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Transforming growth factor (TGF)-β is stored in the extracellular matrix as a latent complex with its prodomain. Activation of TGF-β1 requires the binding of α v integrin to an RGD sequence in the prodomain and exertion of force on this domain, which is held in the extracellular matrix by latent TGF-β binding proteins. Crystals of dimeric porcine proTGF-β1 reveal a ring-shaped complex, a novel fold for the prodomain, and show how the prodomain shields the growth factor from recognition by receptors and alters its conformation. Complex formation between α v β 6 integrin and the prodomain is insufficient for TGF-β1 release. Force-dependent activation requires unfastening of a ‘straitjacket’ that encircles each growth-factor monomer at a position that can be locked by a disulphide bond. Sequences of all 33 TGF-β family members indicate a similar prodomain fold. The structure provides insights into the regulation of a family of growth and differentiation factors of fundamental importance in morphogenesis and homeostasis. Key growth factor structure determined Members of the transforming growth factor-β (TGF-β) superfamily of growth factors are of fundamental importance in development and tissue homeostasis. TGF-β is secreted as an inactive complex that has to be activated to enable receptor binding and activation of downstream signalling events. Cell surface adhesion receptors of the integrin family are essential for the activation of TGF-β. Shi et al . present the structure of latent TGF-β and provide mechanistic insights into latency and force-dependent activation by integrins.

H3K27me3 binding to the EED pocket of the Polycomb repressive complex 2 (PRC2) is required to activate PRC2. An allosteric small-molecule inhibitor of PRC2 was identified that binds to the EED pocket and blocks PRC2 methyltransferase activity in cells. Polycomb repressive complex 2 (PRC2) consists of three core subunits, EZH2, EED and SUZ12, and plays pivotal roles in transcriptional regulation. The catalytic subunit EZH2 methylates histone H3 lysine 27 (H3K27), and its activity is further enhanced by the binding of EED to trimethylated H3K27 (H3K27me3). Small-molecule inhibitors that compete with the cofactor S -adenosylmethionine (SAM) have been reported. Here we report the discovery of EED226, a potent and selective PRC2 inhibitor that directly binds to the H3K27me3 binding pocket of EED. EED226 induces a conformational change upon binding EED, leading to loss of PRC2 activity. EED226 shows similar activity to SAM-competitive inhibitors in blocking H3K27 methylation of PRC2 target genes and inducing regression of human lymphoma xenograft tumors. Interestingly, EED226 also effectively inhibits PRC2 containing a mutant EZH2 protein resistant to SAM-competitive inhibitors. Together, we show that EED226 inhibits PRC2 activity via an allosteric mechanism and offers an opportunity for treatment of PRC2-dependent cancers.

Receptor-mediated signal transduction modulates complex cellular behaviours such as cell growth, migration and differentiation. Although photoactivatable proteins have emerged as a powerful tool for controlling molecular interactions and signalling cascades at precise times and spaces using light, many of these light-sensitive proteins are activated by ultraviolent or visible light, which has limited tissue penetration. Here, we report a single-walled carbon nanotube (SWCNT)-assisted approach that enables near-infrared light-triggered activation of transforming growth factor β (TGF-β) signal transduction, an important signalling pathway in embryonic development and cancer progression. The protein complex of TGF-β and its latency-associated peptide is conjugated onto SWCNTs, where TGF-β is inactive. Upon near-infrared irradiation, TGF-β is released through the photothermal effect of SWCNTs and becomes active. The released TGF-β activates downstream signal transduction in live cells and modulates cellular behaviours. Furthermore, preliminary studies show that the method can be used to mediate TGF-β signalling in living mice. TGF-β signalling, which is important in regulating various cellular processes during development, can be optically manipulated using near-infrared light with the aid of single-walled carbon nanotubes.

Receptor-mediated signal transduction modulates complex cellular behaviours such as cell growth, migration and differentiation. Although photoactivatable proteins have emerged as a powerful tool for controlling molecular interactions and signalling cascades at precise times and spaces using light, many of these light-sensitive proteins are activated by ultraviolent or visible light, which has limited tissue penetration. Here, we report a single-walled carbon nanotube (SWCNT)-assisted approach that enables near-infrared light-triggered activation of transforming growth factor β (TGF-β) signal transduction, an important signalling pathway in embryonic development and cancer progression. The protein complex of TGF-β and its latency-associated peptide is conjugated onto SWCNTs, where TGF-β is inactive. Upon near-infrared irradiation, TGF-β is released through the photothermal effect of SWCNTs and becomes active. The released TGF-β activates downstream signal transduction in live cells and modulates cellular behaviours. Furthermore, preliminary studies show that the method can be used to mediate TGF-β signalling in living mice.

Transforming growth factor (TGF)-[beta] is stored in the extracellular matrix as a latent complex with its prodomain. Activation of TGF-[beta]1 requires the binding of [alpha].sub.v integrin to an RGD sequence in the prodomain and exertion of force on this domain, which is held in the extracellular matrix by latent TGF-[beta] binding proteins. Crystals of dimeric porcine proTGF-[beta]1 reveal a ring-shaped complex, a novel fold for the prodomain, and show how the prodomain shields the growth factor from recognition by receptors and alters its conformation. Complex formation between [alpha].sub.v[beta].sub.6 integrin and the prodomain is insufficient for TGF-[beta]1 release. Force-dependent activation requires unfastening of a 'straitjacket' that encircles each growth-factor monomer at a position that can be locked by a disulphide bond. Sequences of all 33 TGF-[beta] family members indicate a similar prodomain fold. The structure provides insights into the regulation of a family of growth and differentiation factors of fundamental importance in morphogenesis and homeostasis.

We report an ultra-high vacuum low-temperature scanning tunneling microscopy (STM) study of the C60 monolayer grown on Cd(0001). Individual C60 molecules adsorbed on Cd(0001) may exhibit a bright or dim contrast in STM images. When deposited at low temperatures close to 100 K, C60 thin films present a curved structure to release strain due to dominant molecule–substrate interactions. Moreover, edge dislocation appears when two different wavy structures encounter each other, which has seldomly been observed in molecular self-assembly. When growth temperature rose, we found two forms of symmetric kagome lattice superstructures, 2 × 2 and 4 × 4, at room temperature (RT) and 310 K, respectively. The results provide new insight into the growth behavior of C60 films.

The surface electric field strength directly affects the accuracy of voltage measurement in DC voltage ratio standard devices. The auxiliary device known as the voltage regulation ring effectively reduces the surface electric field strength. Therefore, optimizing the voltage regulation ring’s structural characteristics is crucial for decreasing the electric field strength and enhancing the device’s accuracy. This study initially develops a functional engineering simulation model for the device that standardizes the ratio of DC voltages, employing finite element simulation software. Adjustments are made within a feasible range to compute the electric field strength along the surface of the voltage regulation ring, constructing a dataset. Subsequently, an FCC neural network model is constructed to capture the correlation between different parameters of the voltage regulation ring and the maximum surface electric field strength, yielding a relationship model. Finally, the design of the voltage regulation ring is optimized within a finite range using the constructed FCC neural network model to obtain parameters for minimum field strength. Experimental results indicate that under optimal conditions, the minimum electric field strength is 10051.4883 V/cm, effectively reducing the surface electric field strength of the DCVRS device, and provide a reliable and useful design methodology for equipment selection.

Largish molecules on metal surfaces may act as not only the building blocks of 2D self-assemblies, but also as the template to reshape the metal surfaces. Here, we report the molecular adsorption-induced formation of the periodic nanostripe arrays of substrate atoms through long-range mass transport. When adsorbed on the close-packed Cd(0001) surface, the triphenyl bismuth (TPB) molecules form a 2D self-assembly with 4 × √13 reconstruction. Simultaneously, periodic nanostripe arrays of Cd atoms appear on the substrate terraces. High-resolution scanning tunneling microscopy (STM) images indicate that the Cd nanostrips are built from the parallel segments of Cd atomic chains with 2 × 2 reconstruction. In the mixed phase, the Cd atomic chains exhibit only high-order commensuration when situated between two molecular domains. The massive structural rearrangement of the Cd(0001) surface can be attributed to a strong molecule–substrate interaction.

The measurement of the right and left axillary arteries and aortic arch and their vessels by multi-row spiral CT angiography provides the basis for clinical catheter selection and depth for axillary artery placement. This study reported the clinical experience of 7 patients who successfully underwent ultrasound-guided percutaneous axillary artery cannulation for veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Patients who had CT angiography of the thoracic aorta at our institution between January 2020 and March 2022 were assessed for eligibility and included. The diameters of the cephalic trunk (D1), right common carotid artery (D2), right axillary artery (D3), left common carotid artery (D4), left axillary artery opening (D5), right axillary artery cannulation length (L1), and left axillary artery cannulation length (L2) were measured. The tangential angles α, β, and γ of the cephalic trunk, left common carotid artery and left subclavian and aorta was measured using an automatic angle-forming tool. The decision to use a 15F cannula for ultrasound-guided percutaneous axillary artery cannulation in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) aims to achieve optimal vascular access. This cannula size strikes a balance, providing sufficient blood flow rates for ECMO support while minimizing the risk of complications associated with larger cannulas. Precise measurements of arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries, play a crucial role in guiding catheter selection and determining the depth of axillary artery placement. These measurements allow for tailored approaches based on individual patient characteristics, enhancing the safety and efficacy of the intervention. Additionally, measuring tangential angles (α, β, and γ) provides insights into arterial alignment, optimizing the cannula trajectory for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy, minimizing complications, and ensuring the success of ultrasound-guided percutaneous axillary artery cannulation. In summary, the choice of a 15F cannula and precise measurements are essential components of the methodology, emphasizing safety, efficacy, and personalized approaches in VA-ECMO. From March to June 2022, 7 patients (6 males and 1 female) in our intensive care medicine department underwent successful ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with 15F cannula, including 3 cases with extracorporeal cardiopulmonary resuscitation (ECPR) and 4 cases with circulatory collapse. 292 patients met the study criteria, 215 males and 77 females, with a mean age of 67.2±14.2 years. The measurements showed that D1 was (13.1±2.0) mm, D2 was (8.8±2.5) mm, D3 was (6.1±1.2) mm, D4 was (8.3±3.5) mm, D5 was (6.1±1.1) mm, L1 was (114.1±17.8) mm, and L2 was (128.4±20.2) mm. The tangential angles α of the cephalic trunk left common carotid artery and left subclavian artery to the aorta were (43.8°±17.1°), β was (50.7°±14.8°), and γ was (62.4°±19.1°). Males had significantly wider D3 and D5, longer L1 and L2, and smaller gamma angles than females (P < .05). Three ECPR cases showed no recovery of the spontaneous heartbeat with femoral artery cannulation for VA-ECMO but recovered spontaneous heartbeat after axillary artery cannulation for VA-ECMO was adopted. The measurements in this study have important implications for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) procedures. They provide crucial information about arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries. This information guides clinicians in selecting catheters and determining the ideal depth for percutaneous axillary artery cannulation during ECMO interventions. Notable gender differences in arterial dimensions highlight the need for personalized approaches in ECMO procedures. Customizing catheter choices and cannulation depth based on individual patient characteristics, informed by these measurements, improves the safety and effectiveness of the intervention. The measured tangential angles (α, β, and γ) offer insights into arterial alignment, crucial for optimizing cannula trajectory and ensuring proper alignment for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy and minimizing the risk of complications during ECMO procedures. In summary, these measurements directly enhance the precision and safety of VA-ECMO procedures, underscoring the importance of personalized approaches based on individual anatomical variations and improving overall intervention success and outcomes. Ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with a 15F cannula is clinically feasible. Axillary artery cannulation for VA-ECMO contributes to the restoration of spontaneous heartbeat in ECPR patients more than femoral artery cannulation, and the possible mechanism is a better improvement of coronary blood flow. However, the study has limitations, including a modest sample size and a single-center, retrospective design, impacting its generalizability. To validate and extend these findings, further research with larger and diverse cohorts, including prospective investigations, is necessary to ensure their applicability across various clinical settings and patient demographics in VA-ECMO.

Retargeting the antigen-binding specificity of T cells to intracellular antigens that are degraded and presented on the tumor surface by engineering chimeric antigen receptor (CAR), also named TCR-like antibody CAR-T, remains limited. With the exception of the commercialized CD19 CAR-T for hematological malignancies and other CAR-T therapies aiming mostly at extracellular antigens achieving great success, the rareness and scarcity of TCR-like CAR-T therapies might be due to their current status and limitations. This review provides the probable optimized initiatives for improving TCR-like CAR-T reprogramming and discusses single-domain antibodies administered as an alternative to conventional scFvs and secreted by CAR-T cells, which might be of great value to the development of CAR-T immunotherapies for intracellular antigens.