Unlocking Public Health Data: Navigating New Legal Guardrails and Emerging AI Challenges.

Here, we analyze the public health implications of recent legal developments - including privacy legislation, intergovernmental data exchange, and artificial intelligence governance - with a view toward the future of public health informatics and the potential of diverse data to inform public health actions and drive population health outcomes.

Web-based Telemonitoring of Visual Function and Self-reported Postoperative Outcomes in Cataract Care: an International Multicenter RCT.

PURPOSE: Comparing web-based, self-administered follow-up after cataract surgery to conventional face-to-face follow-up. SETTING: Eye clinics in the Netherlands, Austria and Germany. DESIGN: Randomized controlled trial with an embedded method comparison study [ClinicalTrials.gov: NCT04809402]. METHODS: Routine cataract patients were randomized into two groups: the 'telemonitoring' group undertook web-based vision self-assessments and questionnaires from home, while the 'usual care' group received conventional care. All participants had a 4-6 week post-surgery clinic visit for safety and validation purposes. Outcomes included: the web-test's accuracy for assessing postoperative visual acuity (VA) and refractive error; adverse event rates; and patient reported outcome measurements (PROMs). RESULTS: 94 participants (188 eyes) were enrolled. Web-based uncorrected distance VA testing demonstrated a negligible mean difference (-0.03±0.14 logMAR) when compared to conventional ETDRS chart testing, with 95% limits-of-agreement ranging from -0.30 to 0.24 logMAR. The web-based refraction assessment overestimated the postoperative refractive error (mean difference 0.15±0.67 diopters), resulting in a poorer corrected distance VA compared to subjective refraction (mean 0.1 vs. -0.1 logMAR). Rates of adverse events and unscheduled consultations were minimal across both groups. Preoperative and postoperative PROMs questionnaires had a 100% response rate. Visual functioning (Catquest-9SF and NEI-VFQ-25) improved after surgery (mean improvement -0.80 and 16.70 respectively) and did not significantly differ between the two groups. CONCLUSION: The cataract patients in this study effectively provided postoperative outcome data via a web-interface. Both conventional and web-based follow-ups yielded similar PROMs and adverse event rates. Future developments should reduce the variability in the web-based VA test and yield representative refraction outcomes.

The MuSK-BMP pathway regulates synaptic Nav1.4 localization and muscle excitability.

The neuromuscular junction (NMJ) is the linchpin of nerve-evoked muscle contraction. Broadly considered, the function of the NMJ is to transduce a nerve action potential into a muscle fiber action potential (MFAP). Efficient information transfer requires both cholinergic signaling, responsible for the generation of endplate potentials (EPPs), and excitation, the activation of postsynaptic voltage-gated sodium channels (Nav1.4) to trigger MFAPs. In contrast to the cholinergic apparatus, the signaling pathways that organize Nav1.4 and muscle fiber excitability are poorly characterized. Muscle-specific kinase (MuSK), in addition to its Ig1 domain-dependent role as an agrin-LRP4 receptor, is also a BMP co-receptor that binds BMPs via its Ig3 domain and shapes BMP-induced signaling and transcriptional output. Here we probed the function of the MuSK-BMP pathway at the NMJ using mice lacking the MuSK Ig3 domain ('ΔIg3-MuSK'). Synapses formed normally in ΔIg3-MuSK animals, but the postsynaptic apparatus was fragmented from the first weeks of life. Anatomical denervation was not observed at any age examined. Moreover, spontaneous and nerve-evoked acetylcholine release, AChR density, and endplate currents were comparable to WT. However, trains of nerve-evoked MFAPs in ΔIg3-MuSK muscle were abnormal as revealed by increased jitter and blocking in single fiber electromyography. Further, nerve-evoked compound muscle action potentials (CMAPs), as well as twitch and tetanic muscle torque force production, were also diminished. Finally, Nav1.4 levels were reduced at ΔIg3-MuSK synapses but not at the extrajunctional sarcolemma, indicating that the observed excitability defects are the result of impaired localization of this voltage-gated ion channel at the NMJ. We propose that MuSK plays two distinct roles at the NMJ: as an agrin-LRP4 receptor necessary for establishing and maintaining cholinergic signaling, and as a BMP co-receptor required for maintaining proper Nav1.4 density, nerve-evoked muscle excitability and force production. The MuSK-BMP pathway thus emerges as a target for modulating excitability and functional innervation, which are defective in conditions such as congenital myasthenic syndromes and aging.

Neighborhood disadvantage, household chaos, and personal stressors: exploring early-life contextual factors and current mental health symptoms in college students.

OBJECTIVE: Using Bronfenbrenner's socio-ecological model as a frame, we explored the impact of neighborhood disadvantage, household chaos, and personal stressors on current mental health symptoms in college students. PARTICIPANTS: 144 students at a large, public university in the southern U.S. METHODS: Participants completed measures of demographics, family-of-origin household chaos, stressors, anxiety, and depression, and provided their childhood home ZIP code. Using U.S. Census Data, four structural indicators of neighborhood disadvantage were extracted and appended to each participant's ZIP code. RESULTS: Hierarchical regression revealed that all three variables predicted anxiety symptoms. However, only household chaos and personal stressors predicted current depressive symptoms. Unexpectedly, greater neighborhood disadvantage predicted lower levels of current anxiety. Mediation analyses demonstrated that personal stressors partially mediated the relationships between household chaos and mental health symptoms. CONCLUSIONS: College administration and counseling centers may wish to consider pre-college factors that influence college students' current anxious and depressive symptoms.

Mental health services for all: Factors influencing desire for mental health services among underresourced adults during COVID-19.

The coronavirus disease (COVID-19) pandemic has substantially impacted psychological health in the U.S and has disproportionately impacted underresourced individuals. Despite the higher need for mental health services during this time, service availability and access were disrupted due to increased demand, social distancing recommendations, and stay-at-home orders. Thus, it is crucial to understand factors that predict the desire for psychological services for underresourced individuals. The present study examined factors at multiple levels of Bronfenbrenner's socioecological model (Bronfenbrenner, 1994) to determine which factors best predicted the desire for mental health services including individual, group, in-person, and online services. The sample consisted of 155 underresourced adults in North Carolina. Participants completed an online survey of mental health symptoms, coping strategies, COVID-19 related stressors, and provided demographic information including ZIP code, which was used to classify urban-central and urban-outlying dwellers. Results from univariate general linear models demonstrated that depression symptoms, venting as a coping strategy, COVID-related stress, and living in more rural regions were all significant predictors of the desire for psychological services. Venting as a predictor of the desire for services may signify a general misunderstanding regarding the purpose of psychotherapy as well as the need for individuals to gain social support and connectedness during a pandemic. This study helps to clarify individual-level and contextual factors that impact the desire for psychological services during a global pandemic. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Readiness to Change: A Pathway to the Adoption of Trauma-Sensitive Teaching.

Creating a trauma-sensitive classroom requires a shift in perspective from viewing a student's problematic behavior as a function of poor character to considering it contextually. However, a trauma-sensitive perspective may be insufficient for school staff to implement trauma-sensitive practices. Theoretically, motivation, or readiness to change (R2C), is needed to adopt any new behavior. Therefore, the purpose of this study was to examine the role of R2C in the relation between attitudes related to trauma-informed care (ARTIC) and the adoption of trauma-sensitive practices in a school setting. The targeted elementary school primarily serves Black students (83%), living below the federal poverty line. All staff attended an in-service training about trauma-sensitive schools (TSS), in which trauma-sensitive strategies were modeled, and student-friendly, emotional regulation materials were provided. Teachers and staff (n = 40) were assessed one year after receiving the TSS training. Participants reported their ARTIC, R2C, and trauma-informed strategy adoption. Using PROCESS Model 4, R2C fully mediated the relation between ARTIC and reported use of specific trauma-sensitive classroom strategies (ß = 0.19, bootstrapped SE = 0.12, 95% LLCI = 0.04, 95% ULCI = 0.49). Facilitating R2C is essential when implementing trauma-sensitive school strategies. System-wide policies that may help promote the uptake of trauma-sensitive practices are described.

Analysis of the Performance of Narrow-Bandgap Organic Solar Cells Based on a Diketopyrrolopyrrole Polymer and a Nonfullerene Acceptor.

The combination of narrow-bandgap diketopyrrolopyrrole (DPP) polymers and nonfullerene acceptors (NFAs) seems well-matched for solar cells that exclusively absorb in the near infrared but they rarely provide high efficiency. One reason is that processing of the active layer is complicated by the fact that DPP-based polymers are generally only sufficiently soluble in chloroform (CF), while NFAs are preferably processed from halogenated aromatic solvents. By using a ternary solvent system consisting of CF, 1,8-diiodooctane (DIO), and chlorobenzene (CB), the short-circuit current density is increased by 50% in solar cells based on a DPP polymer (PDPP5T) and a NFA (IEICO-4F) compared to the use of CF with DIO only. However, the open-circuit voltage and fill factor are reduced. As a result, the efficiency improves from 3.4 to 4.8% only. The use of CB results in stronger aggregation of IEICO-4F as inferred from two-dimensional grazing-incidence wide-angle X-ray diffraction. Photo- and electroluminescence and mobility measurements indicate that the changes in performance can be ascribed to a more aggregated blend film in which charge generation is increased but nonradiative recombination is enhanced because of reduced hole mobility. Hence, while CB is essential to obtain well-ordered domains of IEICO-4F in blends with PDPP5T, the morphology and resulting hole mobility of PDPP5T domains remain suboptimal. The results identify the challenges in processing organic solar cells based on DPP polymers and NFAs as near-infrared absorbing photoactive layers.

Social Support and Suicidal Ideation Among Prisoners with Major Depressive Disorder.

This study explored the impact of social support on suicidal ideation in 169 prisoners with major depressive disorder, accounting for known demographic, criminological, and clinical risk factors. Greater social support was associated with a lower likelihood of the presence of current suicide ideation. This effect remained significant even after adjusting for other significant predictors of suicide ideation including sex, length of sentence served, severity of current depression, and having prior suicide attempts. This study is the first to explore social support and other known risk factors for suicide ideation in a prison population with major depressive disorder. Our findings demonstrate that, even in the presence of significant risk factors for suicidal ideation, social support remained a strong predictor, suggesting the importance of fostering social support in correctional settings.

An open and closed case: timing of closure following laparostomy.

INTRODUCTION: Laparostomy is important in the management of patients with intra-abdominal gastrointestinal catastrophe or trauma. It carries significant risk and is resource intensive, both in terms of nursing and surgically. The main goal is to achieve prompt myofascial closure (MFC) in order to minimise morbidity and mortality. Early MFC was initially defined as within 2-3 weeks but there is growing evidence that this should be measured in days. METHODS: Retrospective analysis was undertaken of laparostomy cases between 2016 and 2018 at an acute trust and trauma centre serving a population of 500,000. Indication, duration of open abdomen (OA), number of relook procedures and consultant presence were examined to see whether they affected MFC rates, morbidity and mortality. RESULTS: Overall, 76 laparostomies were performed during the 3-year study period. The most common indication was peritonitis (68.4%). As duration of OA and number of relook procedures increased, the chances of MFC fell significantly. After day 1, MFC rates fell by 20% with each subsequent 24 hours. Leaving the abdomen open primarily at index procedure compared with performing laparostomy following a postoperative complication was associated with significantly higher MFC rates (92.6% vs 68.2%, (p=0.006). The mortality rate was 15.8%. CONCLUSIONS: If the OA is not closed within five days or by the third relook procedure, then achieving MFC is unlikely. Alternative methods should be employed to close the abdomen rather than continuing to take the patient back to theatre for relook laparotomies while increasing the risk of morbidity and mortality. A proactive strategy to forming primary laparostomy at the index procedure has high closure rates.

Efficient Thick-Film Polymer Solar Cells with Enhanced Fill Factors via Increased Fullerene Loading.

Developing effective methods to make efficient bulk-heterojunction polymer solar cells at roll-to-roll relevant active layer thickness is of significant importance. We investigate the effect of fullerene content in polymer:fullerene blends on the fill factor (FF) and on the performance of thick-film solar cells for four different donor polymers PTB7-Th, PDPP-TPT, BDT-FBT-2T, and poly[5,5'-bis(2-butyloctyl)-(2,2'-bithiophene)-4,4'-dicarboxylate- alt-5,5'-2,2'-bithiophene] (PDCBT). At a few hundreds of nanometers thickness, increased FFs are observed in all cases and improved overall device performances are obtained except for PDCBT upon increasing fullerene content in blend films. This fullerene content effect was studied in more detail by electrical and morphological characterization. The results suggest enhanced electron mobility and suppressed bimolecular recombination upon increasing fullerene content in thick polymer:fullerene blend films, which are the result of larger fullerene aggregates and improved interconnectivity of the fullerene phases that provide continuous percolating pathways for electron transport in thick films. These findings are important because an effective and straightforward method that enables fabricating efficient thick-film polymer solar cells is desirable for large-scale manufacturing via roll-to-roll processing and for multijunction devices.

The influence of siloxane side-chains on the photovoltaic performance of a conjugated polymer.

The effect of gradually replacing the branched alkyl side chains of a diketopyrrolopyrrole (DPP) conjugated polymer by linear side chains containing branched siloxane end groups on the photovoltaic performance of blends of these polymers with a common fullerene acceptor is investigated. With an increasing proportion of siloxane side chains, the molecular weight and solubility of the polymers decreases. While the siloxane containing polymers exhibit a higher hole mobility in field-effect transistors, their performance in solar cells is less than the polymer with only alkyl sides chains. Using grazing-incidence wide-angle X-ray scattering, transmission electron microscopy, and fluorescence spectroscopy we identify two main reasons for the reduced performance of siloxane containing polymers in solar cells. The first one is a somewhat coarser phase-separated morphology with slightly wider polymer fibers. This is unexpected as often the fiber width is inversely correlated with polymer solubility. The second one is stronger non-radiative decay of the pristine polymers containing siloxane side chains.

Intraspecific variation in soy across the leaf economics spectrum.

Background and Aims: Intraspecific trait variation (ITV) is an important dimension of plant ecological diversity, particularly in agroecosystems, where phenotypic ITV (within crop genotypes) is an important correlate of key agroecosystem processes including yield. There are few studies that have evaluated whether plants of the same genotype vary along well-defined axes of biological variation, such as the leaf economics spectrum (LES). There is even less information disentangling environmental and ontogenetic determinants of crop ITV along an intraspecific LES, and whether or not a plant's position along an intraspecific LES is correlated with reproductive output. Methods: We sought to capture the extent of phenotypic ITV within a single cultivar of soy (Glycine max) - the world's most commonly cultivated legume - using a data set of nine leaf traits measured on 402 leaves, sampled from 134 plants in both agroforestry and monoculture management systems, across three distinct whole-plant ontogenetic stages (while holding leaf age and canopy position stable). Key Results: Leaf traits covaried strongly along an intraspecific LES, in patterns that were largely statistically indistinguishable from the 'universal LES' observed across non-domesticated plants. Whole-plant ontogenetic stage explained the highest proportion of phenotypic ITV in LES traits, with plants progressively expressing more 'resource-conservative' LES syndromes throughout development. Within ontogenetic stages, leaf traits differed systematically across management systems, with plants growing in monoculture expressing more 'resource-conservative' trait syndromes: trends largely owing to an approximately ≥50% increases in leaf mass per area (LMA) in high-light monoculture vs. shaded agroforestry systems. Certain traits, particularly LMA, leaf area and maximum photosynthetic rates, correlated closely with plant-level reproductive output. Conclusions: Phenotypic ITV in soy is governed by constraints in trait trade-offs along an intraspecific LES, which in turn (1) underpins plant responses to managed environmental gradients, and (2) reflects shifts in plant functional biology and resource allocation that occur throughout whole-plant ontogeny.

Focused electrical stimulation using a single current source.

OBJECTIVE: Cochlear implants, while providing significant benefits to recipients, remain limited due to broad neural activation. Focussed multipolar stimulation (FMP) is an advanced stimulation strategy that uses multiple current sources to produce highly focussed patterns of neural excitation in order to overcome these shortcomings. APPROACH: This report presents single-source multipolar stimulation (SSMPS), a novel form of stimulation based on a single current source and a passive current divider. Compared to conventional FMP with multiple current sources, SSMPS can be implemented as a modular addition to conventional (i.e. single) current source stimulation systems facilitating charge balance within the cochlea. As with FMP, SSMPS requires the determination of a transimpedance matrix to allow for focusing of the stimulation. The first part of this study therefore investigated the effects of varying the probe stimulus (e.g. current level and pulse width) on the measurement of the transimpedance matrix. SSMPS was then studied using in vitro based measurements of voltages at non-stimulated electrodes along an electrode array in normal saline. The voltage reduction with reference to monopolar stimulation was compared to tripolar and common ground stimulation, two clinically established stimulation modes. Finally, a proof of principle in vivo test of SSMPS in a feline model was performed. MAIN RESULTS: A probe stimulus of at least 40 nC is required to reliably measure the transimpedance matrix. In vitro stimulation using SSMPS resulted in a significantly greater voltage reduction compared to monopolar, tripolar and common ground stimulation. Interestingly, matching measurement and stimulation parameters did not lead to an improved focussing performance. Compared to monopolar stimulation, SSMPS resulted in reduced spread of neural activity in the inferior colliculus, albeit with increased thresholds. SIGNIFICANCE: The present study demonstrates that SSMPS successfully limits the broadening of the excitatory field along the electrode array and a subsequent reduction in the spread of neural excitation.

Subnaphthalocyanines as Electron Acceptors in Polymer Solar Cells: Improving Device Performance by Modifying Peripheral and Axial Substituents.

A new class of subnaphthalocyanines bearing various peripheral and axial substituents have been synthesized for use as electron acceptors in solution-processed bulk-heterojunction polymer solar cells. The resulting solar cells exhibit modest photovoltaic performance with contributions from both the polymer donor and subnaphthalocyanine acceptor to the photocurrent.

"Double-Cable" Conjugated Polymers with Linear Backbone toward High Quantum Efficiencies in Single-Component Polymer Solar Cells.

A series of "double-cable" conjugated polymers were developed for application in efficient single-component polymer solar cells, in which high quantum efficiencies could be achieved due to the optimized nanophase separation between donor and acceptor parts. The new double-cable polymers contain electron-donating poly(benzodithiophene) (BDT) as linear conjugated backbone for hole transport and pendant electron-deficient perylene bisimide (PBI) units for electron transport, connected via a dodecyl linker. Sulfur and fluorine substituents were introduced to tune the energy levels and crystallinity of the conjugated polymers. The double-cable polymers adopt a "face-on" orientation in which the conjugated BDT backbone and the pendant PBI units have a preferential π-π stacking direction perpendicular to the substrate, favorable for interchain charge transport normal to the plane. The linear conjugated backbone acts as a scaffold for the crystallization of the PBI groups, to provide a double-cable nanophase separation of donor and acceptor phases. The optimized nanophase separation enables efficient exciton dissociation as well as charge transport as evidenced from the high-up to 80%-internal quantum efficiency for photon-to-electron conversion. In single-component organic solar cells, the double-cable polymers provide power conversion efficiency up to 4.18%. This is one of the highest performances in single-component organic solar cells. The nanophase-separated design can likely be used to achieve high-performance single-component organic solar cells.

Aqueous Nanoparticle Polymer Solar Cells: Effects of Surfactant Concentration and Processing on Device Performance.

Polymer solar cells based on PDPP5T and PCBM as donor and acceptor materials, respectively, were processed from aqueous nanoparticle dispersions. Careful monitoring and optimization of the concentration of free and surface-bound surfactants in the dispersion, by measuring the conductivity and ζ-potential, is essential to avoid aggregation of nanoparticles at low concentration and dewetting of the film at high concentration. The surfactant concentration is crucial for creating reproducible processing conditions that aid in further developing aqueous nanoparticle processed solar cells. In addition, the effects of adding ethanol, of aging the dispersion, and of replacing [60]PCBM with [70]PCBM to enhance light absorption were studied. The highest power conversion efficiencies (PCEs) obtained are 2.0% for [60]PCBM and 2.4% for [70]PCBM-based devices. These PCEs are limited by bimolecular recombination of photogenerated charges. Cryo-TEM reveals that the two components phase separate in the nanoparticles, forming a PCBM-rich core and a PDPP5T-rich shell and causing a nonoptimal film morphology.

Gentamicin Applied to the Oval Window Suppresses Vestibular Function in Guinea Pigs.

Intratympanic gentamicin therapy is widely used clinically to treat the debilitating symptoms of Ménière's disease. Cochleotoxicity is an undesirable potential side effect of the treatment and the risk of hearing loss increases proportionately with gentamicin concentration in the cochlea. It has recently been shown that gentamicin is readily absorbed through the oval window in guinea pigs. The present study uses quantitative functional measures of vestibular and cochlea function to investigate the efficacy of treating the vestibule by applying a small volume of gentamicin onto the stapes footplate in guinea pigs. Vestibular and cochlea function were assessed by recording short latency vestibular evoked potentials in response to linear head acceleration and changes in hearing threshold, respectively, 1 and 2 weeks following treatment. Histopathology was analyzed in the crista ampullaris of the posterior semi-circular canal and utricular macula in the vestibule, and in the basal and second turns of the cochlea. In animals receiving gentamicin on the stapes footplate, vestibular responses were significantly suppressed by 72.7 % 2 weeks after treatment with no significant loss of hearing. This suggests that the vestibule can be treated directly by applying gentamicin onto the stapes footplate.

The Role of the Axial Substituent in Subphthalocyanine Acceptors for Bulk-Heterojunction Solar Cells.

Four hexachlorosubphthalocyanines SubPcCl6 -X bearing different axial substituents (X) have been synthesized for use as novel electron acceptors in solution-processed bulk-heterojunction organic solar cells. Subphthalocyanines are aromatic chromophoric molecules with cone-shaped structure, good solution processability, intense optical absorption in the visible spectral region, appropriate electron mobilities, and tunable energy levels. Solar cells with subphthalocyanines as the electron acceptor and PTB7-Th as the electron donor exhibit a power conversion efficiency up to 4 % and an external quantum efficiency approaching 60 % due to significant contributions from both the electron donor and the electron acceptor to the photocurrent, indicating a promising prospect of non-fullerene acceptors based on subphthalocyanines and structurally related systems.

A novel role of bone morphogenetic protein-7 in the regulation of adhesion and migration of human monocytic cells.

BACKGROUND: Bone morphogenetic protein (BMP) 7 is abundant in atherosclerotic plaques and increases monocyte pro-coagulant activity by enhancing tissue factor (TF) expression. While several members of the BMP superfamily are able to serve as chemotactic agents for monocytes, the role of BMP-7 in regulation of monocyte motility is not known. AIMS: To assess the effect of BMP-7 on adhesive and migratory properties of human monocytes. METHODS: Chemokinesis, adhesion, and transendothelial migration of BMP-7-treated THP-1 cells and human monocytes were analysed using live-cell imaging, orbital shear, and Boyden chamber assays. Surface presentation of ß2 integrins and phosphorylation status of Akt & focal adhesion kinase (FAK) were studied by flow cytometry and Western blot. RESULTS: High levels of BMP-7 protein were detectable in intimal regions of atherosclerotic plaques; BMP-7 significantly enhanced THP-1 and monocyte chemokinetic properties in vitro (1.21+0.01 and 1.76+0.21 fold increase in crawling distance, respectively). Under orbital shear, adhesion of monocytic cells to microvascular endothelial cell (MVEC) monolayers was also significantly increased by BMP-7 (3.89+1.56 and 2.57+0.97 fold over vehicle). Moreover, BMP-7 accelerated transendothelial migration of THP-1 cells and monocytes towards MCP-1 (5.91+0.88 and 2.96±0.65 fold increase, respectively). BMP-7 enhanced cell surface presentation of ß2 integrins in the active conformation. Observed effects were determined to be Akt and FAK dependent, as shown by pharmacological inhibition. CONCLUSION: BMP-7 directly upregulates adhesion and migration of human monocytic cells via activation of ß2 integrins, Akt, and FAK. Our findings suggest that BMP-7 may serve as a novel contributor to atherogenesis.

Extended interval dosing of natalizumab in multiple sclerosis.

BACKGROUND: Natalizumab (NTZ), a monoclonal antibody to human α4ß1/ß7 integrin, is an effective therapy for multiple sclerosis (MS), albeit associated with progressive multifocal leukoencephalopathy (PML). Clinicians have been extending the dose of infusions with a hypothesis of reducing PML risk. The aim of the study is to evaluate the clinical consequences of reducing NTZ frequency of infusion up to 8 weeks 5 days. METHODS: A retrospective chart review in 9 MS centres was performed in order to identify patients treated with extended interval dosing (EID) regimens of NTZ. Patients were stratified into 3 groups based on EID NTZ treatment schedule in individual centres: early extended dosing (EED; n=249) every 4 weeks 3 days to 6 weeks 6 days; late extended dosing (LED; n=274) every 7 weeks to 8 weeks 5 days; variable extended dosing (n=382) alternating between EED and LED. These groups were compared with patients on standard interval dosing (SID; n=1093) every 4 weeks. RESULTS: 17% of patients on SID had new T2 lesions compared with 14% in EID (p=0.02); 7% of patients had enhancing T1 lesions in SID compared with 9% in EID (p=0.08); annualised relapse rate was 0.14 in the SID group, and 0.09 in the EID group. No evidence of clinical or radiographic disease activity was observed in 62% of SID and 61% of EID patients (p=0.83). No cases of PML were observed in EID group compared with 4 cases in SID cohort. CONCLUSIONS: Dosing intervals up to 8 weeks 5 days did not diminish effectiveness of NTZ therapy. Further monitoring is ongoing to evaluate if the risk of PML is reduced in patients on EID.