Chitosan Biguanidine/PVP Antibacterial Coatings for Perishable Fruits.

World hunger is on the rise, yet one-third of food is wasted. It is necessary to develop an effective food preservation method to reduce food waste. This article reports a composite film based on chitosan biguanidine hydrochloride(CBg) and poly (N-vinyl-2-pyrrolidone)(PVP) that can be used as a conformal coating for fresh produce. Due to the strong positive charge of CBg, the film has excellent antibacterial properties. Owing to the hydrogen bonds between CBg and PVP, the film has good flexibility and mechanical properties. In addition, the coating is washable, transparent, and can reduce the evaporation of water. The above characteristics mean the film has broad application prospects in the field of food preservation.

Recent Progress in Intelligent Wearable Sensors for Health Monitoring and Wound Healing Based on Biofluids.

The intelligent wearable sensors promote the transformation of the health care from a traditional hospital-centered model to a personal portable device-centered model. There is an urgent need of real-time, multi-functional, and personalized monitoring of various biochemical target substances and signals based on the intelligent wearable sensors for health monitoring, especially wound healing. Under this background, this review article first reviews the outstanding progress in the development of intelligent, wearable sensors designed for continuous, real-time analysis, and monitoring of sweat, blood, interstitial fluid, tears, wound fluid, etc. Second, this paper reports the advanced status of intelligent wound monitoring sensors designed for wound diagnosis and treatment. The paper highlights some smart sensors to monitor target analytes in various wounds. Finally, this paper makes conservative recommendations regarding future development of intelligent wearable sensors.

An injectable and biodegradable nano-photothermal DNA hydrogel enhances penetration and efficacy of tumor therapy.

The biological barrier of solid tumors hinders deep penetration of nanomedicine, constraining anticancer treatment. Moreover, the inherent multidrug resistance (MDR) of cancer tissues may further limit the efficacy of anti-tumor nanomedicine. We synthesized highly permeable, photothermal, injectable, and positively charged biodegradable nucleic acid hydrogel (DNA-gel) nanoparticles to deliver cancer drugs. The nanoparticles are derived from photothermal materials containing black phosphorus quantum dots (BPQDs). The intra-tumoral BPQDs improve the sensitivity of tumor cells to photothermal therapy (PTT) and photodynamic treatment (PDT). Tumor cells take up the positively charged and controllable size DNA-gel nanoparticles, facilitating easy penetration and translocation of the particles across and within the cells. Mouse models demonstrated the anti-tumor activity of the DNA gel nanoparticles in vivo. In particular, the DNA gel nanoparticles enhanced clearance of both small and large tumor masses. Just 20 days after treatment, the tumor masses had been cleared. Compared to DOX chemotherapy alone, the DNA-gel treatment also significantly reduced drug resistance and improved the overall survival of mice with orthotopic breast tumors (83.3%, 78 d). Therefore, DNA gel nanoparticles are safe and efficient supplements for cancer therapy.

Functional DNA-based hydrogel intelligent materials for biomedical applications.

Deoxyribonucleic acid (DNA) nanotechnology is a relevant research field of nano-biotechnology, which has developed rapidly in recent years. Researchers have studied DNA far more than they have studied its genetic characteristics, and now it has evolved into the field of nanomedical materials. A variety of articles based on DNA nanostructures can be obtained by rational design and controllable preparation. In particular, intelligent DNA-based hydrogel materials have attracted significant attention as an essential representative of macro DNA materials. They have shown a wide range of applications, especially in the field of biomedical applications. DNA-based hydrogels have many unique and fascinating properties, such as, excellent biocompatibility, biodegradability, basic programmability, catalytic activities, therapeutic potential, and molecular recognition and bonds. The intelligent DNA hydrogel will undergo abrupt changes in the stimulation of temperature, pH value, ionic strength, and solvent composition. These factors can also be used for applications in intelligent materials that play an essential role in biomedical sciences. To date, intelligent DNA hydrogels have been reported for many applications, including controlled drug delivery, targeted gene therapy, cancer therapy, biosensors, protein production, and 3D cell cultures. However, the large-scale production of intelligent DNA hydrogels has not yet been realized, and the synergistic multifunctional integration has not been explored. This review summarizes the current state of DNA nanostructures, especially the intelligent DNA-based hydrogel materials, and focuses on design and engineering for bio-responsive use and proposes some reasonable prospects for the future development of intelligent DNA-based hydrogel materials.

CT combined with tumor markers in the diagnosis and prognosis of hepatocellular carcinoma.

PURPOSE: To investigate the application values of CT combined with tumor markers (TM) in the diagnosis and prognosis of hepatocellular carcinoma (HCC). METHODS: 62 HCC patients were selected as the study group and all of them had undergone hepatectomy. In addition, 40 healthy subjects composed the control group. Blood samples were collected preoperatively from the subjects of the study group, and serum alpha fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) levels were determined by radioimmunoassay. The correlation between serum TM levels and clinicopathological features was investigated by pathological examination. The imaging features of HCC were explored by spiral CT plain scanning and enhanced scanning. The diagnostic efficiency of single detection of TM, combined detection of TMs and combined detection of TMs and CT was analyzed by receiver operating characteristic (ROC). RESULTS: The levels of serum AFP, CA19-9 and CEA in HCC patients were significantly higher than those in the control group (p<0.05). Patients with low differentiation and distant metastasis had higher levels of AFP, CA19-9 and CEA (p<0.05) compared with patients with high differentiation and no distant metastasis. There were no significant differences in TM levels in HCC patients with different age, gender and clinical stages (p>0.05). The ROC analysis showed that the single detection of serum AFP, CEA or CA19-9 had lower specificity and sensitivity compared with the combined detection of the three TMs (p<0.05). The combined CT examination could achieve a specificity of 95.71% and a sensitivity of 87.47%, superior to the combined detection of the TMs (p<0.05). Eight HCC patients relapsed within 6 months after operation. Compared with those before operation, the levels of serum AFP, CA19-9 and CEA in the relapsed patients were increased significantly, and the TM levels were higher than those in patients without relapse (p<0.05). CONCLUSIONS: The detection of serum AFP, CA19-9 and CEA combined with CT can overcome the deficiency of single detection, avoid misdiagnosis and missed diagnosis, and increase significantly the positive detection rate of HCC.