Giant Faraday rotation in atomically thin semiconductors

Faraday rotation is a fundamental effect in the magneto-optical response of solids, liquids and gases. Materials with a large Verdet constant find applications in optical modulators, sensors and non-reciprocal devices, such as optical isolators. Here, we demonstrate that the plane of polarization of light exhibits a giant Faraday rotation of several degrees around the A exciton transition in hBN-encapsulated monolayers of WSe2 and MoSe2 under moderate magnetic fields. This results in the highest known Verdet constant of -1.9 × 107 deg T-1 cm-1 for any material in the visible regime. Additionally, interlayer excitons in hBN-encapsulated bilayer MoS2 exhibit a large Verdet constant (VIL ≈ +2 × 105 deg T-1 cm-2) of opposite sign compared to A excitons in monolayers. The giant Faraday rotation is due to the giant oscillator strength and high g-factor of the excitons in atomically thin semiconducting transition metal dichalcogenides. We deduce the complete in-plane complex dielectric tensor of hBN-encapsulated WSe2 and MoSe2 monolayers, which is vital for the prediction of Kerr, Faraday and magneto-circular dichroism spectra of 2D heterostructures. Our results pose a crucial advance in the potential usage of two-dimensional materials in ultrathin optical polarization devices.

Structural and biophysical characterization of PadR family protein Rv1176c of Mycobacterium tuberculosis H37Rv

Rv1176c of Mycobacterium tuberculosis H37Rv belongs to the PadR-s1 subfamily of the PadR family of protein. Rv1176c forms a stable dimer in solution. Its stability is characterized by a thermal melting transition temperature (Tm) of 39.4 °C. The crystal structure of Rv1176c was determined at a resolution of 2.94 Å, with two monomers in the asymmetric unit. Each monomer has a characteristic N-terminal winged-helix-turn-helix DNA-binding domain. Rv1176c C-terminal is a coiled-coil dimerization domain formed of α-helices α5 to α7. In the Rv1176c dimer, there is domain-swapping of the C-terminal domain in comparison to other PadR homologs. In the dimer, there is a long inter-subunit tunnel in which different ligands can bind. Rv1176c was found to bind to the promoter region of its own gene with high specificity. M. smegmatis MC2 155 genome lacks homolog of Rv1176c. Therefore, it was used as a surrogate to characterize the functional role of Rv1176c. Expression of Rv1176c in M. smegmatis MC2 155 cells imparted enhanced tolerance towards oxidative stress. Rv1176c expressing M. smegmatis MC2 155 cells exhibited enhanced intracellular survival in J774A.1 murine macrophage cells. Overall, our studies demonstrate Rv1176c to be a PadR-s1 subfamily transcription factor that can moderate the effect of oxidative stress.

Engineering 2D Material Exciton Line Shape with Graphene/h-BN Encapsulation

Control over the optical properties of atomically thin two-dimensional (2D) layers, including those of transition metal dichalcogenides (TMDs), is needed for future optoelectronic applications. Here, the near-field coupling between TMDs and graphene/graphite is used to engineer the exciton line shape and charge state. Fano-like asymmetric spectral features are produced in WS2, MoSe2, and WSe2 van der Waals heterostructures combined with graphene, graphite, or jointly with hexagonal boron nitride (h-BN) as supporting or encapsulating layers. Furthermore, trion emission is suppressed in h-BN encapsulated WSe2/graphene with a neutral exciton red shift (44 meV) and binding energy reduction (30 meV). The response of these systems to electron beam and light probes is well-described in terms of 2D optical conductivities of the involved materials. Beyond fundamental insights into the interaction of TMD excitons with structured environments, this study opens an unexplored avenue toward shaping the spectral profile of narrow optical modes for application in nanophotonic devices.

Prospective Comparative Study of Quality of Life in Bladder Cancer Patients Undergoing Cystectomy or Bladder Preservation

PURPOSE/OBJECTIVE(S)

Health-related Quality of life (HRQOL) may be decisive when different treatments yield comparable survival outcomes. We compared QOL in patients undergoing radical cystectomy with ileal conduit (RCIC) or bladder preservation (BP) with (chemo)radiotherapy for bladder cancer.

MATERIALS/METHODS

Patients with histological diagnosis of bladder cancer, stage T1-T4, N0-N1, M0 with a minimum follow-up of 6 months from the last treatment intervention (RCIC or BP) and alive without disease at the time of QOL assessment were eligible for inclusion. After ethics committee approval, two HRQOL instruments were translated, validated and administered: Bladder cancer index (BCI) for bladder cancer-specific HRQOL, which includes 36 items under three domains - bladder, bowel and sexual function and the EORTC QLQ C30 which includes 30 items under three domains - functional, symptom and global health. The mean QOL scores across various domains and specific questions were compared between the two treatment groups using the independent t-test.

RESULTS

Of the 104 patients enrolled, 56 had RCIC, and 48 received BP, and included 95 (91.3%) males. The median time from treatment completion to QOL assessment was 22 months (IQR 10-56). The median age for the entire cohort was 62 years (IQR 55-68), 65.5 years (IQR 55-71) in BP and 59.5 years (IQR 55-66) in RCIC. Overall, mean BCI urinary scores and bowel scores were high in both groups, with no significant difference in function or bother subdomains between the two groups (Table 1). Overall, BCI sexual scores were low in both the groups but significantly better after BP (BPmean 56.9, RCICmean 41.5, p = 0.01). Mean scores for sexual function BPmean 38.4 and RCIC mean 25 p (0.07) and sexual bother BPmean 81 RCICmean 62 (p 0.02) subdomains. There was no significant difference in EORTC QOL outcomes in functional (BPmean 91.4, RCICmean 88.7 p 0.23), symptom (BPmean 89.8, RCICmean 89, p = 0.68) and global health scale (BPmean 76.8, RCICmean 78.5, p = 0.69) in both groups. On question-wise assessment, the ability to perform an exercise (BPmean 94.2, RCICmean 85, p = 0.06) and urinary leakage at night time (BPmean 91.7, RCICmean 77.6, p = 0.01) were better in the BP group, while scores for blood in the urine (BPmean 89.1, RCICmean 97, p = 0.05) were better in the RCIC group compared to BP.

CONCLUSION

Overall, QOL was good in both groups in the urinary and bowel domains while it was low in the sexual domain. However, bladder preservation performed significantly better in the sexual domain than RCIC.

Study Protocol of the Bladder Adjuvant RadioTherapy (BART) Trial: A Randomised Phase III Trial of Adjuvant Radiotherapy Following Cystectomy in Bladder Cancer

AIMS

To assess the efficacy and safety of adjuvant radiotherapy in patients with high-risk muscle-invasive bladder cancer (MIBC) following radical cystectomy (RC) and chemotherapy.

MATERIALS AND METHODS

The BART (Bladder Adjuvant RadioTherapy) trial is an ongoing multicentric, randomised, phase III trial comparing the efficacy and safety of adjuvant radiotherapy versus observation in patients with high-risk MIBC. The key eligibility criteria include ≥pT3, node-positive (pN+), positive margins and/or nodal yield <10, or, neoadjuvant chemotherapy for cT3/T4/N+ disease. In total, 153 patients will be accrued and randomised, in a 1:1 ratio, to either observation (standard arm) or adjuvant radiotherapy (test arm) following surgery and chemotherapy. Stratification parameters include nodal status (N+ versus N0) and chemotherapy (neoadjuvant chemotherapy versus adjuvant chemotherapy versus no chemotherapy). For patients in the test arm, adjuvant radiotherapy to cystectomy bed and pelvic nodes is planned with intensity-modulated radiotherapy to a dose of 50.4 Gy in 28 fractions using daily image guidance. All patients will follow-up with 3-monthly clinical review and urine cytology for 2 years and subsequently 6 monthly until 5 years, with contrast-enhanced computed tomography abdomen pelvis 6 monthly for 2 years and annually until 5 years. Physician-scored toxicity using Common Terminology Criteria for Adverse Events version 5.0 and patient-reported quality of life using the Functional Assessment of Cancer Therapy - Colorectal questionnaire is recorded pre-treatment and at follow-up.

ENDPOINTS AND STATISTICS

The primary endpoint is 2-year locoregional recurrence-free survival. The sample size calculation was based on the estimated improvement in 2-year locoregional recurrence-free survival from 70% in the standard arm to 85% in the test arm (hazard ratio 0.45) using 80% statistical power and a two-sided alpha error of 0.05. Secondary endpoints include disease-free survival, overall survival, acute and late toxicity, patterns of failure and quality of life.

CONCLUSION

The BART trial aims to evaluate whether contemporary radiotherapy after standard-of-care surgery and chemotherapy reduces pelvic recurrences safely and also potentially affects survival in high-risk MIBC.

Prolonged voluntary wheel running reveals unique adaptations in mdx mice treated with microdystrophin constructs ± the nNOS-binding site

We tested the effects of prolonged voluntary wheel running on the muscle function of mdx mice treated with one of two different microdystrophin constructs. At 7 weeks of age mdx mice were injected with a single dose of AAV9-CK8-microdystrophin with (gene therapy 1, GT1) or without (gene therapy 2, GT2) the nNOS-binding domain and were assigned to one of four gene therapy treated groups: mdxRGT1 (run, GT1), mdxGT1 (no run, GT1), or mdxRGT2 (run,GT2), mdxGT2 (no run, GT2). There were two mdx untreated groups injected with excipient: mdxR (run, no gene therapy) and mdx (no run, no gene therapy). A third no treatment group, Wildtype (WT) received no injection and did not run. mdxRGT1, mdxRGT2 and mdxR performed voluntary wheel running for 52 weeks; WT and remaining mdx groups were cage active. Robust expression of microdystrophin occurred in diaphragm, quadriceps, and heart muscles of all treated mice. Dystrophic muscle pathology was high in diaphragms of non-treated mdx and mdxR mice and improved in all treated groups. Endurance capacity was rescued by both voluntary wheel running and gene therapy alone, but their combination was most beneficial. All treated groups increased in vivo plantarflexor torque over both mdx and mdxR mice. mdx and mdxR mice displayed ∼3-fold lower diaphragm force and power compared to WT values. Treated groups demonstrated partial improvements in diaphragm force and power, with mdxRGT2 mice experiencing the greatest improvement at ∼60% of WT values. Evaluation of oxidative red quadriceps fibers revealed the greatest improvements in mitochondrial respiration in mdxRGT1 mice, reaching WT levels. Interestingly, mdxGT2 mice displayed diaphragm mitochondrial respiration values similar to WT but mdxRGT2 animals showed relative decreases compared to the no run group. Collectively, these data demonstrate that either microdystrophin construct combined with voluntary wheel running increased in vivo maximal muscle strength, power, and endurance. However, these data also highlighted important differences between the two microdystrophin constructs. GT1, with the nNOS-binding site, improved more markers of exercise-driven adaptations in metabolic enzyme activity of limb muscles, while GT2, without the nNOS-binding site, demonstrated greater protection of diaphragm strength after chronic voluntary endurance exercise but decreased mitochondrial respiration in the context of running.

Genotypic capacity of post-anthesis stem reserve mobilization in wheat for yield sustainability under drought and heat stress in the subtropical region

Wheat productivity is severely affected by drought and heat stress conditions worldwide. Currently, stem reserve mobilization (SRM) is receiving increased attention as a trait that can sustain wheat yields under adverse environments. However, the significance of SRM in sustaining wheat yields under drought and heat stress conditions remains uncertain in the tropical climate of Indo-Gangetic Plain region. Therefore, this study aimed to investigate genotypic variations in SRM in wheat and their influence on yield sustainability under drought and heat stress environments. The experiment was designed in an alpha-lattice layout, accommodating 43 genotypes under four simulated environments [timely sown and well irrigated (non-stress); timely sown and water-deficit/drought stress; late-sown and well-irrigated crop facing terminally high temperature; and late-sown and water-deficit stress (both water-deficit and heat stress)]. The water-deficit stress significantly increased SRM (16%-68%, p < 0.01) compared to the non-stress environment, while the heat stress conditions reduced SRM (12%-18%). Both SRM and stem reserve mobilization efficiency exhibited positive correlations with grain weight (grain weight spike^-1) under all three different stress treatments (p < 0.05). Strong positive correlations between stem weight (at 12 days after anthesis) and grain weight were observed across the environments (p < 0.001); however, a significant positive correlation between stem weight and SRM was observed only with stress treatments. Results revealed that the SRM trait could effectively alleviate the impacts of water-deficit stress on yields. However, the SRM-mediated yield protection was uncertain under heat stress and combined water-deficit and heat stress treatments, possibly due to sink inefficiencies caused by high temperature during the reproductive period. Defoliated plants exhibited higher SRM than non-defoliated plants, with the highest increment observed in the non-stress treatment compared to all the stress treatments. Results revealed that wider genetic variability exists for the SRM trait, which could be used to improve wheat yield under drought stress conditions.

Characterizing the metabolomic signature of attention-deficit hyperactivity disorder in twins

Emerging evidence implicate the gut microbiota as a potential susceptibility factor in attention-deficit hyperactivity disorder (ADHD), a common multifactorial neurodevelopmental condition. However, little is known about the biochemical signature of ADHD, including the metabolic contribution of the microbiota via the gut-brain axis, and the relative contribution of genetics and environmental factors. Here, we perform unbiased metabolomic profiling of urine and fecal samples collected from a well-characterized Swedish twin cohort enriched for ADHD (33 ADHD, 79 non-ADHD), using ¹H nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry. Our results highlight sex-specific patterns in the metabolic phenotype of individuals with ADHD. Specifically, the urine profile of males, but not females, with ADHD was characterized by greater excretion of hippurate, a product of microbial-host co-metabolism that can cross the blood-brain-barrier with bioactivity of potential relevance to ADHD. This trans-genomic metabolite was also negatively correlated with IQ in males and was significantly correlated with fecal metabolites associated with gut microbial metabolism. The fecal profile of ADHD individuals was characterized by increased excretion of stearoyl-linoleoyl-glycerol, 3,7-dimethylurate, and FAD and lower amounts of glycerol 3-phosphate, thymine, 2(¹H)-quinolinone, aspartate, xanthine, hypoxanthine, and orotate. These changes were independent of ADHD medication, age, and BMI. Furthermore, our specific twins' models revealed that many of these gut metabolites had a stronger genetic influence than environmental. These findings suggest that metabolic disturbances in ADHD, involving combined gut microbial and host metabolic processes, may largely derive from gene variants previously linked to behavioral symptoms in this disorder.

Proton beam radiotherapy for choroidal and ciliary body melanoma in the UK-national audit of referral patterns of 1084 cases

INTRODUCTION

Proton beam therapy has been utilised for the treatment of uveal melanoma in the UK for over 30 years, undertaken under a single centre. In the UK, all ocular tumours are treated at one of four centres. We aimed to understand the variation in referral patterns to the UK proton service, capturing all uveal melanoma patients treated with this modality.

METHODS

Retrospective analysis of data regarding all patients treated at the Clatterbridge Proton service between January 2004 and December 2014.

RESULTS

A total of 1084 patients with uveal melanoma were treated. The mean age was 57 years (range 9-90 years), basal diameter of 11.5 mm (range 2.0-23.4 mm) and tumour thickness of 3.9 mm (range 0.1-15.4 mm). The majority were TNM stage I (39%) or II (36%). The distance to the optic nerve varied from 0 to 24.5 mm with 148 (14%) of patients having ciliary body involvement. There were variations in the phenotypic characteristic of the tumours treated with protons from different centres, with London referring predominantly small tumours at the posterior pole, Glasgow referring large tumours often at the ciliary body and Liverpool sending a mix of these groups.

DISCUSSION

In the UK, common indications for the use of proton treatment in uveal melanoma include small tumours in the posterior pole poorly accessible for plaque treatment (adjacent to the disc), tumours at the posterior pole affecting the fovea and large anterior tumours traditionally too large for brachytherapy. This is the first UK-wide audit enabling the capture of all patients treated at the single proton centre.

Thrombectomy Outcomes With General vs Nongeneral Anesthesia: A Pooled Patient-Level Analysis From the EXTEND-IA Trials and SELECT Study

BACKGROUND AND OBJECTIVES

The effect of anesthesia choice on endovascular thrombectomy (EVT) outcomes is unclear. Collateral status on perfusion imaging may help identify the optimal anesthesia choice.

METHODS

In a pooled patient-level analysis of EXTEND-IA, EXTEND-IA TNK, EXTEND-IA TNK part II, and SELECT, EVT functional outcomes (modified Rankin Scale score distribution) were compared between general anesthesia (GA) vs non-GA in a propensity-matched sample. Furthermore, we evaluated the association of collateral flow on perfusion imaging, assessed by hypoperfusion intensity ratio (HIR) - Tmax > 10 seconds/Tmax > 6 seconds (good collaterals - HIR < 0.4, poor collaterals - HIR ≥ 0.4) on the association between anesthesia type and EVT outcomes.

RESULTS

Of 725 treated with EVT, 299 (41%) received GA and 426 (59%) non-GA. The baseline characteristics differed in presentation National Institutes of Health Stroke Scale score (median [interquartile range] GA: 18 [13-22], non-GA: 16 [11-20], p < 0.001) and ischemic core volume (GA: 15.0 mL [3.2-38.0] vs non-GA: 9.0 mL [0.0-31.0], p < 0.001). In addition, GA was associated with longer last known well to arterial access (203 minutes [157-267] vs 186 minutes [138-252], p = 0.002), but similar procedural time (35.5 minutes [23-59] vs 34 minutes [22-54], p = 0.51). Of 182 matched pairs using propensity scores, baseline characteristics were similar. In the propensity score-matched pairs, GA was independently associated with worse functional outcomes (adjusted common odds ratio [adj. cOR]: 0.64, 95% CI: 0.44-0.93, p = 0.021) and higher neurologic worsening (GA: 14.9% vs non-GA: 8.9%, aOR: 2.10, 95% CI: 1.02-4.33, p = 0.045). Patients with poor collaterals had worse functional outcomes with GA (adj. cOR: 0.47, 95% CI: 0.29-0.76, p = 0.002), whereas no difference was observed in those with good collaterals (adj. cOR: 0.93, 95% CI: 0.50-1.74, p = 0.82), p interaction: 0.07. No difference was observed in infarct growth overall and in patients with good collaterals, whereas patients with poor collaterals demonstrated larger infarct growth with GA with a significant interaction between collaterals and anesthesia type on infarct growth rate (p interaction: 0.020).

DISCUSSION

GA was associated with worse functional outcomes after EVT, particularly in patients with poor collaterals in a propensity score-matched analysis from a pooled patient-level cohort from 3 randomized trials and 1 prospective cohort study. The confounding by indication may persist despite the doubly robust nature of the analysis. These findings have implications for randomized trials of GA vs non-GA and may be of utility for clinicians when making anesthesia type choice.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that use of GA is associated with worse functional outcome in patients undergoing EVT.

TRIAL REGISTRATION INFORMATION

EXTEND-IA: ClinicalTrials.gov (NCT01492725); EXTEND-IA TNK: ClinicalTrials.gov (NCT02388061); EXTEND-IA TNK part II: ClinicalTrials.gov (NCT03340493); and SELECT: ClinicalTrials.gov (NCT02446587).

Mediation of Successful Reperfusion Effect through Infarct Growth and Cerebral Edema: A Pooled, Patient-Level Analysis of EXTEND-IA Trials and SELECT Prospective Cohort

OBJECTIVE

Reperfusion therapy is highly beneficial for ischemic stroke. Reduction in both infarct growth and edema are plausible mediators of clinical benefit with reperfusion. We aimed to quantify these mediators and their interrelationship.

METHODS

In a pooled, patient-level analysis of the EXTEND-IA trials and SELECT study, we used a mediation analysis framework to quantify infarct growth and cerebral edema (midline shift) mediation effect on successful reperfusion (modified Treatment in Cerebral Ischemia ≥ 2b) association with functional outcome (modified Rankin Scale distribution). Furthermore, we evaluated an additional pathway to the original hypothesis, where infarct growth mediated successful reperfusion effect on midline shift.

RESULTS

A total 542 of 665 (81.5%) eligible patients achieved successful reperfusion. Baseline clinical and imaging characteristics were largely similar between those achieving successful versus unsuccessful reperfusion. Median infarct growth was 12.3ml (interquartile range [IQR] = 1.8-48.4), and median midline shift was 0mm (IQR = 0-2.2). Of 249 (37%) demonstrating a midline shift of ≥1mm, median shift was 2.75mm (IQR = 1.89-4.21). Successful reperfusion was associated with reductions in both predefined mediators, infarct growth (β = -1.19, 95% confidence interval [CI] = -1.51 to -0.88, p < 0.001) and midline shift (adjusted odds ratio = 0.36, 95% CI = 0.23-0.57, p < 0.001). Successful reperfusion association with improved functional outcome (adjusted common odds ratio [acOR] = 2.68, 95% CI = 1.86-3.88, p < 0.001) became insignificant (acOR = 1.39, 95% CI = 0.95-2.04, p = 0.094) when infarct growth and midline shift were added to the regression model. Infarct growth and midline shift explained 45% and 34% of successful reperfusion effect, respectively. Analysis considering an alternative hypothesis demonstrated consistent results.

INTERPRETATION

In this mediation analysis from a pooled, patient-level cohort, a significant proportion (~80%) of successful reperfusion effect on functional outcome was mediated through reduction in infarct growth and cerebral edema. Further studies are required to confirm our findings, detect additional mediators to explain successful reperfusion residual effect, and identify novel therapeutic targets to further enhance reperfusion benefits. ANN NEUROL 2023.

High-Performance Broadband Faraday Rotation Spectroscopy of 2D Materials and Thin Magnetic Films

A Faraday rotation spectroscopy (FRS) technique is presented for measurements on the micrometer scale. Spectral acquisition speeds of about two orders of magnitude faster than state-of-the-art modulation spectroscopy setups are demonstrated. The experimental method is based on charge-coupled-device detection, avoiding speed-limiting components, such as polarization modulators with lock-in amplifiers. At the same time, FRS spectra are obtained with a sensitivity of 20 µrad ( 0.001 ° \[0.001{\bm{^\circ }}\] ) over a broad spectral range (525-800 nm), which is on par with state-of-the-art polarization-modulation techniques. The new measurement and analysis technique also automatically cancels unwanted Faraday rotation backgrounds. Using the setup, Faraday rotation spectroscopy of excitons is performed in a hexagonal boron nitride-encapsulated atomically thin semiconductor WS₂ under magnetic fields of up to 1.4 T at room temperature and liquid helium temperature. An exciton g-factor of -4.4 ± 0.3 is determined at room temperature, and -4.2 ± 0.2 at liquid helium temperature. In addition, FRS and hysteresis loop measurements are performed on a 20 nm thick film of an amorphous magnetic Tb₂₀ Fe₈₀ alloy.

P-138 PREDICTORS OF COMPLICATIONS IN COMPLEX VENTRAL HERNIA REPAIR USING POSTERIOR COMPONENT SEPARATION TECHNIQUE WITH RETRO RECTUS MESH PLACEMENT – AN OBSERVATIONAL STUDY

Introduction

Incisional Hernia has an incidence ranging from 2–20%. Large and complex incisional hernias are difficult to treat with standard procedures. PCS-TAR is a relatively novel procedure. There persists a gap in knowledge regarding its outcomes, especially in the Indian population.

Aims & Objective

To identify the pre-operative clinical and radiological factors that predict the risk of re-herniation and wound and mesh-related complications after CVH (Complex Ventral Hernia)

Methodology

In a prospective observational study, patients undergoing open PCS-TAR with retro rectus mesh for Complex Ventral Hernia repair included in the study. The patient demographics, hernia characteristics, radiological details, operative data, post- operative outcomes, and follow-up data were entered in a pre-designed proforma. Data were analyzed with SPSS softwere.

Results

35 patients with CVH were included, of which 30 (85%) women and 5 men. The mean age was 51.8 years and the mean BMI was 29.7 kg/m2. The mean size of defect was 12 cm. 83% hernia were midline primary and 255 were recurrent hernias. We observed zero recurrences at six months of follow-up, but a high wound morbidity rate of up to 49%, of which most common was seroma formation. 23% of patients developed SSI.

Conclusion

In conclusion, PCS-TAR is a promising novel procedure for complex ventral hernias not amenable to primary closure using the traditional retro rectus approach, with excellent short term outcomes. Wound morbidity is a significant concern with this procedure, which can be prevented or reduced by thorough pre-operative optimization on a case-to-case basis.

O085 CD10 expression in carcinomas of the pancreas, bile duct and ampulla

Introduction

Pancreatic cancer and cholangiocarcinoma including, cancer of ampulla of Vater, are very aggressive and have a dismal prognosis; hence improved methods of patient stratification are required.

Methods

We assessed the expression of CD10 in stromal and epithelial cells of two patient cohorts using immunohistochemistry on tissue microarrays. The first cohort was composed of 68 pancreatic adenocarcinomas and the second cohort was composed of 120 cancers of the bile duct and ampulla.

Results

In bile duct and ampullary carcinomas an association was observed between CD10 stromal expression and patient age (p =0.009). The CD10 stromal expression was associated with poor disease specific survival (DSS) (p =0.05). In multivariate Cox model for DSS, stromal CD10 expression (p = 0.037) was independently associated with poor outcome. In multivariate Cox model for disease free survival (DFS), CD10 stromal expression (p = 0.012), and nodal status (p = 0.025) were independently associated with poor outcome. In pancreatic cancer, no statistically significant association was observed between CD 10 stromal expression and clinicopathological variables such as tumour size (p = 0.099), T stage (p = 0.393), N stage (p = 0.860), Vascular invasion (p = 0.904), perineural invasion (p = 0.532) and grade (0.168). In multivariate Cox model for DSS, T stage (p = 0.042) was independently associated with poor outcome.

Conclusion

The results suggest that CD10 stromal expression may have prognostic significance in cholangiocarcinoma. The findings of this study warrant a larger follow-up study.

Take-home message

The results suggest that CD10 stromal expression may have prognostic significance in cholangiocarcinoma. The findings of this study warrant a larger follow-up study.

Population Impact of Sugar-Sweetened Beverages on Dental Caries and Overweight/Obesity in Australian Children

KNOWLEDGE TRANSFER STATEMENT

The reported findings greatly consolidated evidence of detrimental effects of sugars intake on child oral health and overweight and obesity, some of the most prevalent chronic conditions in children. Evidence on population impact of sugars intake is directly informative to policy makers and the public about the potential impact of population-based programs targeting sugars intake to prevent dental caries and overweight and obesity.

60 Neoadjuvant Imatinib Mesylate – an Ace of Spaces for Surgical Management of an Oesophago-Gastric Junction Gastro-Intestinal Stromal Tumour

Introduction

Oesophageal gastro-intestinal stromal tumours (GISTs) are rare, accounting for less than five percent of all GIST, with the majority of these occurring at the oesophago-gastric junction (OGJ). Due to the anatomical location and size of these tumours at presentation, surgical resection is often a major undertaking.

Neoadjuvant treatment with tyrosine kinase inhibitors, such as Imatinib mesylate, have the potential to downstage such tumours, thereby limiting the extent of subsequent surgical resection. This may therefore reduce any potentially associated morbidity and mortality.

Case Description

We report the case of a 75-year-old gentleman who presented with a large OGJ GIST, which presented with dysphagia. The tumour was deemed too large for local excision due to the risk of compromising the lumen at the OGJ in attempting to obtain a clear resection margin. Given the patient’s co-morbidity, oesophagectomy or total gastrectomy was deemed too major an undertaking. Therefore, endoscopic biopsies were obtained with a view to possible neoadjuvant therapy. These confirmed DOG-1 and Exon-11 mutations, suggesting sensitivity to Imatinib mesylate. A standard dose regime of 400mg daily for a planned 36-month course was commenced. Subsequent imaging showed a substantial decrease in tumour bulk and the decision was made to perform a local excision. A local enucleation procedure was performed, and the patient made a sound recovery.

Post-operative histology of resected tumour showed almost complete tumour regression.

Discussion

This significant response to neoadjuvant Imatinib mesylate therapy demonstrates clear potential for its use in similar cases, where radical resection would cause significant morbidity and risk mortality.

Thrombolysis for stroke in elderly in the late window period

OBJECTIVES

Safety of intravenous thrombolysis (IVT) within 3-4.5 hours of stroke onset in patients ≥80 years is still disputable. We evaluated the association of symptom onset-to-treatment time (SOTT) with the symptomatic intracranial hemorrhage (sICH), poor outcome, and mortality in patients≥80 years.

MATERIALS AND METHODS

In a retrospective study, patients treated with IVT following stroke were registered. Outcomes were poor outcome (mRS>2), sICH/ECASS-2, and in-hospital mortality. We compared the patients≥80 years who received IVT within 3 hours with those receiving IVT within 3-4.5 hours. We further compared the patients who were <80 years with those ≥80 years and SOTT of 3-4.5 hours.

RESULTS

Of 834 patients, 265 aged over 80. In those above 80 and in multivariable analysis, the associations of SOTT with poor outcome (aOR: 1.401, CI: 0.503-3.903, p=0.519), sICH (aOR=2.50, CI=0.76-8.26, p= 0.132) and mortality (aOR=1.12, CI=0.39-3.25, p= 0.833) were not significant. 106 patients received IVT within 3-4.5 hours. In multivariable analysis, the associations of age (≥80 versus <80) with poor outcome (aOR=1.87, CI=0.65-5.37, p=0.246), sICH (aOR=0.65, CI=0.14-3.11, p=0.590), and mortality (aOR=0.87, 95% CI=0.16-4.57, p=0.867) were not significant in patients with SOTT of 3-4.5 hours.

CONCLUSION

IVT within 3-4.5 hours in patients ≥80 years is not associated with increased sICH, poor outcome, and mortality compared to the early time window, and also compared to the younger patients in 3-4.5 hours window period. The decision of IVT administration in this age group should not be made solely on the basis of stroke onset timing.

"Watch Me Grow- Electronic (WMG-E)" surveillance approach to identify and address child development, parental mental health, and psychosocial needs: study protocol

Background

The COVID-19 pandemic and the associated economic recession has increased parental psychosocial stress and mental health challenges. This has adversely impacted child development and wellbeing, particularly for children from priority populations (culturally and linguistically diverse (CALD) and rural/regional communities) who are at an already increased risk of health inequality. The increased mental health and psychosocial needs were compounded by the closure of in-person preventive and health promotion programs resulting in health organisations embracing technology and online services. Watch Me Grow- Electronic (WMG-E) – developmental surveillance platform- exemplifies one such service.

WMG-E was developed to monitor child development and guide parents towards more detailed assessments when risk is identified. This Randomised Controlled Trial (RCT) aims to expand WMG-E as a digital navigation tool by also incorporating parents’ mental health and psychosocial needs. Children and families needing additional assessments and supports will be electronically directed to relevant resources in the ‘care-as-usual’ group. In contrast, the intervention group will receive continuity of care, with additional in-person assessment and ‘warm hand over’ by a ‘service navigator’ to ensure their needs are met.

Methods

Using an RCT we will determine: (1) parental engagement with developmental surveillance; (2) access to services for those with mental health and social care needs; and (3) uptake of service recommendations. Three hundred parents/carers of children aged 6 months to 3 years (recruited from a culturally diverse, or rural/regional site) will be randomly allocated to the ‘care-as-usual’ or ‘intervention’ group. A mixed methods implementation evaluation will be completed, with semi-structured interviews to ascertain the acceptability, feasibility and impact of the WMG-E platform and service navigator.

Conclusions

Using WMG-E is expected to: normalise and de-stigmatise mental health and psychosocial screening; increase parental engagement and service use; and result in the early identification and management of child developmental needs, parental mental health, and family psychosocial needs. If effective, digital solutions such as WMG-E to engage and empower parents alongside a service navigator for vulnerable families needing additional support, will have significant practice and policy implications in the pandemic/post pandemic period.

Trial registration

The trial (Protocol No. 1.0, Version 3.1) was registered with ANZCTR (registration number: ACTRN12621000766819) on July 21st, 2021 and reporting of the trial results will be according to recommendations in the CONSORT Statement.

Validation of an obstetric quality of recovery scoring tool (ObsQoR-11) after elective caesarean delivery in a developing country: a prospective observational study

BACKGROUND

The obstetric quality of recovery scoring tool (ObsQoR-11) was developed and validated in the United Kingdom for use after elective and emergency caesarean delivery. Quality of recovery scoring tools validated in one country may not be valid in other countries with significant cultural, socio-economic and linguistic variations. The aim of the current study was to validate a Hindi version of the ObsQoR-11.

METHODS

In this prospective observational study, 100 parturients who underwent elective caesarean delivery in a tertiary care obstetric referral university hospital in North India were asked to complete a Hindi version of the ObsQoR-11 scoring tool 24 h after surgery. The performance of the Hindi version of ObsQoR-11 was assessed using measures of validity, reliability, and feasibility.

RESULTS

The Hindi version of ObsQoR-11 correlated moderately with the global health visual analogue scale (r=0.45, 95% CI 0.27 to 0.59; P <0.0001) and discriminated well between good and poor recovery (mean (SD) score 84.6 (9.4) vs 75.0 (11.2); P <0.0001). The reliability and internal consistency were moderate (Cronbach's alpha=0.66; Spearman-Brown Prophesy Reliability estimate=0.57) with good repeatability (intraclass correlation coefficient 0.85, 95% CI 0.69 to 0.93; P <0.0001) and no floor or ceiling effects. All parturients completed the questionnaire (median (IQR) time of completion of 3 (1.5 - 5.5) min).

CONCLUSION

The Hindi version of the ObsQoR-11 questionnaire is a promising scoring tool to evaluate quality of recovery after elective caesarean delivery. Further research is needed to evaluate the Hindi tool in other institutions in India, as well as in other languages.

1300 Version Abnormalities of the Femur and Acetabulum in Patients with Femoroacetabular Impingement: A Systematic Review

Aim

This systematic review aims to understand the relationship between version abnormalities of the femur and acetabulum in patients with primary and secondary femoroacetabular impingement (FAI).

Method

A systematic review was conducted according to PRISMA guidelines. A computer-based search was performed using the EMBASE, MEDLINE, PubMed and Cochrane databases for articles relating to version and torsional abnormalities in FAI, Legg-Calve-Perthes disease (LCPD) and slipped capital femoral epiphysis (SCFE). The study was registered in the Open Science Framework. Two authors independently performed title/abstract and full text screening according to predetermined inclusion criteria.

Results

A total of 1206 articles were identified 55 articles, involving 10, 091 hips, met the inclusion criteria. All studies evaluating femoral/acetabular version in FAI reported ‘normal’ mean version values (10o to 25o). However, distribution analysis revealed that an estimated 31.4% and 51.3% of patients with FAI displayed abnormal acetabular and femoral version, respectively. Abnormal femoral version was reported in an estimated 74.5% of hips with LCPD, and abnormal acetabular version in an estimated 20%. Acetabular version was significantly lower in hips with SCFE compared to controls (Z=-3.26, P &lt; 0.01).

Conclusions

Patients presenting with hip pain attributed to FAI are likely to display an abnormality in femoral or acetabular version. This highlights the importance of evaluating these parameters during assessment of these patients, in order to guide clinical decision making.

283 Salvage Versus Primary Robot-Assisted Radical Prostatectomy: A Propensity-Matched Comparative Effectiveness Study from A High-Volume Tertiary Centre

Aim

Salvage Robot-Assisted Radical Prostatectomy (sRARP) is a potential treatment option for locally recurrent Prostate Cancer after non-surgical primary treatment. There are minimal data comparing outcomes between propensity-matched salvage and primary Robot-Assisted Radical Prostatectomy (RARP). We compare perioperative, oncological, and functional outcomes of sRARP with primary RARP and between sRARP post-whole and focal gland therapy.

Method

1:1 propensity-matched comparison of 146 sRARP with primary RARP from a cohort of 3,852 consecutive patients from a high-volume tertiary centre.

Results

There were no significant differences in patient characteristics between the salvage and primary RARP groups. Grade III-V Clavien-Dindo complication rates were 1.3% and 0% in the salvage and primary groups, respectively (p = 0.310). Median (IQR) follow-up was 16 (10,30) and 21 (13,33) months in the salvage and primary groups, respectively. BCR rates were 30.8% and 13.7% in the salvage and primary groups, respectively (p &lt; 0.001). Pad-free continence rates were 79.1% and 85.4% at two years in the salvage and primary groups, respectively (p = 0.160). ED rates were 95.2% and 77.4% in the salvage and primary groups, respectively (p &lt; 0.001). Comparing the whole gland and focal gland groups, BCR rates were 33.3% and 29.1%, respectively (p = 0.687), pad-free continence rates were 66% and 89.3%, respectively (p = 0.001), and ED rates were 98.3% and 93%, respectively (p = 0.145).

Conclusions

SRARP has similar perioperative but inferior oncological outcomes to primary RARP. Continence rates are similar to primary RARP, but potency is worse. Perioperative and oncological outcomes of sRARP after focal gland therapy are similar but continence outcomes are superior compared to sRARP after whole gland therapy.

1124 Is Delayed Presentation A Prognostic Factor for The Survival of Patients with Esophageal Atresia More Than Associated Anomalies? Comparison Between Different Social Realities

Background

The aim is to evaluate if different social reality could represent a prognostic factor as associated anomalies affecting survival of neonates with esophageal atresia (EA).

Method

Retrospective analysis of records of neonates with EA with or without Tracheoesophageal Fistula (TEF) from January 2011 to September 2018 at Policlinico San Matteo Pavia, Italy(SMAT) and the All India Institute of Medical Sciences New Delhi, India (AIIMS).Survival was correlated with the presence of anomalies, different types and the number of organ systems involved.Age at presentation and birth weight were considered to find an association with mortality.

Results

Out of 180 patients,162 were from AIIMS and 18 from SMAT.The overall mortality was 28.85%, which occurred at AIIMS, being 0% at SMAT.83.33% at SMAT and 72.84% at AIIMS had associated anomalies.The mortality was 25% for neonates without an anomaly, being 26.15% for those with one (p &gt; 0.05).No statistically significant correlation between outcome and associated anomalies was found.Instead, survival declines gradually as the age at presentation increases.

Conclusions

The presence of associated anomalies paradoxically does not affect the outcome because incidence of delayed presentation has a stronger effect than the presence of associated anomalies. Sensibilization is necessary to improve survival in EA neonates in developing countries, such as India.

1079 Analysis of Human Papilloma Virus (HPV) Status in Metastatic Oropharyngeal Squamous Cell Carcinoma (OPSCC)

Introduction

OPSCC often (80%) presents with ipsilateral neck metastasis. Presentation may be as carcinoma of unknown primary (CUP). Sampling via ultrasound guided Fine Needle Aspiration Cytology (FNAC) and/or Core Biopsy (CB) from nodal metastases is required for diagnosis, comparison with primary tumour and to assess human papilloma virus (HPV) status. HPV positive biopsy from CUP may indicate oropharynx primary. HPV positive OPSCC has better prognosis. HPV association is ascertained by p16 immunocytochemistry (p16- IHC) and HPV DNA in situ hybridization (HPV-ISH). In a cohort of OPSCC patients from a single referral centre 68% had metastatic disease. Core biopsy was optimal for HPV testing.

Method

Retrospective review of records from Transoral Robotic Surgery (TORS) patients treated for OPSCC between December 2017-2019 was conducted. Cohort included patients undergoing TORS for diagnostic purposes and with curative intent.

Results

Data was available from 23 patients who had TORS for OPSCC. 47.8% (n = 11) presented with lymphadenopathy. 82.6% (n = 19) underwent FNAC. 68.4% (n = 13) were diagnosed with metastatic OPSCC and 56.5% (n = 13) underwent neck dissections. 52.2% (n = 12) had confirmed HPV positive metastases, 75% (n = 9) had 1 node positive, 25% (n = 3) had &gt;1 node positive. FNAC yielded enough tissue for p16 IHC and HPV-ISH in 10.5% (n = 2). CB yielded sufficient tissue for analysis in all cases 39.1% (n = 9).

Conclusions

The study confirms high incidence of neck metastases in HPV associated OPSCC patients. Needle core biopsy appears superior to FNAC for tissue sampling to assess HPV status in tumours metastatic to neck.

1692 No Longer Unknown: A Systematic Review & Meta-Analysis of The Effectiveness of Trans-Oral Surgical Techniques in Identifying Head and Neck Primary Cancer in Carcinoma Unknown Primary

Aim

The use of transoral robotic surgery (TORS), transoral laser microsurgery (TLM) and more recently reported transoral endoscopic electrocautery (TOEC) in the identification of the primary cancer in CUP patients has gained popularity. This systematic review aims to assess the effectiveness of TORS, TLM and TOEC.

Method

A systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting methodology was carried out to assess the effectiveness of the three trans-oral surgical techniques. EMBASE, MEDLINE and CINAHL databases were searched from inception to September 2020. Primary outcome measure was detection rates of primary cancer of the different techniques. Secondary outcome measures were complications and length of hospital stay.

Results

289 studies were identified of which 30 met the inclusion criteria (28 case series and 2 case reports). The overall combined primary identification rate was 72.3% (567 /777 patients). The primary identification rates were 49.7% and 34.2% in lingual (n = 273) and palatine tonsillectomy (n = 118) respectively. The primary cancer identification rates by surgical techniques are: TORS was 60% (CI 0.49, 0.70), TLM was 80% (CI 0.58, 1.01), TOEC was 41% (CI 0.05, 0.76). The commonest complication was haemorrhage (5.3%).

Conclusions

This is the largest systematic review in the subject and incorporates the more recently published surgical technique of TOEC. Lingual tonsillectomy is an effective procedure in CUP work up. Further larger, multi-centre, prospective studies of PET CT negative CUP patients is needed to draw conclusive results

Snapshots Quiz

A 55-year-old male presented with a 6 month history of multiple swellings on the right buttock and sacral region with yellowish discharge. The patient frequently walked bare foot, but denied any history trauma. Fine needle aspirate cytology showed acute dense inflammation, nuclear debris and numerous filamentous bacilli, which on staining revealed gram positive bacilli. What is the diagnosis?

Modified vertical osteotomy cut in bilateral sagittal split osteotomy

Bilateral sagittal split osteotomy (BSSO) is the most common orthognathic surgical procedure for the correction of facial deformities. Like any other surgical procedure, it is also associated with a risk of complications. One of these is described in the literature as notching at the lower inferior border of the mandible. Such discontinuity in the contour of the lower border is often a concern for patients. To overcome this complication, we recommend a modified vertical osteotomy cut while performing BSSO.

Is HRCT reliable in determining disease activity in pulmonary tuberculosis?

Aims and Objectives The purpose of our study is to [1] determine the activity of disease based on the HRCT findings (2) to define indications for the use of HRCT in evaluation of Pulmonary TB and (3) to determine whether additional information provided by HRCT alters clinical management of the disease. Materials and Methods The present study was carried out at Shree Sayajirao General Hospital (SSGH), Baroda, Gujarat, India from January 2002 to December 2002. Twenty five patients with sputum positive post-primary pulmonary TB were studied prospectively with chest radiographs and HRCT. The diagnosis of active TB was based on detection of acid-fast bacilli in sputum. None of the patients in our study population was HIV positive. All patients underwent x-ray chest and HRCT chest (Philips Tomoscan, Best, Netherlands). The pattern, extent and severity of HRCT findings were recorded and compared with the plain x-ray findings. The gathered information and investigations were subjected to statistical analysis. Results Our study population consisted of sputum positive (AFB positive) 25 patients, 22 of them were newly diagnosed/suspected post-primary tuberculosis (GROUP 1) and 3 of them had taken six months of AKT (GROUP 2). Our study included 22 males and 3 females with average age of 38 years (range, 14-65 years.) In total chest radiographic signs of active tuberculosis were seen in twelve (48%) patients. HRCT showed evidences of active tuberculosis in all 22 patients of newly diagnosed tuberculosis; and in 2 out of 3 patients with prior history of AKT. Thus, total of 24 (96%) patients had evidence of active pulmonary TB on HRCT. One patient with prior history of AKT showed evidence of pulmonary Koch′s sequel. Conclusion Although chest radiography remains the foremost imaging technique in the evaluation of pulmonary TB, HRCT can be useful in certain circumstances and can provide important information in the diagnosis and management of the disease. HRCT is helpful in the distinction of active form inactive TB. HRCT is better than plain chest radiograph in identification of extent of pulmonary TB, especially subtle areas of consolidation, cavitation, bronchogenic and miliary spread. HRCT is recommended when the radiographic findings are normal or inconclusive and tuberculosis is suspected clinically for the confirmation of diagnosis and determination of activity.

Clinical and Neuroimaging Outcomes of Direct Thrombectomy vs Bridging Therapy in Large Vessel Occlusion: Analysis of the SELECT Cohort Study

OBJECTIVE

To evaluate the comparative safety and efficacy of direct endovascular thrombectomy (dEVT) compared to bridging therapy (BT; IV tissue plasminogen activator + EVT) and to assess whether BT potential benefit relates to stroke severity, size, and initial presentation to EVT vs non-EVT center.

METHODS

In a prospective multicenter cohort study of imaging selection for endovascular thrombectomy (Optimizing Patient Selection for Endovascular Treatment in Acute Ischemic Stroke [SELECT]), patients with anterior circulation large vessel occlusion (LVO) presenting to EVT-capable centers within 4.5 hours from last known well were stratified into BT vs dEVT. The primary outcome was 90-day functional independence (modified Rankin Scale [mRS] score 0-2). Secondary outcomes included a shift across 90-day mRS grades, mortality, and symptomatic intracranial hemorrhage. We also performed subgroup analyses according to initial presentation to EVT-capable center (direct vs transfer), stroke severity, and baseline infarct core volume.

RESULTS

We identified 226 LVOs (54% men, mean age 65.6 ± 14.6 years, median NIH Stroke Scale [NIHSS] score 17, 28% received dEVT). Median time from arrival to groin puncture did not differ in patients with BT when presenting directly (dEVT 1.43 [interquartile range (IQR) 1.13-1.90] hours vs BT 1.58 [IQR 1.27-2.02] hours, p = 0.40) or transferred to EVT-capable centers (dEVT 1.17 [IQR 0.90-1.48] hours vs BT 1.27 [IQR 0.97-1.87] hours, p = 0.24). BT was associated with higher odds of 90-day functional independence (57% vs 44%, adjusted odds ratio [aOR] 2.02, 95% confidence interval [CI] 1.01-4.03, p = 0.046) and functional improvement (adjusted common OR 2.06, 95% CI 1.18-3.60, p = 0.011) and lower likelihood of 90-day mortality (11% vs 23%, aOR 0.20, 95% CI 0.07-0.58, p = 0.003). No differences in any other outcomes were detected. In subgroup analyses, patients with BT with baseline NIHSS scores <15 had higher functional independence likelihood compared to those with dEVT (aOR 4.87, 95% CI 1.56-15.18, p = 0.006); this association was not evident for patients with NIHSS scores ≥15 (aOR 1.05, 95% CI 0.40-2.74, p = 0.92). Similarly, functional outcomes improvements with BT were detected in patients with core volume strata (ischemic core <50 cm3: aOR 2.10, 95% CI 1.02-4.33, p = 0.044 vs ischemic core ≥50 cm3: aOR 0.41, 95% CI 0.01-16.02, p = 0.64) and transfer status (transferred: aOR 2.21, 95% CI 0.93-9.65, p = 0.29 vs direct to EVT center: aOR 1.84, 95% CI 0.80-4.23, p = 0.15).

CONCLUSIONS

BT appears to be associated with better clinical outcomes, especially with milder NIHSS scores, smaller presentation core volumes, and those who were "dripped and shipped." We did not observe any potential benefit of BT in patients with more severe strokes.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT02446587.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with ischemic stroke from anterior circulation LVO within 4.5 hours from last known well, BT compared to dEVT leads to better 90-day functional outcomes.

A65 ENDOSCOPIST-TARGETED INTERVENTIONS TO OPTIMIZE ADENOMA DETECTION RATE - A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Adenoma detection rate (ADR) has emerged as the strongest quality assurance metric that has consistently been shown to be inversely associated with the development of colorectal cancer after colonoscopy. Unfortunately, marked variability in ADR exists among endoscopists. A multitude of interventions targeted at endoscopists to optimize their ADR have been reported, including but not limited to withdrawal time, in room observers, physician report cards, and quality improvement and training programs. However, it is unclear which of them are truly effective.

Aims

We performed a systematic review and meta-analysis of the literature to evaluate the effectiveness of endoscopist-targeted interventions to improve adenoma detection rate (ADR) or polyp detection rate (PDR).

Methods

Systematic searches of major databases were conducted through to March 2018 to identify potentially relevant studies. Both randomized controlled trials and observational studies were included. Data for ADR and PDR were analyzed on the log-odds scale using a random-effects meta-analysis model using restricted maximum likelihood (with Mantel-Haenszel fixed-effect meta-analysis used for fewer than 4 studies). Statistical effect-size heterogeneity was assessed using a Chi2 test and quantifying the relative proportion of variation using the I2 statistic. Publication bias was assessed by the Harbord regression test.

Results

From 4299 initial studies, 24 were included in the systematic review and 13 were included in the meta-analysis representing a total of 55,090 colonoscopies. Physician report card interventions (7 studies) and withdrawal time focused interventions (6 studies) were meta-analyzed. The pooled odds ratio for ADR for report card interventions was 1.31 (95% CI: 1.15, 1.50; p&lt;0.0001), favoring report cards to detect more adenomas. Statistical heterogeneity was detected with substantial relative effect-size variability (Chi2, p&lt;0.0001; I2=80.1%). No statistical evidence of publication bias was found. 6 studies reported data for PDR using withdrawal time focused interventions, with 3 of these reporting data on ADR. The pooled odds ratio for ADR was 1.02 (95% CI: 0.86, 1.22; p=0.81) and for PDR was 1.07 (95% CI: 0.88, 1.31; p=0.51) which were not statistically significant. Statistical heterogeneity was detected in both groups (Chi2, p&lt;0.001; I2=82.2% for ADR and I2=89.4% for PDR) and there was statistical evidence of publication bias. Figures 1 and 2 represent Forest plots for the effect of pre-and post-report card and withdrawal time focused interventions on ADR.

Conclusions

Our study provides evidence that the distribution of colonoscopy quality report cards to physicians significantly improves overall ADR and should strongly be considered as part of quality improvement programs aimed at optimizing colonoscopy performance.

Funding Agencies

None

Immunological characterization of chimeras of high specificity antigens from Mycobacterium tuberculosis H37Rv

Tuberculosis remains a serious global health problem. BCG is the only prophylactic TB vaccine and it shows variable protective efficacy. Chimeric protein subunit vaccines hold great potential as stand-alone vaccines or heterologous BCG prime boosters. We have designed a protein chimera, PP31, by combining Mtb ESAT-6 family antigen Rv1198 and MoCo biosynthesis family antigen Rv3111. Further, PP31 was extended by addition of latency antigen Rv1813c to yield PP43. Immunization of BALB/c mice with PP31 or PP43 with FIA adjuvant elicited strong humoral immune response. Restimulation of splenocytes of the immunized mice lead to significant proliferation of lymphocytes, secretion of cytokines IFN-γ, TNF, IL-2 of the Th1 class, IL-17A of the Th17 class, and IL-6. PP31 and PP43 also induced intracellular cytokine expression (IFN-γ, TNF, and IL-2) from both CD4+-CD44high and CD8+-CD44high T-cells. Antigen-specific IFN-γ+/IL-2+ double positive CD4+ T-cells were significantly higher in case of PP43 than PP31-immunized mice and control group. PP43 showed protection equivalent to heat-inactivated BCG in response to challenge of the immunized mice with Mtb H37Ra. Based on its immunogenicity and protective efficacy, PP43 appears to be a potential candidate for further development as a subunit vaccine against TB.

Early Infarct Growth Rate Correlation With Endovascular Thrombectomy Clinical Outcomes: Analysis From the SELECT Study

BACKGROUND AND PURPOSE

Time elapsed from last-known well (LKW) and baseline imaging results are influential on endovascular thrombectomy (EVT) outcomes.

METHODS

In a prospective multicenter cohort study of imaging selection for endovascular thrombectomy (SELECT [Optimizing Patient's Selection for Endovascular Treatment in Acute Ischemic Stroke], the early infarct growth rate (EIGR) was defined as ischemic core volume on perfusion imaging (relative cerebral blood flow<30%) divided by the time from LKW to imaging. The optimal EIGR cutoff was identified by maximizing the sum of the sensitivity and specificity to correlate best with favorable outcome and to improve its the predictability. Patients were stratified into slow progressors if EIGR<cutoff and fast progressors if EIGR≥the optimal cutoff. Good collaterals were defined on computed tomography perfusion as a hypoperfusion intensity ratio <0.4 and on computed tomography angiography as collateral score >2. The primary outcome was 90-day functional independence (modified Rankin Scale score =0-2).

RESULTS

Of 445 consented, 361 (285 EVT, 76 medical management only) patients met the study inclusion criteria. The optimal EIGR was <10 mL/h; 200 EVT patients were slow and 85 fast progressors. Fast progressors had a higher median National Institutes of Health Stroke Scale (19 versus 15, P<0.001), shorter time from LKW to groin puncture (180 versus 266 minutes, P<0.001). Slow progressors had better collaterals on computed tomography perfusion: hypoperfusion intensity ratio (adjusted odds ratio [aOR]: 5.11 [2.43-10.76], P<0.001) and computed tomography angiography: collaterals-score (aOR: 4.43 [1.83-10.73], P=0.001). EIGR independently correlated with functional independence after EVT, adjusting for age, National Institutes of Health Stroke Scale, time LKW to groin puncture, reperfusion (modified Thrombolysis in Cerebral Infarction score of ≥2b), IV-tPA (intravenous tissue-type plasminogen activator), and transfer status (aOR: 0.78 [0.65-0.94], P=0.01). Slow progressors had higher functional independence rates (121 [61%] versus 30 [35%], P<0.001) and had 3.5 times the likelihood of achieving modified Rankin Scale score =0-2 with EVT (aOR=2.94 [95% CI, 1.53-5.61], P=0.001) as compared to fast progressors, who had substantially worse clinical outcomes both in early and late time window. The odds of good outcome decreased by 14% for each 5 mL/h increase in EIGR (aOR, 0.87 [0.80-0.94], P<0.001) and declined more rapidly in fast progressors.

CONCLUSIONS

The EIGR strongly correlates with both collateral status and clinical outcomes after EVT. Fast progressors demonstrated worse outcomes when receiving EVT beyond 6 hours of stroke onset as compared to those who received EVT within 6 hours. Registration: URL: https://clinicaltrials.gov. Unique identifier: NCT02446587.

Safety and outcomes of percutaneous tracheostomy in coronavirus disease 2019 pneumonitis patients requiring prolonged mechanical ventilation

OBJECTIVES

Tracheostomy for coronavirus disease 2019 pneumonitis patients requiring prolonged invasive mechanical ventilation remains a matter of debate. This study analysed the timing and outcomes of percutaneous tracheostomy, and reports our experience of a dedicated ENT-anaesthetics department led tracheostomy team.

METHOD

A prospective single-centre observational study was conducted of patients undergoing tracheostomy, who had been diagnosed with coronavirus disease 2019 pneumonitis, between 21st March and 20th May 2020.

RESULTS

Eighty-one patients underwent tracheostomy after a median (interquartile range) of 16 (13-20) days of invasive mechanical ventilation. Median follow-up duration was 32 (23-40) days. Of patients, 86.7 per cent were successfully liberated from invasive mechanical ventilation in a median (interquartile range) of 12 (7-16) days. Moreover, 68.7 per cent were subsequently discharged from hospital. On univariate analysis, there was no difference in outcomes between early (before day 14) and late (day 14 or later) tracheostomy. The mortality rate was 8.6 per cent and no deaths were tracheostomy related.

CONCLUSION

Outcomes appear favourable when patients are carefully selected. Percutaneous tracheostomy performed via a multidisciplinary approach, with appropriate training, was safe and optimised healthcare resource utilisation.

Impact of a Positive Viral Polymerase Chain Reaction on Outcomes of Chronic Obstructive Pulmonary Disease (COPD) Exacerbations

Introduction: More than 15 million adults in the USA have chronic obstructive pulmonary disease. Chronic obstructive pulmonary disease (COPD) places a high burden on the healthcare system. Many hospital admissions are due to an exacerbation, which is suspected to be from a viral cause. The purpose of this analysis was to compare the outcomes of patients with a positive and negative respiratory virus panel who were admitted to the hospital with COPD exacerbations. Methods: This retrospective cohort study was conducted in the Geisinger Healthcare System. The dataset included 2729 patient encounters between 1 January 2006 and 30 November 2017. Hospital length of stay was calculated as the discrete number of calendar days a patient was in the hospital. Patient encounters with a positive and negative respiratory virus panel were compared using Pearson’s chi-square or Fisher’s exact test for categorical variables and Student’s t-test or Wilcoxon rank-sum tests for continuous variables. Results: There were 1626 patients with a total of 2729 chronic obstructive pulmonary disease exacerbation encounters. Nineteen percent of those encounters (n = 524) had a respiratory virus panel performed during their admission. Among these encounters, 161 (30.7%) had positive results, and 363 (69.3%) had negative results. For encounters with the respiratory virus panel, the mean age was 64.5, 59.5% were female, 98.9% were white, and the mean body mass index was 26.6. Those with a negative respiratory virus panel had a higher median white blood cell count (11.1 vs. 9.9, p = 0.0076). There were no other statistically significant differences in characteristics between the two groups. Respiratory virus panel positive patients had a statistically significant longer hospital length of stay. There were no significant differences with respect to being on mechanical ventilation or ventilation-free days. Conclusion: This study shows that a positive respiratory virus panel is associated with increased length of hospital stay. Early diagnosis of chronic obstructive pulmonary disease exacerbation patients with positive viral panel would help identify patients with a longer length of stay.

Crystal structure of the GDP-bound GTPase domain of Rab5a from Leishmania donovani

Eukaryotic Rab5s are highly conserved small GTPase-family proteins that are involved in the regulation of early endocytosis. Leishmania donovani Rab5a regulates the sorting of early endosomes that are involved in the uptake of essential nutrients through fluid-phase endocytosis. Here, the 1.80 Å resolution crystal structure of the N-terminal GTPase domain of L. donovani Rab5a in complex with GDP is presented. The crystal structure determination was enabled by the design of specific single-site mutations and two deletions that were made to stabilize the protein for previous NMR studies. The structure of LdRab5a shows the canonical GTPase fold, with a six-stranded central mixed β-sheet surrounded by five α-helices. The positions of the Switch I and Switch II loops confirm an open conformation, as expected in the absence of the γ-phosphate. However, in comparison to other GTP-bound and GDP-bound homologous proteins, the Switch I region traces a unique disposition in LdRab5a. One magnesium ion is bound to the protein at the GTP-binding site. Molecular-dynamics simulations indicate that the GDP-bound structure exhibits higher stability than the apo structure. The GDP-bound LdRab5a structure presented here will aid in efforts to unravel its interactions with its regulators, including the guanine nucleotide-exchange factor, and will lay the foundation for a structure-based search for specific inhibitors.