COVID-19 in non-hospitalised adults caused by either SARS-CoV-2 sub-variants Omicron BA.1, BA.2, BA.4/5 or Delta associates with similar illness duration, symptom severity and viral kinetics, irrespective of vaccination history

BACKGROUND

SARS-CoV-2 variant Omicron rapidly evolved over 2022, causing three waves of infection due to sub-variants BA.1, BA.2 and BA.4/5. We sought to characterise symptoms and viral loads over the course of COVID-19 infection with these sub-variants in otherwise-healthy, vaccinated, non-hospitalised adults, and compared data to infections with the preceding Delta variant of concern (VOC).

METHODS

In a prospective, observational cohort study, healthy vaccinated UK adults who reported a positive polymerase chain reaction (PCR) or lateral flow test, self-swabbed on alternate weekdays until day 10. We compared participant-reported symptoms and viral load trajectories between infections caused by VOCs Delta and Omicron (sub-variants BA.1, BA.2 or BA.4/5), and tested for relationships between vaccine dose, symptoms and PCR cycle threshold (Ct) as a proxy for viral load using Chi-squared (χ2) and Wilcoxon tests.

RESULTS

563 infection episodes were reported among 491 participants. Across infection episodes, there was little variation in symptom burden (4 [IQR 3-5] symptoms) and duration (8 [IQR 6-11] days). Whilst symptom profiles differed among infections caused by Delta compared to Omicron sub-variants, symptom profiles were similar between Omicron sub-variants. Anosmia was reported more frequently in Delta infections after 2 doses compared with Omicron sub-variant infections after 3 doses, for example: 42% (25/60) of participants with Delta infection compared to 9% (6/67) with Omicron BA.4/5 (χ2 P < 0.001; OR 7.3 [95% CI 2.7-19.4]). Fever was less common with Delta (20/60 participants; 33%) than Omicron BA.4/5 (39/67; 58%; χ2 P = 0.008; OR 0.4 [CI 0.2-0.7]). Amongst infections with an Omicron sub-variants, symptoms of coryza, fatigue, cough and myalgia predominated. Viral load trajectories and peaks did not differ between Delta, and Omicron, irrespective of symptom severity (including asymptomatic participants), VOC or vaccination status. PCR Ct values were negatively associated with time since vaccination in participants infected with BA.1 (β = -0.05 (CI -0.10-0.01); P = 0.031); however, this trend was not observed in BA.2 or BA.4/5 infections.

CONCLUSION

Our study emphasises both the changing symptom profile of COVID-19 infections in the Omicron era, and ongoing transmission risk of Omicron sub-variants in vaccinated adults.

TRIAL REGISTRATION

NCT04750356.

The association between bronchopulmonary dysplasia grade and risks of adverse neurodevelopmental outcomes among preterm infants born at less than 30 weeks of gestation

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a multifactorial disease with neurodevelopmental implications. This study aims to quantify the risks of adverse neurodevelopmental outcomes for each BPD grade among preterm infants born at less than 30 weeks' gestation.

METHODS

We retrospectively studied infants who received care in our institution until at least 36 weeks postmenstrual age and had a formal neurodevelopmental assessment in our infant follow-up clinic using the Bayley Scales for Infant and Toddler Development (BSID). We assessed the association between BPD grade and adverse neurodevelopmental outcomes using descriptive statistics and regression models.

RESULTS

Two hundred and fifty infants, including 89 (35.6%), 87 (34.8%), 65 (20.6%), and 9 (3.6%) with No BPD, Grade 1, Grade 2, and Grade 3 BPD, were included in the study. Small for gestational age, late pulmonary hypertension, dexamethasone administration, and adverse neurodevelopmental outcomes were more common as BPD grade increased. In a logistic regression analysis, Grades 2 and 3, but not Grade 1, BPD were associated with increased odds of a composite adverse neurodevelopmental outcome by 2.7 and 7.2 folds, respectively. A BSID domain-specific analysis showed that higher grades were associated with lower scores in the cognitive, gross motor, and fine motor domains.

CONCLUSIONS

Grades 2 and 3 BPD, but not Grade 1, correlate with risks of adverse neurodevelopmental outcomes at a grade-dependent manner in our single-center cohort retrospective study. Further validation using a multi-center large cohort is warranted.

Preoperative radiographs to predict component malposition in direct anterior approach total hip arthroplasty

INTRODUCTION

There is conflicting evidence as to whether or not patients undergoing total hip arthroplasty (THA) via the direct anterior approach (DAA) have increased risk of component malposition. The aim of this study was to investigate whether specific preoperative radiographic features were predictive of postoperative component malposition in DAA THA.

PATIENTS AND METHODS

We examined 204 THA operations performed for osteoarthritis via the DAA at a single institution. Preoperative radiographs were analysed with numerous pre-specified measurements and classifications being recorded. Postoperative radiographs were analysed to determine if any of these preoperative radiographic factors correlated with component malposition in regard to cup inclination, cup version, femoral stem coronal alignment, leg-length discrepancy (LLD) and femoral offset discrepancy.

RESULTS

Numerous preoperative factors were associated with component malposition. Coxa profunda was found to be a significant predictor of cup anteversion being outside of the target range (p = 0.0089) and an increased centre-edge angle was a significant predictor for a postoperative LLD (p = 0.0134). A decreased neck-shaft angle (p = 0.0007) and a lower preoperative LLD (p = 0.0019) were both predictive of femoral stem coronal malalignment.

CONCLUSIONS

Preoperative radiographs can be a valuable tool for surgeons in predicting patients at risk of component malposition in DAA THA.

P062 COVID-19 hyperinflammation can be predicted using routine clinical laboratory markers

Background/Aims

Since early in the COVID-19 pandemic, there has been interest in the concept that some morbidity and mortality may be due to excessive inflammation. Several definitions of COVID-19 hyperinflammation (COV-HI) have been proposed, including Manson criteria (C-reactive protein, CRP ≥150mg/L or doubling above 50mg/L in 24 hours and/or ferritin 1500ug/L); and Webb criteria (includes CRP ≥150mg/L or ferritin ≥750ug/L). A consistent finding has been worse outcomes. Little is known regarding the underlying pathologies separating these patients from others.

Aim

To investigate whether machine learning using standard laboratory features can identify a distinguishing ‘COV-HI signature’.

Methods

A database of daily clinical and laboratory features was collected from 611 patients admitted to hospital with confirmed COVID-19 during the first wave of community-acquired infection at University College London Hospitals, Sheffield Teaching Hospitals, Newcastle upon Tyne Hospitals and Royal Wolverhampton. All data prior to mechanical ventilation were interrogated. Patients were categorised as COV-HI based on Webb thresholds (CRP &gt;150 mg/L or ferritin ≥750ug/L). Laboratory features (peak or nadir depending on recognised predictors of illness severity) included: minimum lymphocyte count 10^9/L; minimum monocyte count 10^9/L; minimum haemoglobin g/dL, minimum albumin g/L; maximum neutrophils count 10^9/L; maximum alanine aminotransferase IU/L; maximum platelet count 10^9/L and maximum creatinine μmol/L. The data were analysed using unsupervised clustering and supervised machine learning models (logistic regression, support vector machine, decision trees, random forest classification (RF), naïve bayes and k-nearest neighbours) using Orange 3.29.1 software.

Results

463 patients had sufficient data to determine Cov-HI status: 361 met COV-Hi definition at any point pre- ventilation during admission (median age 71, 65.93% male), 102 patients did not (median age 73, 51% male). In keeping with our previous work, COV-HI was associated with increased mortality (p &lt; 0.0001), Odds ratio 3.506 (CI 1.871-6.916), relative risk 2.708 (CI 1.600-4.734). Multiple logistic regression revealed no significant relationship between sex and mortality (p 0.6673, Male Odds ratio 0.90). Unsupervised hierarchical clustering using laboratory features identified two clusters: Cluster-1, comprising 72.8% patients without hyperinflammation; and Cluster-2, comprising 73.3% COV-HI. Supervised machine learning models were tested using the same features. All models predicted COV-HI with good accuracy; the RF model performed best (area under the curve 0.818, classification accuracy 0.803, F1 0.79, Precision 0.85, Recall 0.74) and identified maximum neutrophil count and minimum albumin level as the most important features contributing to the classification.

Conclusion

Patients with hyperinflammation defined by CRP and ferritin thresholds share other global derangements in laboratory markers, suggesting shared pathology. Outcomes are less good in this patient group. The importance of neutrophils to the models is consistent with an association with COVID-19 disease severity and the possible contribution of neutrophil extracellular traps to pathology, while albumin is a known marker of inflammation.

Disclosure

M. Hutchinson: None. R. Tattersall: None. E.C. Jury: None. E. Hawkins: None. J. Manson: None.

Differences in obstetrical care and outcomes associated with the proportion of the obstetrician's shift completed

BACKGROUND

Understanding and improving obstetrical quality and safety is an important goal of professional societies, and many interventions such as checklists, safety bundles, educational interventions, or other culture changes have been implemented to improve the quality of care provided to obstetrical patients. Although many factors contribute to delivery decisions, a reduced workload has addressed how provider issues such as fatigue or behaviors surrounding impending shift changes may influence the delivery mode and outcomes.

OBJECTIVE

The objective was to assess whether intrapartum obstetrical interventions and adverse outcomes differ based on the temporal proximity of the delivery to the attending's shift change.

STUDY DESIGN

This was a secondary analysis from a multicenter obstetrical cohort in which all patients with cephalic, singleton gestations who attempted vaginal birth were eligible for inclusion. The primary exposure used to quantify the relationship between the proximity of the provider to their shift change and a delivery intervention was the ratio of time from the most recent attending shift change to vaginal delivery or decision for cesarean delivery to the total length of the shift. Ratios were used to represent the proportion of time completed in the shift by normalizing for varying shift lengths. A sensitivity analysis restricted to patients who were delivered by physicians working 12-hour shifts was performed. Outcomes chosen included cesarean delivery, episiotomy, third- or fourth-degree perineal laceration, 5-minute Apgar score of <4, and neonatal intensive care unit admission. Chi-squared tests were used to evaluate outcomes based on the proportion of the attending's shift completed. Adjusted and unadjusted logistic models fitting a cubic spline (when indicated) were used to determine whether the frequency of outcomes throughout the shift occurred in a statistically significant, nonlinear pattern RESULTS: Of the 82,851 patients eligible for inclusion, 47,262 (57%) had ratio data available and constituted the analyzable sample. Deliveries were evenly distributed throughout shifts, with 50.6% taking place in the first half of shifts. There were no statistically significant differences in the frequency of cesarean delivery, episiotomy, third- or fourth-degree perineal lacerations, or 5-minute Apgar scores of <4 based on the proportion of the shift completed. The findings were unchanged when evaluated with a cubic spline in unadjusted and adjusted logistic models. Sensitivity analyses performed on the 22.2% of patients who were delivered by a physician completing a 12-hour shift showed similar findings. There was a small increase in the frequency of neonatal intensive care unit admissions with a greater proportion of the shift completed (adjusted P=.009), but the findings did not persist in the sensitivity analysis.

CONCLUSION

Clinically significant differences in obstetrical interventions and outcomes do not seem to exist based on the temporal proximity to the attending physician's shift change. Future work should attempt to directly study unit culture and provider fatigue to further investigate opportunities to improve obstetrical quality of care, and additional studies are needed to corroborate these findings in community settings.

Response to "isolated head tremor: A DAT SPECT and somatosensory temporal discrimination study."

In response to Ferrazano and colleagues' observation of normal DAT binding in patients with isolated head tremor but with abnormal STDT, we report normal 123-IBZM SPECT in a cohort of patients with adult-onset idiopathic focal dystonia with cervical dystonia and their unaffected first-degree relatives both with normal and abnormal TDTs. We discuss molecular imaging findings in dystonia.

OP0269 A COMBINED CLINICAL AND BIOMARKER ALGORITHM TO PREDICT FVC DECLINE IN SYSTEMIC SCLEROSIS ASSOCIATED INTERSTITIAL LUNG DISEASE: RESULTS FROM AN INTERNATIONAL MULTICENTRE OBSERVATIONAL COHORT

Background:

Interstitial lung disease (ILD) is the leading cause of mortality in patients with Systemic Sclerosis (SSc). Forced Vital Capacity (FVC) is a major indicator of severity in SSc ILD. The ELF serum test and its constituent biomarkers (HA, PIIINP and TIMP-1) have shown to correlate with FVC in two large, independent multicentre cohorts of 457 patients, but also showed a correlation with age.

Objectives:

Here we aimed to investigate the relationship of the ELF biomarkers and age in a large population of healthy controls and to identify a combined clinical and biomarkers model to stratify for risk of ILD progression in a multicentre longitudinal cohort of patients with SSc.

Methods:

ELF score was measured in sera from 925 healthy controls in one centre and 869 longitudinal samples from 254 SSc patients from 6 centres across 4 European countries. Clinical data were recorded according to EUSTAR Minimal Essential dataset. FVC% change over time was estimated by Mixed-effects modelling. Patients were then divided in two groups: progressors, with a %FVC drop > 3%/year (according to published MCID) and a group of patients with stable or improving FVC. Lasso penalised regression was carried out with biomarkers and the available clinical and demographic variables at patient’s first visit as potential predictors. The resulting linear predictor was used to derive two thresholds, one for optimal sensitivity (rule-out) and one for optimal specificity (rule-in). Patients within thresholds were further selected according to the ratio of TIMP-1: PIIINP (Figure 1).

Results:

HA was the only ELF biomarker that correlated significantly with age in the healthy control cohort. Therefore, we defined by linear regression a “residual HA” which accounted for age. TIMP1, PIIINP and residual HA were then considered as distinct biomarkers in the analysis of the SSc cohort. 189 SSc patients with 785 time-points had complete datasets and were included in the analysis. Median follow up was 33 months (IQR 18-48). One-hundred and forty patients (74%) were classified as non progressors, 94 (50%) with no change or improving FVC and 46 (24%) with FVC drop <3% year. 49 patients (26%) were classed as progressors (drop of 3%/year or more in FVC, median slope -4.7%/year). Variable selection via Lasso penalised logistic regression resulted in a model with a c-index of 0.69 (95% CI: 0.60-0.78)) and contained age, disease duration (from first non-Raynaud’s symptom), residual HA, anti-centromere antibodies (ACA) status, previous diagnosis of ILD, joint synovitis and history of protein pump inhibitor use. A two-step process was developed using the linear predictor from the model and the ratio of TIMP-1 and PIIINP (Figure 1). The stratification tool increased by nearly two-fold the ability to predict progressors in any 12 months interval (46 to 49% predictive value vs 26% probability) identifying an 82 to 91% negative predictive value for progression.

Conclusion:

Building on the face and content validity of the biomarkers included in the ELF score, here we identify an easy to assess combined clinical and biomarker model to stratify patients for their risk of ILD progression. Despite its derivation from a large multicentre cohort, independent validation will determine the clinical value of Scleroscore as a stratification tool for risk of progression of SSc ILD.

Disclosure of Interests:

Michelle Hutchinson: None declared, Giuseppina Abignano: None declared, Jelena Blagojevic: None declared, Silvia Laura Bosello: None declared, Yannick Allanore Grant/research support from: Alpine, Boehringer Ingelheim, Genentech/Roche, Medsenic, and Sanofi, Christopher Denton Consultant of: Corbus, Actelion, GlaxoSmithKline, Bayer, Sanofi, Galapagos, Inventiva, Boehringer Ingelheim, Roche, CSL Behring, Acceleron, Horizon, Arxx Therapeutics, Grant/research support from: Corbus, Actelion, GlaxoSmithKline, Bayer, Sanofi, Galapagos, Inventiva, Boehringer Ingelheim, Roche, CSL Behring, Acceleron, Horizon, Arxx Therapeutics, Oliver Distler Consultant of: Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, ChemomAb, Corbus Pharmaceuticals, CSL Behring, Galapagos NV, Glenmark Pharmaceuticals, GSK, Horizon (Curzion) Pharmaceuticals, Inventiva, iQvia, Italfarmaco, iQone, Kymera Therapeutics, Lilly, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Serodapharm, Topadur, Target Bioscience and UCB, Grant/research support from: Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, ChemomAb, Corbus Pharmaceuticals, CSL Behring, Galapagos NV, Glenmark Pharmaceuticals, GSK, Horizon (Curzion) Pharmaceuticals, Inventiva, iQvia, Italfarmaco, iQone, Kymera Therapeutics, Lilly, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Serodapharm, Topadur, Target Bioscience and UCB, Paul Emery Consultant of: Lilly, Abbvie, Roche, Grant/research support from: Lilly, Marco Matucci-Cerinic Consultant of: Chemomab, Lilly, Abbvie, Actelion, Francesco Del Galdo Speakers bureau: Astra-Zeneca, Boehringer Ingelheim, Actelion, Consultant of: Astra-Zeneca, Mitsubishi-Tanabe, Capella Biosciences, Chemomab, Actelion, Boehringer-Ingelheim, Grant/research support from: Capella Biosciences, Chemomab, Kymab, Mitsubishi-Tanabe

P130 The relationship between antinuclear antibodies and erosive disease in patients with rheumatoid arthritis

Background/Aims 

The effects of antinuclear antibodies (ANA) in rheumatoid arthritis (RA) are not fully characterised. Studies investigating the effect of ANA on disease activity in RA have yielded mixed results. The presence of ANA has been correlated with higher levels of CRP and joint inflammation in RA. Evidence suggests that ANA positivity at baseline may predict poor response to both traditional disease modifying agents and biologic therapy. ANA may also be associated with higher incidences of ocular disease, Felty’s syndrome, vasculitis and subjective pain in RA patients. On the other hand, other studies showed a lack of correlation between ANA status and joint inflammation in RA. Our study investigates the relationship between ANA positivity and joint erosions in rheumatoid patients.

Methods 

This is a cross-sectional study of patients attending the early arthritis clinic at Northwick Park Hospital in London over a five year period (2014-2019). A total of 631 patients were identified of whom 261 had RA. We collected data on the age, gender, ANA positivity, the presence of anti-CCP (anti cyclic-citrullinated peptide) antibodies and rheumatoid factor (RF) at presentation as well as the presence of erosive disease on radiological reports of hand X-rays. Positive ANA was defined as having a titre of 1:80 or greater. Patients with missing ANA result or hand X-ray reports were excluded, leaving 228 patients. Two-tailed Chi-square tests for categorical data and two-tailed student’s t-tests for continuous data were performed to determine the statistical significance of comparisons made between the ANA positive and negative groups.

Results 

Of the 228 patients, 49 (21.5%) were male and 179 (78.5%) were female. The mean age was 58 years. 84 (36.8%) patients were ANA positive (group 1) and 144 (63.2%) were ANA negative (group 2). In group 1, 23/84 (27.4%) patients had erosive disease. In group 2, erosions were found in 25/144 patients (17.4%). This difference was not statistically significant (p = 0.073). The number of patients who were RF positive in groups 1 and 2 were 79.5% and 73.6% respectively (p = 0.317); 75/84 (89.3%) patients in group 1 and 113/143 (79.0%) in group 2 were anti-CCP antibody positive (p = 0.048). The means of the age of patients were 53 and 62 years in group 1 and group 2 respectively (p &lt; 0.0001); the ANA positive group was significantly younger. The male:female ratio was 13:71 in group 1 and 36:108 in group 2 (p = 0.091).

Conclusion 

Our study showed no significant association between ANA status and erosive disease in RA, although a greater proportion of patients had erosions in the ANA positive group. Larger observational studies may better study this relationship.

Disclosure 

T. Guruparan: None. M. Hutchinson: None. R. Hayward: None. H. Penn: None. P. Kalia: None.

Macrophages Mediate the Antitumor Effects of the Oncolytic Virus HSV1716 in Mammary Tumors

Oncolytic viruses (OV) have been shown to activate the antitumor functions of specific immune cells like T cells. Here, we show OV can also reprogram tumor-associated macrophage (TAM) to a less immunosuppressive phenotype. Syngeneic, immunocompetent mouse models of primary breast cancer were established using PyMT-TS1, 4T1, and E0771 cell lines, and a metastatic model of breast cancer was established using the 4T1 cell line. Tumor growth and overall survival was assessed following intravenous administration of the OV, HSV1716 (a modified herpes simplex virus). Infiltration and function of various immune effector cells was assessed by NanoString, flow cytometry of dispersed tumors, and immunofluorescence analysis of tumor sections. HSV1716 administration led to marked tumor shrinkage in primary mammary tumors and a decrease in metastases. This was associated with a significant increase in the recruitment/activation of cytotoxic T cells, a reduction in the presence of regulatory T cells and the reprograming of TAMs towards a pro-inflammatory, less immunosuppressive phenotype. These findings were supported by in vitro data demonstrating that human monocyte-derived macrophages host HSV1716 replication, and that this led to immunogenic macrophage lysis. These events were dependent on macrophage expression of proliferating cell nuclear antigen (PCNA). Finally, the antitumor effect of OV was markedly diminished when TAMs were depleted using clodronate liposomes. Together, our results show that TAMs play an essential role in support of the tumoricidal effect of the OV, HSV1716-they both host viral replication via a novel, PCNA-dependent mechanism and are reprogramed to express a less immunosuppressive phenotype.

Modifying nutritional substrates induces macrovesicular lipid droplet accumulation and metabolic alterations in a cellular model of hepatic steatosis

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) begins with steatosis, where a mixed macrovesicular pattern of large and small lipid droplets (LDs) develops. Since in vitro models recapitulating this are limited, the aims of this study were to develop mixed macrovesicular steatosis in immortalized hepatocytes and investigate effects on intracellular metabolism by altering nutritional substrates.

METHODS

Huh7 cells were cultured in 11 mM glucose and 2% human serum (HS) for 7 days before additional sugars and fatty acids (FAs), either with 200 µM FAs (low fat low sugar; LFLS), 5.5 mM fructose + 200 µM FAs (low fat high sugar; LFHS), or 5.5 mM fructose + 800 µM FAs (high fat high sugar; HFHS), were added for 7 days. FA metabolism, lipid droplet characteristics, and transcriptomic signatures were investigated.

RESULTS

Between the LFLS and LFHS conditions, there were few notable differences. In the HFHS condition, intracellular triacylglycerol (TAG) was increased and the LD pattern and distribution was similar to that found in primary steatotic hepatocytes. HFHS-treated cells had lower levels of de novo-derived FAs and secreted larger, TAG-rich lipoprotein particles. RNA sequencing and gene set enrichment analysis showed changes in several pathways including those involved in metabolism and cell cycle.

CONCLUSIONS

Repeated doses of HFHS treatment resulted in a cellular model of NAFLD with a mixed macrovesicular LD pattern and metabolic dysfunction. Since these nutrients have been implicated in the development of NAFLD in humans, the model provides a good physiological basis for studying NAFLD development or regression in vitro.

Intrahepatic Fat and Postprandial Glycemia Increase After Consumption of a Diet Enriched in Saturated Fat Compared With Free Sugars

OBJECTIVE

Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.

RESEARCH DESIGN AND METHODS

Sixteen overweight males were randomized to consume the SFA or SUGAR diet for 4 weeks before consuming the alternate diet after a 7-week washout period. The metabolic effects of the respective diets on IHTAG content, hepatic DNL, and whole-body metabolism were investigated using imaging techniques and metabolic substrates labeled with stable-isotope tracers.

RESULTS

Consumption of the SFA diet significantly increased IHTAG by mean ± SEM 39.0 ± 10.0%, while after the SUGAR diet IHTAG was virtually unchanged. Consumption of the SFA diet induced an exaggerated postprandial glucose and insulin response to a standardized test meal compared with SUGAR. Although whole-body fat oxidation, lipolysis, and DNL were similar following the two diets, consumption of the SUGAR diet resulted in significant (P < 0.05) decreases in plasma total, HDL, and non-HDL cholesterol and fasting β-hydroxybutyrate plasma concentrations.

CONCLUSIONS

Consumption of an SFA diet had a potent effect, increasing IHTAG together with exaggerating postprandial glycemia. The SUGAR diet did not influence IHTAG and induced minor metabolic changes. Our findings indicate that a diet enriched in SFA is more harmful to metabolic health than a diet enriched in free sugars.

A new staging system for cardiac transthyretin amyloidosis

Aims

Cardiac transthyretin (ATTR) amyloidosis is an increasingly recognized, progressive, and fatal cardiomyopathy, the natural history of which remains unclear. We sought to establish and validate a new prognostic staging system applicable to patients with both wild-type ATTR (ATTRwt) and hereditary variant ATTR (ATTRv) amyloid cardiomyopathy.

Methods and results

Eight hundred and sixty-nine patients with cardiac ATTR amyloidosis (553 with ATTRwt and 316 with ATTRv) attending the UK National Amyloidosis Centre were stratified into three disease stages at baseline on the basis of cut points in two universally measured biomarkers, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and estimated glomerular filtration rate (eGFR). Stage I was defined as NT-proBNP ≤3000 ng/L and eGFR ≥45 ml/min, Stage III was defined as NT-proBNP >3000 ng/L and eGFR <45 ml/min, and the remainder were Stage II. The staging system was validated in a cohort of 318 patients with cardiac ATTR amyloidosis from France. Median survival among 393 (45%) Stage I patients was 69.2 months, 334 (38%) Stage II patients was 46.7 months, and 142 (16%) Stage III patients was 24.1 months (P < 0.0001). After adjusting for age, compared with Stage I, the hazard ratio (HR) for death for Stage II was 2.05 [confidence interval (CI) 1.54-2.72, P < 0.001] and for Stage III was 3.80 (CI 2.73-5.28, P < 0.001). HRs and statistical significance were little altered by transthyretin genotype and were maintained in the validation cohort.

Conclusion

This simple, universally applicable staging system stratifies patients with both ATTRwt and ATTRv amyloid cardiomyopathy into prognostic categories. It will be of value in the design of forthcoming clinical trials of novel amyloid-specific therapies.

Haemophagocytic lymphohisticytosis-an underrecognized hyperinflammatory syndrome

Haemophagocytic lymphohisticytosis (HLH) is a syndrome of uncontrolled, severe systemic inflammation (hyperinflammation) arising either from a genetic immune system defect [primary (pHLH)] or triggered as a complication of malignancy, infection, or rheumatologic disease [secondary (sHLH)]. Patients with HLH often have non-specific symptoms and become progressively and critically unwell, with fever, cytopenia and multi-organ failure. Untreated, HLH is almost universally fatal, but even when treated, mortality is high, particularly when HLH complicates malignancy. HLH is managed with immunosuppression, and this can seem difficult to justify in such unwell patients. This review aims to examine the diagnostic and treatment challenges posed by sHLH and to improve recognition among rheumatologists who, being expert in the management of multisystem diseases and in the use of immunosuppression, are ideally placed to deliver care and build an evidence base for better disease characterization and treatment.

How to implant a phrenic nerve stimulator for treatment of central sleep apnea?

Background

Central sleep apnea (CSA) is a breathing disorder caused by the intermittent absence of central respiratory drive. Transvenous phrenic nerve stimulation is a new therapeutic option, recently approved by the FDA , for the treatment of CSA.

Objective

To describe the technique used to implant the transvenous phrenic nerve stimulation system (the remedē System, Respicardia, Inc).

Methods

The remedē System is placed in the pectoral region, typically on the right side. A single stimulation lead is placed in either the left pericardiophrenic vein (PPV) or the right brachiocephalic vein (RBC). A sensing lead is placed into the azygous vein to detect respiration.

Results

In the remedē System Pivotal trial, 147 of 151 (97%) patients were successfully implanted with the system. Sixty‐two percent of stimulation leads were placed in the PPV and 35% in the RBC. Mean procedure time was 2.7 ± 0.8 hours and 94% of patients were free from implant‐related serious adverse events through 6 months.

Conclusion

In patients with CSA, transvenous phrenic nerve stimulation is an effective and safe therapy with an implant procedure similar to that of cardiac implantable electronic devices.

A combined tension-band braided polyester and suture button technique is a valuable treatment alternative for transverse patellar fractures in athletes

PURPOSE

Transverse patellar fractures (TPFs) are uncommon in athletes, and their treatment can be challenging. Stable fixation is commonly achieved by compression screw fixation and stainless steel cerclage wire, but this technique can be associated with complications like nonunion, infection and the need for early hardware removal. We used a combined tension-band (figure-of-eight) braided polyester and suture button technique to treat four athletes who presented with transverse patellar fractures. This technique has shown to be a valuable alternative to the classic technique and allows for adequate fracture compression, stability and union in TPF.

METHODS

Using a tension-band braided polyester and suture button technique (Arthrex FibreTape^R&TightRope^R), we treated four athletes with transverse patellar fractures from September 2015 till January 2017. The polyester was looped over the four suture button fixation points and tensioned in a figure-of-eight fashion. The average age of the athletes was 26 years (range 17-36). Follow-up ranged from 5 to 21 months. All four patients were treated using the same surgical technique (minimally invasive surgery) with the same postoperative recovery and the same physiotherapy protocol.

RESULTS

Full recovery using suture button adjustable loop fixation device was obtained in all four cases within 3 months after surgery, with fracture healing confirmed on postoperative radiographs. No patients required hardware removal. Potential problems with this technique can include bony tunnel malpositioning or soft tissue interpositioning underneath the suture buttons.

CONCLUSION

The combination of a suture button fixation and a braided polyester tension-band technique has shown to be a valuable alternative to the fracture management of transverse patella fractures in athletes. This results in fracture healing, low risk of complications and no need for hardware removal.

Neonatal outcomes of elective early-term births after demonstrated fetal lung maturity

BACKGROUND

Studies of early-term birth after demonstrated fetal lung maturity show that respiratory and other outcomes are worse with early-term birth (37⁰-38⁶ weeks) even after demonstrated fetal lung maturity when compared with full-term birth (39⁰-40⁶ weeks). However, these studies included medically indicated births and are therefore potentially limited by confounding by the indication for delivery. Thus, the increase in adverse outcomes might be due to the indication for early-term birth rather than the early-term birth itself.

OBJECTIVE

We examined the prevalence and risks of adverse neonatal outcomes associated with early-term birth after confirmed fetal lung maturity as compared with full-term birth in the absence of indications for early delivery.

STUDY DESIGN

This is a secondary analysis of an observational study of births to 115,502 women in 25 hospitals in the United States from 2008 through 2011. Singleton nonanomalous births at 37-40 weeks with no identifiable indication for delivery were included; early-term births after positive fetal lung maturity testing were compared with full-term births. The primary outcome was a composite of death, ventilator for ≥2 days, continuous positive airway pressure, proven sepsis, pneumonia or meningitis, treated hypoglycemia, hyperbilirubinemia (phototherapy), and 5-minute Apgar <7. Logistic regression and propensity score matching (both 1:1 and 1:2) were used.

RESULTS

In all, 48,137 births met inclusion criteria; the prevalence of fetal lung maturity testing in the absence of medical or obstetric indications for early delivery was 0.52% (n = 249). There were 180 (0.37%) early-term births after confirmed pulmonary maturity and 47,957 full-term births. Women in the former group were more likely to be non-Hispanic white, smoke, have received antenatal steroids, have induction, and have a cesarean. Risks of the composite (16.1% vs 5.4%; adjusted odds ratio, 3.2; 95% confidence interval, 2.1-4.8 from logistic regression) were more frequent with elective early-term birth. Propensity scores matching confirmed the increased primary composite in elective early-term births: adjusted odds ratios, 4.3 (95% confidence interval, 1.8-10.5) for 1:1 and 3.5 (95% confidence interval, 1.8-6.5) for 1:2 matching. Among components of the primary outcome, CPAP use and hyperbilirubinemia requiring phototherapy were significantly increased. Transient tachypnea of the newborn, neonatal intensive care unit admission, and prolonged neonatal intensive care unit stay (>2 days) were also increased with early-term birth.

CONCLUSION

Even with confirmed pulmonary maturity, early-term birth in the absence of medical or obstetric indications is associated with worse neonatal respiratory and hepatic outcomes compared with full-term birth, suggesting relative immaturity of these organ systems in early-term births.

Cognitive dysfunction in early multiple sclerosis: a review

Cognitive impairment is a common and disabling feature of Multiple Sclerosis (MS), including early MS, and may even pre-date any physical symptoms. It contributes even more to withdrawal from work than physical disability. Here, we provide an overview of cognitive impairment in MS, particularly in early MS where it is most commonly under-reported and under-treated. We address the presenting features of CI, its impact on quality of life, and its validated assessments (in particular the use of Brief International Cognitive Assessment in MS for use in a clinical setting). We review the insights radiology has given us into the pathogenesis of cognitive impairment in MS, particularly in early CI and in cognitively preserved MS patients. We review current treatments for cognitive impairment, primarily cognitive rehabilitation. We address the evidence for its associated co-morbidities, which may exacerbate or trigger CI, and should therefore be addressed early in the disease course (smoking, alcohol, mood, fatigue and potential co-existing sleep disorders, exercise, and vitamin D). The article supports the importance for early recognition and management of cognitive impairment in MS, before it becomes an established and irreversible entity.

Missingness of Height Data from the Demographic and Health Surveys in Africa between 1991 and 2016 Was Not Random but Is Unlikely to Have Major Implications for Biases in Estimating Stunting Prevalence or the Determinants of Child Height

Background

Obtaining accurate information on child height is essential for targeting interventions to reduce stunting. Thus, large-scale nutrition surveys must ensure that samples are representative of underlying populations of interest. Without accurate representation, resources for combating child stunting may be inefficiently allocated.

Objective

This study examined differences between children with (92.7%) and without (7.3%) complete and biologically plausible height data available from the Demographic and Health Surveys.

Methods

A total of 116 Demographic and Health Surveys conducted between 1991 and 2016 from 35 countries in sub-Saharan Africa were merged. Differences between children with and without biologically plausible height data were examined with the use of chi-square tests, t tests, and bivariate and multivariate logistic regression with survey cluster-level fixed effects.

Results

Of the whole sample, 97.9% of children had complete height data and 92.7% of children had complete and biologically plausible height data. There were sociodemographic and socioeconomic differences between those with and those without complete and biologically plausible height data. Children with usable height data were more likely to have a health card seen by the survey enumerator [mean height-for-age z score (HAZ): -1.32] than not (mean HAZ: -1.44) (P < 0.001), be older (mean HAZ: -1.63) than younger (mean HAZ: -1.11) (P < 0.001), have been ill in the previous 2 wk (mean HAZ: -1.43) than not ill (mean HAZ: -1.33) (P < 0.001), live in urban areas (mean HAZ: -1.13) than in rural areas (mean HAZ: -1.44) (P < 0.001), have literate mothers (mean HAZ: -1.16) than illiterate mothers (mean HAZ: -1.53) (P < 0.001), have mothers with more education (mean HAZ: -1.23) than not (mean HAZ: -1.54) (P < 0.001), and have more household wealth (mean HAZ: -0.82) than not (mean HAZ: -1.56) (P = 0.038).

Conclusions

Missing data from the DHS anthropometry questionnaires may affect research on child height, but overall effects are likely small. Given the trends in nutritional epidemiology toward the use of large-scale national surveys, understanding the ways in which biases arise as sample sizes increase is essential.

Neuraxial analgesia is not associated with an increased risk of post-partum relapses in MS

Background:

Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses.

Objective:

To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy.

Methods:

We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis.

Results:

A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78).

Conclusion:

Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

Peripheral Neuropathy in Hypothyroidism - an Association with Spurious Polycythemia (Gaisbock's Syndrome)1

The neurological complications of hypothyroidism, including dementia, cerebellar ataxia, myopathy and entrapment neuropathy, are well recorded, but peripheral neuropathy has rarely been documented (Swanson et al. 1981). In this paper two patients are described who developed myxoedema and peripheral neuropathy. The first patient had a very rapid onset of myxoedema, and during observation he developed spurious polycythemia (Gaisbock's syndrome) over a period of nine days.

Stopping beta-interferon therapy in multiple sclerosis: an analysis of stopping patterns

Estimates of the beta-interferon (IFNB) stopping rate in relapsing-remitting multiple sclerosis (RRMS) and secondary progressive MS (SPMS) vary and have been mainly derived from multicentre studies. This is a retrospective, hospital chart-based study of 394 patients treated by a single neurologist for up to eight years. The aims of the study were to ascertain the frequency and timing of IFNβ discontinuation in a well supported cohort, and to investigate whether the clinical disease type at the initiation of IFNβ or the reason for discontinuation influenced stopping rates. The median follow-up was 49 months. The overall IFNβ stopping rate was 28% over five years; there was a significant difference between the IFNβ stopping rates for RRMS (14%) and SPMS (23%) after three years of follow-up (P=0.0003). Patients stopped IFNβ due to side effects after a median of 13 months, and due to failure of therapy after a median of 35 months (P=0.0004). Significantly more patients with SPMS than with RRMS stopped IFNβ due to treatment failure (P=0.037). Conclusion: IFNβ discontinuation occurred earlier in the treatment course when due to side effects. Stopping IFNβ therapy was more common in SPMS and was more often due to treatment failure than side effects.

The Face-Symbol Test and the Symbol-Digit Test are not reliable surrogates for the Paced Auditory Serial Addition Test in multiple sclerosis

The Paced Auditory Serial Addition Test (PASAT) is the chosen task for cognitive assessment in the multiple sclerosis functional composite (MSFC) and a widely used task in neuropsychological studies of people with multiple sclerosis (MS), but is unpopular with patients. The Face-Symbol Test (FST) and Symbol-Digit Tests (SDT) are alternative methods of cognitive testing in MS, which are easily administered and patient-friendly. In order to evaluate the potential of the FST as a possible surrogate for the PASAT, we directly compared the FST to the PASAT and the SDT in a cohort of 50 MS patients with varying levels of disability. There was significant correlation between SDT and FST scores (Spearman’s rho 0.80, 95% CI 0.66 - 0.88), R2 65%, with moderate inter-test agreement (κ = 0.52). In contrast, SDT and FST scores were less predictive of PASAT scores. We concluded that neither the FST nor SDT are reliable surrogates for the PASAT.

Preterm neonatal morbidity and mortality by gestational age: a contemporary cohort

BACKGROUND

Although preterm birth <37 weeks' gestation is the leading cause of neonatal morbidity and mortality in the United States, the majority of data regarding preterm neonatal outcomes come from older studies, and many reports have been limited to only very preterm neonates. Delineation of neonatal outcomes by delivery gestational age is needed to further clarify the continuum of mortality and morbidity frequencies among preterm neonates.

OBJECTIVE

We sought to describe the contemporary frequencies of neonatal death, neonatal morbidities, and neonatal length of stay across the spectrum of preterm gestational ages.

STUDY DESIGN

This was a secondary analysis of an obstetric cohort of 115,502 women and their neonates who were born in 25 hospitals nationwide, 2008 through 2011. All liveborn nonanomalous singleton preterm (23.0-36.9 weeks of gestation) neonates were included in this analysis. The frequency of neonatal death, major neonatal morbidity (intraventricular hemorrhage grade III/IV, seizures, hypoxic-ischemic encephalopathy, necrotizing enterocolitis stage II/III, bronchopulmonary dysplasia, persistent pulmonary hypertension), and minor neonatal morbidity (hypotension requiring treatment, intraventricular hemorrhage grade I/II, necrotizing enterocolitis stage I, respiratory distress syndrome, hyperbilirubinemia requiring treatment) were calculated by delivery gestational age; each neonate was classified once by the worst outcome for which criteria was met.

RESULTS

In all, 8334 deliveries met inclusion criteria. There were 119 (1.4%) neonatal deaths. In all, 657 (7.9%) neonates had major morbidity, 3136 (37.6%) had minor morbidity, and 4422 (53.1%) survived without any of the studied morbidities. Deaths declined rapidly with each advancing week of gestation. This decline in death was accompanied by an increase in major neonatal morbidity, which peaked at 54.8% at 25 weeks of gestation. As frequencies of death and major neonatal morbidity fell, minor neonatal morbidity increased, peaking at 81.7% at 31 weeks of gestation. The frequency of all morbidities fell >32 weeks. After 25 weeks, neonatal length of hospital stay decreased significantly with each additional completed week of pregnancy; among babies delivered from 26-32 weeks of gestation, each additional week in utero reduced the subsequent length of neonatal hospitalization by a minimum of 8 days. The median postmenstrual age at discharge nadired around 36 weeks' postmenstrual age for babies born at 31-35 weeks of gestation.

CONCLUSION

Our data show that there is a continuum of outcomes, with each additional week of gestation conferring survival benefit while reducing the length of initial hospitalization. These contemporary data can be useful for patient counseling regarding preterm outcomes.

Management of dystonia in Europe: a survey of the European network for the study of the dystonia syndromes

BACKGROUND AND PURPOSE

Dystonia is difficult to recognize due to its large phenomenological complexity. Thus, the use of experts in dystonia is essential for better recognition and management of dystonia syndromes (DS). Our aim was to document managing strategies, facilities and expertise available in various European countries in order to identify which measures should be implemented to improve the management of DS.

METHODS

A survey was conducted, funded by the Cooperation in Science and Technology, via the management committee of the European network for the study of DS, which is formed from representatives of the 24 countries involved.

RESULTS

Lack of specific training in dystonia by general neurologists, general practitioners as well as other allied health professionals was universal in all countries surveyed. Genetic testing for rare dystonia mutations is not readily available in a significant number of countries and neurophysiological studies are difficult to perform due to a lack of experts in this field of movement disorders. Tetrabenazine is only readily available for treatment of dystonia in half of the surveyed countries. Deep brain stimulation is available in three-quarters of the countries, but other surgical procedures are only available in one-quarter of countries.

CONCLUSIONS

Internationally, collaboration in training, advanced diagnosis, treatment and research of DS and, locally, in each country the creation of multidisciplinary teams for the management of dystonia patients could provide the basis for improving all aspects of dystonia management across Europe.

Short Communication: Inhibition of DC-SIGN-Mediated HIV-1 Infection by Complementary Actions of Dendritic Cell Receptor Antagonists and Env-Targeting Virus Inactivators

The DC-SIGN receptor on human dendritic cells interacts with HIV gp120 to promote both infection of antigen-presenting cells and transinfection of T cells. We hypothesized that in DC-SIGN-expressing cells, both DC-SIGN ligands such as dextrans and gp120 antagonists such as peptide triazoles would inhibit HIV infection with potential complementary antagonist effects. To test this hypothesis, we evaluated the effects of dextran (D66), isomaltooligosaccharides (D06), and several peptide triazoles (HNG156, K13, and UM15) on HIV infection of B-THP-1/DC-SIGN cells. In surface plasmon resonance competition assays, D66 (IC50 = 35.4 μM) and D06 (IC50 = 3.4 mM) prevented binding of soluble DC-SIGN to immobilized mannosylated bovine serum albumin (BSA). An efficacious dose-dependent inhibition of DC-SIGN-mediated HIV infection in both pretreatment and posttreatment settings was observed, as indicated by inhibitory potentials (EC50) [D66 (8 μM), D06 (48 mM), HNG156 (40 μM), UM15 (100 nM), and K13 (25 nM)]. Importantly, both dextrans and peptide triazoles significantly decreased HIV gag RNA levels [D66 (7-fold), D06 (13-fold), HNG156 (7-fold), K-13 (3-fold), and UM15 (6-fold)]. Interestingly, D06 at the highest effective concentration showed a 14-fold decrease of infection, while its combination with 50 μM HNG156 showed a 26-fold decrease. Hence, these compounds can combine to inactivate the viruses and suppress DC-SIGN-mediated virus-cell interaction that as shown earlier leads to dendritic cell HIV infection and transinfection dependent on the DC-SIGN receptor.

A 10-year follow-up of the European multicenter trial of interferon β-1b in secondary-progressive multiple sclerosis

OBJECTIVES

To explore long-term effects of treatment and prognostic relevance of variables assessed at baseline and during the European secondary progressive multiple sclerosis (SPMS) trial of interferon beta 1b (IFNB-1b).

METHODS

We assessed 362 patients (60% female; median age 41 years; Expanded Disability Status Scale (EDSS): 5.5; 51% randomized to IFNB-1b) for their EDSS and treatment history after 10 years. Non-parametric analysis of covariance (ANCOVA) and multivariate linear regression models were applied.

RESULTS

Median EDSS was 6.0 at the end of the randomized controlled trial (RCT), in the IFNB-1b and placebo groups, and 7.0 in long-term follow-up patients (those receiving IFNB-1b in the RCT were 6.5 and those receiving placebo in the RCT were 7.0; p = 0.086). 24 patients (6.6%) were deceased. The EDSS at baseline and the EDSS change during the RCT were the most important predictors of the EDSS 10 years later (partial R(2): 0.47). The ability to predict changes in EDSS 10 years after the RCT was limited (R(2): 0.12). Magnetic resonance imaging (MRI) measures remained in the predictive models, but explained < 5% of the variability.

CONCLUSIONS

The results from this analysis did not provide convincing evidence to support a favorable long-term outcome in those patients allocated IFNB-1b during the RCT, in our SPMS cohort. The progressive stage of the disease remains largely unpredictable by clinical and conventional MRI measures, so better prognostic markers are needed.

Nonmedically indicated induction vs expectant treatment in term nulliparous women

OBJECTIVE

The purpose of this study was to compare maternal and neonatal outcomes in nulliparous women with nonmedically indicated inductions at term vs those expectantly treated.

STUDY DESIGN

Data were obtained from maternal and neonatal charts for all deliveries on randomly selected days across 25 US hospitals over a 3-year period. A low-risk subset of nulliparous women with vertex nonanomalous singleton gestations who delivered 38 0/7 to 41 6/7 weeks were selected. Maternal and neonatal outcomes for nonmedically indicated induction within each week were compared with women who did not undergo nonmedically indicated induction during that week. Multivariable analysis was used to adjust for hospital, maternal age, race/ethnicity, body mass index, cigarette use, and insurance status.

RESULTS

We found 31,169 women who met our criteria. Neonatal complications were either less frequent with nonmedically indicated induction or no different between groups. Nonmedically indicated induction was associated with less frequent peripartum infections (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.16-0.98) at 38 weeks of gestation and less frequent third- and fourth-degree lacerations (OR, 0.60; 95% CI, 0.42-0.86) and less frequent peripartum infections (OR, 0.66; 95% CI, 0.49-0.90) at 39 weeks of gestation. Nonmedically indicated induction was associated with a longer admission-to-delivery time by approximately 3-4 hours and increased odds of cesarean delivery at 38 (OR, 1.50; 95% CI, 1.08-2.08) and 40 weeks (OR, 1.30; 95% CI, 1.15-1.46) of gestation.

CONCLUSION

At 39 weeks of gestation, nonmedically indicated induction is associated with lower maternal and neonatal morbidity than women who are expectantly treated.

Natalizumab improves ambulation in relapsing-remitting multiple sclerosis: results from the prospective TIMER study and a retrospective analysis of AFFIRM

Background and purpose

Impaired ambulation is a prominent disabling symptom of multiple sclerosis and can lead to reduced quality of life. Whether natalizumab, a monoclonal antibody shown to reduce disease activity in relapsing−remitting multiple sclerosis, could impact ambulation performance was examined.

Methods

A prospective open-label study, TIMER, was conducted in natalizumab-naive patients (n = 215). The timed 25-foot walk (T25FW) and timed 100-m walk (T100MW) were assessed at baseline and at weeks 24 and 48 of natalizumab therapy, together with Expanded Disability Status Scale scores. The effects of natalizumab on T25FW performance were also examined in a retrospective analysis of natalizumab-treated patients (n = 627) and placebo control patients (n = 315) from the AFFIRM study.

Results

In TIMER, a significant increase from baseline in T25FW speed was seen at week 24 (P = 0.0074) and in T100MW speed at weeks 24 and 48 (both P < 0.001). A greater proportion of patients showed clinically meaningful increases (≥20%) in walking speed on the T100MW (25%) than on the T25FW (13%) at week 48 (P = 0.032). In AFFIRM, natalizumab increased the proportion of patients with ≥20% confirmed improvement in T25FW speed at year 2 by 78% versus placebo (P = 0.0133).

Conclusions

Natalizumab increased walking speed in patients with relapsing−remitting multiple sclerosis. The T100MW may be more sensitive to changes in ambulation capacity than the T25FW, and both tests appear to detect clinically meaningful improvements in ambulatory function.

Evaluating evolutionary history in the face of high gene tree discordance in Australian Gehyra (Reptilia: Gekkonidae)

Species tree methods have provided improvements for estimating species relationships and the timing of diversification in recent radiations by allowing for gene tree discordance. Although gene tree discordance is often observed, most discordance is attributed to incomplete lineage sorting rather than other biological phenomena, and the causes of discordance are rarely investigated. We use species trees from multi-locus data to estimate the species relationships, evolutionary history and timing of diversification among Australian Gehyra-a group renowned for taxonomic uncertainty and showing a large degree of gene tree discordance. We find support for a recent Asian origin and two major clades: a tropically adapted clade and an arid adapted clade, with some exceptions, but no support for allopatric speciation driven by chromosomal rearrangement in the group. Bayesian concordance analysis revealed high gene tree discordance and comparisons of Robinson-Foulds distances showed that discordance between gene trees was significantly higher than that generated by topological uncertainty within each gene. Analysis of gene tree discordance and incomplete taxon sampling revealed that gene tree discordance was high whether terminal taxon or gene sampling was maximized, indicating discordance is due to biological processes, which may be important in contributing to gene tree discordance in many recently diversified organisms.

Trisulfide modification impacts the reduction step in antibody-drug conjugation process

Antibody-drug conjugates (ADCs) utilizing cysteine-directed linker chemistry have cytotoxic drugs covalently bound to native heavy-heavy and heavy-light interchain disulfide bonds. The manufacture of these ADCs involves a reduction step followed by a conjugation step. When tris(2-carboxyethyl)phosphine (TCEP) is used as the reductant, the reaction stoichiometry predicts that for each molecule of TCEP added, one interchain disulfide should be reduced, generating two free thiols for drug linkage. In practice, the amount of TCEP required to achieve the desired drug-to-antibody ratio often exceeds the predicted, and is variable for different lots of monoclonal antibody starting material. We have identified the cause of this variability to be inconsistent levels of interchain trisulfide bonds in the monoclonal antibody. We propose that TCEP reacts with each trisulfide bond to form a thiophosphine and a disulfide bond, yielding no net antibody free thiols for conjugation. Antibodies with higher levels of trisulfide bonds require a greater TCEP:antibody molar ratio to achieve the targeted drug-to-antibody ratio.

A proposed modification to the McDonald 2010 criteria for the diagnosis of primary progressive multiple sclerosis

Background:

The diagnostic criteria for primary–progressive multiple sclerosis (PPMS) have undergone revision over the last 20 years. Cerebrospinal fluid oligoclonal bands (CSFOBs) have received less emphasis in recent revisions of the McDonald criteria. The aim of this study was to examine the sensitivity of the diagnostic criteria for PPMS with particular reference to spinal cord criteria and examine the utility of CSFOBs in a cohort of PPMS patients.

Methods:

All new PPMS diagnoses between 1990 and 2011 were identified. Baseline clinical details and paraclinical evaluations including MRI of the brain, spinal cord, CSF and visually evoked responses (VERs) were assessed. The proportion of patients who met the requirements for diagnosis of PPMS on the basis of Thompson’s and the McDonald Criteria (2001, 2005, 2010) were determined.

Results:

There were 88/95 PPMS patients who had at least two diagnostic investigations. The sensitivity of Thompson’s and the McDonald 2001 criteria was 64%; the McDonald 2010 revisions gave the highest sensitivity (77%); the McDonald 2005 criteria had intermediate sensitivity (74%). The combination of CSFOBs and MRI of the brain yielded the greatest number of patients demonstrating dissemination in space (DIS) on only two investigations. VERs did not aid diagnosis. Reducing requirements for the number of spinal cord lesions (symptomatic or not) to one increased diagnostic sensitivity to 84%.

Conclusion:

An alternative criterion requiring two of: i) MRI of the brain with one or more lesions in two of three regions typical for demyelination; ii) the presence of one T2-weighted spinal cord plaque (typical for demyelination); iii) CSFOBs; would increase the diagnostic sensitivity for PPMS.