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Actin assembly supplies the structural framework for cell morphology and migration. Beyond structure, this actin framework can also be engaged to drive biochemical signaling programs. Here, we describe how the hyperactivation of Rac1 via the P29S mutation (Rac1P29S) in melanoma hijacks branched actin network assembly to coordinate proliferative cues that facilitate metastasis and drug resistance. Upon growth challenge, Rac1P29S-harboring melanoma cells massively upregulate lamellipodia formation by dendritic actin polymerization. These extended lamellipodia form a signaling microdomain that sequesters and phospho-inactivates the tumor suppressor NF2/Merlin, driving Rac1P29S cell proliferation in growth suppressive conditions. These biochemically active lamellipodia require cell-substrate attachment but not focal adhesion assembly and drive proliferation independently of the ERK/MAPK pathway. These data suggest a critical link between cell morphology and cell signaling and reconcile the dichotomy of Rac1's regulation of both proliferation and actin assembly by revealing a mutual signaling axis wherein actin assembly drives proliferation in melanoma.

Background: The opioid epidemic is a health crisis in the United States. Physicians contribute to this problem by overprescribing opioids. Ambulatory hand surgery (AHS) is common in the United States and associated with overprescribing of opioids. Education and guidance regarding the effectiveness of nonopioid compared with opioid interventions for pain management following ambulatory hand procedures are lacking. We assessed the current literature to suggest evidence-based protocols for postoperative analgesia. Methods: A systematic review was performed using PubMed, Web of Science, and Cochrane Library. Studies comparing nonopioid with opioid treatments for pain management following AHS were identified. Studies investigating opioid-sparing strategies after AHS were also identified. Evidence was examined to determine efficacy of nonopioid interventions and to provide recommendations for optimal nonopioid protocols and opioid-sparing strategies. Results: A total of 510 studies were identified in the search with 18 meeting inclusion criteria. High-level evidence demonstrated efficacy of nonopioid interventions for pain management following AHS (levels I and II evidence). Results provided evidence-based guidelines for recommendations of nonopioid treatment protocols and opioid-sparing strategies (levels I and II evidence). Conclusions: Our review demonstrated nonopioid interventions are adequate in multiple aspects of pain management compared with opioid treatments. Recommendations were established for two nonopioid treatment protocols, and for an opioid-sparing intervention (levels I and II evidence). The evidence provided in this review should be strongly considered for pain management guidance following AHS and provides a means to decrease opioid overprescribing in the United States. [ABSTRACT FROM AUTHOR]

Large defects of the lip pose a reconstructive challenge due to the prominent facial location, significant impact on self-image and quality of life, and effects on functional needs such as oral competence, sensation, articulation, and maintenance of normal range of incisal opening. Current lip reconstruction practice follows guidelines based on defect depth and size. Optimal outcomes are achieved with use of local tissues which achieve better color, texture match, and ability to maintain sensation and orbicularis function. However, this is not usually possible in large defects. Cleft repair principles revolve around many of the similar goals of traumatic and oncologic lip reconstruction—to improve function and aesthetics. The authors present a case of a young male who sustained a traumatic lower lip avulsion defect involving greater than 75% of his lower lip. This was fully reconstructed using principles borrowed from cleft lip component repair, thus eliminating the need for a free flap without or without a tendon graft. This approach optimized aesthetic and functional outcomes, while avoiding several of the drawbacks of the classic oral flap reconstruction, especially in a young patient without static rhytids to camouflage reconstructive scars. In the presented technique, the senior author (OAA) successfully designed a modification of the classic Karapandzic repair technique utilizing principles from cleft lip reconstruction to address skin, muscle, and mucosa in separate components. This new modification of a classic technique presented by the authors utilizes principles from cleft lip reconstruction for improved functional and aesthetic outcomes in a single-stage reconstruction. This cross-pollination of principles resulted in the successful modification of traditional techniques leading to improved aesthetics, sensate reconstruction, complete oral competence, good maximal incisal opening and color match, and decreased scar burden. [ABSTRACT FROM AUTHOR]

Laboratory practicals are used throughout science and engineering education as it allows students to undertake active learning and develop technical skills. It is therefore important that students arrive to these sessions as prepared as possible to maximise their learning potential. This paper analyses how student preparation affects how prepared they feel to undertake a laboratory practical. It also examines how pre-laboratory video material can affect this preparedness and student marks. Data on student preparedness and preparation is collected via surveys over three years of the same module. Data on video views and retention are collected from YouTube. Findings indicate that students' preparedness increases with time spent preparing, up to a plateau level where further preparation has little affect. Students who watch the pre-laboratory videos increase their preparedness and also increase their assessment mark. Guidelines for creating successful pre-activity videos have been developed and shown to be effective.

Abstract Background Every biological experiment requires a choice of throughput balanced against physiological relevance. Most primary drug screens neglect critical parameters such as microenvironmental conditions, cell-cell heterogeneity, and specific readouts of cell fate for the sake of throughput. Methods Here we describe a methodology to quantify proliferation and viability of single cells in 3D culture conditions by leveraging automated microscopy and image analysis to facilitate reliable and high-throughput measurements. We detail experimental conditions that can be adjusted to increase either throughput or robustness of the assay, and we provide a stand alone image analysis program for users who wish to implement this 3D drug screening assay in high throughput. Results We demonstrate this approach by evaluating a combination of RAF and MEK inhibitors on melanoma cells, showing that cells cultured in 3D collagen-based matrices are more sensitive than cells grown in 2D culture, and that cell proliferation is much more sensitive than cell viability. We also find that cells grown in 3D cultured spheroids exhibit equivalent sensitivity to single cells grown in 3D collagen, suggesting that for the case of melanoma, a 3D single cell model may be equally effective for drug identification as 3D spheroids models. The single cell resolution of this approach enables stratification of heterogeneous populations of cells into differentially responsive subtypes upon drug treatment, which we demonstrate by determining the effect of RAK/MEK inhibition on melanoma cells co-cultured with fibroblasts. Furthermore, we show that spheroids grown from single cells exhibit dramatic heterogeneity to drug response, suggesting that heritable drug resistance can arise stochastically in single cells but be retained by subsequent generations. Conclusion In summary, image-based analysis renders cell fate detection robust, sensitive, and high-throughput, enabling cell fate evaluation of single cells in more complex microenvironmental conditions.

This study delves into the exploration of B′ site arranged Cs 2 NaB′Cl 5 perovskites (B′ = Ni, Mn, Fe) as prospective alternatives to lead-based perovskites, given the environmental concerns associated with lead toxicity and material instability. Structural analysis using X-ray diffraction revealed a stable tetragonal crystal structure with the P4/mmm space group. Electronic properties, assessed via density functional theory (DFT) calculations, identified these materials as p-type semiconductors with tunable band gaps, and this finding supported by optical experimental data. Thermogravimetric analysis (TGA) demonstrated decomposition temperatures up to 750 °C, with Cs 2 NaMnCl 5 exhibiting superior thermal stability. Field emission scanning electron microscopy (FESEM) unveiled distinct morphologies influenced by the transition metal in the B′ site, while elemental analysis confirmed material purity. The optical analysis revealed strong light absorption in the visible spectrum, highlighting the potential of these materials for sustainable energy conversion applications. Overall, this research contributes valuable insights into the environmental-friendly potential of B′ site arranged Cs 2 NaB′Cl 5 perovskites in photoelectrochemical and solar cell application. [Display omitted] • Theoretical and experimental studies were carried out for Cs 2 Na B′ Cl 5. • Band structure was stimulated using DFT. • Cs 2 Na B′ Cl 5 (B′ = Ni, Mn, Fe) was synthesized using a simple solution method. • Band gaps of the Cs 2 Na B′ Cl 5 (B′ = Ni, Mn, Fe) were found to be 1.6–2 eV. • Dielectric constants, extinction coefficient, and refractive index are conferred. [ABSTRACT FROM AUTHOR]