Wheat Seed Detection and Counting Method Based on Improved YOLOv8 Model.

Wheat seed detection has important applications in calculating thousand-grain weight and crop breeding. In order to solve the problems of seed accumulation, adhesion, and occlusion that can lead to low counting accuracy, while ensuring fast detection speed with high accuracy, a wheat seed counting method is proposed to provide technical support for the development of the embedded platform of the seed counter. This study proposes a lightweight real-time wheat seed detection model, YOLOv8-HD, based on YOLOv8. Firstly, we introduce the concept of shared convolutional layers to improve the YOLOv8 detection head, reducing the number of parameters and achieving a lightweight design to improve runtime speed. Secondly, we incorporate the Vision Transformer with a Deformable Attention mechanism into the C2f module of the backbone network to enhance the network's feature extraction capability and improve detection accuracy. The results show that in the stacked scenes with impurities (severe seed adhesion), the YOLOv8-HD model achieves an average detection accuracy (mAP) of 77.6%, which is 9.1% higher than YOLOv8. In all scenes, the YOLOv8-HD model achieves an average detection accuracy (mAP) of 99.3%, which is 16.8% higher than YOLOv8. The memory size of the YOLOv8-HD model is 6.35 MB, approximately 4/5 of YOLOv8. The GFLOPs of YOLOv8-HD decrease by 16%. The inference time of YOLOv8-HD is 2.86 ms (on GPU), which is lower than YOLOv8. Finally, we conducted numerous experiments and the results showed that YOLOv8-HD outperforms other mainstream networks in terms of mAP, speed, and model size. Therefore, our YOLOv8-HD can efficiently detect wheat seeds in various scenarios, providing technical support for the development of seed counting instruments.

Hyaluronic acid-modified mesoporous silica nanoprobes for target identification of atherosclerosis.

Rupture of vulnerable plaque and secondary thrombosis caused by atherosclerosis are one of the main causes of acute cardiovascular and cerebrovascular events, and it is urgent to develop an in-situ, noninvasive, sensitive and targeted detection method at molecular level. We chose CD44, a specific receptor highly expressed on the surface of macrophages, as the target of the molecular probe, and modified the CD44 ligand HA onto the surface of Gd2O3@MSN, constructing the MRI imaging nanoprobe HA-Gd2O3@MSN for targeted recognition of atherosclerosis. The fundamental properties of HA-Gd2O3@MSN were initially investigated. The CCK-8, hemolysis, hematoxylin-eosin staining tests and blood biochemical assays confirmed that HA-Gd2O3@MSN possessed excellent biocompatibility. Laser confocal microscopy, cellular magnetic resonance imaging, flow cytometry and immunohistochemistry were used to verify that the nanoprobes had good targeting properties. The in vivo targeting performance of the nanoprobes was further validated by employing a rabbit atherosclerosis animal model. In summary, the synthesized HA-Gd2O3@MSN nanoprobes have excellent biocompatibility properties as well as good targeting properties. It could provide a new technical tool for early identification of atherosclerosis.

Salt Effect Engineering Single Fe-N2P2-Cl Sites on Interlinked Porous Carbon Nanosheets for Superior Oxygen Reduction Reaction and Zn-Air Batteries.

Developing efficient metal-nitrogen-carbon (M-N-C) single-atom catalysts for oxygen reduction reaction (ORR) is significant for the widespread implementation of Zn-air batteries, while the synergic design of the matrix microstructure and coordination environment of metal centers remains challenges. Herein, a novel salt effect-induced strategy is proposed to engineer N and P coordinated atomically dispersed Fe atoms with extra-axial Cl on interlinked porous carbon nanosheets, achieving a superior single-atom Fe catalyst (denoted as Fe-NP-Cl-C) for ORR and Zn-air batteries. The hierarchical porous nanosheet architecture can provide rapid mass/electron transfer channels and facilitate the exposure of active sites. Experiments and density functional theory (DFT) calculations reveal the distinctive Fe-N2P2-Cl active sites afford significantly reduced energy barriers and promoted reaction kinetics for ORR. Consequently, the Fe-NP-Cl-C catalyst exhibits distinguished ORR performance with a half-wave potential (E1/2) of 0.92 V and excellent stability. Remarkably, the assembled Zn-air battery based on Fe-NP-Cl-C delivers an extremely high peak power density of 260 mW cm-2 and a large specific capacity of 812 mA h g-1, outperforming the commercial Pt/C and most reported congeneric catalysts. This study offers a new perspective on structural optimization and coordination engineering of single-atom catalysts for efficient oxygen electrocatalysis and energy conversion devices.

A Novel pH-Responsive Iron Oxide Core-Shell Magnetic Mesoporous Silica Nanoparticle (M-MSN) System Encapsulating Doxorubicin (DOX) and Glucose Oxidase (Gox) for Pancreatic Cancer Treatment.

Introduction: This study developed a pancreatic cancer targeted drug delivery system that responds to changes in acidity. The system was based on iron oxide core-shell magnetic mesoporous silica nanoparticles (M-MSNs) to treat pancreatic cancer through combined chemotherapy and starvation therapy. Methods: Glucose oxidase (Gox) was coupled to the cancer cell surface to reduce glucose availability for cancer cells, exacerbating the heterogeneity of the tumor microenvironment. Reduced pH accelerated the depolymerization of pH-sensitive polydopamine (PDA), thereby controlling the spatial distribution of Gox and release of doxorubicin (DOX) within tumor cells. Results: Characterization results showed the successful synthesis of DG@M-MSN-PDA-PEG-FA (DG@NPs) with a diameter of 66.02 ± 3.6 nm. In vitro data indicated DG@NPs were highly effective and stable with good cellular uptake shown by confocal laser scanning microscopy (CLSM). DG@NPs exhibited high cytotoxicity and induced apoptosis. Additionally, in vivo experiments confirmed DG@NPs effectively inhibited tumor growth in nude mice with good biosafety. The combination of starvation therapy and chemotherapy facilitated drug release, suggesting DG@NPs as a novel drug delivery system for pancreatic cancer treatment. Conclusion: This study successfully constructed a doxorubicin release system responsive to acidity changes for targeted delivery in pancreatic cancer, providing a new strategy for combination therapy.

cRGD-Conjugated GdIO Nanoclusters for the Theranostics of Pancreatic Cancer through the Combination of T1-T2 Dual-Modal MRI and DTX Delivery.

Clinically, magnetic resonance imaging (MRI) often uses contrast agents (CAs) to improve image contrast, but single-signal MRI CAs are often susceptible to calcification, hemorrhage, and magnetic sensitivity. Herein, iron acetylacetone and gadolinium acetylacetone were used as raw materials to synthesize a T1-T2 dual-mode imaging gadolinium-doped iron oxide (GdIO) nanocluster. Moreover, to endow the nanoclusters with targeting properties and achieve antitumor effects, the cyclic Arg-Gly-Asp (cRGD) peptide and docetaxel (DTX) were attached to the nanocluster surface, and the efficacy of the decorated nanoclusters against pancreatic cancer was evaluated. The final synthesized material cRGD-GdIO-DTX actively targeted αvß3 on the surface of Panc-1 pancreatic cancer cells. Compared with conventional passive targeting, the enrichment of cRGD-GdIO-DTX in tumor tissues improved, and the diagnostic accuracy was significantly enhanced. Moreover, the acidic tumor microenvironment triggered the release of DTX from cRGD-GdIO-DTX, thus achieving tumor treatment. The inhibition of the proliferation of SW1990 and Panc-1 pancreatic cancer cells by cRGD-GdIO-DTX was much stronger than that by the untargeted GdIO-DTX and free DTX in vitro. In addition, in a human pancreatic cancer xenograft model, cRGD-GdIO-DTX considerably slowed tumor development and demonstrated excellent magnetic resonance enhancement. Our results suggest that cRGD-GdIO-DTX has potential applications for the precise diagnosis and efficient treatment of pancreatic cancer.

Functionalized europium-doped hollow mesoporous silica nanospheres as a cell imaging and drug delivery agents.

In an effort to enhance the antitumor efficacy of breast cancer treatment, the chemotherapeutic agent Paclitaxel (PTX) was encapsulated within hyaluronic acid (HA) modified hollow mesoporous silica (HMSNs). In vitro drug release assays showed that the resulting formulation, Eu-HMSNs-HA-PTX, exhibited enzyme-responsive drug release. In addition, cell cytotoxicity and hemolysis assays demonstrated the favorable biocompatibility of both Eu-HMSNs and Eu-HMSNs-HA. Notably, compared to Eu-HMSNs alone, Eu-HMSNs-HA showed enhanced accumulation within CD44-expressing cancer cells (MDA-MB-231). As anticipated, apoptosis experiments indicated that Eu-HMSNs-HA-PTX displayed significantly greater cytotoxicity toward MDA-MB-231 cells than non-targeted Eu-HMSNs-PTX and free PTX. In conclusion, Eu-HMSNs-HA-PTX demonstrated excellent anticancer effects and holds promise as a potent candidate for the efficient therapy of breast cancer.

HClO imaging in vivo and drug-damaged liver tissues by a large Stokes shift fluorescent probe.

Drug-induced liver injury (DILI), as a classic acute inflammation, has attracted widespread concern due to its unpredictability and severity. Among the various reactive oxygen species, HClO has been used as a marker for the detection of DILI process. Thus, we designed and synthesized a "turn-on" fluorescent probe FBC-DS by modifying 3'-formyl-4'-hydroxy-[1,1'-biphenyl]-4-carbonitrile (FBC-OH) with N, N-dimethylthiocarbamate group for sensitively sensing HClO. Probe FBC-DS showed a low detection limit (65 nM), fast response time (30 s), an enormous Stokes shift (183 nm) and 85-fold fluorescence enhancement at 508 nm in the detection of HClO. Probe FBC-DS could monitor exogenous and endogenous HClO in living HeLa cells, HepG2 cells and zebrafish. In addition, probe FBC-DS has been successfully utilized in biological vectors for imaging acetaminophen (APAP)-induced endogenous HClO. Moreover, DILI caused by APAP is evaluated by probe FBC-DS through imaging over-expression of endogenous HClO in the mice liver injury models. All in all, we have every reason to believe that probe FBC-DS can be a potential tool to study the complex biological relationship between HClO and drug-induced liver injury.

Combination of Mn-Mo Oxide Nanoparticles on Carbon Nanotubes through Nitrogen Doping to Catalyze Oxygen Reduction.

An efficient and low-cost oxygen catalyst for the oxygen reduction reaction (ORR) was developed by in situ growth of Mn-Mo oxide nanoparticles on nitrogen-doped carbon nanotubes (NCNTs). Doped nitrogen effectively increases the electron conductivity of the MnMoO4@NCNT complex and the binding energy between the Mn-Mo oxide nanoparticles and carbon nanotubes (CNTs), leading to fast charge transfer and more catalytically active sites. Combining Mn and Mo with NCNTs improves the catalytic activity and promotes both electron and mass transfers, greatly enhancing the catalytic ability for ORR. As a result, MnMoO4@NCNT exhibited a comparable half-wave potential to commercial Pt/C and superior durability, demonstrating great potential for application in renewable energy conversion systems.

Engineered Graphene Quantum Dots as a Magnetic Resonance Signal Amplifier for Biomedical Imaging.

The application of magnetic resonance imaging (MRI) nano-contrast agents (nano-CAs) has increasingly attracted scholarly interest owing to their size, surface chemistry, and stability. Herein, a novel T1 nano-CA (Gd(DTPA)-GQDs) was successfully prepared through the functionalization of graphene quantum dots with poly(ethylene glycol) bis(amine) and their subsequent incorporation into Gd-DTPA. Remarkably, the resultant as-prepared nano-CA displayed an exceptionally high longitudinal proton relaxivity (r1) of 10.90 mM-1 s-1 (R2 = 0.998), which was significantly higher than that of commercial Gd-DTPA (4.18 mM-1 s-1, R2 = 0.996). The cytotoxicity studies indicated that the Gd(DTPA)-GQDs were not cytotoxic by themselves. The results of the hemolysis assay and the in vivo safety evaluation demonstrate the outstanding biocompatibility of Gd(DTPA)-GQDs. The in vivo MRI study provides evidence that Gd(DTPA)-GQDs exhibit exceptional performance as T1-CAs. This research constitutes a viable approach for the development of multiple potential nano-CAs with high-performance MR imaging capabilities.

A heterozygous mutation in ITGB4 causing a mild phenotype of junctional epidermolysis bullosa.

Mutations in ITGB4 are known to cause autosomal recessive junctional epidermolysis bullosa (JEB), which is manifested by severe blistering and granulation tissue, usually complicating pyloric atresia and even leading to death. ITGB4-associated autosomal dominant epidermolysis bullosa has rarely been documented. Herein, we identified a heterozygous pathogenic variant (c.433G>T; p.Asp145Tyr) in ITGB4 causing a mild phenotype of JEB in a Chinese family.

Enterokinase deficiency with novel TMPRSS15 gene mutation masquerading as acrodermatitis enteropathica.

Enterokinase deficiency (EKD) is a rare autosomal recessive inherited disorder caused by loss-of-function mutations of the transmembrane protease serine 15 (TMPRSS15) gene. To date, only 12 cases of EKD have been described in the literature and skin involvement has seldom been described. We identified a novel homozygous nonsense mutation in the TMPRSS15 gene (c.1216C>T, p.R406*) in a female infant, who manifested with acrodermatitis enteropathica (AE)-like lesions that were dramatically relieved within 11 days after initiation of a protein-rich hydrolyzed formula. Our case shows that AE-like rashes can be a manifestation of EKD and expands the spectrum of causative mutations in the TMPRSS15 gene.

pH-Responsive Drug Delivery and Imaging Study of Hybrid Mesoporous Silica Nanoparticles.

A system of pH-responsive and imaging nanocarriers was developed using mesoporous silica nanoparticles (MSNs), in which gadolinium (Gd) was doped through in situ doping (Gd2O3@MSN). Sodium alginate (SA) was attached to the surfaces of the amino groups of MSNs (NH2-Gd2O3@MSN) through the electrostatic adsorption between the amino groups and the carboxyl groups with the formation of hybrid SA-Gd2O3@MSN nanoparticles (NPs). The SA-coated NPs were spherical or near-spherical in shape with an average size of nearly 83.2 ± 8.7 nm. The in vitro drug release experiments of a model rhodamine B (RhB) cargo were performed at different pH values. The result confirmed the pH-responsiveness of the nanocarriers. The results of the cytotoxicity studies indicated that the SA-Gd2O3@MSN NPs were not cytotoxic by themselves. The results of the in vivo safety evaluation and the hemolysis assay confirmed that the system is highly biocompatible. It is noteworthy that the T1 contrast of the system was significantly enhanced by the Gd, as indicated by the result of the MR imaging. This study confirms that the synthesized hybrid nanosystem is promising for pH-responsive drug delivery and MR imaging for cancer diagnosis and treatment.

Anti-melanoma effect and action mechanism of a novel chitosan-based composite hydrogel containing hydroxyapatite nanoparticles.

Hydroxyapatite nanoparticles (HANPs) have been increasingly regarded and reported due to their potential anti-tumor ability. Previously, we found that the rod-like HANPs had good application potential for cutaneous melanoma (CMM). To satisfy the actual requirements in repairing post-operative skin defects and inhibiting CMM recurrence after tumorectomy, we constructed a novel chitosan/alginate (CS/Alg) hydrogel containing the aforementioned HANPs. The in vitro cell experiments confirmed that activated mitochondrial-dependent apoptosis was tightly related to the anti-tumor ability of HANPs. Specifically, we further discovered several target proteins might be involved in abnormal activating Wnt, proteoglycans in cancer, oxidative phosphorylation and p53 signaling pathways. The in vivo animal experiments demonstrated that the HANPs-loaded CS/Alg hydrogel (CS/Alg/HANPs) had a similar effect on inhibiting tumor growth as HANPs, and CS/Alg hydrogel as well as phosphate buffered saline (PBS) group (control) not showed any effect, proving the key role of HANPs. The immunohistochemical staining demonstrated a tumor inhibition via the mitochondria-mediated apoptosis pathway, consistent with the in vitro evaluation. Moreover, CS/Alg/HANPs exhibited no additional biosafety risk to the functions of major organs. Overall, this CS/Alg/HANPs hydrogel has substantial application potential for treating CMM.

Secondary acrodermatitis enteropathica-like skin findings in a case of methylmalonic acidemia.

Methylmalonic acidemia (MMA) is an autosomal recessive genetic disorder caused by decreased activity of methylmalonyl-CoA mutase or metabolic disturbance of its coenzyme cobalamin, cutaneous manifestations are rare clinical signs in this disease. Herein, we describe a Chinese boy with MMA fed with a formula lacking branched-chain amino acids presenting with erythroderma and acrodermatitis enteropathica-like rash, a homozygous nonsense mutation c.742C>T (p.Gln248*) was identified in the MMAA gene. The pedigree exhibited a non-Mendelian inheritance pattern which was attributed to maternal uniparental disomy on chromosome 4q26-q34.1 of the proband, confirmed by chromosomal microarray analysis. Our case highlights the association between skin changes and nutritional deficiency due to therapeutic amino acid restrictions in MMA.

A fast-responsive fluorescent probe based on a styrylcoumarin dye for visualizing hydrogen sulfide in living MCF-7 cells and zebrafish.

As a vital antioxidant molecule, H2S can make an important contribution to regulating blood vessels and inhibiting apoptosis when present at an appropriate concentration. Higher levels of H2S can interfere with the physiological responses of the respiratory system and central nervous system carried out by mammalian cells. This is associated with many illnesses, such as diabetes, mental decline, cardiovascular diseases, and cancer. Therefore, the accurate measurement of H2S in organisms and the environment is of great significance for in-depth studies of the pathogenesis of related diseases. In this contribution, a new coumarin-carbazole-based fluorescent probe, COZ-DNBS, showing a rapid response and large Stokes shift was rationally devised and applied to effectively sense H2S in vivo and in vitro. Upon using the probe COZ-DNBS, the established fluorescent platform could detect H2S with excellent selectivity, showing 62-fold fluorescence enhancement, a fast-response time (<1 min), high sensitivity (38.6 nM), a large Stokes shift (173 nm), and bright-yellow emission. Importantly, the probe COZ-DNBS works well for monitoring levels of H2S in realistic samples, living MCF-7 cells, and zebrafish, showing that COZ-DNBS is a promising signaling tool for H2S detection in biosystems.

Construction of novel coumarin-carbazole-based fluorescent probe for tracking of endogenous and exogenous H2S in vivo with yellow-emission and large Stokes shift.

Recent medical studies have confirmed that endogenous H2S serves as the third gas-messenger besides nitric oxide (NO) and carbon monoxide (CO), which is produced by enzyme-catalyzed metabolism of cysteine and takes part in multiple physiological processes. The abnormal levels induced by H2S overproduction in mammals can destroy tissues and organ systems, which lead to certain serious diseases, such as neurodegenerative diseases, cardiovascular diseases, and various cancers. In this work, we developed a novel coumarin-carbazole fluorescent probe COZ-DNB with yellow emission and a large Stokes shift for H2S detection. In probe COZ-DNB, the newly dye COZ-OH as a luminophore and the 2,4-dinitrophenyl ether moiety was chosen as a trigger group for H2S. Probe COZ-DNB itself displayed nearly non-fluorescent. However, COZ-DNB gave the remarkable fluorescence with an 83-fold enhancement in the yellow region after interaction with H2S. The sensing mechanism of COZ-DNB toward H2S was checked by means of UHPLC, HRMS and DFT/TD-DFT calculations. What's more, probe COZ-DNB also exhibited fast response (2.0 min), high sensitivity (65.0 nM), a large Stokes shift (161.0 nm), high stability and excellent selectivity. Furthermore, COZ-DNB was applied for imaging of exogenous and endogenous H2S in living HeLa cells and zebrafish with satisfactory performances. We anticipate COZ-DNB would be served as a potential tool for investigating the biological functions of H2S in pathological processes.

Sulfone-Decorated Conjugated Organic Polymers Activate Oxygen for Photocatalytic Methane Conversion.

Oxidizing CH4 into liquid products with O2 under mild conditions still mainly relies on metal catalysis. We prepared a series of sulfone-modified conjugated organic polymers and found that the catalyst with proper SVI content (0.10) could drive O2 →H2 O2 →⋅OH to oxidize CH4 into CH3 OH and HCOOH directly and efficiently at room temperature under light irradiation. Experimental results showed that after 4 h reaction, decomposition rate and residual amounts of H2 O2 were 81.21 % and 4.83 mmol gcat -1 respectively, and CH4 conversion rate was 22.81 %. Mechanism studies revealed that illumination could induce the homolytic dissociation of S=O bonds on catalyst to produce oxygen and sulfur radicals, where the ⋅O could adsorb and activate CH4 , and the ⋅S could supply electrons for 1 O2 to generate H2 O2 and then for decomposing the H2 O2 into ⋅OH timely to oxidize CH4 . This research provided a novel organic catalysis approach for oxygen activation and utilization.

Gadolinium-Coated Mesoporous Silica Nanoparticle for Magnetic Resonance Imaging.

Magnetic resonance molecular imaging can provide anatomic, functional and molecular information. However, because of the intrinsically low sensitivity of magnetic resonance imaging (MRI), high-performance MRI contrast agents are required to generate powerful image information for image diagnosis. Herein, we describe a novel T 1 contrast agent with magnetic-imaging properties facilitated by the gadolinium oxide (Gd2O3) doping of mesoporous silica nanoparticles (MSN). The size, morphology, composition, MRI relaxivity (r 1 ), surface area and pore size of these nanoparticles were evaluated following their conjugation with Gd2O3 to produce Gd2O3@MSN. This unique structure led to a significant enhancement in T 1 contrast with longitudinal relaxivity (r 1 ) as high as 51.85 ± 1.38 mM-1s-1. Gd2O3@MSN has a larger T 1 relaxivity than commercial gadolinium diethylene triamine pentaacetate (Gd-DTPA), likely due to the geometrical confinement effect of silica nanoparticles. These results suggest that we could successfully prepare a novel high-performance T 1 contrast agent, which may be a potential candidate for in-vivo MRI.