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1.
J Orthop Res ; 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35384025

RESUMO

Serial examination and direct measurement of intracompartmental pressure (ICP) are suboptimal strategies for the detection of acute compartment syndrome (CS) because they are operator-dependent and yield information that only indirectly reflects intracompartmental muscle perfusion. As a result, instances of unnecessary fasciotomy and unrecognized CS are relatively common. Recently, near-infrared spectroscopy (NIRS)-based systems for compartment monitoring have generated interest as an adjunct tool. Under ideal conditions, NIRS directly measures the oxygenation of intracompartmental muscle (StO2 ), thereby obviating the challenges of interpreting equivocal clinical examination or ICP data. Despite these potential advantages, existing NIRS sensors are plagued by technical difficulties that limit clinical utility. Most of these limitations relate to their transcutaneous design that makes them susceptible to both interference from intervening skin/subcutaneous tissue, underlying hematoma, and instability of the skin-sensor interface. Here, we present a flexible, wireless, Bluetooth-enabled, percutaneously introducible intramuscular NIRS device that directly and continuously measures the StO2 of intracompartmental muscle. Proof of concept for this device is demonstrated in a swine lower extremity balloon compression model of acute CS, wherein we simultaneously track muscle oxygenation, ICP, and compartment perfusion pressure (PP). The observed StO2 decreased with increasing ICP and decreasing PP and then recovered following pressure reduction. The mean change in StO2 as the PP was decreased from baseline to 30 mmHg was -7.6%. The mean difference between baseline and nadir StO2 was -17.4%. Cross-correlations (absolute value) describing the correspondence between StO2 and ICP were >0.73. This novel intramuscular NIRS device identifies decreased muscle perfusion in the setting of evolving CS.

2.
Nat Prod Res ; : 1-5, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35045779

RESUMO

This study investigated the content and biological activity of three solvent extracts of Adonis ramosa Franch (AR), which contains 12 types of phytochemicals. The overall yield and total protein content of the aqueous extract were the highest, and it exhibited the highest hydroxyl and superoxide radical-scavenging abilities, copper chelating abilities, and cupric reducing antioxidant capacity. Ethanol extract had the highest total phenolic, flavonoid, and carbohydrate contents, and it showed the highest iron chelating activity, and HClO- and nitrite-scavenging abilities. Methanol AR extract contained the highest total steroid and tannin contents; it also demonstrated high radical- and reactive oxygen species-scavenging abilities and had the best ferric reducing antioxidant power, which allowed it to effectively prevent ß-carotene bleaching. Methanol extract also showed good stability and low toxicity. All tested solvent extracts of AR exhibited weak enzyme-inhibitory activities for four enzymes (α-glucosidase, α-amylase, acetylcholinesterase and butyrylcholinesterase). Overall, AR can serve as a natural antioxidant.

3.
J Reconstr Microsurg ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34553344

RESUMO

BACKGROUND: Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are limited to flaps which carry a cutaneous paddle. As such, this useful and reliable technology has not previously been applicable to muscle-only free flaps where other modalities with substantial limitations continue to be utilized. METHODS: We present the first NIRS probe which allows continuous monitoring of local tissue oxygen saturation (StO2) directly within the substance of muscle tissue. This probe is flexible, subcentimeter in scale, waterproof, biocompatible, and is fitted with resorbable barbs which facilitate temporary autostabilization followed by easy atraumatic removal. This novel device was compared with a ViOptix T.Ox monitor in a porcine rectus abdominus myocutaneous flap model of arterial and venous occlusions. During these experiments, the T.Ox device was affixed to the skin paddle, while the novel probe was within the muscle component of the same flap. RESULTS: The intramuscular NIRS device and skin-mounted ViOptix T.Ox devices produced very similar StO2 tracings throughout the vascular clamping events, with obvious and parallel changes occurring upon vascular clamping and release. The normalized cross-correlation at zero lag describing correspondence between the novel intramuscular NIRS and T.Ox devices was >0.99. CONCLUSION: This novel intramuscular NIRS probe offers continuous monitoring of oxygen saturation within muscle flaps. This experiment demonstrates the potential suitability of this intramuscular NIRS probe for the task of muscle-only free flap monitoring, where NIRS has not previously been applicable. Testing in the clinical environment is necessary to assess durability and reliability.

4.
Plant Dis ; 105(11): 3538-3544, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34096770

RESUMO

Pomegranate crown rot caused by Coniella granati is one of the most severe diseases of pomegranate. No fungicides have been registered for controlling this disease in China. Pyraclostrobin, belonging to strobilurin fungicides, has a broad spectrum of activity against many phytopathogens. In this study, based on the mycelial growth and conidial germination inhibition methods, we investigated the biological activity of pyraclostrobin against C. granati in the presence of 50 µg/ml of salicylhydroxamic acid using 80 isolates collected from different orchards in China from 2012 to 2018. The EC50 (50% effective concentration) values ranged from 0.040 to 0.613 µg/ml for mycelial growth and 0.013 to 0.110 µg/ml for conidium germination. Treated with pyraclostrobin, the hyphae morphology changed and conidial production of C. granati decreased significantly. The result of transmission electron microscope showed that treatment of pyraclostrobin could make the cell wall thinner and lead to ruptured cell membrane and formation of intracellular organelle autophagosomes. The pyraclostrobin showed good protective and curative activities against C. granati on detached pomegranate fruits. In field trials, pyraclostrobin showed excellent control efficacy against this disease, in which the treatment of 25% pyraclostrobin EC 1,000× provided 92.25 and 92.58% control efficacy in 2019 and 2020, respectively, significantly higher than that of other treatments. Therefore, pyraclostrobin could be a candidate fungicide for the control of pomegranate crown rot.


Assuntos
Romã (Fruta) , Ascomicetos , Frutas , Doenças das Plantas , Estrobilurinas/farmacologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-33628315

RESUMO

PURPOSE: To assess the preventive effects of acupuncture at back-shu and front-mu acupoints on rats with restraint water-immersion stress (RWIS)-induced gastric ulcer. METHODS: Thirty-six rats were randomly divided into four groups for 10 days of treatment as follows: the normal group received no treatment; the model group received RWIS-induced gastric ulcer; the omeprazole group was administered omeprazole orally every 2 days; and the electroacupuncture group received electroacupuncture at the RN12 and BL21 acupoints every 2 days. After 10 days of treatment, except for the normal group, all rats were induced with gastric ulcer by RWIS for 3 h. The ulcer index (UI), ulcer inhibition rate, and histopathological score were calculated. We determined the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in serum, and the activities of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), and glutathione peroxidase (GSH-Px) in serum and gastric tissues. Protein expression of MyD88, nuclear factor (NF)-κB (p65), and toll-like receptor (TLR) 4 was quantified in gastric tissues. RESULTS: The electroacupuncture and omeprazole groups were equivalent in terms of UI, ulcer inhibition rate, and histopathological score. The serum levels of TNF-α and IL-6 were significantly lower in the electroacupuncture group compared with the omeprazole group (P < 0.05). Compared with the model group, there were significant changes in the levels of NO, MPO, GSH-Px, and MDA in all other groups, while the expression of TLR4, MyD88, and NF-κB p65 in gastric tissue decreased significantly in the electroacupuncture group. The expression of TLR4 was substantially lower in the electroacupuncture group compared with the omeprazole group. CONCLUSION: Acupuncture at back-shu and front-mu acupoints played a role in preventing gastric ulcer by inhibiting extracellular signals, stimulating kinases in serum and gastric tissues, and activating the inhibition of the TLR4 signaling pathway.

6.
Plant Dis ; 105(10): 3208-3217, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33560887

RESUMO

New fungicides are tools to manage fungal diseases and overcome emerging resistance in fungal pathogens. In this study, a total of 121 Fusarium fujikuroi isolates were collected from various geographical regions of China and their sensitivity to a novel succinate dehydrogenase inhibitor (SDHI) fungicide 'pydiflumetofen' was evaluated. The 50% effective concentration (EC50) value of pydiflumetofen for mycelial growth suppression ranged from 0.0101 to 0.1012 µg/ml and for conidial germination inhibition ranged from 0.0051 to 0.1082 µg/ml. Pydiflumetofen-treated hyphae showed contortion and increased branching, cell membrane permeability, and glycerol content significantly. The result of electron microscope transmission indicated that pydiflumetofen damaged the mycelial cell wall and the cell membrane, and almost broke up the cells, which increased the intracellular plasma leakage. There was no cross-resistance between pydiflumetofen and the widely used fungicides such as carbendazim, prochloraz, and phenamacril. Pydiflumetofen was found safe to seeds and rice seedlings of four rice cultivars, used up to 400 µg/ml. Seed treatment significantly decreased the rate of diseased plants in the greenhouse as well as in field trials in 2017 and 2018. Pydiflumetofen showed superb results against the rice bakanae disease (RBD), when used at 10 or 20 g a.i./100 kg of treated seeds, providing over 90% control efficacy (the maximum control efficacy was up to 97%), which was significantly higher than that of 25% phenamacril (SC) at 10 g or carbendazim at 100 g. Pydiflumetofen is highly effective against F. fujikuroi growth and sporulation as well as RBD in the field.


Assuntos
Fungicidas Industriais , Oryza , Fungicidas Industriais/farmacologia , Fusarium , Pirazóis , Succinato Desidrogenase , Ácido Succínico
7.
Plant Dis ; 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33496606

RESUMO

Lavender (Lavandula angustifolia Mill) is an ornamental plant and worldwidely grown for its aromatic and pharmacological qualities. In June 2020, the symptoms of blackleg disease on lavender plants were observed, with more than 50% incidence in Chaohu city (117°38'19.12″N, 31°47'18.94″W) of Anhui Province, China. The disease symptoms progressed from stem wilt and necrosis to prolonged necrosis and bending of leaves, and all infected lavender plants died eventually. Ten necrotic stem lesions werecollectedfrom ten independent plants for the isolation of pathogen. All samples were washed in 70% ethanol for 1 minute, rinsed twice in sterile distilled water and placed on water agar (WA) plates containing 30 mg/liter of kanamycin. All 16 fungal isolates were transferred onto potato dextrose agar (PDA) and incubated at 26°C for 5 days, and all fungal colonies were isolated consistently, which produced redish-gray mycelium at 26°C with a 12-h photoperiod on PDA media. They developed black pycnidia with abundant hyaline, unicellular, oval shaped conidia (4.5 to 5.9 × 2.1 to 2.5 µm) after 14 days. DNA was extracted (10-day-old culture) using the Fungal DNA Mini Kit (Omega Bio-tek, China), according to the manufacturer's protocol. The internal transcribed spacer (ITS), beta-tubulin (ß-tub) and translation elongation factor 1-alpha (tef1-α) genes of three isolates were amplified using the primers: ITS1/ITS4 (White et al. 1990), Bt2a/Bt2b (Glass et al. 1995) and EF1-728F/EF1-986R (Carbone et al. 1999), respectively. The ITS(MT883331), ß-tub(MT896891) andtef1-α (MT874165) genes were sequenced and analyzed through BLASTn. The ITS sequence showed 99.81% with Epicoccum sorghinum (GenBank Accession No. MK020690.1). The ß-tub and tef1-α showed 100% homology with Epicoccum sorghinum (GenBank AccessionMN554062.1 and MN512426.1), respectively. To complete Koch's postulates, pathogenicity tests were performed by spraying the fungal spore suspension (1×105 CFU/ml) prepared from 14-day-old cultures onto needling wounded stems of 1-year-old potted healthy L. angustifolia plants. The healthy plants were sprayed with sterilized water onto needling wounded stems served as negative control. Wilting and stem necrosis were observed 5 days afterinoculation and incubation in a growth chamber at 26°C, with a 12-h photoperiod. All fungal infected plants died after 10 days, while, the control plants remained healthy. The fungus was re-isolated from the lesions of the inoculated plants and verified. Based on morphological characteristics, sequence analysis and pathogenicity test, the pathogen was identified as E. sorghinum. The pathogen has been observed previously on many plants such as tea (Bao et al. 2019) and taro (Liu et al. 2018), in China. To our knowledge, this is the first report of E. sorghinum causing blackleg disease of lavender in China and worldwide.

8.
Nat Prod Res ; 35(2): 346-349, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31177847

RESUMO

The aerial parts of Artemisia gmelinii Weber ex Stechm were collected from the northeast of China. The essential oil was obtained by hydrodistillation and analysed by GC-MS. A set of 66 compounds were identified representing 99.1% of the oil composition. The major compounds in the oil were cyclobutaneethanol, endo-borneol, germacrene D, eucalyptol, selin-6-en-4α-ol, bisabolone oxide A, caryophyllene and terpinen-4-ol. Moreover, the essential oil was evaluated for its antioxidant, antidiabetic, and anticholinesterase activities in vitro. Additionally, the antioxidant potential of the oil was evaluated using DPPH and ABTS assays. The oil showed good antidiabetic activity with an IC50 of 63.2 µg/mL, which was similar to that of the positive control acarbose, and weak anticholinesterase activities. These findings demonstrated that the essential oil of Artemisia gmelinii may be a good natural antidiabetic.


Assuntos
Artemisia/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Acetilcolinesterase/metabolismo , Antioxidantes/química , Butirilcolinesterase/metabolismo , China , Eucaliptol/análise , Cromatografia Gasosa-Espectrometria de Massas , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Componentes Aéreos da Planta/química , Sesquiterpenos Policíclicos/análise , Sesquiterpenos/análise , Sesquiterpenos/química , Sesquiterpenos de Germacrano/análise , Sesquiterpenos de Germacrano/química , Terpenos/análise
9.
Nat Prod Res ; 35(10): 1596-1604, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31204495

RESUMO

To find a potent α-glucosidase inhibitor, 24 tyrosol derivatives with different substituents located at the meta, ortho, or para position of the phenyl group have been synthesised via the Mitsunobu reaction, characterised by 1H NMR, 13C NMR, ESI-MS and IR and evaluated for inhibition. The derivatives possessed varying degrees of in vitro inhibitory activity against α-glucosidase and a relationship between the structure and activity was subsequently established for all compounds. Two of these compounds with substituents at the para position showed significant inhibitory effects surpassing that of the control standard acarbose. Molecular docking studies performed to better understand the binding interactions between the enzyme and the two most active compounds showed substantial binding within the active site of α-glucosidase. Taken together, these results indicate that the position of the substituent plays a crucial role in this inhibition and may facilitate the development of new α-glucosidase inhibitors.


Assuntos
Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Álcool Feniletílico/análogos & derivados , alfa-Glucosidases/metabolismo , Acarbose/química , Acarbose/farmacologia , Sítios de Ligação , Domínio Catalítico , Inibidores de Glicosídeo Hidrolases/química , Álcool Feniletílico/síntese química , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Relação Estrutura-Atividade , Leveduras/enzimologia , alfa-Glucosidases/química
10.
Nat Prod Res ; 35(21): 4084-4088, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31984779

RESUMO

We investigated the antioxidant activities of different solvent extracts of Angelica amurensis root (AAR). The yield of aqueous extract was the highest. The methanol extract had the highest total phenolic content and total flavonoid content. The aqueous extract showed the highest total carbohydrate content. Methanol and ethanol extracts showed high DPPH and ABTS radical-scavenging abilities, and high antioxidant activities in FRAP and CUPRAC assays. The extract of chloroform and water exhibited high ability to scavenge hydroxyl radicals. All extracts showed high inhibition of ß-carotene bleaching, ethyl acetate extract showed the best effect. Ethyl acetate extract exhibited the highest protection against cellular oxidative damage. The best extraction solvent for the active substance in AAR was methanol. AAR may act as a natural antioxidant.


Assuntos
Angelica , Antioxidantes , Carboidratos , Flavonoides , Extratos Vegetais , Solventes
11.
Plant Dis ; 103(12): 3002-3008, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31573432

RESUMO

Alternaria species are the most important fungal pathogens that attack various crops as well as fruit trees such as pear and cause black spot disease. Here, a loop-mediated isothermal amplification (LAMP) assay is developed for the detection of Alternaria species. A. alternata cytochrome b (cyt-b) gene was used to design two pairs of primers and amplified a 229-bp segment of Aacyt-b gene. The results showed that LAMP assay is faster and simpler than polymerase chain reaction (PCR). LAMP assay is highly sensitive method for the detection of about 1 pg of genomic DNA of A. alternata by using optimized concentration of MgCl2 (4 mM) in final LAMP reaction. In contrast, the limit of detection was 1 ng of target DNA via conventional PCR. Among the genomic DNA of 46 fungal species, only the tubes containing DNA of Alternaria spp. except A. porri, A. solani, and A. infectoria changed color from orange to yellowish green with SYBR Green I including the main pathogens of pear black spot. The yellowish green color was indicative of DNA amplification. Moreover, LAMP assay was used for testing infected tissues among 22 healthy and diseased pear tissues; the orange color changed to yellowish green for infected tissues only. Altogether, we conclude that cyt-b gene can be used for the detection of Alternaria spp. via LAMP assay, which is involved in pear black spot disease.


Assuntos
Alternaria , Técnicas de Amplificação de Ácido Nucleico , Pyrus , Alternaria/genética , Citocromos b/genética , Primers do DNA , Microbiologia de Alimentos/métodos , Limite de Detecção , Reação em Cadeia da Polimerase , Pyrus/microbiologia
12.
Plant Dis ; 102(9): 1741-1747, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30125168

RESUMO

Ustilaginoidea virens is an important fungus that causes rice false smut disease. This disease significantly reduces both grain yield and quality. Various methods have been developed for the detection of U. virens but most of these methods need sophisticated equipment such as a thermal cycler. Here, we present a loop-mediated isothermal amplification (LAMP) assay for the specific detection of U. virens. This assay used a specific region of the UvG-ß1 gene (212-bp region) to design six LAMP primers. The LAMP assay was optimized by the combination of rapidity, simplicity, and high sensitivity for the detection of about 1 pg of target genomic DNA in the reaction whereas, with polymerase chain reaction (PCR), there was no amplification of DNA with concentrations less than 1 ng. Among the genomic DNA of 22 fungus species and two strains of U. virens, only the tube containing the DNA of U. virens changed to yellowish green with SYBR Green I. The color change was indicative of DNA amplification. No DNA was amplified from either the other 22 fungus species or the negative control. Moreover, 20 spikelets and 22 rice seed samples were used for the detection of rice false smut via LAMP. The results were comparable with conventional PCR. We conclude that gene UvG-ß1 coupled with LAMP assay, can be used for the detection and identification of U. virens gene via LAMP.


Assuntos
Hypocreales/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Primers do DNA/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase , Sementes/microbiologia , Fatores de Tempo
13.
BMC Infect Dis ; 18(1): 316, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986649

RESUMO

BACKGROUND: GII noroviruses are a common cause of acute gastroenteritis (AGE) outbreaks in institutional settings globally. However, AGE outbreaks caused by GI norovirus, especially the GI.5 genotype, are relatively uncommon. METHODS: In February 2017, an AGE outbreak occurred in a primary school in Shanghai, China. An outbreak investigation was undertaken, and fecal specimens, rectal swabs, and environmental swabs were collected. Pathogen detection was performed and the positive specimens were characterized by gene sequencing. RESULTS: The descriptive epidemiological analysis suggested that this outbreak, involving 19 cases in two classes (designated classes A and B), was a small-scale propagated epidemic and person-to-person transmission was the most plausible transmission mode. The outbreak comprised two peaks, with 15 cases occurring in class A during the main peak and four cases occurring in class B in the subsequent minor peak. The primary attack rate was 38% and the secondary attack rate was 10%. Univariable logistic regression indicated that contacting a suspect case was a risk factor for norovirus infection, with an unadjusted OR of 5.6 (95% CI: 1.6-20.1). Six fecal specimens were positive for GI norovirus, with a single genotype, GI.5 norovirus, being involved, as characterized by genotyping. This outbreak was the first reported outbreak of GI.5 norovirus in China. CONCLUSIONS: This study implies that GI.5 norovirus is a potential agent of outbreaks spread by person-to-person transmission in institutional settings. The investigation highlights the importance of sensitive surveillance, timely isolation of individuals who are ill, adequate hand hygiene, and proper environmental disinfection for prevention and control of AGE outbreaks caused by norovirus.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/transmissão , Gastroenterite/epidemiologia , Criança , China/epidemiologia , Surtos de Doenças , Desinfecção , Feminino , Gastroenterite/virologia , Genótipo , Higiene das Mãos , Humanos , Masculino , Norovirus/genética , Norovirus/patogenicidade , Instituições Acadêmicas/estatística & dados numéricos
14.
PLoS One ; 13(1): e0191952, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29377926

RESUMO

Understory vegetation plays a vital role in regulating soil carbon (C) and nitrogen (N) characteristics due to differences in plant functional traits. Different understory vegetation types have been reported following aerial seeding. While aerial seeding is common in areas with serious soil erosion, few studies have been conducted to investigate changes in soil C and N cycling as affected by understory vegetation in aerially seeded plantations. Here, we studied soil C and N characteristics under two naturally formed understory vegetation types (Dicranopteris and graminoid) in aerially seeded Pinus massoniana Lamb plantations. Across the two studied understory vegetation types, soil organic C was significantly correlated with all measured soil N variables, including total N, available N, microbial biomass N and water-soluble organic N, while microbial biomass C was correlated with all measured variables except soil organic C. Dicranopteris and graminoid differed in their effects on soil C and N process. Except water-soluble organic C, all the other C and N variables were higher in soils with graminoids. The higher levels of soil organic C, microbial biomass C, total N, available N, microbial biomass N and water-soluble organic N were consistent with the higher litter and root quality (C/N) of graminoid vegetation compared to Dicranopteris. Changes in soil C and N cycles might be impacted by understory vegetation types via differences in litter or root quality.


Assuntos
Carbono/metabolismo , Nitrogênio/metabolismo , Pinus/metabolismo , Plantas/metabolismo , Solo/química , Biomassa , Carbono/química , Nitrogênio/química
15.
Sci Rep ; 7: 40954, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-28106107

RESUMO

Pilidiella granati, a causal agent of twig blight and crown rot of pomegranate, is an emerging threat that may cause severe risk to the pomegranate industry in the future. Development of a rapid assay for the timely and accurate detection of P. granati will be helpful in the active surveillance and management of the disease caused by this pathogen. In this study, a nested PCR method was established for the detection of P. granati. Comparative analysis of genetic diversity within 5.8S rDNA internal transcribed spacer (ITS) sequences of P. granati and 21 other selected fungal species was performed to design species-specific primers (S1 and S2). This primer pair successfully amplified a 450 bp product exclusively from the genomic DNA of P. granati. The developed method can detect 10 pg genomic DNA of the pathogen in about 6 h. This technique was successfully applied to detect the natural infection of P. granati in the pomegranate fruit. The designed protocol is rapid and precise with a high degree of sensitivity.


Assuntos
Ascomicetos/isolamento & purificação , Lythraceae/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase/métodos , Ascomicetos/classificação , Ascomicetos/genética , Primers do DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Frutas/microbiologia , RNA Ribossômico 5,8S/genética , Sensibilidade e Especificidade , Fatores de Tempo
16.
Ying Yong Sheng Tai Xue Bao ; 28(12): 3841-3847, 2017 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29696878

RESUMO

The distribution characteristics of carbon density under aerially seeded Pinus massoniana plantations in Ganzhou City of Jiangxi Province were studied. Total 15 factors, including site, stand, understory vegetation, litter and so on were selected to establish a relationship model between stand carbon density and influencing factors, and the main influencing factors were also screened. The results showed that the average carbon density was 98.29 t·hm-2 at stand level with soil layer (49.58 t·hm-2) > tree layer (45.25 t·hm-2) > understory vegetation layer (2.23 t·hm-2) > litter layer (1.23 t·hm-2). Significantly positive correlations were found among the tree, litter and soil layers, but not among the other layers. The main factors were tree density, avera-ge diameter at breast height (DBH), soil thickness, slope position, stand age and canopy density to affect carbon density in aerially seeded P. massoniana plantations. The partial correlation coefficients of the six main factors ranged from 0.331 to 0.434 with significance by t test. The multiple correlation coefficient of quantitative model I reached 0.796 with significance by F test (F=9.28). For stand density, the best tree density and canopy density were 1500-2100 plants·hm-2 and 0.4-0.7, respectively. The moderate density was helpful to improve ecosystem carbon sequestration. The carbon density increased with increasing stand age, DBH and soil thickness, and was higher in lower than middle and upper slope positions.


Assuntos
Sequestro de Carbono , Carbono , Pinus , China , Ecossistema , Solo
17.
Sci Rep ; 6: 33258, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27624858

RESUMO

A simple and rapid method for the detection of Tilletia horrida, the causal agent of rice kernel smut, in rice seeds is developed based on specific polymerase chain reaction (PCR). To design the specific primers for the detection of T. horrida, partial sequences of internal transcribed spacer (ITS) DNA region of T. horrida, T. controversa, T. walkeri, T. ehrhartae, T. indica and T. caries were analyzed and compared. A 503-bp fragment was amplified with the designed primers from the T. horrida genomic DNA. However, no PCR product was obtained from the DNA of other five Tilletia species and 22 fungal plant pathogens tested in the present work indicating the specificity of the primers for the detection of T. horrida. The PCR was performed by directly using the spores, isolated from the 21 different rice seed samples, as template DNA. The T. horrida was detected in 6 of the samples, indicating that 28.6% of the rice samples were contaminated with the kernel smut pathogen. This simple PCR based diagnostic assay can be applied for the direct and rapid detection and identification of T. horrida to screen large numbers of rice seed samples.


Assuntos
Basidiomycota/isolamento & purificação , DNA Fúngico/isolamento & purificação , Oryza/microbiologia , Doenças das Plantas/microbiologia , Basidiomycota/genética , Basidiomycota/patogenicidade , DNA Fúngico/genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Doenças das Plantas/genética , Reação em Cadeia da Polimerase , Sementes/genética , Sementes/microbiologia
18.
PLoS One ; 10(8): e0133294, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26241912

RESUMO

In this study, an individual tree crown ratio (CR) model was developed with a data set from a total of 3134 Mongolian oak (Quercus mongolica) trees within 112 sample plots allocated in Wangqing Forest Bureau of northeast China. Because of high correlation among the observations taken from the same sampling plots, the random effects at levels of both blocks defined as stands that have different site conditions and plots were taken into account to develop a nested two-level nonlinear mixed-effect model. Various stand and tree characteristics were assessed to explore their contributions to improvement of model prediction. Diameter at breast height, plot dominant tree height and plot dominant tree diameter were found to be significant predictors. Exponential model with plot dominant tree height as a predictor had a stronger ability to account for the heteroskedasticity. When random effects were modeled at block level alone, the correlations among the residuals remained significant. These correlations were successfully reduced when random effects were modeled at both block and plot levels. The random effects from the interaction of blocks and sample plots on tree CR were substantially large. The model that took into account both the block effect and the interaction of blocks and sample plots had higher prediction accuracy than the one with the block effect and population average considered alone. Introducing stand density into the model through dummy variables could further improve its prediction. This implied that the developed method for developing tree CR models of Mongolian oak is promising and can be applied to similar studies for other tree species.


Assuntos
Modelos Biológicos , Dinâmica não Linear , Quercus/anatomia & histologia , China , Quercus/crescimento & desenvolvimento
19.
Mol Plant Microbe Interact ; 27(7): 655-63, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24678831

RESUMO

The interaction between plants and plant-growth-promoting rhizobacteria (PGPR) is a complex, reciprocal process. On the one hand, plant compounds such as carbohydrates and amino acids serve as energy sources for PGPR. On the other hand, PGPR promote plant growth by synthesizing plant hormones and increasing mineral availability in the soil. Here, we evaluated the growth-promoting activity of Bacillus subtilis OKB105 and identified genes associated with this activity. The genes yecA (encoding a putative amino acid/polyamine permease) and speB (encoding agmatinase) are involved in the secretion or synthesis of polyamine in B. subtilis OKB105. Disruption of either gene abolished the growth-promoting activity of the bacterium, which was restored when polyamine synthesis was complemented. Moreover, high-performance liquid chromatography analysis of culture filtrates of OKB105 and its derivatives demonstrated that spermidine, a common polyamine, is the pivotal plant-growth-promoting compound. In addition, real-time polymerase chain reaction analysis revealed that treatment with B. subtilis OKB105 induced expansin gene (Nt-EXPA1 and Nt-EXPA2) expression and inhibited the expression of the ethylene biosynthesis gene ACO1. Furthermore, enzyme-linked immunosorbent assay analysis showed that the ethylene content in plant root cells decreased in response to spermidine produced by OKB105. Therefore, during plant interactions, OKB105 may produce and secrete spermidine, which induces expansin production and lowers ethylene levels.


Assuntos
Bacillus subtilis/metabolismo , Espermidina/biossíntese , Espermidina/farmacologia , Tabaco/efeitos dos fármacos , Tabaco/crescimento & desenvolvimento , Etilenos , Plasmídeos/genética , Fatores de Tempo , Tabaco/microbiologia
20.
J Chromatogr A ; 1304: 241-5, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-23880470

RESUMO

Fe3O4@MIL-100 core-shell magnetic microspheres were, for the first time, used as the sorbent for the magnetic solid-phase extraction (MSPE) of polychlorinated biphenyls at trace levels in environmental water samples. GC coupled with tandem MS was used for sample quantification and detection. The Box-Behnken design was used to determine the optimum extraction parameters influencing extraction efficiency through response surface methodology. Under the optimized conditions, the developed method showed good linearity within the range of 5-4000ngL(-1), low limits of detection (1.07-1.57ngL(-1); signal-to-noise ratio=3:1), and good extraction repeatability (relative standard deviation<12%; n=5). Environmental samples collected from the Yellow River, local lake, wastewater, and snow water were processed using the developed method. The results demonstrated that the Fe3O4@MOF core-shell magnetic microspheres are promising sorbents in the MSPE of aromatic pollutants from environmental water samples.


Assuntos
Nanopartículas de Magnetita/química , Compostos Organometálicos/química , Bifenilos Policlorados/isolamento & purificação , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Rios/química , Razão Sinal-Ruído , Águas Residuárias/análise
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