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1.
Plant Dis ; 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36825319

RESUMEN

Corn (Zea mays L.) plays an important role in China's cash crops, not only as food, but a vital raw material for animal husbandry and industry (Li et al. 2022). Pratylenchus zeae is one of the most damaging root-lesion nematodes (RLN) that can result in decreased yield and quality of crops (Liu et al. 2017). In September 2020, five root/soil samples were collected from the rhizosphere of corn (cv. Zhengdan 958), which had weak growth and root brown lesions in Chenzhou Village, Taolin Town, Donghai County, Lianyungang City, Jiangsu Province of China. Nematodes were extracted from the collected samples using the modified Baermann funnel method (Hooper et al. 2005). RLN were found in all samples, an average of 46 RLN per gram of root and 138 RLN per 100 cm3 of soil. The obtained RLN females were sterilized with 0.3% streptomycin sulfate and then inoculated on each carrot disks individually to obtain the purified population. RLN were examined by morphological and molecular characteristics to confirm the species indentification. The main morphological measurements of adult (n = 15) included body length = 524.7 µm (mean) ± 15.1 (standard deviation) (range = 490.7 to 543.6 µm), stylet = 15.2 µm ± 0.8 (14.2 to 16.8 µm), tail length = 30.3 µm ± 2.5 (26.3 to 35.3 µm), a = 25.6 ± 1.3 (24.4 to 29.3), b = 5.3 ± 0.3 (4.7 to 5.8), c = 17.4 ± 1.4 (14.9 to 19.3), two annules on the lip region. No males were found in the specimens. The morphological characters of this population are consistent with the description of P. zeae (Castillo and Vovlas, 2007). Furthermore, DNA was extracted from individual nematodes. The primers of TW81/AB28 and D2A/D3B (Subbotin et al. 2006) were used to amplified the rDNA-ITS region and rDNA 28S D2-D3 region, respectively. The purified PCR products were ligated into One step ZTOPO-Blunt/TA vector and transformed to Escherichia coli strain DH5α, and then sequenced by Sunya Biotechnology Co., Ltd (Henan, China). The obtained seqences were submitted to NCBI. The rDNA-ITS sequences (669 bp, GenBank Accession No: OP456372 and OP466367) exhibited 95.0% to 97.1% of identity with P. zeae sequences (KU198980 and KU198975). The obtained D2-D3 region of the 28S rDNA sequences (782 bp, OP441397 and OP448675) exhibited 99.7% to 100% identity with P. zeae sequences (EU130893 and KY424269). Consequently, both morphological and molecular data confirmed the identity of P. zeae. To further confirm reproduction on corn, single corn seeds (cv. Zhengdan 958) were sown in eight 2-liter pots filled with 1.8-liter of sterilized soil in greenhouse at 28°C. About 15 days after sowing, each pot with one corn plant with the same growth status was selected to inoculate with 1,000 mixed stage nematodes of P. zeae , Eight pots of uninoculated corn plants were used as controls. After 60 days, the inoculated plants were harvested and brown lesions were observed on roots. No symptoms and nematodes was detected in the control. An average number of RLN per pot was 3,752 in soil and 1,183 in roots were extracted, the reproduction factor (final population/initial population) was 4.94, indicating that P. zeae infects and reproduces well on this corn cultivar. P. zeae has only been reported on corn in Guangxi Province, southern in China(Fang et al. 1994). To our knowledge, this is the fist report of P. zeae infecting corn in Jiangsu Province, eastern in China. As P. zeae can cause great damage to corn, necessary measures should be taken to prevent the spread of P. zeae to other areas.

2.
Int J Colorectal Dis ; 37(10): 2229-2236, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36171411

RESUMEN

PURPOSE: This meta-analysis aims to investigate the role of prophylactic clipping after endoscopic colorectal polypectomy or endoscopic mucosal resection (EMR) in prevention of delayed bleeding (DB) following polypectomy. METHODS: We searched the PubMed, Embase, and Cochrane Library databases for randomized controlled trials comparing the effect of prophylactic clipping versus no clipping on DB since inception to 22nd April 2022. We then performed a meta-analysis using a random-effects model. RESULTS: We included 8 studies with 5648 patients and 10,436 lesions. Prophylactic clipping did not reduce the overall risk of DB compared with no clipping (1.54% vs 2.05%; Log RR, -0.29; 95% confidence interval [CI], -0.59, 0.01; P = 0.06). In subgroup analyses, clipping significantly reduced DB rate in polyps ≥ 2 cm (Log RR, -0.63; 95% CI, -1.08, -0.18; P = 0.01), in non-pedunculated polyps (Log RR, -0.63; 95% CI, -1.01, -0.24; P = 0.00), and in large (≥ 2 cm) proximal polyps (Log RR, -0.81; 95% CI, -1.56, 0.05; P = 0.04), but not in polyps < 2 cm (Log RR, 0.01; 95% CI, -.40, 0.42; P = 0.95). CONCLUSION: Prophylactic clipping does not prevent post-polypectomy bleeding after all EMR and should not be performed as a routine practice. Although prophylactic clipping may reduce DB rate following resection of large proximal polyps and non-pedunculated polyps, more high-quality studies are needed to determine the effects of factors such as polyp location, polyp morphology, antithrombotic drug use and complete or partial closure on the effectiveness of prophylactic clipping.


Asunto(s)
Pólipos del Colon , Neoplasias Colorrectales , Resección Endoscópica de la Mucosa , Pólipos del Colon/patología , Pólipos del Colon/cirugía , Colonoscopía/efectos adversos , Neoplasias Colorrectales/cirugía , Fibrinolíticos , Humanos , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/prevención & control
3.
Plant Dis ; 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35451860

RESUMEN

Pratylenchus coffeae Filipjev & Schuurmans Stekhoven, 1941, is one of the most important root-lesion nematodes (RLN) parasitizing many agronomic and industrial crops (Wang et al. 2021). Corn (Zea mays L.) is one economically important crop in China, with 35 million hectares cultivated annually (Li et al. 2019). In July 2019, a survey of RLN was carried out in corn field planting with cultivar Heyu 187 in Chuanba village in Qitai County, Xinjiang Uygur Autonomous Region, China. Five root/soil samples were collected from poor growing plants with distinct brown lesions. Nematodes were extracted from the collected root/soil samples with the modified Baermann funnel method (Hooper et al. 2005). The average of 157 RLN per 100 cm3 of soil and 43 RLN per gram of fresh root were extracted. The obtained RLN were sterilized with 0.3% streptomycin sulfate and cultured on carrot disks at 25°C. Twenty petri dishes with carrot disks, each inoculated with one female. The morphological and molecular characteristics of RLN cultured on carrot disks were examined for species identification. Morphological measurements of adult females (n=15) included body length (range = 529.0 to 658.0 µm, mean = 571.0 µm), head with two lip annuli, stylet (15.5 to 17.0 µm, 16.0 µm), tail length (27.5 to 32.5 µm, 30.5 µm), a (23.8 to 32.9, 28.5), b (5.8 to 7.1, 6.5), c (16.5 to 23.4, 18.9), and V (76.6 to 83.1%, 80.8%). Morphological measurements of adult males (n=15) were body length (range = 479.5 to 568.0 µm, mean = 516.0 µm), head with two lip annuli, stylet (14.5 to 15.5 µm, 15.0 µm), tail length (24.0 to 29.0 µm, 26.0 µm), spicule length (16.4 to 19.0 µm, 17.5 µm), gubernaculum length (4.4 to 5.3 µm, 4.9 µm), a (29.2 to 32.5, 31.0), b (5.7 to 6.9, 6.2), and c (18.2 to 22.6, 19.8). The morphological characters of this population are consistent with the description of P. coffeae (Castillo and Vovlas, 2007). Nematode DNA was extracted from an individual female. The primers of D2A/D3B (5'-ACAAGTACCGTGAGGGAAAGTTG-3'/5'-TCGGAAGGAACCAGCTACTA-3') (Subbotin et al. 2006) and 18S/26S (5'-TTGATTACGTCCCTGCCCTTT-3' / 5'-TTTCACTCGCCGTTACTAAGG-3') (Vrain et al. 1992) were used to amplify the D2/D3 expansion region of the 28S rRNA gene and the rDNA internal transcribed spacer (ITS) region, respectively. The PCR products were purified and transformed to E. coli strain DH5α, and then sequenced by Sangon Biotech Co. Ltd. (Shanghai, China). The obtained sequences of the D2/D3 region (793 bp) and the ITS region (1,242 bp) were submitted to GenBank, and the accession numbers for D2/D3 region were OK103614 and OK103619 which had 98.6% and 100% identity with the reported P. coffeae sequences (KC490925); the two obtained ITS sequences accession numbers OK103603 and OK103613) had more than 99% identity with published P. coffeae sequences from GenBank (e.g., LC030410, LC030395, MH134508 and LC030380). Hence, both morphological and molecular data demonstrated the presence of P. coffeae. To further confirm reproduction on corn, the obtained RLN population was used to inoculate corn plants in 2-liter pots containing 1.8-liter sterilized and mixed soil with 2 pastoral soil: 1 substrate in greenhouse at 27°C. About 15 days after sowing, each pot with one corn plant (cv. Heyu 187) with the same growth status was selected to inoculate P. coffeae. Five small holes near the roots were made using a glass rod. Approximately 1,000 mixed stage nematodes of P. coffeae were then pipetted into the holes of each plant. Eight replications were performed. Eight additional pots of uninoculated corn plants were used as control. After 2 months, corn roots were washed and brown lesions were observed on roots. The average number of RLN/pot was approximately 5,030 in soil and 2,870 in roots, and each pot had an average of 7.9 reproduction factors (final population/initial population), indicating that this nematode population infects and reproduces well on this corn cultivar. No nematodes and symptoms was detected in the control pot. The nematode of P. coffeae has only been reported on corn in Guangdong, Liaoning, Shangdong and Henan Provinces in China (Liu et al. 1996; Liu et al. 2001; Xia et al. 2021). To our knowledge, this is the first report of P. coffeae infecting corn in Xinjiang Uygur Autonomous Region of China. Since RLN can cause considerable damage to corn, one of the most important food crops produced in China, strategic measures should be taken to prevent the spread of P. coffeae to other regions.

4.
Med Image Anal ; 95: 103206, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38776844

RESUMEN

The correct interpretation of breast density is important in the assessment of breast cancer risk. AI has been shown capable of accurately predicting breast density, however, due to the differences in imaging characteristics across mammography systems, models built using data from one system do not generalize well to other systems. Though federated learning (FL) has emerged as a way to improve the generalizability of AI without the need to share data, the best way to preserve features from all training data during FL is an active area of research. To explore FL methodology, the breast density classification FL challenge was hosted in partnership with the American College of Radiology, Harvard Medical Schools' Mass General Brigham, University of Colorado, NVIDIA, and the National Institutes of Health National Cancer Institute. Challenge participants were able to submit docker containers capable of implementing FL on three simulated medical facilities, each containing a unique large mammography dataset. The breast density FL challenge ran from June 15 to September 5, 2022, attracting seven finalists from around the world. The winning FL submission reached a linear kappa score of 0.653 on the challenge test data and 0.413 on an external testing dataset, scoring comparably to a model trained on the same data in a central location.


Asunto(s)
Algoritmos , Densidad de la Mama , Neoplasias de la Mama , Mamografía , Humanos , Femenino , Mamografía/métodos , Neoplasias de la Mama/diagnóstico por imagen , Aprendizaje Automático
5.
Planta ; 236(5): 1485-98, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22798060

RESUMEN

WRKY transcription factors are crucial regulatory components of plant responses to pathogen infection. In the present study, we report isolation and functional characterization of the pathogen-responsive rice WRKY30 gene, whose transcripts accumulate rapidly in response to salicylic acid (SA) and jasmonic acid (JA) treatment. Overexpression of WRKY30 in rice enhanced resistance to rice sheath blight fungus Rhizoctonia solani and blast fungus Magnaporthe grisea. The enhanced resistance in the transgenic lines overexpressing WRKY30 was associated with activated expression of JA synthesis-related genes LOX, AOS2 and pathogenesis-related (PR)3 and PR10, and increased endogenous JA accumulation under the challenge of fungal pathogens. WRKY30 was nuclear-localized and had transcriptional activation ability in yeast cells, supporting that it functions as a transcription factor. Together, our findings indicate that JA plays a crucial role in the WRKY30-mediated defense responses to fungal pathogens, and that the rice WRKY30 seems promising as an important candidate gene to improve disease resistance in rice.


Asunto(s)
Ciclopentanos/metabolismo , Regulación de la Expresión Génica de las Plantas , Oryza/metabolismo , Oryza/microbiología , Oxilipinas/metabolismo , Proteínas de Plantas/genética , Núcleo Celular/metabolismo , Ciclopentanos/farmacología , ADN Complementario , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Magnaporthe/patogenicidad , Oryza/efectos de los fármacos , Oryza/genética , Oxilipinas/farmacología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Rhizoctonia/patogenicidad , Ácido Salicílico/farmacología , Activación Transcripcional , Levaduras/genética
6.
Microsc Microanal ; 16(4): 488-501, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20598200

RESUMEN

Multispectral analysis combined with the Periodic Acid-Schiff method was used to investigate cytological features of insoluble polysaccharides and changes in total insoluble polysaccharide content (TPC) during pollen development in rice, including four cytoplasmic male sterility lines (MSLs) and their corresponding fertility-maintaining lines (FMLs). The multispectral curves of the relative transmittance value (RTV) and the images of developing pollen cells were obtained across a range of successive wavelengths (400-720 nm). A minimum RTV was found near 550 nm indicating an absorption peak of the TPC. Thus, the TPC was measured using the RTV of 550 nm. In the four FMLs, the minimum TPC of developing pollen cells occurred at the late microspore stage, while the maximum TPC occurred at the mature pollen grain stage. The TPC levels of pollen cells were significantly higher in the four FMLs than in their corresponding MSLs during and after pollen abortion. Notably, a steep decrease of multispectral curves at 420 nm appeared before the occurrence of abortion, implying a marker associated with pollen abortion in rice. Our results will be helpful for exploring the changes in TPC during pollen ontogenesis in rice and provide a novel method for the study of bio-macromolecules.


Asunto(s)
Oryza/citología , Oryza/crecimiento & desarrollo , Polen/citología , Polen/crecimiento & desarrollo , Polisacáridos/análisis , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Confocal/métodos , Oryza/química , Polen/química
7.
Drug Saf Case Rep ; 5(1): 28, 2018 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-30470925

RESUMEN

An 85-year-old man was admitted to our hospital because of dysphagia, and was diagnosed with benign stricture of the esophagus. He was hospitalized repeatedly for balloon dilations. Pantoprazole sodium (80 mg, twice daily, intravenously) was administered each time when he was in hospital, while esomeprazole (20 mg/day, orally) was administered intermittently when he was at home. Reductions in both white blood cells and platelets were noticed about 4 months after proton pump inhibitors were introduced. Bone marrow suppression induced by proton pump inhibitors was diagnosed as proven by bone marrow biopsy. White blood cell, neutrophil, and platelet counts went back to the normal range after proton pump inhibitors were stopped. The present case shows a rare bi-cytopenia associated with proton pump inhibitors and suggests the importance of awareness of hematological adverse events during proton pump inhibitor therapy.

8.
Front Pharmacol ; 7: 489, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28018225

RESUMEN

Background: Acute pancreatitis is the most common serious complication of endoscopic retrograde cholangiopancreatography (ERCP). Although, somatostatin (SOM) has been used in the prevention of post-ERCP pancreatitis (PEP), the efficacy of SOM remains inconsistent. Methods: Electronic databases, including PubMed/MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), and the Science Citation Index were searched to retrieve relevant studies. Details of the study population, including patients' characteristics, sample size, regimen of drug administration and incidence of PEP, hyperamylasemia and abdominal pain were extracted by two investigators. Data were analyzed with Review Manager 5.3 software. Results: Eleven randomized controlled trials, enrolling a total of 4192 patients, were included in the meta-analysis. After data were pooled, we observed decreased incidence of ERCP-induced outcomes, such as PEP (RR = 0.63, 95% CI: 0.40, 0.98; P = 0.04) and hyperamylasemia (RR = 0.75, 95% CI: 0.66, 0.84; P < 0.001) in patients treated with SOM than those with placebo. Subgroup analysis by ethnicity found decreased incidence of PEP and hyperamylasemia in Asia only. Subgroup analysis by treatment schedule and dosage revealed decreased incidence of PEP and hyperamylasemia when SOM were treated with a single bolus or long-term infusion, or at dose above 3000 µg. We did not observed efficacy of SOM on abdominal pain in pooled or subgroup analysis. Conclusion: This meta-analysis of patients undergoing ERCP showed reduced incidence of PEP and hyperamylasemia when SOM was administrated with single bolus, long-term infusion, or high dosage. More data are needed to confirm our findings.

9.
Microsc Res Tech ; 68(6): 335-46, 2005 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-16358284

RESUMEN

Cellular images obtained by light microscopy have been analyzed qualitatively, but there is still a lack of quantitative information about the variations in cellular metabolism of selective substances. A new approach using the multispectral imaging microscope (MIM) to observe rice (Oryza sativa L.) pollen grains is reported. A liquid crystal tunable filter device was used for wavelength selection from 400 to 720 nm and a cooled two-dimensional monochrome charge coupled device for image detection. Rice pollen were stained respectively by acetocarmine, Coomassie blue, or iodine potassium-iodine, and then imaged by MIM. The images were processed by the WuDa Image Analysis System 2003 (computer software), and the transmittance spectra for pollen grain images were obtained. The statistical analysis of the transmittance data showed that the macromolecular amount (nucleic acid, protein, starch) of male-sterile line (MSL) pollen grains was less than those of the fertility-maintaining line (FML). For instance there was a significantly lower nucleic acid content in the MSL than in the FML pollen. The results revealed that pollen abortion was directly related to the diminution of intracellular substances for metabolism. Consequently, we have established a quantitative criterion to determine pollen sterility. Comparing the spectra features of the FML with the MSL, we found that certain spectra features can be used to identify various types of abortion pollens and the deficient cytoplasm of male-sterile rice. Our experimental results offer the first quantitative understanding for evaluating cell morphological structure correlated with cellular physiological status.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Confocal , Microscopía de Polarización , Oryza/citología , Polen/citología , Microscopía Confocal/instrumentación , Microscopía de Polarización/instrumentación , Polen/genética
10.
Yi Chuan Xue Bao ; 29(8): 696-9, 2002.
Artículo en Zh | MEDLINE | ID: mdl-12200860

RESUMEN

Using two-dimensional gel electrophoresis (2D-PAGE), seven protein maps of leaf protein were obtained and analyzed. The results showed that the protein maps of four male sterile lines, Zidao male sterile line, Yebai male sterile line, Honglian male sterile line and Maxie male sterile line, were different from each other; The maps of Zidao male sterile line and maintainer of trefoil stage were similar and so did the maps of stooling stage; Either the sterile line map of two stages or the maintainer's was different. It can be deduced that the difference of maps of two stages might relate to male sterility of Zidao male sterile line.


Asunto(s)
Oryza/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/análisis , Cruzamientos Genéticos , Electroforesis en Gel Bidimensional , Fertilidad/genética , Oryza/genética , Oryza/crecimiento & desarrollo
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