Attosecond and nano-Coulomb electron bunches via the Zero Vector Potential mechanism

The commissioning of multi-petawatt class laser facilities around the world is gathering pace. One of the primary motivations for these investments is the acceleration of high-quality, low-emittance electron bunches. Here we explore the interaction of a high-intensity femtosecond laser pulse with a mass-limited dense target to produce MeV attosecond electron bunches in transmission and confirm with three-dimensional simulation that such bunches have low emittance and nano-Coulomb charge. We then perform a large parameter scan from non-relativistic laser intensities to the laser-QED regime and from the critical plasma density to beyond solid density to demonstrate that the electron bunch energies and the laser pulse energy absorption into the plasma can be quantitatively described via the Zero Vector Potential mechanism. These results have wide-ranging implications for future particle accelerator science and associated technologies.

CAnceR IN PreGnancy (CARING) - a retrospective study of cancer diagnosed during pregnancy in the United Kingdom

BACKGROUND

The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population.

METHODS

In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020).

RESULTS

Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%.

CONCLUSIONS

This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.

A treadmill exercise reduced cardiac fibrosis, inflammation and vulnerability to ischemia-reperfusion in rat pristane-induced arthritis

AIMS

To explore cardiac structural and functional parameters and myocardial sensitivity to ischemia in a rat model of chronic arthritis, pristane-induced arthritis (PIA), and to investigate the effects of a running exercise protocol on cardiac disorders related to rheumatoid arthritis (RA).

MAIN METHODS

3 groups of male Dark Agouti rats were formed: Controls, PIA and PIA-Exercise. The PIA-Exercise group was subjected to an individualized treadmill running protocol during the remission phase. At acute and chronic phases of PIA, cardiac structure was analyzed by histology. Cardiac function was explored in isolated hearts to measure left ventricular developed pressure (LVDP), cardiac compliance and infarct size before and after ischemia/reperfusion. Cardiac inflammation was evaluated through VCAM-1 mRNA expression by RT-qPCR. Plasma irisin levels were measured by ELISA.

KEY FINDINGS

PIA rats exhibited myocardial hypertrophy fibrosis and inflammation at the 2 inflammatory phases of the model. At chronic phase only, LVDP and cardiac compliance were lower in PIA compared to controls. As compared to sedentary PIA, exercise did not change cardiac function but reduced fibrosis, inflammation, infarct size, and arthritis severity and increased irisin levels. Cardiac inflammation positively correlated with fibrosis, while irisin levels negatively correlated with cardiac inflammation and fibrosis.

SIGNIFICANCE

In the PIA model that recapitulated most cardiac disorders of RA, a daily program of treadmill running alleviated cardiac fibrosis and inflammation and improved resistance to ischemia. These data provide arguments to promote the practice of exercise in RA patients for cardiac diseases prevention.

Design and Synthesis of Multi-Functional Ligands through Hantzsch Reaction: Targeting Ca2+ Channels, Activating Nrf2 and Possessing Cathepsin S Inhibitory, and Antioxidant Properties

This work relates to the design and synthesis of a series of novel multi-target directed ligands (MTDLs), i.e., compounds 4a-l, via a convenient one-pot three-component Hantzsch reaction. This approach targeted calcium channel antagonism, antioxidant capacity, cathepsin S inhibition, and interference with Nrf2 transcriptional activation. Of these MTDLs, 4i emerged as a promising compound, demonstrating robust antioxidant activity, the ability to activate Nrf2-ARE pathways, as well as calcium channel blockade and cathepsin S inhibition. Dihydropyridine 4i represents the first example of an MTDL that combines these biological activities.

Predation risk drives long-term shifts in migratory behaviour and demography in a large herbivore population

Migration is an adaptive life-history strategy across taxa that helps individuals maximise fitness by obtaining forage and avoiding predation risk. The mechanisms driving migratory changes are poorly understood, and links between migratory behaviour, space use, and demographic consequences are rare. Here, we use a nearly 20-year record of individual-based monitoring of a large herbivore, elk (Cervus canadensis) to test hypotheses for changing patterns of migration in and adjacent to a large protected area in Banff National Park (BNP), Canada. We test whether bottom-up (forage quality) or top-down (predation risk) factors explained trends in (i) the proportion of individuals using 5 different migratory tactics, (ii) differences in survival rates of migratory tactics during migration and whilst on summer ranges, (iii) cause-specific mortality by wolves and grizzly bears, and (iv) population abundance. We found dramatic shifts in migration consistent with behavioural plasticity in individual choice of annual migratory routes. Shifts were inconsistent with exposure to the bottom-up benefits of migration. Instead, exposure to landscape gradients in predation risk caused by exploitation outside the protected area drove migratory shifts. Carnivore exploitation outside the protected area led to higher survival rates for female elk remaining resident or migrating outside the protected area. Cause-specific mortality aligned with exposure to predation risk along migratory routes and summer ranges. Wolf predation risk was higher on migratory routes than summer ranges of montane-migrant tactics, but wolf predation risk traded-off with heightened risk from grizzly bears on summer ranges. A novel eastern migrant tactic emerged following a large forest fire that enhanced forage in an area with lower predation risk outside of the protected area. The changes in migratory behaviour translated to population abundance, where abundance of the montane-migratory tactics declined over time. The presence of diverse migratory life histories maintained a higher total population abundance than would have been the case with only one migratory tactic in the population. Our study demonstrates the complex ways in which migratory populations change over time through behavioural plasticity and associated demographic consequences because of individuals balancing predation risk and forage trade-offs.

Reporting of paediatric osteoporotic vertebral fractures in Duchenne muscular dystrophy and potential impact on clinical management: the need for standardised and structured reporting

BACKGROUND

In boys with Duchenne muscular dystrophy (DMD), initiation of bisphosphonate is recommended upon identification of moderate or severe vertebral fractures, even if asymptomatic. Clear radiological reporting is important for consistency of clinical interpretation and management.

OBJECTIVES

To audit radiology reports of spine imaging for vertebral fracture assessment in DMD, and assess potential impact on diagnosis and management.

MATERIALS AND METHODS

Lateral thoracolumbar spine imaging (71 lateral spine radiographs and 13 lateral dual energy absorptiometry spine image) in 84 boys with DMD performed across two centres. Anonymised radiology reports by paediatric radiologists were circulated to two neuromuscular clinicians and two endocrinologists. Clinicians determined if there was vertebral fracture, no vertebral fracture, or unclear interpretation. Endocrinologists also determined if bisphosphonate was indicated. A single observer (a clinician with expertise in vertebral fracture assessment) performed vertebral fracture assessment in 37 images and re-reported using a structured format. Structured reports were re-circulated to the four clinicians to re-evaluate the degree of concordance in clinical diagnosis of vertebral fracture and treatment decisions with bisphosphonate.

RESULTS

The term "fracture" was used in 25/84 (30%) radiology reports and only in 8/43 (19%) with description of vertebral body abnormalities. Fracture grading was included in 7/43 (16%) radiology reports. Diagnostic concordance by the clinicians was noted in 36/84 (43%). Unclear interpretation was noted in 22% to 51% based on radiology reports. No unclear interpretation was noted with structured reports. Complete diagnostic (37/37, 100%) and treatment (37/37, 100%) concordance was noted with the structured reports, whereas complete diagnostic and treatment concordance was noted in only 16/37 (43%) and 17/37 (46%) of the radiology reports, respectively.

CONCLUSION

Only a third of radiology reports of spine imaging in DMD explicitly used the terminology "fracture". Grading was only noted in a small percentage. Variability in diagnostic interpretation by clinicians may lead to differing management plans. As identification of vertebral fracture is a trigger for treatment, developing reporting guidelines for paediatric vertebral fracture assessment will improve care. A structured template should be introduced for radiological reporting of paediatric vertebral fracture assessment.

Standardization of radiograph readings during bowel management week

INTRODUCTION

During "bowel management week," abdominal radiographs are used to monitor the amount and location of stool. A radiologist familiar with the treatment plan can provide an improved interpretation. The goal of this paper is to standardize the radiological reports during a bowel management week.

METHODS

We saw 744 patients during bowel management week from May 2016 until March 2023. Diagnosis included: anorectal malformation (397), idiopathic constipation (180), Hirschsprung disease (89), and spina bifida (78). Laxatives were the treatment for 51% of patients, and 49% received enemas. Characteristic radiographs were selected for each treatment group for a proposed reading standardization.

RESULTS

When the stool is visualized, it is crucial to report its location. Having a contrast enema helps with the correct interpretation of the colonic anatomy. It is also essential to always compare the amount of stool with the radiograph from the previous day to determine if there is an increase or decrease in stool. Examples of radiographs are shown to guide the use of the preferred proposed terminology.

CONCLUSION

Providing information regarding which treatment modality the patient is receiving and stating that a patient is on a bowel management week treatment is crucial for the radiologist to provide adequate interpretation. The radiologist must be familiar with the treatment goals and purpose of the daily radiograph.

Exploring the Potential of Sulfonamide-Dihydropyridine Hybrids as Multitargeted Ligands for Alzheimer's Disease Treatment

Alzheimer's disease (AD) is a multifactorial neurodegenerative disease that has a heavy social and economic impact on all societies and for which there is still no cure. Multitarget-directed ligands (MTDLs) seem to be a promising therapeutic strategy for finding an effective treatment for this disease. For this purpose, new MTDLs were designed and synthesized in three steps by simple and cost-efficient procedures targeting calcium channel blockade, cholinesterase inhibition, and antioxidant activity. The biological and physicochemical results collected in this study allowed us the identification two sulfonamide-dihydropyridine hybrids showing simultaneous cholinesterase inhibition, calcium channel blockade, antioxidant capacity and Nrf2-ARE activating effect, that deserve to be further investigated for AD therapy.

Biginelli Reaction Synthesis of Novel Multitarget-Directed Ligands with Ca2+ Channel Blocking Ability, Cholinesterase Inhibition, Antioxidant Capacity, and Nrf2 Activation

Novel multitarget-directed ligands BIGI 4a-d and BIGI 5a-d were designed and synthesized with a simple and cost-efficient procedure via a one-pot three-component Biginelli reaction targeting acetyl-/butyrylcholinesterases inhibition, calcium channel antagonism, and antioxidant ability. Among these multitarget-directed ligands, BIGI 4b, BIGI 4d, and BIGI 5b were identified as promising new hit compounds showing in vitro balanced activities toward the recognized AD targets. In addition, these compounds showed suitable physicochemical properties and a good druglikeness score predicted by Data Warrior software.

POS0418 ICE CRYOTHERAPY: A NEW STRATEGY TO REDUCE ARTERIAL INFLAMMATION IN RHEUMATOID ARTHRITIS? A STUDY IN ADJUVANT-INDUCED ARTHRITIS MODEL

Background

Rheumatoid arthritis (RA) is characterized by endothelial activation (EA), endothelial dysfunction and vascular inflammation, leading to accelerated atherosclerosis. In the last decade, a renewed interest in cryotherapy - local or whole body - has emerged. Although growing evidence demonstrated that ice cryotherapy reduces not only pain but also disease progression, whether such therapy might blunt disorders of the systemic vasculature is unknown.

Objectives

The aim of our study was to determine the effects of a subchronic treatment with ice cryotherapy on aortic leucocyte infiltration and markers of endothelial activation in the rat adjuvant-induced arthritis (AIA) model.

Methods

AIA was induced by injection of Mycobacterium butyricum in Freund’s incomplete adjuvant at the base of the tail in 6-week-old male Lewis rats. AIA rats were treated or not with ice applied on paws, from the onset of arthritis to the acute inflammatory stage of the disease, twice a day for 14 days. Arthritis score and paw skin temperature were daily monitored. At the end of the treatment, leucocyte infiltration and the different cell subsets (monocytes/macrophages, neutrophils, CD4+ and CD8+ T cells producing or not IL-17A) were measured in thoracic aorta using flow cytometry. Relative mRNA expression of cytokines/chemokines (IL-6, TNF-α, CXCL-1, MIP-1α (CCL-3), MCP-1 (CCL-2)) and adhesion molecules (ICAM-1, VCAM-1) was analyzed in thoracic aorta by RT-qPCR. X-Ray analysis of hind paws was performed to assign a radiographic score.

Results

Treatment with ice cryotherapy, that decreased skin surface temperature from 28.6 ± 0.3°C to 18.5 ± 0.2°C, reduced arthritis score (-36%, p<0.001) and radiographic score (-34%, p<0.05) with a positive effect on osteoporosis, cartilage and bone destruction. These effects were associated with a dramatic decrease in CD4+, CD8+ and Tc17 cell aortic infiltration as compared to untreated AIA. By contrast, ice had no effect on endothelial activation markers except VCAM-1 mRNA expression that was significantly increased (p<0.05). A positive correlation was found between the number of total leucocytes, monocytes/macrophages, CD4+ and CD8+ T cells in aorta and arthritis score.

Conclusion

In the model of AIA that reproduces arterial wall inflammation recently characterized in rheumatoid arthritis by PET/CT [1], local ice cryotherapy exerts not only local beneficial effects on the joints but also systemic benefits on vascular inflammation in large vessels. These results suggest that reduction of vascular comorbidities might be a new output of ice cryotherapy used as an adjunctive therapy in RA.

References

[1]Agca et al. Rheumatology (Oxford) (2021)

Disclosure of Interests

None declared.

Effects of local cryotherapy on systemic endothelial activation, dysfunction, and vascular inflammation in adjuvant-induced arthritis (AIA) rats

Aim

This study explored the systemic vascular effects of local cryotherapy with a focus on endothelial changes and arterial inflammation in the model of rat adjuvant-induced arthritis (AIA).

Methods

Cryotherapy was applied twice a day on hind paws of AIA rats from the onset of arthritis to the acute inflammatory phase. Endothelial activation was studied in the aorta by measuring the mRNA levels of chemokines (CXCL-1, MCP-1 (CCL-2), MIP-1α (CCL-3)) and adhesion molecules (ICAM-1, VCAM-1) by qRT-PCR. Endothelial dysfunction was measured in isolated aortic and mesenteric rings. Aortic inflammation was evaluated via the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-6) by qRT-PCR and leucocyte infiltration analysis (flow cytometry). Plasma levels of TNF-α, IL-6, IL-1β, IL-17A, and osteoprotegerin (OPG) were measured using Multiplex/ELISA.

Results

AIA was associated with an increased aortic expression of CXCL-1 and ICAM-1 as well as an infiltration of leucocytes and increased mRNA expression of IL-6, IL-1β, and TNF-α. Local cryotherapy, which decreased arthritis score and structural damages, reduced aortic mRNA expression of CXCL-1, IL-6, IL-1β, and TNF-α, as well as aortic infiltration of leucocytes (T lymphocytes, monocytes/macrophages, neutrophils) and improved acetylcholine-induced vasorelaxation in the aorta and mesenteric arteries. Plasma levels of IL-17A and OPG were significantly reduced by cryotherapy, while the number of circulating leucocytes was not. IL-17A levels positively correlated with endothelial activation and dysfunction.

Conclusion

In the AIA model, local cryotherapy reduced systemic endothelial activation, immune cell infiltration, and endothelial dysfunction. Mechanistically, the reduction of circulating levels of IL-17A appears as the possible link between joint cooling and the remote vascular effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02774-1.

AB0073 INTESTINAL PERMEABILITY IN SPONDYLOARTHRITIS: A SYSTEMATIC REVIEW OF THE LITERATURE

Background:

Growing evidence argue for a role of the gut in the pathophysiology of various chronic rheumatic diseases such as spondyloarthritis (SpA). This so-called “gut-joint axis” involves dysbiosis, bacterial translocation, intestinal inflammation and increase in intestinal permeability. Recent data from clinical and basic research suggested that the integrity of the intestinal barrier might be a key determinant in translating autoimmunity to inflammation, making intestinal permeability a potential marker or a target for future therapies.

Objectives:

To analyse the available data on intestinal permeability in SpA patients and the effects of drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) on intestinal permeability.

Methods:

A systematic review was conducted. Without date restriction, the following databases were searched through September 1, 2020: Medline, Embase and Cochrane. Studies with patients with SpA assessing the intestinal permeability were selected. Some of the included studies have assessed the effect of NSAIDs on intestinal permeability.

Results:

A total of 12 studies were included in the final analysis. The 12 studies involved a total of 268 SpA patients, including 240 ankylosing spondylitis (AS). Among the studies included, four studies used the lactulose/mannitol test, four studies used the 51Cr-ethylenediaminetetraacetic test and two studies used the polyethylene glycols test. Nine of the 12 studies reported increased intestinal permeability regardless on the method used for intestinal permeability evaluation. Four studies evaluated the link between disease activity, assessed by CRP and ESR levels, and intestinal permeability and showed no correlation between increased intestinal permeability and markers of disease activity in AS patients. As regards the effects of NSAIDs on intestinal permeability, data are controversial. Two studies, including one evaluating indomethacin, did not show any influence of NSAIDs in AS patients, one study showed an increase in intestinal permeability under NSAIDs in only 60% of the patients, another study reported increased intestinal permeability. When comparing the effect of NSAIDs in patients with AS to healthy subjects, one study reported a comparable NSAIDs-induced increase in intestinal permeability in both groups.

Conclusion:

The results of our review suggest that increased intestinal permeability is present in SpA patients even in the absence of NSAIDs use and regardless of the method used to assess intestinal permeability. The effects of NSAIDs on intestinal permeability in SpA patients is more controversial and further studies are needed to clarify them.

Disclosure of Interests:

None declared

AB0062 TIME COURSE OF INTESTINAL PERMEABILITY AND BACTERIAL TRANSLOCATION IN THE MODEL OF ADJUVANT-INDUCED ARTHRITIS

Background:

Intestinal inflammation, dysbiosis, intestinal permeability (IP) and bacterial translocation (BT) have been identified in patients with spondyloarthritis but the time at which they appear and their contribution to the pathogenesis of the disease is still a matter of debate.

Objectives:

To investigate the time-course of intestinal inflammation, IP and BT in a rat model of reactive arthritis, a subgroup of SpA, the adjuvant-induced arthritis model.

Methods:

Adjuvant-induced arthritis (AIA) was induced in 6-week-old male Lewis rats by an injection at the base of the tail of Mycobacterium butyricum with incomplete Freund’s adjuvant (Day (D) 0). Control rats received saline using the same procedure. Body weights and a clinical arthritis score were daily assessed. A group of AIA and control rats (n=15 per group) were euthanized at three different times of arthritis: D4 for the pre-arthritic phase (AIA-preclinical), D11 for the onset of arthritis (AIA-onset) and D28 for the acute phase (AIA-acute). In each group (AIA and control, n=15 per group)), IP was assessed by measuring plasma levels of zonulin (ELISA) and ileal mRNA expression of zonulin and occludin (RT-qPCR), BT was studied by measuring bacterial endotoxins (or LPS, by LCMS2 method), soluble CD-14 (sCD14, ELISA) and ileal mRNA expression of TLR-4, and intestinal inflammation was assessed by measuring ileal mRNA expression of IL-8, IL-33, IL-17, IL-23p19 and TNF-α (RT-qPCR). Joint damage was assessed by the determination of a clinical and radiographic score of hind paws.

Results:

Body weights of AIA rats decreased from D4 to D28 as compared to controls, in parallel to the development of a severe clinical and radiographic arthritic disease from D11 and D28. Compared to control rats, AIA induced an increase in plasma zonulin levels at D4, D11 but not at D28. Ileal mRNA zonulin overexpression occurred at D11 while occludin was unchanged. As early as Day 4 (preclinical phase), mRNA of IL-8, IL-33 and IL-17 were overexpressed in ileum from AIA. At Day 11 (onset), overexpression of IL-8 persisted and mRNA of TNF-α and IL-23p19 increased in AIA. Neither LPS levels nor ileal mRNA expression of TLR-4 were changed by arthritis whatever the phase of arthritis. By contrast, blood levels of sCD-14 was significantly increased in the AIA group at all stages of arthritis. No correlation was found between clinical and radiographic arthritis scores and zonulin or LPS levels. Conversely, a negative correlation was observed between intestinal IL-8 mRNA expression and arthritis score (r=-0.3, p=0.02).

Conclusion:

In an animal model of SpA, intestinal inflammation and increased intestinal permeability occur prior to joint inflammation, suggesting a role of these disorders in the pathogenesis of this disease.

Acknowledgements:

I would like to thank the Société Française de Rhumatologie for its support in this work.

Disclosure of Interests:

None declared

One-dimensional hydrodynamic simulations of low convergence ratio direct-drive inertial confinement fusion implosions

Indirect drive inertial confinement fusion experiments with convergence ratios below 17 have been previously shown to be less susceptible to Rayleigh-Taylor hydrodynamic instabilities, making this regime highly interesting for fusion science. Additional limitations imposed on the implosion velocity, in-flight aspect ratio and applied laser power aim to further reduce instability growth, resulting in a new regime where performance can be well represented by one-dimensional (1D) hydrodynamic simulations. A simulation campaign was performed using the 1D radiation-hydrodynamics code HYADES to investigate the performance that could be achieved using direct-drive implosions of liquid layer capsules, over a range of relevant energies. Results include potential gains of 0.19 on LMJ-scale systems and 0.75 on NIF-scale systems, and a reactor-level gain of 54 for an 8.5 MJ implosion. While the use of 1D simulations limits the accuracy of these results, they indicate a sufficiently high level of performance to warrant further investigations and verification of this new low-instability regime. This potentially suggests an attractive new approach to fusion energy. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

Flexible gauge length intrinsic fiber-optic strain sensor using broadband interferometry [Invited]

Monitoring strain is important in precision engineering applications that require maintaining the precise alignments of structures over time, such as those found in machine tools and metrology frames. We present a fiber-optic strain measurement technique based upon broadband interferometry that is variously configurable in terms of gauge length and sensitivity. This is achieved by the use of an unbalanced interrogation interferometer configuration that alleviates the cavity length limit imposed by the temporal coherence of the system. We also demonstrate that dispersion in fiber sensors based on intrinsic Fabry-Perot interferometers must be considered to optimize performance. The possibility of multisensor interrogation using the same optical system is also reported.

Synthesis of Hantzsch Adducts as Cholinesterases and Calcium Flux inhibitors, Antioxidants and Neuroprotectives

We report herein the design, synthesis, biological evaluation, and molecular modelling of new inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), able to block Ca⁺² channels also showing antioxidant and neuroprotective activities. The new MTDL, dialkyl 2,6-dimethyl-4-(4-((5-aminoalkyl)oxy)phenyl)-1,4-dihydropyridine-3,5-dicarboxylate 3a-p, have been obtained via Hantzsch reaction from appropriate and commercially available precursors. Pertinent biological analysis has prompted us to identify MTDL 3h [dimethyl-4-(4-((5-(4-benzylpiperidin-1-yl)pentyl)oxy)phenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate] as an attractive inhibitor of AChE (1.8 μM) and BuChE (2 μM), Ca⁺² channel antagonist (47.72% at 10 μM), and antioxidant (2.54 TE) agent, showing significant neuroprotection 28.68% and 38.29% against H₂O_2, and O/R, respectively, at 0.3 μM, thus being considered a hit-compound for further investigation in our search for anti-Alzheimer's disease agents.

SAT0021 STRUCTURAL EFFECTS OF LOCAL CRYOTHERAPY IN RHEUMATOID ARTHRITIS: A STUDY IN ADJUVANT-INDUCED ARTHRITIS

Background:

The control of joint destruction caused by rheumatoid arthritis (RA) is a key issue in the treatment of this disease. Recent evidence showed that radiographic progression of joint damage occur despite a sharp decrease in disease activity and the use of aggressive Disease Modifying Anti-Rheumatic Drug (DMARD) therapies [1]. Whether alternative treatments such as cryotherapy may have beneficial effects on joint destruction at the early stages of the disease remains to be demonstrated, but such strategy would be of interest as it would not interfere with DMARDs treatment.

Objectives:

The aim of this study was to evaluate the effect of a 14-days-treatment of local cryotherapy on radiological outcomes in rat adjuvant induced arthritis.

Methods:

Adjuvant-induced arthritis (AIA) was induced in 6-weeks old male Lewis rats by injection ofMycobacterium butyricumin Freund’s incomplete adjuvant at the basis of the tail. A control group received saline. At the onset of arthritis, AIA rats were treated or not by application of cryotherapy on paws using either a cold spray or ice, twice a day for 14 days. Arthritis score and paws skin temperature was daily monitored. At the end of treatment, radiological exam of hind paws was performed and a score taking into account (swelling, osteoporosis, cartilage destruction, bone erosion, bone destruction and new bone formation) was assigned, according to Ackermanet al[2]. Circulating levels of cytokines (IL-6, IL-1β, TNF-α) was measured by Magpix Luminex kit.

Results:

Compared to untreated AIA, local cryotherapy significantly reduced the progression of arthritis score, whatever the modality (p<0.05), and to the same extent (reduction of arthritis score at day 24 post-immunization: -38% with cold spray, p<0.01, -37% with ice, p<0.01). Radiological score was significantly reduced by both treatments with no difference between the two treatments (-33% with cold spray, p<0.01, -44% with ice, p<0.01). All the items of the radiological score were equally reduced by ice and cold spray except swelling that was significantly reduced only by ice. Interestingly, the use of the cold spray induced a greater decrease in the skin temperature than the ice treatment (18.32 ± 0.07 °C vs 20.46 ± 0.08 °C, p<0.001). Conversely, cryotherapy did not significantly change the level of cytokines. No correlation was found between radiological score and arthritis score or cytokine levels.

Conclusion:

These data demonstrated that local cryotherapy had positive effects on structural damage in adjuvant-induced arthritis. The mechanisms involved remain now to be determined. These results suggest that local cryotherapy would be an interesting complement to conventional DMARDs in early RA.

References:

[1] Ten Klooster, P. M.et al.Radiographic progression can still occur in individual patients with low or moderate disease activity in the current treat-to-target paradigm: real-world data from the Dutch Rheumatoid Arthritis Monitoring (DREAM) registry.Arthritis Res. Ther.21, 237 (2019).

[2] Ackerman, N. R.et al.Effects of naproxen on connective tissue changes in the adjuvant arthritic rat.Arthritis Rheum.22, 1365–1374 (1979).

Disclosure of Interests:

Célian Peyronnel: None declared, Valentin Petitcolin: None declared, Perle Totoson: None declared, Hélène Martin: None declared, Frank Verhoeven: None declared, Céline Demougeot Grant/research support from: With an institutional support from Pfizer.

Parents' Views on Silver Diamine Fluoride to Manage Early Childhood Caries

BACKGROUND

The use of silver diamine fluoride (SDF) as a nonsurgical caries management product is growing. Evidence suggests that SDF is very successful in arresting caries. However, a common concern with SDF treatment is the unaesthetic black staining. The purpose of this qualitative study was to determine parents' views following their children's treatment with SDF to manage severe early childhood caries (ECC).

METHOD

Parents were interviewed as part of a mixed-method study of SDF to arrest severe ECC. Children with caries lesions in primary teeth were treated with 2 applications of 38% SDF, followed by fluoride varnish. Semistructured in-person and phone interviews were conducted with 19 parents of children in the study. Data were transcribed verbatim and manually coded and uploaded to NVivo 12 for further coding analysis.

RESULTS

None of the parents had previously heard about SDF, and they learned about it from the study dentist. Although parents trusted the dentist's information on SDF, they welcomed additional evidence, especially relating to product safety and effectiveness. Some parents were minimally concerned with the black staining caused by SDF treatment. It was more important that SDF arrested caries progression, minimized pain and sensitivity, and prevented dental infection. However, some parents expressed concerns related to the unaesthetic black staining. Interestingly, many parents indicated that their children were not overly concerned with the black staining. A majority of parents said that they would recommend the treatment to others.

CONCLUSION

This is the first qualitative study involving parents of children who were treated with SDF. Most parents were accepting of SDF as a nonsurgical treatment to arrest caries and minimize dentinal sensitivity secondary to caries, although some expressed concern about the black staining in anterior teeth. It is important to adequately inform parents of the negative aesthetic consequences and obtain informed consent before treatment.

KNOWLEDGE TRANSFER STATEMENT

This qualitative study revealed that many parents of children with severe ECC are accepting of SDF as a nonrestorative caries management option, despite the black staining of caries lesions. Dental professionals need to be aware of these parental concerns and obtain written informed consent prior to treatment. Parents also requested more information and resources on SDF on its benefits, effectiveness, and any associated risks.

Posterolateral plate fixation with Pantalarlock® is more stable than nail fixation in tibiotalocalcaneal arthrodesis in a biomechanical cadaver study

BACKGROUND

Despite the promising results of ankle joint arthroplasty, the tibiotalocalcaneal (TTC) arthrodesis remains an established procedure in treatment of combined pathology of the ankle and subtalar joint. Despite the promising results in biomechanical investigations, nonunion rates of up to 24% are described in recent studies. The objective of this work was a comparative study of the biomechanical properties of the posterolateral plate fixation with retrograde intramedullary nail fixation.

METHODS

Twenty four fresh-frozen human lower leg specimens (12 pairs) were used for the comparative biomechanical testing. Every specimen was preconditioned with 100 N over 200 cycles. After every 250 cycles the force was increased by 50 N from 200 to 600 N. This was followed by cyclic loading in dorsi-/plantiflexion with 800 N for 3000 cycles. All specimens were subjected to bone densitometry (DXA) and computed tomography.

RESULTS

Significantly higher number of spacimens with nails (4) failed during the cycling testing in dorsi-/plantarflexion and futher two during the cyclic testing with 800 N. Two specimens with plates failed during the cyclic testing with 800 N. Statistical analysis showed that the specimens with the plate were significantly more stable in each test direction. The Pearson correlation demonstrated for the specimens with plate a linear relationship between the stiffness and the determined bone density.

CONCLUSIONS

The results demonstrate a significantly superior stiffness of the Pantalarlock®-plate in all testing directions compared with the HAN nail. Probably the position of the plate on the tension side of the joint and the combination of locking and lag screws provide the higher stiffness of the plate system. The correlation of the stiffness with bone density leads to more predictable results of the plate arthrodesis. We hope for a reduction of the pseudarthrosis rate and shorten the postoperative treatment phase. The authors expect advantages in the treatment of high risk patients with severe deformity of the ankle, bone defects, neuropathic deformity, poor bone quality and osteoporosis.

Design, Synthesis and Biological Evaluation of New Antioxidant and Neuroprotective Multitarget Directed Ligands Able to Block Calcium Channels

We report herein the design, synthesis and biological evaluation of new antioxidant and neuroprotective multitarget directed ligands (MTDLs) able to block Ca²⁺ channels. New dialkyl 2,6-dimethyl-4-(4-(prop-2-yn-1-yloxy)phenyl)-1,4-dihydropyridine-3,5-dicarboxylate MTDLs 3a–t, resulting from the juxtaposition of nimodipine, a Ca²⁺ channel antagonist, and rasagiline, a known MAO inhibitor, have been obtained from appropriate and commercially available precursors using a Hantzsch reaction. Pertinent biological analysis has prompted us to identify the MTDL 3,5-dimethyl-2,6–dimethyl–4-[4-(prop–2–yn–1-yloxy)phenyl]-1,4-dihydro- pyridine- 3,5-dicarboxylate (3a), as an attractive antioxidant (1.75 TE), Ca²⁺ channel antagonist (46.95% at 10 μM), showing significant neuroprotection (38%) against H₂O₂ at 10 μM, being considered thus a hit-compound for further investigation in our search for anti-Alzheimer’s disease agents.

Superficial parotidectomy versus extracapsular dissection: literature review and search for a gold standard technique

Benign parotid tumours usually present as a slow-growing, asymptomatic mass in the pre-auricular region. Although they are uncommon, surgical excision is the mainstay of treatment due to the risk of malignant transformation in some benign tumours. Surgical techniques have evolved over the years, with superficial parotidectomy and extracapsular dissection being the current procedures of choice. There is currently no gold standard, and it remains unclear which surgical modality is the superior option. A literature review was performed in relation to the relative merits of each technique and to evaluate the reasons underpinning the ongoing debate. A total of 16 papers comparing the main clinical outcomes of the procedures were critically reviewed using the PRISMA protocol. Overall, extracapsular dissection indicated a reduced recurrence rate, facial nerve paralysis, Frey syndrome, and operation time. The superior outcomes following extracapsular dissection could be attributed to the less radical nature of the procedure. However, there were various limitations identified within the review that may have affected the results. Selection bias was the most significant, with patients assigned to the different procedures depending on the tumour size and location. Consequently, the debate continues as to what constitutes the gold standard of care for benign parotid tumours.

Food-basket intervention to reduce micronutrient deficiencies among Maasai-pregnant women in Tanzania: a quasi-experimental study

BACKGROUND

Micronutrients comprised of vitamin and mineral nutrients that are needed during pregnancy for foetal growth, development and maturation, as well as for reducing/preventing maternal complications. However, micronutrient-rich foods (vegetables and fruits) are lacking in the Ngorongoro Conservation Area as a result of restrictions on cultivation in conservation areas and the unavailability of vegetables and fruits in local markets. The present study introduced a food basket intervention and assessed the effectiveness of the food baskets with respect to addressing anaemia, vitamin A and iron deficiencies among pregnant Maasai women within the Ngorongoro Conservation Area.

METHODS

The quasi-experimental study included Misigiyo ward as a control group (provided education only) and Olbalbal ward as an intervention group (provided food baskets and education). The study assessed haemoglobin, serum ferritin and retinol at baseline and during follow-up. Haemoglobin, serum ferritin and retinol were quantitatively (duplicate) measured with HemoCue™ (HemoCue AB, Ängelholm, Sweden), Maglumi 800 (Snibe Diagnostic, Shenzhen, China) and vitamin A enzyme-linked immunosorbent assay, respectively. Dependent and independent t-tests were used to compare the micronutrient blood levels between and within the groups.

RESULTS

The present study found a statistically significant increase in serum retinol (P < 0.001) in the intervention group compared to the control group; moreover, baseline serum retinol was positively associated with the follow-up serum retinol, whereas baseline haemoglobin and serum ferritin were negatively associated.

CONCLUSIONS

The food basket intervention holds promise with repect to reducing micronutrient deficiency, especially in communities where micronutrient-rich foods are scarce.

Improvements to dispersed reference interferometry: beyond the linear approximation

Interferometric instruments with dispersion introduced in the reference arm have previously been created, as the controlled dispersion can be used to generate a signal that contains a clearly identifiable point, the location of which relates to the position of the scattering surface in the measurement arm. In the following, we illustrate that the linear approximations that have been used previously can lead to significant errors, and that second-order terms need to be included in order to correct this. These corrections are vital if these instruments are to be used for metrological applications.

Nanowire based bioprobes for electrical monitoring of electrogenic cells

The continuous miniaturization of electronic components and the emergence of nano-biotechnology has opened new perspectives to monitor electrical activities at the single cell level. Here, we describe the creation of very high surface-to-volume ratio passive devices (vertical nanowire probes) using large-scale fabrication process, allowing to follow the electrical activity of mammalian neurons. Based on conventional silicon processing, the silicon nanowires were silicided in platinum in order to improve their electrochemical performances and to guarantee their biocompatibility. Very high signal to noise ratio was achieved (up to 2000) when measuring spontaneous action potentials. Moreover, this bio-platform was used to record the impact of various bio-chemical and electrical stimulations on neuronal activity. To conclude, this study proposes a thorough comparison of the characteristics and performances of these new nanowire-based nanoprobes with the main alternative systems published up to now.

[Cutaneous metastases on the extremities]

BACKGROUND

Cutaneous metastases (CM) on the extremities are rare complication of cancer with poor prognosis. In general, lesions simulate an infection. Herein, we report two new cases with atypical presentation.

PATIENTS AND METHODS

Case no 1: a 71-year-old man consulted for suspicion of left hand pyogenic granuloma present for 3 months. His history revealed two treated squamous-cell carcinomas (tongue and lung). On physical examination, he presented three budding and foul-smelling lesions on his left hand. Histopathology showed metastasis of squamous-cell carcinoma. Radiographic examination revealed spread of pulmonary nodules with suspicion of metastasis. Case no 2: a 68-year-old man was hospitalized for indurated edema of the right leg present for several months. Six months earlier, he had undergone surgery for left pulmonary adenocarcinoma without metastasis. Physical examination revealed an indurated edema on the right foot. Histopathology showed metastasis from adenocarcinoma. A scan revealed several osteolytic lesions in the right foot as well as lymphadenopathy.

DISCUSSION

Herein, we report two original cases of CM of the extremities diagnosed as tumor progression. This is a rare complication of variable clinical presentation and impacts both cancer management and prognosis. It is important to consider the diagnosis when distal cutaneous lesions persist, particularly where there is a history of cancer.