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1.
J Nanosci Nanotechnol ; 20(2): 1046-1055, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383104

RESUMO

Silver nanoparticles can be used to effectively disinfect Enterococcus faecalis (E. faecalis) in dental root canal therapy, of which the mechanism remains unclear. In the current study, we explored the effect of silver nanoparticles on bacterial growth and changes in the transcriptome of E. faecalis using RNA-sequencing technology. Results showed that silver nanoparticles significantly inhibited growth of E. faecalis by prolonging the lag phase in a dose dependent manner. A total of 100 differentially expressed genes (DEGs) including 3 upregulated and 97 downregulated DEGs were obtained in E. faecalis after treatment with silver nanoparticles. We performed Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses on these DEGs. Functional annotation of DEGs showed that transport and metabolism, such as carbohydrate metabolic process, peptide transport, and amide transport were most significantly enriched. Dysregulated genes were significantly enriched in pathways related to carbohydrate and energy metabolism, and the TCA cycle may be a major mechanism for E. faecalis with silver nanoparticle treatment. These data indicated changes in the transcriptome of E. faecalis after silver nanoparticle treatment, thus providing a mechanism for supporting application of silver nanoparticles for disinfection of E. faecalis during and after root canal therapy.

2.
Bioresour Technol ; 295: 122287, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31669873

RESUMO

Johannesburg-Sulfur autotrophic denitrification (JHB-SAD) system was investigated for the combined treatment of leachate and municipal wastewater with low strength and low COD/TN ratio. The average removal efficiencies for chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were 85.2%, 96.2% and 75.8%, respectively. The municipal wastewater and leachate (dosing of 2.1‰, v/v) can be treated via the JHB-SAD system to achieve efficient nutrients removal. The mass balance calculations suggested that 58.1-69.8% TN was removed in JHB unit and 32.9-41.2% TN in SAD unit. Further, the denitrifying phosphorus removal process occurred in the anoxic zone. EEM-PARAFAC analysis found that the protein-like materials were more efficiently removed than fulvic-like materials in JHB-SAD system. The tryptophan-like materials had the most positive linear relationship with the COD concentrations. The bacterial community was difference between JHB and SAD unit. Furthermore, bacteria abundance relating to nitrogen removal increased with additional leachate.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31692181

RESUMO

We report the template-free synthesis and characterization of a new type of porphyrin/quinoidal bithiophene based conjugated macrocycles. X-ray crystallographic analysis on the dimer ( 2MC ) reveals a cyclophane-like geometry with large dihedral angles between the porphyrin and the neighboring thiophene rings. Accordingly, NMR measurements and theoretical calculations confirm a localized aromatic character of the porphyrin/thiophene rings and quinoidal character of the bithiophene linkers. Restricted rotation of the thiophene rings linked to the porphyrin unit was observed by variable-temperature NMR measurements . The dication ( 2MC 2+ ) adopts a chair-shaped conformation to facilitate π-electron delocalization along the whole macrocycle. As a result, the molecule is globally aromatic, with a dominant 54π conjugation pathway. The trimer ( 3MC ) also shows localized aromatic character of porphyrin rings and conformational flexibility, but its dication ( 3MC 2+ ) is rigid and globally aromatic, with a dominant 82π conjugation pathway.

4.
Thorac Cancer ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694073

RESUMO

BACKGROUND: The main cause of cancer death is lung cancer (LC) which usually presents at an advanced stage, but its early detection would increase the benefits of treatment. Blood is particularly favored in clinical research given the possibility of using it for relatively noninvasive analyses. Copy number variation (CNV) is a common genetic change in tumor genomes, and many studies have indicated that CNV-derived cell-free DNA (cfDNA) from plasma could be feasible as a biomarker for cancer diagnosis. METHODS: In this study, we determined the possibility of using chromosomal arm-level CNV from cfDNA as a biomarker for lung cancer diagnosis in a small cohort of 40 patients and 41 healthy controls. Arm-level CNV distributions were analyzed based on z score, and the machine-learning algorithm Extreme Gradient Boosting (XGBoost) was applied for cancer prediction. RESULTS: The results showed that amplifications tended to emerge on chromosomes 3q, 8q, 12p, and 7q. Deletions were frequently detected on chromosomes 22q, 3p, 5q, 16q, 10q, and 15q. Upon applying a trained XGBoost classifier, specificity and sensitivity of 100% were finally achieved in the test group (12 patients and 13 healthy controls). In addition, five-fold cross-validation proved the stability of the model. Finally, our results suggested that the integration of four arm-level CNVs and the concentration of cfDNA into the trained XGBoost classifier provides a potential method for detecting lung cancer. CONCLUSION: Our results suggested that the integration of four arm-level CNVs and the concentration from of cfDNA integrated withinto the trained XGBoost classifier could become provides a potentially method for detecting lung cancer detection.

5.
Arterioscler Thromb Vasc Biol ; : ATVBAHA119313440, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31694393

RESUMO

OBJECTIVE: Thoracic aortic dissection (TAD) is a fatal disease that leads to aortic rupture and sudden death. However, little is known about the effect and molecular mechanism of S-nitrosylation (SNO) modifications in TAD formation. Approach and Results: SNO levels were higher in aortic tissues from TAD patients than in those from healthy controls, and PLS3 (plastin-3) SNO was identified by liquid chromatography-tandem mass spectrometry analysis. Furthermore, tail vein administration of endothelial-specific adeno-associated viruses of mutant PLS3-C566A (denitrosylated form) suppressed the development of TAD in mice, but the wild-type PLS3 (S-nitrosylated form) virus did not. Mechanistically, Ang II (angiotensin II)-induced PLS3 SNO enhanced the association of PLS3 with both plectin and cofilin via an iNOS (inducible nitric oxide synthase)-dependent pathway in endothelial cells. The formation of PLS3/plectin/cofilin complex promoted cell migration and tube formation but weakened adherens junction formation in Ang II-treated endothelial cells. Interestingly, denitrosylated form of PLS3 partially mitigated Ang II-induced PLS3/plectin/cofilin complex formation and cell junction disruption. Additionally, the inhibition of iNOS attenuated PLS3 SNO and the association of PLS3 with plectin and cofilin, thereby modulating endothelial barrier function. CONCLUSIONS: Our data indicate that protein SNO modification in endothelial cells modulates the progression of aortic aneurysm and dissection. The iNOS-mediated SNO of PLS3 at the Cys566 site promoted its interaction with cofilin and plectin, thus contributing to endothelial barrier disruption and pathological angiogenesis in TAD.

6.
Bioresour Technol ; 296: 122340, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31704601

RESUMO

A biological aerated filter (BAF) with sulfur and pyrite as fillers were structured to simultaneously remove NH4+-N, NO3--N and PO43--P from secondary effluent. When dissolved oxygen (DO) was 1.2-1.5 mg/L, effluent concentration of NH4+-N, NO3--N and PO43--P were below 0.65, 0.47 and 0.18 mg/L, respectively. Meanwhile, Fe2+ production via decomposing pyrite could improve autotrophic denitrification performance. Besides, sulfur and pyrite autotrophic denitrification process (PAD and SAD) aligned with the Zero-order and First-order kinetics models, respectively, indicating that the sulfur had excellent capability of providing electron. Moreover, there was a positive correlation between the nitrogen removal performance and protein-like substances in extracellular polymeric substances. Bacterial community analysis suggested the nitrifiers and autotrophic denitrifiers were simultaneously enriched. Principal component analysis indicated that the DO concentration and type of electron donors impacted bacterial community. Consequently, BAF combined with PAD and SAD processes provides an alternative method to remove nutrients.

7.
Biomed Pharmacother ; 121: 109580, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31704614

RESUMO

Colorectal cancer (CRC) is a malignant tumor with a high incidence and death rate in the world. Molecular interactions inside cells or tissues during tumor occurrence, development, and drug resistance are important for disease prevention and treatment. The long non-coding RNA SNHG14 has been proven to exert its oncogenic function in multiple cancers. However, there is no study regarding the role of SNHG14 in CRC research. In the present study, we applied RT-qPCR and western blot to determine the gene expression levels. MTT and TUNEL assays were used to detect cell proliferation and apoptosis rate. Cell migration and invasion abilities were determined by wound healing and transwell assays, respectively. StarBase was used to predict the potential binding sites and luciferase reporter assay was applied to confirm the direct interactions. Besides, we conducted a xenograft experiment to detect tumor growth rate in vivo. Our results showed that SNHG14 and ATG14 were both significantly higher in CRC tumor tissues than the normal ones, while miR-186 was decreased. The similar results were also observed in CRC cell lines. We confirmed that SNHG14 could directly interact with miR-186 and inhibited its expression. Meanwhile, miR-186 could directly bind ATG14 to inhibit its expression level. In vitro experiments showed that higher expression of SNHG14 led to higher cell proliferation, migration and invasion, while miR-186 significantly inhibited these tumor phenotypes. Furthermore, overexpression of ATG14 could strongly recover the CRC phenotypes attenuated by shSNHG14 or miR-186 mimics. Interestingly, we constructed cisplatin-resistant CRC cells and found that overexpression of ATG14 significantly enhanced the cell proliferation rate and inhibited cell apoptosis. Our research indicated that the novel axis of SNHG14/miR-186/ATG14 could play a vital role in regulating CRC cell progression. Moreover, this axis showed its clinical potential in regulating cisplatin resistance during CRC treatment.

8.
Br J Nutr ; : 1-26, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31699162

RESUMO

Both konjac glucomannan (KGM) and inulin oligosaccharide have been shown to improve bowel function, but their effects on the mucosal barrier function and immunity are not fully understood. The aim of this study was to determine effects of a low-level supplementation of dietary fibres on the colonic mucosal barrier function, antioxidant enzyme defense and immunity. C57BL/6J mice (six weeks of age, 8 per group) were randomly assigned to consume one of the following diets: control, or control diet supplemented with 2% (w/w) of KGM, inulin oligosaccharide (degree polymerization=8) or KGM+Inulin (1% w/w each). Fresh feces were collected on d 19-21 for analyses of short-chain fatty acid and microflora. Mice were sacrificed on d 22 after fasting. Segments of colon tissues were processed for histological procedure and stained for acidic mucins and tight junction protein marker ZO-1. The remaining tissues were processed to determine gene expressions of mucin 2, tight junction proteins, antioxidant enzymes and cytokines. The plasma TNF-α and IL-10 level were also measured to investigate the systemic effects of dietary fibres. Results indicated that KGM, inulin and K+I significantly increased the mucosal layer thickness, mucin density (granule number/crypt) and gene expression of Muc2 as compared with the control. All fibre treatments increased the gene expressions of ZO-1, occludin, GPX, GST, catalase, and IL-10. In addition, all fibre treatments increased fecal butyrate and probiotics, and plasma IL-10 concentrations. In conclusion, supplementation of low-level, 2% (w/w), of KGM and inulin was sufficient to enhance the mucosal barrier function and anti-inflammatory status.

9.
Cell Death Dis ; 10(11): 853, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700002

RESUMO

Hepatopulmonary syndrome (HPS) is a serious vascular complication in the setting of liver disease. Factors produced by the liver are essential to regulate pulmonary angiogenesis in the pathogenesis of HPS; however, the pathogenic mechanisms of pulmonary angiogenesis are not fully understood. We investigated the role of HPS rat serum exosomes (HEs) and sham-operated rat serum exosomes (SEs) in the regulation of angiogenesis. We found that HEs significantly enhance PMVEC proliferation, migration, and tube formation. We further identified miR-194 was the most notably increased miRNA in HEs compared to SEs. Once released, hepatocyte-derived exosomal miR-194 was internalized by PMVECs, leading to the promotion of PMVEC proliferation, migration, and tube formation through direct targeting of THBS1, STAT1, and LIF. Importantly, the pathogenic role of exosomal miR-194 in initiating angiogenesis was reversed by P53 inhibition, exosome secretion inhibition or miR-194 inhibition. Additionally, high levels of miR-194 were found in serum exosomes and were positively correlated with P(A-a)O2 in HPS patients and rats. Thus, our results highlight that the exosome/miR-194 axis plays a critical pathologic role in pulmonary angiogenesis, representing a new therapeutic target for HPS.

10.
Neurobiol Aging ; 2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31564376

RESUMO

Mutations in the podocalyxin-like gene (PODXL) have been recently identified in a consanguineous Indian family with juvenile-onset Parkinson's disease (PD) and 3 unrelated patients with PD. However, the pathogenicity of PODXL mutations in the disease and their role in other PD populations remain unclear. The aim of this study was to investigate the PODXL mutations in a Taiwanese cohort with familial and young-onset PD. Among 531 participants, including 161 probands from PD pedigrees without known PD-causative gene mutations and 370 patients with early-onset PD (age of onset <50 years), all exons and exon-intron boundary junctions of PODXL were analyzed by Sanger sequencing. We did not find any pathogenic coding variants or previously reported mutations, indicating that PODXL mutations may not play a role in familial or early-onset PD in this Taiwanese population.

11.
J Mater Chem B ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657427

RESUMO

The present study investigates the properties and use as wound-dressing materials of hydrogels made of negatively charged 3-sulfopropyl methacrylate (SA) and positively charged [2-(methacryloyloxy)ethyl]trimethylammonium (TMA) to form poly(SA-co-TMA) gels with/without a charge bias. Their actual chemical compositions were ascertained by XPS which revealed a fair control of the final gel composition obtained from the initial molar ratio in the reaction solution. Zeta potential measurements confirmed the controlled charge bias on which swelling ratio was found to strongly depend, i.e., positively charged or negatively charged gels have a higher tendency to swell than poly(SA-co-TMA) made of 50 mol% of each unit. The anti-biofouling properties were also correlated to the charge bias, i.e., negatively charged and neutral gels resisted well to biofouling by fibrinogen and whole blood, and were much less cytotoxic than their positive counterparts. Applied as wound-dressing materials onto diabetic wounds, it was found that wound closure was almost reached after 21 days, regardless of the gel composition. However, histological analysis revealed that positively charged gels accelerated hemostasis, while neutral gels, much less cytotoxic, were more efficient in the following stages during which the granulation layer and dermis were fully remodelled leading to a dense fibroblast population and thick collagen with no sign of inflammation. All in all, this study sheds light on the effects of charge bias on different wound healing stages and proves the efficiency of pseudo-zwitterionic poly(SA-co-TMA) to heal diabetic wounds for the first time.

12.
J Exp Bot ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31641755

RESUMO

The molecular mechanisms underlying seed dormancy and germination are not fully understood. Here we show that Arabidopsis thaliana Seed dormancy 4-Like (AtSdr4L) is a novel specific regulator of seed dormancy and germination. AtSdr4L encodes a protein with unknown biochemical function that is localized in the nucleus and expressed specifically in seeds. Loss of function of AtSdr4L results in increased seed dormancy. The germination of freshly harvested atsdr4l seeds is insensitive to gibberellin (GA). After-ripened atsdr4l seeds are hypersensitive to paclobutrazol (PAC) but show unaltered abscisic acid (ABA) sensitivity. Several GA biosynthesis genes and GA-regulated cell wall remodeling genes are down-regulated in atsdr4l in both dormant and after-ripened seeds. These results suggest that the atsdr4l mutation causes both decreased GA biosynthesis and response. In addition, a genetic analysis revealed that AtSdr4L is epistatic to DELAY OF GERMINATION1 (DOG1) for dormancy and acts upstream of RGA-LIKE 2 (RGL2) in the GA pathway. We propose that AtSdr4L regulates seed dormancy and germination by mediating both DOG1 and GA pathways.

13.
J Am Chem Soc ; 141(41): 16266-16270, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31565929

RESUMO

We report a [6]cyclo-para-phenylmethine ([6]CPPM) macrocycle that shows benzene-like electronic properties. Its mesityl derivative, [6]CPPM-Mes, was isolated in crystalline form. X-ray analysis reveals a C2h symmetry, and the bond lengths of the benzenoid/quinoid rings are averaged via resonance. One averaged 1H NMR peak for the protons on the backbone was observed at room temperature, but it was split into one shielded and one deshielded resonance below 198 K, consistent with its globally aromatic character with a dominant 30π conjugation pathway along the periphery. It exhibits open-shell diradical character with a moderate singlet-triplet energy gap (ΔES-T = -6.23 kcal/mol). Its dication is antiaromatic and open-shell, showing a smaller ΔES-T value (-4.18 kcal/mol). Overall, [6]CPPM behaves like an open-shell aromatic "super-benzene".

14.
Mol Biol Rep ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31612410

RESUMO

Circular RNA (circRNA), a novel type of non-coding RNA that consists of a circular loop, has been demonstrated to act as a "sponge" for microRNAs (miRNAs). However, the role of circRNAs in keloid remains unknown. In this study, we investigated circRNA expression profiles in keloid to identify potential diagnostic and therapeutic circRNAs. We performed a circRNA microarray assay to determine circRNA expression in keloid and paired normal skin tissues. Quantitative reverse transcription polymerase chain reaction was used to evaluate the expression levels of candidate circRNAs. The most significantly over-expressed circRNA was used to predict putative miRNA targets and the binding sites of miRNAs with this circRNA. Finally, we constructed a circRNA-miRNA interaction network and carried out gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. We found 52 significantly upregulated and 24 downregulated circRNAs in keloid compared with normal skin tissue. We confirmed that hsa_circ_0057452, hsa_circ_0007482, hsa_circ_0020792, hsa_circ_0057342, and hsa_circ_0043688 were significantly upregulated in keloid tissues. Analysis of the circRNA-miRNA interaction network revealed that circRNAs could interact with miRNAs, including miRNA-29a, miRNA-23a-5p and miRNA-1976. GO and KEGG analyses indicated that these target genes were involved in biological functions and signaling pathways that may play vital roles in the pathogenesis of keloid. This study revealed that circRNAs are potentially implicated in the development of keloid and could serve as novel diagnostic and therapeutic targets.

15.
Inorg Chem ; 58(20): 14193-14203, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31584269

RESUMO

Topotactic reduction of the perovskite oxide TbBaCo2O5.5 with CaH2 leads to a new crystalline phase TbBaCo2O4.5, adopting a 2 × 2 × 1 superstructure compared to TbBaCo2O5.5. The structure consists of a corner-shared network of square pyramidal CoO5 and trigonal planar CoO3 units. Magnetic susceptibility and variable temperature neutron diffraction data reveal that TbBaCo2O4.5 adopts a G-type antiferromagnetically ordered structure (TN ∼ 322 K). The ordered moments are consistent with the presence of low-spin Co2+ (S = 1/2) in trigonal-planar coordination and high-spin Co2+ centers in square pyramidal coordination. TbBaCo2O4.5 shows lower conductivity than TbBaCo2O5.5, which is consistent with the p-type conduction behavior. The unique anion vacancy arrangements in TbBaCo2O4.5 further complement the role of A-cations in controlling the oxygen vacancy distribution in LnBaCo2O5+δ series and demonstrate more opportunity to tune the structural and physical properties based on cationic and anionic lattice coupling.

16.
Chin Med J (Engl) ; 132(18): 2143-2149, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31478926

RESUMO

BACKGROUND: Thyroid autoimmunity (TAI) is prevalent among women of reproductive age and associated with adverse pregnancy outcomes. This study aimed to investigate the association between iron nutritional status and the prevalence of TAI in women during the first trimester of pregnancy and in non-pregnant women of childbearing age. METHODS: Cross-sectional analysis of 7463 pregnant women during the first trimester of pregnancy and 2185 non-pregnant women of childbearing age nested within the sub-clinical hypothyroid in early pregnancy study, a prospective collection of pregnant and non-pregnant women's data, was conducted in Liaoning province of China between 2012 and 2015. Serum thyrotropin, free thyroxine, thyroid peroxidase antibodies (TPOAbs), thyroglobulin antibodies (TgAbs), serum ferritin, and urinary iodine were measured. Iron deficiency (ID) was defined as serum ferritin <15 µg/L and iron overload (IO) was defined as ferritin >150 µg/L. TPOAb-positive was defined as >34 U/mL and TgAb-positive was defined as >115 U/mL. Multilevel logistic regression was conducted to examine the association between TAI and different iron nutritional status after adjusting for potential confounders. RESULTS: The prevalence of isolated TPOAb-positive was markedly higher in women with ID than those without ID, in both pregnant and non-pregnant women (6.28% vs. 3.23%, χ = 10.264, P = 0.002; 6.25% vs. 3.70%, χ = 3,791, P = 0.044; respectively). After adjusting for confounders and the cluster effect of hospitals, ID remained associated with TPOAb-positive in pregnant and non-pregnant women (odds ratio [OR]: 2.111, 95% confidence interval [CI]: 1.241-3.591, P = 0.006; and OR: 1.822, 95% CI: 1.011-3.282, P = 0.046, respectively). CONCLUSION: ID was associated with a higher prevalence of isolated TPOAbs-positive, but not with isolated TgAb-positive, in both pregnant women during the first trimester of pregnancy and non-pregnant women of childbearing age, while IO was not associated with either isolated TPOAb-positive or isolated TgAb-positive. CLINICAL TRIAL REGISTRATION: ChiCTR-TRC-13003805, http://www.chictr.org.cn/index.aspx.

17.
Chem Commun (Camb) ; 55(77): 11638-11641, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31508611

RESUMO

Hollow-sphere Fe2O3 is synthesized as a lithium-ion battery anode. Current densities for the initial material activation are important, related to electrode stability during cycling. The as-prepared anodes are able to retain 92% capacity after 1000 cycles at 1 A g-1. The full-cells assembled with Fe2O3 anodes and LiFePO4 cathodes exhibit good electrochemical properties.

18.
Oxid Med Cell Longev ; 2019: 1915967, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531180

RESUMO

The study was designed to investigate the chemical composition and antioxidant activities of polysaccharides from Yingshan Cloud Mist Tea. The chemical composition of green tea polysaccharides (GTPS) was analyzed by Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), thermogravimetric (TGA), gas chromatograph (GC), and high-performance gel-permeation chromatography (HPGPC). Then, the antioxidant activities in vitro of GTPS, effects of GTPS on body weight, and the antioxidant activities in chickens were studied. The results showed that GTPS were composed of rhamnose (Rha), arabinose (Ara), xylose (Xyl), mannose (Man), glucose (Glu), and galactose (Gal) in a molar ratio of 11.4 : 26.1 : 1.9 : 3.0 : 30.7 : 26.8 and the average molecular weight was 9.69 × 104 Da. Furthermore, GTPS exhibited obvious capacity of scavenging DPPH radical, hydroxyl radical, and superoxide radical and enhanced the ferric-reducing power in vitro. Last, GTPS significantly increased the body weight of chickens, enhanced the T-AOC, SOD, and GSH-Px level, and decreased the content of MDA in chickens. The results indicated that GTPS might be a kind of natural antioxidant, which had the potential application in feed industry.

19.
Dalton Trans ; 48(39): 14626-14631, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31482935

RESUMO

Three boron-pyridyl-isoindoline-1-one based dyes (B1, B2, and B3) with varied side groups were facilely synthesized. Detailed analyses were carried out concerning the crystal conformation, structure dependent photophysical properties and mechanochromic fluorescence (MCF). The MCF behaviours and solid-state emission were demonstrated to be correlated to the different side groups. Upon grinding, the emission of B1 exhibited little changes, whereas reversible MCF with a distinct colour change was observed for B2 and B3. B3 possessing sterically hindered triphenyl amine (TPA) groups showed the most prominent MCF effect. For instance, mechanical grinding resulted in a red-shift of fluorescence from 600 nm to 650 nm. The electronic and steric effects of the donating substituents were found to play important roles in modulating the intramolecular charge-transfer effect and intermolecular interactions. These sensitively and readily tunable mechano-responsive behaviors of the boron-pyridyl-isoindoline-1-one based dyes make them potential candidates for smart fluorescent materials.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31498061

RESUMO

A Gram-reaction-negative, peach-brown-pigmented, slightly curved-rod-shaped, aerobic, non-motile bacterium, designated GSA243-2T, was isolated from fresh water samples collected from the Chishui River flowing through Maotai, Guizhou, south-west PR China. Phenotypic, chemotaxonomic and genomic traits were investigated. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Rhodoferax. The closest phylogenetic relative was Rhodoferax saidenbachensis ATCC BAA-1852T (98.35 %). The major fatty acids were C16: 0 and C16 : 1ω6c and/or C16 : 1ω7c. The major respiratory quinone was ubiquinone Q-8 and the major polar lipid was phosphatidylethanolamine. Genome sequencing revealed a genome size of 3.67 Mbp and a G+C content of 61.17 mol%. Pairwise-determined whole genome average nucleotide identity values and digital DNA-DNA hybridization values suggested that strain GSA243-2T represents a new species, for which we propose the name Rhodoferaxbucti sp. nov. with the type strain GSA243-2T (=CGMCC 1.16288T=KCTC 62564T).

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