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Background: The study was to investigate the effects of dexmedetomidine on microcirculation in patients with early septic shock despite initial resuscitation. Methods: This was a single-center prospective study. Patients with early septic shock despite initial fluid resuscitation who still required norepinephrine to maintain target arterial pressure were enrolled. Hemodynamic and gas analysis variables, sublingual microcirculatory parameters were measured at baseline, and during the infusion of dexmedetomidine for 1 h (0.7mcg/kg/h). To elucidate the possible mechanisms of the effect of dexmedetomidine on microcirculation, after interim analysis, the dose-effect relationship of dexmedetomidine on microcirculation and catecholamine level were investigated at baseline, 1h after stabilization at different doses of dexmedetomidine (0.7 and 0.3 mcg/kg/h), and 2h after dexmedetomidine cessation. Results: Forty-four patients with septic shock were enrolled after initial resuscitation. Compared with baseline, total and perfused vascular densities were statistically increased after infusion of dexmedetomidine, which was correlated with the dose of dexmedetomidine. During dexmedetomidine infusion, plasma norepinephrine, and dopamine level were significantly decreased. Changes in plasma norepinephrine level contributed to dexmedetomidine infusion were well correlated with changes in total and perfused vascular densities. Conclusions: In adult patients with resuscitated septic shock, dexmedetomidine improved microcirculation, which might be associated with plasma catecholamine level. However, double-blinded large sample studies should be performed to verify the results. Trial registration: Clinicaltrials.gov NCT02270281. Registered October 16, 2014. [ABSTRACT FROM AUTHOR]

Hydrogel sensors are widely utilized in soft robotics and tissue engineering due to their excellent mechanical properties and biocompatibility. However, in high‐water environments, traditional hydrogels can experience significant swelling, leading to decreased mechanical and electrical performance, potentially losing shape, and sensing capabilities. This study addresses these challenges by leveraging the Hofmeister effect, coupled with directional freezing and salting‐out techniques, to develop a layered, high‐strength, tough, and antiswelling PVA/MXene hydrogel. In particular, the salting‐out process enhances the self‐entanglement of PVA, resulting in an S‐PM hydrogel with a tensile strength of up to 2.87 MPa. Furthermore, the S‐PM hydrogel retains its structure and strength after 7 d of swelling, with only a 6% change in resistance. Importantly, its sensing performance is improved postswelling, a capability rarely achievable in traditional hydrogels. Moreover, the S‐PM hydrogel demonstrates faster response times and more stable resistance change rates in underwater tests, making it crucial for long‐term continuous monitoring in challenging aquatic environments, ensuring sustained operation and monitoring. [ABSTRACT FROM AUTHOR]

Nb2CTx is a candidate MXene material for lithium-ion batteries because of its advantages in ion movement, diffusion barrier, and average intercalation potentials. However, Nb2CTx nanosheets tend to self-restack when assembled into electrodes because of the strong van der Waals force between them. Electrodes with densely packed Nb2CTx nanosheets can limit the diffusion of Li-ions and impair their electrochemical performance. Here, carbon quantum dots (CQDs) are anchored on the Nb2CTx nanosheets by a hydrothermal reaction to expand the interlayer spacing and create abundant Li-ion transport channels. The CQD-Nb2CTx nanosheets have higher specific surface area (84 m2/g), more active sites, and more Li-ion diffusion paths, which can facilitate the transfer of Li-ions. The CQD-Nb2CTx electrode exhibits a high capacity of 334 mAh/g at 50 mA/g and good long-term cycling stability of 1000 cycles with 260 mAh/g at 1 A/g. [ABSTRACT FROM AUTHOR]

Flexible gas sensors, which can detect gas markers from the human body and hazardous gases from the environment, are attracting tremendous attention recently. Carbon nanotube (CNT) films are explored for flexible gas sensors due to its sensing ability at room temperature, strong adsorption for foreign molecules, mechanical robustness, and remarkable flexibility, and providing nanoscale surfaces with large surface area for various functional materials, etc. In this paper, recent advances in flexible gas sensors based on CNT films are reviewed. It discusses various strategies to design the structure of flexible CNT films and improve flexibility/stretchability performance. It generalizes different types of sensitive materials loaded for detected gases and analyzes the sensing mechanism of CNT films, with interface interactions and synergistic effects leading to an improvement in gas sensing. In addition, it discusses the preparation of CNT self‐standing films and the use of flexible substrates in transformation and assembly, in order to enable CNT films with improved flexible properties. CNT films show remarkable response and flexibility to hazard or greenhouse gases, such as ammonia, nitrogen dioxide, hydrogen, nitric oxide, carbon dioxide, and others. Summary and perspectives toward the future development of flexible gas sensors based on CNT films are proposed. [ABSTRACT FROM AUTHOR]

Compared with hydrogen evolution reaction (HER) under acidic conditions, the kinetic steps of alkaline HER are more complex, which involves the adsorption and cleavage of water molecules. Defect and interface engineering are two important means to enhance basic HER. In order to prepare catalysts with high activity and stability under both acidic and basic conditions, a defective amorphous carbon loaded with Ru nanoparticles coaxially wrapped around a carbon nanotube (CNT) sponge network is presented. The presence of amorphous carbon can promote the uniform loading of Ru nanoparticles and limit the growth of Ru nanoparticles, and also the introduction of oxygen defects can regulate the electronic structure of the metal and improve its charge transport capacity, thus enhancing the catalytic performance. The catalyst CNT/C/Ru0.37 wt%‐700 prepared under optimized conditions exhibits excellent stability and activity. At a current density of 10 mA cm−2, the overpotential of HER is as low as 38.3 and 36.2 mV under alkaline and acidic conditions, respectively, which is better than most reported Ru‐based catalysts. This study details innovative and feasible ideas for the design and preparation of loaded catalysts, which can contribute to the development of high‐performance electrochemical catalysts. [ABSTRACT FROM AUTHOR]

Fiber‐based electronic devices can be woven into textiles to provide comfort, durability, and integrated multi‐functionality, and will be widely used in the intelligent wearable field. Herein, by introducing elastic substrates and regulating the external tension during spinning to control the helical structure and optimize mechanical properties, multi‐functional Polyurethane@carbon nanotube (PU@CNT) stretchable fibers with high extensibility and flexibility is prepared for human motion detection and energy storage. A multi‐layered structure consisting of alternating MXene sheets and CNT films is also designed, to promote the relative resistance change of PU@CNT/MXene fibers to 212% (4 times than PU@CNT) when acting as strain sensors, whereas their volume specific capacitance reaches 196 F cm−3 (increases ≈50 times). Additionally, the capacitance of our stretchable fibers supercapacitors maintains at 91.4% and 86.2% when stretched statically (170% strain) or after hundreds of cycles (50% strain), respectively. It is proposed that MXene sheets can fill gaps between CNTs, resulting in more uniform distribution in fibers, which can improve strain sensitivity and long‐cycle capacitance retention. These PU@CNT/MXene fibers with unique multi‐layered hybrid structure and superior performance have potential applications in portable, wearable, and body‐integrated sensors and energy storage devices. [ABSTRACT FROM AUTHOR]

Nb2CTx is an important member of MXene family. It has attracted widespread attention because of its abundant functional groups, high hydrophilicity, high electrical conductivity as well as low ion transport barrier, showing great potential in various applications. In order to utilize the advantages of Nb2CTx MXene, the progress of preparation, properties and applications are reviewed in this work. This work focuses on different methods of Nb2CTx preparation and applications in electrochemical energy storage (supercapacitors and secondary batteries), electrocatalytic hydrogen evolution, photocatalytic hydrogen evolution, sensors, etc. Additionally, the main problems of self-stacking and prospect of Nb2CTx MXene are discussed. [ABSTRACT FROM AUTHOR]

Reduction in cardiac contractility is common in severe sepsis. However, the pathological mechanism is still not fully understood. Recently it has been found that circulating histones released after extensive immune cell death play important roles in multiple organ injury and disfunction, particularly in cardiomyocyte injury and contractility reduction. How extracellular histones cause cardiac contractility depression is still not fully clear. In this work, using cultured cardiomyocytes and a histone infusion mouse model, we demonstrate that clinically relevant histone concentrations cause significant increases in intracellular calcium concentrations with subsequent activation and enriched localization of calcium-dependent protein kinase C (PKC) α and βII into the myofilament fraction of cardiomyocytes in vitro and in vivo. Furthermore, histones induced dose-dependent phosphorylation of cardiac troponin I (cTnI) at the PKC-regulated phosphorylation residues (S43 and T144) in cultured cardiomyocytes, which was also confirmed in murine cardiomyocytes following intravenous histone injection. Specific inhibitors against PKCα and PKCβII revealed that histone-induced cTnI phosphorylation was mainly mediated by PKCα activation, but not PKCβII. Blocking PKCα also significantly abrogated histone-induced deterioration in peak shortening, duration and the velocity of shortening, and re-lengthening of cardiomyocyte contractility. These in vitro and in vivo findings collectively indicate a potential mechanism of histone-induced cardiomyocyte dysfunction driven by PKCα activation with subsequent enhanced phosphorylation of cTnI. These findings also indicate a potential mechanism of clinical cardiac dysfunction in sepsis and other critical illnesses with high levels of circulating histones, which holds the potential translational benefit to these patients by targeting circulating histones and downstream pathways. [ABSTRACT FROM AUTHOR]

In recent years, two-dimensional MXene have attracted more attentions owing to their excellent electrochemical performance, resulting their widely used in electrochemical energy storage field. However, traditional electrodes fabrication processes may result in the self-restacking of MXene nanosheets, which may lead to the low electrochemical performance of MXene based electrode materials. It is effective to design a three-dimensional aerogel to suppress the self-restacking of MXene nanosheets and develop high-performance MXene based electrode materials. Ti3 C2 Tx/rGO hybrid aerogel (A-TGA) with bidirectionally aligned structure through the bidirectional freeze casting and freeze drying method was prepared in this paper, and the mechanical performance of the hybrid aerogel was improved by the mild reduction of graphene oxide (GO). The A-TGA shows excellent mechanical properties and electrical conductivity, so it can be used as the electrode material for supercapacitors, the unique bidirectionally aligned structure provides barrier-free transport channels for electrolyte ions, which can greatly improve the electrochemical properties of A-TGA. The A-TGA shows a specific capacitance of 370 Fc ⋅ g-1 at 1 A⋅g-1 and delivers an outstanding cycling performance with a capacitance retention up to 94% over 5 000 cycles at 100 mV⋅s-1 scanning speed. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) fibers have the potential to serve as continuous nano‐fillers for structural and functional composite materials, yet there exists the interfacial problem that has hindered the development of continuous fiber reinforced composites for a long time. Here, a method to overcome this challenge by coating a thick CNT sponge around a single‐walled nanotube (SWNT) fiber is presented, and then infiltrating polymers into the sponge to construct a SWNT@polymer coaxial cable. It has been found that the residual stress‐induced deposition of amorphous carbon as an intermediate layer between the underlying SWNT fiber and the subsequently coated multi‐walled nanotube (MWNT) sponge plays a key role in interfacial properties, and together with well‐dispersed CNT in the polymer matrix, a superior interfacial shear strength (>12 MPa), enhanced tensile strength and toughness is achieved. These coaxial cables demonstrate high mechanical damping ability and can serve as stretchable conductors maintaining high electrical conductivity during large‐strain cyclic deformation. These results indicate a promising route toward developing continuous CNT fiber‐based composites with wide applications as structural and multi‐functional composite materials. [ABSTRACT FROM AUTHOR]

Hydrophobic membranes have been considered as one of the most effective candidates in oil/water separation for their easy operation and high efficiency. Here, we prepared a hydrophobic carbon nanotube (CNT)/carbon nanofiber (CNF) hybrid membrane by in situ grafting CNTs on a CNF membrane. The CNT grafting significantly increased the porosity and hydrophobicity of the CNF membrane. As a result, the CNT/CNF hybrid membrane showed a high efficiency (80%–98%) in the separation of a range of oil/water mixtures. Moreover, the CNT/CNF hybrid membrane is recyclable, and the separation efficiency maintained after 10 cycles. This high separation efficiency and good recyclability provide feasibilities for practical applications of the CNT/CNF hybrid membrane in the purification of oil contaminated water. [ABSTRACT FROM AUTHOR]

Pulmonary microvascular endothelial cells (PMECs) and the extracellular vesicles (EVs) derived from PMECs participate in maintaining pulmonary homeostasis and mediating the inflammatory response. However, obtaining a high-purity population of PMECs and their EVs from mouse is still notoriously difficult. Herein we provide a method to isolate primary mouse PMECs (pMPMECs) and to transduce SV40 lentivirus into pMPMECs to establish an immortalized cell line (iMPMECs), which provides sufficient quantities of EVs for further studies. pMPMECs and iMPMECs can be identified using morphologic criteria, a phenotypic expression profile (e. g., CD31, CD144, G. simplicifolia lectin binding), and functional properties (e. g., Dil-acetylated low-density protein uptake, Matrigel angiogenesis). Furthermore, pMPMEC–EVs and iMPMEC–EVs can be identified and compared. The characteristics of pMPMEC–EVs and iMPMEC–EVs are ascertained by transmission electron microscopy, nanoparticle tracking analysis, and specific protein markers. iMPMECs produce far more EVs than pMPMECs, while their particle size distribution is similar. Our detailed protocol to isolate and immortalize MPMECs will provide researchers with an in vitro model to investigate the specific roles of EVs in pulmonary physiology and diseases. [ABSTRACT FROM AUTHOR]

In recent years, the catalyst efficiency of hydrogen evolution reaction (HER) has been extensively studied. However, the stability of catalysts at high current densities is still a challenge. Herein, layered Ni−Co−P was electrodeposited on carbon fiber paper (CFP) via cyclic voltammetry (CV). This low‐cost electrode exhibits high efficiency and excellent durability for HER in 1 M KOH. To achieve current densities of 10, 100, 500, and 1000 mA cm−2, Ni−Co−P/CFP required overpotentials of 49, 95, 170, and 295 mV, respectively. The layered structure allows the catalyst to fall off layer by layer. After the outer layer of catalyst falls off, the inner layer of catalyst will be exposed to continue working. After 300 h of HER at 1000 mA cm−2, Ni−Co−P/CFP still has a regular morphology and high efficiency. Our work shows that layered Ni−Co−P/CFP has excellent prospects for practical applications. [ABSTRACT FROM AUTHOR]

There is no detailed study on how tidal volume (VT) affects patients during one-lung ventilation (OLV). The present study conducted a meta-analysis to assess the effect of VT on physiology and clinical outcomes in OLV patients. Databases until February 2023 were retrieved from PubMed, Cochrane Library and Web of Science. Randomized controlled trials comparing the application of low and high VT ventilation in adults with OLV were performed. Demographic variables, VT, physiology, and clinical outcomes were retrieved. The random-effects model calculated the summary of odds ratios with 95% confidence intervals (CI) and mean difference with standard deviation. A total of 12 studies involving a total of 876 participants met the inclusion criteria. Low VT ventilation was associated with decreased risk of acute lung injury [relative risk 0.50, 95% CI (0.28, 0.88), P=0.02]. Low VT ventilation decreased the driving pressure (ΔP) and peak pressure (Ppeak) and improved arterial oxygen pressure (PaO2)/fraction of inspired oxygen (FiO2). Furthermore, the present study suggested that a significant difference in blood IL-6 was observed between low and high VT ventilation [mean difference, -35.51 pg/ml, 95% CI (-66.47, -4.54 pg/ml), P=0.02]. A decrease in the length of stay at the hospital occurred in the low VT group when set to 4-5 ml/kg. In the OLV patients, low VT ventilation decreased the risk of acute lung injury, blood IL-6, ΔP and Ppeak, and improved PaO2/FiO2. Furthermore, when low VT was set to 4-5 ml/kg, the length of stay at the hospital decreased. [ABSTRACT FROM AUTHOR]