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Niloufar Zarghami,1 Alexandre A Khrapitchev,1 Francisco Perez-Balderas,1 Manuel Sarmiento Soto,1 James R Larkin,1 Luca Bau,2 Nicola R Sibson1 1Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK; 2Institute of Biomedical Engineering, Department of Engineering Sciences, University of Oxford, Oxford, UK Background: Molecular MRI is an evolving field of research with strong translational potential. Selection of the appropriate MRI sequence, field strength and contrast agent depend largely on the application. The primary aims of the current study were to: 1) assess the sensitivity of different MRI sequences for detection of iron oxide particles in mouse brain; 2) determine the effect of magnetic field strength on detection of iron oxide particles in vivo; and 3) compare the sensitivity of targeted microparticles of iron oxide (MPIO) or ultra-small superparamagnetic iron oxide (USPIO) for detection of vascular cell adhesion molecule-1 (VCAM-1) in vivo. Methods: Mice were injected intrastriatally with interleukin 1β to induce VCAM-1 expression on the cerebral vasculature. Subsequently, animals were injected intravenously with either VCAM-MPIO or VCAM-USPIO and imaged 1 or 13 hours post-injection, respectively. MRI was performed at 4.7, 7.0, or 9.4 T, using three different T2*-weighted sequences: single gradient echo 3D (GE3D), multi-gradient echo 3D (MGE3D) and balanced steady-state free precession 3D (bSSFP3D). Results: MGE3D yielded the highest signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) for the detection of iron oxide particles. All sequences showed a significant increase in SNR and CNR from 4.7 to 7.0 T, but no further improvement at 9.4 T. However, whilst targeted MPIO enabled sensitive detection of VCAM-1 expression on the cerebral vasculature, the long half-life (16.5 h vs 1.2 min) and lower relaxivity per particle (1.29×10–14 vs 1.18×10–9 Hz L/particle) of USPIO vs. MPIO rendered them impractical for molecular MRI. Conclusion: These findings demonstrate clear advantages of MPIO compared to USPIO for molecularly-targeted MRI, and indicate that the MGE3D sequence is optimal for MPIO detection. Moreover, higher field strengths (7.0/9.4 T) showed enhanced sensitivity over lower field strengths (4.7 T). With the development of biodegradable MPIO, these agents hold promise for clinical translation. Keywords: molecular imaging, preclinical MRI, VCAM-MPIO, VCAM-USPIO, multi gradient echo, bSSFP

Rachel Myers,1 Megan Grundy,2 Cliff Rowe,1 Christian M Coviello,1 Luca Bau,2 Philippe Erbs,3 Johann Foloppe,3 Jean-Marc Balloul,3 Colin Story,1 Constantin C Coussios,2 Robert Carlisle2 1OxSonics Ltd, The Magdalen Centre, 2BUBBL, IBME, Department of Engineering Science, University of Oxford, Oxford, UK; 3Transgene SA, Illkirch-Graffenstaden, France Abstract: The treatment of cancer using nanomedicines is limited by the poor penetration of these potentially powerful agents into and throughout solid tumors. Externally controlled mechanical stimuli, such as the generation of cavitation-induced microstreaming using ultrasound (US), can provide a means of improving nanomedicine delivery. Notably, it has been demonstrated that by focusing, monitoring and controlling the US exposure, delivery can be achieved without damage to surrounding tissue or vasculature. However, there is a risk that such stimuli may disrupt the structure and thereby diminish the activity of the delivered drugs, especially complex antibody and viral-based nanomedicines. In this study, we characterize the impact of cavitation on four different agents, doxorubicin (Dox), cetuximab, adenovirus (Ad) and vaccinia virus (VV), representing a scale of sophistication from a simple small-molecule drug to complex biological agents. To achieve tight regulation of the level and duration of cavitation exposure, a “cavitation test rig” was designed and built. The activity of each agent was assessed with and without exposure to a defined cavitation regime which has previously been shown to provide effective and safe delivery of agents to tumors in preclinical studies. The fluorescence profile of Dox remained unchanged after exposure to cavitation, and the efficacy of this drug in killing a cancer cell line remained the same. Similarly, the ability of cetuximab to bind its epidermal growth factor receptor target was not diminished following exposure to cavitation. The encoding of the reporter gene luciferase within the Ad and VV constructs tested here allowed the infectivity of these viruses to be easily quantified. Exposure to cavitation did not impact on the activity of either virus. These data provide compelling evidence that the US parameters used to safely and successfully delivery nanomedicines to tumors in preclinical models do not detrimentally impact on the structure or activity of these nanomedicines. Keywords: nanomedicine, antibody, virus, ultrasound, cavitation

This paper presents a detailed study on the structural, magnetic, and critical behavior and magnetocaloric effect of LaSrMnCuO prepared by solid-state reaction method. X-ray diffraction patterns indicate that Cu-doped manganite crystallizes to a single phase with a rhombohedral structure. Critical components β, γ, and δ were determined by using modified Arrott plot, Kouvel-Fisher method, and critical isotherm analyses. These components are consistent with their corresponding values and were validated by Widom scaling law and scaling theory. The deduced critical exponents ( β = 0.456, γ = 0.9912, and δ = 3.206) are also close to their corresponding theoretical values predicted by mean-field model, indicating that long-range interaction dominates the critical behavior of the LSMCO system. Spontaneous magnetization was determined by two methods. One method is based on magnetic entropy change under different magnetic fields, and the other method is based on classical extrapolation from the Arrott plot. The two methods are in excellent agreement, confirming the validity of the deduction of spontaneous magnetization using the magnetic entropy change. [ABSTRACT FROM AUTHOR]

We have investigated the structure, magnetic, and electrical properties, and the resistance switching effect (RSE) of La2NiO $_{{ {4+\delta }}} compounds with different excess oxygen levels of \delta = 0.004 - 0.031 . Our results showed the structure changes from tetragonal I4/mmm to orthorhombic Fmmm when reducing \delta value from 0.011 to 0.006. The M(H) curves measured at several temperatures exhibit a coexistence of the weak ferromagnetic and antiferromagnetic interactions. Two shoulders on M(T) curves related to the spin and charge ordering have also been observed. These ordering temperatures depend strongly on \delta ) and low ( RL ) values. The resistance change ratio of the samples defined as 100% \times [RH - RL]/RL is found to be about 18%–57%, which depends on the value of $\delta $ in the samples. [ABSTRACT FROM AUTHOR]

In this study, we report the electric transport of La 0.7Ca 0.3MnO 3 prepared by various methods. Based on the fact that the metallic ferromagnetic and insulating paramagnetic clusters simultaneously exist at transition temperature, we applied phase-coexistence transport model to calculate the temperature dependence of the resistivity. This model can explain quantitatively the electrical conductivity of La 0.7Ca 0.3MnO 3 for the whole temperature range studied. [ABSTRACT FROM AUTHOR]

Objective: Perfluorocarbon nanodroplets (NDs) have been widely investigated as both diagnostic and therapeutic agents. There remains, however, a challenge in generating NDs that do not vaporize spontaneously but can be activated at ultrasound pressures that do not produce unwanted bioeffects. In previous work, it has been shown that phospholipid-coated perfluorobutane (PFB) NDs can potentially overcome this challenge. The aim of this study was to investigate whether these NDs can promote drug delivery., Methods: A combination of high-speed optical imaging and passive cavitation detection was used to study the acoustic properties of the PFB-NDs in a tissue mimicking phantom. PFB-NDs were exposed to ultrasound at frequencies from 0.5 to 1.5 MHz and peak negative pressures from 0.5 to 3.5 MPa. In addition, the penetration depth of two model drugs (Nile Red and 200 nm diameter fluorescent polymer spheres) into the phantom was measured., Results: PFB NDs were found to be stable in aqueous suspension at both 4°C and 37°C; their size remaining unchanged at 215 ± 11 nm over 24 h. Penetration of both model drugs in the phantom was found to increase with increasing ultrasound peak negative pressure and decreasing frequency and was found to be positively correlated with the energy of acoustic emissions. Extravasation depths >1 mm were observed at 0.5 MHz with pressures <1 MPa., Conclusion: The results of the study thus suggest that PFB NDs can be used both as drug carriers and as nuclei for cavitation to enhance drug delivery without the need for high intensity ultrasound., Competing Interests: Conflict of interest The authors declare no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study is to demonstrate 3-dimensional (3D) acoustic wave sparsely activated localization microscopy (AWSALM) of microvascular flow in vivo using phase change contrast agents (PCCAs)., Materials and Methods: Three-dimensional AWSALM using acoustically activable PCCAs was evaluated on a crossed tube microflow phantom, the kidney of New Zealand White rabbits, and the brain of C57BL/6J mice through intact skull. A mixture of C 3 F 8 and C 4 F 10 low-boiling-point fluorocarbon gas was used to generate PCCAs with an appropriate activation pressure. A multiplexed 8-MHz matrix array connected to a 256-channel ultrasound research platform was used for transmitting activation and imaging ultrasound pulses and recording echoes. The in vitro and in vivo echo data were subsequently beamformed and processed using a set of customized algorithms for generating 3D super-resolution ultrasound images through localizing and tracking activated contrast agents., Results: With 3D AWSALM, the acoustic activation of PCCAs can be controlled both spatially and temporally, enabling contrast on demand and capable of revealing 3D microvascular connectivity. The spatial resolution of the 3D AWSALM images measured using Fourier shell correlation is 64 μm, presenting a 9-time improvement compared with the point spread function and 1.5 times compared with half the wavelength. Compared with the microbubble-based approach, more signals were localized in the microvasculature at similar concentrations while retaining sparsity and longer tracks in larger vessels. Transcranial imaging was demonstrated as a proof of principle of PCCA activation in the mouse brain with 3D AWSALM., Conclusions: Three-dimensional AWSALM generates volumetric ultrasound super-resolution microvascular images in vivo with spatiotemporal selectivity and enhanced microvascular penetration., Competing Interests: Conflicts of interest and sources of funding: This work was funded in part by the Engineering and Physical Sciences Research Council (EPSRC) under grant EP/T008970/1, EP/T008067/1, and EP/N026942/1; the EPSRC Impact Acceleration Account under grant EP/R511547/1; the National Institute for Health Research i4i under grant NIHR200972; and the British Heart Foundation under grant PG/18/48/33832. The authors report no conflicts of interest., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background and Objectives: Serum biomarkers are emerging as useful prognostic tools for multiple sclerosis (MS); however, long-term studies are lacking. We aimed to evaluate the long-term prognostic value of the serum levels of neurofilament light chain (NfL), total tau, glial fibrillary acidic protein (GFAP), and chitinase 3-like-1 (CHI3L1) measured close to the time of MS onset., Methods: In this retrospective, exploratory, observational, case and controls study, patients with relapsing-remitting MS (RRMS) with available baseline serum samples and prospectively follow-up in our MS unit for a long time were selected based on their clinical evolution to form two groups: (1) a benign RRMS (bRRMS) group, defined as patients with an Expanded Disability Status Scale (EDSS) score of ≤ 3 at ≥ 10 years of follow-up; (2) an aggressive RRMS (aRRMS) group, defined as patients with an EDSS score of ≥ 6 at ≤ 15 years of follow-up. An age-matched healthy control (HC) group was selected. NfL, total tau, and GFAP serum levels were quantified using a single-molecule array (SIMOA), and CHI3L1 was quantified using ELISA., Results: Thirty-one patients with bRRMS, 19 with aRRMS, and 10 HC were included. The median follow-up time from sample collection was 17.74 years (interquartile range, 14.60-20.37). Bivariate and multivariate analyses revealed significantly higher NfL and GFAP levels in the aRRMS group than in the bRRMS group. A receiver operating characteristic curve analysis identified serum NfL level as the most efficient marker for distinguishing aRRMS from bRRMS., Discussion: This proof-of-concept study comparing benign and aggressive RRMS groups reinforces the potential role of baseline NfL serum levels as a promising long-term disability prognostic marker. In contrast, serum GFAP, total tau, and CHI3L1 levels demonstrated a lower or no ability to differentiate between the long-term outcomes of RRMS., (© 2023. The Author(s).)

Introduction: The role of the kappa-free light chain (kFLC) in the diagnosis of multiple sclerosis (MS) and, to a lesser extent, its role as a medium-term prognostic marker have been extensively studied. This study aimed to explore its potential as a long-term prognostic marker for MS., Methods: We performed an exploratory retrospective observational study by selecting patients systemically followed up in our MS unit with available cerebrospinal fluid and serum samples at the time of initial evaluation. Two groups were defined: benign MS (bMS), defined as patients with Expanded Disability Status Scale (EDSS) ≤ 3 at 10 years of follow-up, and aggressive MS (aMS), defined as patients with EDSS ≥ 6 at 15 years of follow-up. Clinical variables were collected, and the immunoglobulin G (IgG) index, kFLC index, and oligoclonal bands (OCB) were determined for all patients and compared between the groups., Results: Twenty bMS and 15 aMS patients were included in this study. Sixty percent (21/35) were female, and the mean age at the time of the first symptom was 31.5 ± 9.45 years, with no statistical differences between groups. Median follow-up time was 19.8 years (Interquartile range, IQR 15.9-24.6). The median EDSS scores at the last follow-up were 1.5 and 7.5 in the bMS and the aMS group, respectively. No statistically significant differences were found in the kFLC index between the two groups (136.6 vs. 140.27, p=0.59). The IgG index was positive in 62.9% of patients (55% bMS vs. 73.3% aMS, p>0.05), and OCB was positive in 88.6% (90% bMS vs. 86.7% aMS, p>0.05). A significant positive correlation was found between IgG and kFLC indices (r s = 0.85, p<0.001)., Conclusion: Given the absence of differences between the two groups with opposite disease courses, it is unlikely that the kFLC index is a reliable and powerful marker of long-term prognosis in MS., Competing Interests: PA-P, LB, EM, IL, AM-V, LR-P, AM-Y and SM-Y received honoraria for participating on advisory boards and for collaborations as consultants and scientific communications; they also received research support as well as funding for travel and congress expenses from Roche, Biogen Idec, Novartis, TEVA, Merck, Genzyme, Sanofi, Bayer, Almirall, and Celgene. LG-S and VM received funding for travel and congress expenses from The Binding Site. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Arroyo-Pereiro, García-Serrano, Morandeira, Urban, Mas, Framil, León, Muñoz-Vendrell, Matas, Romero-Pinel, Martínez-Yélamos, Martínez-Yélamos and Bau.)

Background: Natalizumab (NTZ) and ocrelizumab (OCR) can be used for the treatment of relapsing-remitting multiple sclerosis (RRMS). In patients treated with NTZ, screening for JC virus (JCV) is mandatory, and a positive serology usually requires a change in treatment after 2 years. In this study, JCV serology was used as a natural experiment to pseudo-randomize patients into NTZ continuation or OCR., Methods: An observational analysis of patients who had received NTZ for at least 2 years and were either changed to OCR or maintained on NTZ, depending on JCV serology status, was performed. A stratification moment (STRm) was established when patients were pseudo-randomized to either arm (NTZ continuation if JCV negativity, or change to OCR if JCV positivity). Primary endpoints include time to first relapse and presence of relapses after STRm and OCR initiation. Secondary endpoints include clinical and radiological outcomes after 1 year., Results: Of the 67 patients included, 40 continued on NTZ (60%) and 27 were changed to OCR (40%). Baseline characteristics were similar. Time to first relapse was not significantly different. Ten patients in the JCV + OCR arm presented a relapse after STRm (37%), four during the washout period, and 13 patients in the JCV-NTZ arm (32.5%, p = 0.701). No differences in secondary endpoints were detected in the first year after STRm., Conclusions: The JCV status can be used as a natural experiment to compare treatment arms with a low selection bias. In our study, switching to OCR versus NTZ continuation led to similar disease activity outcomes., (© 2023. The Author(s).)

Introduction: Prior studies have suggested that cardiovascular risk factors (CVRFs) can affect the prognosis of multiple sclerosis (MS). The aim of this study was to assess if CVRFs affect the early course of MS., Methods: A retrospective observational study was performed, including patients diagnosed with relapsing-remitting MS (RRMS) from 2010 to 2020, with at least 2 years of disease and 6 months follow-up. Age at onset, disease duration, number of relapses, time to confirmed Expanded Disability Status Scale (EDSS) 3.0 and 6.0, and time to secondary progressive MS (SPMS) were collected. Presence and date at onset of hypertension (HT), diabetes mellitus (DM), high low-density lipoprotein cholesterol (LDLc), and smoking during the study period were collected. The primary objective was to assess if CVRFs at the onset of MS are associated with lower time to EDSS 3.0, time to EDSS 6.0, and time to SPMS, using bivariate and multivariate analysis., Results: 281 RRMS patients were included; median age at onset was 33 (IQR 26-39); 69.4% were female. Median EDSS at onset was 1.5 (IQR 1-2.5). Nine patients reached SPMS; 24 patients were diagnosed with HT, 9 with DM, 109 with high LDLc, and 123 were smokers during follow-up. No statistically significant association was found between the presence of CVRF at MS onset and the mentioned clinical outcomes during the MS course., Conclusion: No association was found between CVRFs and the early course of MS in our cohort., (© 2022 S. Karger AG, Basel.)

Background: Patients with relapsing-remitting multiple sclerosis (RRMS) most commonly experience their first symptoms between 20 and 40 years of age. The objective of this study was to investigate how the age at which the first symptoms of RRMS occur has changed over the past decades., Methods: Patients who were followed up in our unit after an initial diagnosis of RRMS using the Poser or McDonald criteria and who experienced their first symptoms between January 1970 and December 2019 were included in the study. The cohort was divided into five groups according to the decade in which the first symptoms appeared. The age at disease onset was compared across decades. Changes in age were also determined after excluding patients with early-onset disease (<18 years of age) and those with late-onset disease (>50 years of age) to avoid bias., Results: The cohort included 1,622 patients with RRMS, 67.6% of whom were women. Among them, 5.9% and 4% had early-onset and late-onset disease, respectively. The mean age ± standard deviation at onset was 31.11 ± 9.82 years, with no differences between men and women. The mean ages at onset were 23.79 ± 10.19 years between 1970 and 1979, 27.86 ± 9.22 years between 1980 and 1989, 30.07 ± 9.32 years between 1990 and 1999, 32.12 ± 9.47 between 2000 and 2009, and 34.28 ± 9.83 years between 2010 and 2019. The ages at disease onset were progressively higher in the later decades; this trend was statistically significant (p < 0.001), with a Pearson linear correlation coefficient R of 0.264 and R 2 of 0.070 (p < 0.001). The results were similar when analysing men and women separately. We conducted an analysis of 1,460 patients (mean age at onset: 31.10 ± 7.99 years), after excluding patients with early-onset and late-onset disease. In this specific subgroup, the mean ages at disease onset were 28.38 ± 8.17 years between 1970 and 1979, 29.22 ± 7.51 years between 1980 and 1989, 30.06 ± 8.02 years between 1990 and 1999, 31.46 ± 7.77 years between 2000 and 2009, and 33.37 ± 7.97 years between 2010 and 2019. The trend was also statistically significant (p < 0.001), with a Pearson linear correlation coefficient R of 0.193 and R 2 of 0.037 (p < 0.001)., Conclusion: Our data showed that the age at RRMS onset has increased over the past decades., Competing Interests: Declaration of Competing Interest Lucía Romero-Pinel, Laura Bau, Elisabet Matas, Isabel León, Albert Muñoz-Vendrell, Pablo Arroyo, Antonio Martínez-Yélamos, and Sergio Martínez-Yélamos received honoraria for participating on advisory boards and for collaborations as consultants and scientific communications; they also received research support as well as funding for travel and congress-attending expenses from Roche, Biogen Idec, Novartis, TEVA, Merck, Genzyme, Sanofi, Bayer, Almirall, and Celgene. Cristina Masuet-Aumatell received honoraria for participating on advisory boards and for collaborations as a consultant and scientific communications and has received research support as well as funding for travel and congress-related expenses from GlaxoSmithKline, Pfizer, Seqirus, Emergent and Sanofi Pasteur., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: The efficacy and safety of disease-modifying therapies (DMTs) in multiple sclerosis (MS) are well known; however, owing to their high costs, determining real-world outcomes is essential to evaluate the cost-effectiveness of different therapeutic strategies. This study aimed to investigate the variability in the annual cost of DMTs associated with a relapse-free patient in a representative population cohort of relapsing-remitting MS (RRMS), and whether this could serve as an appropriate health indicator., Methods: We analyzed the patients followed up in our MS clinic during the years 2016 and 2019, and selected patients belonging to our health district diagnosed with RRMS. The treatment cost associated with a relapse-free patient was the ratio between the total cost of DMTs and the number of relapse-free patients, treated and not treated, during the year of the study., Results: A total of 158 patients with RRMS in 2016 and 183 in 2019 were included in our study. In 2016, 101 patients with RRMS (63.9%) received treatment with DMTs and 120 patients (75.9%) remained relapse-free. The mean cost of DMTs per patient in 2016 was €7414.3 (95% confidence interval [CI]: 6325.2-8503.4) considering all the patients (treated and not treated). In 2019, 126 patients (68.9%) received DMTs and 151 patients (82.5%) remained relapse-free. The mean cost of DMTs per patient in 2019 was €6985.4 (95% CI: 5986.9-7983.9) considering all the patients. The cost per year of DMTs to achieve a relapse-free patient was €9762.2 in 2016 and €8465.8 in 2019., Conclusions: The treatment cost per year to achieve a relapse-free patient was stable during successive measurements in the same population. Therefore, it may be considered a good real-world health indicator for patients with RRMS treated with DMTs., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: Lucía Romero-Pinel, Laura Bau, Elisabet Matas, Sergio Martínez-Yélamos and Antonio Martínez Yélamos received honoraria compensation to participate in advisory boards, collaborations as a consultant and scientific communications and received research support, funding for travel and congress expenses from Biogen Idec, Novartis, TEVA, MerckSerono, Genzyme, Almirall, Bayer and Roche. Isabel León, Roser Juvany and Ramon Jódar declare nothing to disclose.

Treatment options for patients with pancreatic cancer are limited and survival prospects have barely changed over the past 4 decades. Chemoradiation treatment (CRT) has been used as neoadjuvant therapy in patients with borderline resectable disease to reduce tumour burden and increase the proportion of patients eligible for surgery. Antimetabolite drugs such as gemcitabine and 5-fluorouracil are known to sensitise pancreatic tumours to radiation treatment. Likewise, photodynamic therapy (PDT) has also been shown to enhance the effect of radiation therapy. However, PDT is limited to treating superficial lesions due to the attenuation of light by tissue. The ability of the related technique, sonodynamic therapy (SDT), to enhance CRT was investigated in two murine models of pancreatic cancer (PSN-1 and BxPC-3) in this study. SDT uses low intensity ultrasound to activate an otherwise non-toxic sensitiser, generating toxic levels of reactive oxygen species (ROS) locally. It is applicable to greater target depths than PDT due to the ability of ultrasound to propagate further than light in tissue. Both CRT and the combination of CRT plus SDT delayed tumour growth in the two tumour models. In the PSN-1 model, but not the BxPC-3 model, the combination treatment caused an increase in survival relative to CRT alone (p = 0.038). The improvement in survival conferred by the addition of SDT in this model may be related to differences in tumour architecture between the two models. MRI and US images showed that PSN-1 tumours were less well perfused and vascularised than BxPC-3 tumours. This poor vascularisation may explain why PSN-1 tumours were more susceptible to the effects of vascular damage exerted by SDT treatment., (Copyright © 2021. Published by Elsevier B.V.)