Rapid single-particle chemical imaging of nanoplastics by SRS microscopy.

Plastics are now omnipresent in our daily lives. The existence of microplastics (1 µm to 5 mm in length) and possibly even nanoplastics (<1 µm) has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body. However, detecting nanoplastics imposes tremendous analytical challenges on both the nano-level sensitivity and the plastic-identifying specificity, leading to a knowledge gap in this mysterious nanoworld surrounding us. To address these challenges, we developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm that allows micro-nano plastic analysis at the single-particle level with high chemical specificity and throughput. We first validated the sensitivity enhancement of the narrow band of SRS to enable high-speed single nanoplastic detection below 100 nm. We then devised a data-driven spectral matching algorithm to address spectral identification challenges imposed by sensitive narrow-band hyperspectral imaging and achieve robust determination of common plastic polymers. With the established technique, we studied the micro-nano plastics from bottled water as a model system. We successfully detected and identified nanoplastics from major plastic types. Micro-nano plastics concentrations were estimated to be about 2.4 ± 1.3 × 105 particles per liter of bottled water, about 90% of which are nanoplastics. This is orders of magnitude more than the microplastic abundance reported previously in bottled water. High-throughput single-particle counting revealed extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies; the resulting multidimensional profiling sheds light on the science of nanoplastics.

Quantitative Label-Free Chemical Imaging of PLGA Nanoparticles in Cells and Tissues with Single-Particle Sensitivity.

Nanomedicine has brought significant advancements to healthcare by utilizing nanotechnology in medicine. Despite much promise, the further development of nanocarriers for clinical use has been hindered by a lack of understanding and visualization of nano-bio interactions. Conventional imaging methods have limitations in resolution, sensitivity, and specificity. This study introduces a label-free optical approach using stimulated Raman scattering (SRS) microscopy to image poly(lactic-co-glycolic acid) (PLGA) nanocarriers, the most widely used polymeric nanocarrier for delivery therapeutic agents, with single-particle sensitivity and quantification capabilities. A unique Raman peak was identified for PLGA ester, enabling generalized bio-orthogonal bond imaging. We demonstrated quantitative SRS imaging of PLGA nanocarriers across different biological systems from cells to animal tissues. This label-free imaging method provides a powerful tool for studying this prevalent nanocarrier and quantitatively visualizing their distribution, interaction, and clearance in vivo.

Epigenetic-based combination therapy and liposomal codelivery overcomes osimertinib-resistant NSCLC via repolarizing tumor-associated macrophages.

Osimertinib (Osi) is widely used as a first-line treatment for non-small cell lung cancer (NSCLC) with EGFR mutations. However, the majority of patients treated with Osi eventually relapse within a year. The mechanisms of Osi resistance remain largely unexplored, and efficient strategies to reverse the resistance are urgently needed. Here, we developed a lactoferrin-modified liposomal codelivery system for the combination therapy of Osi and panobinostat (Pan), an epigenetic regulator of histone acetylation. We demonstrated that the codelivery liposomes could efficiently repolarize tumor-associated macrophages (TAM) from the M2 to M1 phenotype and reverse the epithelial-mesenchymal transition (EMT)-associated drug resistance in the tumor cells, as well as suppress glycolysis, lactic acid production, and angiogenesis. Our results suggested that the combination therapy of Osi and Pan mediated by liposomal codelivery is a promising strategy for overcoming Osi resistance in NSCLC.

ScRNA-seq links dental fibroblasts heterogeneity with mechanoresponsiveness.

BACKGROUND AND OBJECTIVE: Periodontal ligament (PDL) and dental pulp (DP) share a common origin but have distinct biological and mechanical functions. To what extent the mechanoresponsive property of PDL can be attributed to its unique transcriptional profiles of cellular heterogeneity is unclear. This study aims to decipher cellular heterogeneity and distinct mechanoresponsive characteristics of odontogenic soft tissues and their underlying molecular mechanisms. MATERIALS AND METHODS: A single-cell comparison of digested human periodontal ligament (PDL) and dental pulp (DP) was performed using scRNA-seq. An in vitro loading model was constructed to measure mechanoresponsive ability. Dual-luciferase assay, overexpression, and shRNA knockdown were used to investigate the molecular mechanism. RESULTS: Our results demonstrate striking fibroblast heterogeneity across and within human PDL and DP. We demonstrated that a tissue-specific subset of fibroblasts existed in PDL exhibiting high expression of mechanoresponsive extracellular matrix (ECM) genes, which was verified by an in vitro loading model. ScRNA-seq analysis indicated a particularly enriched regulator in PDL-specific fibroblast subtype, Jun Dimerization Protein 2 (JDP2). Overexpression and knockdown of JDP2 extensively regulated the downstream mechanoresponsive ECM genes in human PDL cells. The force loading model demonstrated that JDP2 responded to tension and that knockdown of JDP2 effectively inhibited the mechanical force-induced ECM remodeling. CONCLUSIONS: Our study constructed the PDL and DP ScRNA-seq atlas to demonstrate PDL and DP fibroblast cellular heterogeneity and identify a PDL-specific mechanoresponsive fibroblast subtype and its underlying mechanism.

Effect of Walking Exercise and Intestinal Cleansing Interval on Bowel Preparation Quality, a Single-Blind, Randomized Controlled Trial.

BACKGROUND AND AIMS: High-quality intestinal preparation could promote intestinal cleanliness and lead to more accurate diagnosis, which patients will benefit from. This study aimed to explore the effectiveness of walking exercise and intestinal cleansing interval in bowel preparation before colonoscopy. METHODS: A randomized controlled single blind study was conducted during August 2021 to February 2022. Patients requiring colonoscopy were randomly divided into three groups: 0 step, 5000 steps or 10,000 steps during the intestinal preparation. Participants took the same intestinal cleansing drugs 4-6 h prior to the procedure: 2L-dose polyethylene glycol (PEG). RESULTS: A total of 300 patients were enrolled in the experiment (100 patients per group), and the baseline information of the three groups was close. The BBPS of right (0-step group vs 5,000-step group vs 10,000-step group: 1.78 ± 0.65 vs 1.88 ± 0.54 vs 2.36 ± 0.69, p < 0.001), transverse (0-step group vs 5,000-step group vs 10,000-step group: 2.09 ± 0.78 vs 2.18 ± 0.61 vs 2.59 ± 0.71, p < 0.001) and left (0-step group vs 5,000-step group vs 10,000-step group: 2.01 ± 0.91 vs 2.24 ± 0.59 vs 2.51 ± 0.60, p < 0.001) colon in 10,000-step group were significantly higher than others, respectively. And we also drew the same conclusion in the aspect of ADR. The adverse events and patients' satisfaction had no differences between the two groups. Moreover, intestinal cleansing interval (< 5.12 h) was only effective in BBPS of right colon (p < 0.001) and left colon (p = 0.039). CONCLUSIONS: This study suggested that participants took 10,000-step walking exercise and took PEG 5.12 h prior to the procedure were effective in routine pre-procedure cleanout for standard colonoscopy. NAME OF REGISTRY: Effect of starting time of bowel cleansing and walking exercise after bowel cleansing on bowel preparation: A prospective randomized controlled study. REGISTRATION NUMBER: ChiCTR2100049214.

[Quality Evaluation of Temporomandibular Joint Images from 3 High-resolution Dynamic Sequences].

Objective To compare the image quality of three high-resolution dynamic MRI methods for evaluating the motion of temporomandibular joint disc and condyle. Methods Twenty-five patients with suspected temporomandibular joint disorders were examined by single-shot fast spin-echo (SSFSE),fast imaging employing steady-state acquisition (FIESTA),and spoiled gradient echo (SPGR) on the oblique sagittal position.Two radiologists performed subjective and objective evaluation on the images with double-blind method.The subjective evaluation included the signal intensity of mandibular condyle,articular disc,soft tissue around articular disc,and lateral pterygoid muscle,the contrast between articular disc and condyle,the contrast between articular disc and surrounding soft tissue,condylar motion,and disc movement.The objective evaluation indexes included image signal intensity,signal-to-noise ratio (SNR),and contrast-to-noise ratio (CNR).The subjective and objective indexes of the image quality were compared between the three sequences. Results The SSFSE sequence had lower signal intensity of articular disc and higher signal intensity of condyle and surrounding soft tissue than FIESTA and SPGR sequences (all P<0.001).The SPGR sequence showed higher signal intensity of lateral pterygoid muscle than the SSFSE and FIESTA sequences (P=0.017,P<0.001).Among the three sequences,SSFSE sequence showed the clearest articular disc structure (χ2=41.952,P<0.001),the strongest contrast between articular disc and condyle (χ2=35.379,P<0.001),the strongest contrast between articular disc and surrounding soft tissue (χ2=27.324,P<0.001),and the clearest movement of articular disc (χ2=44.655,P<0.001).SSFSE and FIESTA sequences showed higher proportion of disc displacement and reduction than SPGR sequence (all P<0.001).The CNR (χ2=21.400,P<0.001),SNR (χ2=34.880,P<0.001),and condyle signal intensity (F=337.151,P<0.001) demonstrated differences among SSFSE,FIESTA,and SPGR sequences.The CNR of SSFSE sequence was higher than that of FIESTA sequence (P<0.001),while it had no significant difference between SSFSE and SPGR sequences (P=0.472).In addition,the SSFSE sequence had higher SNR and signal intensity than FIESTA and SPGR sequences (all P<0.001). Conclusion The best image quality can be observed from SSFSE sequence where both the structure and movement of temporomandibular joint are well displayed.Therefore,SSFSE is preferred for the examination of temporomandibular joint movement.

The subgenomes show asymmetric expression of alleles in hybrid lineages of Megalobrama amblycephala × Culter alburnus.

Hybridization drives rapid speciation by shaping novel genotypic and phenotypic profiles. Genomic incompatibility and transcriptome shock have been observed in hybrids, although this is rarer in animals than in plants. Using the newly sequenced genomes of the blunt snout bream (Megalobrama amblycephala [BSB]) and the topmouth culter (Culter alburnus [TC]), we focused on the sequence variation and gene expression changes in the reciprocal intergeneric hybrid lineages (F1-F3) of BSB × TC. A genome-wide transcriptional analysis identified 145-974 expressed recombinant genes in the successive generations of hybrid fish, suggesting the rapid emergence of allelic variation following hybridization. Some gradual changes of gene expression with additive and dominance effects and various cis and trans regulations were observed from F1 to F3 in the two hybrid lineages. These asymmetric patterns of gene expression represent the alternative strategies for counteracting deleterious effects of the subgenomes and improving adaptability of novel hybrids. Furthermore, we identified positive selection and additive expression patterns in transforming growth factor, beta 1b (tgfb1b), which may account for the morphological variations of the pharyngeal jaw in the two hybrid lineages. Our current findings provide insights into the evolution of vertebrate genomes immediately following hybridization.

Intranasal delivery of plasmids expressing bovine herpesvirus 1 gB/gC/gD proteins by polyethyleneimine magnetic beads activates long-term immune responses in mice.

BACKGROUND: DNA vaccine is one of the research hotspots in veterinary vaccine development. Several advantages, such as cost-effectiveness, ease of design and production, good biocompatibility of plasmid DNA, attractive biosafety, and DNA stability, are found in DNA vaccines. METHODS: In this study, the plasmids expressing bovine herpesvirus 1 (BoHV-1) gB, gC, and gD proteins were mixed at the same mass ratio and adsorbed polyethyleneimine (PEI) magnetic beads with a diameter of 50 nm. Further, the plasmid and PEI magnetic bead polymers were packaged into double carboxyl polyethylene glycol (PEG) 600 to use as a DNA vaccine. The prepared DNA vaccine was employed to vaccinate mice via the intranasal route. The immune responses were evaluated in mice after vaccination. RESULTS: The expression of viral proteins could be largely detected in the lung and rarely in the spleen of mice subjected to a vaccination. The examination of biochemical indicators, anal temperature, and histology indicated that the DNA vaccine was safe in vivo. However, short-time toxicity was observed. The total antibody detected with ELISA in vaccinated mice showed a higher level than PBS, DNA, PEI + DNA, and PBS groups. The antibody level was significantly elevated at the 15th week and started to decrease since the 17th week. The neutralizing antibody titer was significantly higher in DNA vaccine than naked DNA vaccinated animals. The total IgA level was much greater in the DNA vaccine group compared to other component vaccinated groups. The examination of cellular cytokines and the percentage of CD4/CD8 indicated that the prepared DNA vaccine induced a strong cellular immunity. CONCLUSION: The mixed application of plasmids expressing BoHV-1 gB/gC/gD proteins by nano-carrier through intranasal route could effectively activate long-term humoral, cellular, and mucosal immune responses at high levels in mice. These data indicate PEI magnetic beads combining with PEG600 are an efficient vector for plasmid DNA to deliver intranasally as a DNA vaccine candidate.

Ano6 disruption impairs acinar cell regulatory volume decrease and protein secretion in murine submandibular salivary glands.

The widely expressed Anoctamin 6 (Ano6) supports different Ca2+ -dependent functions, but little is known about its role in salivary glands. Mouse submandibular gland (SMG) acinar cells exhibited a robust regulatory volume decrease (RVD) following cell swelling that was reduced approximately 70% in Ano6-/- mice. Ca2+ -free conditions nearly eliminated the RVD response suggesting that Ano6 is an obligatory component of the cell volume-activated, Ca2+ -dependent RVD pathway in salivary gland acinar cells. Ex vivo agonist-stimulated secretion of water and ions was unaffected by Ano6 disruption under both isotonic and hypotonic conditions suggesting that Ano6 does not play a major role in fluid and electrolyte secretion. In contrast, the total amount of ß-adrenergic-dependent protein secretion by the SMG was significantly reduced in Ano6-/- mice. Closer inspection of these latter results revealed that protein secretion was affected only in the female SMG by Ano6 disruption. These results indicate that Ano6 modulates the RVD response and protein secretion by salivary gland acinar cells.

Development and optimization of levodopa and benzylhydrazine orally disintegrating tablets by direct compression and response surface methodology.

The number of Parkinson's disease (PD) patients with the advanced phase and motor fluctuations is increasing. The objective of this study is developing levodopa/benzylhydrazine orally disintegrating tablets (L/B ODTs), which would provide greater convenience and ease of use than conventional tablets for these patients. In the present study, the L/B ODTs were developed successfully with an optimized formulation using response surface methodology (RSM). The direct compression technology was employed for the preparation of L/B ODTs. Considerably shorter disintegration time and faster dissolution profile were obtained under the optimum formulation with microcrystalline cellulose 25.7%, cross-polyvinylpyrrolidone 6.22% and Sodium carboxymethyl starch 5.36%. The content uniformity (%) of levodopa and benzylhydrazine was 50 ± 1.4% and 14.25 ± 0.6%, respectively. Thickness, friability, hardness and wetting time were 2.8 ± 0.05 mm, 0.46 ± 0.21%, 5.42 ± 1.1 kp and 31.2 ± 2.1 s, respectively, and all of data well comply with the General Principles of the Chinese Pharmacopeia. Mannitol of 22% in formulation could bring a pleasant taste: sweet, cool and refreshing. Almost all the volunteers felt that the ODTs had good taste, no roughness, and no gritty feeling, indicating that the ODTs prepared had good palatability, so patients will have good compliance when taking medicine.

The apical anion exchanger Slc26a6 promotes oxalate secretion by murine submandibular gland acinar cells.

The solute carrier family 26 (SLC26) gene family encodes at least 10 different anion exchangers. SLC26 member 6 (SLC26A6 or CFEX/PAT-1) and the cystic fibrosis transmembrane conductance regulator (CFTR) co-localize to the apical membrane of pancreatic duct cells, where they act in concert to drive HCO3- and fluid secretion. In contrast, in the small intestine, SLC26A6 serves as the major pathway for oxalate secretion. However, little is known about the function of Slc26a6 in murine salivary glands. Here, RNA sequencing-based transcriptional profiling and Western blots revealed that Slc26a6 is highly expressed in mouse submandibular and sublingual salivary glands. Slc26a6 localized to the apical membrane of salivary gland acinar cells with no detectable immunostaining in the ducts. CHO-K1 cells transfected with mouse Slc26a6 exchanged Cl- for oxalate and HCO3-, whereas two other anion exchangers known to be expressed in salivary gland acinar cells, Slc4a4 and Slc4a9, mediated little, if any, Cl-/oxalate exchange. Of note, both Cl-/oxalate exchange and Cl-/HCO3- exchange were significantly reduced in acinar cells isolated from the submandibular glands of Slc26a6-/- mice. Oxalate secretion in submandibular saliva also decreased significantly in Slc26a6-/- mice, but HCO3- secretion was unaffected. Taken together, our findings indicate that Slc26a6 is located at the apical membrane of salivary gland acinar cells, where it mediates Cl-/oxalate exchange and plays a critical role in the secretion of oxalate into saliva.

A plastid phylogeny of the fern genus Arachniodes (Dryopteridaceae).

Arachniodes (Dryopteridaceae) is one of the most confusing and controversial fern genera in terms of its circumscription, nomenclature, and taxonomy. Estimates of species number range from 40 to 200. Previous molecular works included only 2-17 accessions representing 2-12 species of Arachniodes and allied genera, leaving most of the Asian species remain unsampled and the infragneric relationships unclear. In this study DNA sequences of seven plastid markers of 343 accessions representing ca. 68 species of Arachniodes (275 accessions), and 64 outgroup accessions from subfam. Dryopteridoideae and subfam. Polybotryoideae were used to infer a phylogeny with maximum likelihood, Bayesian inference, and maximum parsimony approaches. Our major results include: (1) Two species currently assigned in Arachniodes (A. macrostegia and A. ochropteroides are resolved outside of the core Arachniodes making the currently defined Arachniodes polyphyletic, confirming earlier findings; (2) Lithostegia, Leptorumohra, and Phanerophlebiopsis are indeed synonyms of Arachniodes; (3) Leptorumohra is confirmed to be monophyletic, but Phanerophlebiopsis is polyphyletic; (4) The New World species of Arachniodes are confirmed to be not monophyletic with A. denticulata being nested within the Old World species, suggesting that this species is dispersed from the Old World; (5) Arachniodes s.s is resolved into 12 major clades, some of which are further divisable into recognizable subclades and groups, with A. mutica from Japan being resolved as the sister to the rest of the genus; (6) A number of systematic implications of the phylogeny have been suggested; and (7) the genus is estimated to contain ca. 83 species.

The role of Foxq1 in proliferation of human dental pulp stem cell.

This study aimed to investigate the role for Foxq1 in proliferation activity regulation of dental pulp stem cells (DPSCs). Proliferation of DPSC was induced by calcium hydroxide, then expression alteration of Foxq1 was evaluated. Lentivirus was employed to manipulate Foxq1 level in DPSC, and proliferation activities were evaluated. To look into mechanism regulating Foxq1 level after calcium hydroxide stimulation, expressions of various microRNAs were evaluated, then bioinformatics study and dual-luciferase study were carried out to confirm targeting relationship between microRNA and Foxq1. The result of our study indicated that proliferation activities of DPSCs were enhanced after calcium hydroxide stimulation, during which expression of Foxq1 was also up-regulated. Cell viability and progression from G1 to S phase were both improved with overexpression of Foxq1, and microRNAs profiling study and dual-luciferase result suggested miR-320b contributed to the up-regulation of Foxq1 after calcium hydroxide stimulation. These results suggested that miR-320b mediated Foxq1 up-regulation promote proliferation of dental pulp stem cells.

Rational Design of a Polymer with Robust Efficacy for Intracellular Protein and Peptide Delivery.

The efficient delivery of biopharmaceutical drugs such as proteins and peptides into the cytosol of target cells poses substantial challenges owing to their large size and susceptibility to degradation. Current protein delivery vehicles have limitations such as the need for protein modification, insufficient delivery of large-size proteins or small peptides, and loss of protein function after the delivery. Here, we adopted a rational approach to design a polymer with robust efficacy for intracellular protein and peptide delivery. The polymer is composed of a dendrimer scaffold, a hydrophobic membrane-disruptive region, and a multivalent protein binding surface. It allows efficient protein/peptide binding, endocytosis, and endosomal disruption and is capable of efficiently delivering various biomacromolecules including bovine serum albumin, R-phycoerythrin, p53, saporin, ß-galactosidase, and peptides into the cytosol of living cells. Transduction of apoptotic proteins and peptides successfully induces apoptosis in cancer cells, suggesting that the activities of proteins and peptides are maintained during the delivery. This technology represents an efficient and useful tool for intracellular protein and peptide delivery and has broad applicability for basic research and clinical applications.

Enrichment of total steroidal saponins from the extracts of Trillium tschonoskii Maxim by macroporous resin and the simultaneous determination of eight steroidal saponins in the final product by HPLC.

An effective and simple method was established for the separation and enrichment of steroidal saponins from Trillium tschonoskii Maxim. The adsorption and desorption properties of seven macroporous resins were investigated. Among the tested resins, AB-8 resin showed the best adsorption and desorption capacities. The adsorption of steroidal saponins on AB-8 at 25°C was quite consistent with both the Freundlich isotherm model and the pseudo-second-order kinetics model. By optimizing the dynamic adsorption and desorption parameters, the content of steroidal saponins increased from 5.20% in the crude extracts to 51.93% in the final product, with a recovery yield of 86.67%. Furthermore, by scale-up separation, the concentration and recovery of total steroidal saponins were 43.8 and 85.5%, respectively, which suggested that AB-8 resin had great industrial and pharmaceutical potential because of its high efficiency and cost-effectiveness. In addition, a high-performance liquid chromatography method for the simultaneous determination of eight steroidal saponins was established for the first time, which was employed to qualitatively and quantitatively analyze the final product. Based on the methodological validation results, the high-performance liquid chromatography method can be widely applied to the quality control of steroidal saponins from Trillium tschonoskii Maxim due to its excellent accuracy, stability, and repeatability.

Extraction and Identification of Phlorotannins from the Brown Alga, Sargassum fusiforme (Harvey) Setchell.

Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene), which are unique compounds from marine brown algae. In our present study, a procedure for extraction and enrichment of phlorotannins from S. fusiforme with highly antioxidant potentials was established. After comparison of different extraction methods, the optimal extraction conditions were established as follows. The freeze-dried seaweed powder was extracted with 30% ethanol-water solvent with a solid/liquid ratio of 1:5 at temperature of 25 °C for 30 min. After extraction, the phlorotannins were fractioned by different solvents, among which the ethyl acetate fraction exhibited both the highest total phlorotannin content (88.48 ± 0.30 mg PGE/100 mg extract) and the highest antioxidant activities. The extracts obtained from these locations were further purified and characterized using a modified UHPLC-QQQ-MS method. Compounds with 42 different molecular weights were detected and tentatively identified, among which the fuhalol-type phlorotannins were the dominant compounds, followed by phlorethols and fucophlorethols with diverse degree of polymerization. Eckol-type phlorotannins including some newly discovered carmalol derivatives were detected in Sargassum species for the first time. Our study not only described the complex phlorotannins composition in S. fusiforme, but also highlighted the challenges involved in structural elucidation of these compounds.

Repair of urethral defects with polylactid acid fibrous membrane seeded with adipose-derived stem cells in a rabbit model.

AIM: The aim of this study is to evaluate the capacity of polylactid acid (PLA) fibrous membrane seeded with allogeneic rabbit adipose tissue-derived stem cells (ADSCs) to repair urethral defects in a rabbit model. MATERIALS AND METHODS: Rabbit ADSCs were harvested and phenotypically characterized. Twenty-four New Zealand male rabbits with 5-mm urethral mucosal defects were randomly divided into two groups. They underwent urethroplasty either with PLA fibrous membrane seeded with ADSCs (group A) or blank PLA fibrous membrane (group B). At 4 and 6 weeks after urethroplasty, the urethral grafts were collected and analyzed grossly and histologically. The incidence rate of urethrostenosis was measured. RESULTS: The adipose tissue-derived cells in monolayer culture showed a typical morphology of mesenchymal stem cells (MSCs). They were positive for the MSC marker CD44 but negative for lineage markers CD45 and CD105. Six weeks after surgery, the incidence rate of urethrostenosis in group A was significantly lower than that in group B (p < 0.05). In group A, the ADSC-seeded grafts showed a normal urethral architecture with a thickened muscle layer. In contrast, the newly developed urethra in group B demonstrated a fewer number of urothelial layers and scarce or no smooth muscle cells. CONCLUSION: The PLA scaffold seeded with ADSCs is effective in urethral regeneration in a rabbit model. ADSCs may represent a promising source of seed cells for urethral tissue engineering.

Natural and polyanionic heparin polysaccharide functionalized upconversion nanoparticles for highly sensitive and selective ratiometric detection of pesticide.

Pesticide contamination is a global concern, threatening human health and food safety. Herein, we developed heparin (HEP) functionalized upconversion nanoparticles (UCNPs)-based ratiometric nanosensor for the sensitive detection of 2,6-dichloro-4-nitroaniline (DCN) pesticide via inner filter effect. The strategy for HEP functionalization of UCNPs is based on adjusting the surface potentials of UCNPs with polyanionic HEP through the electrostatic interaction. UCNPs (NaYbF4:Gd/Y/Tm@NaYbF4@NaYF4) was designed with core-shell-shell structure and extra sensitizer layer for efficient and strong upconversion luminescence (UCL) in the range of UV to NIR. After incorporation of DCN, the upconverted UV emission of UCNPs-HEP ratiometric nanosensor was considerably quenched with the NIR UCL at 800 nm remaining unchanged as internal standard. The UCNPs-HEP ratiometric nanosensor can achieve outstandingly selective and sensitive detection of DCN at the wide linear range of 5-300 µM with a detection limit of 0.41 µM. The remarkable applicability of the UCNPs-HEP ratiometric nanosensor was verified in apple, cucumber and grapes samples. The developed UCNPs-HEP ratiometric nanosensor with excellent biocompatibility and water dispersion capability, is promising for convenient, selective and sensitive sensing of DCN towards food and aqueous samples.

Micromorphology reformation of regenerated cellulose nanofibers from corn (Zea Mays) stalk pith in urea solution with high-speed shear induced.

Nanocellulose is a kind of renewable natural polymer material with high specific surface area, high crystallinity, and strong mechanical properties. RC nanofibers (RCNFs) have attracted an increasing attention in various applications due to their high aspect ratio and good flexibility. Herein, a novel and facile strategy for RCNFs preparation with high-speed shear induced in urea solution through "bottom-up" approach was proposed in this work. Results indicated that the average diameter and yield of RCNF was approach to 136.67 nm and 53.3 %, respectively. Meanwhile, due to the regular orientation RC chains and arrangement micro-morphology, RCNFs exhibited high crystallinity, strong mechanical properties, stable thermal degradation performance, and excellent UV resistance. In this study, a novel regeneration process with high-speed shear induced was developed to produce RCNFs with excellent properties. This study paved a strategy for future low-energy production of nanofibers and high value-added conversion applications of agricultural waste.

Tick salivary protein Cystatin: structure, anti-inflammation and molecular mechanism.

Ticks are blood-sucking ectoparasites that secrete immunomodulatory substances in saliva to hosts during engorging. Cystatins, a tick salivary protein and natural inhibitor of Cathepsins, are attracting growing interest globally because of the immunosuppressive activities and the feasibility as an antigen for developing anti-tick vaccines. This review outlines the classification and the structure of tick Cystatins, and focuses on the anti-inflammatory effects and molecular mechanisms. Tick Cystatins can be divided into four families based on structures and cystatin 1 and cystatin 2 are the most abundant. They are injected into hosts during blood feeding and effectively mitigate the host inflammatory response. Mechanically, tick Cystatins exert anti-inflammatory properties through the inhibition of TLR-NF-κb, JAK-STAT and p38 MAPK signaling pathways. Further investigations are crucial to confirm the reduction of inflammation in other cell types like neutrophils and mast cells, and fully elucidate the underlying mechanism (like the structural mechanism) to make Cystatin a potential candidate for the development of novel anti-inflammation agents.