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The H9N2 avian influenza virus (AIV) represents a significant risk to both the poultry industry and public health. Our surveillance efforts in China have revealed a growing trend of recent H9N2 AIV strains exhibiting a loss of hemagglutination activity at 37°C, posing challenges to detection and monitoring protocols. This study identified a single K141N substitution in the hemagglutinin (HA) glycoprotein as the culprit behind this diminished hemagglutination activity. The study evaluated the evolutionary dynamics of residue HA141 and studied the impact of the N141K substitution on aspects such as virus growth, thermostability, receptor-binding properties, and antigenic properties. Our findings indicate a polymorphism at residue 141, with the N variant becoming increasingly prevalent in recent Chinese H9N2 isolates. Although both wild-type and N141K mutant strains exclusively target α,2-6 sialic acid receptors, the N141K mutation notably impedes the virus's ability to bind to these receptors. Despite the mutation exerting minimal influence on viral titers, antigenicity, and pathogenicity in chicken embryos, it significantly enhances viral thermostability and reduces plaque size on Madin-Darby canine kidney (MDCK) cells. Additionally, the N141K mutation leads to decreased expression levels of HA protein in both MDCK cells and eggs. These findings highlight the critical role of the K141N substitution in altering the hemagglutination characteristics of recent H9N2 AIV strains under elevated temperatures. This emphasizes the need for ongoing surveillance and genetic analysis of circulating H9N2 AIV strains to develop effective control and prevention measures.IMPORTANCEThe H9N2 subtype of avian influenza virus (AIV) is currently the most prevalent low-pathogenicity AIV circulating in domestic poultry globally. Recently, there has been an emerging trend of H9N2 AIV strains acquiring increased affinity for human-type receptors and even losing their ability to bind to avian-type receptors, which raises concerns about their pandemic potential. In China, there has been a growing number of H9N2 AIV strains that have lost their ability to agglutinate chicken red blood cells, leading to false-negative results during surveillance efforts. In this study, we identified a K141N mutation in the HA protein of H9N2 AIV to be responsible for the loss of hemagglutination activity. This finding provides insight into the development of effective surveillance, prevention, and control strategies to mitigate the threat posed by H9N2 AIV to both animal and human health.
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Sustitución de Aminoácidos , Hemaglutinación , Glicoproteínas Hemaglutininas del Virus de la Influenza , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Mutación , Animales , Embrión de Pollo , Perros , Humanos , Pollos/virología , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H9N2 del Virus de la Influenza A/inmunología , Subtipo H9N2 del Virus de la Influenza A/metabolismo , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Gripe Aviar/virología , Aves de Corral , Femenino , Ratones , Línea Celular , Evolución Molecular , Temperatura , Receptores Virales/metabolismoRESUMEN
Development of mRNA therapeutics necessitates targeted delivery technology, while the clinically advanced lipid nanoparticles face difficulty for extrahepatic delivery. Herein, we design highly branched poly(ß-amino ester)s (HPAEs) for efficacious organ-selective mRNA delivery through tailoring their chemical compositions and topological structures. Using an "A2+B3+C2" Michael addition platform, a combinatorial library of 219 HPAEs with varied backbone structures, terminal groups, and branching degrees are synthesized. The branched topological structures of HPAEs provide enhanced serum resistance and significantly higher mRNA expression in vivo. The terminal amine structures of HPAEs determine the organ-selectivity of mRNA delivery following systemic administration: morpholine facilitates liver targeting, ethylenediamine favors spleen delivery, while methylpentane enables mRNA delivery to the liver, spleen, and lungs simultaneously. This study represents a comprehensive exploration of the structure-activity relationship governing both the efficiency and organ-selectivity of mRNA delivery by HPAEs, suggesting promising candidates for treating various organ-related diseases.
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Polímeros , ARN Mensajero , ARN Mensajero/genética , Animales , Humanos , Polímeros/química , Ratones , Nanopartículas/química , Hígado/metabolismo , Bazo/metabolismo , Técnicas de Transferencia de Gen , Pulmón/metabolismoRESUMEN
This study aimed to screen for key genes related to the prognosis of patients with glioblastoma (GBM). First, bioinformatics analysis was performed based on databases such as TCGA and MSigDB. Inflammatory-related genes were obtained from the MSigDB database. The TCGA-tumor samples were divided into cluster A and B groups based on consensus clustering. Multivariate Cox regression was applied to construct the risk score model of inflammatory-related genes based on the TCGA database. Second, to understand the effects of model characteristic genes on GBM cells, U-87 MG cells were used for knockdown experiments, which are important means for studying gene function. PLAUR is an unfavorable prognostic biomarker for patients with glioma. Therefore, the model characteristic gene PLAUR was selected for knockdown experiments. The prognosis of cluster A was significantly better than that of cluster B. The verification results also demonstrate that the risk score could predict overall survival. Although the immune cells in cluster B and high-risk groups increased, no matching survival advantage was observed. It may be that stromal activation inhibits the antitumor effect of immune cells. PLAUR knockdown inhibits tumor cell proliferation, migration, and invasion, and promoted tumor cell apoptosis. In conclusion, a prognostic prediction model for GBM composed of inflammatory-related genes was successfully constructed. Increased immune cell expression may be linked to a poor prognosis for GBM, as stromal activation decreased the antitumor activity of immune cells in cluster B and high-risk groups. PLAUR may play an important role in tumor cell proliferation, migration, invasion, and apoptosis.
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Glioblastoma , Glioma , Humanos , Glioblastoma/genética , Pronóstico , Puntuación de Riesgo Genético , Factores de RiesgoRESUMEN
BACKGROUND: A better diagnostic marker is in need to distinguish breast cancer from suspicious breast lesions. The abnormal glycosylation of haptoglobin has been documented to assist cancer diagnosis. This study aims to evaluate disease-specific haptoglobin (DSHp)-ß N-glycosylation as a potential biomarker for breast cancer diagnosis. METHODS: DSHp-ß chains of 497 patients with suspicious breast lesions who underwent breast surgery were separated from serum immunoinflammatory-related protein complexes. DSHp-ß N-glycosylation was quantified by mass spectrometric analysis. After missing data imputation and propensity score matching, patients were randomly assigned to the training set (n = 269) and validation set (n = 113). Logistic regression analysis was employed in model and nomogram construction. The diagnostic performance was analyzed with receiver operating characteristic and calibration curves. RESULTS: 95 N-glycopeptides at glycosylation sites N207/N211, N241, and N184 were identified in 235 patients with benign breast diseases and 262 patients with breast cancer. DSHp-ß N-tetrafucosyl and hexafucosyl were significantly increased in breast cancer compared with benign diseases (p < 0.001 and p = 0.001, respectively). The new diagnostic model and nomogram included GN2F2, G6N3F6, GN2FS at N184, G-N&G2S2, G2&G3NFS, G2N3F, GN3 at N207/N211, CEA, CA153, and could reliably distinguish breast cancer from benign diseases. For the training set, validation set, and training and validation sets, the area under the curves (AUCs) were 0.80 (95% CI: 0.75-0.86, specificity: 87%, sensitivity: 62%), 0.77 (95% CI:0.69-0.86, specificity: 75%, sensitivity: 69%), and 0.80 (95% CI:0.76-0.84, specificity: 77%, sensitivity: 68%), respectively. CEA, CA153, and their combination yielded AUCs of 0.62 (95% CI: 0.56-0.67, specificity: 29%, sensitivity: 90%), 0.65 (95% CI: 0.60-0.71, specificity: 74%, sensitivity: 51%), and 0.67 (95% CI: 0.62-0.73, specificity: 60%, sensitivity: 68%), respectively. CONCLUSIONS: The combination of DSHp-ß N-glycopeptides, CEA, and CA153 might be a better serologic marker to differentiate between breast cancer and benign breast diseases. The dysregulated N-glycosylation of serum DSHp-ß could provide insights into breast tumorigenesis.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Nomogramas , Haptoglobinas/química , Glicosilación , Glicopéptidos/análisisRESUMEN
Poly(ethylene glycol) (PEG)-based hydrogels are particularly challenging to degrade, which hinders efficient cell harvesting within the gel matrix. Here, highly branched copolymers of PEG methyl ether acrylate (PEGMA) and disulfide diacrylate (DSDA) (PEG-DS) with short primary chains and multiple pendent vinyl groups were synthesized by a "vinyl oligomer combination" approach. PEG-DS readily cross-links with thiolated gelatin (Gel-SH) to form hydrogels. Results demonstrate that shortening the primary chains of PEG-DS significantly enhances the viability of bone marrow mesenchymal stem cells (BMSCs) by up to 193.2%. Importantly, DS junctions can be easily cleaved into short primary chains using dithiothreitol (DTT), triggering ultrafast degradation of PEG-DS/Gel-SH hydrogels within 2 min under mild conditions and release of the encapsulated BMSCs. This study establishes a novel strategy to enhance the degradation of acrylate-based PEG hydrogels for three-dimensional (3D) cell culture and harvesting. These findings expand the potential applications of such hydrogels in various biomedical fields.
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OBJECTIVE: Inadequate tuberculosis (TB) knowledge and awareness of proper TB control practices among health care workers (HCWs) may increase the risk of nosocomial TB transmission. This study aimed to assess HCWs' TB-related knowledge and control practices to guide the development of more effective targeted TB health education and training programs. METHODS: In January 2023 a cross-sectional survey was administered to 323 HCWs employed by five primary health care centers and three secondary comprehensive medical institutions in Beijing, China. Survey data were collected using a standard questionnaire. RESULTS: Analysis of survey responses revealed TB knowledge and practices awareness rates of 60.4% and 90.6%, respectively. The overall average awareness rate across all 19 TB knowledge- and practice-related questions was 70.0%. Intermediate- and senior-level HCW's average TB knowledge score was respectively 2.225 and 8.175 times higher than that of primary-level HCWs, while the average TB knowledge score of HCWs in secondary comprehensive medical institutions was 3.052 times higher than that of HCWs in primary health care centers. Higher average TB knowledge score correlated with higher-level professional titles and higher level work units, but higher average TB control practices score correlated with employment at primary health care center rather than secondary comprehensive medical institution. Notably, 13.6% of HCWs had not received TB training during the past three years, while 86.1% expressed willingness to undergo online TB training. CONCLUSION: These findings highlight inadequate TB knowledge and awareness of proper TB control practices among HCWs in primary health care centers and secondary comprehensive medical institutions in Beijing, underscoring the urgent need for targeted educational and training initiatives to improve TB awareness and control efforts.
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Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Tuberculosis , Humanos , Estudios Transversales , Personal de Salud/psicología , Personal de Salud/educación , Femenino , Adulto , Masculino , Tuberculosis/prevención & control , Encuestas y Cuestionarios , Beijing , Persona de Mediana Edad , Atención Primaria de Salud , Infección Hospitalaria/prevención & control , Adulto Joven , China , Control de Infecciones/métodosRESUMEN
Microelectromechanical systems (MEMS) gas sensors have numerous advantages such as compact size, low power consumption, ease of integration, etc., while encountering challenges in sensitivity and high resistance because of their low sintering temperature. This work utilizes the in situ growth of Zeolitic Imidazolate Framework-8 (ZIF-8) followed by its conversion to N-doped ZnO. The results obtained from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicate that the in situ derivation of ZIF-8 facilitates the adhesion of ZnO particles, forming an island-like structure and significantly reducing the interfaces between these particles. Furthermore, powder X-ray diffraction (XRD) analysis, elemental mapping, and X-ray photoelectron spectroscopy (XPS) analysis confirm the conversion of ZIF-8 to ZnO, the successful incorporation of N atoms into the ZnO lattice, and the creation of more oxygen vacancies. The ZIF-8-derived N-doped ZnO/MEMS sensor (ZIF (3)-ZnO/MEMS) exhibits remarkable gas sensitivity for ethanol detection. At an operating temperature of 290 °C, it delivers a substantial response value of 80 towards 25 ppm ethanol, a 13-fold enhancement compared with pristine ZnO/MEMS sensors. The sensor also exhibits an ultra-low theoretical detection limit of 11.5 ppb to ethanol, showcasing its excellent selectivity. The enhanced performance is attributed to the incorporation of N-doped ZnO, which generates abundant oxygen vacancies on the sensor's surface, leading to enhanced interaction with ethanol molecules. Additionally, a substantial two-order-of-magnitude decrease in the resistance of the gas-sensitive film is observed. Overall, this study provides valuable insights into the design and fabrication strategies applicable to high-performance MEMS gas sensors in a broader range of gas sensing.
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To date, significant efforts have been dedicated to improve their ionic conductivity, thermal stability, and mechanical strength of solid polymer electrolytes (SPEs). However, direct monitoring of physical and chemical changes in SPEs is still lacking. Moreover, existing thermosetting SPEs are hardly degradable. Herein, by overcoming the limitation predicted by Flory theory, self-reporting and biodegradable thermosetting hyperbranched poly(ß-amino ester)-based SPEs (HPAE-SPEs) are reported. HPAE is successfully synthesized through a well-controlled "A2+B4" Michael addition strategy and then crosslinked it in situ to produce HPAE-SPEs. The multiple tertiary aliphatic amines at the branching sites confer multicolour luminescence to HPAE-SPEs, enabling direct observation of its physical and chemical damage. After use, HPAE-SPEs can be rapidly hydrolysed into non-hazardous ß-amino acids and polyols via self-catalysis. Optimized HPAE-SPE exhibits an ionic conductivity of 1.3×10-4 â S/cm at 60 °C, a Na+ transference number ( t N a + ${{t}_{Na}^{+}}$ ) of 0.67, a highly stable sodium plating-stripping behaviour and a low overpotential of ≈190â mV. This study establishes a new paradigm for developing SPEs by engineering multifunctional polymers. The self-reporting and biodegradable properties would greatly expand the scope of applications for SPEs.
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Aberrant protein glycosylation is an active pathological alteration related to the progression of cancers. The speed of progression varies among individuals, increasing the difficulties of prognosis assessment. Hence, evaluating variation in glycosylation using patients themselves as their own controls is a potential way to reduce the impact of individual differences on progression monitoring. Here, following a longitudinal follow-up study involving 125 lung cancer (LC) patients with progressive disease, we isolated disease-specific IgG from serum using polyacrylamide gel electrophoresis, obtained IgG glycoform ratios using mass spectrometry, and then set a fold-change cutoff of 1.5 to utilize the intra-individual variation in IgG glycosylation to monitor PD. We found that the serial monitoring of 15 types of glycoform ratios provided an effective way for monitoring LC progression. Over 1.5-fold changes in glycoform ratios relative to the first observed value were detected in 117 of 125 LC patients (93.6%). Our established method predicted LC progression 55.8 (IQR 31.1-90.1) weeks earlier than imaging examination did. In summary, intra-individual variation in IgG glycoform ratios is useful to monitor LC progression, expanding our knowledge about the relationship between IgG glycosylation and cancer prognosis. The raw data files are available via the ProteomeXchange Consortium with the identifier PXD037541.
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Inmunoglobulina G , Neoplasias Pulmonares , Humanos , Inmunoglobulina G/metabolismo , Estudios de Seguimiento , Espectrometría de Masas , Neoplasias Pulmonares/diagnóstico , Progresión de la Enfermedad , Fragmentos Fc de InmunoglobulinasRESUMEN
Amino metabolites are essential for life activities and can be used clinically as biomarkers for disease diagnosis and treatment. Solid-phase-supported chemoselective probes can simplify sample handling and enhance detection sensitivity. However, the low efficiency and complicated preparation of traditional probes limit their further application. In this work, a novel solid-phase-supported probe Fe3O4-SiO2-polymers-phenyl isothiocyanate (FSP-PITC) was developed by immobilizing phenyl isothiocyanate on magnetic beads with disulfide as an orthogonal cleavage site, which can couple amino metabolites directly regardless of whether proteins and other matrixes were removed. After purification, the targeted metabolites were released by dithiothreitol and detected by high-resolution mass spectrometry. The simplified processing steps shorten the analysis time, and the introduction of polymers results in a 100-1000-fold increase in probe capacity. With high stability and specificity, FSP-PITC pretreatment allows accurate qualitative and quantitative (R2 > 0.99) analysis, facilitating the detection of metabolites in subfemtomole quantities. Using this strategy, 4158 metabolite signals were detected in negative ion mode. Among them, 352 amino metabolites including human cells (226), serum (227), and mouse samples (274) were searched from the Human Metabolome Database. These metabolites participate in metabolic pathways of amino acids, biogenic amine, and the urea cycle. All these results indicate that FSP-PITC is a promising probe for novel metabolite discovery and high-throughput screening.
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Metaboloma , Dióxido de Silicio , Humanos , Animales , Ratones , Espectrometría de Masas/métodos , Aminas Biogénicas , Metabolómica/métodosRESUMEN
Playing a great role in human physiologies and pathologies, carbonyl metabolites are intimately associated with a variety of diseases, though the effective analysis method of them remains a challenge. A hydrazide-terminated polyurea-modified magnetic particle (HPMP) with versatile probes is developed to address this issue. The capture ability of HPMPs for carbonyl metabolite is more than 1200 µmol g-1 , which is increased by 4 orders of magnitude via the introduction of polyurea. With a broad linear range of over 4 orders of magnitude, remarkably improved sensitivity, and limit of detection at attomole quantities, HPMPs are applied in relative quantification of more than 1500 carbonyl metabolites in 113 human serum samples with high throughput and high coverage. The combined indicators of these metabolites demonstrates a great diagnostic accuracy for distinguishing between health and disease subjects as well as differentiating the patients with benign lung disease and lung cancer. Combining powerful capture ability, low-cost preparation, and convenient operation, the HPMPs demonstrate extensive application in biomarker discovery and the detailed study of the biochemical landscape.
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Neoplasias Pulmonares , Polímeros , Humanos , Neoplasias Pulmonares/metabolismo , Biomarcadores , Fenómenos MagnéticosRESUMEN
This study developed a novel, ultrasensitive sandwich-type electrochemical immunosensor for detecting the porcine epidemic diarrhea virus (PEDV). By electrochemical co-deposition of graphene and Prussian blue, a Prussian blue-reduced graphene oxide-modified glassy carbon electrode was made, further modified with PEDV-monoclonal antibodies (mAbs) to create a new PEDV immunosensor using the double antibody sandwich technique. The electrochemical characteristics of several modified electrodes were investigated using cyclic voltammetry (CV). We optimized the pH levels and scan rate. Additionally, we examined specificity, reproducibility, repeatability, accuracy, and stability. The study indicates that the immunosensor has good performance in the concentration range of 1 × 101.88 to 1 × 105.38 TCID50/mL of PEDV, with a detection limit of 1 × 101.93 TCID50/mL at a signal-to-noise ratio of 3σ. The composite membranes produced via co-deposition of graphene and Prussian blue effectively increased electron transport to the glassy carbon electrode, boosted response signals, and increased the sensitivity, specificity, and stability of the immunosensor. The immunosensor could accurately detect PEDV, with results comparable to real-time quantitative PCR. This technique was applied to PEDV detection and served as a model for developing additional immunosensors for detecting hazardous chemicals and pathogenic microbes.
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Técnicas Biosensibles , Grafito , Virus de la Diarrea Epidémica Porcina , Animales , Porcinos , Carbono , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Reproducibilidad de los Resultados , Inmunoensayo/métodos , Electrodos , Límite de Detección , OroRESUMEN
Advanced oxidation processes (AOPs) hold great prospects for the treatment of antibiotic wastewater. N-doped biochar (NB) has received increasing attention as a catalyst for AOPs because of its green nature, abundant biomass resources, and low cost. However, NB catalysts are complicated to prepare and difficult to recover, limiting their practical application. In this study, an N-doped biochar geopolymer composite (NBGC) was synthesized via in situ doping, simultaneous carbonization, and activation (ISCA) of lignin and urea in the porous geopolymer flake, without additional activators. The ISCA process used a low-cost geopolymer flake that not only served as a carrier to immobilize NB and facilitate the recovery, but also applied its inherent strong alkalinity to activate NB. The composite catalyst obtained at 600 °C (NBGC-600) exhibited excellent activity in activating H2O2 to degrade tetracycline (â¼100%, 50 mg/L). The EPR results indicated that NBGC-600 had a strong ability to activate and decompose H2O2 to â¢OH, which could be attributed to its rich persistent radicals, graphitized N and CO groups, as well as the high degree of graphitization of biochar. The degradation pathway and intermediates of tetracycline in the NBGC-600-H2O2 system were also discussed according to the HPLC-MS results. Moreover, NBGC-600 had excellent reusability and showed great potential for continuous treatment of tetracycline in water. This work paves a new way for the synthesis of cost-effective N-doped biochar composite catalysts for AOPs.
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Peróxido de Hidrógeno , Agua , Antibacterianos , TetraciclinaRESUMEN
The paper presents the results of multiplying the repetition frequency of the seed source to 396 MHz using an extra-cavity fiber multiplication method. The single crystal fiber rod-type amplifier was able to boost the average output power to approximately 15.9 W. Using a transmission gratings-based pulse compressor, an average output power of 9.56 W was achieved, corresponding to a burst energy of up to 382 µJ and a compression efficiency of 81.7%. The shortest pulse duration was optimized to be 594 fs; however, an obvious pedestal was also observed. This system reduces the impact of nonlinear effects on the device by increasing the repetition frequency, thereby increasing the injection energy of a single process in industrial processing.
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The paper describes the observation of diverse bound-state patterns, including tightly bound states, loosely bound states, and composite bound states, in a figure-9 fiber laser. By performing dispersion management and using polarization-maintaining fibers with high gain coefficient, stable dispersion-managed solitons and bound solitons can be simultaneously generated. This work advances our understanding of complex soliton dynamics and presents a novel, to the best of our knowledge, approach for future applications of bound states. Additionally, the research involves integrated packaging, effectively enhancing overall work stability.
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Loquat (Rhaphiolepis biabas, heterotypic synonym: Eriobotrya japonica) is an important edible and medicinal plant that is widely cultivated on 133 thousand hectares (recorded in 2022) in China. A stem brown rot was observed on young and old trees in Mengzi city (23°23' N; 103°23' E), Yunnan Province, southwest China, during October 2014 and September 2021. Incidence ranged from 20% of trees in surrounding plantations to 50% incidence of a 160 tree orchard that was the focal point of the disease survey. Circular brown lesions occurred initially on the stems and gradually covered all the epidermis of the stem, leading to irregular dents within the bark that developed a dark brown powdery appearance (Fig.1A). Larger lesions affected vascular tissues, causing diseased trees to wither and die. Diseased tissues were surface-disinfected in a 5% sodium hypochlorite solution for 3 min, rinsed three times with sterile distilled water, placed on potato dextrose agar (PDA), and incubated in the dark at 28°C. Twenty samples were collected for tissue isolation, and 11 isolates were single-spored on water agar. In culture, the colonies on PDA were white to dark-gray, velvet, with dense hyphae, diameter 7.64 cm after 5 days. After 18 days, spherical or subglobose pycnidia were developed and semi-buried in medium, their walls were thicker and dark-brown, which were black particles surrounded by gray-black hyphae. Conidiogenous cells were hyaline, cylindrical, holoblastic, slightly swollen at the base, with rounded apex. Conidia were initially hyaline and aseptate with elliptic or ovate shape, becoming dark brown with a single septate and developing longitudinal striations along thick walls at maturity. Conidia dimensions varied from 8.0 to 12.2 × 3.8 to 6.1µm (n=50) (Fig.1D). The morphological characteristics of eleven isolates were consistent with the description of Lasiodiplodia theobromae (Alves et al. 2008). Further confirmation was also determined by sequencing the internal transcribed spacer (ITS), ß-tubulin genes, partial translation elongation factor-1α (TEF-1α) (White et al. 1990, Carbone et al. 1999, Glass et al.1995). The isolate LSB-1 was selected for DNA sequence analysis. Based on BLASTn analysis, ITS sequences (OM617921) had 98.3% similarity with L. theobromae CBS164.96 (accession AY640255), CBS124.13(accession DQ458890), CAA006 (accession DQ458891) and CBS111530 (accession EF622074), ß-tubulin sequences (OM643838) showed 99.1% similarity with L. theobromae accessions EU673110. The TEF-1α (OM643839) had 99.0% identity with L. theobromae accession EF633054. The isolate LSB-1 clustered on the same clade with other L. theobromae. Pathogenicity testing of isolate LSB-1, LSB-2, LSB-3 was conducted by inoculating the stems of l-year-old seedlings growing in pots. The epidermis at the inoculation site, 15-20 cm below the crown, was wiped with 75% alcohol cotton ball, washed three times with sterile water, and then punctured (5mm diameter) with sterile inoculation needle. A 5mm block of each isolate cultured on PDA for seven days was attached to the inoculation site. Controls were inoculated with sterile PDA blocks. The inoculation area was covered with polyethylene cling film. All inoculated seedlings were kept in controlled greenhouse at 27°C with 80% relative humidity under natural daylight conditions, and watered weekly. Each treatment was repeated three times. Eight days after inoculation, all diseased plants showed dark brown discoloration at the point of inoculation (Fig. 1G) with the bark at the inoculation site gradually raising as the disease progressed. Thirty days after inoculation, all inoculated seedlings produced typical symptoms, whereas the control seedlings remained healthy. Fungal isolates were only recovered from symptomatic stems and were morphologically identical to L. theobromae, completing Koch's postulates. According to the relevant literature, Lasiodiplodia theobromae has a broad host range, causing numerous diseases, including canker and dieback of branch (Aguilera-Cogley et al., 2021), panicle blight (Mahadevakumar et al, 2022), root rot (Abd-El Ghani and Fatouh, 2005), fruit rot(Freire et al., 2011) in diverse geographical regions. To our knowledge, this is the first report of L. theobromae causing stem brown rot of loquat in China and provides a foundation for further study of the epidemiology and integrated management of this disease.
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The paper studies the secrecy communication threatened by a single eavesdropper in Energy Harvesting (EH)-based cognitive radio networks, where both the Secure User (SU) and the jammer harvest, store, and utilize RF energy from the Primary Transmitter (PT). Our main goal is to optimize the time slots for energy harvesting and wireless communication for both the secure user as well as the jammer to maximize the long-term performance of secrecy communication. A multi-agent Deep Reinforcement Learning (DRL) method is proposed for solving the optimization of resource allocation and performance. Specifically, each sub-channel from the Secure Transmitter (ST) to the Secure Receiver (SR) link, along with the jammer to the eavesdropper link, is regarded as an agent, which is responsible for exploring optimal power allocation strategy while a time allocation network is established to obtain optimal EH time allocation strategy. Every agent dynamically interacts with the wireless communication environment. Simulation results demonstrate that the proposed DRL-based resource allocation method outperforms the existing schemes in terms of secrecy rate, convergence speed, and the average number of transition steps.
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Comunicación , Asignación de Recursos , Fenómenos Físicos , Simulación por Computador , CogniciónRESUMEN
Using inertial measurement units (IMUs) to estimate lower limb joint kinematics and kinetics can provide valuable information for disease diagnosis and rehabilitation assessment. To estimate gait parameters using IMUs, model-based filtering approaches have been proposed, such as the Kalman filter and complementary filter. However, these methods require special calibration and alignment of IMUs. The development of deep learning algorithms has facilitated the application of IMUs in biomechanics as it does not require particular calibration and alignment procedures of IMUs in use. To estimate hip/knee/ankle joint angles and moments in the sagittal plane, a subject-independent temporal convolutional neural network-bidirectional long short-term memory network (TCN-BiLSTM) model was proposed using three IMUs. A public benchmark dataset containing the most representative locomotive activities in daily life was used to train and evaluate the TCN-BiLSTM model. The mean Pearson correlation coefficient of joint angles and moments estimated by the proposed model reached 0.92 and 0.87, respectively. This indicates that the TCN-BiLSTM model can effectively estimate joint angles and moments in multiple scenarios, demonstrating its potential for application in clinical and daily life scenarios.
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Aprendizaje Profundo , Humanos , Extremidad Inferior , Articulación de la Rodilla , Marcha , Rodilla , Fenómenos BiomecánicosRESUMEN
Using detailed exposure information on COVID-19 cases, we estimated the mean latent period to be 5.5 (95% CI: 5.1-5.9) days, shorter than the mean incubation period (6.9 days). Laboratory testing may allow shorter quarantines since 95% of COVID-19 cases shed virus within 10.6 (95% CI: 9.6-11.6) days of infection.
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COVID-19 , Humanos , Cuarentena , SARS-CoV-2RESUMEN
Treprostinil palmitil (TP), a long-acting inhaled pulmonary vasodilator prodrug of treprostinil (TRE), has beneficial effects in a Sugen5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension (PAH) that compare favorably to the oral phosphodiesterase 5 inhibitor (PDE5) sildenafil. In this study in male Sprague-Dawley rats, a dry powder formulation of TP (TPIP) was compared with inhaled and intravenous TRE and oral selexipag to evaluate inhibition of hemodynamic and pathologic changes in the lungs and heart induced by Su/Hx challenge. Su (20 mg/kg) was injected subcutaneously followed by 3 weeks of Hx (10% O2/balance N2) and then initiation of test article administration over 5 weeks with room air breathing. Hemodynamics and histopathology were measured at the end of the study. Su/Hx challenge approximately doubled the mean pulmonary arterial blood pressure (mPAP) and the Fulton index, decreased cardiac output (CO), doubled the wall thickness and muscularization of the small (10-50 µm) and medium (51-100 µm) sized pulmonary arteries, and increased the percentage of obliterated pulmonary blood vessels. Even though inhaled TRE (65 µg/kg, 4× daily), intravenous TRE (810 ng/kg/min), and oral selexipag (30 mg/kg, twice daily) provided some beneficial effects against the Su/Hx challenge, the overall benefit was generally greater with TPIP at high dose (117 µg/kg, once daily). These results demonstrate that TPIP compares favorably to inhaled and intravenous TRE and oral selexipag with respect to inhibition of the pathophysiological changes induced by Su/Hx challenge in rats. SIGNIFICANCE STATEMENT: Treprostinil palmitil (TP) is a long-acting pulmonary vasodilator prodrug of treprostinil (TRE) formulated for inhaled administration by dry powder [treprostinil palmitil inhalation powder (TPIP)]. Comparison of the activity of TPIP, inhaled and intravenous TRE, and oral selexipag in a Sugen5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension demonstrated that each of these drugs exert protection against the hemodynamic and histopathological changes induced by the Su/Hx challenge, with the greatest effect on these changes produced by TPIP.