Biological Stimuli Research Articles

A Flexible Organic Electrochemical Synaptic Transistor With Dopamine-Mediated Plasticity

Artificial synapses relying on electrical and optical stimuli to implement neuromorphic tasks have been intensively developed, but very few of them can directly respond to real biological neurotransmitter stimulus, thus limiting the seamless integration of bio-electronic interfaces. In this letter, we report a flexible organic electrochemical transistor-based synaptic device, which demonstrates not only short-term synaptic behaviors dominated by the kinetics of ions but also long-term synaptic behaviors derived from the redox reaction of dopamine neurotransmitters. More importantly, we systematically studied the dopamine-mediated synaptic plasticity under both flat and bending states, which shows reliable synaptic response and excellent mechanical flexibility. These results reveal that our device providing a promising way for direct biohybrid integration with soft biological tissues.

Bioparameter-directed nanoformulations as MRI CAs enable the specific visualization of hypoxic tumour.

A malignant tumour has hypoxic cells of varying degrees. The more severe the hypoxic degree, the more difficult the prognosis of the tumour and the higher the recurrence rate. Therefore, tumour hypoxia imaging is crucial. Magnetic resonance imaging (MRI) shows its strength in high resolution, depth of penetration and noninvasiveness. However, it needs more excellent contrast agents (CAs) to combat the complex tumour microenvironment (TME) and increased targeting of tumours to enhance clinical safety. Many research studies have focused on developing hypoxia-responsive MRI CAs that take advantage of the unique characteristics of hypoxic tumours. The low oxygen pressure, acidic TME, and up-regulated redox molecule levels found in hypoxic tumours serve as biological stimuli for nanoformulations that can accurately image the hypoxic region. This review highlights the importance of developing bioparameter-directed nanoformulations as MRI CAs for accurate tumour diagnosis. The design strategies and mechanisms of tumour-hypoxia imaging with nanoformulations are exemplified, with a focus on pH-responsiveness, redox-responsiveness, and p(O2)-responsiveness. The promising future of bioparameter-responsive nanoformulations for accurate tumour diagnosis and personalised cancer treatment is discussed.

New bone formation using antibiotic-loaded calcium sulfate beads in bone transports for the treatment of long-bone osteomyelitis.

Bone transport is one of the most frequently used techniques for critical-sized bone defects due to trauma or infection. To fill the defect area and avoid the collapse of soft tissues during transport, some authors have described the use of polymethylmethacrylate or absorbable antibiotic carriers in the form of cylindrical blocks. In this article, we present our experience in the treatment of post-traumatic osteomyelitis of the lower and upper limbs, using a bone transport technique with antibiotic-loaded calcium sulfate in the form of beads. Results With the progressive absorption of calcium sulfate, we observed the formation of a bone-like tissue envelope at the periphery of the defect area. Histological analysis and direct visualization during open revision surgery of the docking site in all patients confirmed the presence of newly formed bone tissue with a high presence of osteoblasts and few osteoclasts; no areas of necrosis or signs of infection were observed. This bone envelope maintained the mechanical protective function of the transport path and docking site, and also provided a biological stimulus to avoid the development of necrotic areas and optimize the consolidation phase. Conclusion Bone transport with calcium sulfate beads improves biological and mechanical support and reduces the number of surgeries required.

Strawberry Biostimulation: From Mechanisms of Action to Plant Growth and Fruit Quality.

The objective of this review is to present a compilation of the application of various biostimulants in strawberry plants. Strawberry cultivation is of great importance worldwide, and, there is currently no review on this topic in the literature. Plant biostimulation consists of using or applying physical, chemical, or biological stimuli that trigger a response-called induction or elicitation-with a positive effect on crop growth, development, and quality. Biostimulation provides tolerance to biotic and abiotic stress, and more absorption and accumulation of nutrients, favoring the metabolism of the plants. The strawberry is a highly appreciated fruit for its high organoleptic and nutraceutical qualities since it is rich in phenolic compounds, vitamins, and minerals, in addition to being a product with high commercial value. This review aims to present an overview of the information on using different biostimulation techniques in strawberries. The information obtained from publications from 2000-2022 is organized according to the biostimulant's physical, chemical, or biological nature. The biochemical or physiological impact on plant productivity, yield, fruit quality, and postharvest life is described for each class of biostimulant. Information gaps are also pointed out, highlighting the topics in which more significant research effort is necessary.

Comparison of pathogenicity and gene expression profiles between adult Schistosoma japonicum isolated from hilly and marshland and lake regions of Anhui Province

To compare the differences in pathogenicity and gene expression profiles between adult Schistosoma japonicum isolated from hilly and marshland and lake regions of Anhui Province, so as to provide the scientific evidence for formulating the precise schistosomiasis control strategy in different endemic foci. C57BL/6 mice were infected with cercariae of S. japonicum isolates from Shitai County (hilly regions) and Susong County (marshland and lake regions) of Anhui Province in 2021, and all mice were sacrificed 44 days post-infection and dissected. The worm burdens, number of S. japonicum eggs deposited in the liver, and the area of egg granulomas in the liver were measured to compare the difference in the pathogenicity between the two isolates. In addition, female and male adult S. japonicum worms were collected and subjected to transcriptome sequencing, and the gene expression profiles were compared between Shitai and Susong isolates of S. japonicum. The differentially expressed genes (DEGs) were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The total worm burdens [(14.50 ± 3.96) worms/mouse vs. (16.10 ± 3.78) worms/mouse; t = 0.877, P = 0.392], number of female and male paired worms [(4.50 ± 0.67) worms/mouse vs. (5.10 ± 1.45) worms/mouse; t = 1.129, P = 0.280], number of unpaired male worms [(5.50 ± 4.01) worms/mouse vs. (5.60 ± 1.69) worms/mouse; t = 0.069, P = 0.946], number of eggs deposited in per gram liver [(12 116.70 ± 6 508.83) eggs vs. (16 696.70 ± 4 571.56) eggs; t = 1.821, P = 0.085], and area of a single egg granuloma in the liver [(74 359.40 ± 11 766.34) µm2 vs. (74 836.90 ± 13 086.12) µm2; t = 0.081, P = 0.936] were comparable between Shitai and Susong isolates of S. japonicum. Transcriptome sequencing identified 584 DEGs between adult female worms and 1 598 DEGs between adult male worms of Shitai and Susong isolates of S. japonicum. GO enrichment analysis showed that the DEGs between female adults were predominantly enriched in biological processes of stimulus response, cytotoxicity, multiple cell biological processes, metabolic processes, cellular processes and signaling pathways, cellular components of cell, organelles and cell membranes and molecular functions of binding and catalytic ability, and KEGG enrichment analysis showed that these DEGs were significantly enriched in pathways of vascular endothelial growth factor signaling, glutathione metabolism, arginine and proline metabolism. In addition, the DEGs between male adults were predominantly enriched in biological processes of signaling transduction, multiple cell biological processes, regulation of biological processes, metabolic processes, development processes and stimulus responses, cellular components of extracellular matrix and cell junction and molecular functions of binding and catalytic ability, and these DEGs were significantly enriched in pathways of Wnt signaling, Ras signaling, natural killer cells-mediated cytotoxicity, extracellular matrix-receptor interactions and arginine biosynthesis. There is no significant difference in the pathogenicity between S. japonicum isolates from hilly and marshland and lake regions of Anhui Province; however, the gene expression profiles vary significantly between S. japonicum isolates.

Research Status of Microbial-Induced Calcium Carbonate Precipitation Technology Applied to Self-healing Concrete

Microbial-induced calcium carbonate precipitation (MICP) is often used to improve the engineering properties of different building materials in recent years, which has great development prospects. This process takes advantage of the metabolic activity of microorganisms and eventually leads to the precipitation of calcium carbonate through changes in the microbial environment. The self-healing effect (SH effect) of microbial concrete can be explained as the ability to repair cracks in concrete by spontaneously generating biological stimuli by microorganisms to obtain CO32- and react with Ca2+ in the material to form CaCO3 crystals without any external or human intervention. This sustainable development project has replaced traditional techniques for the restoration of concrete.

Relationships of Matrix Metalloproteinase 1 and a Tissue Inhibitor of Metalloproteinase to Collagen Metabolism in Haliotis discus hannai.

In response to physical, chemical, and/or biological stimuli, considerable tissue self-degradation occurs in abalone, causing severe post-harvest quality loss. During this process, the extracellular matrix (ECM) is greatly degraded by endogenous proteases. The main component of the ECM is collagen, primarily type I collagen. Although the activity of matrix metalloproteinases (MMPs), which can specifically degrade collagen, is precisely regulated by tissue inhibitors of MPs (TIMPs), indicating that MMPs and TIMPs play crucial roles in the regulation of tissue self-degradation, few studies have reported the interaction between MMPs and TIMPs. In this study, we reveal collagenases to participate in postmortem tissue self-degradation of Haliotis discus hannai by degrading type I collagen. The recombinant MMP-1 catalytic domain (rMMP1c) of abalone with high purity and enzyme activity is expressed using a prokaryotic expression system. The optimum temperature and pH for rMMP1c are 37 °C and 7.0, respectively. The thermal denaturation temperature of rMMP1c is 67.0 ± 0.9 °C. Ethylenediamine tetraacetic acid (EDTA) and 1,10-phenanthroline can completely inhibit rMMP1c activity, while Ba2+, Ca2+, and Mg2+ can significantly elevate it. TIMP is also expressed using HEK 293F cells. Recombinant TIMP (rTIMP) shows good inhibitory activity toward rMMP1c. Inhibition kinetics analyses reveal rTIMP to be a competitive inhibitor of rMMP1c. Biolayer interferometry reveals that rTIMP can effectively bind with rMMP1c, with an equilibrium dissociation constant value of 263 nM. rMMP1c effectively degrades type I collagen γ-β-α chains in turn, and rTIMP can significantly inhibit rMMP1c degradation activity. These results provide a theoretical basis for the study of MMP and TIMP interaction and elucidate the possible mechanism for abalone tissue self-degradation.

Biomechanical Forces Determine Fibroid Stem Cell Transformation and the Receptivity Status of the Endometrium: A Critical Appraisal.

Myometrium cells are an important reproductive niche in which cyclic mechanical forces of a pico-newton range are produced continuously at millisecond and second intervals. Overproduction and/or underproduction of micro-forces, due to point or epigenetic mutation, aberrant methylation, and abnormal response to hypoxia, may lead to the transformation of fibroid stem cells into fibroid-initiating stem cells. Fibroids are tumors with a high modulus of stiffness disturbing the critical homeostasis of the myometrium and they may cause unfavorable and strong mechanical forces. Micro-mechanical forces and soluble-chemical signals play a critical role in transcriptional and translational processes' maintenance, by regulating communication between the cell nucleus and its organelles. Signals coming from the external environment can stimulate cells in the format of both soluble biochemical signals and mechanical ones. The shape of the cell and the plasma membrane have a significant character in sensing electro-chemical signals, through specialized receptors and generating responses, accordingly. In order for mechanical signals to be perceived by the cell, they must be converted into biological stimuli, through a process called mechanotransduction. Transmission of fibroid-derived mechanical signals to the endometrium and their effects on receptivity modulators are mediated through a pathway known as solid-state signaling. It is not sufficiently clear which type of receptors and mechanical signals impair endometrial receptivity. However, it is known that biomechanical signals reaching the endometrium affect epithelial sodium channels, lysophosphatidic acid receptors or Rho GTPases, leading to conformational changes in endometrial proteins. Translational changes in receptivity modulators may disrupt the selectivity and receptivity functions of the endometrium, resulting in failed implantation or early pregnancy loss. By hypermethylation of the receptivity genes, micro-forces can also negatively affect decidualization and implantation. The purpose of this narrative review is to summarize the state of the art of the biomechanical forces which can determine fibroid stem cell transformation and, thus, affect the receptivity status of the endometrium with regard to fertilization and pregnancy.

Bioactive Porous Particles as Biological and Physical Stimuli for Bone Regeneration.

Even though bony defects can be recovered to their original condition with full functionality, critical-sized bone injuries continue to be a challenge in clinical fields due to deficiencies in the scaffolding matrix and growth factors at the injury region. In this study, we prepared bone morphogenetic protein-2 (BMP-2)-loaded porous particles as a bioactive bone graft for accelerated bone regeneration. The porous particles with unique leaf-stacked morphology (LSS particles) were fabricated by a simple cooling procedure of hot polycaprolactone (PCL) solution. The unique leaf-stacked structure in the LSS particles provided a large surface area and complex release path for the sufficient immobilization of BMP-2 and sustained release of BMP-2 for 26 days. The LSS was also recognized as a topographical cue for cell adhesion and differentiation. In in vitro cell culture and in vivo animal study using a canine mandible defect model, BMP-2-immobilized LSS particles provided a favorable environment for osteogenic differentiation of stem cells and bone regeneration. In vitro study suggests a dual stimulus of bone mineral-like (leaf-stacked) structure (a physical cue) and continuously supplied BMP-2 (a biological cue) to be the cause of this improved healing outcome. Thus, LSS particles containing BMP-2 can be a promising bioactive grafting material for effective new bone formation.

Atypical development of social and nonsocial working memory capacity among preschoolers with autism spectrum disorders.

Individuals with autism spectrum disorders (ASD) have shown impaired performance in canonical and nonsocial working memory (WM). However, no study has investigated social WM and its early development. Using biological motion stimuli, our study assessed the development of social and nonsocial WM capacity among children with or without ASD across the age span between 4 and 6 (N=150). While typically developing (TD) children show a rapid development from age 5 to 6, children with ASD showed a delayed development for both social and nonsocial WM capacity, reaching a significant group difference at age 6. Furthermore, we found a negative correlation between social (but not nonsocial) WM capacity and the severity of autistic symptoms among children with ASD. In contrast, there is a positive correlation between both types of WM capacity and intelligence among TD children but not among children with ASD. Our findings thus indicate that individuals with ASD miss the rapid development of WM capacity in early childhood and, particularly, their delayed social WM development might contribute to core symptoms that critically depend on social information processing.

Comprehensive Identification and Functional Analysis of Stress-Associated Protein (SAP) Genes in Osmotic Stress in Maize.

Stress-associated proteins (SAPs) are a kind of zinc finger protein with an A20/AN1 domain and contribute to plants' adaption to various abiotic and biological stimuli. However, little is known about the SAP genes in maize (Zea mays L.). In the present study, the SAP genes were identified from the maize genome. Subsequently, the protein properties, gene structure and duplication, chromosomal location, and cis-acting elements were analyzed by bioinformatic methods. Finally, their expression profiles under osmotic stresses, including drought and salinity, as well as ABA, and overexpression in Saccharomyces cerevisiae W303a cells, were performed to uncover the potential function. The results showed that a total of 10 SAP genes were identified and named ZmSAP1 to ZmSAP10 in maize, which was unevenly distributed on six of the ten maize chromosomes. The ZmSAP1, ZmSAP4, ZmSAP5, ZmSAP6, ZmSAP7, ZmSAP8 and ZmSAP10 had an A20 domain at N terminus and AN1 domain at C terminus, respectively. Only ZmSAP2 possessed a single AN1 domain at the N terminus. ZmSAP3 and ZmSAP9 both contained two AN1 domains without an A20 domain. Most ZmSAP genes lost introns and had abundant stress- and hormone-responsive cis-elements in their promoter region. The results of quantitative real-time PCR showed that all ZmSAP genes were regulated by drought and saline stresses, as well as ABA induction. Moreover, heterologous expression of ZmSAP2 and ZmSAP7 significantly improved the saline tolerance of yeast cells. The study provides insights into further underlying the function of ZmSAPs in regulating stress response in maize.

"Descriptive Risk-Averse Bayesian Decision-Making," a Model for Complex Biological Motion Perception in the Human Dorsal Pathway.

Biological motion perception is integral not only to survival but also to the social life of human beings. Identifying the underlying mechanisms and their associated neurobiological substrates has been a matter of investigation and debate for some time. Although, in general, it is believed that the integration of local motion and dynamic form cues in the brain empowers the visual system to perceive/recognize biological motion stimuli, some recent studies have indicated the importance of dynamic form cues in such a process. Inspired by the previous neurophysiologically plausible biological motion perception models, a new descriptive risk-averse Bayesian simulation model, capable of discerning a ball's direction from a set of complex biological motion soccer kick stimuli, is proposed. The model represents only the dorsal pathway as a motion information processing section of the visual system according to the two-stream theory. The stimuli used have been obtained from a previous psychophysical study on athletes in our lab. Furthermore, the acquired psychophysical data from that study have been used to re-enact human behavior using our simulation model. By adjusting the model parameters, the psychometric function of athlete subjects has been mimicked. A correlation analysis between human and simulation data shows a significant and robust correlation between angular thresholds and slopes of the psychometric functions of both groups. Although it is established that the visual system optimally integrates all available information in the decision-making process, the results conform to the speculations favoring motion cue importance over dynamic form by testing the limits in which biological motion perception only depends on motion information processing.

The Peach (Prunus persica) CBL and CIPK Family Genes: Protein Interaction Profiling and Expression Analysis in Response to Various Abiotic Stresses.

The plant calcineurin B-like protein-CBL interacting protein kinase (CBL-CIPK) signaling pathway is a Ca2+-related signaling pathway that responds strongly to both biological and abiotic environmental stimuli. This study identified eight CBL and eighteen CIPK genes from peach for the first time. Their basic properties and gene structure were analyzed, and the CBL and CIPK members from Arabidopsis and apple were combined to study their evolutionary relationships. Using RT-qPCR and RNA-seq data, we detected the expression patterns of PprCBLs and PprCIPKs in different tissues and fruit development stages of peach. Among them, the expression levels of PprCBL1 and PprCIPK18 were stable in various tissues and stages. The expression patterns of other members showed specificity between cultivars and developmental stages. By treating shoots with drought and salt stress simulated using PEG6000 and NaCl, it was found that PprCIPK3, PprCIPK6, PprCIPK15 and PprCIPK16 were strongly responsive to salt stress, and PprCIPK3, PprCIPK4, PprCIPK10, PprCIPK14, PprCIPK15, PprCIPK16 and PprCIPK18 were sensitive to drought stress. Three genes, PprCIPK3, PprCIPK15 and PprCIPK16, were sensitive to both salt and drought stress. We cloned four PprCBL and several PprCIPK genes and detected their interaction by yeast two-hybrid assay (Y2H). The results of Y2H show not only the evolutionary conservation of the interaction network of CBL-CIPK but also the specificity among different species. In conclusion, CBL and CIPK genes are important in peach and play an important role in the response to various abiotic stresses.

Biological motion elicits between-person Inhibition of Return in temporal and spatial movement parameters

The present study was designed to gain a deeper understanding of the processing of biological motion stimuli. To this end, we investigated if the inhibition of return (IoR) effect emerges in initiation times and trajectories of pointing movements to targets in left and right space where the preceding cues were pointing movement of a human model or a dot with the same biological motion. Targets were randomly presented in the same or opposite side from the direction of the motion cue. It was hypothesised that the visuomotor system should resonate with the biological motion of a dot, but that the human model should exaggerate the effect. Thus, the human model should trigger stronger attention shifts compared with the dot model and lead to more robust IoR effects in both spatial (movement) and temporal parameters of the observer's pointing responses. Initiation times and the spatial parameters (angle of the hand trajectory) of the pointing movements were analysed. Results indicate that facilitation and IoR effects triggered by human and dot stimuli did not differ. Based on these findings, it seems that the crucial feature of motion cues that generate shifts in attention is biological motion, rather than human appearance per se.

Design and application of stimuli-responsive DNA hydrogels: A review.

Deoxyribonucleic acid (DNA) hydrogels combine the properties of DNAs and hydrogels, and adding functionalized DNAs is key to the wide application of DNA hydrogels. In stimuli-responsive DNA hydrogels, the DNA transcends its application in genetics and bridges the gap between different fields. Specifically, the DNA acts as both an information carrier and a bridge in constructing DNA hydrogels. The programmability and biocompatibility of DNA hydrogel make it change macroscopically in response to a variety of stimuli. In order to meet the needs of different scenarios, DNA hydrogels were also designed into microcapsules, beads, membranes, microneedle patches, and other forms. In this study, the stimuli were classified into single biological and non-biological stimuli and composite stimuli. Stimuli-responsive DNA hydrogels from the past five years were summarized, including but not limited to their design and application, in particular logic gate pathways and signal amplification mechanisms. Stimuli-responsive DNA hydrogels have been applied to fields such as sensing, nanorobots, information carriers, controlled drug release, and disease treatment. Different potential applications and the developmental pro-spects of stimuli-responsive DNA hydrogels were discussed.

The immune system as a system of relations.

Progress in neuroimmunology established that the nervous and the immune systems are two functionally related physiological systems. Unique sensory and immune receptors enable them to control interactions of the organism with the inner and the outer worlds. Both systems undergo an experience-driven selection process during their ontogeny. They share the same mediators/neurotransmitters and use synapses for intercellular communication. They keep a memory of previous experiences. Immune cells can affect nervous cells, nervous cells can affect immune cells, and they regulate each other. I however argue that the two systems differ by three major points: 1) Unlike the nervous system, the immune system has a loose anatomical structure, in which molecular and cellular events mostly occur at random; 2) The immune system can respond to molecules of the living world whereas the nervous system can respond to phenomena of the physical world; 3) Responses of the immune system act both on the organism and on the stimulus that triggered the response, whereas responses of the nervous system act on the organism only. The nervous and the immune systems therefore appear as two complementary systems of relations that closely work together, and whose reactivities are well-suited to deal with physical and biological stimuli, respectively. Its ability both to adapt the organism to the living world and to adapt the living world to the organism endows the immune system with powerful adaptive properties that enable the organism to live in peace with itself and with other living beings, whether pathogens or commensals.

Stress can lead to an increase in smartphone use in the context of texting while walking.

Texting while walking (TWW) is a dangerous behavior that can lead to injury and even death. While several studies have examined the relationship between smartphone use and stress, to our knowledge no studies have yet investigated the relationship between stress and TWW. The objective of the present study was to investigate this relationship by examining the effects of stress on TWW, the effects of TWW on subsequent stress, and the effect of stress on multitasking performance. A total of 80 participants completed two sequential tasks in a laboratory while they walked on a treadmill and responded to a biological motion stimulus imitating the movement of another pedestrian. In the unrestricted task, participants were given the choice to use their personal phones. In the controlled task, they carried a text conversation with a research assistant while they walked and responded to the stimulus. Stress was measured via questionnaire and saliva collection for measure of cortisol (a stress hormone) before and after each task. Results show that greater psychological stress and cortisol variations were associated with a greater number of phone uses during the unrestricted task. Greater phone use during the unrestricted task was associated with lower subsequent psychological stress in women and total time of phone use was correlated with subsequent cortisol levels. Stress measured before the controlled task had no effect on multitasking performance, but participants with moderate performance were those with the highest cortisol levels. Our results suggest that stress could be a precursor to TWW and that it could affect a pedestrian’s ability to stay safe when using their smartphone.

Physiological levels of fluid shear stress modulate vascular function through TRPV4 sparklets.

Endothelial calcium (Ca 2+) signaling plays a major role in regulating vasodilation in response to fluid shear stress (FSS) generated by blood flow. Local Ca 2+ influx through single transient receptor potential channel subfamily V member 4 (TRPV4) (termed "sparklets") activated by low concentrations of chemical and biological stimuli has been revealed to modulate vascular function. However, the range in which FSS can initiate TRPV4 sparklets to induce vasodilation is unknown. Here, we assess the activity of TPRV4 sparklets induced by various physiological levels of FSS and investigate the mechanisms involving these Ca 2+ signals in FSS-induced vasodilation. Intact small mesenteric arteries are used for Ca 2+ imaging with a GCaMP2(TRPV4-KO) mouse model and high-speed confocal systems. Markedly increased local Ca 2+ signals are observed in the endothelium under 4-8 dyne/cm 2 FSS, whereas FSS >8 dyne/cm 2 causes global Ca 2+ influx. Further analysis shows that TRPV4 channels form a four-channel group to mediate Ca 2+ sparklets under certain levels of FSS. The large Ca 2+ influx hyperpolarizes endothelial cells by stimulating intermediate (IK)- and small (SK)-conductance Ca 2+-sensitive potassium channels, leading to hyperpolarization of the surrounding smooth muscle cells and ultimately causing endothelium-dependent vasodilation. In conclusion, Ca 2+ influx transits through a small number of endothelial TRPV4 channels opened by certain levels of FSS, which activates the Ca 2+-sensitive IK and SK channels to cause vasodilation.

Pectin functionalized metal-organic frameworks as dual-stimuli-responsive carriers to improve the pesticide targeting and reduce environmental risks

Encapsulation of active ingredients into intelligent response controlled release carriers has been recognized as a promising approach to enhance the utilization efficiency and reduce the environmental risks of pesticides. In this work, an intelligent redox and pectinase dual stimuli-responsive pesticide delivery system was constructed by bonding pectin with metal-organic frameworks (FeMOF nanoparticles) which were loaded with pyraclostrobin (PYR@FeMOF-pectin nanoparticles). The successful fabrication of PYR@FeMOF-pectin nanoparticles was proved by a series of physicochemical characterizations. The results indicated that the loading capacity of PYR@FeMOF-pectin nanoparticles for pyraclostrobin was approximately 20.6%. The pectin covered on the surface of PYR@FeMOF nanoparticles could protect pyraclostrobin from photolysis and improve their spreadability on rice blades effectively. Different biological stimuli associated with Magnaporthe oryzae could trigger the release of pyraclostrobin from the pesticide-loaded core-shell nanoparticles, resulting in the death of pathogens. The bioactivity survey determined that PYR@FeMOF-pectin nanoparticles had a superior fungicidal activity and a longer duration against Magnaporthe oryzae than pyraclostrobin suspension concentrate. In addition, the FeMOF-pectin nanocarriers showed no obvious phytotoxicity and could enhance the shoot length and root length of rice plants. More importantly, PYR@FeMOF-pectin nanoparticles had an 8-fold reduction in acute toxicity to zebrafish than that of pyraclostrobin suspension concentrate. Therefore, the dual-responsive FeMOF-pectin nanocarriers have great potential for realizing site-specific pesticide delivery and promoting plant growth.

An Overview of the Supramolecular Systems for Gene and Drug Delivery in Tissue Regeneration.

Tissue regeneration is a prominent area of research, developing biomaterials aimed to be tunable, mechanistic scaffolds that mimic the physiological environment of the tissue. These biomaterials are projected to effectively possess similar chemical and biological properties, while at the same time are required to be safely and quickly degradable in the body once the desired restoration is achieved. Supramolecular systems composed of reversible, non-covalently connected, self-assembly units that respond to biological stimuli and signal cells have efficiently been developed as preferred biomaterials. Their biocompatibility and the ability to engineer the functionality have led to promising results in regenerative therapy. This review was intended to illuminate those who wish to envisage the niche translational research in regenerative therapy by summarizing the various explored types, chemistry, mechanisms, stimuli receptivity, and other advancements of supramolecular systems.