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1.
Plant Dis ; 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38764341

RESUMEN

In Henan, strawberry cultivation occurs on approximately 10,000 hectares, with annual production approaching 230,000 tons. In April 2022, a root rot disease with a 10% incidence rate was observed on the strawberry cultivars 'Ningyu' and 'Sweet Charlie' grown in plastic greenhouses (0.7 ha) located in Xingyang (113.39°E, 34.79°N), Henan, China. Disease symptoms included yellowing of the outer mature leaves, stunted growth, and subsequent wilting of the entire plant. The roots developed dark brown spots, which gradually turned necrotic (Figures 1a, 1b). To determine the causal agent, four symptomatic plants (two plants per cultivar) were collected. Twelve symptomatic root tissues (three root tissue samples per plant) were surface sterilized with 75% ethanol and 0.1% mercuric chloride, washed thrice in sterile water, air dried, and then placed on PDA at 25°C for 3 days. Eight pure isolates were obtained by hyphal-tip isolation (Fang 2007). Each colony had a dark olivaceous green to brown, cottony appearance with a round margin, and the reverse side was grey-black near the center (Figure 1c). Conidia were ellipsoidal, aseptate, with rounded ends, and 3.1 to 4.8 µm × 1.0 to 2.5 µm in size (Figure 1d). Chlamydospores were ellipsoidal, pale brown, and 7.9 to 11.9 µm × 7.6 to 10.7 µm in size (Figure 1e). A representative fungus isolate, designated as Z5, was selected for further molecular identification. Genomic DNA was extracted from the mycelia of isolate Z5, and four gene partial regions (ITS, TUB2, RPB2, and LSU) were amplified using the primer pairs ITS1/ITS4, Bt-2a/Bt-2b, RPB2-5F/RPB2-7CR and LROR/LR5, respectively (White et al.1990, O'Donnell et al.1997, Reeb et al. 2004, Rehner and Samuels 1994). PCR products were sequenced and submitted to GenBank with the following accession numbers OQ130480 (ITS), OQ190093 (TUB2), OQ190092 (RPB2), and OQ255570 (LSU). BLASTn search revealed that the ITS, TUB2, RPB2, and LSU gene sequences of isolate Z5 showed 99.42% (513/516 bp), 99.69% (320/321 bp), 100% (1071/1071 bp), and 100% (857/857 bp) identity with those of ex-type S. pogostemonis stain ZHKUCC 21-0001 (Dong et al. 2021), respectively. A phylogenetic tree was constructed showing that Z5 clustered with S. pogostemonis (Figure 2). The isolates in this study were identified as S. pogostemonis based on morphological and molecular evidence. To confirm pathogenicity, five one-month-old 'Ningyu' cultivar strawberry seedlings were planted in sterilized nursery soil mixed with wheat grains (0.5% w/w) coated with Z5 mycelia (Fang 2007). An equal number of strawberry seedlings were placed in pots filled with non-infected potting mix to serve as controls. The seedlings were kept in a greenhouse under a 12 h light/dark photoperiod at 25°C. After two weeks, the inoculated seedlings displayed symptoms such as leaf wilting and root necrosis, similar to those observed in the greenhouses, while the control seedlings showed no symptoms (Figures 1f, 1g). The experiment was performed thrice. The identical fungus was re-isolated from the symptomatic roots and identified as S. pogostemonis based on morphological characteristics and molecular analysis, thus fulfilling Koch's postulates. This is the first report of S. pogostemonis causing root rot on strawberries worldwide. Our findings will contribute to a more comprehensive study on investigating and managing this disease.

2.
J Transl Med ; 21(1): 596, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37670338

RESUMEN

BACKGROUND: Ovarian cancer (OC) is a highly aggressive gynecological malignancy prevalent worldwide. Most OC cases are typically diagnosed at advanced stages, which has led to a 5-year overall survival rate of less than 35% following conventional treatment. Furthermore, immune checkpoint inhibitor therapy has shown limited efficacy in the treatment of patients with OC, and CAR-T therapy has also demonstrated modest results owing to inadequate T cell infiltration. Therefore, novel strategies must be developed to enhance T cell persistence and trafficking within the OC tumor microenvironment. METHODS: In this study, we developed a novel adoptive T-cell therapy for ovarian cancer based on a chimeric antigen receptor structure. We used a ligand-receptor binding motif to enhance the therapeutic effect of targeting CA125. Since mesothelin can naturally bind to CA125 with high affinity, we concatenated the core-binding fragment of mesothelin with the 4-1BB and CD3ζ signal fragments to assemble a novel CA125-targeting chimeric receptor (CR). The CAR structure targeting CA125 derived from the 4H11 antibody was also constructed. CR- and CAR-encoding RNA were electroporated into T cells to evaluate their antitumor activity both in vitro and in vivo. RESULTS: While CR-T or CAR-T cells exhibited moderate activity against two ovarian cancer cell lines, T cells co-expressing CR and CAR exhibited a superior killing effect compared to T cells expressing either CR or CAR alone. Furthermore, upon interaction with ovarian tumors, the ability of CR and CAR T cells to release activation markers and functional cytokines increased significantly. Similarly, CR and CAR co-expressing T cells persistently controlled the growth of transplanted ovarian cancer tumors in NSG mice and significantly prolonged the overall survival of tumor-challenged mice. Transcriptome sequencing revealed that the survival and cytotoxicity of T cells co-expressing CR and CAR were significantly altered compared with those of T cells expressing either CR or CAR. CONCLUSION: Our findings demonstrate that CA125 targeting CR and CAR can synergistically kill ovarian cancer cells, indicating that CA125 targeting by the two binding motifs simultaneously in tumors may improve the therapeutic outcomes of ovarian cancer treatment.


Asunto(s)
Neoplasias Ováricas , Receptores Quiméricos de Antígenos , Animales , Ratones , Femenino , Humanos , Mesotelina , Ligandos , Linfocitos T , Antígeno Ca-125 , Microambiente Tumoral
3.
BMC Musculoskelet Disord ; 24(1): 782, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37789309

RESUMEN

OBJECTIVE: To determine whether superoxide dismutase (SOD) and glutathione reductase (GR) correlated with the intervertebral disc degeneration (IDD) severity and the postoperative spinal fusion rate in lumbar spinal stenosis patients accompanied with lumbar disc herniation. METHODS: This retrospective study investigated 310 cases of posterior lumbar decompression and fusion. The cumulative grade was calculated by adding the pfirrmann grades of all the lumbar discs. Subjects were grouped based on the median cumulative grade. Logistic regression was used to determine the associations among the demographical, clinical, and laboratory indexes and severe degeneration and fusion. The receiver operating characteristic (ROC) curve was performed to measure model discrimination, and Hosmer-Lemeshow (H-L) test was used to measure calibration. RESULTS: SOD and GR levels were significantly lower in the severe degeneration group (cumulative grade > 18) than in the mild to moderate degeneration group (cumulative grade ≤ 18). Furthermore, the SOD and GR concentrations of the fusion group were significantly higher than that of the non-fusion group (p < 0.001 and p = 0.006). The multivariate binary logistic models revealed that SOD and GR were independently influencing factors of the severe degeneration (OR: 0.966, 95%CI: 0.950-0.982, and OR: 0.946, 95%CI: 0.915-0.978, respectively) and non-fusion (OR: 0.962; 95% CI: 0.947-0.978; OR: 0.963; 95% CI: 0.933-0.994). The models showed excellent discrimination and calibration. Trend analysis indicated that the levels of SOD and GR tended to decrease with increasing severity (p for trend < 0.001 and 0.003). In addition, it also revealed that SOD provided protection from non-fusion in a concentration-dependent manner (p for trend < 0.001). However, GR concentration-dependent effects were not apparent (p for trend = 0.301). CONCLUSION: High serum SOD and GR levels are associated with a better fusion prognosis and a relief in degeneration severity.


Asunto(s)
Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral , Disco Intervertebral , Fusión Vertebral , Estenosis Espinal , Humanos , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/cirugía , Estenosis Espinal/cirugía , Antioxidantes , Estudios Retrospectivos , Vértebras Lumbares/cirugía , Degeneración del Disco Intervertebral/cirugía , Superóxido Dismutasa
4.
Sensors (Basel) ; 23(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37896670

RESUMEN

This paper reports a method for calculating the electromagnetic force acting on an aluminum honeycomb sandwich panel moving in a magnetic field. This research is motivated by the non-contact electromagnetic detumbling technology for space non-cooperative targets. Past modeling of the electromagnetic forces and torques generally assumes that the target is homogeneous. However, aluminum honeycomb sandwich panels are extensively used in spacecraft structures to reduce weight without sacrificing structural strength and stiffness, which are so inhomogeneous and complicated that it is difficult to obtain the induced electromagnetic force even by numerical methods. An equivalent conductivity tensor of an aluminum honeycomb sandwich panel is proposed, which allows the aluminum honeycomb sandwich panel to be treated as a homogeneous structure when calculating the induced electromagnetic forces. The advantage of the equivalent conductivity tensor in the calculation of induced electromagnetic forces is verified by finite element simulations. The proposed method makes it possible to evaluate the electromagnetic force of a large aluminum honeycomb sandwich structure moving in a magnetic field.

5.
Mol Breed ; 42(6): 30, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37312963

RESUMEN

The combination of molecular markers and phenotypes to select superior parents has become the goal of modern breeders. In this study, 491 upland cotton (Gossypium hirsutum L.) accessions were genotyped using the CottonSNP80K array and then a core collection (CC) was constructed. Superior parents with high fiber quality were identified using molecular markers and phenotypes based on the CC. The Nei diversity index, Shannon's diversity index, and polymorphism information content among chromosomes for 491 accessions ranged from 0.307 to 0.402, 0.467 to 0.587, and 0.246 to 0.316, with mean values of 0.365, 0.542, and 0.291, respectively. A CC containing 122 accessions was established and was categorized into eight clusters based on the K2P genetic distances. From the CC, 36 superior parents (including duplicates) were selected, which contained the elite alleles of markers and ranked in the top 10% of phenotypic values for each fiber quality trait. Among the 36 materials, eight were for fiber length, four were for fiber strength, nine were for fiber micronaire, five were for fiber uniformity, and ten were for fiber elongation. In particular, the nine materials, 348 (Xinluzhong34), 319 (Xinluzhong3), 325 (Xinluzhong9), 397 (L1-14), 205 (XianIII9704), 258 (9D208), 464 (DP201), 467 (DP150), and 465 (DP208), possessed the elite alleles of markers for at least two traits and could be given priority in breeding applications for a more synchronous improvement of fiber quality. The work provides an efficient method for superior parent selection and will facilitate the application of molecular design breeding to cotton fiber quality. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01300-0.

6.
Development ; 145(24)2018 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-30470705

RESUMEN

Krüppel-homolog 1 (Kr-h1), a zinc-finger transcription factor, inhibits larval metamorphosis and promotes adult reproduction by transducing juvenile hormone (JH). Although the transcriptional regulation of Kr-h1 has been extensively studied, little is known about its regulation at the post-transcriptional level. Using the migratory locust Locusta migratoria as a model system, we report here that the microRNAs let-7 and miR-278 bound to the Kr-h1 coding sequence and downregulated its expression. Application of let-7 and miR-278 mimics (agomiRs) significantly reduced the level of Kr-h1 transcripts, resulting in partially precocious metamorphosis in nymphs as well as markedly decreased yolk protein precursors, arrested ovarian development and blocked oocyte maturation in adults. Moreover, the expression of let-7 and miR-278 was repressed by JH, constituting a regulatory loop of JH signaling. This study thus reveals a previously unknown regulatory mechanism whereby JH suppresses the expression of let-7 and miR-278, which, together with JH induction of Kr-h1 transcription, prevents the precocious metamorphosis of nymphs and stimulates the reproduction of adult females. These results advance our understanding of the coordination of JH and miRNA regulation in insect development.


Asunto(s)
Genes de Insecto , Saltamontes/crecimiento & desarrollo , Saltamontes/genética , Hormonas Juveniles/farmacología , Factores de Transcripción de Tipo Kruppel/genética , Metamorfosis Biológica/genética , MicroARNs/metabolismo , Oogénesis/genética , Animales , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Saltamontes/efectos de los fármacos , Factores de Transcripción de Tipo Kruppel/metabolismo , Metamorfosis Biológica/efectos de los fármacos , MicroARNs/genética , Oocitos/metabolismo , Oogénesis/efectos de los fármacos , Óvulo/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo , Vitelogénesis/efectos de los fármacos , Vitelogénesis/genética
7.
BMC Plant Biol ; 21(1): 588, 2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34895144

RESUMEN

BACKGROUND: Frogeye leaf spot (FLS) is a destructive fungal disease that affects soybean production. The most economical and effective strategy to control FLS is the use of resistant cultivars. However, the use of a limited number of resistant loci in FLS management will be countered by the emergence of new high-virulence Cercospora sojina races. Therefore, we identified quantitative trait loci (QTL) that control resistance to FLS and identified novel resistant genes using a genome-wide association study (GWAS) on 234 Chinese soybean cultivars. RESULTS: A total of 30,890 single nucleotide polymorphism (SNP) markers were used to estimate linkage disequilibrium (LD) and population structure. The GWAS results showed four loci (p < 0.0001) distributed over chromosomes (Chr.) 5 and 20, that are significantly associated with FLS resistance. No previous studies have reported resistance loci in these regions. Subsequently, 45 genes in the two resistance-related haplotype blocks were annotated. Among them, Glyma20g31630 encoding pyruvate dehydrogenase (PDH), Glyma05g28980, which encodes mitogen-activated protein kinase 7 (MPK7), and Glyma20g31510, Glyma20g31520 encoding calcium-dependent protein kinase 4 (CDPK4) in the haplotype blocks deserves special attention. CONCLUSIONS: This study showed that GWAS can be employed as an effective strategy for identifying disease resistance traits in soybean and narrowing SNPs and candidate genes. The prediction of candidate genes in the haplotype blocks identified by disease resistance loci can provide a useful reference to study systemic disease resistance.


Asunto(s)
Cercospora/patogenicidad , Resistencia a la Enfermedad/genética , Glycine max/genética , Enfermedades de las Plantas/inmunología , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos , Modelos Lineales , Desequilibrio de Ligamiento , Fenotipo , Enfermedades de las Plantas/microbiología , Glycine max/inmunología , Glycine max/microbiología , Virulencia
8.
BMC Plant Biol ; 20(1): 127, 2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32216758

RESUMEN

BACKGROUND: Soybean developing seed is susceptible to high temperature and humidity (HTH) stress in the field, resulting in vigor reduction. Actually, the HTH in the field during soybean seed growth and development would also stress the whole plant, especially on leaf and pod, which in turn affect seed growth and development as well as vigor formation through nutrient supply and protection. RESULTS: In the present study, using a pair of pre-harvest seed deterioration-sensitive and -resistant cultivars Ningzhen No. 1 and Xiangdou No. 3, the comprehensive effects of HTH stress on seed vigor formation during physiological maturity were investigated by analyzing cotyledon, embryo, leaf, and pod at the levels of protein, ultrastructure, and physiology and biochemistry. There were 247, 179, and 517 differentially abundant proteins (DAPs) identified in cotyledon, embryo, and leaf of cv. Xiangdou No. 3 under HTH stress, while 235, 366, and 479 DAPs were identified in cotyledon, embryo, and leaf of cv. Ningzhen No. 1. Moreover, 120, 144, and 438 DAPs between the two cultivars were identified in cotyledon, embryo, and leaf under HTH stress, respectively. Moreover, 120, 144, and 438 DAPs between the two cultivars were identified in cotyledon, embryo, and leaf under HTH stress, respectively. Most of the DAPs identified were found to be involved in major metabolic pathways and cellular processes, including signal transduction, tricarboxylic acid cycle, fatty acid metabolism, photosynthesis, protein processing, folding and assembly, protein biosynthesis or degradation, plant-pathogen interaction, starch and sucrose metabolism, and oxidative stress response. The HTH stress had less negative effects on metabolic pathways, cell ultrastructure, and physiology and biochemistry in the four organs of Xiangdou No. 3 than in those of Ningzhen No. 1, leading to produce higher vigor seeds in the former. CONCLUSION: High seed vigor formation is enhanced by increasing protein biosynthesis and nutrient storage in cotyledon, stronger stability and viability in embryo, more powerful photosynthetic capacity and nutrient supply in leaf, and stronger protection in pod under HTH stress. These results provide comprehensive characteristics of leaf, pod and seed (cotyledon and embryo) under HTH stress, and some of them can be used as selection index in high seed vigor breeding program in soybean.


Asunto(s)
Cotiledón/fisiología , Glycine max/fisiología , Calor , Humedad , Hojas de la Planta/fisiología , Semillas/fisiología , Cotiledón/química , Hojas de la Planta/química , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Semillas/química , Semillas/crecimiento & desarrollo , Glycine max/química
9.
BMC Microbiol ; 20(1): 166, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32546122

RESUMEN

BACKGROUND: Cercospora sojina is a fungal pathogen that causes frogeye leaf spot in soybean-producing regions, leading to severe yield losses worldwide. It exhibits variations in virulence due to race differentiation between strains. However, the candidate virulence-related genes are unknown because the infection process is slow, making it difficult to collect transcriptome samples. RESULTS: In this study, virulence-related differentially expressed genes (DEGs) were obtained from the highly virulent Race 15 strain and mildly virulent Race1 strain under nitrogen starvation stress, which mimics the physiology of the pathogen during infection. Weighted gene co-expression network analysis (WGCNA) was then used to find co-expressed gene modules and assess the relationship between gene networks and phenotypes. Upon comparison of the transcriptomic differences in virulence between the strains, a total of 378 and 124 DEGs were upregulated, while 294 and 220 were downregulated in Race 1 and Race 15, respectively. Annotation of these DEGs revealed that many were associated with virulence differences, including scytalone dehydratase, 1,3,8-trihydroxynaphthalene reductase, and ß-1,3-glucanase. In addition, two modules highly correlated with the highly virulent strain Race 15 and 36 virulence-related DEGs were found to contain mostly ß-1,4-glucanase, ß-1,4-xylanas, and cellobiose dehydrogenase. CONCLUSIONS: These important nitrogen starvation-responsive DEGs are frequently involved in the synthesis of melanin, polyphosphate storage in the vacuole, lignocellulose degradation, and cellulose degradation during fungal development and differentiation. Transcriptome analysis indicated unique gene expression patterns, providing further insight into pathogenesis.


Asunto(s)
Cercospora/patogenicidad , Perfilación de la Expresión Génica/métodos , Nitrógeno/metabolismo , Factores de Virulencia/genética , Cercospora/clasificación , Cercospora/genética , Cercospora/metabolismo , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Redes Reguladoras de Genes , Anotación de Secuencia Molecular , Fenotipo , Análisis de Secuencia de ARN , Glycine max/microbiología , Especificidad de la Especie , Estrés Fisiológico
10.
Sensors (Basel) ; 20(13)2020 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-32635575

RESUMEN

The autonomous underwater glider has attracted enormous interest for underwater activities, especially in long-term and large-scale underwater data collection. In this paper, we focus on the application of gliders gathering data from underwater sensor networks over underwater acoustic channels. However, this application suffers from a rapidly time-varying environment and limited energy. To optimize the performance of data collection and maximize the network lifetime, we propose a distributed, energy-efficient sensor scheduling algorithm based on the multi-armed bandit formulation. Besides, we design an indexable threshold policy to tradeoff between the data quality and the collection delay. Moreover, to reduce the computational complexity, we divide the proposed algorithm into off-line computation and on-line scheduling parts. Simulation results indicate that the proposed policy significantly improves the performance of the data collection and reduces the energy consumption. They prove the effectiveness of the threshold, which could reduce the collection delay by at least 10% while guaranteeing the data quality.

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