Background: Theaflavins (TFs) are a category of natural compounds characterized with the benzotropolone skeleton. The prominent benefits of TFs have been well documented. Amount of research were ...conducted and excellent achievements were disclosed during the past years. However, as far as we know, there is no comprehensive review about TFs.
Scope and approach: This review summarized the recent research progress. The activity of TFs on anti-oxidation, anti-mutagenicity, hypolipidemic, anti-inflammatory, anti-cancer, anti-viral effect as well as the epidemiological cure were sorted. Converging pioneer literature and deduction, the underlying formation mechanism of TFs was proposed. Subsequently, acquisition of TFs was pointed out to be the fundament for further research. Accelerated by enzyme, bio-synthesis of TFs were reviewed simultaneously. At the end, employing modern analysis instrument and technology, isolations of TFs were enumerated.
Key findings and conclusions: Structure of the skeleton as well as functional groups were paramount related with the bio-activity of TFs. Meanwhile, oxidation pathway of two catechin molecules to form TFs were hypothesized. Also, ascertainment of the several therapeutic efficiency of the family members of TFs would be the next step in the future.
Nanoparticles are frequently designed to improve the pharmacokinetics profiles and tissue distribution of small molecules to prolong their systemic circulation, target specific tissue, or widen the ...therapeutic window. The multifunctionality of nanoparticles is frequently presented as an advantage but also results in distinct and complicated in vivo disposition properties compared with a conventional formulation of the same molecules. Physiologically based pharmacokinetic (PBPK) modeling has been a useful tool in characterizing and predicting the systemic disposition, target exposure, and efficacy and toxicity of various types of drugs when coupled with pharmacodynamic modeling. Here we review the unique disposition characteristics of nanoparticles, assess how PBPK modeling takes into account the unique disposition properties of nanoparticles, and comment on the applications and challenges of PBPK modeling in characterizing and predicting the disposition and biological effects of nanoparticles.
The accumulation of ice will reduce the performance of the base material and lead to all kinds of damage, even a threat to people's life safety. Recent increasing studies suggest that ...superhydrophobic surfaces (SHSs) originating from nature can remove impacting and condensing droplets from the surface before freezing to subzero temperatures, and it can be seen that hydrophobic/SH coating has good freezing cold resistance. But such anti-icing performances and developments in practical applications are restricted by various factors. In this paper, the mechanism and process of surface icing phenomenon are introduced, as well as how to prevent surface icing on SHS. The development of SH materials in the aspect of anti-icing in recent years is described, and the existing problems in the aspect of anti-icing are analyzed, hoping to provide new research ideas and methods for the research of anti-icing materials.
This paper reviews how to prevent surface icing of superhydrophobic materials from three aspects—removing water droplets before freezing, extending icing time, and reducing ice adhesion—as well as three main techniques to improve the mechanical stability of superhydrophobic materials—doping some flexible polymer substrates, applying a microscale “shell,” and using hydrophobic nanoparticles. Display omitted
Materials science; Biomaterials; Surface science
microRNAs (miRNAs) are a class of negative regulators that take part in many processes such as growth and development, stress responses, and metabolism in plants. Recently, miRNAs were shown to ...function in plant nutrient metabolism. Moreover, several miRNAs were identified in the response to nitrogen (N) deficiency. To investigate the functions of other miRNAs in N deficiency, deep sequencing technology was used to detect the expression of small RNAs under N-sufficient and -deficient conditions. The results showed that members from the same miRNA families displayed differential expression in response to N deficiency. Upon N starvation, the expression of miR169, miR171, miR395, miR397, miR398, miR399, miR408, miR827, and miR857 was repressed, whereas those of miR160, miR780, miR826, miR842, and miR846 were induced. miR826, a newly identified N-starvation-induced miRNA, was found to target the AOP2 gene. Among these N-starvation-responsive miRNAs, several were involved in cross-talk among responses to different nutrient (N, P, S, Cu) deficiencies. miR160, miR167, and miR171 could be responsible for the development of Arabidopsis root systems under N-starvation conditions. In addition, twenty novel miRNAs were identified and nine of them were significantly responsive to N-starvation. This study represents comprehensive expression profiling of N-starvation-responsive miRNAs and advances our understanding of the regulation of N homeostasis mediated by miRNAs.
Glioblastoma is the most common primary brain tumor in adults and still remains incurable, due to the limited accumulation of drugs in the tumor area. Herein, iRGD‐modified nanoparticles, ...DOX@MSN‐SS‐iRGD&1MT, are developed for simultaneous delivery of chemotherapeutic agents (doxorubicin, DOX) and immune checkpoint inhibitor (1‐methyltryptophan, 1MT) into orthotopic glioma. The nanoparticles are comprised of mesoporous silica nanoparticles loaded with DOX, combined with Asp‐Glu‐Val‐Asp (DEVD) connected 1MT, and finally modified by iRGD. These nanoparticles show the capability of penetrating through blood brain barrier into the tumor area, and significantly improve accumulation of drugs in orthotopic brain tumors with minimal side effects. The nanoparticles also activate cytotoxic CD8+ T lymphocytes and inhibit CD4+ T cells in both GL261 cells cocultured with splenocytes in vitro and GL261‐luc orthotopic tumors in vivo. Moreover, the expression of antitumor cytokines IFNα/β, IFN‐γ, TNF, IL‐17, STING, and GrzB is upregulated while protumor proteins p‐STAT3 and IL‐10 are downregulated in the brain tumor area. This study demonstrates the advantages of chemo‐immunotherapeutic nanoparticles accumulated in the brain tumor area and their effectively inhibiting tumor proliferation, which establishes a delivery platform to promote antitumor immunity against glioblastoma.
Anti‐glioblastoma immunotherapy triggered by chemo‐immunotherapeutic nanoparticles:iRGD modified nanoparticles delivers immune checkpoint inhibitor and chemotherapeutic drugs into orthotopic glioma area. With the release of loaded drugs, tumor infiltrating lymphocytes are recruited and activated. The combinational chemo‐immunotherapeutic nanoparticles elicit significant antitumor immunity against glioblastoma.
Tea is a popular beverage over the world for centuries. It is well known that tea has various health benefits such as anti-tumor, antioxidation, antiphlogosis as well as prevention of cardiovascular ...disease, etc. Phytochemicals in tea leaves are the contributors to the excellent bioactivities of tea. Therein, flavonoids were the most potent compounds. Thousands of pioneer work had been made to investigate the potential of tea flavonoids as candidates. This review sorted the literature published in recent 5 years. In view of processing method, basic manufacturing procedures for the traditional types of tea were described. Research progress and functionality of tea flavonoids were discussed according to chemical structures. Fruitful research results about tea flavonoids were summarized and refined, and in-depth cognition of tea flavonoids would be obtained. We also point out the forthcoming orientation for the study on tea flavonoids based on our own understanding and consideration.
Accumulated shrimp shell waste is a source of environmental pollution and represents a waste of resources. Recycling shell waste into valuable fractions using cost-effective and environmentally ...benign approaches remains challenging. To address this issue, in this study a clean and efficient enzymatic process was developed to recover most components of shrimp shell waste including protein, chitin, astaxanthin, and minerals. The process used two recombinant aspartic proteases for protein hydrolysis, recombinant chitinase for chitin hydrolysis, and ethyl acetate for astaxanthin extraction. Deproteinization rendered shell chitin accessible to chitinase, and astaxanthin was easily extracted from shell residue after protein and chitin removal. The process was completed within hours and resulted in high recovery rates of protein (91.4%) and chitin (88.9%). Importantly, amino acids in peptides, the N-acetyl group of chitin oligomers, and astaxanthin in the final products were preserved in their natural states, unlike with traditional chemical or physical treatments. The products have potential applications in nutrition and as anti-inflammatory and antioxidant agents. This enzymatic process promotes sustainable development by establishing a circular economy in shrimp processing, thus offering both economic and environmental benefits.
Display omitted
•An enzyme-based biorefinement process for zero-waste shell utilization was developed.•The process involved protein and chitin hydrolysis and astaxanthin extraction.•The process was rapid and had high protein (91.4%) and chitin (88.9%) yields.•Products retained their native state, unlike with chemical or physical treatments.•The process was cleaner and less costly than traditional method.
Sanguinarine is a bioactive compound as a quaternary benzophenanthridine alkaloid from plant of the Macleaya cordata, Papaveraceae family. The present study was conducted to investigate the effects ...of dietary sanguinarine supplementation on growth performance, serum biochemistry parameters, intestinal mucosal morphology and gut microbiome in yellow feathered broilers. Two hundred and seventy 1-d-old female broilers were randomly assigned to 3 treatments (1) Basal diet (NG); (2) Basal diet containing bacitracin methylene disalicylate (50mg/Kg diet) (ANT); ⢠Basal diet containing sanguinarine (0.7 mg/ kg of feed) (SAG). The statistical results showed that dietary sanguinarine supplementation enhanced growth performance and decreased glucose, uric acid as well as urea nitrogen levels of broilers at 28d of age (P<0.05). The 16S rRNA gene sequence analysis revealed that sanguinarine significantly decreased the species from the phyla Bacteroidetes, and increased the species from phyla Firmicutes. Moreover, dietary sanguinarine supplementation improved mucosal morphology to achieve higher ratio of intestinal villus height to crypt depth (P < 0.05), and decreased the concentrations of TNF-alpha and IL-4 in jejunum mucosal. This study demonstrated that sanguinarine supplementation in the diet of yellow feathered broilers improved intestinal morphology and microbiota community structure to promote growth performance on 1-28d.
•Six full-scale tunnel fire tests were conducted at high altitude of 4100m.•The HRR, temperature distribution and the smoke spread were experimentally studied.•Reduced atmospheric pressure impacts ...the smoke movement significantly.•The Mass Loss Rate at high altitude are lower than the theoretical prediction.•The dimensionless temperature decays slowly at high altitude than that at low altitude in a tunnel fire.
The high-altitude environment, with reduced atmospheric pressure, low air and oxygen density as well as low temperature, significantly affects the characteristics of the tunnel fire. In this paper, six full-scale fire tests were conducted in a road tunnel at high altitude of 4100m. Three oil pools with areas of 0.8m2, 1.0m2 and 2.0m2 were employed as the fire sources. The Heat Release Rate (HRR), longitudinal and vertical temperature distributions, smoke propagation and back-layering were investigated in tests. The experimental results indicate that the Mass Loss Rate (MLR) at high altitude is lower than the theoretical one, and both the HRR growth rates and HRR growth rates per unit area increase with the pool size while the HRR per unit area seem to be independent of the pool size in this study. Additionally, the longitudinal dimensionless temperature with dimensionless distance were compared with the fire test conducted at normal altitude, arguing that the dimensionless temperature decays slowly at high altitude of 4100m than at normal altitude of 773m. The experimental results contribute to intensively understanding on fire characteristics of the tunnel at high altitude and to optimizing the fire detection and the emergency ventilation.
The transition from dormancy to germination in seeds is a key physiological process during the lifecycle of plants. Abscisic acid (ABA) is the sole plant hormone known to maintain seed dormancy; it ...acts through a gene expression network involving the transcription factor ABSCISIC ACID INSENSITIVE 3 (ABI3). However, whether other phytohormone pathways function in the maintenance of seed dormancy in response to environmental and internal signals remains an important question. Here, we show that the plant growth hormone auxin, which acts as a versatile trigger in many developmental processes, also plays a critical role in seed dormancy in Arabidopsis . We show that disruptions in auxin signaling in MIR160- overexpressing plants, auxin receptor mutants, or auxin biosynthesis mutants dramatically release seed dormancy, whereas increases in auxin signaling or biosynthesis greatly enhance seed dormancy. Auxin action in seed dormancy requires the ABA signaling pathway (and vice versa), indicating that the roles of auxin and ABA in seed dormancy are interdependent. Furthermore, we show that auxin acts upstream of the major regulator of seed dormancy, ABI3, by recruiting the auxin response factors AUXIN RESPONSE FACTOR 10 and AUXIN RESPONSE FACTOR 16 to control the expression of ABI3 during seed germination. Our study, thus, uncovers a previously unrecognized regulatory factor of seed dormancy and a coordinating network of auxin and ABA signaling in this important process.
PDF
