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1.
Front Cell Infect Microbiol ; 11: 728929, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804990

RESUMO

Pulsatilla chinensis (Bunge) Regel is a commonly used Chinese medicine for clearing away heat and detoxification, cooling blood, stopping dysentery, and anti-inflammatory effects. Pulsatilla chinensis saponins (PRS) have been identified to be responsible for producing these pharmacological activities. Studies have shown that Pulsatilla decoction has a good therapeutic effect on ulcerative colitis (UC), however, the therapeutic effect of PRS on UC has not been reported. Therefore, the purpose of this study was to investigate the possible anti-UC activity of PRS using a dextran sulfate sodium (DSS)-induced rat model, and further study the mechanism of PRS in the treatment of UC. The fecal and colon samples were collected from rats to monitor the changes in the composition and diversity of the intestinal flora, and pathological colon sections were also made to examine the mesenteric hemorheological characteristics. The results showed that PRS significantly reduced the mesenteric blood flow in UC rats and significantly alleviated the inflammatory response, which indicates that saponins are involved in the anti-UC effects of PRS. At the same time, it is also suggested that the regulation of intestinal flora by Pulsatilla chinensis saponins is an important pathway for its anti-UC activity, which may be ascribed to the increase in beneficial bacteria like norank_F_Muribaculaceae and norank_F_norank_O_Clostridia_UCG-014, and decrease in the harmful Bacteroides.

2.
Acta Pharm Sin B ; 11(10): 3150-3164, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34729306

RESUMO

The three-dimensional (3D) conformation of chromatin is integral to the precise regulation of gene expression. The 3D genome and genomic variations in non-alcoholic fatty liver disease (NAFLD) are largely unknown, despite their key roles in cellular function and physiological processes. High-throughput chromosome conformation capture (Hi-C), Nanopore sequencing, and RNA-sequencing (RNA-seq) assays were performed on the liver of normal and NAFLD mice. A high-resolution 3D chromatin interaction map was generated to examine different 3D genome hierarchies including A/B compartments, topologically associated domains (TADs), and chromatin loops by Hi-C, and whole genome sequencing identifying structural variations (SVs) and copy number variations (CNVs) by Nanopore sequencing. We identified variations in thousands of regions across the genome with respect to 3D chromatin organization and genomic rearrangements, between normal and NAFLD mice, and revealed gene dysregulation frequently accompanied by these variations. Candidate target genes were identified in NAFLD, impacted by genetic rearrangements and spatial organization disruption. Our data provide a high-resolution 3D genome interaction resource for NAFLD investigations, revealed the relationship among genetic rearrangements, spatial organization disruption, and gene regulation, and identified candidate genes associated with these variations implicated in the pathogenesis of NAFLD. The newly findings offer insights into novel mechanisms of NAFLD pathogenesis and can provide a new conceptual framework for NAFLD therapy.

4.
Bioengineered ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783631

RESUMO

Chemotherapy is a traditional treatment method in clinical cancer treatment. However, it is limited due to the large toxic side effects of chemotherapeutics. Nanomedicines have shown great potential in the application of tumor therapy. The size of nanoparticles as a crucial factor in the enhanced permeability and retention (EPR) effect can be regulated for the enhanced chemotherapy. Therefore, we believe that regulation of nanoparticle size can be used as an effective sensitizer to enhance the therapeutic effect of chemotherapy drugs on tumors. Here, we prepared several nanoparticles of different hydrodynamic diameters commonly found in nanomedical applications by the diblock copolymer of methoxy polyethylene glycol- poly (ϵ-caprolactone) (mPEG-PCL). The blood circulation effect and organ distribution in blood were detected by fluorescence labeled nanoparticles. We found that the small-sized nanoparticles exhibited much longer blood circulation time than the large-sized nanoparticles in vivo, and thus the nanoparticle concentration in the tumor tissue was relatively high. Systematic injection of the doxorubicin (DOX) loaded nanoparticles can effectively inhibit tumor growth. Compared to the free drug, tumor cells were much more sensitive to DOX loaded nanoparticles of small size. Our nano-drug delivery system has been proven to be safe and non-toxic in vivo and was suitable for use as a sensitizer in clinical oncology chemotherapy.

5.
Nat Commun ; 12(1): 6340, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732714

RESUMO

Despite radiation forming the curative backbone of over 50% of malignancies, there are no genomically-driven radiosensitizers for clinical use. Herein we perform in vivo shRNA screening to identify targets generally associated with radiation response as well as those exhibiting a genomic dependency. This identifies the histone acetyltransferases CREBBP/EP300 as a target for radiosensitization in combination with radiation in cognate mutant tumors. Further in vitro and in vivo studies confirm this phenomenon to be due to repression of homologous recombination following DNA damage and reproducible using chemical inhibition of histone acetyltransferase (HAT), but not bromodomain function. Selected mutations in CREBBP lead to a hyperacetylated state that increases CBP and BRCA1 acetylation, representing a gain of function targeted by HAT inhibition. Additionally, mutations in CREBBP/EP300 are associated with recurrence following radiation in squamous cell carcinoma cohorts. These findings provide both a mechanism of resistance and the potential for genomically-driven treatment.

6.
Biochem Genet ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34762200

RESUMO

The literature has provided inconsistent findings on the relationship between interleukin IL-1 gene polymorphisms and susceptibility to ankylosing spondylitis (AS). Therefore, a systematic review and meta-analysis were conducted. Online electronic database searches were performed for relevant research published as of May 2021. Meta-analysis was performed to compare alleles and multiple genetic models (including dominant, recessive, heterozygous, and homozygous models) using random-effects models to reduce the impact of heterogeneity. A 95% confidence interval (95% CI) odds ratio (OR) was used to assess potential relationships. Nineteen studies including 6235 patients with AS and 5919 healthy controls were recruited. IL-1A-889 (rs1800587) had statistical significance in the allelic model (OR 1.38, 95% CI 1.08-1.77, P = 0.010) (I2 = 51%.1, P = 0.0001); homozygous model (OR 1.92, 95% CI 1.27-2.89, P = 0.002); heterozygous model (OR 1.49, 95% CI 1.02-2.17, P = 0.163); dominant genetic model (OR 1.53, 95% CI 1.05-2.24, P = 0.026); and recessive model (OR 1.54, 95% CI 1.04-2.28, P = 0.031). Further stratified analysis showed that the allele model (OR 1.35, 95% CI 1.08-1.69, P = 0.008), heterozygous model (OR 1.45, 95% CI 1.07-1.96, P = 0.017), and dominant model (OR 1.49, 95% CI 1.11-1.99, P = 0.007) in the English population and allele model (OR 2.21, 95% CI 1.45-3.37, P = 0.0001), homozygous model (OR 3.85, 95% CI 1.38-10.76, P = 0.010), heterozygous model (OR 3.42, 95% CI 1.85-6.32, P = 0.0001), and dominant model (OR 3.49, 95% CI 1.93-6.30, P = 0.001) in Tunis were significantly associated with susceptibility to AS. Analysis of the IL1F7 exon 2 (rs3811047) showed that the G allele frequency was higher in the normal population than in the AS population (OR 0.76, 95% CI (0.64, 0.91)). Further stratified analysis concluded that the allele model was significantly associated with AS susceptibility in Canadian (OR 0.76, 95% CI 0.61-0.94, P = 0.011) and Chinese patients (OR 0.64, 95% CI 0.41-0.98, P = 0.041). The meta-analysis showed that the IL-1 gene polymorphism IL-1A-889 (rs1800587) increases the risk of AS in English and Tunisian populations. IL1F7 exon 2 (rs3811047) is negatively correlated with susceptibility to AS in Canadian and Chinese populations, but additional studies are needed for further exploration.

7.
ACS Med Chem Lett ; 12(10): 1589-1595, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34676041

RESUMO

Honokiol (HK) has antiproliferation effects against numerous cancer cells, but its low solubility and bioavailability impede its application. In this study, a prodrug of HK (HP) featuring a maleimide group was synthesized and then mixed with tocopherol polyethylene glycol succinate to prepare prodrug nanoparticles (HP-NPs). In vitro albumin binding experiments showed that HP rapidly reacted with the cysteine thiols of albumin to form a covalent conjugate that released HK slowly in the LLC tumor cell line. In vitro cell apoptosis and uptake assays showed that the cellular uptake of the HK increased into the LLC cells as the albumin concentration increased. Strikingly, in vivo pharmacokinetics and pharmacodynamics measurements demonstrated that the HP-NPs significantly prolonged the circulation and increased tumor accumulation. Taken together, our study demonstrated, both in vitro and in vivo, that the albumin-based HP-NPs delivery system holds significant potential toward the treatment of lung cancer in clinical studies.

8.
Acta Pharmacol Sin ; 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654876

RESUMO

Transient receptor potential channel TRPV4 and nicotinamide adenine dinucleotide phosphate oxidase (Nox2) are involved in oxidative stress that increases endothelial permeability. It has been shown that obesity enhances the physical association of TRPV4 and Nox2, but the role of TRPV4-Nox2 association in obesity has not been clarified. In this study we investigated the function of TRPV4-Nox2 complex in reducing oxidative stress and regulating abnormal vascular permeability in obesity. Obesity was induced in mice by feeding a high-fat diet (HFD) for 14 weeks. The physical interaction between TRPV4 and Nox2 was measured using FRET, co-immunoprecipitation and GST pull-down assays. The functional interaction was measured by rhodamine phalloidin, CM-H2DCFDA in vitro, the fluorescent dye dihydroethidium (DHE) staining assay, and the Evans blue permeability assay in vivo. We demonstrated that TRPV4 physically and functionally associated with Nox2, and this physical association was enhanced in aorta of obese mice. Furthermore, we showed that interrupting TRPV4-Nox2 coupling by TRPV4 knockout, or by treatment with a specific Nox2 inhibitor Nox2 dstat or a specific TRPV4 inhibitor HC067046 significantly attenuated obesity-induced ROS overproduction in aortic endothelial cells, and reversed the abnormal endothelial cytoskeletal structure. In order to discover small molecules disrupting the over-coupling of TPRV4 and Nox2 in obesity, we performed molecular docking analysis and found that compound M12 modulated TRPV4-Nox2 association, reduced ROS production, and finally reversed disruption of the vascular barrier in obesity. Together, this study, for the first time, provides evidence for the TRPV4 physically interacting with Nox2. TRPV4-Nox2 complex is a potential drug target in improving oxidative stress and disruption of the vascular barrier in obesity. Compound M12 targeting TRPV4-Nox2 complex can improve vascular barrier function in obesity.

9.
Front Public Health ; 9: 752530, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604168

RESUMO

Under the context of rapid economic and social development, and growing demands for a better life, Chinese residents have been increasingly concerned with their health status and issues. In this study, the internal relations between the purchase of commercial insurance by residents and their health status are analyzed and studied with a polytomous logit model based on the data of Chinese General Social Survey (CGSS) in 2015. According to the research result, purchase of commercial insurance significantly improved the health status of residents, with an improving effect for rural residents apparently better than that among urban residents. In addition, purchase of commercial insurance can promote the health status of residents by increasing their household income. This research will provide an effective reference for the innovative development and medical reform of the commercial insurance of China in the future, which is theoretically and practically significant to the implementation of the Healthy China Strategy.


Assuntos
Nível de Saúde , População Rural , China , Humanos , Seguro Saúde , Modelos Logísticos
10.
ACS Appl Mater Interfaces ; 13(42): 50246-50257, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637262

RESUMO

Hypoxia, induced by inadequate oxygen supply, is a key indication of various major illnesses, which necessitates the need to develop new nanoprobes capable of sensing hypoxia environments for the targeted system monitoring and drug delivery. Herein, we report a hypoxia-responsive, periodic mesoporous organosilica (PMO) nanocarrier for repairing hypoxia damage. ß-cyclodextrin (ß-CD) capped azobenzene functionalization on the PMO surface could be effectively cleaved by azoreductase under a hypoxia environment. Moreover, the nanosystem is equipped with fluorescence resonance energy transfer (FRET) pair (tetrastyrene derivative (TPE) covalently attached to the PMO framework as the donor and Rhodamine B (RhB) in the mesopores as the receptor) for intracellular visualization and tracking of drug release in real-time. The design of intelligent nanocarriers capable of simultaneous reporting and treating of hypoxia conditions highlights a great potential in the biomedical domain.

11.
J Exp Bot ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34610119

RESUMO

Rice polluted by metal(loid)s, especially arsenic (As) and cadmium (Cd), imposes serious health risks. Numerous studies have demonstrated that the obligate plant symbionts arbuscular mycorrhizal fungi (AMF) can reduce As and Cd concentrations in rice. The behaviours of metal(loid)s in the soil-rice-AMF system are of significant interest for scientists in the fields of plant biology, microbiology, agriculture, and environmental science. This paper reviews the mechanisms of As and Cd accumulation in rice with and without the involvement of AMF. In the context of the rice-soil-AMF system, we review and discuss the role of AMF in affecting soil ion mobility, chemical form, transport pathways (including symplast and apoplast), and genotype variation. A potential strategy for AMF application in rice fields is considered, followed by future research directions to improve theoretical understanding and encourage field application.

12.
J Org Chem ; 86(21): 15640-15647, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34672589

RESUMO

A one-pot, two-step protocol for the synthesis of libraries of remarkable functionalized sulfone analogues of 9b,10,10a,10b-tetrahydro-1H-cyclopropa[c][1,4]thiazino[4,3-a]quinolines is described. A class of various functionalized molecular skeletons was obtained by cyclopropanation of quinolinium zwitterionic thiolates. The reaction pathway involves the formation of a [2 + 1] cycloaddition intermediate followed by a [5 + 1] cycloaddition.

13.
Nat Biomed Eng ; 5(10): 1189-1201, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34608279

RESUMO

The early stages of progressive degeneration of cartilage in articular joints are a hallmark of osteoarthritis. Healthy cartilage is lubricated by brush-like cartilage-binding nanofibres with a hyaluronan backbone and two key side chains (lubricin and lipid). Here, we show that hyaluronan backbones grafted with lubricin-like sulfonate-rich polymers or with lipid-like phosphocholine-rich polymers together enhance cartilage regeneration in a rat model of early osteoarthritis. These biomimetic brush-like nanofibres show a high affinity for cartilage proteins, form a lubrication layer on the cartilage surface and efficiently lubricate damaged human cartilage, lowering its friction coefficient to the low levels typical of native cartilage. Intra-articular injection of the two types of nanofibre into rats with surgically induced osteoarthritic joints led to cartilage regeneration and to the abrogation of osteoarthritis within 8 weeks. Biocompatible injectable lubricants that facilitate cartilage regeneration may offer a translational strategy for the treatment of early osteoarthritis.

14.
Analyst ; 146(22): 6788-6797, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34671790

RESUMO

The production of excess free zinc ions (Zn2+) in cells has been identified as an important cause of cell injury or apoptosis after ischemia reperfusion. Thus, developing a nanosystem with multiple therapeutic functions to significantly eliminate multiple cell injury factors is of great interest. Here, a super-assembled nanosystem consisting of a polyethylene glycol (PEG) surface-modified mesoporous silica nanoparticle (MSN) encapsulating 2-methylimidazole (2MI) and a Zn2+ probe (PZn) was fabricated. The 2MI-P@MSN nanoassemblies showed a "turn-on" fluorescence signal at 476 nm toward zinc ions due to the presence of PZn. Besides, zeolitic imidazolate framework-8 (ZIF-8) could be assembled on the site intracellularly after 2MI chelating with free zinc ions. The experimental results revealed that 2MI-P@MSN exhibited excellent biocompatibility and non-cytotoxicity, and was able to provide satisfactory protection to OGD/R-treated cells based on zinc ion adsorption and the antioxidant effect of ZIF-8, which could effectively improve the survival rate of reperfusion injury cells from 52% to 73%. Notably, selective and quantitative sensing of Zn2+ was successfully carried out in the cells. This strategy highlights the potential of the detection, absorption and assembly of excess zinc ions simultaneously for cell therapy, which provides a promising therapeutic method for ischemic stroke, oxidative damage and diseases associated with zinc ion accumulation.


Assuntos
Traumatismo por Reperfusão , Dióxido de Silício , Cristalização , Humanos , Reperfusão , Zinco
15.
Int J Clin Exp Pathol ; 14(8): 918-919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527136

RESUMO

[This corrects the article on p. 5175 in vol. 8, PMID: 26191214.].

16.
Nutr J ; 20(1): 74, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479555

RESUMO

BACKGROUND: The effect of the overall diet quality on cardiometabolic diseases has been well studied in the Western population. However, evidence is still in need regarding dietary patterns depicting unique Chinese dietary habits and their associations with cardiometabolic diseases. METHODS: A prospective cohort recruited around 0.5 million Chinese residents aged 30-79 years from 10 diverse survey sites during 2004-08. Dietary patterns were obtained using factor analysis based on the habitual consumption of 12 food groups collected at baseline. Among 477,465 eligible participants free of prior heart disease, stroke and cancer, linkages to multiple registries and health insurance database recorded 137,715 cardiovascular diseases (CVD) and 17,412 diabetes cases (among 451,846 non-diabetic participants) until 31 December 2017. Adjusted hazard ratios (HRs) were estimated to compare the risks of cardiometabolic diseases across quintiles of dietary pattern scores using the Cox regression. RESULTS: Two dietary patterns were derived: the traditional northern pattern, characterised by wheat, other staples, egg and dairy products; and the modern pattern, featured with fresh fruit, meat, poultry, fish, dairy products and soybean. Adherence to either dietary pattern was associated with lower risks of major cardiometabolic diseases in a dose-response relationship way. After multivariate adjustment, participants adhering to the traditional northern pattern the most had an 8% (95%CI: 5-11%) lower risk of CVD in comparison with those adhering the least. Corresponding risk reductions were 12% (11-32%) for haemorrhagic stroke (HS), 14% (8-19%) for ischaemic stroke (IS), and 15% (6-24%) for diabetes, respectively. When comparing extreme quintiles of the modern pattern, the adjusted HR of HS was 0.67 (95%CI: 0.59-0.77). Corresponding HRs were 0.89 (0.86-0.92) for CVD, 0.88 (0.77-0.99) for MCE, 0.85 (0.80-0.89) for IS, and 0.89 (0.81, 0.97) for diabetes. CONCLUSION: Among Chinese adults, both traditional northern and modern dietary patterns were associated with lower risks of cardiovascular disease and diabetes beyond other risk factors.


Assuntos
Isquemia Encefálica , Doenças Cardiovasculares , Acidente Vascular Cerebral , Adulto , Animais , Doenças Cardiovasculares/epidemiologia , China/epidemiologia , Estudos de Coortes , Dieta , Humanos , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
17.
J Environ Manage ; 300: 113745, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34547575

RESUMO

A large amount of waste activated sludge (WAS) and food waste (FW) are produced every year in China. Anaerobic co-digestion is considered to be an effective way to solve this problem. This study applied FW/WAS mixture as co-substrate to create different digestive environment, aiming to understand the mechanism of Fe3O4 particles in promoting AD performance. The results showed that the addition of Fe3O4 presented various performances when facing different digestive acidification stress brought by different mixing ratios of WAS and FW. Methanogenic pathways and microbial communities varied with substrates' properties. For group A (WAS mono-digestion), the acetoclastic methanogens dominated, 20 mg/g VS (according to the iron element) Fe3O4 could promote methane production, while 200 mg/g VS Fe3O4 would inhibit microbial activity. The promoted methane production by Fe3O4 was attributable to the promotion of sludge hydrolysis. For group B (WAS: FW = 1:0.5, based on VS addition, similarly hereinafter), Fe3O4 triggered direct interspecific electron transfer (DIET) between bacteria and methanogens. For group C (WAS: FW = 1:1), the hydrogenotrophic methanogens dominated, bacteria excreted more non-conductive polysaccharides in EPS to resist unfavorable environment, thereby it prevented their contact with Fe3O4 particles. So, it was difficult for Fe3O4 to trigger DIET and promote the digestive performance of batch experiments in such condition.


Assuntos
Eliminação de Resíduos , Esgotos , Anaerobiose , Reatores Biológicos , Digestão , Alimentos , Metano
18.
Plant Dis ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515503

RESUMO

Bletilla striata (Thunb.) Rchb. f. (Orchidaceae family, known as Baiji in Chinese) is a perennial herb and has been traditionally used for hemostasis and detumescence in China. In April of 2020, a leaf spot disease on B. striata was observed in plant nurseries (∼0.2 h) in Guilin, Guangxi Province, China. Approximately 20% of the plants were symptomatic, of which 150 plants were randomly selected for investigation. Initial symptoms include the appearance of small, circular or irregular light brown spots, randomly scattered on the edges and surfaces of the leaves, which progressively expand into large, suborbicular or irregular-shaped dark brown, necrotic areas. At the severe stage, the lesions coalesced into large necrotic areas and ultimately resulted in leaf abscission. To isolate the pathogen, three representative plants exhibiting symptoms were collected from the nurseries. Leaf tissues (5 × 5 mm) were cut from the margin of necrotic lesions (n = 18), surface-disinfected in 1% sodium hypochlorite (NaOCl) solution for 2 min, then rinsed three times in sterile water before isolation. The tissues were plated on potato dextrose agar (PDA) medium, and incubated at 28°C (12-h photoperiod) for 3 days. Hyphal tips from recently germinated spores were transferred to PDA to obtain pure cultures. Nine fungal isolates with similar morphological characteristics were obtained. Three single-spore isolates, BJ23.1, BJ55.1, and BJ91.3, were subjected to further morphological and molecular characterisation. Colonies on PDA plates were villose, had a dense growth of aerial mycelia and appeared white (1A1) to yellowish white (3A2). Macroconidia were smooth, hyaline, straight to slightly curved, usually contained three or five septa, and measuring 23.3 to 42.1 × 3.0 to 6.2 µm (mean ± SD: 31.2 ± 5.1 × 4.2 ± 0.6 µm, n = 50). Microconidia were generally cylindrical, straight to slightly curved, aseptate, and measuring 7.2 to 18.8 × 2.5 to 4.3 µm (mean ± SD: 12.1 ± 2.8 × 3.3 ± 0.5 µm, n = 62). Morphological characteristics are similar to those of F. commune (Skovgaard et al. 2003). For molecular identification, the genomic DNA of the isolates BJ23.1, BJ55.1, and BJ91.3 were extracted using the CTAB method (Guo et al. 2000). The internal transcribed spacer (ITS) region of rDNA, partial translation elongation factor-1 alpha (TEF-1α), RNA polymerase second largest subunit (RPB2), and the mitochondrial small subunit rDNA (mtSSU) genes were amplified using primer pairs [ITS1/ITS4 (White et al. 1990), EF-1/EF-2 (O'Donnell et al. 1998), and 5f2/11ar (Liu et al. 1999, Reeb et al. 2004), MS1/MS2 (Li et al. 1994), respectively]. The obtained sequences were deposited in NCBI GenBank under the following accession numbers: ITS (MZ424697 to MZ424699), TEF-1α (MZ513467 to MZ513469), RPB2 (MZ513473 to MZ513475), and mtSSU (MZ513470 to MZ513472). BLAST® analysis of the deposited sequences showed 99 to 100% identity with those of F. commune present in GenBank (Accession numbers: DQ016205, MH582348, MH582181, AF077383). In addition, a phylogenetic analysis using concatenated sequences of ITS, TEF-1α, mtSSU genes showed that BJ23.1, BJ55.1, and BJ91.3 located on the same clade with strains of F. commune. Therefore, based on morphological and molecular characteristics, the isolates were identified as F. commune (Skovgaard et al. 2003, Stewart et al. 2006). Pathogenicity was tested using 1.5-year-old B. striata plants. Healthy leaves on plants were inoculated with 5 × 5 mm mycelial discs of strains BJ23.1, BJ55.1, and BJ91.3 from 3-day-old PDA cultures, each isolate was inoculated onto three plants; three other plants inoculated with sterile PDA discs served as controls. All plants were enclosed in transparent plastic bags and incubated in a greenhouse at 28°C for 14 days (12-h photoperiod). Three days post-inoculation, leaf spot symptoms appeared on the inoculated leaves. No symptoms were detected on control plants. Experiments were replicated three times with similar results. To fulfill Koch's postulates, F. commune was consistently re-isolated from symptomatic tissue and confirmed by morphology and sequencing, whereas no fungus was isolated from the control plants. F. commune has been reported to cause diseases on some plants, including sugarcane (Wang et al. 2018), maize (Xi et al. 2019) and Wax Gourd (Zeng et al. 2020). To our knowledge, this is the first report of F. commune causing leaf spot disease on B. striata in China. Identification of this pathogen provides the information for further studies to develop management strategies to control the disease.

19.
J Hazard Mater ; 416: 125894, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492832

RESUMO

The chemistry of root cell wall of rice could be changed by inoculation of arbuscular mycorrhizal fungi (AMF). Hydroponic experiments were conducted to investigate the roles of such changes on cadmium (Cd) uptake and distribution in rice. Results showed that inoculation of AM fungus Rhizophagus intraradices (RI) significantly enhanced (p < 0.05) shoot biomass, plant height and root length of rice, and decreased Cd concentration in shoot and root under Cd stress. Moreover, Cd in root was mainly found in pectin and hemicellulose 1 (HC1) components of root cell wall. Inoculation of RI increased the levels of pectin, HC1 and lignin content, accompanied by the increments of L-phenylalanine ammonia-lyase (PAL) and pectin methylesterase (PME) activities. Results of Fourier transform infrared spectroscopy further showed that more hydroxyl and carboxyl groups in root cell wall were observed in mycorrhizal treatment, compared with control. This study demonstrates that cell wall components could be the locations for Cd fixation, which reduced Cd transportation from root to shoot. Inoculation of AMF may remodel root cell wall biosynthesis and affect the characteristics of Cd fixation. The entering and fixing mechanisms should be further studied.


Assuntos
Micorrizas , Oryza , Poluentes do Solo , Cádmio/análise , Parede Celular/química , Fungos , Raízes de Plantas/química , Poluentes do Solo/análise
20.
Mater Horiz ; 8(11): 3082-3087, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34505616

RESUMO

Red-to-near-infrared (NIR) fluorophores are highly desirable in bio-imaging studies with advantages of high tissue penetration ability and less interference from auto-fluorescence. However, their preparation usually requires tedious synthetic procedures, which seriously restrict their applications. Thus, the direct preparation of red-to-NIR fluorophores from easily available substrates is highly desirable. Compared with the conventional closed-shell fluorophores, radical cations feature a large red-shift absorption, but only very few of them are fluorescent and they suffer from high instability. Herein, we proposed a convenient strategy for the preparation of red-to-NIR fluorophores through air oxidation of electron-rich 2,5-dimethylpyrroles to in situ generate red-to-NIR emissive radical cations, which can be stabilized by adsorption on silica gel-coated thin layer chromatography (TLC) plates or encapsulated in cucurbit[7]uril (CB[7]). The radical cations derived from pyrroles were verified using electron paramagnetic resonance (EPR) spectroscopy, theoretical calculations and one-electron oxidation experiments. Moreover, the pyrrole-derived radical cations encapsulated in CB[7] can be used for mitochondrial imaging in living cells with high specificity and in vivo imaging with long-term stability. The easily available pyrrole-derived radical cations with red-to-NIR emission are thus promising for biomedical applications.

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