Multi-omics Analysis Reveals Immune Features Associated with Immunotherapy Benefit in Patients with Squamous Cell Lung Cancer from Phase III Lung-MAP S1400I Trial

PURPOSE

Identifying molecular and immune features to guide immune checkpoint inhibitor (ICI)-based regimens remains an unmet clinical need.

EXPERIMENTAL DESIGN

Tissue and longitudinal blood specimens from phase III trial S1400I in patients with metastatic squamous non-small cell carcinoma (SqNSCLC) treated with nivolumab monotherapy (nivo) or nivolumab plus ipilimumab (nivo+ipi) were subjected to multi-omics analyses including multiplex immunofluorescence (mIF), nCounter PanCancer Immune Profiling Panel, whole-exome sequencing, and Olink.

RESULTS

Higher immune scores from immune gene expression profiling or immune cell infiltration by mIF were associated with response to ICIs and improved survival, except regulatory T cells, which were associated with worse overall survival (OS) for patients receiving nivo+ipi. Immune cell density and closer proximity of CD8+GZB+ T cells to malignant cells were associated with superior progression-free survival and OS. The cold immune landscape of NSCLC was associated with a higher level of chromosomal copy-number variation (CNV) burden. Patients with LRP1B-mutant tumors had a shorter survival than patients with LRP1B-wild-type tumors. Olink assays revealed soluble proteins such as LAMP3 increased in responders while IL6 and CXCL13 increased in nonresponders. Upregulation of serum CXCL13, MMP12, CSF-1, and IL8 were associated with worse survival before radiologic progression.

CONCLUSIONS

The frequency, distribution, and clustering of immune cells relative to malignant ones can impact ICI efficacy in patients with SqNSCLC. High CNV burden may contribute to the cold immune microenvironment. Soluble inflammation/immune-related proteins in the blood have the potential to monitor therapeutic benefit from ICI treatment in patients with SqNSCLC.

Spatial modelling of the tumor microenvironment from multiplex immunofluorescence images: methods and applications

Spatial modelling methods have gained prominence with developments in high throughput imaging platforms. Multiplex immunofluorescence (mIF) provides the scope to examine interactions between tumor and immune compartment at single cell resolution using a panel of antibodies that can be chosen based on the cancer type or the clinical interest of the study. The markers can be used to identify the phenotypes and to examine cellular interactions at global and local scales. Several translational studies rely on key understanding of the tumor microenvironment (TME) to identify drivers of immune response in immunotherapy based clinical trials. To improve the success of ongoing trials, a number of retrospective approaches can be adopted to understand differences in response, recurrence and progression by examining the patient's TME from tissue samples obtained at baseline and at various time points along the treatment. The multiplex immunofluorescence (mIF) technique provides insight on patient specific cell populations and their relative spatial distribution as qualitative measures of a favorable treatment outcome. Spatial analysis of these images provides an understanding of the intratumoral heterogeneity and clustering among cell populations in the TME. A number of mathematical models, which establish clustering as a measure of deviation from complete spatial randomness, can be applied to the mIF images represented as spatial point patterns. These mathematical models, developed for landscape ecology and geographic information studies, can be applied to the TME after careful consideration of the tumor type (cold vs. hot) and the tumor immune landscape. The spatial modelling of mIF images can show observable engagement of T cells expressing immune checkpoint molecules and this can then be correlated with single-cell RNA sequencing data.

Patterns of Oncogene Coexpression at Single-Cell Resolution Influence Survival in Lymphoma

Cancers often overexpress multiple clinically relevant oncogenes, but it is not known if combinations of oncogenes in cellular subpopulations within a cancer influence clinical outcomes. Using quantitative multispectral imaging of the prognostically relevant oncogenes MYC, BCL2, and BCL6 in diffuse large B-cell lymphoma (DLBCL), we show that the percentage of cells with a unique combination MYC+BCL2+BCL6- (M+2+6-) consistently predicts survival across four independent cohorts (n = 449), an effect not observed with other combinations including M+2+6+. We show that the M+2+6- percentage can be mathematically derived from quantitative measurements of the individual oncogenes and correlates with survival in IHC (n = 316) and gene expression (n = 2,521) datasets. Comparative bulk/single-cell transcriptomic analyses of DLBCL samples and MYC/BCL2/BCL6-transformed primary B cells identify molecular features, including cyclin D2 and PI3K/AKT as candidate regulators of M+2+6- unfavorable biology. Similar analyses evaluating oncogenic combinations at single-cell resolution in other cancers may facilitate an understanding of cancer evolution and therapy resistance.

SIGNIFICANCE

Using single-cell-resolved multiplexed imaging, we show that selected subpopulations of cells expressing specific combinations of oncogenes influence clinical outcomes in lymphoma. We describe a probabilistic metric for the estimation of cellular oncogenic coexpression from IHC or bulk transcriptomes, with possible implications for prognostication and therapeutic target discovery in cancer. This article is highlighted in the In This Issue feature, p. 1027.

Antimicrobial Efficacy of Blended Essential Oil and Chlorhexidine against Periodontal Pathogen (P.gingivalis)-An In Vitro Study

Background

Essential oils (EOs) have a considerable amount of therapeutic and preventive effect in treating dental diseases due to their wider potential as antibacterial and anti-inflammatory agents. EOs like virgin coconut oil, eucalyptus oil, peppermint oil thyme oil, and clove oil, when used in combination, may further have enhanced antimicrobial effects. However, limited information exists on the synergistic effect of these oils when used in combination, especially on the primary periodontal pathogen Porphyromonas gingivalis.

Aim

The current study aims to compare the antimicrobial efficacy of commercially available EO on the periodontal pathogen, P. gingivalis, in comparison to chlorhexidine (CHX).

Materials and Methods

Antimicrobial efficacy of EO and CHX was assessed at various concentrations against the periodontal pathogen P. gingivalis, by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).

Results

P. gingivalis was seen to be sensitive at a MIC of 100 μg/ml and 50 μg/ml concentration of the EO, which is regarded as the MIC of EO against P. gingivalis and CHX effectively inhibited microbial growth at 0.4 μg/ml.

Conclusion

A combination of EOs possesses a potent antibacterial activity against P. gingivalis, and the antibacterial efficacy increases with increasing concentration of EOs.

Gibbs process distinguishes survival and reveals contact-inhibition genes in Glioblastoma multiforme

Tumor growth is a spatiotemporal birth-and-death process with loss of heterotypic contact-inhibition of locomotion (CIL) of tumor cells promoting invasion and metastasis. Therefore, representing tumor cells as two-dimensional points, we can expect the tumor tissues in histology slides to reflect realizations of spatial birth-and-death process which can be mathematically modeled to reveal molecular mechanisms of CIL, provided the mathematics models the inhibitory interactions. Gibbs process as an inhibitory point process is a natural choice since it is an equilibrium process of the spatial birth-and-death process. That is if the tumor cells maintain homotypic contact inhibition, the spatial distributions of tumor cells will result in Gibbs hard core process over long time scales. In order to verify if this is the case, we applied the Gibbs process to 411 TCGA Glioblastoma multiforme patient images. Our imaging dataset included all cases for which diagnostic slide images were available. The model revealed two groups of patients, one of which - the "Gibbs group," showed the convergence of the Gibbs process with significant survival difference. Further smoothing the discretized (and noisy) inhibition metric, for both increasing and randomized survival time, we found a significant association of the patients in the Gibbs group with increasing survival time. The mean inhibition metric also revealed the point at which the homotypic CIL establishes in tumor cells. Besides, RNAseq analysis between patients with loss of heterotypic CIL and intact homotypic CIL in the Gibbs group unveiled cell movement gene signatures and differences in Actin cytoskeleton and RhoA signaling pathways as key molecular alterations. These genes and pathways have established roles in CIL. Taken together, our integrated analysis of patient images and RNAseq data provides for the first time a mathematical basis for CIL in tumors, explains survival as well as uncovers the underlying molecular landscape for this key tumor invasion and metastatic phenomenon.

Perfectly antimagic total graphs

An one-one correspondence function λ from V (G) ∪ E (G) to the set {1, 2, …, |V (G) | + |E (G) |} is a total labeling of a finite undirected graph G without loops and multiple edges, where |V (G) |and |E (G) | are the cardinality of vertex and edge set of G respectively. A perfectly antimagic total labeling is a totally antimagic total labeling whose vertex and edge-weights that are also pairwise distint. Perfectly antimagic total (PAT) graph is a graph having such labeling. The topic of discovering perfectly antimagic total labeling of some families of graphs is discussed in this paper. We also came up with certain conclusions about dual of a perfectly antimagic total graphs. Finally, we provided that the necessary and sufficient condition for a dual of a regular and irregular PAT graph to be a PAT graph.

073 Posterior reversible encephalopathy syndrome (PRES) complicating anti-NMDA receptor encephalitis (NMDARE) with ovarian teratoma

Introduction

Anti-N-methyl-D-aspartate receptor antibody-associated encephalitis (NMDARE) is a form of autoimmune encephalitis typically affecting young women, often associated with an ovarian teratoma. Clinical features include psychiatric disturbances, seizures, dyskinesia, dysautonomia, and cardiac dys- rhythmias. Here we present a case of NMDARE complicated by posterior reversible encephalopathy syndrome (PRES). This complication has not been reported previously.

Case

A 17-year-old girl presented with acute psychosis. The neurological examination was unremark- able. MRI brain revealed left hippocampal T2 signal hyperintensity; there was a CSF lymphocytosis. NMDA-receptor antibodies in serum and CSF were detected and intravenous methylprednisolone was commenced. Progressive agitation lead to ITU admission. Plasma exchange and intravenous immuno- globulins were administered. MRI pelvis revealed a left ovarian cyst which was removed (laparoscopic salpingo-oophrectomy). Gross inspection and histopathology confirmed an ovarian teratoma. Persistently elevated blood pressure was noted for a week on ITU, associated with clinical deterioration. Rituximab was administered. A repeat MRI brain the next day revealed hyperintensities in temporo-parietal and occipital regions consistent with PRES. The second dose of rituximab was withheld. Clinical and radiologi- cal improvement was noted after a week, and the patient was discharged home.

Discussion

Encephalitis mediated dysautonomia may lead to disruption of cerebral autoregulation cul- minating in PRES. The administration of rituximab may also have contributed. This case exemplifies the uncommon complications associated with NMDARE.

dr.dvinayan@gmail.com

Cardiovascular disease risk factors and outcomes of acute myocardial infarction in young adults in two nationwide cohorts in the united states

Funding Acknowledgements

Type of funding sources: None.

Background

Acute myocardial infarction (AMI) can have considerable morbidity and devastating socioeconomic and psychological consequences in young adults. Previous studies reveal that the decline in mortality in AMI has mainly been in the older population while being comparatively less significant in younger patients. This study compares young adults (18 to 44 years) hospitalized with AMI across two nationwide cohorts, 2007 and 2017, in the United States (US). It examines the burden of AMI hospitalizations, the prevalence of comorbidities, and in-hospital outcomes in young adults a decade apart. It highlights the rise in AMI hospitalizations, lack of decrease in mortality, sex-based and racial disparities, the surge in post-MI complications, and the decline in reperfusion interventions in young AMI patients over a decade.

Purpose

Coronary heart disease prevalence is challenging to ascertain in younger adults because of limited data and frequent silent clinical presentations. AMI and its complications can cause considerable morbidity, psychological trauma, and socioeconomic burden in the young.

Methods

We identified hospitalizations for AMI in young adults in 2007 and 2017 using the weighted data from the National Inpatient Sample (NIS), which covers 20% of stratified data of all non-federal community hospitals in the US. We compared the following data between the two cohorts: admission rates, sociodemographic features, in-hospital morbidity, complications, mortality, rate of coronary interventions, and healthcare utilization between the two cohorts. We used Pearson’s Chi-square test and Mann-Whitney U test to compare categorical and continuous variables, respectively. We also applied multivariable regression analyses to assess and compare the risk of cardiovascular complications and in-hospital mortality while controlling for confounders, including age, sex, race, median household income quartile, primary insurance enrolment, and pre-existing comorbidities.

Results

AMI’s incidence was higher in males in both the cohorts, although with a decline (71.1% vs 66.1%), whereas it rose from 28.9% to 33.9% in females. Hypertension (47.8% vs 60.7%), smoking (49.7% vs 55.8%), obesity (14.8% vs 26.8%), and diabetes mellitus (22.0% vs 25.6%) increased in the 2017 cohort (Table 1). We found no significant difference in all-cause mortality (aOR = 1.01 (0.93-1.10), p=0.749). Post-AMI complications, cardiogenic shock (aOR = 1.16 (1.06-1.27), p=0.001), and fatal arrhythmias increased. Reperfusion interventions decreased in the 2017 cohort (PCI; aOR=0.95 (0.91-0.98), p<0.001; CABG; aOR=0.66 (0.61-0.71), p<0.001) (Table 2).

Conclusion

Our study highlights the rise in AMI hospitalizations, plateauing of mortality, gender disparity, the surge in post-MI complications, and a reassuring decline in the requirement of reperfusion interventions in young AMI patients over a decade.

Enhancement of the structure, solar cells and vibrational studies of undoped CuCr2O4 and La-doped CuCr2O4 semiconductor compounds

In the present paper, we report the successful synthesis of spinel-type of CuCr₂O₄ and La doped CuCr₂O₄ semiconductor nanoparticles by a microwave method. Starting with the precursor complex, this technique includes the creation of homogenous solid intermediates, which reduces atomic diffusion pathways during the microwave process. CuCr₂O₄ and La doped CuCr₂O₄ were characterized by the following analytical methods for instance X-ray diffraction (XRD), transmission electron microscopy (TEM), Ultraviolet–visible (UV–Vis) spectroscopy and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that modifying the precursor had a significant impact on the size, solar cell size, as well as reaction period of synthesizing CuCr₂O₄ and La doped CuCr₂O₄. The impacts of precursors on the morphological and structural characteristics of CuCr₂O₄ and La doped CuCr₂O₄ were examined for the first time in this publication.

Profiles of Natural and Designed Protein-Like Sequences Effectively Bridge Protein Sequence Gaps: Implications in Distant Homology Detection

Sequence-based approaches are fundamental to guide experimental investigations in obtaining structural and/or functional insights into uncharacterized protein families. Powerful profile-based sequence search methods rely on a sequence space continuum to identify non-trivial relationships through homology detection. The computational design of protein-like sequences that serve as "artificial linkers" is useful in identifying relationships between distant members of a structural fold. Such sequences act as intermediates and guide homology searches between distantly related proteins. Here, we describe an approach that represents natural intermediate sequences and designed protein-like sequences as HMM (Hidden Markov Models) profiles, to improve the sensitivity of existing search methods. Searches made within the "Profile database" were shown to recognize the parent structural fold for 90% of the search queries at query coverage better than 60%. For 1040 protein families with no available structure, fold associations were made through searches in the database of natural and designed sequence profiles. Most of the associations were made with the Alpha-alpha superhelix, Transmembrane beta-barrels, TIM barrel, and Immunoglobulin-like beta-sandwich folds. For 11 domain families of unknown functions, we provide confident fold associations using the profiles of designed sequences and a consensus from other fold recognition methods. For two DUFs (Domain families of Unknown Functions), we performed detailed functional annotation through comparisons with characterized templates of families of known function.

TP1.2.3Oncological Outcomes of Organ Preservation Strategies - Local Excision Procedures and ‘Watchful Waiting’ In Management of Low Rectal Cancers – A Systematic Review And Meta-Analysis

Objective

To evaluate local recurrence, metastases, and survival outcomes of `wait and watch’ (WW) strategy and local excision (LE) of tumours, in comparison to the present standard practice of total mesorectal excision (TME) for locally advanced rectal cancers.

Data Sources

MEDLINE, EMBASE, PubMed databases, and sources of Grey literature.

Study Selection

Randomised and non-randomised prospective studies, retrospective studies with propensity-score-matched analyses.

Data Extraction and Synthesis

These were carried out independently by two reviewers. A random-effects methodology was used for meta-analyses. Data was presented keeping with the 27-item PRISMA checklist.

Main Outcomes

The primary outcomes of interest were local recurrence, distant metastases, disease-free-survival and overall-survival, which were assessed in comparison to those associated with radical surgeries (TME).

Results

7 of the 16 studies in the systematic review were included for the quantitative synthesis and meta-analysis. Local recurrence rates were comparable amongst patients in WW group and LE group to those undergoing TME. [Risk ratio (RR) 3.07/1.41; 95% Confidence Interval (CI) 0.86-10.95/0.66-3.01; P = 0.08/P=0.89 respectively]. Rates of distant metastases in the WW group and LE group were comparable to those undergoing TME [RR = 0.71/0.94; 95% CI 0.22-2.30/0.55-1.61; P = 0.56/ P = 0.83 respectively]. The median 3-year disease-free survival among patients undergoing WW, LE procedure, and TME were 88%, 80%, and 78.2% respectively; and the median 3-year overall survival among the three groups were 96%, 93%, and 89.5% respectively.

Conclusions and Relevance

Organ-preservation strategies appear to be a viable treatment option in the management of rectal-cancers. Further research is warranted to provide stronger levels of evidence on organ-preservation strategies.

TP1.2.6Functional Outcomes of Organ Preservation Strategies - Local Excision Procedures and 'Watchful-Waiting' In Management of Low Rectal Cancers - A Systematic Review

Objective

To evaluate functional outcomes and quality of life (QOL) associated with `wait-and-watch’ (WW) strategy and local-excision (LE) of rectal tumours after neo-adjuvant therapy, in comparison to the standard practice of total-mesorectal-excision (TME) for locally-advanced-rectal-cancers.

Data Sources

Medline, EMBASE, PubMed databases, and sources of Grey literature.

Study Selection

Randomised and non-randomised prospective studies, and retrospective studies with propensity-score-matched analyses analysing outcomes of WW and LE procedures for rectal cancer.

Data Extraction and Synthesis

Risk of bias assessments and data extraction were carried out independently by two reviewers. A narrative synthesis of data was presented keeping with the 27-item PRISMA checklist.

Main Outcomes

The outcomes of interest were those of faecal-incontinence (FI), bowel and rectal-evacuatory function, sexual-function, stoma-free-survival, and quality-of-life scores, which were assessed in comparison to those associated with radical surgeries.

Results

7 studies reported functional outcomes. Faecal-incontinence, bowel, and rectal-evacuatory-function assessed by various scoring systems were found to be least affected among patients on WW strategy, followed by those undergoing local excision and most in patients undergoing TME. These reflected on the quality of life assessments (FIQOL and FACT-C questionnaires). Sexual dysfunction was not higher among patients who underwent LE compared to TME. Advantage of stoma-free-survival with organ preservation strategies was realised for up to 2 years after treatment.

Conclusions

Organ-preservation strategies appear to have a favourable functional outcome compared to the gold standard of TME for up to 2 years after the commencement of treatment. Further research is warranted to provide stronger levels of evidence regarding the same.

483 A Quality Improvement Project: Novel Electronic Operative Note Templates to Improve the Continuity of Post-Operative Patient Care

Introduction

Good Surgical Practice from RCS England encourages the use of e-health records and detailed typed operative notes. The Covid-19 pandemic has led to multi-site operating. ENT operations in our trust were split over three sites including the private sector leading to potential disruption in continuity of patient care. Physical operation notes are difficult to access in emergencies, telephonic clinics or for audit purposes. We aim to have operative notes available on patients’ e-records which adhere to RCSEng guidelines.

Method

In this QIP, we reviewed all ENT operations over a retrospective one-month period recording percentage of notes uploaded to patient e-record and the number of surgeons in theatre. We created two novel RCSEng compliant e-operative notes with a user guide, generic and tonsillectomy-specific, and prospectively collected data to complete the cycle.

Results

261 patients were included in both study periods. Only 36/134(27%) had e-operative pre-intervention improving to 71/127(56%) post-intervention. In the latter period, 76% of operations included a registrar and were more likely to have e-operative notes(72%) compared to when a consultant was operating alone(6%). There was low uptake of our tonsillectomy e-proforma(33%).

Conclusions

Our QIP has already proved effective with our templates increasing operative documentation on e-records. Increased use of e-template was more likely with the presence of a registrar in theatre. Room for improvement remains and we will re-audit after the introduction of further user-friendly operative templates and IT training. This QIP has also revealed additional operative training opportunities of which registrars can take advantage.

Where Does Interventional Radiology Fit in with Trauma Management Algorithm?

Trauma is a major cause of death in the United States, particularly in the younger population. Many traumatic deaths, as well as major morbidity, occur secondary to uncontrolled hemorrhage and eventual exsanguination. Interventional radiology plays a major role in treating these patients, and interventional techniques have evolved to the point where they are an integral part of treatment in these critically ill patients. This article reviews the role of interventional radiology in the treatment algorithms for traumatic injury sponsored by major societies and associations.

Is a single dose of preoperative antibiotic therapy effective for patients treated with megaendoprosthesis after metastatic bone tumour resection?

Purpose The timing and number of doses of antibiotics required for megaendoprosthetic replacement (MPR) in metastatic bone disease (MBD) is a matter of debate. The aim of our study is to present the results of a prospective cohort of MPR for MBD receiving a single dose of antibiotic at induction of anaesthesia.

METHODS

All patients who underwent primary MPR in MBD were included in this prospective study. All penicillin-sensitive patients received one dose of cefuroxime 1.5gm intravenous at induction. In penicillin-allergic patients, teicoplanin 1.2gm and ciprofloxacin 500 mg intravenous was administered. The patients were followed up in the wound clinic and the specialist MBD clinic at 2 weeks, 3 months, 6 months and then annually. Data collected included demographics, primary tumours, surgical procedures, complications and duration of follow-up. All calculations were performed using SPSS^® 25(IBM, USA). A p value ≤ 0.05 was considered to be significant.

RESULTS

There were 51 patients with a mean age of 65.4 years. Procedures included proximal femoral replacement (35), distal femoral replacement (7), proximal humeral replacement (4), distal humeral replacement (3) and total femoral replacement (2). Thirty-seven patients received cefuroxime, and fourteen patients received teicoplanin and ciprofloxacin at induction of anaesthesia. The deep infection rate was 1.9%. Thirty-seven patients died with a median survival of 10 months (1 to 51 months). Mean follow-up was 18.9 months (1 to 70 months).

CONCLUSION

Single dose of preoperative antibiotics at anaesthetic induction seems to be safe and effective for preoperative prophylaxis in orthopaedic oncology.

Pulmonary artery injury in left atrial appendage closure device implantation: a systematic review of a potentially fatal complication

Background

Pulmonary artery (PA) injury is a rarely reported complication following percutaneous left atrial appendage closure (LAAC). This study aims to systematically review all reported cases of PA injury associated with LAAC.

Methods

PubMed/Medline, SCOPUS, EMBASE, Google Scholar and the MAUDE databases were searched to find studies reporting PA injury during or after LAAC with the Amplatzer Amulet (AA), Amplatzer Cardiac Plug (ACP) or Watchman device through October 2019. Categorical data were reported in terms of numbers and/or percentages (%).

Results

We found 13 cases (mean age 71.4 yrs) with reported PA injury associated with LAAC. Of these, 9 were case reports, 3 were reported in observational studies, and 1 was in the MAUDE database. Most cases (n=8) were reported in Europe followed by Australia (n=2) and Asia (n=2). The indication for device implantation in all patients was a high bleeding risk with anticoagulation for atrial fibrillation. Five cases were reported with the ACP (1/5 patients died), 5 with AA (2/5 patients died), and 3 with the Watchman (1/2 patients died). Acute and late presentations following implantation were reported for all three devices. 69.2% of cases (9/13) occurred acutely (during or within 24 hours of intervention). Of these, 3/9 occurred during device implantation. 2/4 of the delayed cases occurred >2 weeks following implantation. The mortality rate for acute and delayed cases was 22% (2/9 patients) and 50% (2/4 patients), respectively. A majority of the cases were attributable to barb/strut/hook injury of the PA. PA injury was associated with a mortality rate of approximately 31%. All surviving patients were managed with surgical intervention.

Conclusion

PA injury is an infrequently reported complication following LAAC and is associated with high mortality. Cases can present acutely (intra-procedurally or within 24 hours) or delayed (>24 hours post-implantation). A majority of cases are due to direct injury of the PA by the struts/hooks/barbs of the device. Practitioners should be cognizant of this life-threatening complication, which requires a high index of suspicion for diagnosis and can occur weeks after device implantation.

Funding Acknowledgement

Type of funding source: None

Rates and causes of readmissions following index admissions for Takotsubo syndrome-a meta-analysis of 118,941 index hospitalizations

Background

Rising trends in takotsubo syndrome (TTS)-related complications warrant data to identify the rate, causes and predictors of readmission on a large scale. We conducted the first-ever meta-analysis to evaluate the pooled rate of short-term and long-term readmissions after index TTS admissions.

Methods

PubMed/Medline, EMBASE and SCOPUS databases were systematically reviewed to find studies through October 2019 reporting rates and causes of readmission following index TTS admissions. Random effects models were used to estimate pooled rates and causes of readmissions and I2 statistics were used to report inter-study heterogeneity.

Results

A total of 16 cohorts with 118,941 TTS index admissions (mean age 65–75 yrs; female >85%, median follow-up 272.5 days) revealed a 16.6% [95% CI-13.2%-20.3%, I2=99%] pooled rate of readmission. Short-term and long-term pooled readmission rates are displayed in Fig.1. The readmission rate was higher in cohorts with young patients (<70 vs. >70 yrs), smaller sample size (n<100 vs. n>100) and single-centres vs. multicentres. Studies published from the USA (16.4% vs. 14.9%) had a higher readmission rate as compared to Italy. The most frequent causes were cardiac (40.6%), respiratory (15.7%) and renal (7.0%). Among readmissions with cardiac diagnoses, heart failure was most common (40.1%).

Conclusions

This global meta-analysis revealed that the pooled rate of readmission following index TTS admissions was ∼17% and causes were mainly cardiac or respiratory.

Funding Acknowledgement

Type of funding source: None

Artificial protein sequences enable recognition of vicinal and distant protein functional relationships

High divergence in protein sequences makes the detection of distant protein relationships through homology-based approaches challenging. Grouping protein sequences into families, through similarities in either sequence or 3-D structure, facilitates in the improved recognition of protein relationships. In addition, strategically designed protein-like sequences have been shown to bridge distant structural domain families by serving as artificial linkers. In this study, we have augmented a search database of known protein domain families with such designed sequences, with the intention of providing functional clues to domain families of unknown structure. When assessed using representative query sequences from each family, we obtain a success rate of 94% in protein domain families of known structure. Further, we demonstrate that the augmented search space enabled fold recognition for 582 families with no structural information available a priori. Additionally, we were able to provide reliable functional relationships for 610 orphan families. We discuss the application of our method in predicting functional roles through select examples for DUF4922, DUF5131, and DUF5085. Our approach also detects new associations between families that were previously not known to be related, as demonstrated through new sub-groups of the RNA polymerase domain among three distinct RNA viruses. Taken together, designed sequences-augmented search databases direct the detection of meaningful relationships between distant protein families. In turn, they enable fold recognition and offer reliable pointers to potential functional sites that may be probed further through direct mutagenesis studies.

Immunological biomarkers in neuropsychiatric systemic lupus erythematosus: a comparative cross-sectional study from a tertiary care center in South India

INTRODUCTION

The prevalence of various immunological biomarkers in neuropsychiatric systemic lupus erythematosus (NPSLE) differs among various patients with varied neuropsychiatric manifestations and different populations. We studied the prevalence of these biomarkers; especially the neuron specific autoantibodies in patients with systemic lupus erythematosus (SLE) and compared them among patients with and without neuropsychiatric involvement.

METHODOLOGY

This is a comparative cross-sectional study conducted in a tertiary care hospital in South India. The prevalence of immunological biomarkers including complement levels, systemic and brain specific autoantibodies (anti-myelin antibody, anti-myelin oligodendrocyte glycoprotein and anti-myelin-associated glycoprotein antibody) were assessed and compared among those with and without NPSLE and with different NPSLE manifestations.

RESULTS

A total of 522 SLE patients were enrolled in the study. The mean age of the study participants was 28.5 ± 8.8 years and 93.5% were women. Neuropsychiatric manifestations were seen in 167 (32%) patients. Seizure was the most common neuropsychiatric manifestation seen in 41.3%, followed by psychosis (18.6%), mood disorder (16.8%), stroke (10.8%), mononeuropathy (10.2%), headache (9.6%), acute confusional state (6.6%) and aseptic meningitis (5.4%). Patients with NPSLE had a higher SLE disease activity index score. Most of the autoantibodies, that is anticardiolipin antibody (aCL), anti-β2 glycoprotein 1 antibody (β2GP1), lupus anticoagulant (LA), anti-nucleosome, anti-ribosomal P, anti-Ro52, anti-Ro60 and anti-La, were seen in higher proportion in the NPSLE group, although the difference failed to reach statistical significance. On subgroup analysis, psychosis was significantly higher in patients with anti-ribosomal P positivity than without (11.8% versus 4.1%, p.0.007; odds ratio (OR) 3.1, confidence interval (CI) 1.4-6.8), while stroke had a higher proportion among those with positive b2GP1 IgG (6.3% versus 1.8%, p.0.03; OR 3.6, CI 1.2-11.0). A higher proportion of demyelination was seen among the LA positive than the negative (10.3% versus 0.2%, p.0.03; OR 5.39, CI 1.15-24.17) and anti-myelin oligodendrocyte glycoprotein in mood disorder (14.3% versus 3.4%, p = 0.03; OR 4.66, CI 1.13-19.13).

CONCLUSION

No single biomarker correlated with NPSLE. Among different NPSLE manifestations, the prevalence of IgG β2GP1 in stroke, LA in demyelination, anti-ribosomal P in psychosis and anti-myelin oligodendrocyte glycoprotein in mood disorder were higher. Further studies on the pathogenic mechanisms underlying NPSLE and its different manifestations may help us to identify better biomarkers.

The effect of an intraorifice barrier and base under coronal restorations on the healing of apical periodontitis: a randomized controlled trial

AIM

To evaluate the effect of intraorifice barriers and bases on the healing of apical periodontitis following root canal treatment in mandibular molars.

METHODOLOGY

A total of 120 permanent mandibular molars with necrotic pulps and periapical radiolucencies (PAI score ≥ 3) were recruited. Root canal treatment was performed in all teeth using a standard protocol, following which they were randomly allocated to one of the three treatment groups: intraorifice barrier group: coronal 3-mm gutta-percha was removed and replaced with glass-ionomer cement (GIC) barrier. The floor of the pulp chamber was then sealed with 2-mm-thick GIC base followed by final composite resin restoration; base group: received 2-mm-thick GIC base before placement of composite resin restoration; and control group: had pulp chamber entirely filled with composite resin only. Follow-up was done at 3, 6, 9 and 12 months. Combination of clinical and radiographic parameters were used to assess treatment outcome. The data were analysed using Kruskal-Wallis, chi-square and Wilcoxon signed-rank tests and logistic regression analysis.

RESULTS

At the end of 12 months, the base group had the most favourable healing (97.1%), whilst the control group had the least favourable healing (83.8%). The intraorifice barrier group had healing of 92.1%. However, there was no significant difference in healing between groups at the end of the follow-up period (P > 0.05). Additional subgroup analysis revealed a nonsignificant effect of periodontal status and root filling level on periapical healing.

CONCLUSION

The use of an additional barrier under permanent restorations did not significantly improve the outcome of primary root canal treatment in posterior teeth after 12 months. However, its influence in the long term requires further evaluation.

Diagnostic utility of fluorodeoxyglucose positron emission tomography in prosthetic joint infection based on MSIS criteria

AIMS

Prosthetic joint infection (PJI) and aseptic loosening in total hip arthroplasty (THA) can present with pain and osteolysis. The Musculoskeletal Infection Society (MSIS) has provided criteria for the diagnosis of PJI. The aim of our study was to analyze the utility of F18-fluorodeoxyglucose (FDG) positron emission tomography (PET) CT scan in the preoperative diagnosis of septic loosening in THA, based on the current MSIS definition of prosthetic joint infection.

PATIENTS AND METHODS

A total of 130 painful unilateral cemented THAs with a mean follow-up of 5.17 years (sd 1.12) were included in this prospective study. The mean patient age was 67.5 years (sd 4.85). Preoperative evaluation with inflammatory markers, aspiration, and an F18 FDG PET scan were performed. Diagnostic utility tests were also performed, based on the MSIS criteria for PJI and three samples positive on culture alone.

RESULTS

The mean erythrocyte sedimentation rate, C-reactive protein, and white cell count were 47.83 mm/hr, 25.21 mg/l, and 11.05 × 10⁹/l, respectively. The sensitivity, specificity, accuracy, negative predictive value, and false-positive rate of FDG PET compared with MSIS criteria were 94.87%, 38.46 %, 56.38%, 94.59 %, and 60.21%, respectively. The false-positive rate of FDG PET compared with culture alone was 77.4%.

CONCLUSION

FDG PET has a definitive role in the preoperative evaluation of suspected PJI. This the first study to evaluate its utility based on MSIS criteria and compare it with microbiology results alone. However, FDG PET has a high false-positive rate. Therefore, we suggest that F18 FDG PET is useful in confirming the absence of infection, but if positive, may not be confirmatory of PJI. Cite this article: Bone Joint J 2019;101-B:910-914.

Combination of microwave and gamma irradiation for reduction of aflatoxin B1 and microbiological contamination in peanuts (Arachis hypogaea L.)

Aflatoxin B1 (AFB1) is a natural carcinogen commonly present in food and feed which has deleterious effects on human and animal health. Combination treatment of microwave heating and gamma irradiation has been investigated. Artificially spiked peanuts (Arachis hypogaea L.) were used with a concentration of 300 μg/kg of AFB1 to evaluate the treatment efficacy. Qualitative and quantitative analysis of AFB1 was carried out by one dimensional thin layer chromatography and enzyme-linked immune-sorbent assay (ELISA), respectively. Gamma irradiation (5, 7 and 9 kGy) alone reduced 20 to 43% of AFB1, while, only low power microwave heating (360, 480 and 600 W) reduced it by 59 to 67%. The synergistic effect of a combination treatment at 7 and 9 kGy of irradiation at any of the chosen microwave power levels and sequence of treatment was able to reduce >95% in artificially spiked peanuts. Knowing the limitation of ELISA, an Ames test was employed to determine the mutagenicity of AFB1 in combination-treated (7 kGy and 600 W) artificially spiked peanut samples, resulting in an 80-85% reduction of its mutagenicity. Quality parameters of peanuts in terms of moisture content, water activity, hardness, colour, peroxide value and free fatty acid were evaluated and observed to be retained after combination treatments. Post-treatment sensory analysis in respect of appearance, colour, texture, taste, aftertaste and overall acceptability gave satisfactory scores. The microbiological safety of treated peanuts (exclusive and combination of 7 kGy and 360-600 W) was assessed in terms of total bacterial count, aerobic spore count, and yeast and mould count. The microbiological load was completely eliminated after exclusive gamma irradiation or the combination treatments. Combination treatment (7 kGy and 600 W) demonstrated 71 to 87% reduction in AFB1 from naturally contaminated peanuts and is recommended for further commercial application.

Fold combinations in multi-domain proteins

Domain-domain interactions in multi-domain proteins play an important role in the combined function of individual domains for the overall biological activity of the protein. The functions of the tethered domains are often coupled and hence, limited numbers of domain architectures with defined folds are known in nature. Therefore, it is of interest to document the available fold-fold combinations and their preference in multi-domain proteins. Hence, we analyzed all multi-domain proteins with known structures in the protein databank and observed that only about 860 fold-fold combinations are present among them. Analyses of multi-domain proteins represented in sequence database result in recognition of 29,860 fold-fold combinations and it accounts for only 2.8% of the theoretically possible 1,036,080 (1439C2) fold-fold combinations. The observed preference for fold-fold combinations in multi-domain proteins is interesting in the context of multiple functions through structural adaptation by gene fusion.

Targeting the paracrine hormone-dependent guanylate cyclase/cGMP/phosphodiesterases signaling pathway for colorectal cancer prevention

Colorectal cancer (CRC) is one of the leading causes of cancer related-deaths. The risk of development of CRC is complex and multifactorial, and includes disruption of homeostasis of the intestinal epithelial layer mediated though dysregulations of tumor suppressing/promoting signaling pathways. Guanylate cyclase 2C (GUCY2C), a membrane-bound guanylate cyclase receptor, is present in the apical membranes of intestinal epithelial cells and maintains homeostasis. GUCY2C is activated upon binding of paracrine hormones (guanylin and uroguanylin) that lead to formation of cyclic GMP from GTP and activation of downstream signaling pathways that are associated with normal homeostasis. Dysregulation/suppression of the GUCY2C-mediated signaling promotes CRC tumorigenesis. High-calorie diet-induced obesity is associated with deficiency of guanylin expression and silencing of GUCY2C-signaling in colon epithelial cells, leading to tumorigenesis. Thus, GUCY2C agonists, such as linaclotide, exhibit considerable role in preventing CRC tumorigenesis. However, phosphodiesterases (PDEs) are elevated in intestinal epithelial cells during CRC tumorigenesis and block GUCY2C-mediated signaling by degrading cyclic GMP to 5`-GMP. PDE5-specific inhibitors, such as sildenafil, show considerable anti-tumorigenic potential against CRC by amplifying the GUCY2C/cGMP signaling pathway, but cannot achieve complete anti-tumorigenic effects. Hence, dual targeting the elevation of cGMP by providing paracrine hormone stimuli to GUCY2C and by inhibition of PDEs may be a better strategy for CRC prevention than alone. This review delineates the involvement of the GUCY2C/cGMP/PDEs signaling pathway in the homeostasis of intestinal epithelial cells. Further, the events are associated with dysregulation of this pathway during CRC tumorigenesis are also discussed. In addition, current updates on targeting the GUCY2C/cGMP/PDEs pathway with GUCY2C agonists and PDEs inhibitors for CRC prevention and treatment are described in detail.