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Background: Healthcare systems contribute 5%–10% of the global carbon footprint. Given the detrimental impact of climate change on population health, health systems must seek to address this environmental responsibility. This is especially relevant in the modern era of minimally invasive procedures (MIP) where single‐use instruments are increasingly popular. We compared the environmental footprint of single‐use versus multi‐use instruments in MIP. Methods: We conducted a systematic review across five databases to identify relevant original studies, following the PRISMA guidelines. We extracted environmental impact data and performed a quality assessment of included studies. Results: We included 13 studies published between 2005 and 2024. Eight employed Life Cycle Analysis (LCAs), which is the gold standard methodology for studies evaluating environmental impact. The instruments studied included laparoscopy systems, endoscopes, cystoscopes, bronchoscopes, duodenoscopes, and ureteroscopes. Six studies, including three high quality LCAs and one fair quality LCA, showed that single‐use instruments have a significantly higher environmental footprint than their multi‐use counterparts. Six studies suggested a lower environmental footprint for single‐use instruments, and one study presented comparable results. However, these studies were of poor/fair quality. Conclusion: Although our systematic review yielded mixed results, all high quality LCAs suggested multi‐use instruments may be more environmentally friendly than their single‐use counterparts. Our findings are limited by inter‐study heterogeneity and methodological quality. There is an urgent need for additional research employing gold standard methodologies to explore the interplay between environmental impact and operational factors such as workflow efficiency and cost‐benefit ratio to allow health systems to make more informed decisions. [ABSTRACT FROM AUTHOR]

Background/Objectives: Collagen–agarose hydrogel blends currently used in tracheal graft bioengineering contain relatively high concentrations of collagen to withstand mechanical stresses associated with native trachea function (e.g., breathing). Unfortunately, the high collagen content restricts effective cell infiltration into the hydrogel. In this study, we created an improved hydrogel blend with lower concentrations of collagen (<5 mg/mL) and characterized its capacity for fibroblast invasion and angiogenesis. Methods: Four collagen–agarose hydrogel blends were created: 1 mg/mL type 1 collagen (T1C) and 0.25% agarose, 1 mg/mL T1C and 0.125% agarose, 2 mg/mL T1C and 0.25% agarose, and 2 mg/mL T1C and 0.125% agarose. The hydrogel surface was seeded with fibroblasts, while both endothelial cells and fibroblasts (3:1 ratio) were mixed within the hydrogel matrix. We assessed early angiogenesis by observing fibroblast migration and endothelial cell morphology (elongation and branching) at 7 days. In addition, we performed immunostaining for alpha-smooth muscle actin (aSMA) and explored the gene expression of various angiogenic markers (including vascular endothelial growth factor; VEGF). Results: Gels with lower agarose concentrations (0.125%) with 1 or 2 mg/mL T1C were more effective in allowing early attachment and migration of surface-applied fibroblasts compared to gels with higher (0.25%) agarose concentrations. The low-agarose gels also allowed cells to quickly adopt a spread morphology and self-assemble into elongated structures indicative of early angiogenesis, while demonstrating positive immunostaining for aSMA and increased gene expression of VEGF by day 7. Conclusions: Hydrogel blends with collagen and low agarose concentrations may be effective in allowing early cellular infiltration and angiogenesis, making such gels a suitable cell substrate for use in the development of composite bioengineered tracheal grafts. The collagen–agarose hydrogel blend is meant to be cast around a three-dimensional (3D) printed polycaprolactone support structure and wrapped in porcine small intestine submucosa ECM to create an off-the-shelf bioengineered tracheal implant. [ABSTRACT FROM AUTHOR]

Bi-component, polyacrylonitrile (PAN)/carbon nanotube (CNT) fibers were processed, at different core-sheath area ratios, by gel spinning. A percolated CNT network at 10 wt% CNT in the sheath enhanced electrical conductivity as compared to the neat PAN fiber, while PAN polymer in the core contributed to the good mechanical properties. Fibers with relatively thin sheath allowed overall CNT loading as low as 3.7 wt% to be made with good electrical conductivity, and PAN stabilization by Joule heating was demonstrated. Such fibers with combined good mechanical properties and electrical conductivity can also potentially be used for electrical heating of fabrics, for making smart textiles, and for electromagnetic interference shielding. KEYWORDS carbon nanotubes, electrical properties, joule heating, multifunctional composites, nanocomposites, 1 | INTRODUCTION Carbon nanotubes (CNTs) are being used as reinforcement material due to their good mechanical, electrical, and thermal properties. [1-3] Most polymer/CNT fibers reported to date, generally possess [...]

Introduction: While most patients with iatrogenic tracheal stenosis (ITS) respond to endoscopic ablative procedures, approximately 15% experience a recalcitrant, recurring disease course that is resistant to conventional management. We aimed to explore genetic profiles of patients with recalcitrant ITS to understand underlying pathophysiology and identify novel therapeutic options. Methods: We collected 11 samples of granulation tissue from patients with ITS and performed RNA sequencing. We identified the top 10 most highly up- and down-regulated genes and cellular processes that these genes corresponded to. For the most highly dysregulated genes, we identified potential therapeutic options that favorably regulate their expression. Results: The dysregulations in gene expression corresponded to hyperkeratinization (upregulation of genes involved in keratin production and keratinocyte differentiation) and cellular proliferation (downregulation of cell cycle regulating and pro-apoptotic genes). Genes involved in retinoic acid (RA) metabolism and signaling were dysregulated in a pattern suggesting local cellular RA deficiency. Consequently, RA also emerged as the most promising potential therapeutic option for ITS, as it favorably regulated seven of the ten most highly dysregulated genes. Conclusion: This is the first study to characterize the role of hyperkeratinization and dysregulations in RA metabolism and signaling in the disease pathophysiology. Given the ability of RA to favorably regulate key genes involved in ITS, future studies must explore its efficacy as a potential therapeutic option for patients with recalcitrant ITS. [ABSTRACT FROM AUTHOR]

Nanoparticle‐based nucleic acid conjugates (NP‐NACs) hold great promise for theragnostic applications. However, several limitations have hindered the realization of their full potential in the clinical treatment of cancer and other diseases. In diagnoses, NP‐NACs suffer from low signal‐to‐noise ratios, while the efficiency of NP‐NACs‐mediated cancer therapies has been limited by the adaptation of alternative prosurvival pathways in cancer cells. The recent emergence of personalized and precision medicine has outlined the importance of having both accurate diagnosis and efficient therapeutics in a single platform. As such, the controlled assembly of hybrid graphene oxide/gold nanoparticle (Au@GO NP)‐based cancer‐specific NACs (Au@GO NP‐NACs) for multimodal imaging and combined therapeutics is reported. The developed Au@GO NP‐NACs show excellent surface‐enhanced Raman scattering (SERS)‐mediated live‐cell cancer detection and multimodal synergistic cancer therapy through the use of photothermal, genetic, and chemotherapeutic strategies. Synergistic and selective killing of cancer cells are then demonstrated using in vitro microfluidic models. Moreover, with the distinctive advantages of the Au@GO NP‐NACs for cancer theragnostics, precision cancer treatment through the detection of cancer cells in vivo using SERS followed by efficient ablation of tumors is shown. Therefore, the Au@GO NP‐NACs can pave a new road for advanced disease theragnostics. [ABSTRACT FROM AUTHOR]

Bone morphogenetic proteins (BMPs) belong to the TGF-β superfamily and play an important role in development and in many cellular processes. We have found that BMP-2, BMP-6, and BMP-9 induce the most potent osteogenic differentiation of mesenchymal stem cells. Expression profiling analysis has revealed that the Inhibitors of DNA binding/differentiation (Id)-1, Id-2, and Id-3 are among the most significantly up-regulated genes upon BMP-2, BMP-6, or BMP-9 stimulation. Here, we sought to determine the functional role of these Id proteins in BMP-induced osteoblast differentiation. We demonstrated that the expression of Id-1, Id-2, and Id-3 genes was significantly induced at the early stage of BMP-9 stimulation and returned to basal levels at 3 days after stimulation. RNA interference-mediated knockdown of Id expression significantly diminished the BMP-9-induced osteogenic differentiation of mesenchymal progenitor cells. Surprisingly, a constitutive overexpression of these Id genes also inhibited osteoblast differentiation initiated by BMP-9. Furthermore, we demonstrated that BMP-9-regulated Id expression is Smad4-dependent. Overexpression of the three Id genes was shown to promote cell proliferation that was coupled with an inhibition of osteogenic differentiation. Thus, our findings suggest that the Id helix-loop-helix proteins may play an important role in promoting the proliferation of early osteoblast progenitor cells and that Id expression must be down-regulated during the terminal differentiation of committed osteoblasts, suggesting that a balanced regulation of Id expression may be critical to BMP-induced osteoblast lineage-specific differentiation of mesenchymal stem cells. [ABSTRACT FROM AUTHOR]