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1.
Plant Dis ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157103

RESUMO

Soil-borne plant-pathogenic Phytopythium spp. can cause root rot and damping off on important plant species, resulting in serious economic loss. A survey in October 2021 identified soil-borne diseases occurring on Macadamia integrifolia in Yunnan Province, China. Microbes were isolated from necrotic roots of 23 trees with root rot symptoms by growing on cornmeal-based oomycete-selective 3P (Haas 1964) and P5APR (Jeffers and Martin, 1986) media at 24ºC in the dark for 7 days. Of the 56 single-hyphal isolates obtained, 18 were morphologically similar to Phytopythium vexans (van der Plaats-Niterink 1981; de Cock et al. 2015). Isolates LC04 and LC051 were selected for molecular analyses. The internal transcribed spacer (ITS) region and the cytochrome c oxidase subunit II (CoxII) gene were PCR-amplified using universal primers ITS1/ITS4 (White et al. 1990) and oomycete-specific primers Cox2-F/Cox2-RC4 (Choi et al. 2015), respectively. The PCR products were sequenced with the amplification primers and sequences were lodged in Genbank (Accession no. OM346742, OM415989 for ITS, OM453644, OM453643 for CoxII for isolates LC04 and LC051, respectively). The top BLAST hit in the Genbank nr database for all four sequences was Phytopythium vexans (>99% identity). A maximum-likelihood phylogenetic tree was constructed with analogous concatenated ITS and CoxII sequences from either type or voucher specimens of 13 Phytopythium species in the same phylogenetic clade as P. vexans (Table 1; Bala et. al 2010). Isolates LC04 and LC051 grouped most closely to P. vexans, with LC051 basal and sister to LC04 and P. vexans voucher specimen CBS119.80 with 100% support (Fig. 1). Millet seed inoculated with agar pieces colonized by P. vexans LC04 and LC51 was used to fulfill Koch's postulates (Li et al. 2015) in a completely randomized experimental design. Four 6-month-old M. integrifolia var. Keaau (660) seedlings were transplanted into pasteurized commercial potting mix containing 0.5% (w/w) inoculum. Plants were grown in free draining pots and watered once a day. At 14 days post-inoculation, roots were discolored compared to control plants inoculated with millet seed mixed with agar plugs lacking P. vexans (Fig. 2). By 30 days post-inoculation, infected roots were discolored with obvious decay and reduction in root system size. Control plants were symptomless. P. vexans was successfully re-isolated from two lesioned roots from each plant. The infection experiment was done twice, demonstrating that P. vexans LC04 and LC51 caused root disease on M. integrifolia. P. vexans causes root rot, damping-off, crown rot, stem rot or patch canker on economically important trees in many parts of the world, including seven plant species in China (Farr and Rossman 2022). This is the first report of pathogenic P. vexans on M. integrifolia in China. Reports of pathogenic P. vexans on multiple hosts in several parts of the world suggest it should be considered a quarantine risk and included in risk mitigation or pest management plans that include other species of Phytopythium, or species of Pythium or Phytophthora, to which P. vexans has many similarities (de Cock et al. 2015).

2.
Plant Dis ; 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35612578

RESUMO

The macadamia industry is developing rapidly in China. A brown leaf spot disease was noted in six Macadamia integrifolia plantations in Lincang, Yunnan, in October 2021. Over 60% of trees sampled had brown leaf spot symptoms, among approx.15,000 trees planted in these areas. Lesions (3 to 5 mm dia.) were small round brown spots with yellow edges. Lesions on severely infected leaves were darker and larger, with irregular shape (8 to 10 mm long, 3 to 6 mm wide). About 10% of diseased leaves had lesions characterized by a shot hole surrounded by a yellow halo. Potential pathogens were isolated from four randomly-selected symptomatic leaves from each of the six plantations by cutting lesion edges into small pieces. The pieces were surface sterilized, placed onto water agar containing 100 ppm aureomycin and incubated for 5 days at 24°C in the dark. Subculturing microbial growth on potato dextrose agar produced single-hyphal isolates with white fluffy aerial mycelia that turned pale olivaceous gray after 4 to 5 days. In four randomly-selected cultures, conidia were single celled, hyaline, spindle shaped to oval, and measured 10.9 to 16.3 µm long and 4.0 to 6.2 µm wide (n = 50). These characteristics matched those of Neofusicoccum parvum (Pavlic et al. 2009). Isolate LC013 was randomly selected as a representative individual for molecular identification. Internal transcribed spacer (ITS; ITS1/ITS4 primers; White et al. 1990), beta-tubulin gene (tub2; BT2A/BT2B primers; Glass and Donaldson 1995) and translation elongation factor 1-alpha gene (tef1-α; EF1-728F/EF2 primers; Carbone and Kohn 1999; O'Donnell et al. 1998) regions were PCR amplified from genomic DNA. Sequences of the products were used to BLAST probe the type specimen nucleotide sequences in GenBank. The LC013 sequences (GenBank accessions OM392021 (ITS); OM453641 (tub2); OM567656 (tef1-α)) had >99% sequence identity with analogous sequences from the type specimen of N. parvum CBS 138823 (accessions AY236943 (ITS); AY236917 (tub2); AY236888 (tef1-α)). Isolate LC013 was sister to N. parvum type strain in a maximum-likelihood (ML) tree constructed from analogous concatenated ITS, tef1-α, and tub2 sequences of 27 species that are phylogenetically closely-related to LC013 based on the ITS single locus ML tree. Koch's postulates were tested twice with two isolates by wounding leaves of four 14-month-old M. integrifolia seedlings with a sterile needle and placing a 5-mm-diameter agar plug containing N. parvum on the wound site. PDA plugs alone were used as uninoculated controls. Leaves were covered with sealed bags to maintain >90% humidity for 24 hours. All plants were kept in the same glasshouse under natural conditions. Leaves of inoculated plants began to discolor at 5 days post-inoculation (dpi). Brown spot symptoms were observed at 9 dpi. Control plants were symptomless. N. parvum was re-isolated from leaf lesions of the infected plants, but not from control plants, thus fulfilling Koch's postulates. N. parvum is an aggressive pathogen that causes severe disease on important tree and woody species, including M. integrifolia (Liddle et al. 2019). In China, it has been reported to cause leaf spot disease on 26 plant species (Farr and Rossman 2022), but this is the first report of N. parvum causing leaf spot disease on M. integrifolia. Further investigation is required to estimate the importance of this pathogen to the macadamia industry in China.

3.
Zhonghua Yi Shi Za Zhi ; 43(4): 222-5, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24345548

RESUMO

Safety culture is the culture of all the connotations to a safe direction for the purpose of advancing a unified organizational behavior. Safety culture was first introduced to the field of medicine by the American researchers in the 1990s. Subsequently, researchers from different countries initiated the relevant studies and put forward five subcultures of patient safety culture. At present, the patient safety culture research is mainly conducted in the United States, China and the UK of which cross-sectional studies are the most popular study designs including the evaluation of patient safety scale, reliability and validity analysis. Non-sectional studies are focused on the study of subcultures including leadership, communication, cooperation and reports. Compared with the studies abroad, the studies on patient safety culture in China are rather late, yet also mainly on reliability and validity analysis of scales. Most participants we investigated are nurses from teaching hospitals. But in the real healthcare situation, fostering a positive safety culture is still very lacking and many ideas and behaviors are in the state of traditional blaming culture.

4.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(4): 377-81, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22539386

RESUMO

OBJECTIVE: To evaluate the benefit and safety of fluorouracil implants on colorectal cancer. METHODS: Based on the methods of Cochrane systematic reviews, databases including CBM(1982 to March 2011), CNKI(1911 to March 2011), EMBASE(1966 to March 2011), and Medline(1950 to March 2011) were searched to identify randomized controlled trials assessing the benefit of fluorouracil implants on colorectal cancer. The quality of the included studies was assessed using the Cochrane's tool for assessing bias. RevMan5.0 was used for meta-analysis. RESULTS: Sixteen studies were included(n=1223). The quality of included studies was moderate. Fluorouracil implants could reduce the 2-year mortality(RR=0.33. 95% CI:0.18-0.59), 2-year metastasis rate(RR=0.35, 95% CI: 0.19-0.66), and 2-year recurrence rate(RR=0.48, 95% CI:0.36-0.65). There were no significant differences in complications and adverse effects between fluorouracil implants and the control group. CONCLUSIONS: Current evidence demonstrates that fluorouracil implants may modestly improve the outcome of colorectal cancer patients without increasing its adverse events. However, the results should be interpreted with caution due to the risk of bias of included studies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
J Evid Based Med ; 5(4): 216-25, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23557502

RESUMO

OBJECTIVE: Injection of brucea javanica oil emulsion (IBJOE), one of Chinese patent drugs has been widely used for lung cancer (LC) in China, and is known to provide some favorable outcomes, in particular when it combined with conventional treatment. However, little available best evidence is known about its effect and safety. This paper aims to evaluate the effectiveness and safety of IBJOE plus chemoradiotherapy to alleviate symptoms of LC patients. METHODS: A complete literature searching was conducted in databases including Chinese Biomedical Literature Database, China Academic Journals Full-text Database, Chinese Scientific Journals Database, the Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE to identify randomized controlled trials (RCTs) of IBJOE with chemoradiotherapy versus chemoradiotherapy alone for LC patients regardless of blinding, duration of treatment or duration of follow-up. All searching dates were from the beginning to December 2011. Quality of the included studies was assessed using the method by Cochrane Reviewer Handbook, and data analysis was performed using RevMan 5.10 software developed by The Cochrane Collaboration. RESULTS: The searching yielded over 1371 relevant citations, most of which did not meet the inclusion criteria. Finally, only 21 RCTs involving 1619 patients were included, and all the studies were of poor quality. Pooled analyses were performed to reveal that compared with chemoradiotherapy alone, IBJOE plus chemoradiotherapy had a better complete response rate (relative risk (RR) = 1.42; 95% CI 1.05 to 1.92; P = 0.02) and improved quality of life (RR = 1.83; 95% CI 1.63 to 2.07; P < 0.00001) measured by Karnofsky Performance Status scale. In addition, there was a significant difference on the outcome of long-term survival rate, level of immune function, and some incidences of adverse effects. CONCLUSIONS: IBJOE plus chemoradiotherapy may have positive effects on LC patients in response rate, improvement of quality of life, and reducing incidences of some adverse effects compared with chemoradiotherapy alone. However, the results need to be viewed with caution because of low quality of the included studies.


Assuntos
Brucea , Quimiorradioterapia Adjuvante , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/terapia , Fitoterapia , Óleos de Plantas/uso terapêutico , Emulsões , Humanos , Injeções Intravenosas , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
Mol Biol Rep ; 37(7): 3407-12, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20012371

RESUMO

The anti-proliferative, cytotoxic and apoptogenic activities of delisheng, a Chinese medicinal compound, has been investigated. In this study, the hepatocarcinoma cell line (HepG2) and the liver cell line (L-02) were exposed to delisheng (6.25, 50 and 100 µl/ml). Delisheng suppressed the proliferation and viability of normal liver L-02 cells slightly, but strongly inhibited the proliferation and viability of hepatocarcinoma HepG2 cells. The flow cytometric analysis of HepG2 cells demonstrated that delisheng primarily arrested the HepG2 cells at the G1 phase of the cell cycle. Annexin V-FITC/PI staining corroborates the apoptogenic nature of delisheng on HepG2 cells. The anti-proliferative and pro-apoptotic effect of delisheng in HepG2 cells was associated with changes in the Bcl-2/Bax ratio and the induction of caspase-mediated apoptosis. Upregulation of DR5 expression was observed in HepG2 cells after treatment with delisheng. The findings from the present study suggest that delisheng has selective cytotoxic activities against HepG2 cells. Delisheng triggered time- and dose-dependent apoptosis in HepG2 cells by activating the mitochondria-mediated and death receptor-mediated apoptotic pathways.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Anexina A5/metabolismo , Western Blotting , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/metabolismo , Células Hep G2 , Humanos , Propídio/metabolismo , Receptores de Morte Celular/metabolismo , Proteína X Associada a bcl-2/metabolismo
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