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Ultrashort fiber Bragg gratings (FBGs) possess significant potential as weak sensing units for distributed measurements, the exploitation of which, however, have been usually limited by their inherent wide spectra which is undesirable for most traditional wavelength measurements. In this letter, we propose to use shifted optical Gaussian filters to interrogate such wide spectrum gratings. However, instead of acting like Gaussian edge filters as previously done, to take advantage of spectral feature of ultrashort gratings, here they have a role which is more like shifted matched filters. The measurement inherits the important features of a common shifted Gaussian filter interrogation technique, namely its high flexibility, natural insensitivity to intensity variations, promising future for multichannel interrogation, and a potentially wider measuring range relative to common intensity-based approaches. We believe that this simple concept for ultrashort Bragg gratings should offer the strong foundation for their future applications in distributed measurements. Interrogation of a strain-tuned ultrashort grating was accomplished, with a wide sensitivity tuning range from 2.8 to 10.4 dB/nm achieved. [ABSTRACT FROM PUBLISHER]

A pH-responsive free-blockage release system was achieved through controlling the hydrophobic/hydrophilic conversion of mesoporous silica nanopores. This system further presented pulsatile release with changing pH values between 4.0 and 7.0 for several cycles. This free-blockage release system could also release antitumor agents to induce cell death after infecting tumor cells and could have the ability of continuous infection to tumor cells with high drug-delivery efficiency and few side effects. [ABSTRACT FROM AUTHOR]

Azobenzene-containing compounds were covalently attached onto Si(111) surfaces via Si−O linkages using a two-step procedure. The modified Si(111) surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectroscopy measurements. The monolayer surface showed preferably chemical stability. Switchable photoisomerizability of azobenzene molecules on these modified surfaces was observed in response to alternating UV and visible light exposure. The measured conductivity showed distinct difference with trans and cis forms of azobenzene compounds on as-modified Si(111) surfaces. [ABSTRACT FROM AUTHOR]

Microbial fuel cell (MFC) is a novel technique can solve the waste water problem and generate electricity. This study focuses on the anode material by using co-axial electrospinning method to fabricate polylactic acid (PLLA) microtube array membrane (PLLA MTAM). These MTAM not only have high specific area but also enhance the microbial adhesion ability. The addictive, multi-walled carbon nanotubes (MWCNT), increase the conductivity that can improve the efficiency of MFC. Furthermore, the effects of different numbers of electro spun fiber membrane placed in the anode of dual-chamber MFC on electrical performances are analyzed. The scanning electron microscopy (SEM) images show that MTAM have thin walls and contain pores on its surface which is beneficial for fast mass transport. During acclimation, bacteria regularly accumulate on the surface and formed a lamellar structure. However the bacteria in the inner structure tend to group into individual block. The growth of biofilm obviously affected the electrical performance of the cell. In the acclimation process, more electro spun fiber membranes in the anode raise voltage rapidly due to better electron transfer ability. The use of MTAM as the anode in MFC is beneficial for attaching bacteria in shorter acclimation time. The MFC of 11 MTAMs has a maximum power density of 2.94 mW/m2 and a minimum resistance of 833 Ω. Compared to sealing MTAM, hollow MTAM demonstrate better electrical performance. • Co-axial electrospinning method to fabricate polylactic acid (PLLA) microtube array membrane (PLLA MTAM) • Added multi-walled carbon nanotubes (MWCNT) increase the conductivity that can improve the efficiency of MFC. • The use of MTAM as the anode in MFC is beneficial for attaching bacteria in shorter acclimation time. [ABSTRACT FROM AUTHOR]

Highly stable silver nanoparticle-oligonucleotide conjugates were prepared. Based on the mixed DNA-functionalized silver nanoparticles (AgNPs), multiplex DNA detections were demonstrated successfully by SERS. [ABSTRACT FROM AUTHOR]

Due to the high blood glucose and low oxygen environment in diabetes wounds, complex pathological problems arise, such as failure to upregulate healing factors, biological barriers generation, microvascular lesions, and skin neuropathy. Inspired by nature and traditional Chinese paper‐cutting technology, polypeptide deoxyribonucleic acid (DNA) hydrogel microneedles (MNs) (P‐DNA gel MNs) are prepared. The obtained P‐DNA gel MNs possess optimized structure and large deformability, providing excellent clamping, stability, skin penetration, large deformation, tissue adhesion, and antibacterial properties. By incorporating extracellular vesicles (EVs) extracted under hypoxia (H‐EVs‐hypoxia), P‐DNA gel MNs can regulate tissue microenvironment, scavenge free radicals, and reduce inflammation. Notably, P‐DNA gel MNs integration system activates immune regulation and beneficial pathways, promoting neurogenesis and angiogenesis, reducing pathological pain, and achieving high‐quality healing. Overall, P‐DNA gel MNs system presents a fundamental mechanism for clinical transformation in treating diabetes wounds. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries are common neurological disorders, and the available treatment options, such as conservative management and surgical repair, often yield limited results. However, there is growing interest in the potential of using chitosan-based biopolymers as a novel therapeutic approach to treating these injuries. Chitosan-based biopolymers possess unique characteristics, including biocompatibility, biodegradability, and the ability to stimulate cell proliferation, making them highly suitable for repairing nerve defects and promoting nerve regeneration and functional recovery. Furthermore, these biopolymers can be utilized in drug delivery systems to control the release of therapeutic agents and facilitate the growth of nerve cells. This comprehensive review focuses on the latest advancements in utilizing chitosan-based biopolymers for peripheral nerve regeneration. By harnessing the potential of chitosan-based biopolymers, we can pave the way for innovative treatment strategies that significantly improve the outcomes of peripheral nerve injury repair, offering renewed hope and better prospects for patients in need. [ABSTRACT FROM AUTHOR]

Strontium (Sr) belongs to the same group in the periodic table as calcium (Ca). Sr level can serve as an index of rumen Ca absorption capacity; however, the effects of Sr on Ca2+ metabolism are unclear. This study aims to investigate the effect of Sr on Ca2+ metabolism in bovine rumen epithelial cells. The bovine rumen epithelial cells were isolated from the rumen of newborn Holstein male calves (n = 3, 1 day old, 38.0 ± 2.8 kg, fasting). The half maximal inhibitory concentration (IC50) of Sr-treated bovine rumen epithelial cells and cell cycle were used to establish the Sr treatment model. Transcriptomics, proteomics, and network pharmacology were conducted to investigate the core targets of Sr-mediated regulation of Ca2+ metabolism in bovine rumen epithelial cells. The data of transcriptomics and proteomics were analyzed using bioinformatic analysis (Gene Ontology and Kyoto Encyclopedia of genes/protein). Quantitative data were analyzed using one-way ANOVA in GraphPad Prism 8.4.3 and the Shapiro–Wilk test was used for the normality test. Results presented that the IC50 of Sr treatment bovine rumen epithelial cells for 24 h was 43.21 mmol/L, and Sr increased intracellular Ca2+ levels. Multi-omics results demonstrated the differential expression of 770 mRNAs and 2436 proteins after Sr treatment; network pharmacology and reverse transcriptase polymerase chain reaction (RT-PCR) revealed Adenosylhomocysteine hydrolase-like protein 2 (AHCYL2), Semaphoring 3A (SEMA3A), Parathyroid hormone-related protein (PTHLH), Transforming growth factor β2 (TGF-β2), and Cholesterol side-chain cleavage enzyme (CYP11A1) as potential targets for Sr-mediated Ca2+ metabolism regulation. Together these results will improve the current comprehension of the regulatory effect of Sr on Ca2+ metabolism and pave a theoretical basis for Sr application in bovine hypocalcemia. [ABSTRACT FROM AUTHOR]

There are issues and challenges in treating deep burns because of the long recovery time, frequent dressing changes, wound infection, and easy to form scar that influence aesthetics. Besides, some specific tissues are not suitable for large dressing coverage (e.g., face, perineum). Therefore, an ideal deep burn dressing should have good adhesion properties to fit the wound effectively, painless and quick replacement, resistant to infection, accelerate wound healing, reduce scarring and facilitate monitoring and diagnosis. Herein, an anti‐dehydration and rapid‐trigger multifunctional hydrogel dressing is prepared by interface reaction. The Pacrylamide‐Formylboronicacid‐Tannic acid (PAFT) hydrogels are prepared by a simple method on anti‐dehydration elastomeric membrane, which is obtained using tannic acid as a dynamic cross‐linking agent with 3‐formylboronic acid and acrylamideunder UV light. The hydrogel exhibits a strong interfacial adhesion (892 J m−2 ± 65 J m−2), which rapidly (2 min) decreases (to 180 J m−2 ± 20 J m−2) when in the presence of glucose solution. The hydrogel has excellent anti‐dehydration and moisturizing properties, and also exhibits superior antibacterial properties, hemostasis, and biocompatibility. This hydrogel is transparent allowing effective observation of wound transformation and therapeutics. Moreover, PAFT hydrogel accelerates the healing of deep burns and reduces scars. [ABSTRACT FROM AUTHOR]

Herein, a new DNA-assembled framework structure (DAFS) probe coupled with LAMP-DNA signal transducer is developed for rapid and sensitive detection of miRNA let-7a. The DAFS probe was formed via self-assembly of capture strand (P) and ferrocene-labelled DNA strands (P1, P2) and was immobilized via hybridization of P1 and P2 with the DNA strands tethered to electrode surfaces. On the other hand, forward primer (FP) of LAMP was hybridized with assistant strand (AS) attached on Au@Fe 3 O 4 composite nanoparticles. After LAMP reaction started, the duplex FP:AS was separated to expose the AS. Then, with a facile magnetic separation, the exposed AS was collected and further cut by Mn2+, outputting the signal transducer T *. The DAFS probe could disassemble by the T *in the presence of two hairpin DNA probes (H1, H2) and release the P1 and P2 into the solution, causing an electrochemical signal change for realizing sensitive detection of final target let-7a. The electrochemical detection could complete within 50 min with a good linear relationship from 100 aM to 20 pM and a detection limit of 48 aM. Our biosensors performed well in human serum spiked with the let-7a and the let-7a extracts obtained from the human breast cancer cell (MCF-7). [Display omitted] • The LAMP-DNA signal transducer was collected with Au@Fe 3 O 4 NPs for detection, minimizing possible interferences. • The capture strand of the DAFS probe was located at the outmost side, therefore speeding up the response. • This study demonstrates the promising potential of the DAFS probe for rapidly electrochemical detection of nucleic acids. [ABSTRACT FROM AUTHOR]

A grade 3 burn is a nonstatic fatal injury, which can lead to complete damage to the skin structure, accompanied by a series of symptoms such as persistent inflammation, pain, pruritus, ulcer, and peripheral neuropathy. Although the primary clinical burn treatment is skin grafting, it cannot comprehensively solve burn symptoms. Here, a multifunctional DNA hydrogel integrated system is conveniently obtained through dynamic cross‐linking of the DNA unit, polyacrylamide, and l‐ascorbate 2‐phosphate (l‐A2P) formation of dense hydrogen bonds. The DNA hydrogel is doped with borneol for pain and itch relief. The obtained DNA hydrogel provides a hotbed similar to the extracellular matrix structure in vivo for the growth and development of stem cells, which can regulate cell proliferation, maintain cell viability, and achieve perfect release in a suitable environment. Additionally, the pharmacological wound dressing shell features excellent mechanical behavior, tissue adhesion, and antibacterial properties. Beyond that, the multifunctional DNA hydrogel integrated system can promote macrophage transformation, angiogenesis, and neurogenesis. Notably, the system activates the phosphatidylinositol 3′‐kinase (PI3K)‐Akt signaling pathway, which helps to promote tissue regeneration. Therefore, the DNA hydrogel integrated system opens the cascade mode of effective integrated treatment of burn wounds, further driving the in‐depth study of clinical transformation mechanisms in the future. [ABSTRACT FROM AUTHOR]

The fundamental physical features such as the mechanical properties and microstructures of the uterus need to be considered when building in vitro culture platforms to mimic the uterus for embryo implantation and further development but have long been neglected. Here, a uterus‐inspired niche (UN) constructed by grafting collagen gels onto polydimethylsiloxane based on a systematic investigation of a series of parameters (varying concentrations and thicknesses of collagen gel) is established to intrinsically specify and simulate the mechanics and microstructures of the mouse uterus. This brand‐new and unique system is robust in supporting embryo invasion, as evidenced by the special interaction between the embryos and the UN system and successfully promoting E3.5 embryo development into the early organogenesis stage. This platform serves as a powerful tool for developmental biology and tissue engineering. [ABSTRACT FROM AUTHOR]

The efficacy of neurotherapeutic drugs hinges on their ability to traverse the blood-brain barrier and access the brain, which is crucial for treating or alleviating neurodegenerative diseases (NDs). Given the absence of definitive cures for NDs, early diagnosis and intervention become paramount in impeding disease progression. However, conventional therapeutic drugs and existing diagnostic approaches must meet clinical demands. Consequently, there is a pressing need to advance drug delivery systems and early diagnostic methods tailored for NDs. Certain aptamers endowed with specific functionalities find widespread utility in the targeted therapy and diagnosis of NDs. DNA nanoflowers (DNFs), distinctive flower-shaped DNA nanomaterials, are intricately self-assembled through rolling ring amplification (RCA) of circular DNA templates. Notably, imbuing DNFs with diverse functionalities becomes seamlessly achievable by integrating aptamer sequences with specific functions into RCA templates, resulting in a novel nanomaterial, aptamer-bound DNFs (ADNFs) that amalgamates the advantageous features of both components. This article delves into the characteristics and applications of aptamers and DNFs, exploring the potential or application of ADNFs in drug-targeted delivery, direct treatment, early diagnosis, etc. The objective is to offer prospective ideas for the clinical treatment or diagnosis of NDs, thereby contributing to the ongoing efforts in this critical field. • Aptamers are widely used in the treatment and diagnosis of NDs. • Aptamers can be encoded into RCA templates to obtain functionalized ADNFs. • ADNFs have excellent carrier capabilities and can be tuned for NDs. • ADNFs have potential as therapeutic and diagnostic agents for NDs. [ABSTRACT FROM AUTHOR]

The study aimed to develop a novel, transparent and non-toxic coating with antimicrobial, antioxidant, and antifogging properties. The p -coumaric acid-grafted chitosan (CS-PCA) was synthesized via a carbodiimide coupling reaction and then characterized. The CS-PCA coatings were further prepared using the casting method. The CS-PCA coatings obtained exhibited excellent transparency, UV-light barrier ability, and antifogging properties, as confirmed by spectroscopy and antifogging tests. The CS-PCA coatings showed stronger antioxidant capacity and antimicrobial properties against Escherichia coli , Staphylococcus aureus and Botrytis cinerea compared to CS. The multifunctional coatings were further coated on the polyethylene cling film and their effectiveness was confirmed through a strawberry preservation test. The decay of the strawberries was reduced by CS-PCA coated film at room temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

As a non-invasive visualization technique, photoluminescence imaging (PLI) has found its huge value in many biological applications associated with intracellular process monitoring and early and accurate diagnosis of diseases. PLI can also be combined with therapeutics to build imaging-guided theragnostic platforms for achieving early and precise treatment of diseases. Photodynamic therapy (PDT) as a quintessential phototheranostics technology has gained great benefits from the combination with PLI. Recently, aggregation-induced emission (AIE)-active materials have emerged as one of the most promising bioimaging and phototheranostic agents. Most of AIEgens, however, need to be chemically engineered to form versatile nanocomposites with improved their photophysical property, photochemical activity, biocompatibility, etc. In this review, we focus on three categories of AIE-active nanocomposites and highlight their application progresses in the intracellular biological process monitoring and PLI-guided PDT. We hope this review can guide further development of AIE-active nanocomposites and promote their practical applications for monitoring intracellular biological processes and imaging-guided PDT. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Development of tissue-engineered alternatives to nerve autografts remains a serious challenge particularly considering the electroactive properties of native peripheral nerves. In this study, three-dimensional (3D) conductive nerve scaffolds composed of polycaprolactone (PCL) and carbon nanotubes (CNTs) were fabricated using an integration molding method. In vitro, the combination of PCL/CNTs scaffolds with electrical stimulation that mimic the endogenous electric fields could significantly promote Schwann cell proliferation and neurotrophic factor genes expression. In vivo, the effects of PCL/CNTs scaffolds on peripheral nerve regeneration were investigated using a 15-mm rat sciatic nerve defect model. Functional and histological tests indicated that PCL/CNTs scaffolds could effectively promote nerve regeneration and functional recovery. Therefore, PCL/CNTs scaffolds are promising candidates for peripheral nerve restoration. [ABSTRACT FROM AUTHOR]

Microbial infections result in significant postharvest losses of fresh produce. Microbial metabolism and variation in the quality of fruit and vegetables caused by microbial infection are accompanied by significant carbon dioxide (CO 2) production, contributing to a decreased pH value of the headspace microenvironment. Hence, the work aimed to design a CO 2 -responsive label with freshness indication, stimuli-responsive release antimicrobials, and adhesion for postharvest preservation. The multifunctional label (Eug/CPDH) was prepared by incorporating a mixed methyl red/bromothymol blue dye as an indicator and eugenol (Eug) as an antimicrobial agent into a matrix constructed by crosslinking 3-carboxyphenylboronic acid-grafted chitosan and dopamine-grafted hyaluronic acid (CPDH) through acid-sensitive borate bonds. The microbial infection could be indicated to visualize the freshness. Meanwhile, the label showed a CO 2 -responsive release ability, as confirmed by the release experiment. The antimicrobial test showed that the label had excellent inhibition properties against Escherichia coli , Staphylococcus aureus , and Botrytis cinerea. More importantly, the label could be conveniently adhered to the inner surface of the packaging and its effectiveness was verified by strawberry preservation experiments. At room temperature, the strawberry's reduction in hardness, vitamin C, total phenolic content, anthocyanins, and antioxidant capacity was effectively suppressed, and the shelf life was extended to 5 days. Overall, the CO 2 -responsive label provided a new strategy for developing multifunctional freshness preservation materials. [Display omitted] • The multifunctional label integrated postharvest diagnosis and treatment. • The label could monitor microbiological conditions for freshness indication. • CO 2 accumulation caused by microbial infection was used to trigger eugenol release. • The label had self-adhesive property for practical application. • The label exhibited desirable antimicrobial ability and preservation effect. [ABSTRACT FROM AUTHOR]

Smart antimicrobial active packaging, capable of responsive release of antimicrobial agents under environmental stimuli, has garnered widespread attention in recent years. This study developed an intelligent active packaging, Cin@PVA/CS-Cin nanofiber films via electrospinning, that exhibits dual-stimuli responsiveness for the release of cinnamaldehyde (Cin) antimicrobial agent. This packaging can respond by releasing Cin in a high-humidity environment during fruit storage to inhibit microbial proliferation. Additionally, in the event of Botrytis cinerea colonization causing a pH decrease, it can further respond by releasing Cin to prevent more fruits from being colonized. Experimental results proved that the Cin@PVA/CS-Cin nanofiber film exhibits excellent humidity and pH responsive capabilities for Cin release, along with outstanding pH-responsive antibacterial and antifungal activity. The preservation experiment on strawberries has confirmed that the film effectively extends the shelf life of strawberries. The enhanced stability and improved antimicrobial performance of this more intelligent multi-responsive antimicrobial active packaging hold significant importance for its practical application in complex environments. [Display omitted] • Nanofiber-based smart antibacterial packaging extends fruit shelf life. •The packaging dual-responsive releases cinnamaldehyde by humidity and pH. • In case of microbial colonization, pH-responsive prevents further microbial spread. • The nanofiber film presents remarkable properties for fruit preservation. • Simple preparation process holds promise for practical applications. [ABSTRACT FROM AUTHOR]