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The need for improved wet adhesives has driven research on mussel-inspired materials incorporating dihydroxyphenylalanine (DOPA) and related analogs of the parent catechol, but their susceptibility to oxidation limits practical application of these functionalities. Here, we investigate the molecular-level adhesion of the catechol analogs dihydroxybenzamide (DHB) and hydroxypyridinone (HOPO) as a function of pH. We find that the molecular structure of the catechol analogs influences their susceptibility to oxidation in alkaline conditions, with HOPO emerging as a particularly promising candidate for pH-tolerant adhesives for diverse environmental conditions.

We theoretically investigate the ability to design optical filters from a single material and a single layer of randomly dispersed resonant dielectric particles, defining a random metasurface. Using a Bayesian and generalized Mie inverse-design approach, we design particle radii distributions that give rise to longpass, shortpass, bandpass, and bandstop spectral bands in the infrared. The optical response is shown to be directly related to electric and magnetic multipole scattering of the constituent particles and their near field coupling. We discuss the effect of the particle size distribution and particle–particle coupling interactions on filter design in random systems lacking long-range order.

Yohei Tanaka,1 Richard Parker,2 Amaryllis Aganahi2 1Clinica Tanaka Plastic, Reconstructive Surgery and Anti-Aging Center, Matsumoto, Nagano, Japan; 2RATIONALE, Kyneton, VIC, AustraliaCorrespondence: Yohei Tanaka, Clinica Tanaka Plastic, Reconstructive Surgery and Anti-aging Center, M-1 Bld 1F, 3-4-3, Ote, Matsumoto, Nagano, 390-0874, Japan, Tel +81-263-36-0016, Fax +81-263-36-0016, Email info@clinicatanaka.jpBackground: Clinical, optical and histological research confirms that solar skin damage continues to pose a threat to human skin health globally despite widespread sunscreen usage and sun awareness campaigns. Despite this, very few studies examine the critical changes in gene expression and DNA repair activity following recommended topical solar protection and repair strategies to ameliorate the harmful effects of ultraviolet, visible light and near-infrared radiation.Purpose: To investigate alterations in gene expression following topical solar protection and solar repair strategies.Methods: Using epidermal keratinocytes and dermal fibroblasts derived from a 3-dimensional reconstructed human skin model, gene expression was assessed via the Genemarkers Standard Skin Panel using 112 genes deploying two analytical techniques: DNA microarray and quantitative real-time PCR exploration. Tissues were inoculated with products then collected after 24 hours following application of solar protection formulations and 16 hours following solar repair formulations (The Essential Six, RATIONALE, Victoria, Australia).Results: A DNA microarray revealed 67 genes that were significantly up-regulated or down-regulated following the treatment. The quantitative real-time PCR revealed that, in comparison to the control, the genes encoding Intercellular Adhesion Molecule 1 (ICAM1), Metallothionein 1A (MT1A), Prostaglandin-Endoperoxide Synthase 1 (PTGS2), Late Cornified Envelope 3D (LCE3D), Peroxisome Proliferator Activated Receptor (PPARD), and Granulocyte/Macrophage Colony Stimulating Factor 2 (GM-CSF2) have been up-regulated following usage of the solar protection regime, 1.87, 861.16, 4.34, 1.91, 1.06, and 3.6, respectively. ICAM1, MT1A, PTGS2, LCE3D, PPARD, and GM-CSF2 were up-regulated following use of the solar repair regime, 3.78, 2.98, 14.89, 5.09, 2.42, and 13.51, respectively.Conclusion: This study demonstrates that a specific solar protection and repair regime upregulated genes involved in photoprotection and repair mechanisms in a 3-dimensional (3D) reconstructed human-like skin model.Keywords: gene expression, anti-photoageing, anti-photoimmunosuppression, antioxidant, photoprotection, DNA repair

Ferric complexes of triscatechol siderophores may assume one of two enantiomeric configurations at the iron site. Chirality is known to be important in the iron uptake process, however an understanding of the molecular features directing stereospecific coordination remains ambiguous. Synthesis of the full suite of (DHBL/DLysL/DSer)3 macrolactone diastereomers, which includes the siderophore cyclic trichrysobactin (CTC), enables the effects that the chirality of Lys and Ser residues exert on the configuration of the Fe(iii) complex to be defined. Computationally optimized geometries indicate that the Λ/Δ configurational preferences are set by steric interactions between the Lys sidechains and the peptide backbone. The ability of each (DHBL/DLysL/DSer)3 diastereomer to form a stable Fe(iii) complex prompted a genomic search for biosynthetic gene clusters (BGCs) encoding the synthesis of these diastereomers in microbes. The genome of the plant pathogen Dickeya chrysanthemi EC16 was sequenced and the genes responsible for the biosynthesis of CTC were identified. A related but distinct BGC was identified in the genome of the opportunistic pathogen Yersinia frederiksenii ATCC 33641; isolation of the siderophore from Y. frederiksenii ATCC 33641, named frederiksenibactin (FSB), revealed the triscatechol oligoester, linear-(DHBLLysLSer)3. Circular dichroism (CD) spectroscopy establishes that Fe(iii)-CTC and Fe(iii)-FSB are formed in opposite enantiomeric configuration, consistent with the results of the ferric complexes of the cyclic (DHBL/DLysL/DSer)3 diastereomers.

Ferric complexes of triscatechol siderophores may assume one of two enantiomeric configurations at the iron site. Chirality is known to be important in the iron uptake process, however an understanding of the molecular features directing stereospecific coordination remains ambiguous. Synthesis of the full suite of (DHBL/DLysL/DSer)3 macrolactone diastereomers, which includes the siderophore cyclic trichrysobactin (CTC), enables the effects that the chirality of Lys and Ser residues exert on the configuration of the Fe(iii) complex to be defined. Computationally optimized geometries indicate that the Λ/Δ configurational preferences are set by steric interactions between the Lys sidechains and the peptide backbone. The ability of each (DHBL/DLysL/DSer)3 diastereomer to form a stable Fe(iii) complex prompted a genomic search for biosynthetic gene clusters (BGCs) encoding the synthesis of these diastereomers in microbes. The genome of the plant pathogen Dickeya chrysanthemi EC16 was sequenced and the genes responsible for the biosynthesis of CTC were identified. A related but distinct BGC was identified in the genome of the opportunistic pathogen Yersinia frederiksenii ATCC 33641; isolation of the siderophore from Y. frederiksenii ATCC 33641, named frederiksenibactin (FSB), revealed the triscatechol oligoester, linear-(DHBLLysLSer)3. Circular dichroism (CD) spectroscopy establishes that Fe(iii)-CTC and Fe(iii)-FSB are formed in opposite enantiomeric configuration, consistent with the results of the ferric complexes of the cyclic (DHBL/DLysL/DSer)3 diastereomers.

5'10'. DARK HAIR. Gentle and easygoing. At the time of his death, in the '60s, they said he had schizophrenia, but the diagnosis today likely would be a developmental disability, [...]

BACKGROUND: Immersive, realistic, and low-risk training has long been ideal for skill-based disciplines such as surgery. Recent advances in virtual reality technology have led to development of surgical training software with the goal to provide experience without risk. The aim of this review is to summarize the current data for virtual reality-based orthopaedic surgery training to evaluate how beneficial the technology may become in educational circumstances. METHODS: A literature review was completed analyzing eight randomized controlled trials completed between 2019 to 2022 to evaluate the effect of virtual reality on orthopaedic surgery education for medical students and residents. Each trial included groups of learners that were trained on a specific procedure with standard methods (“control”) or virtual reality software (“VR group”). Subjects were then evaluated on completion of procedures with real-life models. Procedures included total hip arthroplasty (n=2), tibial intramedullary nail (n=2), slipped capital femoral epiphysis pinning (n=2), and unicompartmental knee arthroplasty (n=2). The primary metrics assessed were time to complete procedure and objective assessment scores. Secondarily survey results were evaluated regarding subjects’ perceived utility of virtual reality in orthopaedic surgery training. RESULTS: 168 subjects (medical students n=68, residents n=100) were included across the 8 different trials. All trials included at least one objective assessment and it was found that overall, the VR group performed 19.9% better than control group on average (19.875 ± 18.324, 95% CI). Seven of the trials reported time to complete procedure, in which it was found that overall VR group completed the procedures 12% faster than control group on average (12 ± 10.988, 95% CI). Subjective measures showed that over 70% of subjects found the VR learning to be at least “helpful” or “useful”. CONCLUSION: Early studies of the emerging field of virtual reality in surgical training are promising. When looking at objective measures and time to complete procedures, VR trained learners perform as well, if not better, than standard method learners. Inclusion of virtual reality-based practice in medical school curricula and residency training may lead to less surgical errors, increased knowledge of procedures, and more efficient learning in real-life scenarios. This potential impact extends beyond well-resourced institutions, as VR technology can provide a cost-effective and accessible alternative for surgical training in low-income and low-resource areas of the world, democratizing access to high-quality medical education. Continued research on translation into clinical practice is warranted, with the potential to bridge educational disparities and improve surgical outcomes on a global scale.

We conducted a Cochrane systematic review on the effectiveness of supplemental intravenous crystalloid administration in preventing postoperative nausea and vomiting. We included randomised controlled trials of patients undergoing surgery under general anaesthesia and given supplemental peri-operative intravenous crystalloid. Our primary outcomes were the risk of postoperative nausea and the risk of postoperative vomiting. We assessed the risk of bias for each included study and applied the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework for the certainty of evidence. We included 41 studies. We found that the intervention probably reduces the overall risk of postoperative nausea, the risk ratio (95%CI) being 0.62 (0.51-0.75) (I2  = 57%, p

Progressive iron accumulation and renal impairment are prominent in both patients and mouse models of sickle cell disease (SCD). Endothelin A receptor (ETA) antagonism prevents this iron accumulation phenotype and reduces renal iron deposition in the proximal tubules of SCD mice. To better understand the mechanisms of iron metabolism in the kidney and the role of the [ET.sub.A] receptor in iron chelation and transport, we studied renal iron handling in a nonsickle cell iron overload model, heme oxygenase-1 ([Hmox-1.sup.-/-]) knockout mice. We found that [Hmox-1.sup.-/-] mice had elevated plasma endothelin-1 (ET-1), cortical ET-1 mRNA expression, and renal iron content compared with [Hmox-1.sup.+/+] controls. The [ET.sub.A] receptor antagonist, ambrisentan, attenuated renal iron deposition, without any changes to anemia status in Hmox-1mice. This was accompanied by reduced urinary iron excretion. Finally, ambrisentan had an important iron recycling effect by increasing the expression of the cellular iron exporter, ferroportin-1 (FPN-1), and circulating total iron levels in [Hmox-1.sup.-/-] mice. These findings suggest that the ET-1/[ET.sub.A] signaling pathway contributes to renal iron trafficking in a murine model of iron overload. Keywords: endothelin-1, iron homeostasis, ferroportin-1, sickle cell disease L'accumulation progressive de fer et l'insuffisance renale progressive se retrouvent de maniere proeminente chez les patients atteints d'anemie falciforme (AF) comme dans les modeles de la maladie chez la souris. L'antagonisme des recepteurs de l'endotheline A (ETA) permet de prevenir ce phenotype d'accumulation de fer et d'attenuer le depot de fer au niveau des tubules proximaux des reins de souris AF. Afin de mieux comprendre les modes d'action du metabolisme du fer dans les reins et le role des recepteurs [ET.sub.A] dans la chelation et le transport du fer, nous avons etudie la gestion du fer renal dans un modele de surcharge en fer sans AF : la souris << knock-out >> heme oxygenase 1 ([Hmox-1.sup.-/-]). Nous avons observe que la souris [Hmox-1.sup.-/-] presentait des taux plasmatiques d'endotheline 1 (ET-1), une expression corticale d'ET-1 en ARNm et des taux de fer dans les reins plus eleves que les temoins [Hmox-1.sup.+/+]. L'ambrisentane, un antagoniste des recepteurs ETA, permettait d'attenuer le depot de fer dans les reins sans aucune modification de l'etat anemique des souris [Hmox-1.sup.-/-], ce qui s'accompagnait d'une diminution de l'excretion urinaire du fer. Enfin, l'ambrisentane avait un important effet de recyclage du fer par l'entrainement d'un accroissement de l'expression de la ferroportine 1 (FPN-1), un exportateur de fer cellulaire, de meme que des taux de fer en circulation chez les souris [Hmox-1.sup.-/-]. Ces resultats laissent entendre que la voie de signalisation ET-1/ETA participerait au trafic du fer renal dans un modele de surcharge en fer chez la souris. Mots-cles : endotheline-1, homeostasie du fer, ferroportine 1, anemie falciforme, Introduction Iron homeostasis is fundamental for physiological processes in the body, and its imbalance has severe health consequences. Thus, iron metabolism is tightly regulated at the systemic and cellular levels. [...]

Marine mussels secrete proteins rich in residues containing catechols and cationic amines that displace hydration layers and adhere to charged surfaces under water via a cooperative binding effect known as catechol-cation synergy. Mussel-inspired adhesives containing paired catechol and cationic functionalities are a promising class of materials for biomedical applications, but few studies address the molecular adhesion mechanism(s) of these materials. To determine whether intramolecular adjacency of these functionalities is necessary for robust adhesion, a suite of siderophore analog surface primers was synthesized with systematic variations in intramolecular spacing between catechol and cationic functionalities. Adhesion measurements conducted with a surface forces apparatus (SFA) allow adhesive failure to be distinguished from cohesive failure and show that the failure mode depends critically on the siderophore analog adsorption density. The adhesion of these molecules to muscovite mica in an aqueous electrolyte solution demonstrates that direct intramolecular adjacency of catechol and cationic functionalities is not necessary for synergistic binding. However, we show that increasing the catechol-cation spacing by incorporating nonbinding domains results in decreased adhesion, which we attribute to a decrease in the density of catechol functionalities. A mechanism for catechol-cation synergy is proposed based on electrostatically driven adsorption and subsequent binding of catechol functionalities. This work should guide the design of new adhesives for binding to charged surfaces in saline environments.

Background: Breast cancer is a common condition, and the number of cases is projected to increase 52% between 2012 and 2030. Care of breast cancer patients occurs along an interdisciplinary continuum involving family physicians, general surgeons, radiologists, pathologists, medical oncologists, radiation oncologists, and allied health workers. There are national benchmarks for wait times between each step from diagnosis to treatment. In this quality improvement project, we sought to measure these wait times at our hospital by comparing results for 2013 and 2023, identifying causes of delays, and proposing solutions to reduce wait times. Methods: We included all patients who were diagnosed with breast malignancies and referred to the general surgery service at Vernon Jubilee Hospital in 2013 and 2023. Results were analyzed using the two-tailed t test and Fisher exact test for continuous and categorical variables, respectively. A P value less than .05 was considered significant. Results: The number of patients increased from 69 in 2013 to 113 in 2023. Mean wait times from initial imaging referral to surgery increased from 67 to 114 days (P < .01) during this period. Mean wait times from imaging referral to pathology diagnosis increased from 36 to 71 days (P < .01), due primarily to an increase from 34 to 80 days for symptomatic patients who were referred by their family physician (P < .01); wait times for asymptomatic patients who were identified by the Screening Mammography Program increased from 40 to 58 days (P = .09). Mean wait times from biopsy to final biomarker report (ER/PR/HER2) increased from 25 days to 29 days (P = .25), from surgery to final pathology increased from 11 to 17 days (P < .01), from surgical consultation to surgery increased from 17 to 31 days (P < .01), from referral to medical oncology consultation increased from 14 to 30 days (P < .01), and from referral to radiation oncology consultation increased from 78 to 106 days (P = .025). Most wait times met benchmark wait times in 2013 but failed to meet them in 2023. Conclusions: Wait times increased at every stage of the care continuum for breast cancer patients between 2013 and 2023 at Vernon Jubilee Hospital. Implementing an interdisciplinary approach to care is necessary to remediate sources of delays at each step. Possible solutions include creating a fast-track pathway for symptomatic patients, performing biomarkers and pathology slide preparation locally, increasing operating room time, and tripling the number of oncologists in the region. [ABSTRACT FROM AUTHOR]