School Closure and Child Maltreatment During the COVID-19 Pandemic

It is not known how school closure affected child maltreatment. We conducted a retrospective cohort, linear mixed-models study of 133 counties (comprising 8,582,479 children) in Virginia between 2018 and 2021. Exposure was the opening of schools at least 2 days a week. Outcomes were referrals and incidence of child maltreatment reported to the Department of Social Services. In 2020-2021, there were descriptively more referrals (in-person: 50.9 per 10,000 [95% CI: 47.9, 54.0]; virtual: 45.8 per 10,000 [95% CI: 40.7, 50.9]) and incidence (in-person: 3.7 per 10,000 [95% CI: 3.3, 4.2]; virtual: 2.9 per 10,000 [95% CI: 2.3, 3.5]) of child maltreatment in counties with in-person schooling, though these differences did not reach statistical significance. The referral rate variations (between pandemic and pre-pandemic eras) of counties with in-person schooling was significantly greater than rate changes in counties with virtual schooling during the summer period. There were no differences in incidence in any quarter. Higher poverty within a county was associated with both higher referrals and incidence. Our findings suggest that child maltreatment is driven primarily by underlying differences in counties (namely, poverty) rather than the type of schooling children receive.

Efficient management of new patient referrals to a breast service: the safe introduction of an advanced nurse practitioner-led telephone breast pain service

INTRODUCTION

There has been an almost 100% increase in referrals to breast cancer diagnostic clinics in the past decade. Breaching of the two-week cancer referral target is now commonplace, potentially delaying diagnoses of breast malignancy in many women. Almost one in five of these referrals are women with mastalgia, not a symptom linked to breast cancer. The objective of the study was the safe introduction of an advanced nurse practitioner-led telephone service for women with mastalgia to improve the service for women and create capacity for those with "red flag" breast symptoms.

METHODS

Referrals to clinic were triaged, women with mastalgia only were directed to a telephone-based assessment clinic and symptoms evaluated using a multidisciplinary created proforma.

RESULTS

Within 23 months, 1,427 women were assessed in the breast pain telephone assessment clinic: 863 (61%) were aged over 40 and 564 (39%) aged under 40. A total of 1,238 underwent telephone assessment. Reassurance and discharge only was needed for 365 (26%). The aetiology of pain was identified as musculoskeletal in 1,104/1,238 (89%) of patients, with only 39/1,238 (3.2%) identified as having true breast pain. Additional symptoms were mentioned by 264 women (18%) during the consultation; all immediately redirected back to a diagnostic clinic. Mammography was undertaken in 609 women (43%). Seven women (0.6%) were diagnosed with a breast malignancy. Patient survey indicated that 93% of patients were satisfied with the care received and 97% said they would recommend the service to a family member or friend.

CONCLUSIONS

Although face-to-face assessments for breast pain remain the standard practice in many breast units, data indicating the safety of a telephone assessment clinic, along with high levels of patient satisfaction, question whether services can be delivered differently.

Demographic composition, not demographic diversity, predicts biomass and turnover across temperate and tropical forests

The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1961 tree species from temperate and tropical forests and evaluate how demographic diversity (DD) and demographic composition (DC) differ across forests, and how these differences in demography relate to species richness, aboveground biomass (AGB), and carbon residence time. We find wide variation in DD and DC across forest plots, patterns that are not explained by species richness or climate variables alone. There is no evidence that DD has an effect on either AGB or carbon residence time. Rather, the DC of forests, specifically the relative abundance of large statured species, predicted both biomass and carbon residence time. Our results demonstrate the distinct DCs of globally distributed forests, reflecting biogeography, recent history, and current plot conditions. Linking the DC of forests to resilience or vulnerability to climate change, will improve the precision and accuracy of predictions of future forest composition, structure, and function.

The SARS-CoV-2 Spike protein alters human cardiac pericyte function and interaction with endothelial cells through a non-infective mechanism involving activation of CD147 receptor signalling

Background

Human cardiac pericytes (PC) were proposed as the main cellular target for SARS-CoV-2 in the heart due to high transcriptional levels of the angiotensin-converting enzyme 2 (ACE2) receptor. Emerging reports indicate CD147/Basigin (BSG), highly expressed in endothelial cells (EC), is an alternative SARS-CoV-2 receptor. To date, the mechanism by which the virus infects and disrupts the heart vascular cells was not identified yet. Moreover, cleaved Spike (S) protein molecules could be released into the bloodstream from the leaking pulmonary epithelial-endothelial barrier in patients with severe COVID-19, opening to the possibility of non-infective diseases in organs distant from the primary site of infection.

Purposes

(1) to confirm that human primary cardiac PC express ACE2 and CD147; (2) to verify if PC are permissible to SARS-CoV-2 infection; (3) to investigate if the recombinant SARS-CoV-2 S protein alone, without the other viral elements, can trigger molecular signalling and induce functional alterations in PC; (4) to explore which viral receptor is responsible for the observed events.

Methods and results

Cardiac PC express both the ACE2 and CD147 receptors at mRNA and protein level. Incubation of PC for up to 5 days with SARS-CoV-2 expressing the green fluorescent protein (GFP) did not show any evidence of cell infection or viral replication. Next, we exposed the PC to the recombinant S protein (5.8 nM) and confirmed that the protein engaged with cellular receptors (western blot analysis of S protein in treated and control PC). Incubation with the S protein increased PC migration (wound closure assay, P<0.01 vs ctrl) and reduced the formation of tubular structures between PC and EC in a Matrigel assay (P<0.01 vs ctrl). Moreover, the S protein promoted the production of pro-inflammatory factors typical of the cytokine storm in PC (ELISA measurement of MCP1, IL-6, IL-1β, TNFα, P<0.05 vs ctrl), and induced the secretion of pro-apoptotic factors responsible for EC death (Caspase 3/7 assay, P<0.05 vs ctrl). Signalling studies revealed that the S protein triggers the phosphorylation/activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) through the CD147 receptor, but not ACE2, in cardiac PC. The neutralization of CD147, using a blocking antibody, prevented ERK1/2 activation in PC, and was reflected into a partial rescue of the cell functional behaviour (migration and pro-angiogenic capacity). In contrast, blockage of CD147 failed to prevent the pro-inflammatory response in PC.

Conclusions

We propose the novel hypothesis that COVID-19 associated heart's microvascular dysfunction is prompted by circulating S protein molecules rather than by the direct coronavirus infection of PC. Besides, we propose CD147, and not ACE2, as the leading receptor mediating S protein signalling in cardiac PC.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): BHF project grant “Targeting the SARS-CoV-2 S-protein binding to the ACE2 receptor to preserve human cardiac pericytes function in COVID-19” BHF Centre for Vascular Regeneration II

A Cluster Randomized Trial to Reduce Missed Abusive Head Trauma in Pediatric Intensive Care Settings

OBJECTIVE

To estimate the impact of the PediBIRN (Pediatric Brain Injury Research Network) 4-variable clinical decision rule (CDR) on abuse evaluations and missed abusive head trauma in pediatric intensive care settings.

STUDY DESIGN

This was a cluster randomized trial. Participants included 8 pediatric intensive care units (PICUs) in US academic medical centers; PICU and child abuse physicians; and consecutive patients with acute head injures <3 years (n = 183 and n = 237, intervention vs control). PICUs were stratified by patient volumes, pair-matched, and randomized equally to intervention or control conditions. Randomization was concealed from the biostatistician. Physician-directed, cluster-level interventions included initial and booster training, access to an abusive head trauma probability calculator, and information sessions. Outcomes included "higher risk" patients evaluated thoroughly for abuse (with skeletal survey and retinal examination), potential cases of missed abusive head trauma (patients lacking either evaluation), and estimates of missed abusive head trauma (among potential cases). Group comparisons were performed using generalized linear mixed-effects models.

RESULTS

Intervention physicians evaluated a greater proportion of higher risk patients thoroughly (81% vs 73%, P = .11) and had fewer potential cases of missed abusive head trauma (21% vs 32%, P = .05), although estimated cases of missed abusive head trauma did not differ (7% vs 13%, P = .22). From baseline (in previous studies) to trial, the change in higher risk patients evaluated thoroughly (67%→81% vs 78%→73%, P = .01), and potential cases of missed abusive head trauma (40%→21% vs 29%→32%, P = .003), diverged significantly. We did not identify a significant divergence in the number of estimated cases of missed abusive head trauma (15%→7% vs 11%→13%, P = .22).

CONCLUSIONS

PediBIRN-4 CDR application facilitated changes in abuse evaluations that reduced potential cases of missed abusive head trauma in PICU settings.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03162354.

127 A Student Pilot For A Feasibility Study of the Theoretical 3S Trial (SPFT3S): Patient Questionnaire and Demographics

Introduction

There is conflicting evidence on the benefit of statins for primary prevention of cardiovascular disease (CVD) in non-diabetics over 75. Emerging evidence shows they may be ineffective, yet current guidance supports their use in those up to 85. The objectives of this study were to assess patients’ understanding of statins, willingness to participate in a theoretical randomised controlled trial (RCT), where they would be randomised to stop their statin and to compare the trial population with national data.

Methods

The survey took place in 8 GP practices with 4 students involved in questionnaire distribution. A patient search identified those over 75 and on a statin. Patients were excluded if they had a history of CVD or diabetes. 36 patients were identified and completed questionnaires, 5 were removed because they reported exclusion criteria. Demographic data was compared to the UK population from the 2011 census.

Results

Of 31 participants, 71% understood why they took statins, most were unconcerned about side effects and only 1 patient stopped statins due to the media. Opinions on the theoretical “stopping statins trial” were varied. 35% of people responded positively. 29% would not want to take part and 36% of people were unsure. Comparison of our trial population against the national population shows that 903,505 people would be eligible for a UK trial.

Conclusions

The purpose of this exercise was to see if patients would be willing to participate in a trial where 50% stopped taking their statin. Approximately a third said yes and only a third said no. As there are nearly a million people in this population, it suggests a fully funded, larger-scale feasibility study of this theoretical randomised control trial is warranted.

126 A Student Pilot for A Feasibility Study of the Theoretical 3S Trial (SPFT3S): GP and Ethics Committee Members Questionnaire

Introduction

Emerging research suggests that statin use for primary prevention in people without diabetes aged 75 and older has no benefit. This study aims to determine the feasibility of the theoretical Stop Statin Study (3S), a double-blind randomised controlled trial carried out in general practice, which would test this hypothesis. 50% of trial patients would stop taking statins for 5 years in an event driven study. The questionnaires aim to identify the attitudes of general practitioners (GPs) and ethics committee members (ECMs) regarding stopping statins for 5 years in patients aged 75 and older without diabetes or history of cardiovascular disease and their willingness to allow patients to participate in the 3S study.

Method

Questionnaires comprised of 6 questions were designed. 4 students distributed the questionnaire and it was completed by 19 GPs based at 8 practices in the North-East of England. 31 ECMs (12 expert and 19 lay) responded by email.

Results

95% of GPs who completed the survey would agree to their patients participating in the theoretical study with 47% of GPs indicating that their willingness to participate in the study is patient dependent. 95% of GPs would also consider stopping statins in this population group if sufficient research had been carried out or if the guidelines were changed. 42% of GPs have a negative attitude to prescribing statins in this population group. All the ECMs would approve the study, citing over-prescribing and polypharmacy as their reason.

Conclusions

The majority of GPs will participate in the theoretical 3S study, if their patients are willing to participate. There is already a negative perception amongst GPs towards the use of statins in elderly people without disease. The 3S study appears to be feasible from the GP and ethics perspective but would require a larger feasibility study.

Developing and testing a principle-based fidelity index for peer support in mental health services

PURPOSE

Evidence suggests that the distinctive relational qualities of peer support-compared to clinical-patient relationships-can be eroded in regulated healthcare environments. Measurement of fidelity in trials of peer support is lacking. This paper reports the development and testing of a fidelity index for one-to-one peer support in mental health services, designed to assess fidelity to principles that characterise the distinctiveness of peer support.

METHODS

A draft index was developed using expert panels of service user researchers and people doing peer support, informed by an evidence-based, peer support principles framework. Two rounds of testing took place in 24 mental health services providing peer support in a range of settings. Fidelity was assessed through interviews with peer workers, their supervisors and people receiving peer support. Responses were tested for spread and internal consistency, independently double rated for inter-rater reliability, with feedback from interviewees and service user researchers used to refine the index.

RESULTS

A fidelity index for one-to-one peer support in mental health services was produced with good psychometric properties. Fidelity is assessed in four principle-based domains; building trusting relationships based on shared lived experience; reciprocity and mutuality; leadership, choice and control; building strengths and making connections to community.

CONCLUSIONS

The index offers potential to improve the evidence base for peer support in mental health services, enabling future trials to assess fidelity of interventions to peer support principles, and service providers a means of ensuring that peer support retains its distinctive qualities as it is introduced into mental health services.

Follow-up of renal impairment results among attendees taking HIV Pre-Exposure Prophylaxis at a Sydney Sexual Health Clinic

Renal monitoring is recommended for Pre-Exposure Prophylaxis (PrEP) users. We aimed to explore follow-up and outcomes among PrEP users with renal impairment (defined as estimated glomerular filtration rate <65 mL/min/1.73 m²) attending Sydney Sexual Health Centre. Time to follow-up was analysed for impairment results over a 12-month period (January-December 2018); 48/2504 (1.9%) tests among 1700 attendees showed impairment. Follow-up occurred in 39/48 (81.3%) impairment results after a median of 42 days. PrEP was ceased in 3/6 cases of non-resolving/persisting impairment, with one case of subsequent human immunodeficiency virus infection. Maintaining engagement and follow-up of those with renal impairment are important aspects of PrEP service provision.

Modified Immunodiffusion Method for Detection of Salmonella in Raw Flesh and Highly Contaminated Foods: Collaborative Study

A total of 19 government and private industry laboratories in Canada and the United States participated in the collaborative study. Naturally contaminated ground poultry and animal meals, as well as inoculated raw shrimp, were examined for presence of Salmonella by both the modified immunodiffusion method and the Bacteriological Analytical Manual culture method, resulting in an agreement rate of 93.1%. The 2 methods are statistically equivalent for all food types at each inoculation level and for all lots of naturally contaminated foods evaluated in this study. The modification of the AOAC Official Method 989.13, immunodiffusion (1–2 TEST) method for detection of motile Salmonella in all foods, has been adopted revised first action by AOAC INTERNATIONAL.

The Forest Observation System, building a global reference dataset for remote sensing of forest biomass

Forest biomass is an essential indicator for monitoring the Earth's ecosystems and climate. It is a critical input to greenhouse gas accounting, estimation of carbon losses and forest degradation, assessment of renewable energy potential, and for developing climate change mitigation policies such as REDD+, among others. Wall-to-wall mapping of aboveground biomass (AGB) is now possible with satellite remote sensing (RS). However, RS methods require extant, up-to-date, reliable, representative and comparable in situ data for calibration and validation. Here, we present the Forest Observation System (FOS) initiative, an international cooperation to establish and maintain a global in situ forest biomass database. AGB and canopy height estimates with their associated uncertainties are derived at a 0.25 ha scale from field measurements made in permanent research plots across the world's forests. All plot estimates are geolocated and have a size that allows for direct comparison with many RS measurements. The FOS offers the potential to improve the accuracy of RS-based biomass products while developing new synergies between the RS and ground-based ecosystem research communities.

Malignant transformation of tailgut cysts is significantly higher than previously reported: systematic review of cases in the literature

AIM

The best treatment for tailgut cysts has not been firmly established. We report a systematic review of the cases in the available literature in order to provide an evidence base for treatment.

METHOD

A systematic search of articles wholly or partly in English was made of PubMed, Embase and Google Scholar; additional studies were discovered by searching reference lists and contacting authors directly. Search terms 'tailgut cyst', 'tail gut cyst', 'retrorectal hamartoma' and 'retrorectal tumour' were used for case reports or case series; no publication date restrictions were imposed. Only studies with histological confirmation of diagnosis and reporting the age and gender of patients were included. Papers were excluded by consensus between the first two authors.

RESULTS

A total of 196 individual cases were analysed in detail including 51 cases of neoplasia. The overall rate of neoplastic transformation was 26.6%. Although the male:female cyst incidence ratio was 1:4, men over 18 had a significantly greater relative risk of neoplasm at 1.94 (P = 0.0055). Radiological evidence of nodular thickening of the cyst wall significantly increased the relative risk of the presence of cancer (P = 0.0023).

CONCLUSIONS

Current orthodoxy that these are not dangerous embryological remnants is unfounded and may be false. The available data suggest the risk of malignant transformation is high and will apply to any residual tissue after excision. The same rationale behind total mesorectal excision in rectal cancer applies to tailgut cysts. Consequently they should be resected with similar oncological margins.

Racial and Ethnic Disparities and Bias in the Evaluation and Reporting of Abusive Head Trauma

OBJECTIVE

To characterize racial and ethnic disparities in the evaluation and reporting of suspected abusive head trauma (AHT) across the 18 participating sites of the Pediatric Brain Injury Research Network (PediBIRN). We hypothesized that such disparities would be confirmed at multiple sites and occur more frequently in patients with a lower risk for AHT.

STUDY DESIGN

Aggregate and site-specific analysis of the cross-sectional PediBIRN dataset, comparing AHT evaluation and reporting frequencies in subpopulations of white/non-Hispanic and minority race/ethnicity patients with lower vs higher risk for AHT.

RESULTS

In the PediBIRN study sample of 500 young, acutely head-injured patients hospitalized for intensive care, minority race/ethnicity patients (n = 229) were more frequently evaluated (P < .001; aOR, 2.2) and reported (P = .001; aOR, 1.9) for suspected AHT than white/non-Hispanic patients (n = 271). These disparities occurred almost exclusively in lower risk patients, including those ultimately categorized as non-AHT (P = .001 [aOR, 2.4] and P = .003 [aOR, 2.1]) or with an estimated AHT probability of ≤25% (P <.001 [aOR, 4.1] and P <.001 [aOR, 2.8]). Similar site-specific analyses revealed that these results reflected more extreme disparities at only 2 of 18 sites, and were not explained by local confounders.

CONCLUSION

Significant race/ethnicity-based disparities in AHT evaluation and reporting were observed at only 2 of 18 sites and occurred almost exclusively in lower risk patients. In the absence of local confounders, these disparities likely represent the impact of local physicians' implicit bias.

Abstract MIP-071: TARGETING A CHEMORESISTANT OVARIAN CANCER CELL POPULATION VIA THE CARBOHYDRATE ANTIGEN SIALYL TN

Key words: Sialyl Tn, drug resistance, antibody-drug conjugates, cancer stem cells

OBJECTIVES: A successful therapeutic strategy for ovarian cancer will require direct targeting of inherently chemoresistant tumor cells which are comprised in part of cancer stem cells (CSCs) that survive current cytotoxic treatment regimes and drive tumor resurgence. The sialyl-Tn (STn) antigen is a carbohydrate moiety present on tumor cells but rarely seen in normal adult tissue. Importantly, STn has been shown to be present on CSCs in pancreatic, colon, and gastric malignancies. Our objective was to assess the expression of STn and the known CSC marker CD133 in human ovarian cancer (OvCa) cell lines and primary serous carcinomas, and evaluate the ability of STn+ and STn- cells to both grow in an anchorage independent manner and survive standard-of-care cytotoxic therapy. Furthermore, we sought to assess the effect of murine and humanized α -STn antibody-drug conjugates (ADCs) on OvCa cells in vitro and tumor viability in vivo.

METHODS: STn and CD133 expression in established OvCa cell lines was analyzed by flow cytometry. STn-CD133-, STn+CD133-, STn-CD133+ and STn+CD133+ cells were purified from OVCAR3 and OVCAR4 by FACS, plated in soft agar, and incubated for 21 days. Colony forming efficiency of each sub-population was calculated. Unsorted cells were treated in vitro with either murine α -STn-monomethyl auristatin E (MMAE) ADC or vehicle control and cell viability was assessed by MTT assay. Subsequently, cells were treated in vitro with α -STn-MMAE, paclitaxel and carboplatin, or appropriate controls, and the profile of cells surviving 72 hours post-treatment was determined by flow cytometric analysis. Finally, OVCAR3-derived mouse xenografts were treated with murine and humanized α-STn-MMAE, unconjugated mAbs alone, and vehicle control. Mice were assessed regularly for tumor growth and cytotoxic effects.

RESULTS: In the OvCa cell lines OV90, OVCAR3 and OVCAR4, when grown in traditional 2D culture, STn+ cells comprised 98.4%, 40.0%, and 26.4% of the total cell population, respectively. In each of these cell lines, we readily detected STn+CD133+ sub-populations suggesting that STn is expressed on CD133+ ovarian CSCs. Colony formation assays analyzing FACS-purified STn-CD133-, STn+CD133-, STn-CD133+ and STn+ CD133+ sub-populations suggest that STn expression correlates with anchorage independent growth, a characteristic of cell stemness. Paclitaxel and carboplatin treatment in vitro significantly increased the proportion of STn+ and CD133+ cells, demonstrating the chemoresistant characteristics of these cells. Treatment with the murine α-STn-MMAE ADCs reduced the viability of OvCa cell lines in vitro in a dose-dependent manner. Treatment with murine and humanized α -STn- MMAE antibodies in vivo reduced tumor volumes, whereas vehicle treatment did not impede tumor growth. Interestingly, the unconjugated antibody also had a modest negative impact on tumor volume.

CONCLUSION: A novel, highly specific STn antibody identifies the STn antigen in OvCa cell lines and patient samples. STn+ and CD133+ cells demonstrate stem-like characteristics such as anchorage-independent growth and chemoresistance. STn ADCs decreased cell viability in vitro and reduced tumor volumes in vivo, suggesting that specific therapeutic targeting of STn in ovarian tumors may be an effective clinical strategy to eliminate quiescent CSCs.

Citation Format: B.R. Rueda, K. Starbuck, D. Eavarone, J. Prendergast, J. Stein, R. Foster, J. Behrens. TARGETING A CHEMORESISTANT OVARIAN CANCER CELL POPULATION VIA THE CARBOHYDRATE ANTIGEN SIALYL TN [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr MIP-071.

Intramuscular Ziprasidone Dosing for Acute Agitation in the Pediatric Emergency Department: An Observational Study

BACKGROUND

Intramuscular (IM) ziprasidone is often used to manage acute agitation. Limited data exist on the pediatric dosing of ziprasidone in the emergency department (ED).

OBJECTIVE

To characterize the mg/kg dosing differences between pediatric ED patients who respond to an initial dose of ziprasidone versus patients who do not.

METHODS

This was a retrospective, observational study of 5- to 18-year-old patients who were treated with IM ziprasidone in the pediatric ED from 2007 to 2015. Medical records were reviewed to determine demographic and clinical information. Patients were deemed responders to ziprasidone if they required no additional rescue medication for acute agitation within 30 minutes of the initial dose.

RESULTS

Forty children received 50 doses of IM ziprasidone. Twenty-seven (68%) patients responded to the initial ziprasidone dose, requiring no further medication intervention for their acute agitation. Responders were given a mean initial dose of 0.19 ± 0.1 mg/kg, while nonresponders were given an initial mean dose of 0.13 ± 0.06 mg/kg ( P = .03).

CONCLUSION

A significant dose difference exists between patients who required only one initial dose of ziprasidone compared to those who required additional medication. As a result, an initial dose of 0.2 mg/kg of IM ziprasidone may be considered when managing acutely agitated pediatric patients in the ED.

Reactive arthritis following a Microsporidia infection

Reactive arthritis may be caused by both sexually transmissible and enteric organisms, though Microsporidia is not currently recognised as a causative agent. This case report describes the development of reactive arthritis following Microsporidia infection in an immunocompetent man.

Risk factors associated with incident sexually transmitted infections in HIV-positive patients in the Australian HIV Observational Database: a prospective cohort study

OBJECTIVES

We established a subcohort of HIV-positive individuals from 10 sexual health clinics within the Australian HIV Observational Database (AHOD). The aim of this study was to assess demographic and other factors that might be associated with an incident sexually transmitted infection (STI).

METHODS

The cohort follow-up was from March 2010 to March 2013, and included patients screened at least once for an STI. We used survival methods to determine time to first new and confirmed incident STI infection (chlamydia, gonorrhoea, syphilis or genital warts). Factors evaluated included sex, age, mode of HIV exposure, year of AHOD enrolment, hepatitis B or C coinfection, time-updated CD4 cell count, time-updated HIV RNA viral load, and prior STI diagnosis.

RESULTS

There were 110 first incident STI diagnoses observed over 1015 person-years of follow-up, a crude rate of 10.8 [95% confidence interval (CI) 9.0-13.0] per 100 person-years. Factors independently associated with increased risk of incident STI included younger age [≥ 50 vs. 30-39 years old, adjusted hazards ratio (aHR) 0.4; 95% CI 0.2-0.8; P < 0.0001]; prior STI infection (aHR 2.5; 95% CI 1.6-3.8; P < 0.001), and heterosexual vs. men who have sex with men (MSM) as the likely route of exposure (aHR 0.2; 95% CI 0.1-0.6; P < 0.001).

CONCLUSIONS

In this cohort of individualsbeing treated with antiretroviral drugs, those who were MSM, who were 30-39 years old, and who had a prior history of STI, were at highest risk of a further STI diagnosis.

Reactive arthritis at the Sydney Sexual Health Centre 1992-2012: declining despite increasing chlamydia diagnoses

Reactive arthritis is an under-studied complication of genital Chlamydia trachomatis infection (chlamydia). We assessed trends and risk factors for reactive arthritis in a large urban sexual health clinic. Using a case-control design, data on reactive arthritis cases and controls at the Sydney Sexual Health Centre over the period 1992-2012 were extracted and multivariate analyses were performed. Trend analyses were performed on reactive arthritis diagnoses. Over the 1992-2012 study period, 85 reactive arthritis cases were diagnosed at Sydney Sexual Health Centre. The rate of reactive arthritis diagnoses decreased over time (23 in 1992-1996 to one in 2007-2011 and none in 2012), while chlamydia diagnoses increased (770 in 1992-1996 to 2257 in 2007-2011). In multivariate analysis, factors independently associated with a reactive arthritis diagnosis were: being male (adjusted odds ratio [aOR] 3.27; 95% confidence interval [CI] 1.04-10.32; p = 0.043) or born overseas (aOR 2.69; 95% CI 1.27-5.70; p = 0.010), while a past sexually transmitted infection other than chlamydia or non-gonococcal urethritis was protective (aOR 0.21; 95% CI 0.10-0.45; p < 0.001). Reactive arthritis was not associated with current or recent chlamydia infection (p = 0.184) but was marginally associated with past non-gonococcal urethritis (p = 0.080). This study found a decline in reactive arthritis diagnoses despite an increase in chlamydia diagnoses.

Biofunctionalization of conductive hydrogel coatings to support olfactory ensheathing cells at implantable electrode interfaces

Mechanical discrepancies between conventional platinum (Pt) electrodes and neural tissue often result in scar tissue encapsulation of implanted neural recording and stimulating devices. Olfactory ensheathing cells (OECs) are a supportive glial cell in the olfactory nervous system which can transition through glial scar tissue while supporting the outgrowth of neural processes. It has been proposed that this function can be used to reconnect implanted electrodes with the target neural pathways. Conductive hydrogel (CH) electrode coatings have been proposed as a substrate for supporting OEC survival and proliferation at the device interface. To determine an ideal CH to support OECs, this study explored eight CH variants, with differing biochemical composition, in comparison to a conventional Pt electrodes. All CH variants were based on a biosynthetic hydrogel, consisting of poly(vinyl alcohol) and heparin, through which the conductive polymer (CP) poly(3,4-ethylenedioxythiophene) was electropolymerized. The biochemical composition was varied through incorporation of gelatin and sericin, which were expected to provide cell adherence functionality, supporting attachment, and cell spreading. Combinations of these biomolecules varied from 1 to 3 wt %. The physical, electrical, and biological impact of these molecules on electrode performance was assessed. Cyclic voltammetry and electrochemical impedance spectroscopy demonstrated that the addition of these biological molecules had little significant effect on the coating's ability to safely transfer charge. Cell attachment studies, however, determined that the incorporation of 1 wt % gelatin in the hydrogel was sufficient to significantly increase the attachment of OECs compared to the nonfunctionalized CH.