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1.
Angew Chem Int Ed Engl ; : e202406651, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38781352

ABSTRACT

Organic phosphorescent materials are excellent candidates for use in tumor imaging. However, a systematic comparison of the effects of the intensity, lifetime, and wavelength of phosphorescent emissions on bioimaging performance has not yet been undertaken. In addition, there have been few reports on organic phosphorescent materials that specifically distinguish tumors from normal tissues. This study addresses these gaps and reveals that longer lifetimes effectively increase the signal intensity, whereas longer wavelengths enhance the penetration depth. Conversely, a strong emission intensity with a short lifetime does not necessarily yield robust imaging signals. Building upon these findings, an organo-phosphorescent material with a lifetime of 0.94 s was designed for tumor imaging. Remarkably, the phosphorescent signals of various organic nanoparticles are nearly extinguished in blood-rich organs because of the quenching effect of iron ions. Moreover, for the first time, we demonstrated that iron ions universally quench the phosphorescence of organic room-temperature phosphorescent materials, which is an inherent property of such substances. Leveraging this property, both the normal liver and hepatitis tissues exhibit negligible phosphorescent signals, whereas liver tumors display intense phosphorescence. Therefore, phosphorescent materials, unlike chemiluminescent or fluorescent materials, can exploit this unique inherent property to selectively distinguish liver tumor tissues from normal tissues without additional modifications or treatments.

2.
Genetica ; 151(1): 47-59, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36436173

ABSTRACT

Identifying cold-related genes can provide insights into the cold adaptation mechanism of weeping forsythia. In this study, we compared the changes in gene expressions and physiological and biochemical indices under short-term cold stimulation with the changes in gene sequences under a long-term heterogeneous environment to investigate the cold adaptation mechanism in weeping forsythia. The data of adaptive gene sequence changes, e.g., single nucleotide polymorphisms, were obtained from previous landscape genomics studies. The physiological and biochemical indicators and transcriptome results showed that weeping forsythia initiated a series of programs, including increasing cell osmotic pressures, scavenging ROS, activating the defense mechanism that crosses with pathogen infection, and upregulating CBF/DREB1 transcription factor 1, to cope with short-term cold stress. A reanalysis of landscape genomic data suggested that weeping forsythia responded to long-term heterogeneous cold stress by the differentiation of genes related to synthesis of aromatic substances and adenosine triphosphate. Our results supported the hypothesis that the adaptation mechanisms of species to short-term environmental stimulation and long-term stress in heterogeneous environments are different. The differences in cold tolerance among populations are not necessarily obtained by changing cold-responsive gene sequences. This study provides new insights into the cold adaptation mechanisms of plants.


Subject(s)
Forsythia , Forsythia/genetics , Transcriptome , Plants/genetics , Gene Expression Regulation, Plant , Adaptation, Physiological/genetics
3.
J Environ Manage ; 333: 117441, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36753893

ABSTRACT

Water quality safety has attracted global attention and is closely related to the development of the social economy and human health. It is widely recognized that climate change and human activities significantly affect water quality changes. Therefore, quantifying the contributions of factors that drive long-term water quality changes is crucial for effective water quality management. Here, we built a climate-water quality assessment framework (CWQAF) based on climate-water quality response coefficients and trend analysis methods, to achieve this goal. Our results showed that the water quality improved significantly by 4.45%-20.54% from 2011 to 2020 in the Minjiang River basin (MRB). Human activities (including the construction of ecological projects, stricter discharge measures, etc.) were the main driving factors contributing 65%-77% of the improvement effect. Notably, there were differences in the contributions of human activities to water quality parameter changes, such as DO (increase (I): 0.12 mg/L, human contribution (HC): 66.8%), CODMn (decrease (D): 0.71 mg/L, HC: 67.2%), BOD5 (D: 1.10 mg/L, HC: 77.7%), CODCr (D: 4.20 mg/L, HC: 81.2%), TP (D: 0.13 mg/L,HC: 72.8%) and NH3-N (D: 0.40 mg/L, HC: 63.0%). Climate change explained 23%-35% of the variation in water quality. The water quality response to climate change was relatively significant with precipitation. For example, the downstream region was more susceptible to climate change than was the upstream region, as the downstream movement of precipitation centers strengthened the process of climatic factors affecting water quality changes in the MRB. Generally, although human activities were the main driving factor of water quality changes at the basin scale, the contribution of climate change could not be ignored. This study provided a manageable framework for the quantitative analysis of the influence of human activities and climate change on water quality to enable more precise and effective water quality management.


Subject(s)
Environmental Monitoring , Water Quality , Humans , Environmental Monitoring/methods , Climate Change , Human Activities , Rivers , China
4.
Cytokine ; 149: 155721, 2022 01.
Article in English | MEDLINE | ID: mdl-34628128

ABSTRACT

Inflammatory bowel disease (IBD) is a chronic inflammatory disease that affects the small intestine, colon, and rectum. We evaluated associations between the interleukin 10 (IL-10) rs3024505 polymorphism and IBD, ulcerative colitis (UC), and Crohn's disease (CD) by meta-analysis. All peer-reviewed manuscripts concerning the relationship between IL-10_rs3024505 and IBD identified by searing the PubMed, Cochrane Library, EMBASE, and Chinese Medical Database were examined. The association between IL-10_rs3024505 and IBD was evaluated in allele (AG), recessive (RG), dominant (DG), homozygous (HMG), and heterozygous (HTG) genetic models. Associations were also conducted on IBD subtypes, CD and UC, and ethnicity (Non-Europeans and Europeans) subgroups. The meta-analysis included 13 studies, 8552 cases (IBD patients), and 12,830 healthy controls. Subgroup analysis of IBD (UC and CD) revealed heterogeneity in AG, DG, and HTG but no heterogeneity in RG or HMG. Moreover, AG, DG, and HTG did not show publication bias in IBD, CD, or UC, but RG and HMG exhibited publication bias. No heterogeneity and no publication bias were found among the five genetic models by a subgroup analysis of Non-Europeans and European ethnicities. The minor allele(T) of rs3024505 was significantly related to IBD: 1.37 (1.30-1.45) for AG, 2.06 (1.74-2.45) for RG, 1.39 (1.27-1.52) for DG, 2.25 (1.89-2.67) for HMG, and 1.32 (1.23-1.40) for HTG (all P < 0.00001). In the subgroup analysis of ethnicity, there was a significant effect of rs3024505 on IBD in Europeans but not non-Europeans: 1.38 (1.31-1.46) for AG, 2.07 (1.73-2.48) for RG, 1.39 (1.31-1.49) for DG, 2.26 (1.89-2.71) for HMG, and 1.33 (1.24-1.42) for HTG in Europeans (all P < 0.00001). Sensitivity analysis showed no dominant study in Europeans, but one study had a dominant impact in Non-Europeans. In conclusion, IL-10_rs3024505 polymorphism confers susceptibility to CD and UC in Europeans, but its impact should have conducted more studies in Non-Europeans.


Subject(s)
Genetic Predisposition to Disease , Inflammatory Bowel Diseases/genetics , Interleukin-10/genetics , Alleles , Animals , Humans , Polymorphism, Single Nucleotide
5.
Clin Exp Hypertens ; 44(3): 199-207, 2022 Apr 03.
Article in English | MEDLINE | ID: mdl-35014584

ABSTRACT

BACKGROUND: The objective of the present work was to study the anti-hypertensive effect of allisartan on blood pressure (BP) and in facilitating left ventricular remodeling through voltage-gated potassium channels (Kv) 1.5 channels. METHODS: A total of 30 SD rats were randomly divided into sham operation group, hypertension control group, and allisartan treatment group. Hypertension was induced by renal artery stenosis. The animals of treatment group were administered with allisartan once a day at a dose of 30 mg/kg body weight through an oral gavage for 4 weeks. The heart function of animals post 4 weeks of treatment was evaluated by echocardiography, and the degree of ventricular hypertrophy and cardiomyocyte hypertrophy were evaluated by histomorphology. The expression of Kv1.5 is detected by real-time quantitative polymerase chain reaction while Western blotting was used to detect the protein expression. RESULTS: Four weeks after renal artery stenosis, a significant difference was observed in the whole heart ratio, left heart ratio, and cardiomyocyte area between allisartan treatment group and the hypertension control group (P< .01). A significant decrease in BP of allisartan treatment group compared to hypertension control group (P< .01) was observed. The expression of Kv1.5 mRNA was increased significantly (P< .01) in allisartan treatment group compared to hypertension control group. Western blot analysis also confirmed the increased expression of Kv1.5 channel. CONCLUSION: The results showed that allisartan lowers BP and improves left ventricular remodeling through increased expression of Kv1.5 mRNA.


Subject(s)
Hypertension , Hypertrophy, Left Ventricular , Animals , Antihypertensive Agents/pharmacology , Antihypertensive Agents/therapeutic use , Blood Pressure , Hypertension/drug therapy , Hypertrophy, Left Ventricular/drug therapy , Rats , Rats, Sprague-Dawley
6.
Chem Soc Rev ; 50(22): 12616-12655, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34610056

ABSTRACT

Nonconventional luminophores devoid of remarkable conjugates have attracted considerable attention due to their unique luminescence behaviors, updated luminescence mechanism of organics and promising applications in optoelectronic, biological and medical fields. Unlike classic luminogens consisting of molecular segments with greatly extended electron delocalization, these unorthodox luminophores generally possess nonconjugated structures based on subgroups such as ether (-O-), hydroxyl (-OH), halogens, carbonyl (CO), carboxyl (-COOH), cyano (CN), thioether (-S-), sulfoxide (SO), sulfone (OSO), phosphate, and aliphatic amine, as well as their grouped functionalities like amide, imide, anhydride and ureido. They can exhibit intriguing intrinsic luminescence, generally featuring concentration-enhanced emission, aggregation-induced emission, excitation-dependent luminescence and prevailing phosphorescence. Herein, we review the recent progress in exploring these nonconventional luminophores and discuss the current challenges and future perspectives. Notably, different mechanisms are reviewed and the clustering-triggered emission (CTE) mechanism is highlighted, which emphasizes the clustering of the above mentioned electron rich moieties and consequent electron delocalization along with conformation rigidification. The CTE mechanism seems widely applicable for diversified natural, synthetic and supramolecular systems.

7.
Angew Chem Int Ed Engl ; 61(16): e202117368, 2022 Apr 11.
Article in English | MEDLINE | ID: mdl-35037708

ABSTRACT

Compounds bearing aliphatic amines can be emissive under appropriate conditions. However, their ionized counterparts, namely, quaternary ammonium salts (QASs), which are widely used as phase-transfer catalysts, ionic liquids, disinfectants, and surfactants, are known as luminescence quenchers and considered nonemissive. Herein, unprecedented intrinsic fluorescence/phosphorescence dual emissions from various QASs are reported, which can be finely regulated by changing the excitation wavelength, alkyl chain length, counterion, and mechanical stimuli. The bright photoluminescence along with distinct afterglow and tunable multicolor emissions enables the application of QAS solids in advanced multimode anticounterfeiting. This finding refreshes the understanding of QASs and may inspire emerging applications based on the utilization of the intrinsic luminescences of QASs. Furthermore, it opens opportunities for the investigation of QAS-related processes and functions via a photophysical approach and affords strong implications for the fabrication of novel nonconventional luminophores.

8.
Macromol Rapid Commun ; 42(11): e2100036, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33851444

ABSTRACT

Nonaromatic photoluminescent polymers have attracted great attention due to their intriguing photophysical properties and promising implications in optoelectronic and biological areas. The luminescence from these nonconventional luminophores can be well rationalized by the clustering-triggered emission mechanism. Sulfur, although as an n-electron-rich element with big radius, is not been widely utilized in construction of nonconventional luminophores despite of its potential competitiveness in nonaromatic photoluminescent polymers. Herein, the "click" type Michael polyaddition is utilized to construct sulfur-bearing nonconventional luminophores, and two sulfur enriched nonaromatic poly(thioether sulfone)s (PES) are obtained, which demonstrate fluorescence-phosphorescence dual emission. More investigations concerning the monomer of bis(vinylsulfonyl)methane are further proceeded to support acquired results. Finally, the application of explosive detection by the prepared PES is also conducted.


Subject(s)
Luminescence , Polymers , Fluorescence , Sulfides , Sulfur
9.
Geriatr Nurs ; 42(1): 1-7, 2021.
Article in English | MEDLINE | ID: mdl-33197701

ABSTRACT

Migrant older adults are influenced by an accumulation of aging and adversities related to migration. This study aimed to evaluate the effects of psychological resilience and social support on health-related quality of life (HRQOL) among migrant older adults, and examine the mediating effect of psychological resilience between social support and HRQOL. A total of 149 migrant older adults were recruited from five communities in Chongqing, China. Social support and psychological resilience were positively associated with physical and mental HRQOL among migrant older adults. Psychological resilience had a partial mediating effect on the relationship between social support and physical and mental HRQOL. These findings provide a better understanding of how social support and psychological resilience work together to affect HRQOL, and it could guide the interventions to promote HRQOL among migrant older adults in the community.


Subject(s)
Resilience, Psychological , Transients and Migrants , Aged , China , Cross-Sectional Studies , Humans , Quality of Life , Social Support
10.
J Minim Access Surg ; 17(1): 95-97, 2021.
Article in English | MEDLINE | ID: mdl-32964892

ABSTRACT

Bronchogenic cysts are congenital foregut dysplasia that occur mostly in the lungs and mediastinum. Here, we report a rare case of retroperitoneal bronchogenic cyst, the location, relationship to adjacent structures and blood supply of which were determined by computed tomography (CT) recombination technology and resected by laparoscope. The case was a 41-year-old female patient. The patient came to the hospital because of intermittent lumbar back discomfort for 1 month. CT scanning revealed a cystic mass of 3.9 cm × 3.2 cm × 3.0 cm behind the left peritoneum. The mass was close to the left adrenal gland, and a branch artery from the left renal artery was revealed to supply the mass. The cystic mass was excised by laparoscopy and confirmed as bronchogenic cyst on histopathology.

11.
Small ; 16(49): e2005035, 2020 12.
Article in English | MEDLINE | ID: mdl-33169482

ABSTRACT

The rational modulation of the nontraditional intrinsic luminescence (NTIL) of nonconventional luminophores remains difficult, on account of the limited understanding on the structure-property relationships and emission mechanisms. Herein, the effective modulation of NTIL is demonstrated based on a group of nonaromatic anhydrides and imides. Mutual bridging of isolated subgroups effectively promotes intramolecular through-space conjugation (TSC), leading to red-shifted emission, enhanced efficiency, and prolonged persistent room-temperature phosphorescence (p-RTP). The substitution of heteroatoms from oxygen to nitrogen drastically changes the TSC and enhances intermolecular interactions, resulting in enhanced emission efficiency. In addition, upon freezing, compression, or embedding into polymer matrices, the emission intensity and color remain well regulated. These results shed new light on the rational modulation of the NTIL and p-RTP of nonconventional luminophores.

12.
BMC Med Genet ; 21(1): 69, 2020 04 03.
Article in English | MEDLINE | ID: mdl-32245427

ABSTRACT

BACKGROUND: The Houge type of X-linked syndromic mental retardation is an X-linked intellectual disability (XLID) recently recorded in the Online Mendelian Inheritance in Man (OMIM) and only 8 cases have been reported in literature thus far. CASE PRESENTATION: We present two brothers with intractable seizures and syndromic intellectual disability with symptoms consisting of delayed development, intellectual disability, and speech and language delay. The mother was a symptomatic carrier with milder clinical phenotype. Whole exome sequencing identified a small fragment deletion spanning four exons, about 9.5 kilobases (kb) in length in the CNKSR2 gene in the patients. The mutation co-segregation revealed that exon deletions occurred de novo in the proband's mother. CONCLUSION: Although large deletions have been reported, no small deletions have yet been identified. In this case report, we identified a small deletion in the CNKSR2 gene. This study enhances our knowledge of the CNKSR2 gene mutation spectrum and provides further information about the phenotypic characteristics of X-linked syndromic intellectual disability.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Exons/genetics , Mental Retardation, X-Linked/genetics , Sequence Deletion , Child , Child, Preschool , Humans , Intellectual Disability/genetics , Male , Pedigree , Seizures/congenital , Seizures/genetics , Siblings
13.
Chemphyschem ; 21(1): 36-42, 2020 01 03.
Article in English | MEDLINE | ID: mdl-31743552

ABSTRACT

Pure organic room-temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Herein, we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boosts the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5 % is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results will spur the future fabrication of nonconventional phosphors and advance the understanding of the underlying emission mechanism.

14.
BMC Biol ; 17(1): 33, 2019 04 11.
Article in English | MEDLINE | ID: mdl-30975131

ABSTRACT

BACKGROUND: Large animal models, such as the dog, are increasingly being used for studying diseases including gastrointestinal (GI) disorders. Dogs share similar environmental, genomic, anatomical, and intestinal physiologic features with humans. To bridge the gap between commonly used animal models, such as rodents, and humans, and expand the translational potential of the dog model, we developed a three-dimensional (3D) canine GI organoid (enteroid and colonoid) system. Organoids have recently gained interest in translational research as this model system better recapitulates the physiological and molecular features of the tissue environment in comparison with two-dimensional cultures. RESULTS: Organoids were derived from tissue of more than 40 healthy dogs and dogs with GI conditions, including inflammatory bowel disease (IBD) and intestinal carcinomas. Adult intestinal stem cells (ISC) were isolated from whole jejunal tissue as well as endoscopically obtained duodenal, ileal, and colonic biopsy samples using an optimized culture protocol. Intestinal organoids were comprehensively characterized using histology, immunohistochemistry, RNA in situ hybridization, and transmission electron microscopy, to determine the extent to which they recapitulated the in vivo tissue characteristics. Physiological relevance of the enteroid system was defined using functional assays such as optical metabolic imaging (OMI), the cystic fibrosis transmembrane conductance regulator (CFTR) function assay, and Exosome-Like Vesicles (EV) uptake assay, as a basis for wider applications of this technology in basic, preclinical and translational GI research. We have furthermore created a collection of cryopreserved organoids to facilitate future research. CONCLUSIONS: We establish the canine GI organoid systems as a model to study naturally occurring intestinal diseases in dogs and humans, and that can be used for toxicology studies, for analysis of host-pathogen interactions, and for other translational applications.


Subject(s)
Intestines/physiology , Organoids/physiology , Animals , Dog Diseases/physiopathology , Dogs , Gastroenterology , Intestines/physiopathology , Organoids/physiopathology , Stem Cells/cytology , Translational Research, Biomedical
15.
Angew Chem Int Ed Engl ; 59(25): 10018-10022, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32065715

ABSTRACT

Nonaromatic, cross-conjugated, and highly twisted luminogens consisting of acylated succinimides demonstrate aggregation-induced emission characteristics along with tunable multicolor photoluminescence and afterglows in their single crystals. Effective through-space conjugation among different moieties bearing n/π electrons promote the spin-orbit coupling and intersystem crossing and lead to diverse emissive clusters with concurrently rigidified conformations, thus allowing readily tunable emissions. Derived from it, the proof-of-concept application for advanced anti-counterfeiting is illustrated. These results should spur the rational design of novel nonaromatic AIEgens, and moreover advance understandings of the non-traditional intrinsic luminescence and the origin of tunable multicolor afterglows.

16.
J Biol Chem ; 293(43): 16862-16873, 2018 10 26.
Article in English | MEDLINE | ID: mdl-30194283

ABSTRACT

l- to d-residue isomerization is a post-translational modification (PTM) present in neuropeptides, peptide hormones, and peptide toxins from several animals. In most cases, the d-residue is critical for the biological function of the resulting d-amino acid-containing peptide (DAACP). Here, we provide an example in native neuropeptides in which the DAACP and its all-l-amino acid epimer are both active at their newly identified receptor in vitro and at a neuronal target associated with feeding behavior. On the basis of sequence similarity to a known DAACP from cone snail venom, we hypothesized that allatotropin-related peptide (ATRP), a neuropeptide from the neuroscience model organism Aplysia californica, may form multiple diastereomers in the Aplysia central nervous system. We determined that ATRP exists as a d-amino acid-containing peptide (d2-ATRP) and identified a specific G protein-coupled receptor as an ATRP receptor. Interestingly, unlike many previously reported DAACPs and their all-l-residue analogs, both l-ATRP and d2-ATRP were potent agonists of this receptor and active in electrophysiological experiments. Finally, d2-ATRP was much more stable than its all-l-residue counterpart in Aplysia plasma, suggesting that in the case of ATRP, the primary role of the l- to d-residue isomerization may be to protect this peptide from aminopeptidase activity in the extracellular space. Our results indicate that l- to d-residue isomerization can occur even in an all-l-residue peptide with a known biological activity and that in some cases, this PTM may help modulate peptide signal lifetime in the extracellular space rather than activity at the cognate receptor.


Subject(s)
Amino Acids/metabolism , Aplysia/physiology , Insect Hormones/metabolism , Neurons/metabolism , Neuropeptides/metabolism , Peptide Fragments/metabolism , Receptors, G-Protein-Coupled/metabolism , Animals , Neurons/cytology , Protein Processing, Post-Translational , Stereoisomerism
17.
J Virol ; 92(14)2018 07 15.
Article in English | MEDLINE | ID: mdl-29743360

ABSTRACT

Nonenveloped gastrointestinal viruses, such as human rotavirus, can exit infected cells from the apical surface without cell lysis. The mechanism of such nonlytic exit is poorly understood. The nonenveloped Orsay virus is an RNA virus infecting the intestine cells of the nematode Caenorhabditis elegans Dye staining results suggested that Orsay virus exits from the intestine of infected worms in a nonlytic manner. Therefore, the Orsay virus-C. elegans system provides an excellent in vivo model to study viral exit. The Orsay virus genome encodes three proteins: RNA-dependent RNA polymerase, capsid protein (CP), and a nonstructural protein, δ. δ can also be expressed as a structural CP-δ fusion. We generated an ATG-to-CTG mutant virus that had a normal CP-δ fusion but could not produce free δ due to the lack of the start codon. This mutant virus showed a viral exit defect without obvious phenotypes in other steps of viral infection, suggesting that δ is involved in viral exit. Ectopically expressed free δ localized near the apical membrane of intestine cells in C. elegans and colocalized with ACT-5, an intestine-specific actin that is a component of the terminal web. Orsay virus infection rearranged ACT-5 apical localization. Reduction of the ACT-5 level via RNA interference (RNAi) significantly exacerbated the viral exit defect of the δ mutant virus, suggesting that δ and ACT-5 functionally interact to promote Orsay virus exit. Together, these data support a model in which the viral δ protein interacts with the actin network at the apical side of host intestine cells to mediate the polarized, nonlytic egress of Orsay virus.IMPORTANCE An important step of the viral life cycle is how viruses exit from host cells to spread to other cells. Certain nonenveloped viruses can exit cultured cells in nonlytic ways; however, such nonlytic exit has not been demonstrated in vivo In addition, it is not clear how such nonlytic exit is achieved mechanistically in vivo Orsay virus is a nonenveloped RNA virus that infects the intestine cells of the nematode C. elegans It is currently the only virus known to naturally infect C. elegans Using this in vivo model, we show that the δ protein encoded by Orsay virus facilitates the nonlytic exit of the virus, possibly by interacting with host actin on the apical side of worm intestine cells.


Subject(s)
Caenorhabditis elegans/virology , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Nodaviridae/pathogenicity , RNA Virus Infections/virology , Viral Proteins/metabolism , Virus Release , Virus Replication , Animals , Intracellular Signaling Peptides and Proteins/genetics , Membrane Proteins/genetics , RNA Virus Infections/metabolism , Viral Proteins/genetics
18.
PLoS Pathog ; 13(2): e1006231, 2017 02.
Article in English | MEDLINE | ID: mdl-28241071

ABSTRACT

Despite the wide use of Caenorhabditis elegans as a model organism, the first virus naturally infecting this organism was not discovered until six years ago. The Orsay virus and its related nematode viruses have a positive-sense RNA genome, encoding three proteins: CP, RdRP, and a novel δ protein that shares no homology with any other proteins. δ can be expressed either as a free δ or a CP-δ fusion protein by ribosomal frameshift, but the structure and function of both δ and CP-δ remain unknown. Using a combination of electron microscopy, X-ray crystallography, computational and biophysical analyses, here we show that the Orsay δ protein forms a ~420-Å long, pentameric fiber with an N-terminal α-helical bundle, a ß-stranded filament in the middle, and a C-terminal head domain. The pentameric nature of the δ fiber has been independently confirmed by both mass spectrometry and analytical ultracentrifugation. Recombinant Orsay capsid containing CP-δ shows protruding long fibers with globular heads at the distal end. Mutant viruses with disrupted CP-δ fibers were generated by organism-based reverse genetics. These viruses were found to be either non-viable or with poor infectivity according to phenotypic and qRT-PCR analyses. Furthermore, addition of purified δ proteins to worm culture greatly reduced Orsay infectivity in a sequence-specific manner. Based on the structure resemblance between the Orsay CP-δ fiber and the fibers from reovirus and adenovirus, we propose that CP-δ functions as a cell attachment protein to mediate Orsay entry into worm intestine cells.


Subject(s)
Caenorhabditis elegans/virology , Capsid Proteins/ultrastructure , RNA Viruses/physiology , Virus Internalization , Animals , Capsid Proteins/chemistry , Circular Dichroism , Crystallography, X-Ray , Mass Spectrometry , Microscopy, Electron, Transmission , Mutagenesis, Site-Directed , Organisms, Genetically Modified , RNA Virus Infections , RNA Viruses/ultrastructure , Virion/chemistry , Virion/ultrastructure
19.
Water Sci Technol ; 79(6): 1184-1194, 2019 Mar.
Article in English | MEDLINE | ID: mdl-31070598

ABSTRACT

In this study, Eriochrome Black T (EBT) in water was decolorized by means of argon atmospheric pressure plasma jet (APPJ), which showed great decolorization performance. The results showed that the relatively high decolorization rate (approximately 80%) was obtained after plasma treatment for 6 min. Changes to some reactive oxygen and nitrogen species (RONS) in the liquid phase were detected. The contents of peroxide, HO·, O2 -·, and NO· in the plasma-treated EBT solution were much less than those in the activated water. The roles of H2O2 and HO· in the decolorization of EBT solution were explored by evaluating the effects of their scavengers, and by exploring the direct effect of H2O2. The results indicated that reactive oxygen species (ROS), especially HO· and O2 -·, played significant roles in the decolorization of the EBT solution. Analysis of degradation by-products indicated that plasma discharge could destroy the azo bond first and gradually break the aromatic rings of EBT molecules into small molecular compounds.


Subject(s)
Atmospheric Pressure , Azo Compounds/chemistry , Hydrogen Peroxide , Water Pollutants, Chemical/chemistry , Water Purification/methods , Azo Compounds/analysis , Nitrogen , Water Pollutants, Chemical/analysis
20.
Angew Chem Int Ed Engl ; 58(36): 12667-12673, 2019 09 02.
Article in English | MEDLINE | ID: mdl-31243877

ABSTRACT

It is a textbook knowledge that protein photoluminescence stems from the three aromatic amino acid residues of tryptophan(Trp), tyrosine (Tyr), and phenylalanine (Phe), with predominant contributions from Trp. Recently, inspired by the intrinsic emission of nonaromatic amino acids and poly(amino acids) in concentrated solutions and solids, we revisited protein light emission using bovine serum albumin (BSA) as a model. BSA is virtually nonemissive in dilute solutions (≤0.1 mg mL-1 ), but highly luminescent upon concentration or aggregation, showing unique concentration-enhanced emission and aggregation-induced emission (AIE) characteristics. Notably, apart from well-documented UV luminescence, bright blue emission is clearly observed. Furthermore, persistent room-temperature phosphorescence (p-RTP) is achieved even in the amorphous solids under ambient conditions. This visible emission can be rationalized by the clustering-triggered emission (CTE) mechanism. These findings not only provide an in-depth understanding of the emissive properties of proteins, but also hold strong implications for further elucidating the basis of tissue autofluorescence.

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