METHODS: An IRB-approved retrospective chart review from 2000-2021 of 293 patients at a tertiary academic center diagnosed with celiac artery compression (CAC) was performed. Patient demographics and symptoms of 69 patients who were diagnosed with symptomatic MALS were compared to 224 patients without MALS (but with CAC) per electronic medical record review. CTA images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual fold angle < 135 degrees) was recorded as well as stenosis (defined as >50% of luminal narrowing on imaging). Wilcoxon rank sum test and Chi-squared were utilized for comparative analysis. Logistic model was run to relate the presence of MALS with comorbidities and radiographic findings.

RESULTS

Imaging was available in 59 patients (25 males, 34 females) and 157 patients (60 males, 97 females) with and without MALS respectively. Patients with MALS were more likely to have a more severe FA (120.7 ± 33.6 vs. 134.8 ± 27.9, P = 0.002). Males with MALS were also more likely to have a more severe FA compared with males without MALS (111.1 ± 33.7 vs. 130.4 ± 30.4, P = 0.015). In patients with BMI > 25, MALS patients also had narrower FA compared with patients without MALS (112.6 ± 30.5 vs. 131.7 ± 30.3, P = 0.001). The FA was negatively correlated with BMI in patients with CAC . The hook sign and stenosis were associated with diagnosis of MALS (59.3% vs. 28.7%, P < 0.001, and 75.7% vs. 45.2%, P < 0.001, respectively). In logistic regression, pain, stenosis and a narrow FA were statistically significant predictors of the presence of MALS.

CONCLUSIONS

The upward deflection of the celiac artery in patients with MALS is more severe compared with patients without MALS. Consistent with prior literature, this bending of the celiac artery is negatively correlated with BMI in patients with and without MALS. When demographic variables and comorbidities are considered, a narrow FA is a statistically significant predictor of MALS. Regardless of MALS diagnosis, a hook sign was associated with narrower FA. While demographics and imaging findings may inform MALS diagnosis, clinicians should not rely on a visual assessment of a hook sign but should quantitatively measure the anatomic bending angle of the celiac artery to assist with the diagnosis and understand the outcomes.

A Dynamic In vitro developing testis model reflects structures and functions of testicular development in vivo

To better define appropriate applications of our 3-dimensional testicular co-culture as a model for reproductive toxicology, we evaluated the ability of the model to capture structural and functional elements that can be targeted by reproductive toxicants. Testicular co-cultures were prepared from postnatal day 5 male rats and cultured with a Matrigel overlay. Following a 2-day acclimation period, we characterized functional pathway dynamics by evaluating morphology, protein expression, testosterone concentrations, and global gene expression at a range of timepoints from experimental days 0 to 21. Western blotting confirmed expression of Sertoli cell, Leydig cell, and spermatogonial cell-specific protein markers. Testosterone detected in cell culture media indicates active testosterone production. Quantitative pathway analysis identified Gene Ontology biological processes enriched among genes significantly changing over the course of 21 days. Processes enriched among genes significantly increasing through time include general developmental processes (morphogenesis, tissue remodeling, etc.), steroid regulation, Sertoli cell development, immune response, and stress and apoptosis. Processes enriched among genes significantly decreasing over time include several related to male reproductive development (seminiferous tubule development, male gonad development, Leydig cell differentiation, Sertoli cell differentiation), all of which appear to peak in expression between days 1 and 5 before decreasing at later timepoints. This analysis provides a temporal roadmap for specific biological process of interest for reproductive toxicology in the model and anchors the model to sensitive phases of in vivo development, helping to define the relevance of the model for in vivo processes.

Ten second triage: A novel and pragmatic approach to major incident triage

Triage is a key principle in the effective management of major incidents and has traditionally been performed using an assessment of a casualty's physiology. However, it has become apparent from recent experiences of major incidents that physiological triage may practically not be possible, especially in the early stages of an incident. A key factor is the speed with which it is possible to perform triage, and subsequently, the speed at which key life-saving interventions (e.g., management of external haemorrhage and airway opening manoeuvres) are able to be performed simultaneously as part of the triage process. Addressing this issue was a priority for the review of major incident triage undertaken by NHS England and culminated in the development of the Ten Second Triage (TST) tool.

Factors associated with successful median arcuate ligament release in an international, multi-institutional cohort

OBJECTIVE

Prior research on median arcuate ligament syndrome has been limited to institutional case series, making the optimal approach to median arcuate ligament release (MALR) and resulting outcomes unclear. In the present study, we compared the outcomes of different approaches to MALR and determined the predictors of long-term treatment failure.

METHODS

The Vascular Low Frequency Disease Consortium is an international, multi-institutional research consortium. Data on open, laparoscopic, and robotic MALR performed from 2000 to 2020 were gathered. The primary outcome was treatment failure, defined as no improvement in median arcuate ligament syndrome symptoms after MALR or symptom recurrence between MALR and the last clinical follow-up.

RESULTS

For 516 patients treated at 24 institutions, open, laparoscopic, and robotic MALR had been performed in 227 (44.0%), 235 (45.5%), and 54 (10.5%) patients, respectively. Perioperative complications (ileus, cardiac, and wound complications; readmissions; unplanned procedures) occurred in 19.2% (open, 30.0%; laparoscopic, 8.9%; robotic, 18.5%; P < .001). The median follow-up was 1.59 years (interquartile range, 0.38-4.35 years). For the 488 patients with follow-up data available, 287 (58.8%) had had full relief, 119 (24.4%) had had partial relief, and 82 (16.8%) had derived no benefit from MALR. The 1- and 3-year freedom from treatment failure for the overall cohort was 63.8% (95% confidence interval [CI], 59.0%-68.3%) and 51.9% (95% CI, 46.1%-57.3%), respectively. The factors associated with an increased hazard of treatment failure on multivariable analysis included robotic MALR (hazard ratio [HR], 1.73; 95% CI, 1.16-2.59; P = .007), a history of gastroparesis (HR, 1.83; 95% CI, 1.09-3.09; P = .023), abdominal cancer (HR, 10.3; 95% CI, 3.06-34.6; P < .001), dysphagia and/or odynophagia (HR, 2.44; 95% CI, 1.27-4.69; P = .008), no relief from a celiac plexus block (HR, 2.18; 95% CI, 1.00-4.72; P = .049), and an increasing number of preoperative pain locations (HR, 1.12 per location; 95% CI, 1.00-1.25; P = .042). The factors associated with a lower hazard included increasing age (HR, 0.99 per increasing year; 95% CI, 0.98-1.0; P = .012) and an increasing number of preoperative diagnostic gastrointestinal studies (HR, 0.84 per study; 95% CI, 0.74-0.96; P = .012) Open and laparoscopic MALR resulted in similar long-term freedom from treatment failure. No radiographic parameters were associated with differences in treatment failure.

CONCLUSIONS

No difference was found in long-term failure after open vs laparoscopic MALR; however, open release was associated with higher perioperative morbidity. These results support the use of a preoperative celiac plexus block to aid in patient selection. Operative candidates for MALR should be counseled regarding the factors associated with treatment failure and the relatively high overall rate of treatment failure.

The functional lumbar index: Validation of a novel clinical assessment tool for individuals with low back pain

STUDY DESIGN

Retrospective Diagnostic Cohort Study.

LEVEL OF EVIDENCE

Level 3b.

OBJECTIVES

To examine the concurrent and predictive validity of a novel clinical assessment tool, the Functional Lumbar Index (FLI).

BACKGROUND

Lumbar surgeries have increased exponentially in the past decade, adding to healthcare costs without improving outcomes. Limitations in clinicians' abilities to identify those individuals who are most likely to benefit from surgery may be enhanced with an effective physical assessment tool.

METHODS

The FLI was assessed on 291 individuals (179 conservative and 113 pre-surgical) seeking care for low-back pain (LBP) over a 2.5-year period. The FLI consists of several physical performance tests (PPT) with a novel criterion-based scoring system. Pearson correlations and Poisson regression analysis were used to establish concurrent and predictive validity at alpha = 0.05.

RESULTS

The subscale FLI components showed good to excellent inter-rater reliability with intraclass correlation coefficient values as follows: front plank = .993, right side plank = .824, left side plank .861, Sorensen = 0.836, overhead squat = 0.937. A statistically significant, moderate negative correlation was observed between FLI and modified Oswestry Disability Index (r = -0.540, p < .001). Regression analysis showed the FLI as the only significant predictor (p = .004) of failed conservative management for individuals with LBP. An ROC curve showed significant group prediction of the FLI with an AUC of 0.788 (p < .001) and cut-off score of 7.5.

CONCLUSION

The FLI is a reliable and valid measure for predicting failed conservative care management in patients with LBP. Clinicians are encouraged to use the FLI as part of their physical assessment when screening individuals with LBP who might need surgical intervention. Further research is needed to determine validity of the FLI in other patient populations.

PUBLIC TRIAL REGISTRY

N/A.

Using Live Imaging and Fluorescence Ubiquitinated Cell Cycle Indicator Embryonic Stem Cells to Distinguish G1 Cell Cycle Delays for General Stressors like Perfluoro-Octanoic Acid and Hyperosmotic Sorbitol or G2 Cell Cycle Delay for Mutagenic Stressors like Benzo(a)pyrene

Lowest observable adverse effects level (LOAEL) is a standard point-of-departure dose in toxicology. However, first observable adverse effects level (FOAEL) was recently reported and is used, in this study, as one criterion to detect a mutagenic stimulus in a live imager. Fluorescence ubiquitinated cell cycle indicator (FUCCI) embryonic stem cells (ESC) are green in the S-G2-M phase of the cell cycle and not green in G1-phase. Standard media change here is a mild stress that delays G1-phase and media change increases green 2.5- to 5-fold. Since stress is mild, media change rapidly increases green cell number, but higher stresses of environmental toxicants and positive control hyperosmotic stress suppress increased green after media change. Perfluoro-octanoic acid (PFOA) and diethyl phthalate (DEP) previously suppressed progression of nongreen to green cell cycle progression. Here, bisphenol A (BPA), cortisol, and positive control hyperosmotic sorbitol also suppress green fluorescence, but benzo(a)pyrene (BaP) at high doses (10 μM) increases green fluorescence throughout the 74-h exposure. Since any stress can affect many cell cycle phases, messenger RNA (mRNA) markers are best interpreted in ratios as dose-dependent mutagens increase in G2/G1 and nonmutagens increase G1/G2. After 74-h exposure, RNAseq detects G1 and G2 markers and increasing BaP doses increase G2/G1 ratios but increasing hyperosmotic sorbitol and PFOA doses increase G1/G2 marker ratios. BaP causes rapid green increase in FOAEL at 2 h of stimulus, whereas retinoic acid caused significant green fluorescence increases only late in culture. Using a live imager to establish FOAEL and G2 delay with FUCCI ESC is a new method to allow commercial and basic developmental biologists to detect drugs and environmental stimuli that are mutagenic. Furthermore, it can be used to test compounds that prevent mutations. In longitudinal studies, uniquely provided by this viable reporter and live imager protocol, follow-up can be done to test whether the preventative compound itself causes harm.

Elucidating the role of the AFX2 endograft in endovascular treatment of aortic pathology

OBJECTIVE

The purpose of this study is to elucidate the role of the AFX2 platform in the endovascular treatment of aortic pathology.

METHODS

All procedures by a single surgeon resulting in implantation of a bifurcated unibody stent graft were retrospectively reviewed. Indications for selection of the AFX2 endograft in each case were evaluated. Aortic anatomy was determined via review of pre-operative computed tomography (CT) scans. Cumulative event probabilities for endoleak, reintervention, and mortality were estimated. Patient and procedural details were described using mean, standard deviation, medians, and interquartile range (IQR). Kaplan-Meier survival analysis estimated freedom from mortality and reintervention. Cumulative incidence probabilities were calculated as one minus the Kaplan-Meier estimator.

RESULTS

Between March 2018 and December 2020, the author (NN) used 142 aortic endografts in 142 patients. Of these, 46 (32.4%) were AFX2 endografts and the remaining were modular bifurcated devices, predominantly Medtronic Endurant II and Terumo Treo. No AFX-Strata or AFX-Duraply devices were placed. Amongst the patients who received an AFX2, mean age was 71.3 +/- 9.8 years with 84.8% male. Median operative time was 116 (86-166) minutes, with contrast dose of 79 (41-120) milliliters and fluoroscopy time of 12 (8.6-18) minutes. Overall, 78.3% (n=36) of AFX2 devices were placed in aortas with maximum true lumen diameter <5.0cm. Median postoperative follow-up was 1.7 years (IQR 1.0-2.4 years), with a maximum follow-up of 3.6 years. There was 1 patient lost to follow-up at 5 months. The 2-year incidence of type II endoleak, reintervention, and all-cause mortality was 12.7% (95% CI, 0-29.6%), 2.2% (95% CI, 0-6.3%), and 11.3% (95% CI, 0.1-2.1.2%), respectively. There were no type I or III endoleaks.

CONCLUSION

The AFX2 endograft plays a safe and effective role in treatment of infrarenal aortic pathologies that may be otherwise more technically challenging for traditional modular, bifurcated devices.

Evaluating disparities in access to obstetric services for American Indian women across Montana

PURPOSE

Pregnant women across the rural United States have increasingly limited access to obstetric care, especially specialty care for high-risk women and infants. Limited research focuses on access for rural American Indian/Alaskan Native (AIAN) women, a population warranting attention given persistent inequalities in birth outcomes.

METHODS

Using Montana birth certificate data (2014-2018), we examined variation in travel time to give birth and access to different levels of obstetric care (i.e., the proportion of individuals living within 1- and 2-h drives to facilities), by rurality (Rural-Urban Continuum Code) and race (White and AIAN people).

FINDINGS

Results point to limited obstetric care access in remote rural areas in Montana, especially higher-level specialty care, compared to urban or urban-adjacent rural areas. AIAN women traveled significantly farther than White women to access care (24.2 min farther on average), even compared to White women from similarly rural areas (5-13 min farther, after controlling for sociodemographic characteristics, risk factors, and health care utilization). AIAN women were 20 times more likely to give birth at a hospital without obstetric services and had less access to complex obstetric care. Poor access was particularly pronounced among reservation-dwelling AIAN women.

CONCLUSIONS

It is imperative to consider racial disparities and health inequities underlying poor access to obstetric services across rural America. Current federal policies aim to reduce maternity care professional shortages. Our findings suggest that racial disparities in access to complex obstetric care will persist in Montana unless facility-level infrastructure is also expanded to reach areas serving AIAN women.

Using a 3D handheld scanner to capture trochlear groove shape: proof of concept study

INTRODUCTION

Trochleoplasty is a surgical procedure used to treat patellar instability by modifying the trochlear groove. Analysis of the groove with a handheld scanner would enable accurate real-time planning and facilitate tailormade correction. We aimed to measure trochlear depth, sulcus angle, trochlear facet ratio, trochlear angle and lateral trochlear inclination angle and to establish inter- and intra-rater reliability for knee models to determine reliability and repeatability.

METHODS

The trochlear grooves of three knee models were scanned by two investigators. Three-dimensional reference models were created and surface-matched. Custom software was used to determine the desired parameters. The intraclass correlation coefficient (ICC) was used to determine test-retest reliability and the parameter results for each model that showed best reproducibility.

RESULTS

There was good interobserver reliability (trochlear depth, 1.0mm; sulcus angle, 2.7°; trochlear angle, 4.0°; lateral trochlear inclination angle, 4.0°), except in the trochlear facet ratio (32.0%) of one knee model. With outliers removed, the ICC was moderate to excellent in 73.34% of measurements, with trochlear depth showing the best reproducibility.

DISCUSSION

This feasibility study showed a handheld scanner in conjunction with supporting software can measure trochlear parameters with good to excellent inter- and intra-observer reliability.

199 Use of A 3D Hand-Held Scanner to Capture Trochlear Groove Shape, A Proof-of-Concept Study

Introduction

Trochleoplasty is a surgical procedure used to treat patellar instability through modifying the trochlear groove. Analysis of the groove with a hand-held scanner would enable accurate real time planning and facilitate tailor made correction. We aimed to measure trochlear depth, sulcus angle, trochlear facet ratio, trochlear angle and lateral trochlear inclination angle and establish inter- and intra-rater reliability for each knee model.

Method

The trochlear groove of the knee models was scanned by two investigators and 3D reference models created. These were surface matched and custom software along with Excel was utilised to determine the desired parameters. Intraclass correlation coefficient (ICC) was used for test-retest reliability and to determine which parameter results, for each model, showed the best reproducibility.

Results

There was good inter-observer reliability - trochlear depth (1.0 mm), sulcus angle (2.7°), trochlear angle (4.0°) and lateral trochlear inclination angle (4.0°), except in the trochlear facet ratio (32.0%) of one knee model. With outliers removed ICC was good-excellent in (46.7%) of measurements, with trochlear depth showing the best reproducibility.

Conclusions

This feasibility study showed that the hand-held scanner in conjunction with supporting software can measure trochlear parameters in a controlled environment and justifies extending research into its use in trochleoplasty.

Impact of solitary pulmonary nodule size on qualitative and quantitative assessment using 18F-fluorodeoxyglucose PET/CT: the SPUTNIK trial

PURPOSE

To compare qualitative and semi-quantitative PET/CT criteria, and the impact of nodule size on the diagnosis of solitary pulmonary nodules in a prospective multicentre trial.

METHODS

Patients with an SPN on CT ≥ 8 and ≤ 30 mm were recruited to the SPUTNIK trial at 16 sites accredited by the UK PET Core Lab. Qualitative assessment used a five-point ordinal PET-grade compared to the mediastinal blood pool, and a combined PET/CT grade using the CT features. Semi-quantitative measures included SUVmax of the nodule, and as an uptake ratio to the mediastinal blood pool (SURBLOOD) or liver (SURLIVER). The endpoints were diagnosis of lung cancer via biopsy/histology or completion of 2-year follow-up. Impact of nodule size was analysed by comparison between nodule size tertiles.

RESULTS

Three hundred fifty-five participants completed PET/CT and 2-year follow-up, with 59% (209/355) malignant nodules. The AUCs of the three techniques were SUVmax 0.87 (95% CI 0.83;0.91); SURBLOOD 0.87 (95% CI 0.83; 0.91, p = 0.30 versus SUVmax); and SURLIVER 0.87 (95% CI 0.83; 0.91, p = 0.09 vs. SUVmax). The AUCs for all techniques remained stable across size tertiles (p > 0.1 for difference), although the optimal diagnostic threshold varied by size. For nodules < 12 mm, an SUVmax of 1.75 or visual uptake equal to the mediastinum yielded the highest accuracy. For nodules > 16 mm, an SUVmax ≥ 3.6 or visual PET uptake greater than the mediastinum was the most accurate.

CONCLUSION

In this multicentre trial, SUVmax was the most accurate technique for the diagnosis of solitary pulmonary nodules. Diagnostic thresholds should be altered according to nodule size.

TRIAL REGISTRATION

ISRCTN - ISRCTN30784948. ClinicalTrials.gov - NCT02013063.

Subgingival microbiota of dogs with healthy gingiva or early periodontal disease from different geographical locations

BACKGROUND

Periodontal disease is the most common oral disease of dogs worldwide and results from a complex interplay between plaque bacteria, the host and environmental factors. Recent studies have enhanced our understanding of the associations between the plaque microbiota and canine periodontal disease. These studies, however, were limited in their geographical reach. Thus associations between the canine oral microbiota and geographical location were investigated by determining the composition of subgingival plaque samples from 587 dogs residing in the United Kingdom (UK), United States of America (USA), China and Thailand using 454-pyrosequencing.

RESULTS

After quality filtering 6,944,757 sequence reads were obtained and clustering of these at ≥98% sequence resulted in 280 operational taxonomic units (OTUs) following exclusion of rare OTUs (present at < 0.05% in all four countries). The subgingival plaque from dog populations located in the UK, USA, China and Thailand had a similar composition although the abundance of certain taxa varied significantly among geographical locations. Exploration of the effect of clinical status and age revealed a marked similarity among the bacteria associated with increased age and those associated with gingivitis: Young dogs and those with no gingivitis were dominated by taxa from the phyla Bacteroidetes and Proteobacteria whereas older dogs and those with moderate gingivitis were dominated by members of the Firmicutes. The plaque microbiota of small breed dogs was found to significantly differ to medium and large breeds and was dominated by species belonging to the Firmicutes.

CONCLUSIONS

The bacterial associations with health, gingivitis and periodontitis were conserved across dogs from the UK, USA, China and Thailand. These bacterial signatures of periodontal health and disease have potential as biomarkers for disease detection.