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Long-term epidermal recording of bioelectricity is of paramount importance for personal health monitoring. It requires stretchable and dry film electrodes that can be seamlessly integrated with skin. The simultaneous achievement of high conductivity and skin-like ductility of conducting materials is a prerequisite for reliable signal transduction at the dynamic interface, which is also the bottleneck of epidermal electrophysiology. Here, carbon nanotubes (CNTs) are introduced as "conjugation linkers" into a topologically plasticized conducting polymer (PEDOT:PSS). A thin-film electrode with high conductivity (≈3250 S cm-1) and high stretchability (crack-onset strain>100%) is obtained. In particular, the conjugation linker enables the high volumetric capacitance and the low film resistance, both of which synergically reduce the interfacial impedance. The capabilities of this electrode is further demonstrated in the precise recording of various electrophysiological signals.
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Electrohydrodynamic (EHD) jet printing is a widely employed technology to create high-resolution patterns and thus has enormous potential for circuit production. However, achieving both high conductivity and high resolution in printed polymer electrodes is a challenging task. Here, by modulating the aggregation state of the conducting polymer in the solution and solid phases, a stable and continuous jetting of PEDOT:PSS is realized, and high-conductivity electrode arrays are prepared. The line width reaches less than 5 µm with a record-high conductivity of 1250 S/cm. Organic field-effect transistors (OFETs) are further developed by combining printed source/drain electrodes with ultrathin organic semiconductor crystals. These OFETs show great light sensitivity, with a specific detectivity (D*) value of 2.86 × 1014 Jones. In addition, a proof-of-concept fully transparent phototransistor is demonstrated, which opens up new pathways to multidimensional optical imaging.
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Background: With the increasing focus on addressing the challenges of aging, researchers have begun to recognize the potential impact of empowering older individuals in addressing retirement issues. However, within different cultural contexts, there still needs to be a more precise analysis regarding the definition of empowering older individuals. Objective: To define and analyze the concept of empowering older individuals within the cultural context of China. Method: Using Rodgers' concept analysis approach, a search was conducted in five databases (PubMed, Web of Science, China National Knowledge Infrastructure, Wan fang Data, and VIP Chinese Journal Platform) for studies on empowering older individuals from the time the databases were established until February 2023. The main disciplines involved in the search included nursing, medicine, and public health. Results: Out of the 7,028 studies, 50 articles met the inclusion criteria. The identified attributes are as follows: support system, belief change, and behavioral autonomy. The antecedents were grouped into four categories: physical obstacles, psychological concerns, personal needs and external challenges. The consequences were determined to be improved quality of life, reduced burden of old-age care, gain respect, and self-actualization. Conclusion: Empowering older individuals is a dynamic and evolving concept that involves aligning personal aspirations with appropriate external resources and expressing a certain degree of belief and behavioral change. This study deepens our understanding of empowering older individuals through comprehensive concept analysis, and the identified attributes, antecedents, and consequences of empowering older individuals can be utilized in practice, education, and research.
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Background: Many diseases are accompanied by portal vein thrombosis (PVT), and its nature is closely related to its prognosis and treatment. It is important to evaluate magnetic resonance imaging (MRI) parameters, including susceptibility-weighted imaging (SWI) and qualitative diffusion-weighted imaging (DWI), in the differentiation between benign and malignant PVT. Methods: In this retrospective study, we collected clinical imaging data from 140 patients with PVTs characterized as benign or malignant based on enhanced MRI between January 2011 and April 2016 and retrospectively analyzed PVTs using SWI and DWI. There were 37 benign and 103 malignant PVTs. Image review was performed by 2 radiologists blinded to clinical information. The signal intensity (SI) of PVTs was recorded on SWI. The apparent diffusion coefficient (ADC) and the ratio of signal intensity (SIR) on SWI (SIRSWI) and ADC (SIRADC) between the PVTs and the spinal cord were calculated. Finally, we generated receiver operating characteristic (ROC) curves to evaluate the efficacy of SIRSWI and SIRADC for distinguishing benign and malignant PVTs. Results: On SWI and DWI, 100.0% (36/36) and 80.5% (29/36) of benign PVTs were hypointense, respectively. For malignant PVTs on SWI and DWI, 99.0% (103/104) and 89.4% (93/104) were hyperintense, respectively. The SIRSWI values of benign and malignant PVTs were 0.58±0.13 and 0.88±0.06, respectively, representing a significant difference (P<0.001). The SIRADC values of benign and malignant PVTs were 0.72±0.32 and 0.62±0.17, respectively, representing a significant difference (P=0.034). The area under the ROC curve (AUROC) for SIRSWI [0.990; 95% confidence interval (CI): 0.971-1.000] was significantly higher than that for SIRADC (0.619; 95% CI: 0.500-0.737; P<0.001). The SIRSWI had a sensitivity of 100.0% and a specificity of 97.3% with a cutoff value of 0.749, while the SIRADC had a sensitivity of 45.9% and specificity of 83.3% with a cutoff value of 0.791. Conclusions: The diagnostic performance of SWI is superior to that of DWI in the differentiation of benign and malignant PVTs.
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BACKGROUND: Spontaneous jugular venous ectasia (SJVE) is characterized by dilation of the internal jugular vein (IJV) and external jugular vein. It is generally considered a benign anomaly. There is no accepted categorization for this disorder. METHODS: We conducted a case series study and a systematic review of available articles on SJVE to understand the main characteristics, clinicopathologic classifications, and therapeutic approaches. RESULTS: From January 2001 to December 2021, 14 patients in our hospital were analyzed. A total of 110 original articles (295 cases/311 lesions) were included in the systematic review. We proposed a classification and categorized SJVE into 4 main types (type I-IV) plus one (type V) in which the specific ectasia was located around the jugular bulb at the IJV. CONCLUSIONS: Conservative treatment is preferred for patients with type I (without thrombus) SJVE and asymptomatic patients who can be treated without anticoagulants. The therapeutic efficiency of surgery was high, and the best surgical modalities were chosen according to the type of SJVE.
Subject(s)
Thrombosis , Vascular Diseases , Humans , Dilatation, Pathologic , Treatment Outcome , Subclavian Vein , Jugular Veins/surgeryABSTRACT
Objective: The aim of this study is to discern the challenges and coping experiences encountered by nursing staff in long-term care facilities in China. This will be achieved through the identification, evaluation, and qualitative synthesis of comprehensive data. Design: This is a qualitative meta-analysis. Methods: The research systematically examined relevant literature sourced from six databases, concluding the search in August 2023. The inclusion criteria encompassed qualitative and mixed-methods studies in both Chinese and English, focusing on challenges faced by nursing staff in long-term care facilities and their corresponding coping strategies. The application of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework facilitated the qualitative meta-integration process. Three independent researchers meticulously screened and assessed the quality of the chosen studies. The synthesis process sought to amalgamate and structure analogous findings into novel categories through multiple readings of the original literature. These categories were subsequently distilled into comprehensive themes. Results: Analyzed 15 articles revealed 14 sub-themes and 4 overarching analytical themes. These encompassed Sources of Challenges such as multitasking, clinical emergencies, workplace conflict, demand exceeding resources, and occupational discrimination. Psychological impacts included suppressed emotion, compassion fatigue, and self-doubt. Practical consequences involved damaged health, imbalanced life, and occupational disappointment. Coping strategies identified were self-adjusting, feeling validation and belonging, and finding support. Conclusion: Our research identified the challenges faced by nursing staff in Chinese long-term care facilities and their coping experiences. We found that most challenges could be mitigated through appropriate adjustments in managerial strategies, such as reasonable human resources planning, and providing resource support, including material, emotional, and informational support. Similarly, institutions should have offered necessary emotional and psychological support to nursing staff to overcome the negative impacts of challenges and encourage them to adopt positive coping strategies.
Subject(s)
Long-Term Care , Nursing Staff , Humans , China , Asian People , Coping SkillsABSTRACT
BACKGROUND: Thrombotic popliteal artery aneurysm (PAA) with acute lower limb ischemia (ALI) is a serious disease leading to amputation. The choice of emergency procedures is not clearly defined, and the difference in therapeutic efficiency between open surgery and endovascular intervention is still unclear. METHOD: We conducted a comprehensive search through PubMed, Wiley Online Library and ScienceDirect. According to the predefined inclusion and exclusion criteria, eligible articles were screened out, and all relevant data were extracted for further analysis. Our study was designed and developed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guideline. We critically assessed all included articles by Joanna Briggs Institute (JBI) Critical Appraisal Checklists and the Methodological Index for Non-Randomized Studies (MINORS). RESULT: A total of 29 articles (1338 patients/1387 limbs) were included in the study. After a 1-year follow-up, the primary patency rate of the open surgery group was significantly lower than that of the endovascular intervention group (72.65 vs. 81.46%, P = 0.004), but without significant difference in the secondary patency rate (86.19 vs. 86.86%, P = 0.825). The limb salvage rate of the open surgery group was also significantly lower (83.07 vs. 98.25%, P < 0.001). After the 2-year follow-up, the primary patency rate of the open surgery group was still significantly lower (48.57 vs. 59.90%, P = 0.021). CONCLUSION: The outcome of endovascular intervention was better than that of open surgery especially in the 1-year limb salvage rate and primary patency rate at the 1-year and 2-year follow-ups.
Subject(s)
Aneurysm , Endovascular Procedures , Thrombosis , Humans , Popliteal Artery/surgery , Ischemia/etiology , Ischemia/surgery , Aneurysm/complications , Aneurysm/surgery , Limb Salvage , Thrombosis/complications , Thrombosis/surgeryABSTRACT
Self-defensive antimicrobial surfaces are of interest because they can inhibit bacterial colonization while minimizing unnecessary antimicrobial release in the absence of a bacterial challenge. One self-defensive approach uses self-assembly to first deposit a submonolayer coating of polyelectrolyte microgels and subsequently load those microgels by complexation with small-molecule antimicrobials. The microgel/antimicrobial complexation strength is a key parameter that controls the ability of the antimicrobial both to remain sequestered within the microgels when exposed to medium and to release in response to a bacterial challenge. Here we study the relative complexation strengths of two FDA-approved cationic antibioticsâcolistin (polymyxin E) and polymyxin Bâwith microgels of poly(styrene sulfonate) (PSS). These polymyxins are similar cyclic polypeptides with +5 charge at pH 7.4. However, polymyxin B substitutes an aromatic ring for a dimethyl moiety in colistin, and this aromaticity can influence complexation via π and hydrophobic interactions. Coarse-grained molecular dynamics shows that the free-energy change associated with polymyxin B/PSS complexation is more negative than that of colistin/PSS complexation. Experimentally, in situ optical microscopy of microgel deswelling shows that both antibiotics load quickly from low-ionic-strength phosphate buffer. The enhanced polymyxin B/PSS complexation strength is then manifested by subsequent exposure to flowing antibiotic-free buffer with varying NaCl concentration. Microgels loaded with polymyxin B remain stably deswollen to higher salt concentrations than do colistin/PSS microgels. Importantly, exposing loaded microgels to E. coli in nutrient-free-flowing phosphate buffer shows that bacteria are killed by physical contact with the loaded microgels consistent with the contact-transfer mechanism of self-defensiveness. In vitro culture experiments show that these same surfaces, nevertheless, support the adhesion, spreading and proliferation of human fetal osteoblasts. These findings suggest a pathway to create a self-defensive antimicrobial surface effective under physiological conditions based on the nonmetabolic bacteria-triggered release of FDA-approved antibiotics.
Subject(s)
Anti-Infective Agents , Microgels , Humans , Polymyxins , Colistin/pharmacology , Escherichia coli , Styrene , Polymyxin B/pharmacology , Anti-Infective Agents/pharmacology , Anti-Bacterial Agents/pharmacology , PhosphatesABSTRACT
2D materials are increasingly becoming key components in modern electronics because of their prominent electronic and optoelectronic properties. The central and premise to the entire discipline of 2D materials lie in the high-quality and scaled preparations. The chemical vapor deposition (CVD) method offers compelling benefits in terms of scalability and controllability in shaping large-area and high-quality 2D materials. The past few years have witnessed development of numerous CVD growth strategies, with the use of additives attracting substantial attention in the production of scaled 2D crystals. This review provides an overview of different additives used in CVD growth of 2D materials, as well as a methodical demonstration of their vital roles. In addition, the intrinsic mechanisms of the production of scaled 2D crystals with additives are also discussed. Lastly, reliable guidance on the future design of optimal CVD synthesis routes is provided by analyzing the accessibility, pricing, by-products, controllability, universality, and commercialization of various additives.
Subject(s)
Cardiovascular Diseases , Electronics , Gases , HumansABSTRACT
Background: This study aimed to investigate whether visceral adipose tissue index (VATI) is a significant risk factor for the early recurrence (ER) of HBV-related hepatocellular carcinoma (HCC) (≤5â cm) after hepatectomy. Methods: The recruited cohort patients who were positive for hepatitis B virus, presented with surgically confirmed HCC (≤5â cm) from Army Medical University (internal training cohort: n = 192) and Chongqing Medical University (external validation group: n = 46). We measured VATI, subcutaneous adipose tissue index (SATI) via computed tomography (CT). ER was defined as recurrence within 2 years after hepatectomy. The impact of parameters on outcome after hepatectomy for HCC was analyzed. Results: Univariate analysis showed that alpha-fetoprotein levels (p = 0.044), body mass index (BMI) (p < 0.001), SATI (p < 0.001), and VATI (p < 0.001) were significantly different between ER and non-ER groups in internal training cohort. Multivariate analysis identified VATI as an independent risk factor for ER (odds ratio = 1.07, 95% confidence interval: 1.047-1.094, p < 0.001), with a AUC of 0.802, based on the cut-off value of VATI, which was divided into high risk (≥37.45â cm2/m2) and low risk (<37.45â cm2/m2) groups. The prognosis of low risk group was significantly higher than that of high risk group (p < 0.001). The AUC value of VATI in external validation group was 0.854. Conclusion: VATI was an independent risk factor for the ER, and higher VATI was closely related to poor outcomes after hepatectomy for HBV-related HCC (≤5â cm).
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Despite the fact that scanning electron microscopes (SEM) coupled with energy-dispersive X-ray microanalysis (EDS) has been commercially available for more than a half-century, SEM/EDS continues to develop and open new opportunities to study the morphology of advanced materials. This is particularly true in applications to hydrated soft matter. Developments in field-emission electron sources that enable low-voltage imaging of uncoated polymers, silicon-drift detectors that enable high-efficiency collection of X-rays characteristic of light elements, and cryogenic methods to effectively cryo-fix hydrated samples have opened new opportunities to apply techniques relatively well established in hard-materials applications to challenging new problems involving synthetic polymers. We have applied cryo-SEM imaging and spatially resolved EDS to collect new information characterizing polyelectrolyte microgels. These are charged gel particles with dimensions in the range of 0.1-100 µm. Perhaps most notable is the fact that the high hydration levels-the samples are mostly water-allow robust calibration curves to be generated using frozen-hydrated buffers with known salt and/or hydrocarbon compositions. Such calibration curves enable quantitative composition measurements in the low-concentration extremes associated with high-swelling hydrogels. We use an experimentally derived carbon calibration curve to determine the microgel swell ratio, Q. The swell ratio, arguably, is the single most important gel characteristic because it is directly related to the mesh size of the networked polymer, which in turn determines many of the gel's mechanical and transport properties. While Q can be experimentally measured in macroscopic gels based on weight measurements in the dry and hydrated states, it is very difficult to measure in a microgel, and the fact that EDS in a cryo-SEM can determine Q from a single X-ray spectrum is significant. Furthermore, because of the electrostatic charge distributed along the polymer chains, the presence and concentration of counter-ions play a critical role in polyelectrolyte systems. While conceptually understood for decades, experimental measurements of counter-ion concentrations have been largely limited to a relatively small set of materials that involve macroscopic samples. By developing calibration curves from frozen-hydrated buffer of known ionic strength, we measure the concentration of Na counter-ions in microgels of poly(acrylic acid) (PAA) with a limit of detection of â¼0.014 M. Such measurements may help resolve some long-standing questions in polyelectrolyte science concerning counter-ion condensation. Even in the absence of a calibration curve, we show that spatially resolved X-ray spectroscopy can map the spatial distribution of a cationic oligopeptide complexed within a hydrated PAA microgel because of the nitrogen fingerprint that, albeit at very low concentration, is unique to the peptide. We look specifically at the case of a microgel with a so-called core-shell structure, where, again, the underlying polyelectrolyte science responsible for core-shell formation remains incompletely understood. These examples highlight how a modern cryo-SEM can be exploited to quantitatively characterize hydrated soft matter. The approach is almost certain to continue its development and impact as the base of experienced practitioners, the accessibility to well-configured microscopes, and the abundance of challenging problems involving hydrated soft matter all continue to grow.
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The Mn x Ce y binary catalysts with a three-dimensional network structure were successfully prepared via a polymer-assisted deposition method using ethylenediaminetetraacetic acid and polyethyleneimine as complexing agents. The developed pore structure could facilitate the gas diffusion and accelerate the catalytic reaction for NH3 selective catalytic reduction (SCR). Moreover, the addition of Ce is beneficial for the exposure of active sites on the catalyst surface and increases the adsorption of the NH3 and NO species. Therefore, the Mn1Ce1 catalyst exhibits the best catalytic activity for NO x removal with a conversion rate of 97% at 180 °C, superior water resistance, and favorable stability. The SCR reaction over the Mn1Ce1 catalyst takes place through the E-R pathway, which is confirmed by the in situ diffuse reflectance Fourier transform analysis. This work explores a new strategy to fabricate multimetal catalysts and optimize the structure of catalysts.
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Self-defensive biomaterial surfaces are being developed in order to mitigate infection associated with tissue-contacting biomedical devices. Such infection occurs when microbes colonize the surface of a device and proliferate into a recalcitrant biofilm. A key intervention point centers on preventing the initial colonization. Incorporating antimicrobials within a surface coating can be very effective, but the traditional means of antimicrobial delivery by continuous elution can often be counterproductive. If there is no infection, continuous elution creates conditions that promote the development of resistant microbes throughout the patient. In contrast, a self-defensive coating releases antimicrobial only when and only where there is a microbial challenge to the surface. Otherwise, the antimicrobial remains sequestered within the coating and does not contribute to the development of resistance. A self-defensive surface requires a local trigger that signals the microbial challenge. Three such triggers have been identified as: (1) local pH lowering; (2) local enzyme release; and (3) direct microbial-surface contact. This short review highlights the need for self-defensive surfaces in the general context of the device-infection problem and then reviews key biomaterials developments associated with each of these three triggering mechanisms.
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The complexation of polyvalent macroions with oppositely charged polyelectrolyte microgels can lead to core-shell structures. The shell is believed to be highly deswollen with a high concentration of counter-macroions. The core is believed to be relatively free of macroions but under a uniform compressive stress due to the deswollen shell. We use cryo-scanning electron microscopy (SEM) with X-ray microanalysis to confirm this understanding. We study poly(acrylic acid) (PAA) microgels which form a core-shell structure when complexed with a small cationic antimicrobial peptide (L5). We follow the spatial distribution of polymer, water, Na counterions, and peptide based on the characteristic X-ray intensities of C, O, Na, and N, respectively. Frozen-hydrated microgel suspensions include buffers of known composition from which calibration curves can be generated and used to quantify both the microgel water and sodium concentrations, the latter with a minimum quantifiable concentration less than 0.048 M. We find that as-synthesized PAA microgels are enriched in Na relative to the surrounding buffer as anticipated from established ideas of counterion shielding of electrostatic charge. The shell in L5-complexed microgels is depleted in Na and enriched in peptide and contains relatively little water. Our measurements furthermore show that shell/core interface is diffuse over a length scale of a few micrometers. Within the limits of detection, the core Na concentration is the same as that in as-synthesized microgels, and the core is free of peptide. The core has a slightly lower water concentration than as-synthesized controls, consistent with the hypothesis that the core is under compression from the shell.
Subject(s)
Antimicrobial Cationic Peptides/chemistry , Microgels/chemistry , Polyelectrolytes/chemistry , Particle Size , Surface PropertiesABSTRACT
Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is a crucial signal transducer in both the TNFR superfamily and Toll-like receptor/interleukin 1R family. Although significant progress has been made in clarifying the role of TRAF6 in mammals, the function of TRAF6 in fish is still poorly understood. In this study, we cloned the orange-spotted grouper (Epinephelus coioides) TRAF6 (EcTRAF6) cDNA, with an open reading frame of 1713bp encoding 570 amino acids. Sequence analysis indicated that EcTRAF6 contains the four characteristic domains conserved in the TRAF family, including an N-terminal RING finger, two zinc fingers, a coiled-coil domain, and a C-terminal MATH domain. Homology alignment and phylogenetic analysis demonstrated that EcTRAF6 shares high sequence identity with TRAF6 of other fish species. The EcTRAF6 gene contains seven exons and six introns, which is similar to the organization in ayu, but not in the common carp, human, or mouse (six exons and five introns). EcTRAF6 transcripts were broadly expressed in all tissues tested, and increased after infection with Cryptocaryon irritans. Intracellular localization showed EcTRAF6 was distributed mainly in the cytoplasm. Over-expression of wild type (WT) EcTRAF6, truncated forms of EcTRAF6, including ΔZinc finger 2 and ΔMATH, and a mutant of C78A activated NF-κB strongly in HEK293T cells; whereas truncations, including ΔRING, ΔZinc finger 1 and Δcoiled-coiled, and a mutant of K132R induced the activity of NF-κB slightly compared to WT EcTRAF6, implying the latter has a more crucial role in downstream signal transduction. Together, these results suggested EcTRAF6 functions like that of mammals to activate NF-κB, and it might have an important role in host defense against parasitic infections.