A graphene field-effect transistor (gFET) was non-covalently functionalised with 1-pyrenebutyric acid N-hydroxysuccinimide ester and conjugated with anti-CD63 antibodies for the label-free detection ...of exosomes. Using a microfluidic channel, part of a graphene film was exposed to solution. The change in electrical properties of the exposed graphene created an additional minimum alongside the original Dirac point in the drain-source current (I
) - back-gate voltage (V
) curve. When phosphate buffered saline (PBS) was present in the channel, the additional minimum was present at a V
lower than the original Dirac point and shifted with time when exosomes were introduced into the channel. This shift of the minimum from the PBS reference point reached saturation after 30 minutes and was observed for multiple exosome concentrations. Upon conjugation with an isotype control, sensor response to the highest concentration of exosomes was negligible in comparison to that with anti-CD63 antibody, indicating that the functionalised gFET can specifically detect exosomes at least down to 0.1 μg/mL and is sensitive to concentration. Such a gFET biosensor has not been used before for exosome sensing and could be an effective tool for the liquid-biopsy detection of exosomes as biomarkers for early-stage identification of diseases such as cancer.
The pathogenesis of tendinopathy and the primary biological change in the tendon that precipitates pathology have generated several pathoaetiological models in the literature. The continuum model of ...tendon pathology, proposed in 2009, synthesised clinical and laboratory-based research to guide treatment choices for the clinical presentations of tendinopathy. While the continuum has been cited extensively in the literature, its clinical utility has yet to be fully elucidated. The continuum model proposed a model for staging tendinopathy based on the changes and distribution of disorganisation within the tendon. However, classifying tendinopathy based on structure in what is primarily a pain condition has been challenged. The interplay between structure, pain and function is not yet fully understood, which has partly contributed to the complex clinical picture of tendinopathy. Here we revisit and assess the merit of the continuum model in the context of new evidence. We (1) summarise new evidence in tendinopathy research in the context of the continuum, (2) discuss tendon pain and the relevance of a model based on structure and (3) describe relevant clinical elements (pain, function and structure) to begin to build a better understanding of the condition. Our goal is that the continuum model may help guide targeted treatments and improved patient outcomes.
A novel WS2–graphite dual-ion battery (DIB) is developed by combining a conventional graphite cathode and a high-capacity few-layer WS2-flake anode. The WS2 flakes are produced by exploiting wet-jet ...milling (WJM) exfoliation, which allows large-scale and free-material loss production (i.e., volume up to 8 L h−1 at concentration of 10 g L−1 and exfoliation yield of 100%) of few-layer WS2 flakes in dispersion. The WS2 anodes enable DIBs, based on hexafluorophosphate (PF6 –) and lithium (Li+) ions, to achieve charge-specific capacities of 457, 438, 421, 403, 295, and 169 mAh g–1 at current rates of 0.1, 0.2, 0.3, 0.4, 0.8, and 1.0 A g–1, respectively, outperforming conventional DIBs. The WS2-based DIBs operate in the 0 to 4 V cell voltage range, thus extending the operating voltage window of conventional WS2-based Li-ion batteries (LIBs). These results demonstrate a new route toward the exploitation of WS2, and possibly other transition-metal dichalcogenides, for the development of next-generation energy-storage devices.
Hot-carriers, that is, charge carriers with an effective temperature higher than that of the lattice, may contribute to the high power conversion efficiency (PCE) shown by perovskite-based solar ...cells (PSCs), which are now competitive with silicon solar cells. Hot-carriers lose their excess energy in very short times, typically in a few picoseconds after excitation. For this reason, the carrier dynamics occurring on this time scale are extremely important in determining the participation of hot-carriers in the photovoltaic process. However, the stability of PSCs over time still remains an issue that calls for a solution. In this work, we demonstrate that the insertion of graphene flakes into the mesoscopic TiO2 scaffold leads to stable values of carrier temperature. In PSCs aged over 1 week, we indeed observe that in the graphene-free perovskite cells the carrier temperature decreases by about 500 K from 1800 to 1300 K, while the graphene-containing cell shows a reduction of less than 200 K after the same aging time delay. The stability of the carrier temperature reflects the stability of the perovskite nanocrystals embedded in the mesoporous graphene-TiO2 layer. Our results, based on femtosecond transient absorption measurements, show that the insertion of graphene can be beneficial for the design of stable PSCs with the aim of exploiting the hot-carrier contribution to the PCE of the PSCs.
Regioregular poly(3-hexylthiophene-2,5-diyl) (rr-P3HT), the workhorse of organic photovoltaics, has been recently exploited in bulk heterojunction (BHJ) configuration with phenyl-C61-butyric acid ...methyl ester (PCBM) for solution-processed hydrogen-evolving photocathodes, reaching cathodic photocurrents at 0 V vs RHE (J 0 V vs RHE) of up to 8 mA cm–2. The photoelectrochemical performance of these photocathodes strongly depends on the presence of the electron- (ESL) and hole- (HSL) selective layers. While TiO2 and its substoichiometric phases are consolidated ESL materials, the currently used HSLs (e.g., MoO3, CuI, PEDOTT:PSS, WO3) suffer electrochemical degradation under hydrogen evolution reaction (HER) working conditions. In this work, we use solution-processed graphene derivatives as HSL to boost the efficiency and durability of rr-P3HT:PCBM-based photocathodes, demonstrating record-high performance. In fact, our devices show cathodic J 0 V vs RHE of 6.01 mA cm–2, onset potential (V o) of 0.6 V vs RHE, ratiometric power-saved efficiency (φsaved) of 1.11%, and operational activity of 20 h in 0.5 M H2SO4 solution. Moreover, the designed photocathodes are effectively working in different pH environments ranging from acidic to basic. This is pivotal for their exploitation in tandem configurations, where photoanodes operate only in restricted electrochemical conditions. Furthermore, we demonstrate the scalability of our all-solution-processed approach by fabricating a large-area (∼9 cm2) photocathode on flexible substrate, achieving a remarkable cathodic J 0 V vs RHE of 2.8 mA cm–2, V o of 0.45 V vs RHE, and φsaved of 0.31%. This is the first demonstration of highly efficient rr-P3HT:PCBM flexible photocathodes based on low-cost and solution-processed manufacturing techniques.
Methods: Protocol study design. Intra and inter-rater reliability will be analysed through an Intraclass Correlation Coefficient (ICC) analysis using SPSS software. The findings of this study may ...contribute to clinical practice in many fields, to provide greater detail around clinical conditions where we have no gold standard of differential diagnosis.
Nanomaterials may be contaminated with bacterial endotoxin during production and handling, which may confound toxicological testing of these materials, not least when assessing for immunotoxicity. In ...the present study, we evaluated the conventional Limulus amebocyte lysate (LAL) assay for endotoxin detection in graphene based material (GBM) samples, including graphene oxide (GO) and few-layered graphene (FLG). Our results showed that some GO samples interfered with various formats of the LAL assay. To overcome this problem, we developed a TNF-α expression test (TET) using primary human monocyte-derived macrophages incubated in the presence or absence of the endotoxin inhibitor, polymyxin B sulfate, and found that this assay, performed with non-cytotoxic doses of the GBM samples, enabled unequivocal detection of endotoxin with a sensitivity that is comparable to the LAL assay. FLG also triggered TNF-α production in the presence of the LPS inhibitor, pointing to an intrinsic pro-inflammatory effect. Finally, we present guidelines for the preparation of endotoxin-free GO, validated by using the TET.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objective
The increased prevalence of childhood metabolic syndrome (MetS) is a public health issue. It has been shown that a dysregulated bile acid (BA) profile could be involved in the development ...of MetS, in which the gut microbiota could have a significant role in BA levels. This study aimed to evaluate differences in serum BA levels in children with and without MetS and whether these levels were associated with gut microbial composition.
Methods
A total of 100 children aged 10 to 12 years were enrolled in this study, 42 children with MetS (cases) and 58 control participants. Serum BAs were measured by liquid chromatography‐tandem mass spectrometry and gut microbiota was determined by 16S ribosomal RNA gene sequencing.
Results
Children with MetS showed higher levels of total, secondary, and 12α‐hydroxylated BAs, as well as deoxycholic acid, and these were associated with dyslipidemia and insulin resistance markers. Interestingly, total BAs were negatively correlated with gut bacterial diversity (Shannon index: rho = −0.218, p = 0.035), whereas total, 12α‐hydroxylated, and secondary BAs, as well as deoxycholic acid, showed negative correlations with genera known for their potential health effects, including Bifidobacterium, Akkermansia, and Faecalibacterium.
Conclusions
This study suggests that childhood MetS is associated with a dysregulated BA pool and that these alterations could influence the abundance of potentially beneficial bacteria, thus contributing to gut microbial dysbiosis.
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