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Image-guided thermal ablation (TA), which is less invasive, has been widely applied for treating various kinds of tumors. However, TA still poses the potential risk of thermal damage to sensitive tissue nearby. Therefore, an adjunctive thermoprotective hydrodissection technique with constant injection of 5% glucose (5% Glu) has currently been adopted for clinical application, but this may be hazardous to humans. In this study, a multifunctional hyaluronic acid-based hydrogel (HA-Dc) was developed for hydrodissection. Compared with 5% Glu (the most clinically used solution) and the previously reported F127 hydrogel, the HA-Dc hydrogel was studied in vitro in a porcine liver model and in vivo in a rabbit model and showed good injectability and better tissue retention, stability, and thermoprotective properties throughout the TA procedure. Furthermore, in the preclinical evaluation in a Macaca fascicularis (M. fascicularis) model, HA-Dc showed excellent performance in terms of stricter neuroprotection compared with 5% Glu. In addition, the HA-Dc hydrogel with good biocompatibility and controllable degradation behavior in vivo could be a promising platform for thermal protection during clinical TA procedures.

The reservoir properties of super-heavy oil reservoirs in fluvial sedimentation are relatively poor, with high heterogeneity directly affecting the steam injection rate and expansion velocity of the steam chamber in the SAGD process. In order to significantly improve SAGD production performance, a combination of laboratory testing and physical simulation experiments was used to analyze the changes in reservoir-rock structure, rock geomechanical characteristics, and porosity and permeability during high-pressure injection, through rock geomechanics testing, core-flood experiment, and SEM scanning analysis. Large-scale two-dimensional physical simulation experiments were designed to analyze the effect of different injection agents in assisting the expansion of steam chambers. The experimental results showed that, with the increase in injection pore pressure, the reservoir permeability increased from 2.74 D to 4.56 D, and the contact between rock particles became looser after expansion, indicating a significant improvement in reservoir properties through high-pressure-injection-induced dilation. The results of the two-dimensional physical simulation experiments demonstrated that the solvent-assisted steam-chamber dilation speed was further increased compared with the conventional huff-n-puff dilation. Cyclic gas-injection volume can be increased from 0.16 PV in pure-steam injection cases to 0.32 PV. The hybrid-agent system of solvent-plus-gas can produce the dual positive effect of solvent dissolution and gas diffusion, more effectively improve the steam-chamber expansion speed, enhance the phased oil-recovery degree by 23.41%, and increase the oil/steam ratio from 0.27 to 0.33, indicating encouraging potentials in improving heavy oil and bitumen production performance by the dilation strategy.

Biofilms are closely associated with the tough healing and dysfunctional inflammation of chronic wounds. Photothermal therapy (PTT) emerged as a suitable alternative which could destroy the structure of biofilms with local physical heat. However, the efficacy of PTT is limited because the excessive hyperthermia could damage surrounding tissues. Besides, the difficult reserve and delivery of photothermal agents makes PTT hard to eradicate biofilms as expectation. Herein, we present a GelMA-EGF/Gelatin-MPDA-LZM bilayer hydrogel dressing to perform lysozyme-enhanced PTT for biofilms eradication and a further acceleration to the repair of chronic wounds. Gelatin was used as inner layer hydrogel to reserve lysozyme (LZM) loaded mesoporous polydopamine (MPDA) (MPDA-LZM) nanoparticles, which could rapidly liquefy while temperature rising so as to achieve a bulk release of nanoparticles. MPDA-LZM nanoparticles serve as photothermal agents with antibacterial capability, could deeply penetrate and destroy biofilms. In addition, the outer layer hydrogel consisted of gelatin methacryloyl (GelMA) and epidermal growth factor (EGF) promoted wound healing and tissue regeneration. It displayed remarkable efficacy on alleviating infection and accelerating wound healing in vivo. Overall, the innovative therapeutic strategy we came up with has significant effect on biofilms eradication and shows promising application in promoting the repair of clinical chronic wounds.

Abstract The enzyme-mediated elevation of reactive oxygen species (ROS) at the tumor sites has become an emerging strategy for regulating intracellular redox status for anticancer treatment. Herein, we proposed a camouflaged bionic cascaded-enzyme nanoreactor based on Ti3C2 nanosheets for combined tumor enzyme dynamic therapy (EDT), phototherapy and deoxygenation-activated chemotherapy. Briefly, glucose oxidase (GOX) and chloroperoxidase (CPO) were chemically conjugated onto Ti3C2 nanosheets, where the deoxygenation-activated drug tirapazamine (TPZ) was also loaded, and the Ti3C2-GOX-CPO/TPZ (TGCT) was embedded into nanosized cancer cell-derived membrane vesicles with high-expressed CD47 (meTGCT). Due to biomimetic membrane camouflage and CD47 overexpression, meTGCT exhibited superior immune escape and homologous targeting capacities, which could effectively enhance the tumor preferential targeting and internalization. Once internalized into tumor cells, the cascade reaction of GOX and CPO could generate HClO for efficient EDT. Simultaneously, additional laser irradiation could accelerate the enzymic-catalytic reaction rate and increase the generation of singlet oxygen (1O2). Furthermore, local hypoxia environment with the oxygen depletion by EDT would activate deoxygenation-sensitive prodrug for additional chemotherapy. Consequently, meTGCT exhibits amplified synergistic therapeutic effects of tumor phototherapy, EDT and chemotherapy for efficient tumor inhibition. This intelligent cascaded-enzyme nanoreactor provides a promising approach to achieve concurrent and significant antitumor therapy.

Some physical processes such as oil and gas development, metal deposit collection, and groundwater resource migration can cause density changes, for which microgravity monitoring is the most intuitive method to monitor the density change process. Based on the basic principle of microgravity measurement and the idea of multiscale separation, a multiscale, second-order, surface-fitting, residual gravity anomaly extraction method is proposed to separate superimposed microgravity fields. In this method, regional fields of different scales are fitted and calculated successively with the measurement points as the center, so as to separate the gravity anomalies produced by different-depth density bodies. Results from actual data show that this method extracts the reservoir’s residual density characteristics of plane gravity anomaly on the basis of remaining oil distribution characteristics, consistent with reservoir numerical simulation results. A three-dimensional least-squares inversion of the method for extracting residual gravity anomaly was carried out, with the inversion results consistent with the results of vertical remaining oil distribution characteristics and well-test production results.

Abstract Metastatic peritoneal carcinoma (mPC) is a deadly disease without effective treatment. To improve treatment of this disease, a recently developed hyperthermic intraperitoneal chemotherapy (HIPEC) has emerged as the standard of care. However, the efficacy of this approach is limited by inefficient drug penetration and rapidly developed drug resistance. Herein, a nanotechnology approach is reported that is designed to improve drug delivery to mPC and to augment the efficacy of HIPEC through delivery of chemoimmunotherapy. First, the drug delivery efficiency of HIPEC is determined and it is found that chemotherapy agents cannot be efficiently delivered to large tumors nodules. To overcome the delivery hurdle, genetically engineered exosomes‐thermosensitive liposomes hybrid NPs, or gETL NPs, are then synthesized, and it is demonstrated that the NPs after intravenous administration efficiently penetrates into mPC tumors and releases payloads at the hypothermia condition of HIPEC. Last, it is shown that, when granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) and docetaxel are co‐delivered, gETL NPs effectively inhibit tumor development and the efficacy is enhanced when HIPEC is co‐administered. The study provides a strategy to improve drug delivery to mPCs and offers a promising approach to improve treatment of the disease through combination of locoregional delivery of HIPEC and systemic delivery of chemoimmunotherapy via gETL NPs.

Background: Many animal experimental studies showed that abdominal tumor cells will be widely spread during laparoscopic treatment and grow into metastases. These results are different from clinical observations. There is a hypothesis that too much tumor cells was injected in the animals lead to the results of theses bias. We aim to learn the difference of abdominal cavity volume between human body and the nude mice and to determine reasonable amount of tumor cells in the animal experiments. Methods: The insufflated CO2 volume which represents the capacity of the abdominal cavity was recorded during laparoscopic process in 212 patients and 20 nude mice respectively, the relative volume of nude mice and human body was calculated.Based on data from the literature and this study , the amount of tumor cells in the animal experiments was determined.According to these data, we set up a new animal model and a traditional one respectively,and compared the rate of successful modeling and tumor formation between two animal models. Results: The intraperitoneal volumes of humans and nude mice were 3.01±0.36 L and 0.011±0.001 L respectively.The number of tumor cells that be uesd in animal should be approximately 0.26×105 in terms of known data in human beings.Compared with the traditional animal model which formed a large number of intraperitoneal tumor metastasis, the new animal model was shows more moderately,and the rate of successful modeling was similar. Conclusion: In animal experiments, to simulate the clinical situation, about 0.26×105 tumor cells should be inject in peritoneal cavity of the nude mice., (Creative Commons Attribution License)