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1.
Small ; 19(44): e2302197, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37403302

RESUMO

Synaptic devices that mimic biological synapses are considered as promising candidates for brain-inspired devices, offering the functionalities in neuromorphic computing. However, modulation of emerging optoelectronic synaptic devices has rarely been reported. Herein, a semiconductive ternary hybrid heterostructure is prepared with a D-D'-A configuration by introducing polyoxometalate (POM) as an additional electroactive donor (D') into a metalloviologen-based D-A framework. The obtained material features an unprecedented porous 8-connected bcu-net that accommodates nanoscale [α-SiW12 O40 ]4- counterions, displaying uncommon optoelectronic responses. Besides, the fabricated synaptic device based on this material can achieve dual-modulation of synaptic plasticity due to the synergetic effect of electron reservoir POM and photoinduced electron transfer. And it can successfully simulate learning and memory processes similar to those in biological systems. The result provides a facile and effective strategy to customize multi-modality artificial synapses in the field of crystal engineering, which opens a new direction for developing high-performance neuromorphic devices.

2.
Inorg Chem ; 62(48): 19706-19719, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37967369

RESUMO

Organic-inorganic hybrid iodobismuthate perovskites have become promising semiconductive materials for their environmentally friendly and light-harvesting characteristics. However, their low-dimensional bismuth-iodide skeletons result in poor charge-separation efficiency, limiting their application in optoelectronic devices. To address this issue, the donor-acceptor (D-A) heterostructures have been introduced to the iodobismuthate hybrid materials by incorporating an electron-deficient N,N'-bis(4-aminoethyl)-1,4,5,8-naphthalene diimide (NDIEA) as the electron acceptor and organic counterpart. Five naphthalenediimide/iodobismuthate hybrid heterostructures, named (H2NDIEA)1.5·Bi2I9·3DMF (1), H2NDIEA·[Bi2I8(DMF)2]·2DMF (2), (H2NDIEA)2·Bi4I16·2H2O·4MeOH (3), (H2NDIEA)2·Bi4I16·8H2O (4), and [(H2NDIEA)2·Bi6I22]n·4nH2O (5) (DMF = N,N-dimethylformamide), were synthesized. Their crystal structures, water stabilities, charge-separated behaviors, and electrical properties have been studied through experimental and computational investigations. The results revealed that hybrids 3-5 exhibited high water resistance attributed to their tightly packed structures and robust H-bonds between solvent molecules and organic-inorganic supramolecular frameworks. Density functional theory calculations confirmed characteristic type-IIa band alignments of all the five hybrids, facilitating to the photoinduced charge separation. Moreover, the closer contact caused by the strong anion-π interactions between electron donors and acceptors in hybrid 5 leads to the long-lived charge-separated states and improved electrical properties compared to the other hybrids.

3.
Inorg Chem ; 62(24): 9661-9670, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37267590

RESUMO

Low-dimensional inorganic-organic hybrid perovskites with high moisture tolerance and long-lived charge separation states have captured significant attention in the field of optoelectronic devices. To further achieve the relationship between crystal structures and stability, as well as charge separation behaviors, three one-dimensional hybrid perovskites containing electron-deficient naphthalene diimide ammonium (NDIEA) and electron-rich iodoplumbate chains, [(H2NDIEA)Pb2I6]·2DMF (1), [(H2NDIEA)2Pb5I14·(DMF)2]·4DMF (2), and [(HNDIEA)2Pb2I6]·3H2O (3), were synthesized. Crystal structure determinations revealed various synthesis conditions leading to different stacking modes, especially the inorganic lead iodide fraction, which resulted in different water resistances and charge-separated behaviors. The comprehensive analysis found that strong intermolecular interactions (anion-π interactions and π-π interactions), and matching energy levels between protonated NDIEA and iodoplumbate chains, can facilitate the generation of long-lived charge separation states and extraordinary moisture stability, even in the water environment. In addition, the conductivity behavior of 3 was also explored in detail.

4.
Bioorg Med Chem ; 88-89: 117336, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209638

RESUMO

As oncogene c-MYC is abnormally expressed during TNBC pathogenesis, stabilizing its promoter G-quadruplex (G4), which may thus inhibit c-MYC expression and promote DNA damage, may be a potential anti-TNBC strategy. However, large quantities of potential G4-forming sites exist in the human genome, which represents a potential drug selectivity problem. In order to achieve better recognition for c-MYC G4, we herein presented a new approach of designing small-molecule ligands by linking tandem aromatic rings with the c-MYC G4 selective binding motifs. Thus, a series of non-fused, conformation-tunable imidazole-biphenyl analogs were designed and synthesized. Among them, the optimal ligand appeared more effective on stabilizing c-MYC G4 than other types of G4s possibly through an adaptive, multi-site binding mode involved of end-stacking, groove-binding and loop-interacting. Then, the optimal ligand exerted good inhibitory activity on c-MYC expression and induced remarkable DNA damage, leading to the occurrence of G2/M phase arrest, apoptosis and autophagy. Furthermore, the optimal ligand exhibited potent antitumor effects in a TNBC xenograft tumor model. To sum up, this work offers new insights for the development of selective c-MYC G4 ligands against TNBC.


Assuntos
Antineoplásicos , Quadruplex G , Neoplasias de Mama Triplo Negativas , Humanos , Antineoplásicos/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ligantes , Proteínas Proto-Oncogênicas c-myc/genética , Imidazóis/farmacologia
5.
Small ; 18(26): e2201159, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35589558

RESUMO

Just as the heterojunctions in physics, donor-acceptor (D-A) heterostructures are an emerging class of photoactive materials fabricated from two semiconductive components at the molecular level. Among them, D-A hybrid heterostructures from organic and inorganic semiconductive components have attracted extensive attention in the past decades due to their combined advantages of high stability for the inorganic semiconductors and modifiability for the organic semiconductors, which are particularly beneficial to efficiently achieve photoinduced charge separation and transfer upon irradiations. In this review, by analogy with the heterojunctions in physics, a definition of the D-A heterostructures and their general design and synthetic strategies are given. Meanwhile, the D-A hybrid heterostructures are focused on and their recent advances in potential applications of photochromism, photomodulated luminescence, and photocatalysis summarized.

6.
Inorg Chem ; 61(21): 8153-8159, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35580155

RESUMO

Donor-acceptor (D-A) hybrid frameworks with visual X-ray photochromism at room temperature are fascinating because of their promising applications as X-ray detectors. Herein, a 3-fold interpenetrated D-A hybrid framework, [Eu(bcbp)1.5(DMF)(H2O)2][Co(CN)6]·4H2O·CH3OH (1), has been obtained by incorporating electron-rich Co(CN)63- into the electron-deficient europium viologen framework, which interestingly exhibits ultraviolet and low-power X-ray dual photochromism with a remarkable color change from brown to green. Experimental and theoretical studies revealed that the X-ray photochromic behavior of hybrid 1 could be attributed to its D-A hybrid structural feature increasing the extent of photoinduced electron transfer and thus photogenerated radical species upon X-ray irradiation. Meanwhile, due to the introduction of emissive lanthanide cations in the D-A system, hybrid 1 exhibits photomodulated luminescence properties.

7.
Inorg Chem ; 61(1): 105-112, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34918511

RESUMO

The self-assembly of electron-deficient protonated N, N'-dipyridyltetrachloroperylenediimide (4Cl-DPPDI) and electron-rich polyoxometalate acids HnXM12O40 (POMs; X = P or Si; M = W or Mo) resulted in four isomorphous donor-acceptor hybrid crystals 1-4 with segregated POM anions and one-dimensional racemic hydrogen-bonded 4Cl-DPPDI networks as electron-donor and -acceptor components, respectively. Because of the compact contacts between the POM anions and 4Cl-DPPDI tectons induced by anion-π interactions, besides enhanced photochromism, these four unique isostructural hybrids exhibited unusual room-temperature phosphorescence (RTP) emissions. More interestingly, owing to the facial compact contacts of two racemic 4Cl-DPPDI tectons induced by lone pair-π-assisted π-π interactions, they also showed unprecedented photon upconversion by triplet-triplet annihilation (TTA).

8.
Phys Chem Chem Phys ; 24(8): 5048-5051, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35144279

RESUMO

Inelastic electron transfer, regarded as one of the potential mechanisms to explain odorant recognition in atomic-scale processes, is still a matter of intense debate. Here, we study multiphonon processes of electron transfer using the Markvart model and calculate their lifetimes with the values of key parameters widely adopted in olfactory systems. We find that these multiphonon processes are as quick as the single phonon process, which suggests that contributions from different phonon modes of an odorant molecule should be included for electron transfer in olfaction. Meanwhile, the temperature dependence of electron transfer could be analyzed effectively based on the reorganization energy which is expanded into the linewidth of multiphonon processes. Our theoretical results not only enrich the knowledge of the mechanism of olfaction recognition, but also provide insights into quantum processes in biological systems.


Assuntos
Elétrons , Olfato , Transporte de Elétrons , Odorantes , Temperatura
9.
Plant Dis ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35486605

RESUMO

Industrial hemp (Cannabis sativa L.) is an ancient and economically important crop used in food, medicine, textile, and paper industries (Chandra et al. 2017). In July 2021, an estimated 30% of the industrial hemp plants showed wilted leaves and root rot in the greenhouse at the Modern Agriculture Demonstration Area Management Center, Harbin City, Heilongjiang Province, China. Initially, the diseased plants exhibited green and reversible wilting of lower canopy leaves. Upon progression the plants showed irreversible wilting. The epidermal tissue of root and rhizome showed slight cracks and the vascular bundle exhibited light brown discoloration, and then died. Six randomly selected disease plants were collected. Small fragments (5 mm) were cut from the infected roots, surface-sterilized with 70% ethanol for 30s and 1% sodium hypochlorite for 5 min and rinsed three times in sterile H2O. Then the small pieces were embedded on potato dextrose agar at 25℃ for 4 days and sub-cultured by hyphal tipping to isolate the fungus. A single-spore culture was obtained by monosporic isolation. The colonies were characterized by an abundant white cottony mycelium, which became gray or purple with age. The macroconidia were transparent, short to medium in length, straight to slightly curved, septate 0 to 4, 16.8 to 26.6 µm long × 3.5 to 4.1 µm wide. The apical cells were long and tapering to a point and the basal cells were notched. Microconidia were elliptic or kidney-shaped, and septate 0 to 4. The conidia were 4.2 to 11.3 µm long × 3.5 to 5.5 µm wide (n = 50). The morphological characteristics were very similar to those of Fusarium oxysporum (Leslie and Summerell 2006). For molecular identification, the internal transcribed spacer (ITS), translation elongation factor 1-α (TEF1) and RNA polymerase II beta subunit (RPB2) genes were amplified and sequenced with the primers ITS1/ITS4, EF-1/EF-2 (Uwaremwe et al. 2020), and 5f2/7c (O'Donnell et al. 2010). The 520 bp (ITS), 948 bp (TEF1), and 861 bp (RPB2) sequences were deposited in GenBank with acce. nos. MZ722998, OK180473 and OK180474, respectively. NCBI BLAST analysis showed 98 to 100% similarity with the sequences of F. oxysporum. Moreover, the sequences alignment similarity for the six isolates were 100%. Based on the morphological and molecular characteristics, the isolates were identified as F. oxysporum. For the pathogenicity test, 20 seedlings were inoculated 30 ml of a conidial suspension (106 conidia/ml) using the root dip method. Another set of 20 seedlings were inoculated with the same quantity of sterile distilled water as the controls. After inoculation, all seedlings were maintained in a greenhouse at 25°C ± 2, with a relative humidity of 60 to 70% and a 16 h light/8 h dark cycle. This test was repeated twice. The leaves of the inoculated seedlings gradually became yellow and exhibited wilting within 15 to 20 days, the epidermal tissue of root showed light brown discoloration. Eventually the plants were dead within 40 to 50 days after inoculation. The control seedlings did not show any wilt symptoms. F. oxysporum was re-isolated from the infected root tissues to fulfill the Koch's postulates. In addition to F. oxysporum, F. brachygibbosum, Pythium aphanidermatum, F. solani, and F. equiseti have also been reported to cause wilt symptoms of industrial hemp (Zamir et al. 2018). To our knowledge, this is the first report of Fusarium wilt on C. sativa caused by F. oxysporum in the Northeast China.

10.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499455

RESUMO

Mucin 1 (MUC1) has received increasing attention due to its high expression in breast cancer, in which MUC1 acts as a cancer antigen. Our group has been committed to the development of small-molecule TLR7 (Toll-like receptor 7) agonists, which have been widely investigated in the field of tumor immunotherapy. In the present study, we constructed a novel tumor vaccine (SZU251 + MUC1 + Al) containing MUC1 and two types of adjuvants: a TLR7 agonist (SZU251) and an aluminum adjuvant (Al). Immunostimulatory responses were first verified in vitro, where the vaccine promoted the release of cytokines and the expression of costimulatory molecules in mouse BMDCs (bone marrow dendritic cells) and spleen lymphocytes. Then, we demonstrated that SZU251 + MUC1 + Al was effective and safe against a tumor expressing the MUC1 antigen in both prophylactic and therapeutic schedules in vivo. The immune responses in vivo were attributed to the increase in specific humoral and cellular immunity, including antibody titers, CD4+, CD8+ and activated CD8+ T cells. Therefore, our vaccine candidate may have beneficial effects in the prevention and treatment of breast cancer patients.


Assuntos
Vacinas Anticâncer , Neoplasias , Camundongos , Animais , Receptor 7 Toll-Like/agonistas , Alumínio , Linfócitos T CD8-Positivos , Adjuvantes Imunológicos/farmacologia , Mucina-1/genética , Adjuvantes Farmacêuticos , Neoplasias/tratamento farmacológico
11.
Inorg Chem ; 60(21): 16233-16240, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648276

RESUMO

Donor-acceptor (D-A) hybrid crystals are an emerging kind of crystalline hybrid material composed of semiconductive inorganic donors and organic acceptors. Except for the intrinsic photochromism, recently we have reported that the anion-π polyoxometalate (POM)/naphthalenediimide (NDI) hybrid crystals could produce an interesting room temperature phosphorescence (RTP) quantum yield up to 7.2%. Herein, we extended into core-substituted NDIs and anticipated the regulation of their photochromic and RTP properties. Thus, two hybrid crystals, namely (H4BDMPy-Br2NDI)·(NMP)4·(HPW12O40) (1) and (H4BDMPy-I2NDI)·(HPW12O40) (2) (H2BDMPy-Br2NDI: N,N'-bis(3,5-dimethylpyrazolyl)-2,6-dibromo-1,4,5,8-naphthalenediimide and H2BDMPy-I2NDI: N,N'-bis(3,5-dimethylpyrazolyl)-2,6-diiodide-1,4,5,8-naphthalenediimide), have been synthesized from phosphotungstic anions (PW12O403-) and Br or I core-substituted NDIs. Compared to the core-unsubstituted analogues (H4BDMPy-NDI)·(NMP)4·(HPW12O40) (3), 2 with photosensitive iodine substituents is more sensitive to light, which can become discolored under natural light. As a result of the heavy-atom effect, hybrid 1 exhibits remarkable RTP with the quantum yield up to 10.2% and a lifetime of 1.14 ms.

12.
Arch Gynecol Obstet ; 303(4): 925-931, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33033866

RESUMO

PURPOSE: To summarize the clinical characteristics and treatments of preeclampsia complicated with hyponatremia. METHODS: We reported a new case of preeclampsia complicated with severe hyponatremia; searched for relevant articles from the PubMed, Scopus and Cochrane databases; and reviewed all reported cases. RESULTS: Twenty-one reported cases were found. Our case is 22nd, and the serum sodium level in this case was the lowest reported. After treatment comprising fluid restriction, hypertonic saline and caesarean section, a relatively good outcome was achieved. In all reported cases, SIADH, preeclampsia or the combined effect of preeclampsia and induced nephrotic syndrome were the speculated pathogeny. Termination was performed due to adverse manifestations; six cases underwent transvaginal deliveries, and sixteen cases underwent caesarean section. Fifteen patients recovered from hyponatremia within 72 h after delivery. CONCLUSION: The pathogenesis of hyponatremia occurring in patients with preeclampsia is still unclear. Termination of the pregnancy led to a stabilization of the sodium level, ICU monitoring was necessary, and fluid restriction and hypertonic saline intake were applied; however, there was no evidence of the effectiveness of the treatments.


Assuntos
Hiponatremia/complicações , Pré-Eclâmpsia/sangue , Adulto , Feminino , Humanos , Hiponatremia/terapia , Gravidez
13.
Plant Dis ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33904327

RESUMO

Industrial hemp is an economically important plant with traditional uses for textiles, paper, building materials, food and medicine (Li 1974; Russo et al. 2008; Zlas et al. 1993). In August 2020, an estimated 80% of the industrial hemp plants with leaf spots were observed in greenhouse in Minzhu town, Harbin City, Heilongjiang Province, China (45.8554°N, 126.8167°E), resulting in yield losses of 20%. Leaf symptoms began as small spots on the upper surface of leaves and gradually developed into brown spots with light yellow halos. These irregular spots expanded gradually and eventually covered the entire leaf; the center of the spots was easily perforated. To identify the pathogen, 20 diseased leaves were collected, and small sections of (3 to 5 mm) were taken from the margins of lesions of infected leaves. The pieces were sterilized with 75% alcohol for 30 s, a 0.1% mercuric chloride solution for 1 min, and then rinsed three times with sterile water. Samples were then cultured on potato dextrose agar at 28℃ in darkness for 4 days. A single-spore culture was obtained by monosporic isolation. Conidiophores were simple or branched, straight or flexuous, brown, and measured 22 to 61 µm long × 4 to 5 µm wide (n = 50). Conidia were solitary or in chains, brown or dark brown, obclavate, obpyriform or ellipsoid. Conidia ranged from 23 to 55 µm long × 10 to 15 µm wide (n = 50) with one to eight transverse and several longitudinal septa. For molecular identification (Jayawardena et al. 2019), genomic DNA of pathogenic isolate (MZ1287) was extracted by a cetyltrimethylammonium bromide protocol. Four gene regions including the rDNA internal transcribed spacer (ITS), glyceraldehyde-3-phosplate dehydrogenase (GAPDH), translation elongation factor 1-alpha (TEF1) and RNA polymerase II beta subunit (RPB2) were amplified with primers ITS1/ITS4, GDF1/GDR1, EF1-728F/EF1-986R and RPB2-5F/RPB2-7cR, respectively (White et al. 1990). Resulting sequences were deposited in GenBank with accession numbers of MW272539.1, MW303956.1, MW415414.1 and MW415413.1, respectively. A BLASTn analysis showed 100% homology with A. alternata (GenBank accession nos. MN615420.1, MH926018.1, MN615423.1 and KP124770.1), respectively. A neighbor-joining phylogenetic tree was constructed by combining all sequenced loci in MEGA7. The isolate MZ1287 clustered in the A. alternata clade with 100% bootstrap support. Thus, based on morphological (Simmons 2007) and molecular characteristics, the pathogen was identified as A. alternata. To test pathogenicity, leaves of ten healthy, 2-month-old potted industrial hemp plants were sprayed using a conidial suspension (1×106 spores/ml). Control plants were sprayed with sterile water. All plants were incubated in a greenhouse at 25℃ for a 16 h light and 8 h dark period at 90% relative humidity. The experiment was repeated three times. After two weeks, leaf spots of industrial hemp developed on the inoculated leaves while the control plants remained asymptomatic. The A. alternata pathogen was re-isolated from the diseased leaves on inoculated plants, fulfilling Koch's postulates. Based on morphology, sequencing, and pathogenicity test, the pathogen was identified as A. alternata. To our knowledge, this is the first report of A. alternata causing leaf spot disease of industrial hemp (Cannabis sativa L.) in China and is worthy of our attention for the harm it may cause to industrial hemp production.

14.
Mol Biol Rep ; 47(6): 4303-4309, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32418113

RESUMO

Wheat stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is a fungus that causes the devastating fungalwheat stem rust disease in wheat production. Rapid identification of the physiological races of Pgt are very importance for the prevention of wheat stem rust. In this paper we developed a molecular method to identify the most prevalent race of Pgt, as a supplement for traditionally used host-specific methods. Amplified fragment length polymorphism (AFLP) was employed as a means of analyzing DNA polymorphisms in six common physiological races of Pgt in China and Ug99. In total, 64 pairs of primers were used for AFLP screening of race-specific molecular markers. One primer pair-namely, E7/M7 (5'-GACTGCGTACCAATTCG G-3'/5'-GATGAGTCCTGAGTAACGG-3')-yielded a unique band for the race 34MKG that was purified and cloned into the pGEM-T vector for sequencing. We then designed a new primer pairs (sequence-characterized amplified region marker) to amplify the 171-bp fragment and confirmed that the marker was highly specific for 34MKG. These results provide a new tool for monitoring different races of Pgt for improved control of wheat stem rust in China.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Puccinia/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Basidiomycota/genética , China , Mapeamento Cromossômico/métodos , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo Genético/genética , Puccinia/metabolismo , Triticum/genética , Triticum/microbiologia
15.
Rev Cardiovasc Med ; 20(2): 81-89, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31345000

RESUMO

Periodontitis is one of the risk factors associated with peripheral artery disease. This meta-analysis evaluates how periodontitis contributes to the pathogenesis and progression of peripheral artery disease. We systematically searched electronic databases Ovid Medline, Embase, Cochrane Library and Pubmed. Grey literature was also searched via Google Scholar. All studies evaluating the relationship between the incidence of periodontitis and peripheral artery disease were included. Subgroup analyses of carotid artery disease and lower extremity arterial disease were also conducted. Odds ratios (OR) and 95% confidence intervals (CI) were pooled and analyzed. The I² statistic was used to evaluate heterogeneity. Within a total of 25 studies, including 22,090 participants based on eligibility criteria, the incidence of peripheral artery disease was significantly higher among those with periodontitis (OR: 1.60, 95% CI 1.41-1.82, P < 0.001, I² = 80.5%). In subgroup analysis, periodontitis was still a risk for lower extremity arterial disease (OR: 3.00, 95% CI 2.23-4.04, P < 0.001, I² = 0%) and carotid artery disease (OR: 1.39, 95% CI 1.24-1.56, P < 0.001, I² = 79.4%). Periodontitis is significantly associated with the incidence of lower extremity arterial disease and carotid artery disease.


Assuntos
Doenças das Artérias Carótidas/epidemiologia , Extremidade Inferior/irrigação sanguínea , Periodontite/epidemiologia , Doença Arterial Periférica/epidemiologia , Doenças das Artérias Carótidas/diagnóstico , Humanos , Incidência , Periodontite/diagnóstico , Doença Arterial Periférica/diagnóstico , Prognóstico , Medição de Risco , Fatores de Risco
16.
Antonie Van Leeuwenhoek ; 112(5): 695-702, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30467662

RESUMO

A novel Gram-stain positive, aerobic, non-motile bacterial strain, designated Z1T, was isolated from a sample of petroleum-contaminated soil collected in Daqing, Heilongjiang province, China and characterised with a series of taxonomic approaches. The morphological and chemotaxonomic properties of the isolate were typical of those of members of the genus Rhodococcus. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Z1T belongs to the genus Rhodococcus and clustered with Rhodococcus maanshanensis DSM 44675T (99.2%, sequence similarity) and Rhodococcus tukisamuensis JCM 11308T (97.9%), respectively. However, the DNA-DNA hybridizations between strain Z1T and R. maanshanensis DSM 44675T and R. tukisamuensis JCM 11308T were both less than 70%. The optimal growth temperature and pH for strain Z1T were found to be at 28 °C and at pH 7.0. The peptidoglycan was found to contain meso-diaminopimelic acid; arabinose, galactose and glucose were detected as diagnostic sugars. The main polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified lipid; MK-8(H2) was found as the major menaquinone. The major fatty acids were identified as C16:0, 10-methyl C18:0 and C18:1ω9c. Mycolic acids were found to be present. The G + C content of the genomic DNA was determined to be 66.7 mol%. Based on a comparative analysis of phenotypic and genotypic characteristics, in combination with DNA-DNA hybridization results, strain Z1T can be distinguished from the type strains of its two close neighbours as a novel species of the genus Rhodococcus, for which the name Rhodococcus daqingensis sp. nov. is proposed. The type strain is Z1T (= CGMCC 1.13630T = DSM 107227T).


Assuntos
Petróleo/análise , Rhodococcus/isolamento & purificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Petróleo/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Rhodococcus/classificação , Rhodococcus/genética , Rhodococcus/metabolismo , Solo/química
17.
Antonie Van Leeuwenhoek ; 110(9): 1113-1120, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28488064

RESUMO

A novel Gram-positive, aerobic, non-motile strain, designated strain M1T, was isolated from sunflower root (Helianthus annuus L.) and characterised using a polyphasic taxonomic approach. The morphological and chemotaxonomic properties of the isolate were typical of those of members of the genus Rhodococcus. Phylogenetic analyses based on 16S rRNA gene sequence showed that strain M1T belongs to the genus Rhodococcus and clustered with Rhodococcus canchipurensis MBRL 353T (99.1%, sequence similarity) and Rhodococcus pedocola UC12T (98.7%). However, the DNA-DNA hybridizations between strain M1T and R. canchipurensis MBRL 353T and R. pedocola UC12T were found to be 52.8 ± 0.7 and 41.8 ± 0.2%, respectively. The optimal growth temperature and pH for strain M1T was found to be at 28 °C and at pH 7.0. The peptidoglycan was found to contain meso-diaminopimelic acid; galactose, glucose and arabinose were detected as diagnostic sugars. The main polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside; MK-8(H2) was found to be the dominant menaquinone. The major fatty acids were identified as C16:0, 10-methyl C18:0 and C18:1 ω9c. Mycolic acids were found to be present. The G+C content of the genomic DNA was determined to be 69.5 mol%. Based on a comparative analysis of phenotypic and genotypic characteristics, in combination with DNA-DNA hybridization results, the isolate is concluded to represent a novel species of the genus Rhodococcus, for which the name Rhodococcus gannanensis sp. nov. is proposed. The type strain is M1T (=CGMCC 1.15992T = DSM 104003T).


Assuntos
Helianthus/microbiologia , Filogenia , Rhodococcus/classificação , Rhodococcus/genética , Composição de Bases , Parede Celular/química , Endófitos/química , Endófitos/classificação , Endófitos/genética , Hibridização de Ácido Nucleico , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Rhodococcus/química , Especificidade da Espécie
18.
BMC Plant Biol ; 16(1): 124, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27234464

RESUMO

BACKGROUND: MicroRNAs (miRNAs) play a critical role in responses to biotic and abiotic stress and have been characterized in a large number of plant species. Although flax (Linum usitatissimum L.) is one of the most important fiber and oil crops worldwide, no reports have been published describing flax miRNAs (Lus-miRNAs) induced in response to saline, alkaline, and saline-alkaline stresses. RESULTS: In this work, combined small RNA and degradome deep sequencing was used to analyze flax libraries constructed after alkaline-salt stress (AS2), neutral salt stress (NSS), alkaline stress (AS), and the non-stressed control (CK). From the CK, AS, AS2, and NSS libraries, a total of 118, 119, 122, and 120 known Lus-miRNAs and 233, 213, 211, and 212 novel Lus-miRNAs were isolated, respectively. After assessment of differential expression profiles, 17 known Lus-miRNAs and 36 novel Lus-miRNAs were selected and used to predict putative target genes. Gene ontology term enrichment analysis revealed target genes that were involved in responses to stimuli, including signaling and catalytic activity. Eight Lus-miRNAs were selected for analysis using qRT-PCR to confirm the accuracy and reliability of the miRNA-seq results. The qRT-PCR results showed that changes in stress-induced expression profiles of these miRNAs mirrored expression trends observed using miRNA-seq. Degradome sequencing and transcriptome profiling showed that expression of 29 miRNA-target pairs displayed inverse expression patterns under saline, alkaline, and saline-alkaline stresses. From the target prediction analysis, the miR398a-targeted gene codes for a copper/zinc superoxide dismutase, and the miR530 has been shown to explicitly target WRKY family transcription factors, which suggesting that these two micRNAs and their targets may significant involve in the saline, alkaline, and saline-alkaline stress response in flax. CONCLUSIONS: Identification and characterization of flax miRNAs, their target genes, functional annotations, and gene expression patterns are reported in this work. These findings will enhance our understanding of flax miRNA regulatory mechanisms under saline, alkaline, and saline-alkaline stresses and provide a foundation for future elucidation of the specific functions of these miRNAs.


Assuntos
Álcalis/metabolismo , Linho/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , RNA de Plantas/genética , Cloreto de Sódio/metabolismo , Linho/metabolismo , Perfilação da Expressão Gênica , MicroRNAs/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA de Plantas/metabolismo , Estresse Fisiológico
19.
Inorg Chem ; 54(17): 8375-9, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26347291

RESUMO

Poor stability has long been a major obstacle to the practical applications of metal-organic framework (MOF) photocatalysts. This problem can be overcome by the use of structural interpenetration. In this work, by modifying Ru metalloligands, we have rationally designed two Ru-polypyridine based MOFs (with non-interpenetrated and interpenetrated structures, respectively), both of which exhibit similar photocatalytic activities for CO2 photoreduction. Remarkably, the interpenetrated Ru-MOF possesses good photocatalytic durability and recyclability, and shows much higher thermal and photic stability in comparison with its non-interpenetrated counterpart. To the best of our knowledge, this is the first time that the stability of MOF photocatalysts was improved by using structural interpenetration.

20.
Inorg Chem ; 54(18): 8872-4, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26355748

RESUMO

A new entangled metal-organic framework shows reversible structural dynamics and luminescence changing in response to the loss of guest H2O molecules. Furthermore, an intense and sensitive luminescence turn-on sensing was observed by the naked eye for 1 upon detection of the volatile organic solvent molecule CH3CN, accompanied by reversible structural transformation.


Assuntos
Colorimetria , Irídio/química , Compostos Organometálicos/efeitos da radiação , Acetonitrilas/análise , Luminescência , Compostos Organometálicos/química
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