Search

As a powerful and effective analytical tool, surface-enhanced Raman scattering (SERS) has attracted considerable research interest in the fields of wearable flexible sensing and non-invasive point-of-care testing (POCT) medical diagnosis. In this mini-review, we briefly summarize the design strategy, the development progress of wearable SERS sensors and its applications in this field. We present SERS substrate analysis of material design requirements for wearable sensors and highlight the benefits of novel plasmonic particle-in-cavity (PIC)-based nanostructures for flexible SERS sensors, as well as the unique interfacial adhesion effect and excellent mechanical properties of natural silk fibroin (SF) derived from natural cocoons, indicating promising futures for applications in the field of flexible electronic, optical, and electrical sensors. Additionally, SERS wearable sensors have shown great potential in the fields of different disease markers as well as in the diagnosis testing for COVID-19. Finally, the current challenges in this field are pointed out, as well as the promising prospects of combining SERS wearable sensors with other portable health monitoring systems for POCT medical diagnosis in the future.

Despite its rarity, insulinoma is the most common type of pancreatic endocrine neoplasm, with an occurrence of 1 to 5 per million per year in the population. Surgical resection or enucleation is the first line of curative treatment choice for insulinoma. Eight patients with symptomatic insulinomas treated by radiofrequency ablation have been described since 2009. In the past two years, we treated two patients with symptomatic insulinomas (one in the pancreatic tail and the other in the pancreatic neck) successfully using laparoscopic radiofrequency ablation. Both patients achieved complete elimination without any significant complications. Our study suggests laparoscopic radiofrequency ablation could be developed as a safe and effective alternative treatment to surgery for the patients with insulinomas who refuse or are not eligible for surgery.

Magnetic cellulose/Fe3O4 beads (CFBs) were fabricated by dispersing Fe3O4 particles in a microcrystalline cellulose (MCC) matrix. The CFBs were characterized by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), energy dispersive X-ray spectrometry (EDS), Brunauer–Emmett–Teller (BET) analysis and scanning electron microscopy (SEM). The adsorption behaviors of CFBs were studied by chlortetracycline hydrochloride (CTC) adsorption experiments. By means of adsorption kinetics and isotherms, the adsorption mechanisms were explored. The results show that quasi-spherical CFBs with a BET surface area as high as 119.63 m2/g were successfully tailored, with the high saturation magnetization (Ms > 40 emu/g) guaranteeing the magnetic separation of CFBs from wastewater. The process of adsorbing CTC onto CFBs involves monolayer chemical adsorption, and the maximum adsorption capacity for CTC estimated by the Langmuir model is 89.53 mg/g. The CFB product shows better adsorption performance in acidic solution than in basic solution.

In recent years, radiofrequency (RF) ablation has been increasingly used for treating hepatic hemangiomas attributing to its unique advantages, such as minimal invasiveness, definite efficacy, high safety, fast recovery, and wide applicability. However, complications related to RF ablation had been frequently reported, especially while being used for treating huge hemangioma (≥10 cm). Cautious measures had been taken to prevent the incidence of ablation-induced complications, but still unexpected complications occurred. Herein we reported a case of severe myocardial dysfunction along with systemic inflammatory response syndrome occurring immediately post RF ablation of a 10.7 cm hemangioma. This serious complication was effectively managed by supportive care with the full recovery in a short period of time.

This study investigates the rejuvenation mechanism of asphalt binders at the microscopic level and compares the rejuvenation effects of rejuvenators. A model of rejuvenated asphalt was established on the basis of molecular simulation by adding different doses of two rejuvenators to the aged asphalt. This model was validated in terms of density and surface free energy. The diffusion ability of the rejuvenator was investigated by using a diffusion model and mean square displacement. The deagglomeration ability of rejuvenators on asphaltene was explored by using a radial distribution function. The microscopic mechanism of asphalt rejuvenation was explained. Results show that small molecule structures are more diffusible than long-chain structures, and aromatic ring structures are more attracted than polar functional groups. The rejuvenating effect of the rejuvenator was evaluated in terms of viscosity and cohesive energy density. Results show that the long-chain structure reduces the viscosity value more than the small molecule structure. The aromatic ring structure in the aged asphalt helps to restore the compatibility between the fractions. This study serves as a guide for the selection and development of future rejuvenators.

Abstract Background The mechanism regarding rapid progression of residual hepatocellular carcinoma (HCC) after insufficient radiofrequency ablation (RFA) has been preliminarily discussed. However, most studies have mainly focused on RFA-induced changes in the tumor cells. The present study was designed to determine whether tumor-associated endothelial cells (TAECs) could contribute to the invasiveness of HCC after insufficient RFA. Methods TAECs were isolated from fresh HCC tissue and characterized. Morphological changes were observed in TAECs after heat treatment for 10 min. TAEC proliferation, migration and tube formation after heat treatment for 10 min at 37°C (control group), and 42 and 47°C (insufficient RFA groups) were examined. The differences in TAECs interactions with HepG2-GFP or HCCLM3-GFP cells among the two insufficient RFA groups and control group were evaluated. The expression of E-selectin, ICAM-1 and VCAM-1 in TAECs was measured. The effects of TAECs on the invasiveness of HepG2-GFP or HCCLM3-GFP cells after insufficient RFA were analyzed. The IL-6, IL-8, MCP-1 and GRO-α concentrations in conditioned medium from TAECs were measured after insufficient RFA. The associated signaling pathways of Akt, ERK1/2, STAT3 and NF-κB were analyzed in TAECs after insufficient RFA. Results TAECs expressed the EC-specific markers and took up complexes of Dil-Ac-LDL. Relative to the control group, the proliferation of TAECs was significantly inhibited and their migration and tube formation were significantly enhanced in the insufficient RFA groups. Significantly more HepG2-GFP or HCCLM3-GFP cells adhered to TACEs in these groups than in the control group (all PP Conclusions Insufficient RFA enhanced TAEC migration and tube formation, and this may play a key role in the rapid growth of residual HCC. Increased expression of metastasis-related molecules in TAECs after insufficient RFA may be a potential mechanism for the metastasis of residual HCC.

Abstract Background Rapid progression of residual tumor after radiofrequency ablation (RFA) of hepatocellular carcinoma has been observed increasingly. However, its underlying mechanisms remain to be clarified. The present study was designed to determine whether low temperature of RFA at the target sites facilitates rapid progression of residual hepatic VX2 carcinoma and to clarify the possible underlying mechanisms. Methods The residual VX2 hepatoma model in rabbits was established by using RFA at 55, 70 and 85°C. Rabbits that were implanted with VX2 hepatoma but did not receive RFA acted as a control group. The relationship between rapid progression of residual hepatic VX2 carcinoma and low temperature of RFA at the target sites was carefully evaluated. A number of potential contributing molecular factors, such as proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 9 (MMP-9), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF) and Interleukin-6 (IL-6) were measured. Results The focal tumor volume and lung metastases of RFA-treated rabbits increased significantly compared with the control group (P < 0.05), and the greatest changes were seen in the 55°C group (P < 0.05). Expression of PCNA, MMP-9, VEGF, HGF and IL-6 in tumor tissues increased significantly in the RFA-treated groups compared with the control group, and of the increases were greatest in the 55°C group (P < 0.05). These results were consistent with gross pathological observation. Tumor re-inoculation experiments confirmed that low temperature of RFA at the target sites facilitated rapid progression of residual hepatic VX2 carcinoma. Conclusions Insufficient RFA that is caused by low temperature at the target sites could be an important cause of rapid progression of residual hepatic VX2 carcinoma. Residual hepatic VX2 carcinoma could facilitate its rapid progression through inducing overexpression of several molecular factors, such as PCNA, MMP-9, VEGF, HGF and IL-6.

Two-dimensional electron gas is precisely confined at the interface of insulating oxide thin films and substrates, e.g., LaAlO3/SrTiO3(STO) and, thus, shows 2D electronic transport features. Here, we report a high mobility electron state at the interface of a Cr2O3 film and a STO substrate, which is realized by depositing a Cr film onto a STO (111) substrate in high vacuum (1 × 10−10 mbar) using molecular beam epitaxy. At a substrate temperature of 700 °C, the deposited Cr films capture oxygen atoms from STO substrates, resulting in the formation of an insulating Cr2O3 layer and an oxygen-deficient STO layer. Due to the presence of high mobility electrons [1.5 × 104 cm2V−1 s−1 at 1.8 K] at the Cr2O3/STO interface, both out-of-plane and in-plane Shubnikov–de Haas oscillations are observed at low temperatures (<3 K), which suggests that the highly conducting electron gas has extended into the STO bulk along the thickness direction with a certain depth to allow electrons to complete the cyclotron motion. [ABSTRACT FROM AUTHOR]

Investigating the carbonate preservation efficiency (CPE) of continental crust is crucial to understand the global carbon cycle, which requires constraints on initial carbonate abundances (ICAs) of crustal rocks. To link Mg isotopes to ICAs, we present elemental and Mg isotopic data for Himalayan carbonate‐bearing and carbonate‐free metasedimentary rocks. Given no evident melt extraction or external‐fluid infiltration, ICAs of these samples can be independently estimated by elemental data. Despite different carbonate species in the protoliths, all the samples show congruent relationship between their δ26Mg and ICAs, owing to the elevated carbonate δ26Mg and Mg/Ca in protoliths of calcite‐rich samples resulting from diagenetic processes. When collated with literature data, we suggest the observed correlation here can be applied to most carbonate‐bearing (meta‐)sedimentary rocks. Based on a steady state box‐model, we constrained the modern net carbonate accretion flux (9.50−5.56+9.50 ${9.50}_{-5.56}^{+9.50}$ Tmol/year) and the average time‐integrated CPE (∼80−43+20 ${80}_{-43}^{+20}$%) for continental crust. Plain Language Summary: Investigating the fate of carbonate preserved in continental crust is fundamental for understanding its role playing in the global carbon cycle, but is hindered by the lack of knowledge about the initial carbonate abundance of metasedimentary rocks prior to modification (e.g., anatexis). By analyzing Himalayan metasedimentary rocks, here we show a congruent relationship between their δ26Mg and initial carbonate abundances, irrespective of their protolith carbonate species, and suggest it is applicable to most carbonate‐bearing (meta‐)sedimentary rocks. Based on this relationship, the carbonate preservation in continental crust was simulated using a steady state box‐model. The results indicate a very high carbonate accretion influx to the continental crust, seven times higher than the C degassing flux in the mid‐ocean ridge. Considering explosive degassing of the accreted carbonates during episodic tectonomagmatic events, the continental crust could have been an important driving force for regulating the atmospheric CO2 during Earth's history. Key Points: A strong correlation between bulk δ26Mg of carbonate‐bearing metasedimentary rocks and their initial carbonate abundances was establishedDespite different carbonate species in protoliths, both the calcite‐rich and dolomite‐rich samples show nearly identical correlationsSteady state box‐model on the carbonate preservation efficiency of continent indicates it is a notable force to regulate atmospheric CO2 [ABSTRACT FROM AUTHOR]

The distribution of Mg isotopes in minerals is becoming increasingly relevant in Earth science. Usually, they are determined by dissolving mineral concentrates and, after purifying Mg with ion exchange resins, analysing the resulting solutions by TIMS or, most often, MC‐ICP‐MS. When applied to individual minerals, these methods are slow and prone to contamination from impurities in the concentrates, inconveniences that may be avoided using spot analysis techniques such as LA‐MC‐ICP‐MS or SIMS, albeit at the price of a large instrumental mass fractionation (IMF) and isobaric interferences, most prominent in the former. Here, we studied the potential of the multi‐collector SHRIMP II ion microprobe for measuring Mg isotopes in Fe‐Mg silicates and oxides. We found that, when corrected for the divergence of the Mg ion paths within the sample chamber caused by the Earth's magnetic field, the SHRIMP's IMF overwhelmingly depends on the mineral species, and the effects of variable chemical composition are negligible. We propose that the IMF is caused by the force constant difference, ∆F, between "hard" and "soft" bonds linking the ions of the studied element to the mineral lattice. Given that ∆F is a constant for each mineral species, we calculated IMF‐correction factors for the most common Mg‐bearing minerals. The thus‐calculated correction factors permit the analysis in the same session, and with reasonable accuracy (within ~ 0.3‰ of the δ26Mg determined by SN‐MC‐ICP‐MS analyses of concentrates), of samples from different mineral species, facilitating the application of Mg isotopes to terrestrial studies. [ABSTRACT FROM AUTHOR]