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1.
J Sci Food Agric ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38877787

RESUMEN

BACKGROUND: With the rapid development of deep learning, the recognition of rice disease images using deep neural networks has become a hot research topic. However, most previous studies only focus on the modification of deep learning models, while lacking research to systematically and scientifically explore the impact of different data sizes on the image recognition task for rice diseases. In this study, a functional model was developed to predict the relationship between the size of dataset and the accuracy rate of model recognition. RESULTS: Training VGG16 deep learning models with different quantities of images of rice blast-diseased leaves and healthy rice leaves, it was found that the test accuracy of the resulting models could be well fitted with an exponential model (A = 0.9965 - e(-0.0603×I50-1.6693)). Experimental results showed that with an increase of image quantity, the recognition accuracy of deep learning models would show a rapid increase at first. Yet when the image quantity increases beyond a certain threshold, the accuracy of image classification would not improve much, and the marginal benefit would be reduced. This trend remained similar when the composition of the dataset was changed, no matter whether (i) the disease class was changed, (ii) the number of classes was increased or (iii) the image data were augmented. CONCLUSIONS: This study provided a scientific basis for the impact of data size on the accuracy of rice disease image recognition, and may also serve as a reference for researchers for database construction. © 2024 Society of Chemical Industry.

2.
Proc Natl Acad Sci U S A ; 121(19): e2402045121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38683998

RESUMEN

Phytophagous insects have evolved sophisticated detoxification systems to overcome the antiherbivore chemical defenses produced by many plants. However, how these biotransformation systems differ in generalist and specialist insect species and their role in determining insect host plant range remains an open question. Here, we show that UDP-glucosyltransferases (UGTs) play a key role in determining the host range of insect species within the Spodoptera genus. Comparative genomic analyses of Spodoptera species that differ in host plant breadth identified a relatively conserved number of UGT genes in generalist species but high levels of UGT gene pseudogenization in the specialist Spodoptera picta. CRISPR-Cas9 knockouts of the three main UGT gene clusters of Spodoptera frugiperda revealed that UGT33 genes play an important role in allowing this species to utilize the poaceous plants maize, wheat, and rice, while UGT40 genes facilitate utilization of cotton. Further functional analyses in vivo and in vitro identified the UGT SfUGT33F32 as the key mechanism that allows generalist S. frugiperda to detoxify the benzoxazinoid DIMBOA (2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), a potent insecticidal phytotoxin produced by poaceous plants. However, while this detoxification capacity is conserved in several generalist Spodoptera species, Spodoptera picta, which specializes on Crinum plants, is unable to detoxify DIMBOA due to a nonfunctionalizing mutation in SpUGT33F34. Collectively, these findings provide insight into the role of insect UGTs in host plant adaptation, the mechanistic basis of evolutionary transitions between generalism and specialism and offer molecular targets for controlling a group of notorious insect pests.


Asunto(s)
Spodoptera , Animales , Spodoptera/genética , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Especificidad del Huésped/genética , Uridina Difosfato/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Filogenia
3.
J Trop Med ; 2022: 5236430, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36211624

RESUMEN

Objective: The main aim of this study was to determine the prevalence, capsular genotyping, antimicrobial susceptibility, and associated factors of colonizing Group B Streptococcus (GBS) in pregnant women admitted to a hospital in Jinan, East China. Methods: Demographic data, clinical characteristics, and vaginal and rectal swabs were obtained from a group of expecting mothers subjected to GBS screening at the late stage of pregnancy who went into labor over the period from November 2019 to October 2020. Identification of GBS and determination of antimicrobial resistance patterns were performed using a BD Phoenix-100 system. Capsular genotypes were analyzed using polymerase chain reaction and the associated factors were evaluated via logistic regression. Result: A total of 2761 pregnant women were recruited for this study. The GBS colonization rate was 6.70% (185/2761). Among the 172 GBS strains examined, all were susceptible to vancomycin and linezolid. Resistance was the highest for erythromycin (80.2%), followed by clindamycin (75.0%), levofloxacin (65.1%), and tetracycline (57.6%). The most common serotype identified was Ia (61.0%), followed by III (29.7%), VI (4.6%), II (3.5%), VII (0.6%), and a nontypeable strain. Risk factors for maternal GBS colonization included maternal age (older than 30 years) (OR = 1.913 (1.662, 2.478)), gestational age at birth (average gestational age) (OR = 1.992 (1.445, 2.746)), and prelabor rupture of membrane (OR = 3.838 (1.619, 9.099)). Conclusion: The prevalence of GBS was relatively low. The maternal age was a factor associated with GBS colonization. Subjects showing GBS positivity during late pregnancy were prone to prolonged rupture of the membrane (PROM) and birth at lower a gestation age than the GBS-negative group. Penicillin could still be used as the first agent of choice for intrapartum antibiotic prophylaxis (IAP).

4.
Front Plant Sci ; 13: 910878, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35865283

RESUMEN

In recent years, the convolution neural network has been the most widely used deep learning algorithm in the field of plant disease diagnosis and has performed well in classification. However, in practice, there are still some specific issues that have not been paid adequate attention to. For instance, the same pathogen may cause similar or different symptoms when infecting plant leaves, while the same pathogen may cause similar or disparate symptoms on different parts of the plant. Therefore, questions come up naturally: should the images showing different symptoms of the same disease be in one class or two separate classes in the image database? Also, how will the different classification methods affect the results of image recognition? In this study, taking rice leaf blast and neck blast caused by Magnaporthe oryzae, and rice sheath blight caused by Rhizoctonia solani as examples, three experiments were designed to explore how database configuration affects recognition accuracy in recognizing different symptoms of the same disease on the same plant part, similar symptoms of the same disease on different parts, and different symptoms on different parts. The results suggested that when the symptoms of the same disease were the same or similar, no matter whether they were on the same plant part or not, training combined classes of these images can get better performance than training them separately. When the difference between symptoms was obvious, the classification was relatively easy, and both separate training and combined training could achieve relatively high recognition accuracy. The results also, to a certain extent, indicated that the greater the number of images in the training data set, the higher the average classification accuracy.

5.
Neuroscience ; 398: 252-262, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30553789

RESUMEN

Our previous study showed that acid-sensing ion channel 3 (ASIC3) in the trigeminal nucleus caudalis (TNC) is involved in the pathogenesis of recurrent migraine. ASIC3 is regulated by nerve growth factor (NGF), which induces hyperalgesia in various pain disorders. Neutralization of NGF is considered an effective treatment method. However, the contribution of NGF to repeated migraine-like attacks in chronic migraine (CM) remains unclear. Therefore, this study investigated the effect of NGF on ASIC3 expression in the TNC and the role of NGF signaling in chemical dural stimulation-induced hyperalgesia. A rat model was established by repeated dural infusions of inflammatory soup (IS) for seven days to simulate CM attacks. After repeated IS infusions, cutaneous hyperalgesia appeared in the rats' periorbital region and hind paws, which showed significantly lower pain thresholds. IS infusions upregulated the mRNA and protein of NGF in the TNC, and NGF was mainly expressed in the cytoplasm of TNC neurons. An intracerebroventricular injection of an anti-NGF-neutralizing antibody relieved the cutaneous hyperalgesia of CM rats and decreased protein kinase C (PKC), ASIC3, calcitonin gene-related peptide (CGRP) and c-Fos expression in the TNC. Moreover, intracerebroventricular injection with the PKC blocker chelerythrine chloride alleviated IS infusion-induced hyperalgesia and reduced ASIC3, CGRP and c-Fos levels in the TNC. These results indicate that NGF might regulate ASIC3 expression via PKC activity in the TNC following repeated IS dural stimulation, and this signaling pathway might participate in IS-induced hyperalgesia.


Asunto(s)
Hiperalgesia/metabolismo , Trastornos Migrañosos/metabolismo , Factor de Crecimiento Nervioso/antagonistas & inhibidores , Factor de Crecimiento Nervioso/metabolismo , Núcleos del Trigémino/metabolismo , Canales Iónicos Sensibles al Ácido/metabolismo , Analgésicos/farmacología , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Modelos Animales de Enfermedad , Hiperalgesia/patología , Hiperalgesia/terapia , Inflamación/metabolismo , Inflamación/patología , Inflamación/terapia , Masculino , Trastornos Migrañosos/patología , Trastornos Migrañosos/terapia , Proteína Quinasa C/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Distribución Aleatoria , Ratas Sprague-Dawley , Fenómenos Fisiológicos de la Piel , Núcleos del Trigémino/patología
6.
J Headache Pain ; 19(1): 102, 2018 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-30400767

RESUMEN

BACKGROUND: Although the mechanism of chronic migraine (CM) is unclear, it might be related to central sensitization and neuronal persistent hyperexcitability. The tyrosine phosphorylation of NR2B (NR2B-pTyr) reportedly contributes to the development of central sensitization and persistent pain in the spinal cord. Central sensitization is thought to be associated with an increase in synaptic efficiency, but the mechanism through which NR2B-pTyr regulates synaptic participation in CM-related central sensitization is unknown. In this study, we aim to investigate the role of NR2B-pTyr in regulating synaptic plasticity in CM-related central sensitization. METHODS: Male Sprague-Dawley rats were subjected to seven inflammatory soup (IS) injections to model recurrent trigeminovascular or dural nociceptor activation, which is assumed to occur in patients with CM. We used the von Frey test to detect changes in mechanical withdrawal thresholds, and western blotting and immunofluorescence staining assays were performed to detect the expression of NR2B-pTyr in the trigeminal nucleus caudalis (TNC). NR2B-pTyr was blocked with the Src family kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)-pyrazolo [3,4-d] pyrimidine (PP2) and the protein tyrosine kinase inhibitor genistein to detected the changes in calcitonin gene-related peptide (CGRP), substance P (SP), and the synaptic proteins postsynaptic density 95 (PSD95), synaptophysin (Syp), synaptotagmin1 (Syt-1). The synaptic ultrastructures were observed by transmission electron microscopy (TEM), and the dendritic architecture of TNC neurons was observed by Golgi-Cox staining. RESULTS: Statistical analyses revealed that repeated infusions of IS induced mechanical allodynia and significantly increased the expression of NR2B Tyr-1472 phosphorylation (pNR2B-Y1472) and NR2B Tyr-1252 phosphorylation (pNR2B-Y1252) in the TNC. Furthermore, the inhibition of NR2B-pTyr by PP2 and genistein relieved allodynia and reduced the expression of CGRP, SP, PSD95, Syp and Syt-1 and synaptic transmission. CONCLUSIONS: These data indicate that NR2B-pTyr might regulate synaptic plasticity in central sensitization in a CM rat model. The inhibition of NR2B tyrosine phosphorylation has a protective effect on threshold dysfunction and migraine attacks through the regulation of synaptic plasticity in central sensitization.


Asunto(s)
Sensibilización del Sistema Nervioso Central/fisiología , Modelos Animales de Enfermedad , Trastornos Migrañosos/metabolismo , Plasticidad Neuronal/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Tirosina/metabolismo , Animales , Hiperalgesia/metabolismo , Hiperalgesia/patología , Masculino , Trastornos Migrañosos/patología , Neuronas/metabolismo , Neuronas/patología , Dolor/metabolismo , Dolor/patología , Fosforilación/fisiología , Ratas , Ratas Sprague-Dawley , Núcleo Caudal del Trigémino/metabolismo , Núcleo Caudal del Trigémino/patología
7.
Open Life Sci ; 13: 112-118, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33817076

RESUMEN

Endoplasmic reticulum stress is one of the mechanisms of cell apoptosis. In this study, the mechanism of oxymatrine-induced human esophageal cancer Eca-109 cell apoptosis by the endoplasmic reticulum stress pathway was investigated. Eca-109 cells were cultured in vitro with different doses of oxymatrine (0.5, 1, 2 µg/mL) for 48 h. The cell viability and proliferation inhibition rate were examined by MTT assay and cell cycle assay. The apoptosis rate was examined by Annexin V-FITC/propidium iodide assay. The expression of endoplasmic reticulum stress markers, including binding immunoglobulin protein and CCAAT-enhancer-binding protein homologous protein, were determined by real-time quantitative polymerase chain reaction and western blotting, respectively. MTT data showed that oxymatrine significantly inhibited the proliferation of Eca-109 cells. The cell apoptosis rate was quantified by flow cytometry. The expression of binding immunoglobulin protein was markedly downregulated in oxymatrine-treated Eca-109 cells while that of CCAAT-enhancer-binding protein homologous protein was upregulated. Oxymatrine inhibited proliferation and induced apoptosis of human esophageal carcinoma Eca-109 cells. Thus, oxymatrine may be a potential agent for treating human esophageal cancer.

8.
Zhongguo Gu Shang ; 29(6): 502-4, 2016 Jun.
Artículo en Chino | MEDLINE | ID: mdl-27534078

RESUMEN

OBJECTIVE: To explore clinical efficacy of closed reduction and external fixation under local anesthesia for the treatment of high-risk elderly patients with intertrochanteric fracture. METHODS: From March 2013 to March 2015, 10 patients with intertrochanteric fractures treated with closing reduction and external fixator under local anesthesia were analyszed, including 4 males and 6 females, aged from 69 to 88 years old with an average of 75.2 years old. All fractures were caused by injury and classified to type I (5 cases), II (3 cases), and V (2 cases) according to Evans classification. According to American Society of Anesthesiologists (ASA), 6 cases were type III and 4 cases were type IV. Blood loss,operative time,hospital stays, postoperative complications, ambulation time and fracture healing time were observed, and Harris scoring were used to evaluate hip joint function. RESULTS: All patients were followed up from 3 to 23 months with an average of 13.1 months. One patient with chronic obstructive pulmonary disease died for non-operation reason at 4 months after operation, the other fractures were healed at stage I, the mean fracture healing time was 5.6 months. There were no coxa vara, lower limb venous thrombosis, loosen and remove of needle passage. The average operative time was 46 min, blood loss was (35.00 ± 8.46) ml without blood transfusion. One patient was occurred pulmonary infection and stent-tract infection on the 2 nd and 3 rd day after operation, and improved with active anti-infection and dressing change; the other patients gone to ground activity at 4.2 d after operation. The patients stayed hospital for 10.6 d on average. According to Harris scoring at final following-up, the total score was 83.42 ± 3.27, 3 cases obtained excellent results, 5 cases good and 1 case poor. CONCLUSION: Closed reduction and external fixation under local anesthesia in treating high-risk elderly patients with intertrochanteric fracture,which has advantages of shorter operative time, less blood loss, good recovery of postoperative function, is a safe, stable and economic method.


Asunto(s)
Fracturas Cerradas/cirugía , Fracturas de Cadera/cirugía , Anciano , Anciano de 80 o más Años , Anestesia Local , Clavos Ortopédicos , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas , Fijación Intramedular de Fracturas , Humanos , Masculino , Resultado del Tratamiento
9.
World J Microbiol Biotechnol ; 29(5): 855-63, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23271461

RESUMEN

Exploration of novel active anti-tumor compounds from marine microbes for pharmaceutical applications has been a continuously hot spot in natural product research. Bacterial growth and metabolites may greatly vary under different culture conditions. In this study, the effects of different culture conditions and medium components on the growth and bioactive metabolites of Serratia proteamacula 657, an anti-tumor bacterium found in our previous study, were investigated. The results showed that lower temperature, weak acidic condition and solid fermentation favored the bacterial growth and the production of active compounds. Four components in the culture medium, NaCl, peptone, yeast extract and MgSO4, were found important to the bacterial growth and active compounds production in medium optimization. Under the optimized condition of solid state fermentation at pH 6.0-7.0, 23-25 °C, with the MgSO4-free medium containing 10.0 g/L peptone, 1.0 g/L yeast extract and 19.45 g/L NaCl, the antitumor activity of S. proteamacula 657 and the yield of crude extracts increased about 15 times and 6 times than the sample obtained in the original liquid fermentation, respectively. The active components in the metabolites of S. proteamacula 657 were identified as a homolog of prodigiosin, a red bacterial pigment, based on the analysis of the NMR and GC-MS. The bacterium S. proteamacula 657, which is adapted to lower temperature, produced prodigiosin-like pigments with highly antitumor activity, suggesting the bacterium is a potential new source for prodigiosin production.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/metabolismo , Medios de Cultivo/metabolismo , Microbiología Industrial/métodos , Serratia/metabolismo , Medios de Cultivo/química , Fermentación , Concentración de Iones de Hidrógeno , Serratia/química , Serratia/crecimiento & desarrollo , Temperatura
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