A Randomised Phase II Trial to Evaluate the Feasibility of Radiotherapy Dose Escalation, Facilitated by Intensity-Modulated Arc Radiotherapy Techniques, in High-Risk Neuroblastoma

BACKGROUND AND PURPOSE

For high-risk neuroblastoma, planning target volume coverage is often compromised to respect adjacent kidney tolerance. This trial investigated whether intensity-modulated arc radiotherapy techniques (IMAT) could facilitate dose escalation better than conventional techniques.

MATERIALS AND METHODS

Children with high-risk abdominal neuroblastoma referred for radiotherapy to the primary tumour site and involved regional lymph nodes were randomised to receive either standard dose (21 Gy in 14 fractions) or escalated dose (36 Gy in 24 fractions) radiotherapy. Dual planning with both a conventional anterior-posterior parallel opposed pair radiotherapy technique and an IMAT technique was performed. The quality of target volume and organ-at-risk delineation, and dosimetric plans, were externally reviewed. Dosimetric parameters were used to judge the superior technique for treatment. This feasibility trial was not powered to detect improvement in outcome with dose escalation.

RESULTS

Between 2017 and 2020, 50 patients were randomised and dual-planned. The IMAT technique was judged more favourable in 48 patients. In all patients randomised to receive 36 Gy, IMAT would have permitted delivery of the full dose (median D50% 36.0 Gy, inter-quartile range 36.0-36.1 Gy) to the target volume, whereas dose compromise would have been required with conventional planning (median D50% 35.6 Gy, inter-quartile range 28.7-35.9 Gy).

CONCLUSION

IMAT facilitates safe dose escalation to 36 Gy in patients receiving radiotherapy for neuroblastoma. The value of dose escalation is now being evaluated in a current prospective phase III randomised trial.

Broadening Perspectives of Artificial Intelligence in Echocardiography

Echocardiography frequently serves as the first-line treatment of diagnostic imaging for several pathological entities in cardiology. Artificial intelligence (AI) has been growing substantially in information technology and various commercial industries. Machine learning (ML), a branch of AI, has been shown to expand the capabilities and potential of echocardiography. ML algorithms expand the field of echocardiography by automated assessment of the ejection fraction and left ventricular function, integrating novel approaches such as speckle tracking or tissue Doppler echocardiography or vector flow mapping, improved phenotyping, distinguishing between cardiac conditions, and incorporating information from mobile health and genomics. In this review article, we assess the impact of AI and ML in echocardiography.

Fully Automated Measurement of the Insall-Salvati Ratio with Artificial Intelligence

Patella alta (PA) and patella baja (PB) affect 1-2% of the world population, but are often underreported, leading to potential complications like osteoarthritis. The Insall-Salvati ratio (ISR) is commonly used to diagnose patellar height abnormalities. Artificial intelligence (AI) keypoint models show promising accuracy in measuring and detecting these abnormalities.An AI keypoint model is developed and validated to study the Insall-Salvati ratio on a random population sample of lateral knee radiographs. A keypoint model was trained and internally validated with 689 lateral knee radiographs from five sites in a multi-hospital urban healthcare system after IRB approval. A total of 116 lateral knee radiographs from a sixth site were used for external validation. Distance error (mm), Pearson correlation, and Bland-Altman plots were used to evaluate model performance. On a random sample of 2647 different lateral knee radiographs, mean and standard deviation were used to calculate the normal distribution of ISR. A keypoint detection model had mean distance error of 2.57 ± 2.44 mm on internal validation data and 2.73 ± 2.86 mm on external validation data. Pearson correlation between labeled and predicted Insall-Salvati ratios was 0.82 [95% CI 0.76-0.86] on internal validation and 0.75 [0.66-0.82] on external validation. For the population sample of 2647 patients, there was mean ISR of 1.11 ± 0.21. Patellar height abnormalities were underreported in radiology reports from the population sample. AI keypoint models consistently measure ISR on knee radiographs. Future models can enable radiologists to study musculoskeletal measurements on larger population samples and enhance our understanding of normal and abnormal ranges.

Reattachment of Fractured Tooth: A Comprehensive Review

Dental trauma is one of the most prevalent problems encountered in clinical practice. Traumatic injuries involving fractures of the anterior tooth are one of the most common problems among children and adolescents. There is a physical and social impact on patients' quality of life due to traumatic dental injuries (TDIs). Children and adolescents frequently present with a crown fracture that necessitates immediate intervention. Clinicians need to be aware of various treatment modalities for TDIs and have to address these injuries immediately. Due to advances in adhesive technologies, fragment reattachment is the treatment of choice when the fragment is available and well stored. The purpose of this article is to cover various techniques for reattaching fractured fragments and the most current developments in adhesive systems for this purpose.

Metal Marvels: Revolutionizing Endodontic Restoration With a Novel Endocrown Approach

This case report explores the innovative application of the endocrown technique for restoring a severely damaged mandibular molar (tooth #46) in a 28-year-old male patient. With a recent root canal treatment history, the patient presented with a dislodged prosthesis. Due to financial constraints, a base metal alloy was chosen for the endocrown restoration. The unique preparation process involved reducing the occlusal surface by 2 mm, creating a shoulder cervical margin, and preserving enamel walls. The endocrown, crafted from a base metal alloy, demonstrated a semi-conservative approach, providing cost-effectiveness and minimal tooth preparation. The case adheres to the 2013 CAse REport (CARE) guidelines. The discussion highlights the biomechanical benefits of the endocrown, emphasizing stress resistance, stability, and superior performance compared to traditional treatments. Materials like ceramic, resin nanoceramic, and polyetheretherketone are briefly discussed, focusing on the promising success rates of endocrowns, mainly through computer-aided designing/computer-aided manufacturing systems. The report provides valuable insights for clinicians considering this endocrown technique in reconstructing severely damaged molars and premolars.

Dual carbon isotope-based brown carbon aerosol characteristics at a high-altitude site in the northeastern Himalayas: Role of biomass burning

PM2.5 samples (n = 34) were collected from January to April 2017 over Shillong (25.7°N, 91.9°E; 1064 m amsl), a high-altitude site situated in the northeastern Himalaya. The main aim was to understand the sources, characteristics, and optical properties of local vs long-range transported carbonaceous aerosols (CA) using chemical species and dual carbon isotopes (13C and 14C). Percentage biomass burning (BB)/biogenic fraction (fbio, calculated from 14C) varied from 67 to 92 % (78 ± 7) and correlated well with primary BB tracers like f60, and K+, suggesting BB as a considerable source. Rain events are shown to reduce the fbio fraction, indicating majority of BB-derived CA are transported. Further, δ13C (-26.6 ± 0.4) variability was very low over Shillong, suggesting it's limitations in source apportionment over the study region, if used alone. Average ratio of absorption coefficient of methanol-soluble BrC (BrCMS) to water-soluble BrC (BrCWS) at 365 nm was 1.8, indicating a significant part of BrC was water-insoluble. A good positive correlation between fbio and mass absorption efficiency of BrCWS and BrCMS at 365 nm with the higher slope for BrCMS suggests BB derived water-insoluble BrC was more absorbing. Relative radiative forcing (RRF, 300 to 2500 nm) of BrCWS and BrCMS with respect to EC were 11 ± 5 % and 23 ± 16 %, respectively. Further, the RRF of BrCMS was up to 60 %, and that of BrCWS was up to 22 % with respect to EC for the samples with fbio ≥ 0.85 (i.e., dominated by BB), reflecting the importance of BB in BrC RRF estimation.

Use of Suprapubic Panniculus for Split-Thickness Skin Graft in Buried Penis Repair

Background

In the United States, acquired buried penis deformity is an increasingly more common condition. Management of the buried penis deformity is accomplished with removal of macerated skin and subcutaneous tissue from the panniculus and prepubic region, and replacement of denuded penile skin. If local tissue advancement is insufficient to cover the defect, a skin graft may be required. Though the anterior thigh is commonly used, this creates a second defect. Here we describe 2 cases of split-thickness skin grafts harvested from the panniculus to cover buried penis deformities.

Methods

Two patients with a buried penis deformity were identified. The denuded suprapubic tissue was elevated. Using inferior traction, split-thickness skin grafts were harvested and placed onto the shaft of the penis. The remaining excess tissue was resected.

Results

One patient had a fungal rash that resolved with topical treatment. The other patient had a hematoma requiring surgical evacuation. Neither patient had any other complications, and both had over 95% take of the split-thickness skin grafts.

Conclusions

These cases demonstrate the successful use of pannicular skin grafts for buried penis deformity correction. This donor site avoids creation of a second defect. As demonstrated here, the grafts are a durable option, even in the setting of local infection and hematoma.

Comparative Evaluation of the Efficacy of TheraCal LC, Mineral Trioxide Aggregate, and Biodentine As Direct Pulp Capping Materials in Patients With Pulpal Exposure in Posterior Teeth: A Triple-Blinded Randomized Parallel Group Clinical Trial

Background The aim was to evaluate and compare the efficacy of TheraCal LC, mineral trioxide aggregate (MTA), and Biodentine as direct pulp capping (DPC) materials in patients with pulpal exposure in the posterior teeth. Methodology A total of 54 samples were assessed for eligibility. Out of this, 12 teeth samples failed to meet the inclusion criteria. Finally, 42 teeth samples were selected which were randomly distributed into three groups (n = 14). Groups A, B, and C received the intervention of MTA, Biodentine, and TheraCal LC, respectively. The assessment was performed clinically to check for postoperative pain, tenderness, and neural sensibility, and the radiographs were used to check the presence of periodontal ligament (PDL) space widening, calcified barrier, and periapical radiolucency at the follow-up of 21 days, three months, and 12 months. The outcomes depended on the clinical and radiographic success rates recorded at 12 months of recall. Results Overall successful outcome of DPC clinically at different periods was 97.61% at three months and 88.09% at 12 months. A Chi-square test was used which showed that the difference was statistically nonsignificant. For groups A, B, and C, the success rate at follow-up came out to be 85.71%, 100%, and 78.57% at 12 months, respectively. The overall radiographic success rate of DPC at different time periods was 83.33% at three months and 88.09% at 12 months. A Chi-square test was used which showed that the difference was statistically nonsignificant. For groups A, B, and C, the success rate at follow-up came out to be 85.71%, 100%, and 78.57% at 12 months, respectively. Conclusion Resin-based calcium-silicate agent (TheraCal LC) showed good efficacy and can be used in practice with the predictability of a good success rate both clinically and radiographically. Thus, TheraCal LC can be utilized as an alternative to MTA or Biodentine in clinical practice, with the predictability of similar successful outcomes in patients with pulpal exposure in the posterior teeth.

Pulpotomy for the Management of Irreversible Pulpitis in Mature Teeth

Strict protocols for evaluating the pulp's preoperative state should be developed, along with a new classification scheme for the different pulp states, as case selection plays a major role in the effectiveness of adult pulpotomy. In this case report, a male patient, age 15, who had a carious lower left first molar underwent pulpotomy. The pulp's initial state was ascertained by pulse oximetry, electric pulp testing (EPT), and cold testing. The final diagnosis was symptomatic irreversible pulpitis. A 12-month follow-up period following the placement of mineral trioxide aggregate (MTA) (MTA Angelus Angelus, Londrina, Brazil; Clinician's Choice, New Milford, CT) and tooth-colored composite restoration revealed no visible anomalies in the postoperative radiographs, and the tooth remained functional and free of symptoms.

Novel Ameloblastin Variants, Contrasting Amelogenesis Imperfecta Phenotypes

Amelogenesis imperfecta (AI) comprises a group of rare, inherited disorders with abnormal enamel formation. Ameloblastin (AMBN), the second most abundant enamel matrix protein (EMP), plays a critical role in amelogenesis. Pathogenic biallelic loss-of-function AMBN variants are known to cause recessive hypoplastic AI. A report of a family with dominant hypoplastic AI attributed to AMBN missense change p.Pro357Ser, together with data from animal models, suggests that the consequences of AMBN variants in human AI remain incompletely characterized. Here we describe 5 new pathogenic AMBN variants in 11 individuals with AI. These fall within 3 groups by phenotype. Group 1, consisting of 6 families biallelic for combinations of 4 different variants, have yellow hypoplastic AI with poor-quality enamel, consistent with previous reports. Group 2, with 2 families, appears monoallelic for a variant shared with group 1 and has hypomaturation AI of near-normal enamel volume with pitting. Group 3 includes 3 families, all monoallelic for a fifth variant, which are affected by white hypoplastic AI with a thin intact enamel layer. Three variants, c.209C>G; p.(Ser70*) (groups 1 and 2), c.295T>C; p.(Tyr99His) (group 1), and c.76G>A; p.(Ala26Thr) (group 3) were identified in multiple families. Long-read AMBN locus sequencing revealed these variants are on the same conserved haplotype, implying they originate from a common ancestor. Data presented therefore provide further support for possible dominant as well as recessive inheritance for AMBN-related AI and for multiple contrasting phenotypes. In conclusion, our findings suggest pathogenic AMBN variants have a more complex impact on human AI than previously reported.

Unraveling the Enigma of Managing a Large Periapical Lesion: A Case Report

This case report documents the diagnosis and successful management of a substantial periapical lesion located in the lower left region of the jaw. The patient presented with clinical symptoms indicative of periapical pathology, and radiographic examination revealed an extensive radiolucent lesion. The chosen treatment approach involved endodontic intervention coupled with surgical decompression, leading to the resolution of the lesion and restoration of oral health. This case underscores the significance of an accurate diagnosis and a multidisciplinary treatment approach in addressing large periapical lesions.

mTOR-dependent loss of PON1 secretion and antiphospholipid autoantibody production underlie autoimmunity-mediated cirrhosis in transaldolase deficiency

Transaldolase deficiency predisposes to chronic liver disease progressing from cirrhosis to hepatocellular carcinoma (HCC). Transition from cirrhosis to hepatocarcinogenesis depends on mitochondrial oxidative stress, as controlled by cytosolic aldose metabolism through the pentose phosphate pathway (PPP). Progression to HCC is critically dependent on NADPH depletion and polyol buildup by aldose reductase (AR), while this enzyme protects from carbon trapping in the PPP and growth restriction in TAL deficiency. Although AR inactivation blocked susceptibility to hepatocarcinogenesis, it enhanced growth restriction, carbon trapping in the non-oxidative branch of the PPP and failed to reverse the depletion of glucose 6-phosphate (G6P) and liver cirrhosis. Here, we show that inactivation of the TAL-AR axis results in metabolic stress characterized by reduced mitophagy, enhanced overall autophagy, activation of the mechanistic target of rapamycin (mTOR), diminished glycosylation and secretion of paraoxonase 1 (PON1), production of antiphospholipid autoantibodies (aPL), loss of CD161+ NK cells, and expansion of CD38+ Ito cells, which are responsive to treatment with rapamycin in vivo. The present study thus identifies glycosylation and secretion of PON1 and aPL production as mTOR-dependent regulatory checkpoints of autoimmunity underlying liver cirrhosis in TAL deficiency.

The impact of electronic pathways and digital systems on neck of femur fracture outcomes globally: a systematic review

INTRODUCTION

Electronic pathways (e-pathways) and digital systems are novel interventions with several uses in healthcare, ranging from clinical decision support systems to checklists for care delivery. Their application in the management of neck of femur (NOF) fractures is evolving and they may play a key role in facilitating improvements in care delivery. The primary aim of this review was to outline the impact of e-pathways/digital systems on NOF fracture outcomes.

METHODS

A systematic literature search was performed using the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. A total of 698 citations were evaluated, of which 38 passed the inclusion/exclusion criteria. Six studies were then finalised following full-text review. Heterogenous data meant a narrative synthesis was undertaken. Risk of bias for each paper was assessed using the Downs and Black scale.

RESULTS

A statistically significant improvement was demonstrated for time to theatre (3/6 studies), length of hospital stay (2/6 studies) and secondary fracture prevention (2/6 studies). Although postoperative delirium and mortality improved with the introduction of e-pathways/digital systems, statistical significance was not achieved. No outcome measures were adversely affected.

CONCLUSIONS

This systematic review of the literature demonstrates that e-pathways and digital systems are promising novel interventions, displaying a significant positive impact on several NOF fracture outcomes. Owing to the novel nature of e-pathways and digital systems in orthopaedics, a limited number of studies were identified for review, each with variable study design. More high quality homogenous prospective cohort studies with a standardised primary outcome measure are required for more definitive conclusions of efficacy to be drawn.

Interim Results of a Phase 1/2 Open-Label Study of INO-3107 for HPV-6 and/or HPV-11-Associated Recurrent Respiratory Papillomatosis

OBJECTIVE

To evaluate the safety, immunogenicity, and efficacy of INO-3107, a DNA immunotherapy designed to elicit targeted T-cell responses against human papillomavirus (HPV) types 6 and 11, in adult patients with recurrent respiratory papillomatosis (RRP; NCT04398433).

METHODS

Eligible patients required ≥2 surgical interventions for RRP in the year preceding dosing. INO-3107 was administered by intramuscular (IM) injection followed by electroporation (EP) on weeks 0, 3, 6, and 9. Patients underwent surgical debulking within 14 days prior to first dose, with office laryngoscopy and staging at screening and weeks 6, 11, 26, and 52. Primary endpoint was safety and tolerability, as assessed by treatment-emergent adverse events (TEAEs). Secondary endpoints included frequency of surgical interventions post-INO-3107 and cellular immune responses.

RESULTS

An initial cohort of 21 patients was enrolled between October 2020 and August 2021. Fifteen (71.4%) patients had ≥1 TEAE; 11 (52.4%) were Grade 1, and 3 (14.3%) were Grade 3 (none treatment related). The most frequently reported TEAE was injection site or procedural pain (n = 8; 38.1%). Sixteen (76.2%) patients had fewer surgical interventions in the year following INO-3107 administration, with a median decrease of 3 interventions versus the preceding year. The RRP severity score, modified by Pransky, showed improvement from baseline to week 52. INO-3107 induced durable cellular responses against HPV-6 and HPV-11, with an increase in activated CD4 and CD8 T cells and CD8 cells with lytic potential.

CONCLUSION

The data suggest that INO-3107 administered by IM/EP is tolerable and immunogenic and provides clinical benefit to adults with RRP.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3087-3093, 2023.

Pioneering Periapical Healing: The Novel Synergy of Mineral Trioxide Aggregate and Injectable Platelet-Rich Fibrin

This case report presents a novel non-surgical approach for managing a substantial periapical lesion associated with tooth 12 using a combination of injectable platelet-rich fibrin (i-PRF) and mineral trioxide aggregate (MTA). A 28-year-old male patient presented with pus discharge and intermittent swelling following a history of dental trauma. Clinical and radiographic assessments confirmed a large periapical cyst associated with tooth 12. The treatment involved root canal therapy with calcium hydroxide medication, leading to symptom relief. Subsequently, i-PRF combined with MTA was used as a regenerative material for periapical healing. Follow-up examinations at three, six, and nine months showed complete resolution of symptoms and radiographic evidence of lesion healing. This innovative technique demonstrates the potential of i-PRF and MTA synergy in the non-surgical management of periapical lesions, avoiding the risks associated with surgical interventions and promoting effective tissue healing.

CT vs. MRI: Which is More Accurate in Grading Rectal Wall Infiltration after Hydrogel Spacer Placement for Prostate Cancer Patients?

PURPOSE/OBJECTIVE(S)

The purpose of this study was to evaluate the incidence and severity of rectal wall infiltration (RWI) in prostate cancer patients after rectal hydrogel spacer implantation, a commonly used procedure to minimize rectal radiation exposure during prostate radiotherapy. The study aimed to determine correlation of RWI using computed tomography (CT) scans and magnetic resonance imaging (MRI) scans in order to determine the optimal post-placement imaging modality.

MATERIALS/METHODS

This retrospective study was conducted on 370 patients diagnosed with localized prostate cancer who underwent rectal hydrogel spacer placement from 2020 to 2022. CT scans were performed on all patients, with a smaller subset also undergoing MRI scans. The images were independently evaluated by three radiation oncologists to grade RWI levels using a standardized scoring system based on CT and MRI images after hydrogel placement. The levels were categorized as 0 (no RWI), 1 (focal RWI), 2 (moderate RWI), and 3 (significant RWI).

RESULTS

Any grade of RWI was identified in 79.8% of men with the majority (41%) being RWI grade 1. The median time for CT scans was 9 days after hydrogel spacer placement and 14.5 days for MRI scans. For the subset of patients with both CT and MRI scans after spacer (mostly SpaceOAR Vue), RWI was detected in 58.33% of patients based on CT and 61.11% of patients based on MRI. Table 1 shows the mean percentage of patients with each score of RWI for each imaging modality. MRI was more likely to lead to a designation of RWI of any grade compared to CT and more often led to detection of RWI grades 2-3.

CONCLUSION

Our findings demonstrate that the incidence and severity of RWI may be higher than previously reported in clinical trials and that MRI may be a more sensitive imaging modality. Caution is needed in the utilization of rectal spacer gels given the potential for complications with misplacement prior to radiation therapy. Further study is warranted to determine the potential impact of low-grade RWI on the safety of subsequent treatment.

Application of Low-Level Laser Therapy in Endodontics: A Narrative Review

Low-level laser therapy (LLLT) stands out in the realm of dentistry for its unique attributes that set it apart from traditional therapeutic approaches. This non-invasive and painless modality harnesses the power of low-intensity lasers, offering a distinct advantage in terms of safety and patient comfort. Unlike many conventional methods, LLLT does not rely on pharmaceutical interventions or invasive procedures, making it a gentle yet effective option for various dental applications. Its non-thermal, photobiomodulatory effects on cellular and tissue functions mark a notable departure from the more aggressive treatment modalities commonly associated with dentistry. This article provides an extensive exploration of LLLT's applications in dentistry, focusing on its mechanisms of action and biological effects, and emphasizes the uniqueness of LLLT as a transformative tool in modern dental care.

Circulating tumor DNA association with residual cancer burden after neoadjuvant chemotherapy in triple-negative breast cancer in TBCRC 030

BACKGROUND

We aimed to examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy.

PATIENTS AND METHODS

We identified responders (RCB 0/1) and matched non-responders (RCB 2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel versus cisplatin in TNBC. We collected plasma samples at baseline, 3 weeks and 12 weeks (end of therapy). We created personalized ctDNA assays utilizing MAESTRO mutation enrichment sequencing. We explored associations between ctDNA and RCB status and disease recurrence.

RESULTS

Of 139 patients, 68 had complete samples and no additional neoadjuvant chemotherapy. Twenty-two were responders and 19 of those had sufficient tissue for whole-genome sequencing. We identified an additional 19 non-responders for a matched case-control analysis of 38 patients using a MAESTRO ctDNA assay tracking 319-1000 variants (median 1000 variants) to 114 plasma samples from 3 timepoints. Overall, ctDNA positivity was 100% at baseline, 79% at week 3 and 55% at week 12. Median tumor fraction (TFx) was 3.7 × 10-4 (range 7.9 × 10-7-4.9 × 10-1). TFx decreased 285-fold from baseline to week 3 in responders and 24-fold in non-responders. Week 12 ctDNA clearance correlated with RCB: clearance was observed in 10 of 11 patients with RCB 0, 3 of 8 with RCB 1, 4 of 15 with RCB 2 and 0 of 4 with RCB 3. Among six patients with known recurrence, five had persistent ctDNA at week 12.

CONCLUSIONS

Neoadjuvant chemotherapy for TNBC reduced ctDNA TFx by 285-fold in responders and 24-fold in non-responders. In 58% (22/38) of patients, ctDNA TFx dropped below the detection level of a commercially available test, emphasizing the need for sensitive tests. Additional studies will determine whether ctDNA-guided approaches can improve outcomes.

Examining the Impact of Preheating on the Fracture Toughness and Microhardness of Composite Resin: A Systematic Review

The objective of this comprehensive study was to systematically evaluate the effects of preheating on two critical mechanical properties, microhardness and fracture toughness, in resin composite materials. The overarching goal was to provide valuable insights into the potential benefits and limitations of this technique for enhancing the overall mechanical performance of such materials. To achieve this, an extensive and systematic electronic search was conducted across multiple reputable databases, including MEDLINE/PubMed, SCOPUS, ProQuest, SpringerLink, Web of Science, ScienceDirect, and Google Scholar, with data collection extending until June 2023. This rigorous search process resulted in the identification of 29 pertinent articles, which were subjected to a thorough risk of bias assessment employing the Quality Assessment Tool For In Vitro Studies (QUIN). The findings of this comprehensive investigation revealed several noteworthy trends. First, concerning microhardness, all the studies consistently demonstrated a positive effect of preheating on this mechanical property. This uniformity in results corroborates the initial hypothesis that preheating indeed enhances microhardness in resin composite materials. Second, with respect to fracture toughness, a majority of the studies provided evidence supporting the notion that preheating has a favorable influence on this particular mechanical property. This alignment of outcomes suggests that preheating can be a beneficial technique for improving fracture toughness in resin composites. However, it is essential to note that there were a few exceptions within the collected data, where preheating appeared to lead to a decrease in fracture toughness. Additionally, one study reported no statistically significant effect on fracture toughness. These deviations from the general trend highlight the complexity of the relationship between preheating and fracture toughness, indicating that other factors or material-specific nuances may come into play. In conclusion, the results of this study indicate that preheating resin composites can improve microhardness and fracture toughness, offering potential benefits for dental restorations. Yet, conflicting data warrants further research to uncover the reasons behind these discrepancies. Future studies should also investigate preheating's broader impact on composite resin materials to gain a comprehensive understanding of its applications and limitations in the field.

Glutaredoxin proteins from E. coli isoforms were compared in terms of energy frustration

Glutaredoxin (GRXs) protein plays a vital role inside the cell, including redox control of transcription to the cell's antioxidant defense, apoptosis, and cellular differentiation regulation. In this study, we have investigated the energy landscape and characterized the pattern of local frustration in different forms and states of the GRX protein ofE. coli.Analysis was done on the conformational alterations, significant changes in the frustration pattern, and different GRXs such as GRX-II, GRX-III, GRX-II-GSH, and GRX-III-GSH complex. We have found the practice of frustration, and structure was quite similar in the same isoform having different states of protein; however, a significant difference was observed between different isoforms. Moreover, oxidation of GRX-I introduced an extra α-helix increasing the destabilizing interactions within the protein. The study of frustrated contacts on oxidized and reduced GRX and with bound and unbound Glutathione indicates its potential application in activating and regulating the behavior of GRXs.

Management of Discoloured Anterior Teeth With Radicular Cyst: A Case Report

Dental trauma often has tooth discoloration and periapical lesion as its sequelae. Intracoronal bleaching restores the aesthetics, while a retrograde approach is required for non-healing lesions. A patient with discolored teeth, draining sinus, tenderness and a periapical lesion on the radiograph was treated initially with conventional root canal therapy and walking bleach technique. After four months, the sinus tract reappeared and on cone-beam computed tomography (CBCT) examination, a large periapical lesion with loss of buccal cortical plate was seen. A minimally invasive retrograde cystic enucleation, apicectomy, and filling with biodentine were then performed. The defect area was filled with synthetic nanocrystalline hydroxyapatite granules combined with platelet-rich-fibrin. Follow-ups after one, three, and six months were taken. The six-month CBCT revealed complete bone healing. Non-vital bleaching yields acceptable cosmetic results. Additionally, if the conventional procedures are not successful in treating radicular cyst, apical surgery must be the ultimate choice.

Comparison of Composite Resin (Duo-Shade) Shade Guide with Vita Ceramic Shades Before and After Chemical and Autoclave Sterilization

BACKGROUND This study aimed to compare a composite resin (Duo-Shade) shade guide with Vita ceramic shades before/after chemical and autoclave sterilization. MATERIAL AND METHODS Color values (L*a*b*) were recorded directly from shade tabs of prefabricated composite resin (Brilliant NG Universal Duo-Shade) and ceramic (Vita classic) shade guide with a calibrated spectrophotometer (Vita Easy Shade Advance 4.0). Seventy-two composite resin disk samples with 6 different shades (A1/B1, A2/B2, A3/D3, A3.5/B3, A4/C4, and C2/C3) (n=12 each) were divided into 2 groups (Gp) - Gp A (Autoclave) and Gp C (Chemical) (15 cycles) - to assess their influence on respective shades. Mean values calculated the color differences (ΔE) while differences in color values (L*a*b*) were graded on the National Bureau of Standards (NBS) 6-grade scale and assessed for Clinical Acceptance/Perceptible Threshold (CAT), (CPT). All differences were considered significant if the color difference ΔE was ≥3.3. RESULTS Only 2 out of 12 Shade tabs (C2C3, A4C4) of composite resin matched to Vita shade tab C2 and C4 (ΔE ≤3.3). Both groups showed notable color differences after respective sterilization protocols, with color differences in Gp A significantly higher than Gp C (DE ³3.3). Within groups, all shades in Gp A showed remarkably different color changes, with shade C2C3 and A1B1 being denoted as clinically unacceptable. CONCLUSIONS Manufacturer-provided shade guides do not match ceramic shades as claimed and chemical sterilization using 10% Deconex was associated with less color changes than with autoclave sterilization.

Evaluation of the impact of continuous Kangaroo Mother Care (KMC) initiated immediately after birth compared to KMC initiated after stabilization in newborns with birth weight 1.0 to < 1.8 kg on neurodevelopmental outcomes: Protocol for a follow-up study

BACKGROUND

Preterm birth or low birth weight is the single largest cause of death in newborns, however this mortality can be reduced through newborn care interventions, including Kangaroo Mother Care (KMC). Previously, a multi-country randomized controlled trial, coordinated by the World Health Organization (WHO), reported a significant survival advantage with initiation of continuous KMC immediately after birth compared with initiation of continuous KMC a few days after birth when the baby is considered clinically stable. Whether the survival advantage would lead to higher rates of neurodevelopmental morbidities, or the immediate KMC will also have a beneficial effect on cognitive development also, has not been investigated. We therefore propose to test the hypothesis that low-birth-weight infants exposed to immediate KMC will have lower rates of neurodevelopmental impairment in comparison to traditional KMC-treated infants, by prospectively following up infants already enrolled in the immediate KMC trial for the first 2 years of life, and assessing their growth and neurodevelopment.

METHODS

This prospective cohort study will enroll surviving neonates from the main WHO immediate KMC trial. The main trial as well as this follow-up study are being conducted in five low- and middle-income countries in South Asia and sub-Saharan Africa. The estimated sample size for comparison of the risk of neurodevelopmental impairment is a total of 2200 children. The primary outcome will include rates of cerebral palsy, hearing impairment, vision impairment, mental and motor development, and epilepsy and will be assessed by the age of 3 years. The analysis will be by intention to treat.

DISCUSSION

Immediate KMC can potentially reduce low-birth-weight-associated complications such as respiratory disease, hypothermia, hypoglycemia, and infection that can result in impaired neurocognitive development. Neuroprotection may also be mediated by improved physiological stabilization that may lead to better maturation of neural pathways, reduced risk of hypoxia, positive parental impact, improved sleep cycles, and improved stress responses. The present study will help in evaluating the overall impact of KMC by investigating the long-term effect on neurodevelopmental impairment in the survivors.

TRIAL REGISTRATION

Clinical Trials Registry-India CTRI/2019/11/021899. Registered on 06 November 2019. Trials registration of parent trial: ACTRN12618001880235; Clinical Trials Registry-India: CTRI/2018/08/015369.

Closed-loop optogenetic control of the dynamics of neural activity in non-human primates

Electrical neurostimulation is effective in the treatment of neurological disorders, but associated recording artefacts generally limit its applications to open-loop stimuli. Real-time and continuous closed-loop control of brain activity can, however, be achieved by pairing concurrent electrical recordings and optogenetics. Here we show that closed-loop optogenetic stimulation with excitatory opsins enables the precise manipulation of neural dynamics in brain slices from transgenic mice and in anaesthetized non-human primates. The approach generates oscillations in quiescent tissue, enhances or suppresses endogenous patterns in active tissue and modulates seizure-like bursts elicited by the convulsant 4-aminopyridine. A nonlinear model of the phase-dependent effects of optical stimulation reproduced the modulation of cycles of local-field potentials associated with seizure oscillations, as evidenced by the systematic changes in the variability and entropy of the phase-space trajectories of seizures, which correlated with changes in their duration and intensity. We also show that closed-loop optogenetic neurostimulation could be delivered using intracortical optrodes incorporating light-emitting diodes. Closed-loop optogenetic approaches may be translatable to therapeutic applications in humans.

Anterior Matrix Systems for Composite Restorations: A Review

In the field of restorative dentistry, composite resins have emerged as the most utilized materials. They revolutionized the cosmetic approach to anterior tooth treatment since their introduction to dental practice. In cases where one or more of the tooth's walls are absent, matrices are employed to assist in the creation of the proper anatomic contour and proximal contacts without the occurrence of gingival overhangs. Matrices come in a variety of designs suitable for various therapeutic conditions. Depending on the level of tooth destruction, they might range from a simple metal or plastic strip to a circumferential ring of metal surrounding the entire crown. Although the handling characteristics of modern composites have significantly improved, dentists still encounter challenges with the development of good interproximal contact and proper anatomical contour. The utilization of an anterior matrix system can be paramount in achieving these objectives.

Characterization of paddy-residue burning derived carbonaceous aerosols using dual carbon isotopes

A large scale paddy-residue burning (PRB) happens every year in the northwest Indo-Gangetic Plain (IGP) during the post-monsoon season, and winds transport pollutants from the source region up to the northern Indian Ocean affecting air quality of the IGP and marine region. In this study, day-night pairs of fine aerosol samples (n = 69) were collected during October-November over Patiala (30.2°N, 76.3°E, 250 m amsl), a site located in the source region of PRB. Carbonaceous aerosols (CA) were characterised using chemical species and dual carbon isotopes (¹³C and ¹⁴C) to estimate bio vs non-bio contributions and understand their characteristics. Percentage of bio fraction (f_bio, estimated using ¹⁴C) in CA varied from 74 % to 87 % (avg: 80 ± 3) during days and 71 % to 96 % (avg: 85 ± 7 %) during nights. Further, the f_bio was found to be better correlated with aerosol mass spectrometer derived f60 compare to levoglucosan (LG) or nssK⁺, suggesting f60 a useful proxy for PRB. The δ¹³C varied from -27.7 ‰ to -26.0 ‰ (avg: -27.0 ± 0.4 ‰) and - 28.7 ‰ to -26.4 ‰ (avg: -27.5 ± 0.7 ‰) during day and night, respectively. Measured δ¹³C of the samples was found to be more enriched than expected by 0.3 to 2.0 ‰, indicating the presence of aged CA also in Patiala even during PRB period. From f_bio versus δ¹³C correlation, and from Miller-Trans plot, δ¹³C of PRB is found to be -28.9 ± 1.1 ‰, which also infers that Miller-Trans plot can be used to understand source isotopic signature in the absence of radiocarbon measurements in aerosols. Further, the characteristics ratios of organic carbon (OC) to elemental carbon (EC) (11.9 ± 4.1), LG to potassium (K⁺) (0.84 ± 0.15), OC/LG (19.7 ± 2.0) and K⁺/EC (0.75 ± 0.27) were calculated by considering samples with f_bio higher than 0.90, which can be used for source apportionment studies. Such studies are crucial in assessing the effects of PRB on regional air quality and climate.

A213 UNDERSTANDING PATIENT AND PHYSICIAN ATTITUDES AND EXPECTATIONS REGARDING IDENTIFYING AND MANAGING ANXIETY AND DEPRESSION IN IBD

Background

Patients living with Inflammatory Bowel Disease (IBD) commonly experience a number of mental health-related challenges, specifically anxiety and mood disorders (AMDs). Although there has been an awareness of the relationship between IBD and AMD within the GI research and clinical space; detection, treatment, and management amongst care providers is limited. Therefore, we are seeking to explore the overall experiences of patients living with Inflammatory Bowel Disease to identify and evaluate their experiences in interactions with GI clinicians around mental health in diverse care settings in order to determine how to best support mental health care amongst IBD patients.

Purpose

We aimed to explore perspectives, experiences and barriers to engaging with mental health-related challenges amongst IBD patients when interacting with gastroenterologists over the course of their health journey.

Method

We conducted 5 semi-structured online focus groups co-facilitated by patient researchers in early 2020 through Zoom which spanned for a total of 2.5 hours each. Participants were recruited through social media channels, GI clinics, the IMAGINE-SPOR unit, and Crohn’s and Colitis Canada. A semi-structured interview guide was developed for patient researchers to follow during the focus groups which provided guided questions that would allow patient participants to explore and reflect on: their experiences living with IBD, their expectations around mental health support, their perception of the engagement of GIs in mental health discussions, and their expectations for mental health support and services moving forward. Audio recordings from the semi-structured focus groups were then transcribed and thematic analysis was used to identify emerging themes and patient expectations.

Result(s)

We identified the following key themes: 1) experiences with IBD: difficulties related to reintegrating into social settings, feelings of loneliness; 2) expectations around mental health support: the need to develop their own resiliency strategies due to the lack of structural resources regarding mental health and IBD in the clinical space; 3) GI engagement: HCPs were dismissive of mental health symptoms, often gaslighting patients when mentioning mental health concerns during clinical encounters; and 4) expectations: a need to standardize mental health care across IBD care practice with a focus on potentially integrating healthcare providers of diverse care settings to help address the need for mental health support in such a vast patient population.

Conclusion(s)

Our study suggests that effective detection, management and awareness, along with the integration of feedback from patient lived experiences can help inform the development of mental health support and services which cater to the needs of people living with IBD. Results from this study will be interpreted in line with insight gathered from upcoming interviews of gastroenterologists and HCPs.

Please acknowledge all funding agencies by checking the applicable boxes below

CIHR, Other

Please indicate your source of funding;

IMAGINE SPOR INCUBATOR Grant

Disclosure of Interest

None Declared

Development and validation of a risk score (Delay-7) to predict the occurrence of a treatment delay following cycle 1 chemotherapy

BACKGROUND

The risk of toxicity-related dose delays, with cancer treatment, should be included as part of pretreatment education and be considered by clinicians upon prescribing chemotherapy. An objective measure of individual risk could influence clinical decisions, such as escalation of standard supportive care and stratification of some patients, to receive proactive toxicity monitoring.

PATIENTS AND METHODS

We developed a logistic regression prediction model (Delay-7) to assess the overall risk of a chemotherapy dose delay of 7 days for patients receiving first-line treatments for breast, colorectal and diffuse large B-cell lymphoma. Delay-7 included hospital treated, age at the start of chemotherapy, gender, ethnicity, body mass index, cancer diagnosis, chemotherapy regimen, colony stimulating factor use, first cycle dose modifications and baseline blood values. Baseline blood values included neutrophils, platelets, haemoglobin, creatinine and bilirubin. Shrinkage was used to adjust for overoptimism of predictor effects. For internal validation (of the full models in the development data) we computed the ability of the models to discriminate between those with and without poor outcomes (c-statistic), and the agreement between predicted and observed risk (calibration slope). Net benefit was used to understand the risk thresholds where the model would perform better than the 'treat all' or 'treat none' strategies.

RESULTS

A total of 4604 patients were included in our study of whom 628 (13.6%) incurred a 7-day delay to the second cycle of chemotherapy. Delay-7 showed good discrimination and calibration, with c-statistic of 0.68 (95% confidence interval 0.66-0.7), following internal validation and calibration-in-the-large of -0.006.

CONCLUSIONS

Delay-7 predicts a patient's individualised risk of a treatment-related delay at cycle two of treatment. The score can be used to stratify interventions to reduce the occurrence of treatment-related toxicity.

1362 ANTICHOLINERGIC PRESCRIBING HABITS AND ITS ASSOCIATIONS IN A COMMUNITY POPULATION OF PEOPLE LIVING WITH DEMENTIA

Introduction

Many commonly prescribed medications have inadvertent anticholinergic effects. People with Dementia (PwD) are more vulnerable to these effects and at risk of adverse outcomes, the risk being higher with a greater degree of anticholinergic exposure. We investigated prescribing patterns and Anticholinergic burden (ACB) in a cohort of community-dwelling older adults with dementia and aimed to explore the effect of ACB on cognition, mood, and quality of life(QoL).

Method

The medication and demographic information for 87 (39 female) community-dwelling PwD were obtained from Electronic Care Summaries. We used the German Anticholinergic Burden Scale (GABS) to measure ACB. Additionally, we investigated associations between ACB and cognitive (ADAS-Cog), functional (BADL) and QoL (DemQoL) assessments.

Results

28.7% of participants had a clinically significant score (ACB&gt; 2). The most commonly prescribed medications with ACB were Lansoprazole(18.3%), Mirtazapine(12.6%) and Codeine(12.6%). ACB was higher in males and negatively correlated with age, r(87)=-.21,p=.03. There was no association between ACB and cognition, QoL, functional independence, and neuropsychiatric symptoms. Over six months, PLWD with no ACB had a greater negative change in neuropsychiatric symptoms[t(18)=2.27,p=.04] and functional independence[t(23)=-3.8,p=.001], indicating greater dependence and worsening neuropsychiatric symptoms.

Conclusion

A third of PLWD in the community had clinically significant ACB. No ACB was associated with worsening neuropsychiatric symptoms and functional dependence over a six-month period. Community prescribers should consider regular medication reviews with PLWD and carers to ensure medications are prescribed safely and appropriately.

Validating low-fidelity arthroscopic simulation in medical students: a feasibility trial

INTRODUCTION

With surgical opportunities becoming increasingly restricted for orthopaedic trainees, simulation training is a valuable alternative at providing sufficient practice. This pilot study aims to assess the potential effectiveness of low-fidelity simulation in teaching medical students basic arthroscopic skills and the feasibility of its incorporation into formal student training programmes.

METHODS

Twenty-two medical students completed pre- and post-training tests on the Probing (Task 1) and Maze (Task 2) exercises from the Sawbones 'Fundamentals of Arthroscopy Surgery Training' (FAST) programme. Training consisted of practising horizon control, deliberate linear motion and probing within 25min over a period of days. Completion time and error frequency were measured. The difference in performance was assessed using a paired two-tailed t-test. Qualitative data were collected.

RESULTS

Test completion time decreased significantly by a mean of 83s (±46s, 95% confidence intervals [CI] 37 to 129) for Task 1 (p=0.001) and 105s (±55s, 95% CI 50 to 160) for Task 2 (p=0.0007). Frequency of direct visualisation errors decreased significantly by a mean of 1.0 errors (±1.0 errors, 95% CI 0.1 to 2.0) for Task 1 (p = 0.04) and 0.8 errors (±0.8 errors, 95% CI 0.1 to 1.6) for Task 2 (p = 0.04). At post-training, 82% of participants were willing to incorporate FAST into formal training.

CONCLUSIONS

Low-fidelity simulators such as FAST can potentially teach basic arthroscopic skills to medical students and are feasible for incorporation into formal training. They also give students a cost-effective and safe basic surgical training experience.

Metal nanoparticles produced by plants with antibacterial properties against Staphylococcus aureus

Staphylococcus aureus (S. aureus) is a pathogenic bacteria that causes a variety of potentially fatal infections. The emergence of antibiotic-resistant strains of S. aureus has made treatment even more difficult. In recent years, nanoparticles have been used as an alternative therapeutic agent for S. aureus infections. Among various methods for the synthesis of nanoparticles, the method utilizing plant extracts from different parts of a plant, such as root, stem, leaf, flower, seeds, etc. is gaining widespread usage. Phytochemicals present in plant extract are an inexpensive, eco-friendly, natural material that act as reducing and stabilization agent for the nanoparticle synthesis. The utilization of plant-fabricated nanoparticles against S. aureus is currently in trend. The current review discusses recent findings in the therapeutic application of phytofabricated metal-based nanoparticles against Staphylococcus aureus.

Cytosolic aldose metabolism contributes to progression from cirrhosis to hepatocarcinogenesis

Oxidative stress modulates carcinogenesis in the liver; however, direct evidence for metabolic control of oxidative stress during pathogenesis, particularly, of progression from cirrhosis to hepatocellular carcinoma (HCC), has been lacking. Deficiency of transaldolase (TAL), a rate-limiting enzyme of the non-oxidative branch of the pentose phosphate pathway (PPP), restricts growth and predisposes to cirrhosis and HCC in mice and humans. Here, we show that mitochondrial oxidative stress and progression from cirrhosis to HCC and acetaminophen-induced liver necrosis are critically dependent on NADPH depletion and polyol buildup by aldose reductase (AR), while this enzyme protects from carbon trapping in the PPP and growth restriction in TAL deficiency. Both TAL and AR are confined to the cytosol; however, their inactivation distorts mitochondrial redox homeostasis in opposite directions. The results suggest that AR acts as a rheostat of carbon recycling and NADPH output of the PPP with broad implications for disease progression from cirrhosis to HCC.

Utility of sirolimus coated balloons in the peripheral vasculature – a review of the current literature

Sirolimus-coated balloons (SCB) have demonstrated much promise as an alternative drug eluting device to the existing paclitaxel coated balloon platforms for the treatment of peripheral arterial disease (PAD). They have been well tested pre-clinically and have demonstrated anti-restenotic effects as well as clinical safety in its use for treatment of coronary artery disease. The existing approved SCBs have thus far demonstrated good short-term patency (12-months) and did not exhibit any major adverse events or device related shortcomings in its use for treatment of PAD. There are several studies ongoing which aim to further investigate the efficacy of existing SCBs and establish a direct comparison of its outcomes compared with plain balloon angioplasty. Also, SCB utility to salvage failing arteriovenous fistulas for haemodialysis patients has also been explored. We review the current progress made in the establishment of SCB in the treatment of PAD as well as highlight ongoing studies investigating the role of SCB in various settings.