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1.
Zhonghua Nei Ke Za Zhi ; 63(7): 660-665, 2024 Jul 01.
Artigo em Chinês | MEDLINE | ID: mdl-38951089

RESUMO

Objective: To investigate the clinical and electrophysiological characteristics of patients with amyotrophic lateral sclerosis (ALS) with positive repetitive nerve stimulation (RNS) test results on the accessory nerve and negative needle electromyography (EMG) test results on the sternocleidomastoid with the goal to enrich the knowledge of disease progression in patients with ALS. Methods: The clinical data of 612 patients diagnosed with ALS at the Neurology Department of the First Medical Center, Chinese PLA General Hospital from June 2016 to August 2022 were collected. In total, 267 cases had undergone EMG tests on the sternocleidomastoid following a positive 3 Hz RNS test result on the accessory nerve, who were selected as the study subjects. The differences in clinical indicators were compared between RNS (+)/EMG (-) group and RNS (+)/EMG (+) group. A binomial distribution model with multiple variables was built to quantitatively analyze the major factors and their effects. Results: At the initial visit, 15.8% of patients with ALS were 3 Hz RNS (+) on the accessory nerve and EMG (-) on the ipsilateral sternocleidomastoid, accounting for 36.3% of RNS (+) patients. The decremental range of the 3 Hz RNS test delivered to the accessory nerve in these patients [-14% (-19%, -12%)] was lower than that in patients with RNS (+)/EMG (+) [-17% (-23%, -13%)] (P<0.05), while the ratio of upper limb onset (64.9%) and non-definite diagnosis (28.9%) were higher [54.7% and 13.5% for patients with RNS (+)/EMG (+), P<0.05]. Furthermore, the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) score [40 (37, 42)], body mass index (BMI) [23.8 (22.0, 25.4) kg/m2] and forced vital capacity (FVC) [92.8% (76.6%, 103.8%)] were higher in patients with RNS(+)/EMG(+) (P<0.05). The multivariate model suggested that, in patients with RNS (+)/EMG (-), the ratio of upper limb onset to lower limb onset was 1.04, while that of upper limb onset to bulbar onset was 2.02, and that of lower limb onset to bulbar onset was 1.94. The ratio of non-definite ALS to definite ALS was 1.13. The ALSFRS-R score, BMI, and FVC had a protective contribution to the electrophysiological function of the motor neurons. The ratio of the effect size of the ALSFRS-R or BMI to that of FVC was 3.37 and 1.14, respectively. Conclusions: Patients with ALS that were 3 Hz RNS (+) on the accessory nerve and EMG (-) on the ipsilateral sternocleidomastoid had a smaller decremental range of the compound muscle action potential amplitude, and a higher proportion of upper limb onset and non-definite ALS. A higher ALSFRS-R score, BMI, and FVC have a protective effect to the electrophysiological function of motor neurons. The effect size of the ALSFRS-R score is the largest, followed by BMI and FVC.


Assuntos
Esclerose Lateral Amiotrófica , Eletromiografia , Neurônios Motores , Humanos , Esclerose Lateral Amiotrófica/fisiopatologia , Neurônios Motores/fisiologia , Junção Neuromuscular/fisiopatologia , Estimulação Elétrica , Nervo Acessório/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade
2.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772947

RESUMO

We introduce a LabVIEW-based control program that significantly improves the efficiency and flexibility in positioning and shooting solid targets in laser-plasma experiments. The hardware driven by this program incorporates a target positioning subsystem and an imaging subsystem, which enables us to install up to 400 targets for one experimental campaign and precisely adjust them in six freedom degrees. The overall architecture and the working modes of the control program are demonstrated in detail. In addition, we characterized the distributions of target positions of every target holder and simultaneously saved the target images, resulting in a large dataset that can be used to train machine learning models and develop image recognition algorithms. This versatile control system has become an indispensable platform when preparing and conducting laser-plasma experiments.

3.
Eur Rev Med Pharmacol Sci ; 25(2): 890-897, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577043

RESUMO

OBJECTIVE: The aim of this study was to explore the associations of interleukin-1ß (IL-1ß) and IL-6 gene polymorphisms with the pathogenesis of Parkinson's disease. PATIENTS AND METHODS: A total of 200 patients with Parkinson's disease in our hospital were collected as the disease group. Meanwhile, 200 healthy subjects were taken as the control group. Peripheral blood samples were drawn from all research subjects. The polymorphic regions of IL-1ß and IL-6 were amplified via polymerase chain reaction (PCR). Moreover, the polymorphisms were detected and analyzed, followed by further analysis based on the changes in gene expressions and Hoehn-Yahr grade of patients. RESULTS: The allele distributions at IL-1ß rs571556428 (p=0.015) and IL-6 rs543214973 (p=0.012) were statistically different between control group and disease group. In disease group, the G allele frequency at IL-1ß rs571556428 and T allele frequency at IL-6 rs543214973 were significantly higher (p<0.05). Genotype distributions at IL-1ß rs572292175 (p=0.017) and rs571556428 (p=0.000), and IL-6 rs543214973 (p=0.002) in disease group were also different from those in control group. In addition, the frequencies of CT genotype at IL-1ß rs572292175, AA genotype at IL-1ß rs571556428 and AA genotype at IL-6 rs543214973 in disease group were significantly lower (p<0.05). After modeling and analysis, it was found that the distribution of recessive model at IL-1ß rs571556428 (p=0.012) and IL-6 rs543214973 (p=0.014) in disease group exhibited significant differences from those in control group. The frequencies of TA haplotype at IL-1ß rs572292175 and rs571556428 (p=0.038) and GA haplotype at IL-6 rs1474348 and rs543214973 (p=0.047) in disease group were lower than those in control group (p<0.05). The polymorphisms at IL-1ß rs571556428 and IL-6 rs1474348 were significantly associated with gene expression (p<0.05). Moreover, the expressions of IL-1ß and IL-6 rose significantly in patients with GG genotype at rs571556428 and CG genotype at rs1474348, respectively (p<0.05). Furthermore, the polymorphism at IL-1ß rs571556428 was significantly correlated with the grade of Parkinson's disease (p=0.000). Parkinson's disease was in a higher grade (grade 4-5) in patients with AA genotype, whereas in a lower grade (grade 1-2) in patients with GG and AG genotypes. CONCLUSIONS: IL-1ß and IL-6 gene polymorphisms are significantly associated with the pathogenesis of Parkinson's disease.


Assuntos
Interleucina-1beta/genética , Interleucina-6/genética , Doença de Parkinson/genética , Polimorfismo Genético/genética , Feminino , Humanos , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/sangue , Doença de Parkinson/diagnóstico
4.
Eur Rev Med Pharmacol Sci ; 24(22): 11569-11577, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33275223

RESUMO

OBJECTIVE: The aim of this study was to explore the regulatory effect of micro ribonucleic acid (miR)-20a on nuclear factor-κB (NF-кB) in liver cancer Huh-7 cells, and to elucidate its influence on the chemosensitivity of Huh-7 cells. MATERIALS AND METHODS: Huh-7 cells with overexpression of miR-20a or knockout of miR-20a were first constructed. Quantitative polymerase chain reaction (qPCR) was adopted to detect the expression level of miR-20a in each group of cells. The sensitivity of cells to cisplatin and doxorubicin in each group was measured using methyl thiazolyl tetrazolium (MTT) assay, and the 50% inhibitory concentration (IC50) was calculated. Hoechst 33258 staining was performed to detect the apoptosis of cells in each group. Furthermore, the expression levels of apoptosis-associated proteins and the NF-кB signaling pathway-related proteins in each group of cells were determined via Western blotting. RESULTS: The expression level of miR-20a in blank control group was considerably higher than that in knockout group (p<0.01). Meanwhile, cells in overexpression group exhibited a notably higher expression level of miR-20a than blank control group (p<0.01). Cells in knockout group had dramatically enhanced sensitivity to doxorubicin and cisplatin (p<0.01), with a prominently decreased IC50 value (p<0.01). However, cells in overexpression group exhibited remarkably weakened sensitivity (p<0.01) and increased IC50 value (p<0.01). After treatment with doxorubicin and cisplatin, the apoptosis level of cells rose substantially in knockout group (p<0.01), whereas declined significantly in overexpression group (p<0.01). Moreover, knockout group exhibited a notably elevated expression level of Caspase-3 (p<0.01), and a considerably decreased ratio of B-cell lymphoma 2 (Bcl-2)/Bcl-2 associated X protein (Bax) (p<0.01). The expression level of Caspase-3 declined remarkably (p<0.01), however, the ratio of Bcl2/Bax increased substantially (p<0.01) in overexpression group. The expression level of NF-кB inhibitor beta (NF-кBIB) was markedly up-regulated (p<0.01), while the expression levels of Livin and Survivin declined remarkably (p<0.01) in knockout group. Furthermore, overexpression group had a considerably decreased expression level of NF-кBIB (p<0.01), but notably increased expression levels of Livin and Survivin (p<0.01). CONCLUSIONS: MiR-20a up-regulates the expressions of the downstream proteins Livin and Survivin, decreases the expressions of apoptosis-associated proteins, weakens the sensitivity of cells to chemotherapy drugs and lowers the apoptosis level of cells by activating the NF-кB signaling pathway in liver cancer Huh-7 cells.


Assuntos
Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Apoptose , Proliferação de Células , Sobrevivência Celular , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Células Tumorais Cultivadas
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(5): 949-953, 2019 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-31624404

RESUMO

OBJECTIVE: To evaluate the effect of different triangular flap design and healing procedure on the sequelae after extraction of impacted lower third molars. METHODS: In this prospective, split-mouth study, 60 healthy patients with bilateral, symmetrically fully impacted lower third molars (LM3) were included, of whom 30 patients with totally bony impacted LM3 were allocated into group A, while the other patients with partially bony impacted LM3 were allocated into group B. All the teeth were extracted by the same surgeon. Triangular flap was used on one side, and the wound was primarily closed with two sutures (TF-P). On the other side, modified triangular flap was used with a triangular region of mucosa posterior to LM2 removed during operation, and a triangular soft tissue defect was left for drainage after suture (MTF-S). The patients were followed up on postoperative days 1, 3 and 7. Clinical parameters included postoperative pain, swelling, and trismus. Distal probing depth of adjacent second molar was assessed 6 months after extraction. Doctors responsible for the evaluation did not know the group and flap design. Paired sample t test was used to analyze the differences of postoperative sequelae between the two strategies. RESULTS: In group A, MTF-S strategy could reduce postoperative pain, ibuprofen consumption, and swelling significantly compared with TF-P strategy on the postoperative 1st and 3rd days (P<0.05). Besides, the trismus in the patients with TF-P strategy was more serious than that with MTF-S strategy on the postoperative 1st, 3rd and 7th days (P<0.05). However, statistic difference between the two strategies in pain, swelling and trismus was not detected in group B. Additionally, the VAS score in the patients with MTF-S strategy in group B increased slightly on the postoperative 4th day. The probing depth of the adjacent second molar was evaluated 6 months after extraction. Statistic difference was not detected between MTF-S strategy and TF-P strategy in the both groups. CONCLUSION: Modified triangular flap with secondary healing procedure could effectively reduce the postoperative complications of totally bony impacted LM3. However, the difference between the two strategies in the probing depth of the adjacent second molar was not statically significant 6 months after extraction.


Assuntos
Dente Serotino , Dente Impactado , Edema , Humanos , Mandíbula , Dor Pós-Operatória , Complicações Pós-Operatórias , Estudos Prospectivos , Retalhos Cirúrgicos , Extração Dentária
6.
Zhonghua Zhong Liu Za Zhi ; 40(9): 696-702, 2018 Sep 23.
Artigo em Chinês | MEDLINE | ID: mdl-30293397

RESUMO

Objective: To investigate the efficacy and safety of lobaplatin (LBP) plus S-1 for advanced gastric cancer (AGC) and determine the potential role of circulating tumor cells (CTC) for predicting the therapeutic response and prognosis. Methods: From January 2014 to February 2015, 64 consecutive patients with AGC received lobaplatin plus S-1 chemotherapy in Liaocheng People's Hospital. The clinical features, clinical response, adverse effects, prognosis and CTC pre- and post-treatment were retrospectively analyzed. The correlation between CTC and patients' disease control rate (DCR), objective response rate (ORR), progression free survival (PFS) as well as overall survival (OS) were investigated. Results: All 64 patients completed 2 cycles of chemotherapy.The number of patients who achieved complete regression, partial regression, stable and progression were 0, 24 (37.5%), 18 (28.1%) and 22 (34.4%), respectively. ORR was 37.5% and DCR was 65.6%. The median PFS was 10.8 months(95%CI 7.1-12.0) and the median OS was 16.1 months(95%CI 12.4-18.8). The ORR and PFS were not significantly different between patients with baseline CTC≥2 and CTC<2 (25.0% vs 53.6%, P=0.150; 6.2 months vs 7.5 months, P=0.780), while the DCR and OS were significantly different (45.9% vs 90.0%, P=0.008; 10.5 months vs 17.2 months, P<0.001). After 2 cycles of chemotherapy, the ORR and DCR in patients with CTC≥2 were 16.7% and 45.9%, respectively, which were significantly lower than those observed in patients with CTC<2 (50.0% and 90.0%, respectively). The former also had shorter median PFS and OS (6.6 months vs 8.9 months, 8.4 months vs 15.0 months, respectively). Patients with persistently CTC<2 or those exhibiting an conversion to CTC<2 following chemotherapy had an improved PFS and OS, while patients with persistently CTC≥2 or those exhibiting an conversion to CTC≥2 following therapy had shorter PFS and OS.The most frequent adverse effects were grade 1 or 2 gastrointestinal discomfort and myelosuppression. No patients discontinued chemotherapy because of adverse events. Conclusions: Lobaplatin plus S-1 had manageable safety profile and promising antitumor activity in patients with AGC. CTC could be used as a biomarker in evaluating therapeutic response and predicting their prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclobutanos/administração & dosagem , Células Neoplásicas Circulantes , Compostos Organoplatínicos/administração & dosagem , Ácido Oxônico/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Tegafur/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclobutanos/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Combinação de Medicamentos , Humanos , Compostos Organoplatínicos/efeitos adversos , Ácido Oxônico/efeitos adversos , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Neoplasias Gástricas/sangue , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Tegafur/efeitos adversos
7.
Zhonghua Gan Zang Bing Za Zhi ; 26(7): 553-556, 2018 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-30317783

RESUMO

Hepatic encephalopathy (HE) is caused by severe liver disease or portal shunt. Metabolic disorders and central nervous system dysfunctions are the main symptoms of this syndrome. Ammonia is considered to play a central role in the pathogenesis of HE. Helicobacter pylori (H. pylori) have been suggested as a possible source of ammonia production because of its high urease content. However, the relationship between H.pylori and blood ammonia and HE, as well as the therapeutic effect of H.pylori eradication on HE, is inconclusive, and the results are full of contradictions. The aim of this review is to summarize current knowledge on the association of H. pylori with HE and to address the question of whether H. pylori eradication may be beneficial in the management of HE.


Assuntos
Amônia/análise , Infecções por Helicobacter/sangue , Helicobacter pylori/fisiologia , Encefalopatia Hepática/sangue , Cirrose Hepática/sangue , Infecções por Helicobacter/complicações , Encefalopatia Hepática/complicações , Humanos , Cirrose Hepática/complicações , Estômago/química
8.
Sci Rep ; 6: 27633, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27273170

RESUMO

Ultrafast betatron x-ray emission from electron oscillations in laser wakefield acceleration (LWFA) has been widely investigated as a promising source. Betatron x-rays are usually produced via self-injected electron beams, which are not controllable and are not optimized for x-ray yields. Here, we present a new method for bright hard x-ray emission via ionization injection from the K-shell electrons of nitrogen into the accelerating bucket. A total photon yield of 8 × 10(8)/shot and 10(8 )photons with energy greater than 110 keV is obtained. The yield is 10 times higher than that achieved with self-injection mode in helium under similar laser parameters. The simulation suggests that ionization-injected electrons are quickly accelerated to the driving laser region and are subsequently driven into betatron resonance. The present scheme enables the single-stage betatron radiation from LWFA to be extended to bright γ-ray radiation, which is beyond the capability of 3(rd) generation synchrotrons.

9.
Sci Rep ; 6: 27363, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27250660

RESUMO

Neutron energy is directly correlated with the energy of the incident ions in experiments involving laser-driven nuclear reactions. Using high-energy incident ions reduces the energy concentration of the generated neutrons. A novel "laser-collider" method was used at the Shenguang II laser facility to produce monoenergetic neutrons via (7)Li (d, n) nuclear reactions. The specially designed K-shaped target significantly increased the numbers of incident d and Li ions at the keV level. Ultimately, 13.3 MeV neutrons were obtained. Considering the time resolution of the neutron detector, we demonstrated that the produced neutrons were monoenergetic. Interferometry and a Multi hydro-dynamics simulation confirmed the monoenergetic nature of these neutrons.

10.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(1): 25-9, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-26792184

RESUMO

OBJECTIVE: To analyze the distribution of types and characteristics of periodontal diseases in 34 677 patients visiting the Department of Periodontology, Peking University School and Hospital of Stomatology. METHODS: Clinical data of 34 677 patients who had the electronic periodontal examination charts from 2007 to 2012 were collected and analyzed. RESULTS: Out of 34 677 patients, 32 517 (93.77%) were diagnosed as chronic periodontitis(CP), 1 642(4.74%) were aggressive periodontitis(AgP) and the rest 518(1.49%) patients were classified into some other types of periodontitis. There were more female patients than male ones. Most of patients were between 25 to 54 years olds. Only 7 306(21.07%) patients had more than two periodontal examination charts which represented regular re-visits to the doctors. The majority of patients had severe periodontitis. CONCLUSIONS: Most of the patients visiting the Department of Periodontology were older aged and diagnosed chronic periodontitis. They had more severe periodontitis conditions but less re-visits. Therefore it is very important for dentists to enhance the oral health education and make early diagnosis and treatment of periodontal diseases for patients. Dentists also should do more follow-up and maintenance works for patients after the initial treatments.


Assuntos
Periodontite/classificação , Adulto , Distribuição por Idade , Periodontite Agressiva/epidemiologia , Periodontite Crônica/epidemiologia , Odontólogos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite/epidemiologia , Distribuição por Sexo
11.
Rev Sci Instrum ; 86(6): 063505, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26133837

RESUMO

Neutron yields have direct correlation with the energy of incident deuterons in experiments of laser deuterated target interaction [Roth et al., Phys. Rev. Lett. 110, 044802 (2013) and Higginson et al., Phys. Plasmas 18, 100703 (2011)], while deuterated plasma density is also an important parameter. Experiments at the Shenguang II laser facility have produced neutrons with energy of 2.45 MeV using d (d, n) He reaction. Deuterated foil target and K-shaped target were employed to study the influence of plasma density on neutron yields. Neutron yield generated by K-shaped target (nearly 10(6)) was two times higher than by foil target because the K-shaped target results in higher density plasma. Interferometry and multi hydro-dynamics simulation confirmed the importance of plasma density for enhancement of neutron yields.

12.
Rev Sci Instrum ; 85(11): 113304, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430107

RESUMO

We report an efficient Mo Kα x-ray source produced by interaction of femtosecond Ti: sapphire laser pulses with a solid Molybdenum target working at 1 kHz repetition rate. The generated Mo Kα x-ray intensity reaches to 4.7 × 10(10) photons sr(-1) s(-1), corresponding to an average power of 0.8 mW into 2π solid angle. The spatial resolution of this x-ray source is measured to be 26 lp/mm. With the high flux and high spatial resolution characteristics, high resolving in-line x-ray radiography was realized on test objects and large size biological samples within merely half a minute. This experiment shows the possibility of laser plasma hard x-ray source as a new low cost and high resolution system for radiography and its ability of ultrafast x-ray pump-probe study of matter.

13.
Opt Express ; 22(11): 12836-44, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24921480

RESUMO

We report the generation of a 6 pC, 23 MeV electron bunch with the energy spread ± 3.5% by using 2 TW, 80 fs high contrast laser pulses interacting with helium gas targets. Within the optimized experimental condition, we obtained quasi-monoenergetic electron beam with an ultra-small normalized divergence angle of 92 mrad, which is at least 5 times smaller than the previous LPA-produced bunches. We suggest the significant decrease of the normalized divergence angles is due to smooth transfer from SM-LWFA to LWFA. Since the beam size in LPA is typically small, this observation may explore a simple way to generate ultralow normalized emittance electron bunches by using small-power but high-repetition-rate laser facilities.

14.
Plant Dis ; 98(5): 692, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708513

RESUMO

Amorphophallus muelleri is a perennial tuberous plant in the family Araceae. The name konjac is commonly used for the species of genus Amorphophallus that produce a polysaccharide, glucomannan. The latter, called konjac glucomannan, is extracted from the tubers of these species. Glucomannan is an excellent gelling agent used in food, pharmaceutical and chemical industry, a specialty crop grown as a source of glucomannan for industrial use. It is an important cash crop and thus contributes to poverty alleviation in southwest China. Its planting area is about 150 million mu (10 million ha). In July 2012, symptoms of an unknown blight were observed on 5 to 10% of A. muelleri flowers and seeds being grown for commercial seed production. Greenhouses temperatures ranged from 20 to 34°C (avg. 26°C). A light grey mycelium was observed on symptomatic tissues, especially flowers. Severely infected flowers and stems eventually rotted, then dried out. Diseased tissue was excised from affected flowers and surfaces and disinfected with 1% sodium hypochlorite, followed by 70% alcohol. The tissue was then rinsed in sterile distilled water, plated on potato dextrose agar (PDA), and incubated at 26°C. Mycelial growth on PDA was initially whitish and turned gray with age. Dark appearing conidiophores bore botryose heads of hyaline, ellipsoid, unicellular conidia, grey in mass, measuring 7.2 (6.2 to 9.5) × 5.3 (4.5 to 6.0) µm. Black, irregular sclerotia formed at random in the culture. These morphological features were typical of those described for Botrytis cinerea (2). The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced (1). BLAST analysis of a 557-bp segment had a 99% similarity with the sequence of Botryotinia fuckeliana (anamorph = B. cinerea). The representative nucleotide sequence has been assigned the GenBank Accession No. KC999986. On the basis of morphological and molecular results, the fungus isolated from diseased konjac flowers and flower tissue was confirmed to be B. cinerea. Pathogenicity tests: Inoculum was prepared from 7-day-old cultures on PDA. Six flowering A. muelleri in 1-liter pots were spray inoculated with a 1.0 × 106 conidia/ml suspension from 7-day-old PDA cultures. As a control, six healthy plants were sprayed with sterile distilled water. Each plant was covered with a transparent polyethylene bag for 3 days and maintained in a greenhouse at temperatures between 20 and 26°C. After 8 days, small, round to irregular brown spots developed on both flowers and stems, which finally blighted. Water-treated plants remained symptomless. Koch's postulates were fulfilled when the pathogen was re-isolated from the diseased organs. Blight on common calla lily (calla lily and Amorphophallus are in the same family, different genera) flower attributed to B. cinerea was previously reported in Argentina (3). To our knowledge, this is the first report of the presence of B. cinerea on A. muelleri in China. References: (1) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (2) M. B. Ellis. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, England, 1971. (3) M. C. Rivera and S. E. Lopez. Plant Dis. 90:970, 2006.

15.
Sci Rep ; 3: 1912, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23715033

RESUMO

Hard X-ray sources from femtosecond (fs) laser-produced plasmas, including the betatron X-rays from laser wakefield-accelerated electrons, have compact sizes, fs pulse duration and fs pump-probe capability, making it promising for wide use in material and biological sciences. Currently the main problem with such betatron X-ray sources is the limited average flux even with ultra-intense laser pulses. Here, we report ultra-bright betatron X-rays can be generated using a clustering gas jet target irradiated with a small size laser, where a ten-fold enhancement of the X-ray yield is achieved compared to the results obtained using a gas target. We suggest the increased X-ray photon is due to the existence of clusters in the gas, which results in increased total electron charge trapped for acceleration and larger wiggling amplitudes during the acceleration. This observation opens a route to produce high betatron average flux using small but high repetition rate laser facilities for applications.


Assuntos
Elétrons , Gases/química , Lasers , Aceleradores de Partículas , Fótons , Espalhamento de Radiação , Raios X
16.
Genet Mol Res ; 11(3): 2523-33, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22869072

RESUMO

The gene HtNB confers non-lesion resistance to the fungal pathogen Exserohilum turcicum in maize. To map this gene, we developed two F2 populations, P111 (resistant line) x HuangZao 4 (susceptible line) and P111 x B73 (susceptible). HtNB was located on chromosome 8.07 bin, flanked by MAC216826-4 and umc2218 at distances of 3.3 and 3.4 cM, respectively. HtNB appears to be a new gene responsible for resistance to northern corn leaf blight. Functions of the genes in the region between umc1384 and umc2218 were predicted. In addition, several genes were found to be related to disease resistance, such as the genes encoding Ser/Thr protein kinase and protein-like leaf senescence.


Assuntos
Ascomicetos/fisiologia , Mapeamento Cromossômico/métodos , Resistência à Doença/genética , Genes de Plantas/genética , Endogamia , Zea mays/genética , Zea mays/microbiologia , Segregação de Cromossomos/genética , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Resistência à Doença/imunologia , Ligação Genética , Marcadores Genéticos , Genótipo , Indonésia , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Zea mays/imunologia
17.
Plant Dis ; 96(12): 1821, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30727268

RESUMO

Helwingia chinensis Batal is distributed in the western and southern regions of China. The aerial part of this plant has long been used to treat dysentery, hematochezia, and swelling. An outbreak of cankers and dieback was observed for the first time on H. chinensis in China during June of 2010. Disease symptoms included dieback of shoots and branches, lesions, and canker formation on the stems. In order to identify the causal agent(s) of this canker disease, samples composed of inner bark and woody tissues were collected from the junction of healthy and diseased tissues of declining trees from Kunming and Wenshan districts of China during July to October of 2010. Pieces of surface-sterilized tissue samples were plated on potato dextrose agar (PDA) and incubated at 26°C. Fungal colonies developed copious, white, aerial mycelium that became dark green with age. Pycnidia started to develop after 20 days. Macroconidia, which were 20 to 29 × 4 to 6 µm, were hyaline, aseptate, and fusiform. No fungus was isolated from water-inoculated tissues of control plants and healthy trees. Identity was confirmed by analysis of the rDNA internal transcribed spacer region (ITS1-5.8S-ITS2) with primers ITS1 and ITS4. BLAST searches showed 99% identity with Botryosphaeria dothidea isolates from GenBank (Accession Nos. HQ660454 and FJ790846). Representative sequences of B. dothidea from H. chinensis from China have been deposited in GenBank (Accession No. JQ766122). On the basis of morphological and molecular results, the fungus isolated from diseased H. chinensis was confirmed to be B. dothidea. Pathogenicity tests were conducted by stem inoculation of 1-year-old H. chinensis seedlings. Mycelial plugs (3 to 4 mm in diameter) of B. dothidea from actively growing colonies were applied to same-sized bark wounds on the middle point of the stems. Control seedlings were inoculated with sterile PDA plugs. Inoculated and control seedlings (three each) were kept in a greenhouse and watered as needed. After 4 weeks, all H. chinensis seedlings developed vascular tissue discoloration and leaf wilting; no such symptoms were manifested by seedlings in the control treatment. B. dothidea was reisolated from all B. dothidea-inoculated, symptomatic tissues, fulfilling Koch's postulates. In China, B. dothidea has previously been reported to cause canker and dieback disease of Eucalyptus grandis (2) and gummosis of peach (1); however, to our knowledge, this is the first report of B. dothidea causing canker and dieback on H. chinensis. References: (1) Y. Ko et al. Plant Pathol. Bull. 1:70, 1992. (2) L. Yu et al. Plant Dis. 93:764, 2009.

18.
Plant Dis ; 96(11): 1697, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30727480

RESUMO

Blueberry (Vaccinium spp.) production in southwest and northeast China has grown to over 100,000 ha in the last 20 years thanks to the fruit's high nutritional and economic value. As blueberry acreage increases, the diversity of diseases and challenges for control are gaining more attention. In August 2010, stem and branch blight occurred on Highbush Blueberries (Vaccinium corymbosum L.) at commercial farms in Lijiang and Zongdian, Yunnan Province (southwestern China), with crop damage ranging from 10 to 15%. Typical symptoms of the disease were blight and dieback on the stems with lesions extending along entire branches. Diseased samples (phloem and xylem sectors in the wood) were washed with running tap water, disinfected with 2% sodium hypochlorite, then 70% alcohol, rinsed in sterile distilled water, plated on potato dextrose agar (PDA), and incubated at 28°C. Fungal isolates developed copious, white aerial mycelium that became dark gray after 4 to 5 days and formed black pycnidia after 18 days. Conidia were hyaline, aseptate, thin walled, fusiform, and measured 21 to 27 × 4 to 6 µm. Identity was confirmed by analysis of the ribosomal DNA internal transcribed spacer region ITSI-5.8S -ITS2 with primers ITS1 and ITS4. BLAST searches showed 99% identity with Botryosphaeria dothidea isolates from GenBank (Accession Nos. AB693904 and JF800139). Representative sequences of B. dothidea from Highbush Blueberries from China were deposited into GenBank (Accession No. JX096631). On the basis of morphological and molecular results, the fungus isolated from diseased Highbush Blueberries stem was confirmed to be B. dothidea. Pathogenicity tests were conducted on 2-year-old blueberry seedlings (Highbush Blueberries). Mycelial plugs (2 to 3 mm in diameter) of B. dothidea from actively growing colonies (PDA) were applied to same-size bark wounds in the center of the stems. Inoculation wounds were wrapped with Parafilm. Control seedlings received sterile PDA plugs. Inoculated and control seedlings (five each) were kept in a greenhouse and watered as needed. After 12 days, all of the inoculated but none of the control blueberry seedlings showed dark vascular stem tissue. B. dothidea was reisolated from symptomatic tissues, thus fulfilling Koch's postulates. No symptoms were visible in the control seedlings. B. dothidea has been reported as a pathogen of sycamore (3), olives (1), and peach (2). However, no research has been conducted on stem blight of blueberry caused by B. dothidea in southwest or mainland China. To our knowledge, this is the first report of B. dothidea on blueberry in southwest China. References: (1) M. Chattaoui, et al. Plant Dis. 95:770, 2011. (2) Y. Ko et al. Plant Pathol. Bull. 1:70, 1992. (3) E. Turco, et al. Plant Dis. 90:1106, 2006.

19.
Br J Pharmacol ; 162(8): 1805-18, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21232035

RESUMO

BACKGROUND AND PURPOSE: The combination of Chinese herbs, Astragali Radix and Angelicae Sinensis Radix, could alleviate renal interstitial fibrosis. Astragaloside IV (AS-IV) and ferulic acid (FA) are the two major active constituents in this combination. In this study, we employed rats with unilateral ureteral obstruction to determine whether AS-IV and FA have the same renoprotective effects and investigated the mechanisms of this action. EXPERIMENTAL APPROACH: Renal pathological changes were evaluated after treatment with AS-IV, FA or AS-IV + FA (AF) for 10 days. Meanwhile, the expression of transforming growth factor ß(1) (TGF-ß(1) ), fibronectin, α-smooth muscle actin (α-SMA), phosphorylation of c-Jun NH(2) -terminal kinase (p-JNK) and nitric oxide (NO) production in kidney were determined. The expressions of fibronectin, α-SMA, mitogen-activated protein kinases [JNK, extracellular signal-regulated kinases (ERK), P38] in TGF-ß(1) -treated NRK-49F cells or interleukin-1-treated HK-2 cells after AS-IV, FA or AF were assessed. KEY RESULTS: AF alleviated the infiltration of mononuclear cells, tubular atrophy and interstitial fibrosis; reduced the expression of fibronectin, α-SMA, TGF-ß(1) and p-JNK; and dramatically increased the production of NO in obstructed kidneys. Neither AS-IV nor FA alone improved renal damage, but both increased NO production. AF inhibited α-SMA and fibronectin expression in NRK-49F or HK-2 cells. Furthermore, AF significantly inhibited IL-1ß-induced JNK phosphorylation, without affecting ERK or P38 phosphorylation. Neither AS-IV nor FA alone had any effect on the cells. CONCLUSIONS AND IMPLICATIONS: AS-IV synergizes with FA to alleviate renal tubulointerstitial fibrosis; this was associated with inhibition of tubular epithelial-mesenchymal transdifferentiation (EMT) and fibroblast activation, as well as an increase in NO production in the kidney.


Assuntos
Ácidos Cumáricos/farmacologia , Nefrite Intersticial/prevenção & controle , Saponinas/farmacologia , Triterpenos/farmacologia , Obstrução Ureteral/complicações , Animais , Transdiferenciação Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose/prevenção & controle , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Masculino , Nefrite Intersticial/etiologia , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar
20.
Braz. j. med. biol. res ; 42(12): 1173-1178, Dec. 2009. tab, ilus
Artigo em Inglês | LILACS | ID: lil-532296

RESUMO

This study was designed to investigate the effect of curcumin (diferuloylmethane) on the proliferation and apoptosis of hepatic stellate cells (HSC). The cell line HSC-T6 (1.25 x 10(5) cells/mL) was incubated with curcumin and HSC proliferation was detected by a methyl thiazolyl tetrazolium colorimetric assay. HSC apoptosis was detected by flow cytometry, transmission electron microscope and agarose gel electrophoresis. HSC proliferation was significantly inhibited in a concentration-dependent manner (10.6 to 63.5 percent) after incubation with 20-100 ìM curcumin, compared with a control group. At 20, 40, and 60 ìM, after 24 h of incubation, curcumin was associated with a significant increase in the number of HSC in the G2/M phase, and a significant decrease in cell numbers in the S phase (P < 0.05). At these concentrations, curcumin was also associated with an increase in the apoptosis index of 15.3 ± 1.9, 26.7 ± 2.8, and 37.6 ± 4.4 percent, respectively, compared to control (1.9 ± 0.6 percent, P < 0.01). At 40 ìM, the curcumin-induced apoptosis index at 12, 24, 36, and 48 h of incubation was 12.0 ± 2.4, 26.7 ± 3.5, 33.8 ± 1.8, and 49.3 ± 1.6 percent, respectively (P < 0.01). In conclusion, curcumin inhibits the in vitro proliferation of HSCs in the G2/M phase of the cell cycle and also induces apoptosis in a concentration- and time-dependent manner. The in vivo effect of curcumin on HSCs requires further investigation.


Assuntos
Animais , Ratos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Linhagem Celular , Colorimetria , Eletroforese em Gel de Ágar , Citometria de Fluxo , Células Estreladas do Fígado/patologia , Microscopia Eletrônica de Transmissão , Fatores de Tempo
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