Virtual brightfield and fluorescence staining for Fourier ptychography via unsupervised deep learning.

Fourier ptychographic microscopy (FPM) is a computational approach geared towards creating high-resolution and large field-of-view images without mechanical scanning. Acquiring color images of histology slides often requires sequential acquisitions with red, green, and blue illuminations. The color reconstructions often suffer from coherent artifacts that are not presented in regular incoherent microscopy images. As a result, it remains a challenge to employ FPM for digital pathology applications, where resolution and color accuracy are of critical importance. Here we report a deep learning approach for performing unsupervised image-to-image translation of FPM reconstructions. A cycle-consistent adversarial network with multiscale structure similarity loss is trained to perform virtual brightfield and fluorescence staining of the recovered FPM images. In the training stage, we feed the network with two sets of unpaired images: (1) monochromatic FPM recovery and (2) color or fluorescence images captured using a regular microscope. In the inference stage, the network takes the FPM input and outputs a virtually stained image with reduced coherent artifacts and improved image quality. We test the approach on various samples with different staining protocols. High-quality color and fluorescence reconstructions validate its effectiveness.

Super-resolved multispectral lensless microscopy via angle-tilted, wavelength-multiplexed ptychographic modulation.

We report an angle-tilted, wavelength-multiplexed ptychographic modulation approach for multispectral lensless on-chip microscopy. In this approach, we illuminate the specimen with lights at five wavelengths simultaneously. A prism is added at the illumination path for spectral dispersion. Thus, lightwaves at different wavelengths hit the specimen at slightly different incident angles, breaking the ambiguities in mixed-state ptychographic reconstruction. At the detection path, we place a thin diffuser between the specimen and the monochromatic image sensor for encoding the spectral information into 2D intensity measurements. By scanning the sample to different x-y positions, we acquire a sequence of monochromatic images for reconstructing the five complex object profiles at the five wavelengths. An up-sampling procedure is integrated into the recovery process to bypass the resolution limit imposed by the imager pixel size. We demonstrate a half-pitch resolution of 0.55 µm using an image sensor with 1.85 µm pixel size. We also demonstrate quantitative and high-quality multispectral reconstructions of stained tissue sections for digital pathology applications.

Design, synthesis and antifungal activity evaluation of isocryptolepine derivatives.

In this paper, the nitrogen atom was inserted into the anthracycline system of the isocryptolepine nucleus to obtain the "Aza"-type structure benzo[4,5]imidazo[1,2-c] quinazoline. A series of "Aza"-type derivatives were designed, synthesized and evaluated for their antifungal activity against six plant fungi in vitro. Among all derivatives, compounds A-0, B-1 and B-2 showed significant antifungal activity against B. cinerea with the EC50 values of 2.72 µg/mL, 5.90 µg/mL and 4.00 µg/mL, respectively. Compound A-2 had the highest activity against M. oryzae with the EC50 values of 8.81 µg/mL, and compound A-1 demonstrated the most control efficacy against R. solani (EC50, 6.27 µg/mL). Moreover, compound A-0 was selected to investigate the in vivo tests against B. cinerea and the results indicated that the preventative efficacy of it up to 72.80% at 100 µg/mL. Preliminary mechanism studies revealed that after treatment with A-0 at 5 µg/mL, the B. cinerea mycelia appeared curved, collapsed and the cell membrane integrity may be damaged. The reactive oxygen species production, mitochondrial membrane potential and nuclear morphometry of mycelia have been changed, and the membrane function and cell proliferation of mycelia were destroyed. Compounds A-0, A-1, B-1 and B-2 presented weaker toxicities against two cells lines than isocryptolepine. This study lays the foundation for the future development of isocryptolepine derivatives as environmentally friendly and safe agricultural fungicides.

Construction of tissue-engineered lymphatic vessel using human adipose derived stem cells differentiated lymphatic endothelial like cells and decellularized arterial scaffold: A preliminary study.

We have previously demonstrated that human adipose-derived stem cells (hADSCs) can be differentiated into lymphatic endothelial like cells. The purpose of this study was to investigate the feasibility of utilizing the induced lymphatic endothelial like cells and decellularized arterial scaffold to construct the tissue-engineered lymphatic vessel. The hADSCs were isolated from adipose tissue in healthy adults and were characterized the multilineage differentiation potential. Decellularized arterial scaffold was prepared using the Triton x-100 method. ADSCs were differentiated into lymphatic-like endothelial cells, and the induced cells were then seeded onto the decellularized arterial scaffold to engineer the lymphatic vessel. The histological analyses were performed to examine the endothelialized construct. The decellularized arterial scaffold was successfully obtained and was able to maintain its vessel morphology. The isolated ADSCs can be differentiated into osteocytes and adipocytes. After seeding onto the scaffold, the seeded cells attached and grew well on the decellularized arterial scaffold. Our preliminary results demonstrated that the induced lymphatic endothelial like cells combined with decellularized arterial scaffold could be utilized to successfully engineer the lymphatic vessel. Our findings may be helpful for the development of tissue-engineering of the lymphatic graft.

Facile Three-Component Synthesis, Insecticidal and Antifungal Evaluation of Novel Dihydropyridine Derivatives.

In an attempt to find the neonicotinoid insecticides, twenty novel dihydropyridine derivatives were designed, "green" synthesized via one pot facile three-component reaction and evaluated for their bioactivities against Tetranychus cinnabarinus, Myzus persicae, Brevicoryne brassicae, Fusarium oxysporum f. sp. vasinfectum, Magnaporthe oryzae, Sclerotinia sclerotiorum and Botrytis cinereal. All of the tested compounds showed potent insecticidal activity, and some were much better in comparison with imidacloprid (IMI). Especially, compounds 3d (LC50: 0.011 mM) and 5c (LC50: 0.025 mM) were 12.2- and 5.4-fold more active than IMI (LC50: 0.135 mM) against T. cinnabarinus, respectively. Moreover, out of all the derivatives, compound 3d (LC50: 0.0015 mM) exhibited the strongest insecticidal activity against B. brassicae and compound 3i (LC50: 0.0007 mM) displayed the strongest insecticidal activity against M. persicae. Surprisingly, when the concentration of compound 4 was 50 mg/L, the inhibition rate against F. oxysporum and S. sclerotiorum reached 45.00% and 65.83%, respectively. The present work indicated that novel dihydropyridine derivatives could be used as potential lead compounds for developing neonicotinoid insecticides and agricultural fungicides.

Microanatomy of the Separable Length of the C7.

OBJECTIVE: The objective of this study was to provide anatomical data on modified contralateral C7 (cC7) nerve root transfers by dissecting and measuring the separable lengths of the C7 root, trunk, and divisions. MATERIALS AND METHODS: Fifteen adult cervicothoracic specimens were dissected and measured using Vernier calipers after exposing the brachial plexus. Measurements included the length of the C7 from the root to the trunk, the lengths of the C7 root-trunk-anterior division (and posterior division). The epineuria at the C7 root-division-cord junctions were opened until the internal nerve bundles fused together and could not be separated by microdissection. The lengths of the C7 root-trunk-anterior (and posterior) division were measured again after microdissection. The lengths of cC7 nerve of 20 patients with bracial plexus avulsion were measured using the former technique. RESULTS: The length of the C7 root-trunk was 45.87 SD 10.43 mm. Before separation, the lengths of the C7 root-trunk-anterior division and the root-trunk-posterior division were 61.14 SD 13.44 and 54.63 SD 11.35 mm, respectively; after separation, the lengths were 74.67 SD 12.86 and 68.73 SD 11.86 mm, respectively. The prolonged lengths were 13.15 SD 4.26 and 14.21 SD 6.98 mm, respectively. The prolonged lengths were significantly greater (p < 0.05). The prolonged length of C7 nerve clinically was anterior division, 15.30 SD 3.76 mm and posterior division, 11.10 SD 3.01 mm. CONCLUSION: The C7 division lengths can be prolonged by dissecting the epineuria at the division-cord junction of the C7 nerve root.

Ginkgo biloba extract (EGb 761) promotes peripheral nerve regeneration and neovascularization after acellular nerve allografts in a rat model.

This study aimed to investigate whether or not ginkgo biloba extract (EGb 761) enhances peripheral nerve regeneration and vascularization after repair using acellular nerve allografts (ANA). Seventy-two Sprague-Dawley rats were randomly divided into three experimental groups: a unilateral 15-mm sciatic nerve defect was created and repaired with an autologous graft (autograft group); the same defect was repaired with an 18 mm ANA with an i.p. injection of normal saline for 10 days (saline group); and in the final group, the same defect was repaired with an 18 mm ANA with an i.p. injection of EGb 761 for 10 days (EGb 761 group). Axon outgrowth and vascularization were evaluated by immunocytochemistry 14 days post-implantation. The expression of genes associated with angiogenesis was analyzed by real-time polymerase chain reaction (PCR) seven days post-implantation. Compared with the saline group, rats in the EGb 761 group significantly increased the number of myelinated fibers and the average diameter of the nerves within the graft. There is no significant difference between the EGb 761 group and the autograft group. The expression of CD34 and NF200 was significantly higher in the EGb 761 group than in the saline group. Additionally, EGb 761 treatment increased the expression of several angiogenesis-related genes, including Vegf, SOX18, Prom 1, and IL-6. In conclusion, ANA repair with EGb 761 treatment demonstrates effects on peripheral nerve regeneration and vascularization that are equal to those of autologous graft repair, and that are superior to ANA repair alone.

Modified classification and repair of perineal soft tissue injuries associated with open pelvic fractures.

BACKGROUND: This study describes a modified classification and management protocol for perineal soft tissue injuries associated with pelvic fractures. METHODS: A total of 11 patients with perineal soft tissue injuries associated with open pelvic fractures were studied retrospectively. The patients were classified into three types based on the area of defect: type A (urogenital zone), type B (anal zone), and type C (both urogenital and anal zones). Each type included the following subclasses: A1 (without urethra injuries), A2 (with urethra injuries), B1 (without anorectal injuries), B2 (with anorectal injuries), C1 (with types A1 and B1), C2 (with types A2 and B1), C3 (with types A1 and B2), and C4 (with types A2 and B2). The management protocol was planned according to the individual classifications. Protocol A1 (for type A1) involved skin graft or myocutaneous flap transplantation. Protocol A2 (for type A2) involved the same protocol combined with urine diversion. Protocol B1 (for type B1) involved skin graft or myocutaneous flap transplantation. Protocol B2 (for type B2) involved the same management combined with fecal diversion. Protocol C involved the correspondent protocol used for each subtype of type C. RESULTS: Out of the 11 patients, there were 5, 3, and 3 cases of types A, B, and C, respectively. One patient died due to sepsis, and the wounds of the remaining patients healed well. No anal incontinence had occurred. CONCLUSIONS: Perineal soft tissue injuries associated with pelvic fractures can be classified into three types, and the management protocol can be planned according to the classification.

Etifoxine provides benefits in nerve repair with acellular nerve grafts.

INTRODUCTION: Acellular nerve grafts are good candidates for nerve repair, but the clinical outcome of grafting is not always satisfactory. We investigated whether etifoxine could enhance nerve regeneration. METHODS: Seventy-two Sprague-Dawley rats were divided into 3 groups: (1) autograft; (2) acellular nerve graft; and (3) acellular nerve graft plus etifoxine. Histological and electrophysiological examinations were performed to evaluate the efficacy of nerve regeneration. Walking-track analysis was used to examine functional recovery. Quantitative polymerase chain reaction was used to evaluate changes in mRNA level. RESULTS: Etifoxine: (i) increased expression of neurofilaments in regenerated axons; (ii) improved sciatic nerve regeneration measured by histological examination; (iii) increased nerve conduction velocity; (iv) improved walking behavior as measured by footprint analysis; and (v) boosted expression of neurotrophins. CONCLUSIONS: These results show that etifoxine can enhance peripheral nerve regeneration across large nerve gaps repaired by acellular nerve grafts by increasing expression of neurotrophins.

Modified pathological classification of brachial plexus root injury and its MR imaging characteristics.

The authors described a modified pathological classification (PC) of brachial plexus injury (BPI) and its magnetic resonance (MR) imaging characteristics. The reliability and diagnostic accuracy of MR imaging for detecting nerve injury was discussed. Between 2006 and 2010, 86 patients with BPI were managed surgically in our department. Their preoperative MR images and surgical findings were analyzed retrospectively. The PC of BPI was classified into five types: (I) nerve root injury in continuity (including Sunderland grade I-IV injury); (II) postganglionic spinal nerve rupture with or without proximal stump; (III) preganglionic root injury (visible); (IV) preganglionic nerve root injury and postganglionic spinal nerves injury; (V) preganglionic root injury (invisible). The main MR imaging characteristics of BPI included traumatic meningocele, displacement of spinal cord, the absence of nerve root, "Black line" sign, nerve root/trunk injury in continuity, and thickening and edema of nerve root. The accuracy of MR imaging for detecting C5, C6, C7, C8, and T1 nerve roots injury were 93.3, 95.2, 92.3, 84, and 74.4%, respectively. The modified PC provides a detailed description of nerve root injury in BPI, and MR imaging technique is a reliable method for detecting nerve root injury.

Application and Mechanism of Cryptolepine and Neocryptolepine Derivatives as T3SS Inhibitors for Control of Bacterial Leaf Blight on Rice.

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv oryzae (Xoo) is extremely harmful to rice production. The traditional control approach is to use bactericides that target key bacterial growth factors, but the selection pressure on the pathogen makes resistant strains the dominant bacterial strains, leading to a decline in bactericidal efficacy. Type III secretion system (T3SS) is a conserved and critical virulence factor in most Gram-negative bacteria, and its expression or absence does not affect bacterial growth, rendering it an ideal target for creating drugs against Gram-negative pathogens. In this work, we synthesized a range of derivatives from cryptolepine and neocryptolepine. We found that compound Z-8 could inhibit the expression of Xoo T3SS-related genes without affecting the growth of bacteria. an in vivo bioassay showed that compound Z-8 could effectively reduce the hypersensitive response (HR) induced by Xoo in tobacco and reduce the pathogenicity of Xoo in rice. Furthermore, it exhibited synergy in control of bacterial leaf blight when combined with the quorum quenching bacterial F20.

B2C-AFM: Bi-Directional Co-Temporal and Cross-Spatial Attention Fusion Model for Human Action Recognition.

Human Action Recognition plays a driving engine of many human-computer interaction applications. Most current researches focus on improving the model generalization by integrating multiple homogeneous modalities, including RGB images, human poses, and optical flows. Furthermore, contextual interactions and out-of-context sign languages have been validated to depend on scene category and human per se. Those attempts to integrate appearance features and human poses have shown positive results. However, with human poses' spatial errors and temporal ambiguities, existing methods are subject to poor scalability, limited robustness, and sub-optimal models. In this paper, inspired by the assumption that different modalities may maintain temporal consistency and spatial complementarity, we present a novel Bi-directional Co-temporal and Cross-spatial Attention Fusion Model (B2C-AFM). Our model is characterized by the asynchronous fusion strategy of multi-modal features along temporal and spatial dimensions. Besides, the novel explicit motion-oriented pose representations called Limb Flow Fields (Lff) are explored to alleviate the temporal ambiguity regarding human poses. Experiments on publicly available datasets validate our contributions. Abundant ablation studies experimentally show that B2C-AFM achieves robust performance across seen and unseen human actions. The codes are available at https://github.com/gftww/B2C.git.

Ptychographic sensor for large-scale lensless microbial monitoring with high spatiotemporal resolution.

Traditional microbial detection methods often rely on the overall property of microbial cultures and cannot resolve individual growth event at high spatiotemporal resolution. As a result, they require bacteria to grow to confluence and then interpret the results. Here, we demonstrate the application of an integrated ptychographic sensor for lensless cytometric analysis of microbial cultures over a large scale and with high spatiotemporal resolution. The reported device can be placed within a regular incubator or used as a standalone incubating unit for long-term microbial monitoring. For longitudinal study where massive data are acquired at sequential time points, we report a new temporal-similarity constraint to increase the temporal resolution of ptychographic reconstruction by 7-fold. With this strategy, the reported device achieves a centimeter-scale field of view, a half-pitch spatial resolution of 488 nm, and a temporal resolution of 15-s intervals. For the first time, we report the direct observation of bacterial growth in a 15-s interval by tracking the phase wraps of the recovered images, with high phase sensitivity like that in interferometric measurements. We also characterize cell growth via longitudinal dry mass measurement and perform rapid bacterial detection at low concentrations. For drug-screening application, we demonstrate proof-of-concept antibiotic susceptibility testing and perform single-cell analysis of antibiotic-induced filamentation. The combination of high phase sensitivity, high spatiotemporal resolution, and large field of view is unique among existing microscopy techniques. As a quantitative and miniaturized platform, it can improve studies with microorganisms and other biospecimens at resource-limited settings.

Integrated Proteomics and Transcriptomics Analyses Reveals the Possible Antifungal Mechanism of an Indoloquinoline Alkaloid Neocryptolepine against Rhizoctonia solani.

Rhizoctonia solani causes serious plant diseases. Neocryptolepine presented the significant antifungal activity against R. solani, however the mode of action is unclear. In this paper, we investigated the potential mode of action of neocryptolepine against R. solani integrated the proteomics and transcriptomics. Results showed that after treatment with neocryptolepine, 1012 differentially expressed proteins and 10 920 differentially expressed genes of R. solani were found, most of them were enriched in mitochondrial respiratory chain. It affected oxidative phosphorylation led to the enrichment of ROS and the decrease of MMP, and inhibited complex III activity with the inhibition rate of 63.51% at 10 µg/mL. The mitochondrial structural and function were damaged. Cytochrome b-c1 complex subunit Rieske (UQCRFS1) with the high binding score to neocryptolepine was found as a potential target. In addition, it inhibited the sclerotia formation and presented antifungal efficacy by decreasing the diameter of a wound in potato in a concentration-dependent manner. Above results indicated that neocryptolepine inhibited the complex III activity by binding UQCRFS1 and blocked the ion transfer to cause the death of R. solani mycelia. This study laid the foundation for the future development of neocryptolepine as an alternative biofungicide.

Autofocusing technologies for whole slide imaging and automated microscopy.

Whole slide imaging (WSI) has moved digital pathology closer to diagnostic practice in recent years. Due to the inherent tissue topography variability, accurate autofocusing remains a critical challenge for WSI and automated microscopy systems. The traditional focus map surveying method is limited in its ability to acquire a high degree of focus points while still maintaining high throughput. Real-time approaches decouple image acquisition from focusing, thus allowing for rapid scanning while maintaining continuous accurate focus. This work reviews the traditional focus map approach and discusses the choice of focus measure for focal plane determination. It also discusses various real-time autofocusing approaches including reflective-based triangulation, confocal pinhole detection, low-coherence interferometry, tilted sensor approach, independent dual sensor scanning, beam splitter array, phase detection, dual-LED illumination and deep-learning approaches. The technical concepts, merits and limitations of these methods are explained and compared to those of a traditional WSI system. This review may provide new insights for the development of high-throughput automated microscopy imaging systems that can be made broadly available and utilizable without loss of capacity.

Wide-field, high-resolution lensless on-chip microscopy via near-field blind ptychographic modulation.

We report a novel lensless on-chip microscopy platform based on near-field blind ptychographic modulation. In this platform, we place a thin diffuser in between the object and the image sensor for light wave modulation. By blindly scanning the unknown diffuser to different x-y positions, we acquire a sequence of modulated intensity images for quantitative object recovery. Different from previous ptychographic implementations, we employ a unit magnification configuration with a Fresnel number of ∼50 000, which is orders of magnitude higher than those of previous ptychographic setups. The unit magnification configuration allows us to have the entire sensor area, 6.4 mm by 4.6 mm, as the imaging field of view. The ultra-high Fresnel number enables us to directly recover the positional shift of the diffuser in the phase retrieval process, addressing the positioning accuracy issue plaguing regular ptychographic experiments. In our implementation, we use a low-cost, DIY scanning stage to perform blind diffuser modulation. Precise mechanical scanning that is critical in conventional ptychography experiments is no longer needed in our setup. We further employ an up-sampling phase retrieval scheme to bypass the resolution limit set by the imager pixel size and demonstrate a half-pitch resolution of 0.78 µm. We validate the imaging performance via in vitro cell cultures, transparent and stained tissue sections, and a thick biological sample. We show that the recovered quantitative phase map can be used to perform effective cell segmentation of a dense yeast culture. We also demonstrate 3D digital refocusing of the thick biological sample based on the recovered wavefront. The reported platform provides a cost-effective and turnkey solution for large field-of-view, high-resolution, and quantitative on-chip microscopy. It is adaptable for a wide range of point-of-care-, global-health-, and telemedicine-related applications.

Design, Synthesis, and Antifungal Evaluation of 8-Hydroxyquinoline Metal Complexes against Phytopathogenic Fungi.

Phytopathogenic fungal infections have become a major threat to agricultural production, food security, and human health globally, and novel antifungal agents with simple chemical scaffolds and high efficiency are needed. In this study, we designed and synthesized 38 8-hydroxyquinoline metal complexes and evaluated their antifungal activities. The results showed that most of the tested compounds possessed remarkable in vitro antifungal activity. Especially, compound 1e exhibited the highest antifungal potency among all target compounds, with EC50 values of 0.0940, 0.125, 2.95, and 5.96 µg/mL, respectively, against Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium graminearum, and Magnaporthe oryzae. Preliminary mechanistic studies had shown that compound 1e might cause mycelial abnormalities of S. sclerotiorum, cell membrane permeability changes, leakage of cell contents, and inhibition of sclerotia formation and germination. Moreover, the results of in vivo antifungal activity of compound 1e against S. sclerotiorum showed that 1e possessed higher curative effects than that of the positive control azoxystrobin. Therefore, compound 1e is expected to be a novel leading structure for the development of new antifungal agents.

Design, Synthesis, and Antifungal Evaluation of Neocryptolepine Derivatives against Phytopathogenic Fungi.

Neocryptolepine is an alkaloid isolated from traditional African herbal medicine Cryptolepis sanguinolenta, and its broad spectrum of biological activities has been illuminated in past decades. In this study, neocryptolepine and its derivatives (1-49) were designed and synthesized from economical and readily available starting materials. Their structures were confirmed by proton nuclear magnetic resonance, carbon nuclear magnetic resonance, and mass spectrometry. The synthesized compounds were screened for their antifungal profile against six agriculturally important fungi Rhizoctonia solani, Botrytis cinerea (B. cinerea), Fusarium graminearum, Mycosphaerella melonis, Sclerotinia sclerotiorum, and Magnaporthe oryzae. The results of in vitro assay revealed that compounds 5, 21, 24, 35, 40, 45, and 47 presented remarkable antifungal activity against the fungi tested with EC50 values lower than 1 µg/mL. Significantly, compound 24 displayed the most effective inhibitory potency against B. cinerea (EC50 = 0.07 µg/mL), and the data from in vivo experiments revealed that compound 24 demonstrated comparable protective activity with the positive control boscalid. Preliminary mechanism studies indicated that compound 24 showed impressive spore germination inhibitory effectiveness and lower cytotoxicity than azoxystrobin, imparted on normal function of the cell membrane and cell wall, and arrested the normal function of the nucleus. Besides the excellent inhibitory activity against agriculturally important phytopathogenic fungi tested, the designed assemblage possesses several benefits with a high profile of variation in synthesized molecules, the ease of synthesis, and good cost-effectiveness of commercially available synthetic reagents, all of these have highlighted the potential worth of compound 24 as a new and highly efficient agricultural fungicide.

Design, Synthesis, and Antifungal Evaluation of Novel Quinoline Derivatives Inspired from Natural Quinine Alkaloids.

Inspired by quinine and its analogues, we designed, synthesized, and evaluated two series of quinoline small molecular compounds (a and 2a) and six series of quinoline derivatives (3a-f) for their antifungal activities. The results showed that compounds 3e and 3f series exhibited significant fungicidal activities. Significantly, compounds 3f-4 (EC50 = 0.41 µg/mL) and 3f-28 (EC50 = 0.55 µg/mL) displayed the superior in vitro fungicidal activity and the potent in vivo curative effect against Sclerotinia sclerotiorum. Preliminary mechanism studies showed that compounds 3f-4 and 3f-28 could cause changes in the cell membrane permeability, accumulation of reactive oxygen species, loss of mitochondrial membrane potential, and effective inhibition of germination and formation of S. sclerotiorum sclerotia. These results indicate that compounds 3f-4 and 3f-28 are novel potential fungicidal candidates against S. sclerotiorum derived from natural products.

Synthesis and anti-phytopathogenic activity of 8-hydroxyquinoline derivatives.

Phytopathogenic fungi have become a serious threat to the quality of agricultural products, food security and human health globally, necessitating the need to discover new antifungal agents with de novo chemical scaffolds and high efficiency. A series of 8-hydroxyquinoline derivatives were designed and synthesized, and their antifungal activity was evaluated against five phytopathogenic fungi. In vitro assays revealed that most of the tested compounds remarkably impacted the five target fungi and their inhibitory activities were better than that of the positive control azoxystrobin. Compound 2, in particular, exhibited the highest potency among all the tested compounds, with an EC50 of 0.0021, 0.0016, 0.0124, 0.0059 and 0.0120 mM respectively against B. cinerea, S. sclerotiorum, F. graminearum, F. oxysporum and M. oryzae, followed by compound 5c. The morphological observations of optical microscopy and scanning electron microscopy revealed that compounds 2 and 5c caused mycelial abnormalities of S. sclerotiorum. Futhermore, the results of in vivo antifungal activity of compounds 2 and 5c against S. sclerotiorum showed that 5c possessed stronger protective and curative activity than that of 2, and the curative effects of 5c at 40 and 80 µg mL-1 (84.18% and 95.44%) were better than those of azoxystrobin (77.32% and 83.59%). Therefore, compounds 2 and 5c are expected to be novel lead structures for the development of new fungicides.