A hyaluronic acid hydrogel as a mild photothermal antibacterial, antioxidant, and nitric oxide release platform for diabetic wound healing.

Hyaluronic acid (HA)-based biopolymer hydrogels are promising therapeutic dressings for various wounds but still underperform in treating diabetic wounds. These wounds are extremely difficult to heal and undergo a prolonged and severe inflammatory process due to bacterial infection, overexpression of reactive oxygen species (ROS), and insufficient synthesis of NO. In this study, a dynamic crosslinked hyaluronic acid (HA) hydrogel dressing (Gel-HAB) loaded with allomelanin (AMNP)-N, N'-dis-sec-butyl-N, N'-dinitroso-1, 4-phenylenediamine (BNN6) nanoparticles (AMNP-BNN6) was developed for healing diabetic wounds. The dynamic acylhydrazone bond formed between hydrazide-modified HA (HA-ADH) and oxidized HA (OHA) makes the hydrogel injectable, self-healing, and biocompatible. The hydrogel, loaded with AMNP-BNN6 nanoparticles, exhibits promising ROS scavenging ability and on-demand release of nitric oxide (NO) under near-infrared (NIR) laser irradiation to achieve mild photothermal antibacterial therapy (PTAT) (∼ 48 °C). Notably, the Gel-HAB hydrogel effectively reduced the oxidative stress level, controlled infections, accelerated vascular regeneration, and promoted angiogenesis, thereby achieving rapid healing of diabetic wounds. The injectable self-healing nanocomposite hydrogel could serve as a mild photothermal-enhanced antibacterial, antioxidant, and nitric oxide release platform for the treatment of diabetic wounds.

Hyaluronic acid-based multifunctional bio-active coating integrated with cinnamaldehyde/hydroxypropyl-ß-cyclodextrin inclusion complex for fruit preservation.

Natural preservatives such as cinnamaldehyde (CIN) are garnering increasing interest to replace their synthetic counterparts in maintaining fruit freshness and safety. However, their long-term effectiveness and widespread application have been greatly limited due to high volatility and potent aroma. To address these challenges, we developed a viable and simple strategy to prepare a multifunctional active coating for fruit preservation by incorporating host-guest inclusion complex of CIN and 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) CIN@HP-ß-CD into hyaluronic acid (HA), a natural polysaccharide with exceptional film-forming properties. The as-prepared HA/CIN@HP-ß-CD coatings exhibited universal surface affinity, excellent antimicrobial performance, and satisfactory antioxidant properties with no potential toxicity. Release kinetic studies have demonstrated that CIN in the coating is continuously and slowly released. Furthermore, freshness preservation experiments on bananas and fresh-cut apples demonstrated that the developed coating is effective in preserving the color of fruit, decreasing the weight loss rate, preventing the microorganism's growth, and significantly extending the period of freshness, exhibiting the potential for application in fruit preservation.

Characterization of moisture migration and diffusion in two types of tobacco biomass during the dehydration process by the TG-NMR analysis.

The tobacco waste generated from the tobacco agriculture and industry, including the discarded stem and leaf, often needs dehydration pretreatment before thermal conversion utilization. In order to study the water activity and migration of tobacco waste during the pretreatment process, TG-NMR (Thermogravimetric Nuclear Magnetic Resonance) was used to obtain the drying curves and LF-NMR (Low Field Nuclear Magnetic Resonance) T2 inversion spectrum at each stage of tobacco drying. Meanwhile, the variation pattern of pore distribution during the dehydration process of two types of tobacco waste has been obtained. Combined with the pore distribution changes, a possible spatial migration mode of water was proposed. The change of adsorption energy of water during tobacco drying was calculated, and verified the above hypothesis. This study results provide reference for the optimization of dehydration pretreatment process for different tobacco waste in order to reduce energy consumption during recycling of tobacco biomass.

Aspercitrininone A, novel antibacterial polyketide featuring unusual spiral skeleton from Aspergillus cristatus.

Aspercitrininone A (1), a novel polyketide featuring an unprecedented tetracyclic 6/6/6/5 spiral skeleton, was obtained from the rice fermentation cultures of the fungus Aspergillus cristatus together with five known compounds (2-6). Their structures were determined by HRESIMS data, 1D and 2D NMR spectroscopic analysis, and electronic circular dichroism (ECD) calculations. Aspercitrininone A was revealed as a new type of C/D cycle spiral structure and an unusual addition product of o-quinoid form citrinin with 2-methylterrefuranone. Compounds 1, 4, and 5 exhibited potent antibacterial activities with minimal inhibitory concentration (MIC) values from 13.2 to 67.3 µg/mL against four strains of human pathogenic bacteria in vitro.

Development of mussel-inspired chitosan-derived edible coating for fruit preservation.

Fruit rotting at the postharvest stage severely limits their marketing supply chains and shelf-life. Thus, developing a green and cost-effective approach to extend the shelf-life of perishable foods is highly desired. In this study, inspired by the mussel-adhesion strategy, a multifunctional fruit coating material has been developed using a quaternized catechol-functionalized chitosan (CQ-CS) grafted with 2, 3-epoxypropyl trimethyl ammonium chloride and 3, 4-dihydroxy benzaldehyde. The as-prepared CQ-CS coating exhibited excellent mechanical properties, universal surface adhesion abilities, antimicrobial and antioxidant capacities without any potential toxicity effects. Using strawberry and banana as model fruits, we showed that the CQ-CS coating could effectively maintain the fruit's firmness and color, decrease the weight loss rate, and prevent microbial growth, thus finally extending their shelf- life when compared to uncoated samples, indicating the universal application of the as-prepared CQ-CS coating. These findings demonstrated that this novel conformal coating of CQ-CS has great potential for fruit preservation in the food industry.

[Clonal analysis of endometriotic lesions using human androgen receptor gene].

OBJECTIVE: To investigate characteristics of endometriotic lesions clone with various pathological subtypes by analyzing the polymorphism of X chromosome linked human androgen receptor allele (HUMARA). METHODS: Eight frozen tissues of endometriotic leisons were collected from 6 patients who received laparotomy or laparoscopy surgery in Peking Union Medical College Hospital from Nov. 2008 to Jun. 2009. Fifty specimens of epithelial cells from single endometrial glands were isolated and collected from endometriotic lesions by using laser capture microdissection. HUMARA was applied as the gene marker of clonal analysis. Nested polymerase chain reaction, double-enzyme digestion reaction with two methylation-sensitive restriction endonuclease (Hha I and Hpa II), and the automated gene sequencing technique were utilized in this study to evaluate the characteristics of endometriotic lesions clone. RESULTS: Of 50 specimens of isolated glands, 34 were informative for clonal analysis, and all of which showed monoclonality. Of 3 ovarian endometriotic tissues, one tissue of HUMARA showed unuseful information, the other 2 ovarian endometriotic tissues respectively had 4 and 7 informative specimens of gland epithelial cells, and all of the glands from each tissue showed uniform clonal pattern. Two peritoneal endometriotic tissues had 1 and 5 informative specimens from individual glands, respectively; and the clonal patterns in 5 glands from the single lesion were divergent. Two abdominal wall endometriotic tissues had 7 and 6 informative specimens, respectively; and variable clonal patterns were seen in different glands from each lesion. One deep infiltrating endometriotic lesion had 4 informative specimens of isolated glands, and all of them showed unique clonal pattern. The disparate clonal patterns were found in endometriotic lesions with variable pathological subtypes, even arising from the same patient. CONCLUSIONS: The epithelial cells from individual endometriotic gland showed monoclonality, and different glands from the same endometriotic lesion might show divergent patterns.