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Expansion microscopy (ExM) is in increasingly widespread use throughout biology because its isotropic physical magnification enables nanoimaging on conventional microscopes. To date, ExM methods either expand specimens to a limited range (~4-10× linearly) or achieve larger expansion factors through iterating the expansion process a second time (~15-20× linearly). Here, we present an ExM protocol that achieves ~20× expansion (yielding <20-nm resolution on a conventional microscope) in a single expansion step, achieving the performance of iterative expansion with the simplicity of a single-shot protocol. This protocol, which we call 20ExM, supports postexpansion staining for brain tissue, which can facilitate biomolecular labeling. 20ExM may find utility in many areas of biological investigation requiring high-resolution imaging.
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Encéfalo , Animais , Encéfalo/diagnóstico por imagem , Camundongos , Microscopia/métodos , Microscopia/instrumentação , Microscopia de Fluorescência/métodos , Processamento de Imagem Assistida por Computador/métodosRESUMO
Predicting interactions between microbes and hosts plays critical roles in microbiome population genetics and microbial ecology and evolution. How to systematically characterize the sophisticated mechanisms and signal interplay between microbes and hosts is a significant challenge for global health risks. Identifying microbe-host interactions (MHIs) can not only provide helpful insights into their fundamental regulatory mechanisms, but also facilitate the development of targeted therapies for microbial infections. In recent years, computational methods have become an appealing alternative due to the high risk and cost of wet-lab experiments. Therefore, in this study, we utilized rich microbial metagenomic information to construct a novel heterogeneous microbial network (HMN)-based model named KGVHI to predict candidate microbes for target hosts. Specifically, KGVHI first built a HMN by integrating human proteins, viruses and pathogenic bacteria with their biological attributes. Then KGVHI adopted a knowledge graph embedding strategy to capture the global topological structure information of the whole network. A natural language processing algorithm is used to extract the local biological attribute information from the nodes in HMN. Finally, we combined the local and global information and fed it into a blended deep neural network (DNN) for training and prediction. Compared to state-of-the-art methods, the comprehensive experimental results show that our model can obtain excellent results on the corresponding three MHI datasets. Furthermore, we also conducted two pathogenic bacteria case studies to further indicate that KGVHI has excellent predictive capabilities for potential MHI pairs.
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Aprendizado Profundo , Humanos , Reconhecimento Automatizado de Padrão , Redes Neurais de Computação , Algoritmos , BactériasRESUMO
Identifying the potential bacteriophages (phage) candidate to treat bacterial infections plays an essential role in the research of human pathogens. Computational approaches are recognized as a valid way to predict bacteria and target phages. However, most of the current methods only utilize lower-order biological information without considering the higher-order connectivity patterns, which helps to improve the predictive accuracy. Therefore, we developed a novel microbial heterogeneous interaction network (MHIN)-based model called PTBGRP to predict new phages for bacterial hosts. Specifically, PTBGRP first constructs an MHIN by integrating phage-bacteria interaction (PBI) and six bacteria-bacteria interaction networks with their biological attributes. Then, different representation learning methods are deployed to extract higher-level biological features and lower-level topological features from MHIN. Finally, PTBGRP employs a deep neural network as the classifier to predict unknown PBI pairs based on the fused biological information. Experiment results demonstrated that PTBGRP achieves the best performance on the corresponding ESKAPE pathogens and PBI dataset when compared with state-of-art methods. In addition, case studies of Klebsiella pneumoniae and Staphylococcus aureus further indicate that the consideration of rich heterogeneous information enables PTBGRP to accurately predict PBI from a more comprehensive perspective. The webserver of the PTBGRP predictor is freely available at http://120.77.11.78/PTBGRP/.
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Bacteriófagos , Infecções Estafilocócicas , Humanos , Aprendizagem , Bactérias , Redes Neurais de ComputaçãoRESUMO
As a histone acetyltransferase, lysine acetyltransferase 8 (KAT8) participates in diverse biological processes. However, the effect of KAT8 on oocyte maturation in mice remains unclear. In this study, we found that mouse oocytes overexpressing Kat8-OE induced maturation failure manifested reduced rates of GVBD and first polar body emission. In addition, immunostaining results revealed that Kat8 overexpressing oocytes showed inappropriate mitochondrial distribution patterns, overproduction of reactive oxygen species (ROS), accumulation of phosphorylated γH2AX, hyperacetylation of α-tubulin, and severely disrupted spindle/chromosome organization. Moreover, we revealed that Kat8 overexpression induced a decline in SOD1 proteins and KAT8's interaction with SOD1 in mouse ovaries via immunoprecipitation. Western blotting data confirmed that Kat8-OE induced downregulation of SOD1 expression, which is a key factor for the decline of oocyte quality in advanced maternal age. Also, the injection of Myc-Sod1 cRNA could partially rescue maternal age-induced meiotic defects in oocytes. In conclusion, our data demonstrated that high level of KAT8 inhibited SOD1 activity, which in turn induced defects of mitochondrial dynamics, imbalance of redox homeostasis, and spindle/chromosome disorganization during mouse oocyte maturation.
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Histona Acetiltransferases , Meiose , Dinâmica Mitocondrial , Oócitos , Animais , Camundongos , Histona Acetiltransferases/metabolismo , Homeostase , Oócitos/citologia , Oócitos/metabolismo , Oxirredução , Fuso Acromático/metabolismo , Superóxido Dismutase-1/genéticaRESUMO
With the guidance of density functional theory (DFT), a high-performance hafnium (Hf) cathode for an air/water vapor plasma torch is designed and the concepts and principles for high performance are elucidated. A quasi-nanocrystalline hexagonal close-packed (HCP) Hf-La2O3 cathode based on these design principles is successfully fabricated via a powder metallurgy route. Under identical voltage and temperature conditions, the thermal emission current density of this quasi-nanocrystalline Hf-La2O3 cathode is ≈20 times greater than that of conventional Hf cathodes. Additionally, its cathodic lifespan is significantly extended. Quasi-nanocrystalline Hf-La2O3 products are manufactured into cathode devices with standard dimensions. This fabrication process is straightforward, requires minimal doped oxides, and is cost-effective. Consequently, the approach offers substantial performance enhancements over traditional Hf melting methods without incurring significantly additional costs.
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PURPOSE: Positron emission tomography (PET) with prostate-specific membrane antigen (PSMA) targeting tracers has emerged as a valuable diagnostic tool for prostate cancer (PCa), androgen deprivation therapy (ADT) stands as the cornerstone treatment for advanced PCa, yet forecasting the response to hormonal therapy poses a significant clinical hurdle. METHODS: In a prospective cohort of 86 PCa patients undergoing short-term ADT, this study evaluated the prognostic potential of [18F]DCFPyL PET/CT scans. Comprehensive data encompassing clinical profiles, baseline prostate-specific antigen (PSA) levels, and imaging metrics were assessed. We developed predictive models for assessing decreases in PSA levels (PSA50 and PSA70) based on a combination of PET-related parameters and clinical factors. Kaplan-Meier survival analysis was utilized to ascertain the prognostic value of PET-based metrics. RESULTS: In this study, elevated [18F]DCFPyL uptake within the primary tumor, as indicated by a SUV ≥ 6.78 (p = 0.0024), and a reduction in the tumor volume (TV) of primary PSMA-avid tumor with PSMA-TV < 41.96 cm3 (p = 0.038), as well as an increased burden of metastatic PSMA-avid tumor, with PSMA-TV (PSMA-TV ≥ 71.39 cm3) (p = 0.012) were identified in association with diminished progression-free survival (PFS). PET and clinical parameters demonstrated constrained predictive capacity for PSA50 response as indicated by an area under the curve (AUC) of 0.442. CONCLUSION: Our study revealed that pretreatment [18F]DCFPyL uptake in primary or metastatic tumor sites is prognostically relevant in high-risk PCa patients undergoing ADT. Further research is needed to develop robust predictive models in this multifaceted landscape of PCa management.
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Lisina , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Antígeno Prostático Específico , Neoplasias da Próstata , Ureia , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Idoso , Antígeno Prostático Específico/sangue , Lisina/análogos & derivados , Ureia/análogos & derivados , Ureia/uso terapêutico , Pessoa de Meia-Idade , Antagonistas de Androgênios/uso terapêutico , Recidiva , Resultado do TratamentoRESUMO
BACKGROUND: Neuroepithelial transforming gene 1 (NET1) is a RhoA subfamily guanine nucleotide exchange factor that governs a wide array of biological processes. However, its roles in meiotic oocyte remain unclear. We herein demonstrated that the NET1-HACE1-RAC1 pathway mediates meiotic defects in the progression of oocyte maturation. METHODS: NET1 was reduced using a specific small interfering RNA in mouse oocytes. Spindle assembly, chromosomal alignment, the actin cap, and chromosomal spreads were visualized by immunostaining and analyzed under confocal microscopy. We also applied mass spectroscopy, and western blot analysis for this investigation. RESULTS: Our results revealed that NET1 was localized to the nucleus at the GV stage, and that after GVBD, NET1 was localized to the cytoplasm and predominantly distributed around the chromosomes, commensurate with meiotic progression. NET1 resided in the cytoplasm and significantly accumulated on the spindle at the MI and MII stages. Mouse oocytes depleted of Net1 exhibited aberrant first polar body extrusion and asymmetric division defects. We also determined that Net1 depletion resulted in reduced RAC1 protein expression in mouse oocytes, and that NET1 protected RAC1 from degradation by HACE1, and it was essential for actin dynamics and meiotic spindle formation. Importantly, exogenous RAC1 expression in Net1-depleted oocytes significantly rescued these defects. CONCLUSIONS: Our results suggest that NET1 exhibits multiple roles in spindle stability and actin dynamics during mouse oocyte meiosis.
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Actinas , Fuso Acromático , Animais , Camundongos , Actinas/metabolismo , Meiose , Oncogenes , Oócitos/metabolismo , Fuso Acromático/metabolismoRESUMO
As an E3 ubiquitin ligase, F-box and leucine-rich repeat protein 5 (FBXL5) participates in diverse biologic processes. However, the role of Fbxl5 in mouse oocyte meiotic maturation has not yet been fully elucidated. The present study revealed that mouse oocytes depleted of Fbxl5 were unable to complete meiosis, as Fbxl5 silencing led to oocyte meiotic failure with reduced rates of GVBD and polar body extrusion. In addition, Fbxl5 depletion induced aberrant mitochondrial dynamics as we noted the overproduction of reactive oxygen species (ROS) and the accumulation of phosphorylated γH2AX with Fbxl5 knockdown. We also found that Fbxl5-KD led to the abnormal accumulation of CITED2 proteins in mouse oocytes. Our in vitro ubiquitination assay showed that FBXL5 interacted with CITED2 and that it mediated the degradation of CITED2 protein through the ubiquitination-proteasome pathway. Collectively, our data revealed critical functions of FBXL5 in redox hemostasis and spindle assembly during mouse oocyte maturation.
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Proteínas F-Box , Ubiquitina-Proteína Ligases , Animais , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Meiose , Proteínas/metabolismo , Oócitos/metabolismo , Homeostase , Fuso Acromático/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/metabolismoRESUMO
Recently, polyurethane elastomer (TPU) has attracted more and more attention depending on its excellent optical, mechanical, and retreatment properties. The high strength of polyurethane has always been pursued, which can enable its application in more fields. In this work, an aliphatic polyurethane elastomer membrane (HRPU6) was successfully synthesized, and its strength was obviously improved by solvent annealing technology. The tensile strength and adhesion strength can reach 64.56 and 2.58 MPa, but 36.55 and 1.57 MPa only before solvent annealing, respectively. The impact strength of laminated glass based on HRPU has also been significantly improved after solvent annealing, confirmed through drop ball impact testing. It has been confirmed that the increase in strength of HRPU6 is attributed to the enhancement of hydrogen bonding and the improvement of the phase separation degree.
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The present study was designed to explore the function of FAM172A in liver regeneration and HCC. Mice were sacrificed after 70% partial hepatectomy (PH). RNA sequencing was performed on primary hepatocytes of WT and FAM172A-/- mice. We used HepG2 cells to construct cell lines with stably knockdown and overexpression of FAM172A. The expression of FAM172A in liver tissues was investigated by immunohistochemical staining, and we also used public database to perform survival analysis and prognostic model in HCC. Compared with WT mice after PH, normalized liver weight/body weight (LW/BW) ratio and the proliferating cell nuclear antigen (PCNA) protein level of FAM172A-/- mice elevated. The DEGs were mainly enriched in inflammatory response, tumor necrosis factor production, and wound healing. FAM172A knockdown enhanced the NFκB-TNFα and pERK-YAP1-Cyclin D1 axis. FAM172A peptide inhibited proliferation of primary hepatocytes. Moreover, the low expression of FAM172A in human HCC tissues implies a lower likelihood of survival and a valid diagnostic marker for HCC. Loss of FAM172A gene promotes cell proliferation by pERK-YAP1-Cyclin D1 and pNFκB-TNFα pathways during liver regeneration after PH. FAM172A may be a favorable diagnosis marker of HCC.
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Current studies have demonstrated that microbe-host interactions (MHIs) play important roles in human public health. Therefore, identifying the interactions between microbes and hosts is beneficial to understanding the role of the microbiome and their underlying mechanisms. However, traditional wet-lab experimental approaches are insufficient for large-scale exploration of candidate microbes, as they are costly, laborious, and time-consuming. Thus, it is critical to prioritize microbe-interacting hosts by computational approaches for further biological experimental validation. In this work, we proposed a novel deep learning-based method called MHIPM, to predict MHIs by utilizing multisource biological information. Specifically, we first constructed a heterogeneous microbial network that consisted of human proteins, viruses, bacteriophages (phages), and pathogenic bacteria. Next, we used one of the largest protein language models, ESM-2, and a document embedding model, doc2vec, combined with a self-attention mechanism to extract the interview features from protein sequences. Then, an inductive learning-based model, GraphSAGE, was used to capture the intraview features from the heterogeneous network. Experimental results on three prediction tasks indicated that the MHIPM model consistently achieved better performance than seven baseline algorithms and its four variants. In addition, case studies and molecular docking experiments for two human proteins further confirmed the effectiveness of our model. In conclusion, MHIPM is an efficient and robust method in predicting MHIs and provides plausible candidate microbes for biological experiments. MHIPM is available at https://github.com/JIENWU/MHIPM.
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Aprendizado Profundo , Humanos , Interações entre Hospedeiro e Microrganismos , Bactérias/metabolismo , Biologia Computacional/métodos , Interações Hospedeiro-PatógenoRESUMO
BACKGROUND AND OBJECTIVES: Periodontitis is an immuno-inflammatory disease caused by dental plaque biofilms and inflammations. The regeneration of bone tissue in inflammatory environment is of great significance for the treatment of periodontal disease, but the specific molecular mechanism of bone formation in periodontitis still needs further exploration. The objective of this study was to identify key osteogenesis-related genes (ORGs) in periodontitis. METHODS: We used two datasets from the Gene Expression Omnibus (GEO) database to find differentially expressed mRNAs and miRNAs, further performed Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Then we predicted the downstream genes of the differentially expressed miRNAs (DEMs) by the TargetScan database and established a miRNA-mRNA regulatory network. Finally, the osteogenic mechanism of periodontitis was explored through quantitative real-time PCR (qRT-PCR) by inducing inflammatory environment and osteogenic differentiation of hPDLSCs. RESULTS: Through differential expression analysis and prediction of downstream target genes of DEMs, we created a miRNA-mRNA regulatory network consisting of 29 DEMs and 11 differentially expressed osteogenesis-related genes (DEORGs). In addition, the qRT-PCR results demonstrated that BTBD3, PLAT, AKAP12, SGK1, and GLCE expression levels were significantly upregulated, while those of TIMP3, ZCCHC14, LIN7A, DNAH6, NNT, and ITGA6 were downregulated under the dual effects of inflammatory stimulation and osteogenic induction. CONCLUSION: DEORGs might be important factors in the osteogenic phase of periodontitis, and the miRNA-mRNA network may shed light on the clarification of the role and mechanism of osteogenesis in periodontitis and contribute to the development of novel therapeutic strategies.
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MicroRNAs , Periodontite , Humanos , Osteogênese/genética , Ligamento Periodontal , Células-Tronco , Diferenciação Celular/genética , Periodontite/genética , Periodontite/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células Cultivadas , Proteínas de Membrana/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/farmacologia , Proteínas do Tecido Nervoso/metabolismoRESUMO
BACKGROUND: The prevalence of hypertensive heart disease (HHD) is high and there is currently no easy way to detect early HHD. Explore the application of radiomics using cardiac magnetic resonance (CMR) non-enhanced cine sequences in diagnosing HHD and latent cardiac changes caused by hypertension. METHODS: 132 patients who underwent CMR scanning were divided into groups: HHD (42), hypertension with normal cardiac structure and function (HWN) group (46), and normal control (NOR) group (44). Myocardial regions of the end-diastolic (ED) and end-systolic (ES) phases of the CMR short-axis cine sequence images were segmented into regions of interest (ROI). Three feature subsets (ED, ES, and ED combined with ES) were established after radiomic least absolute shrinkage and selection operator feature selection. Nine radiomic models were built using random forest (RF), support vector machine (SVM), and naive Bayes. Model performance was analyzed using receiver operating characteristic curves, and metrics like accuracy, area under the curve (AUC), precision, recall, and specificity. RESULTS: The feature subsets included first-order, shape, and texture features. SVM of ED combined with ES achieved the highest accuracy (0.833), with a macro-average AUC of 0.941. AUCs for HHD, HWN, and NOR identification were 0.967, 0.876, and 0.963, respectively. Precisions were 0.972, 0.740, and 0.826; recalls were 0.833, 0.804, and 0.863, respectively; and specificities were 0.989, 0.863, and 0.909, respectively. CONCLUSIONS: Radiomics technology using CMR non-enhanced cine sequences can detect early cardiac changes due to hypertension. It holds promise for future use in screening for latent cardiac damage in early HHD.
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Diagnóstico Precoce , Hipertensão , Imagem Cinética por Ressonância Magnética , Humanos , Feminino , Masculino , Imagem Cinética por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Hipertensão/diagnóstico por imagem , Hipertensão/complicações , Máquina de Vetores de Suporte , Cardiopatias/diagnóstico por imagem , Idoso , Adulto , Teorema de Bayes , Curva ROC , Interpretação de Imagem Assistida por Computador/métodos , RadiômicaRESUMO
Here, we present a physiologically relevant model of the human pulmonary alveoli. This alveolar lung-on-a-chip platform is composed of a three-dimensional porous hydrogel made of gelatin methacryloyl with an inverse opal structure, bonded to a compartmentalized polydimethylsiloxane chip. The inverse opal hydrogel structure features well-defined, interconnected pores with high similarity to human alveolar sacs. By populating the sacs with primary human alveolar epithelial cells, functional epithelial monolayers are readily formed. Cyclic strain is integrated into the device to allow biomimetic breathing events of the alveolar lung, which, in addition, makes it possible to investigate pathological effects such as those incurred by cigarette smoking and severe acute respiratory syndrome coronavirus 2 pseudoviral infection. Our study demonstrates a unique method for reconstitution of the functional human pulmonary alveoli in vitro, which is anticipated to pave the way for investigating relevant physiological and pathological events in the human distal lung.
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Dispositivos Lab-On-A-Chip , Modelos Biológicos , Alvéolos Pulmonares/fisiologia , Células Epiteliais Alveolares , Antivirais/farmacologia , Fumar Cigarros/efeitos adversos , Dimetilpolisiloxanos/química , Gelatina/química , Humanos , Hidrogéis/química , Metacrilatos/química , Porosidade , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/patologia , Respiração , Mucosa Respiratória/citologia , Mucosa Respiratória/fisiologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidadeRESUMO
Based on the one strain many compounds strategy, a new brominated isocoumarin, 5-bromo-6,8-dihydroxy-3,7-dimethylisocoumarin (1), along with four new natural products, methyl 3-bromo-2,4-dihydroxy-6-methylbenzoate (2), methyl 2-bromo-4,6-dihydroxybenzoate (3), (E)-3-(3-bromo-4-hydroxyphenyl) acrylic acid (4) and 4-hydroxy-3-methyl-6-phenyl-2H-pyran-2-one (5), and four known compounds, methyl orsellinate (6), 4-hydroxy-3-methyl-6-(1-methyl-1-propenyl)-2H-pyran-2-one (7), pilobolusate (8) and cis-ferulic acid (9), were isolated from the ethyl acetate extract of the fungus Aspergillus sp. WXF1904 under the condition of adding bromine salt to the production medium. The structures of the new compounds were established by analysis of NMR and MS data. Compounds (1-9) were evaluated for inhibitory activity of acetylcholinesterase and pancreatic lipase, the new compound 1, known compounds 6 and 7 displayed weak inhibitory activity against acetylcholinesterase, compounds 2, 5, 7 and 8 showed weak inhibitory activity against pancreatic lipase.
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Acetilcolinesterase , Isocumarinas , Aspergillus/química , Fungos , Isocumarinas/química , Lipase , Estrutura Molecular , Benzoatos/químicaRESUMO
Walnut (Juglans regia Linn.) leaf scorch (WLS) was first reported in 2012 in Hotan, Xinjiang, China (Zhang et al., 2012). Initially, brown spots appear at the apex of the leaflets with slight shrinking. These spots spread inward along the leaf margins in a flame-like pattern. The scorched areas curl inward with a yellow halo. No powdery or bacterial signs were observed on the leaf surface. In severe cases, the leaves dried up and shrank, affecting the entire tree. However, new leaves did not show any signs of scorching. We collected 300 symptomatic leaf samples from 10-12 year-old trees of the susceptible WLS species Wen185, located in Daryaboyi (40°72'N, 80°49'E), Xakal (40°69'N, 80°52'E), and Karatal (40°73'N, 80°39'E) for X. fastidiosa PCR detection analysis. X. fastidiosa was detected in asymptomatic leaves of trees with severe WLS, as well as in asymptomatic leaves of trees exhibiting mild WLS symptoms, and it was even found in asymptomatic leaves of trees without any WLS symptoms.To isolate X. fastidiosa, walnut leaves with petioles were disinfected with 3% bleach for 10 minutes, followed by four washes in autoclaved deionized water. The midrib and petiole of the leaf were cut off with a sterile blade, and a 2 mm to 3 mm section was excised. Then, the cut ends were squeezed with a pair of pliers, and the sap was blotted onto Periwinkle Wilt (PW) plates (Davis et al. 1983). The plates were sealed with parafilm and incubated at 28°C in the dark, with daily observations for the development of individual colonies. The sap collected from 5 out of 20 leaf samples with scorch symptoms and from 20 leaves without symptoms never showed bacterial growth in PW.. Six colonies were tested and confirmed positive for X. fastidiosa using the RST31 and RST33 primer pair (Minsavage et al., 1994). The uploaded sequence accession numbers are PP871340-PP871342. Blast analysis of Multilocus Sequence Typing (MLST) sequences from the isolated strain using the X. fastidiosa MLST Database (http://pubmlst.org/xfastidiosa) revealed a perfect match with sequences of alleles leuA_3, petC_3, malF_, cysG_3, holC_4, nuoL_3, and gltT_3 (PP871343-PP871349). Using MEGA software to concatenate the MLST single gene fragments and construct a ML multi-gene fragment phylogenetic tree through Maximum Likelihood (ML) analysis, the bacterium was identified as X. fastidiosa subsp. multiplex To fulfill Koch's postulates, a purified colony from the PW plate was suspended in 500 µL of deionized water at 1×10^8 CFU·mL-1. A sterilized 5 ml medical needle was used to prick a small hole on the main branch, 5 cm from the base, of three-year-old walnut seedlings, and the bacterial solution was injected into the small hole. Three biological replicates were performed for each treatment (5 µL and 10 µL of bacterial solution, deionized water), and the experiment was repeated three times. Scorching symptoms were observed three months after inoculation in 11 out of the 15 seedlings inoculated with a 10 µL bacterial solution, and isolation of X. fastidiosa occurred in leaf samples from 5 of these seedlings, completing Koch's postulates. Walnut seedlings with water stayed asymptomatic, PCR negative. To our knowledge, X. fastidiosa has been found infecting grapes (Chu, 2001) in Shaanxi, China and pears (Su et al., 2016) in Taiwan, China. This is the first report of X. fastidiosa involvement in WLS in China. Further research on the occurrence of the disease will help prevent the spread of the disease.
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Ginkgo (Ginkgo biloba L.), the oldest existing tree species in the world, is an important ornamental and medicinal plant, widely planted in China. In October 2022, a new leaf blight disease was observed in Chengdu city (30°05'to 31°26'N, 102°54'to 104°53'E). Disease incidence averaged 82.5% across five foci. The typical symptomatology begins when leaf margins turn yellow and small black spots appear at the edge of the leaf, chlorotic areas turn brown, dry and deformed. Gradually, the necrotic lesions spreads to the middle of the leaf and eventually the whole leaf falls off. Infected tissues from ten leaves were cut into small pieces (5 × 5 mm); surface sterilized for 30 s in 3% sodium hypochlorite; 60 s in 75% ethanol; rinsed three times in sterile water; placed onto potato dextrose agar (PDA) amended with streptomycin sulfate (50 µg/mL); and incubated at 25°C for 3 to 8 days. A hyphae was removed from the edge of the fungal colony and placed onto potato dextrose agar (PDA) plates. After incubation at 25â with a 12-hour light/dark cycle for 8 days, the colony diameter reached 77.5 to 81.5 mm. Colonies grown on PDA were white, cotton, flocculent, undulating on the surface, dense in aerial hyphae and light yellow on the back. Black pycnidia formed superficially, scattered over the PDA, following two weeks of incubation. Pycnidia contained sticky black conidia. The spores were were spindle shaped, with five cells, and four septations measuring 20.9 to 34.8 µm × 6.8 to 8.8 µm (avg. 28.4 × 7.6 µm; n=40). The three median cells were versicolored, typically two dark brown cells and one light brown cell, whereas the basal and apical cells were hyaline. Conidia had a single basal appendage (2.87 to 4.1 µm long; n = 40) and two to three apical appendages (18.3 to 29.1 µm long; n = 40). Based on colony and conidial morphology, the isolate was identified as N. clavispora (Maharachchikumbura et al. 2014). The partial sequence of the internal transcribed spacer (ITS), ß-tubulin gene (TUB2), and translation elongation factor subunit 1-a gene (TEF1) were amplified and sequenced using the universal primer pairs ITS1/ITS4(Zhang et al. 2022), BT2A/BT2B (Li Yuan et al. 2022), and EF1-526F/EF1-1567R (Maharachchikumbura et al. 2012), respectively. Sequences of representative isolate LQYX were deposited in GenBank (ITS: OQ152504, TUB: OQ168328, and TEF1: OQ168329). BLAST results indicated that the ITS, TUB, and TEF1-α sequences showed 99 to 100% identity with N. clavispora sequences at NCBI (GenBank MG729689, MG740735, and MG740758). Identification was confirmed by Bayesian inference using Mr. Bayes. Next, inoculations were conducted on leaves of ten G. biloba in the field to verify the pathogenicity of LQYX. Ten healthy leaves of each plant were surface sterilized with 75% ethanol, and the wound was rubbed out on the leaf edge on the sterilized sanding paper. A conidia suspension (1 × 107 ml-1) was sprayed on the leaves, aseptic water was used as the control, and the transparent plastic bag was used to maintain relative humidity. After 14 days (26 â, 14 hours light / 10 hours dark), the inoculated leaves had similar symptoms as the original diseased plants, whereas controls were asymptomatic. The N. clavispora was re-isolated from the infected leaves and identified by morphological characteristics and DNA sequence analysis. The pathogenicity test was repeated three times with similar results, confirming Koch's postulates. To our knowledge, this is the first report of leaf blight of G. biloba caused by N. clavispora in China, which has greatly affected the appearance of the city and should be further studied. This report can help identify this disease and further develop effective control measures.
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The point cloud segmentation method plays an important role in practical applications, such as remote sensing, mobile robots, and 3D modeling. However, there are still some limitations to the current point cloud data segmentation method when applied to large-scale scenes. Therefore, this paper proposes an adaptive clustering segmentation method. In this method, the threshold for clustering points within the point cloud is calculated using the characteristic parameters of adjacent points. After completing the preliminary segmentation of the point cloud, the segmentation results are further refined according to the standard deviation of the cluster points. Then, the cluster points whose number does not meet the conditions are further segmented, and, finally, scene point cloud data segmentation is realized. To test the superiority of this method, this study was based on point cloud data from a park in Guilin, Guangxi, China. The experimental results showed that this method is more practical and efficient than other methods, and it can effectively segment all ground objects and ground point cloud data in a scene. Compared with other segmentation methods that are easily affected by parameters, this method has strong robustness. In order to verify the universality of the method proposed in this paper, we test a public data set provided by ISPRS. The method achieves good segmentation results for multiple sample data, and it can distinguish noise points in a scene.
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Existing point-to-point registration methods often suffer from inaccuracies caused by erroneous matches and noisy correspondences, leading to significant decreases in registration accuracy and efficiency. To address these challenges, this paper presents a new coarse registration method based on a geometric constraint and a matrix evaluation. Compared to traditional registration methods that require a minimum of three correspondences to complete the registration, the proposed method only requires two correspondences to generate a transformation matrix. Additionally, by using geometric constraints to select out high-quality correspondences and evaluating the matrix, we greatly increase the likelihood of finding the optimal result. In the proposed method, we first employ a combination of descriptors and keypoint detection techniques to generate initial correspondences. Next, we utilize the nearest neighbor similarity ratio (NNSR) to select high-quality correspondences. Subsequently, we evaluate the quality of these correspondences using rigidity constraints and salient points' distance constraints, favoring higher-scoring correspondences. For each selected correspondence pair, we compute the rotation and translation matrix based on their centroids and local reference frames. With the transformation matrices of the source and target point clouds known, we deduce the transformation matrix of the source point cloud in reverse. To identify the best-transformed point cloud, we propose an evaluation method based on the overlap ratio and inliers points. Through parameter experiments, we investigate the performance of the proposed method under various parameter settings. By conducting comparative experiments, we verified that the proposed method's geometric constraints, evaluation methods, and transformation matrix computation consistently outperformed other methods in terms of root mean square error (RMSE) values. Additionally, we validated that our chosen combination for generating initial correspondences outperforms other descriptor and keypoint detection combinations in terms of the registration result accuracy. Furthermore, we compared our method with several feature-matching registration methods, and the results demonstrate the superior accuracy of our approach. Ultimately, by testing the proposed method on various types of point cloud datasets, we convincingly established its effectiveness. Based on the evaluation and selection of correspondences and the registration result's quality, our proposed method offers a solution with fewer iterations and higher accuracy.
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A 33-year-old female patient was admitted to our hospital 5 h after developing sudden unclear vision in her left eye following injection of hyaluronic acid (periorbital dermis of the left eye) into the frown lines. She was diagnosed with acute retinal artery occlusion and underwent emergency cerebral angiography and hyaluronidase intervention for vascular recanalization treatment. In addition, she received postoperative neurotrophic treatment, as well as therapies to improve circulation, eliminate edema, and hyperbaric oxygen therapy. These treatments transformed left eye vision (from hand movement to a central visual acuity of 0.5). This study highlights a potential complication of hyaluronic acid injections using blunt needles: vascular embolization. Given this risk, health-care providers should exercise extreme caution during the injection procedure. In addition, prompt intervention is crucial in cases of embolization.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.