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1.
Int J Biol Macromol ; 254(Pt 3): 127835, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37924911

RESUMO

Sagittaria sagittifolia L. polysaccharides possess anti-inflammatory, antioxidant, and immune-modulatory properties. In this study, we identified a novel S. sagittifolia L. polysaccharide, named PSSP-1, and evaluated its potential in alleviating dextran sulfate sodium (DSS)-induced colitis in a mouse model. The results demonstrated that administration of PSSP-1 at doses of 100, 200, and 400 mg/kg·bw significantly reduced the disease activity index (DAI) and suppressed the expression of inflammatory cytokines in UC mice. Furthermore, PSSP-1 treatment upregulated the expression levels of claudin-1, occludin, and ZO-1, and promoted the diversity and abundance of beneficial gut microbiota, including Lactobacillus and Candidatus_Saccharimonas, while reducing the levels of Bacteroidetes and Verrucomicrobiota. Particularly, the Lactobacillus_johnsonii species may play a potentially significant role in modulating colitis. Subsequently, there was a significant increase in the levels of short-chain fatty acids (SCFAs). Additionally, the correlation analyses revealed positive associations between PSSP-1 supplementation and Nitrosospira and Dialister, which are implicated in gut inflammation. Mechanistically, PSSP-1 intervention inhibited the protein phosphorylation of key molecules in the MAPK and NF-κB signaling pathways. Collectively, these findings suggest that PSSP-1 mitigates colitis symptoms by repairing the intestinal barrier, promoting microbial metabolism, and regulating the gut microbiota-MAPK/NF-κB signaling pathways.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Sagittaria , Animais , Camundongos , NF-kappa B , Transdução de Sinais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Modelos Animais de Doenças , Lactobacillus , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Sulfato de Dextrana , Colo , Camundongos Endogâmicos C57BL
2.
Analyst ; 148(23): 5942-5948, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37853759

RESUMO

On the basis of the "seeing is believing" concept and the existing theory of Hg2+ coordination chemistry, for the first time, we innovatively designed and synthesized a visual-volumetric sensor platform with fluorescein and uracil functionalized polyacrylamide hydrogel. Without the aid of any complicated instruments and power sources, the sensor-enabled quantitative µM-level Hg2+ detection Hg2+ by reading graduation on a pipette with the naked eye. The sensor undergoes volumetric response and shows a wide linear response range to Hg2+ (1.0 × 10-6-5.0 × 10-5 mol L-1) with 2.8 × 10-7 mol L-1 as the detection limit. The highly selective (easily distinguished Hg2+ from other common metal ions), rapid response (∼30 min), and acceptable repeatability (RSD < 5% in all cases) demonstrated that the developed sensor is suitable for onsite practical use for the determination of Hg2+ while being low-cost, simple, and portable. The design principles of the obtained materials and the construction techniques and methods of the sensors described in our study provide a new idea for the research and development of smart materials and a series of visual-volumetric sensors for other analytes.

3.
Phytomedicine ; 120: 155064, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37716035

RESUMO

BACKGROUND: Er Miao San (EMS) is an important herbal formula and a representative prescription for the treatment of the downwards flow of damp-heat syndrome. Clinical practice has proven that EMS can effectively treat rheumatoid arthritis (RA). Previous studies have demonstrated that EMS regulates the functions of T cells and dendritic cells and affects the polarization of macrophages. However, it is not clear whether the inhibitory effect of EMS on RA is related to the regulation of abnormal synovial activation and angiogenesis. PURPOSE: The aim of this study was to elucidate the effect and potential mechanisms of EMS on the abnormal activation and angiogenesis of fibroblast-like synoviocytes (FLSs) in RA. METHODS: The effect of EMS on rats with adjuvant arthritis (AA) and MH7A cells was examined by X-ray, haematoxylin-eosin (HE) staining, immunohistochemistry (IHC), ELISA and western blotting. Angiogenesis in AA rats was measured by a small animal ultrasound imaging system, immunofluorescence (IF) analysis and ELISA. An exchange between MH7A cells and HUVECs was induced using conditioned media that mimicked the microenvironment in vivo. CCK-8, western blotting, and scratch healing and Transwell migration assays were used to evaluate the effect of EMS on the Wnt/ß-catenin signaling pathway and angiogenesis in the inflammatory microenvironment of RA. RESULTS: Our results showed that EMS had a protective effect on AA rats. On the one hand, there was a decrease in paw swelling, the arthritis index, organ indices and proinflammatory factor levels, as well as relief of joint damage. On the other hand, blood flow, the number of immature blood vessels and proangiogenic factors were decreased. Furthermore, EMS reduced the expression of the Wnt/ß-catenin signaling pathway in the synovial tissue of AA rats and MH7A cells. In the inflammatory microenvonrment of RA, the results were consistent. CONCLUSION: This study demonstrated that EMS could protect against RA by inhibiting the abnormal activation and angiogenesis of FLSs, and the mechanism may be related to inhibiting the activation of the Wnt/ß-catenin signaling pathway.


Assuntos
Artrite Experimental , Artrite Reumatoide , Sinoviócitos , Animais , Ratos , Via de Sinalização Wnt , Artrite Reumatoide/tratamento farmacológico , Fibroblastos , Membrana Sinovial , Artrite Experimental/tratamento farmacológico
4.
Clin Lab ; 69(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37560861

RESUMO

BACKGROUND: Red blood cell (RBC) transfusion therapy has greatly reduced mortality and morbidity in multiply transfused patients with oncological malignancies. The aim of this study was to underline the necessity of introducing a policy for extended RBC phenotyping of these patients and for the issuing of antigen-matched blood (at least for E antigen). METHODS: Multivariate logistic regression analysis was used to evaluate the associations of age, gender, transfusion history, and various malignancies with the development of red cell alloimmunization. RESULTS: Given the results of antibody identification, we finally obtained 732 cases to be analyzed, designating them as the p group. The respiratory system (231/732; 31.6%), digestive system (273/732; 37.3%), and female reproductive system (127/732; 17.3%) had the three highest alloimmunization rates in the p group. We screened 81 cases from the p group for which antibody screening in our laboratory had historically yielded negative results. Among the 81 cases with antibody seroconversion, anti-E was the most frequently observed antibody (37%). CONCLUSIONS: The results related to multivariate logistic regression analysis of the Rh group indicate that, in contrast to the other variates, transfusion confers a strongly increased risk of Rh blood system-related red cell alloimmunization. To reduce alloimmunization in tumor patients, it will be essential to introduce a policy for extended RBC phenotyping of high-risk patients and for the issuing of antigen-matched blood (at least for E antigen).


Assuntos
Anemia Hemolítica Autoimune , Antígenos de Grupos Sanguíneos , Humanos , Feminino , Antígenos E da Hepatite B , Isoanticorpos , Transfusão de Sangue , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos
5.
Technol Health Care ; 31(6): 2165-2192, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37302054

RESUMO

BACKGROUND: The emergency rescue ability of firefighters is particularly important in the event of major disasters or accidents. Therefore, an assessment of the firefighter-training effectiveness is necessary. OBJECTIVE: This paper aims to achieve a scientific and effective assessment of the firefighter-training effectiveness in China. An assessment method based on human factor parameters and machine learning was proposed. METHOD: The model is constructed by collecting the corresponding human factor parameters such as electrocardiographic signals, electroencephalographic signals, surface electromyographic signals, and photoplethysmographic signals through wireless sensors and using them as constraint indicators. For the problems of weak human factor parameters and high noise proportion, an improved flexible analytic wavelet transform algorithm is used to denoise and extract the corresponding feature values. To overcome the limitations of traditional assessment methods, improved machine learning algorithms are used to comprehensively assess the training effectiveness of firefighters and provide targeted training suggestions. RESULTS: The effectiveness of this study's evaluation method is verified by comparing it with the expert scoring method and considering firefighters from a special fire station in Xhongmen, Daxing District, Beijing, as an example. CONCLUSION: This study can effectively guide the scientific training of firefighters and the method is more objective and accurate than the traditional method.


Assuntos
Bombeiros , Humanos , China , Eletrocardiografia , Aprendizado de Máquina , Fotopletismografia
6.
Medicine (Baltimore) ; 102(14): e33297, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37026911

RESUMO

The effect of various metastases patterns on the prognosis of lung adenocarcinoma (AD) remains unknown. The purpose of our retrospective study is to determine whether various metastases patterns have a prognostic impact on patients with organ metastatic lung AD. Patient data was extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method was chosen for the evaluation of overall survival (OS) rate. Univariable and multivariable Cox regression analyses were conducted to evaluate independent prognostic factors. In the SEER database, 12,228 patients with IV lung AD were retrieved in total. And 78.78% of those patients (9633/12,228) suffered from one of brain, lung, liver or bone metastasis due to disease progression. It was found that the most common site in patients with metastatic lung AD was brain (21.20%), and the least common site of metastasis was liver (3.50%). Patients who suffered single lung metastatic showed relatively good OS, and the median survival time was 11 months (95% CI 0.470-0.516). For those with 2 metastatic sites, data analysis suggested that the median survival times of patients with bone and lung metastasis (10 months; 95% CI 0.469-0.542) were better than others. For those with 3 metastatic sites, data analysis suggested that metastatic pattern had no effect on the OS. Brain is the most common single metastasis site of lung AD. Compared with the other 3 metastatic sites, patients with lung metastasis had better survival results. Deeper knowledge of metastatic patterns will help doctors to better understand the prognosis and formulate more appropriate treatment plans.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias Hepáticas/patologia , Programa de SEER , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia
7.
Int J Biol Sci ; 19(3): 772-788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778128

RESUMO

Xanthine dehydrogenase (XDH) is the rate-limiting enzyme in purine catabolism by converting hypoxanthine to xanthine and xanthine to uric acid. The altered expression and activity of XDH are associated with the development and prognosis of multiple types of cancer, while its role in lung adenocarcinoma (LUAD) remains unknown. Herein, we demonstrated that XDH was highly expressed in LUAD and was significantly correlated with poor prognosis. Though inhibition of XDH displayed moderate effect on the viability of LUAD cells cultured in the complete medium, it significantly attenuated the survival of starved cells. Similar results were obtained in XDH-knockout cells. Nucleosides supplementation rescued the survival of starved LUAD cells upon XDH inhibition, while inhibition of purine nucleoside phosphorylase abrogated the process, indicating that nucleoside degradation is required for the XDH-mediated survival of LUAD cells. Accordingly, metabolic flux revealed that ribose derived from nucleoside fueled key carbon metabolic pathways to sustain the survival of starved LUAD cells. Mechanistically, down-regulation of XDH suppressed unfolded protein response (UPR) and autophagic flux in starved LUAD cells. Inhibition of XDH decreased the level of amino acids produced by autophagic degradation, which was accompanied with down-regulation of mTORC1 signaling. Supplementation of amino acids including glutamine or glutamate rescued the survival of starved LUAD cells upon knockout or inhibition of XDH. Finally, XDH inhibitors potentiated the anti-cancer activity of 2-deoxy-D-glucose that induced UPR and/or autophagy in vitro and in vivo. In summary, XDH plays a crucial role in the survival of starved LUAD cells and targeting XDH may improve the efficacy of drugs that induce UPR and autophagy in the therapy of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Xantina Desidrogenase/genética , Xantina Desidrogenase/metabolismo , Nucleosídeos/metabolismo , Adenocarcinoma de Pulmão/genética , Autofagia/genética , Resposta a Proteínas não Dobradas , Neoplasias Pulmonares/patologia , Xantinas , Nutrientes , Aminoácidos/metabolismo
8.
J Therm Biol ; 112: 103406, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36796882

RESUMO

In order to investigate the influence of gradient cooling acclimation on body mass regulation in tree shrews (Tupaia belangeri), white adipose tissue (WAT) and brown adipose tissue (BAT) in T. belangeri between the control group and gradient cooling acclimation group on day 56 were collected, body mass, food intake, thermogenic capacity, differential metabolites, and related metabolic pathways in WAT and BAT were measured, the changes of differential metabolites were analyzed by non-targeted metabolomics method based on liquid chromatography-mass spectrometry. The results shown that gradient cooling acclimation significantly increased body mass, food intake, resting metabolic rate (RMR), non-shivering thermogenesis (NST), and masses of WAT and BAT. 23 significant differential metabolites in WAT between the gradient cooling acclimation group and the control group, of which the relative contents of 13 differential metabolites were up-regulated and 10 differential metabolites were down-regulated. 27 significant differential metabolites in BAT, of which 18 differential metabolites decreased and 9 differential metabolites increased. 15 differential metabolic pathways in WAT, 8 differential metabolic pathways in BAT, and 4 differential metabolic pathways involved in both WAT and BAT, including Purine metabolism, Pyrimidine metabolism, Glycerol phosphate metabolism, Arginine and proline metabolism, respectively. All of the above results suggested that T. belangeri could use different metabolites of adipose tissue to withstand low temperature environments and enhance their survival.


Assuntos
Tupaia , Tupaiidae , Animais , Tecido Adiposo Marrom/metabolismo , Aclimatação/fisiologia , Termogênese/fisiologia , Tecido Adiposo Branco/metabolismo , Redes e Vias Metabólicas
9.
J Ethnopharmacol ; 307: 116178, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36708884

RESUMO

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Er miao San (EMS) has been shown to have good anti-inflammatory effects and is widely used in the clinical treatment of RA. However, the exact mechanism is not completely understood. AIM OF THE STUDY: The aim of this study was to explore that EMS-containing serum affects M1/M2 polarization of macrophages and may be mediated through the microRNA (miRNA)-33/NLRP3 pathway, thereby elucidating the molecular mechanism of EMS treatment of RA. MATERIALS AND METHODS: We screened for safe concentrations of EMS-containing serum by using CCK-8 measurement. RAW264.7 cells were cultured with lipopolysaccharide (LPS) (100 ng/mL) and interferon-γ (20 ng/mL) for 24 h to induce M1-type macrophages. Adenosine triphosphate (ATP) (5 mM) was added in the last 30 min to activate NLRP3. The content of miR-33 was detected by RT‒qPCR after transfection of the miRNA-33 mimic. The protein expression levels of NLRP3, ASC, caspase-1, Inducible Nitric Oxide Synthase (iNOS) and Arginase-1 (Arg-1) were detected by Western blot. The contents of IL-1ß, IL-10, TNF-α, TGF-ß and IL-18 in serum and cell supernatant were determined by ELISA. The fluorescence intensity of CD86 and CD206 was detected by immunofluorescence. RESULTS: The results showed that EMS-containing serum promoted the protein expression level of Arg-1 and the secretion levels of TGF-ß and IL-10, inhibited the levels of iNOS, IL-1ß and TNF-α, and regulated the balance of pro-inflammatory factors and anti-inflammatory factors. RT‒qPCR results showed that EMS-containing serum could reduce the level of miRNA-33. EMS-containing serum could reduce the expression of NLRP3 inflammasome-related proteins and downregulate the expression levels of IL-1ß and IL-18. These results suggest that EMS exerts its effect on macrophage polarization through the miRNA-33/NLRP3 pathway. CONCLUSION: EMS-containing serum inhibits the activation of the NLRP3 inflammasome by downregulating miRNA-33, thus preventing the polarization of M1-type macrophages.


Assuntos
Artrite Reumatoide , MicroRNAs , Humanos , Artrite Reumatoide/metabolismo , Inflamassomos/metabolismo , Interleucina-10/metabolismo , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos , MicroRNAs/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Medicamentos de Ervas Chinesas
10.
Front Plant Sci ; 13: 862915, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783938

RESUMO

Lotus (Nelumbo nucifera) is a large aquatic plant that accumulates pharmacologically significant benzylisoquinoline alkaloids (BIAs). However, little is known about their biosynthesis and regulation. Here, we show that the two group III WRKY transcription factors (TFs), NnWRKY70a and NnWRKY70b, positively regulate the BIA biosynthesis in lotus. Both NnWRKY70s are jasmonic acid (JA) responsive, with their expression profiles highly correlated to the BIA concentration and BIA pathway gene expression. A dual-luciferase assay showed that NnWRKY70a could transactivate the NnTYDC promoter, whereas NnWRKY70b could activate promoters of the three BIA structural genes, including NnTYDC, NnCYP80G, and Nn7OMT. In addition, the transient overexpression of NnWRKY70a and NnWRKY70b in lotus petals significantly elevated the BIA alkaloid concentrations. Notably, NnWRKY70b seems to be a stronger BIA biosynthesis regulator, because it dramatically induced more BIA structural gene expressions and BIA accumulation than NnWRKY70a. A yeast two-hybrid assay further revealed that NnWRKY70b physically interacted with NnJAZ1 and two other group III WRKY TFs (NnWRKY53b and NnWRKY70a), suggesting that it may cooperate with the other group III WRKYs to adjust the lotus BIA biosynthesis via the JA-signaling pathway. To illustrate the mechanism underlying NnWRKY70b-mediated BIA regulation in the lotus, a simplified model is proposed. Our study provides useful insights into the regulatory roles of WRKY TFs in the biosynthesis of secondary metabolites.

11.
Inflammopharmacology ; 30(4): 1179-1187, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35829941

RESUMO

NIMA-related kinase 7 (NEK7) is a serine/threonine kinase, which is the smallest one in mammalian NEK family. At present, many studies have reported that NEK7 has a physiological role in regulating the cell cycle and promoting the mitotic process of cells. In recent years, an increasing number of studies have proposed that NEK7 is involved in the activation of the NLRP3 inflammasome. Under normal conditions, NEK7 is in a low activity state, while under pathological conditions, NEK7 is abnormally expressed and therefore plays a key role in the progression of multiple tumors and chronic inflammatory diseases. This review will concentrate on the mechanism of NEK7 participates in the process of mitosis and regulates the activation of NLRP3 inflammasome, the aberrant expression of NEK7 in a variety of tumors and chronic inflammatory diseases, and some potential inhibitors, which may provide some new ideas for the treatment of diverse tumors and chronic inflammatory diseases associated with NEK7.


Assuntos
Inflamassomos , Neoplasias , Animais , Humanos , Inflamassomos/metabolismo , Mamíferos/metabolismo , Quinases Relacionadas a NIMA/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neoplasias/tratamento farmacológico , Proteínas Serina-Treonina Quinases
12.
Pharm Biol ; 60(1): 846-853, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35608068

RESUMO

CONTEXT: Er Miao San (EMS) is a formulation that contains Atractylodis Rhizoma and Phellodendri Cortex in 1:1 ratio, and is commonly used to treat rheumatoid arthritis (RA) and other inflammatory diseases. OBJECTIVE: We investigated the mechanism of action and effects of EMS on peritoneal macrophage differentiation in a rat model of adjuvant arthritis (AA). MATERIALS AND METHODS: EMS (3, 1.5 and 0.75 g/kg; once daily) and methotrexate (0.5 mg/kg; once every 3 days) were administered orally from days 21 to 35 after immunisation. Paw swelling and arthritis index were measured; pathological changes in the ankle joint were observed using x-ray and haematoxylin eosin staining. The ratio of CD86/CD206 in macrophages was detected by flow cytometry. Examination of the miRNA-33/NLRP3 signalling pathway was examined by RT-qPCR and western blotting. The levels of cytokines in the serum and cell supernatants were tested by ELISA. RESULTS: EMS significantly reduced the AA index in rats (from 11.0 to 9.3) and pathological changes in the ankle joint (from 3.8 to 1.4). The ratio of CD86/CD206 was reduced, and polarisation to M1 improved (from 0.9 to 0.6) in macrophages of EMS-treated rats. EMS downregulated the miRNA-33/NLRP3 pathway. Furthermore, EMS treatment increased IL-10 and TGF-ß levels in the serum and supernatant of macrophages of AA rats and simultaneously decreased the levels of IL-1ß and TNF-α. DISCUSSION AND CONCLUSIONS: Our results suggest that EMS may reduce macrophage polarisation to the M1 inflammatory phenotype by downregulating the miRNA-33/NLRP3 pathway in AA rats. These findings may provide new insights into the treatment of RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , MicroRNAs , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Ativação de Macrófagos , Macrófagos Peritoneais/metabolismo , MicroRNAs/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos
13.
Nucleic Acids Res ; 50(10): 5757-5771, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35639925

RESUMO

Synechococcus elongatus, formerly known as Anacystis nidulans, is a representative species of cyanobacteria. It is also a model organism for the study of photoreactivation, which can be fully photoreactivated even after receiving high UV doses. However, for a long time, only one photolyase was found in S. elongatus that is only able to photorepair UV induced cyclobutane pyrimidine dimers (CPDs) in DNA. Here, we characterize another photolyase in S. elongatus, which belongs to iron-sulfur bacterial cryptochromes and photolyases (FeS-BCP), a subtype of prokaryotic 6-4 photolyases. This photolyase was named SePhrB that could efficiently photorepair 6-4 photoproducts in DNA. Chemical analyses revealed that SePhrB contains a catalytic FAD cofactor and an iron-sulfur cluster. All of previously reported FeS-BCPs contain 6,7-dimethyl-8-ribityllumazine (DMRL) as their antenna chromophores. Here, we first demonstrated that SePhrB possesses 7,8-didemethyl-8-hydroxy-5-deazariboflavin (8-HDF) as an antenna chromophore. Nevertheless, SePhrB could be photoreduced without external electron donors. After being photoreduced, the reduced FAD cofactor in SePhrB was extremely stable against air oxidation. These results suggest that FeS-BCPs are more diverse than expected which deserve further investigation.


Assuntos
Desoxirribodipirimidina Fotoliase , DNA/química , Reparo do DNA , Desoxirribodipirimidina Fotoliase/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Ferro , Dímeros de Pirimidina/química , Enxofre , Synechococcus , Raios Ultravioleta
14.
Plant Physiol Biochem ; 177: 38-45, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35245773

RESUMO

Lotus (Nelumbo nucifera) was used as model plant in this study to explore its physiology and molecular response upon short-term exposure to silver nano-particles (AgNPs). Accumulation patterns demonstrated a potential uptake of AgNPs by roots and transport to the leaves as a likely key translocation route in lotus. AgNPs exposure was negatively correlated with lotus growth, including germination rate and petiole length in a concentration-dependent manner. Synthesis of chloroplast pigments in lotus leaves was enhanced by low AgNPs concentration, but were inhibited at high concentration. Hydrogen peroxide (H2O2) was detected in lotus leaves after AgNPs treatment. Proline accumulation in lotus leaves was induced with the increase in AgNPs concentration and exposure time. Antioxidant enzyme activities of superoxide dismutase (SOD), peroxidase (POD) as well as catalase (CAT) were enhanced after the first day of AgNPs exposure, but declined with increased exposure time, indicating a time-dependent toxicity of AgNPs. In addition, real-time PCR revealed that two detoxification-related genes, GSH1 and GST, could be activated on the first day of AgNPs exposure, but down-regulated with prolonged AgNPs treatment. Photosynthesis-related RbcS gene was up-regulated, however, no obvious difference in the expression of RbcL was observed after the first day of AgNPs exposure. Moreover, WRKY70a and WRKY70b transcription factors exhibited similar expression patterns, with the highest induction after a 5 mg/L AgNPs exposure on the first day, which decreased with prolonged exposure time. This study provides useful references for further evaluation of the toxic mechanism of AgNPs and their bio-effects on aquatic plants and ecosystems.


Assuntos
Nanopartículas Metálicas , Nelumbo , Prata , Ecossistema , Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Nanopartículas Metálicas/toxicidade , Nelumbo/efeitos dos fármacos , Nelumbo/genética , Prata/toxicidade , Estresse Fisiológico
15.
Mol Biol Evol ; 38(10): 4505-4519, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34175934

RESUMO

UV irradiation induces the formation of cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts in DNA. These two types of lesions can be directly photorepaired by CPD photolyases and 6-4 photolyases, respectively. Recently, a new class of 6-4 photolyases named iron-sulfur bacterial cryptochromes and photolyases (FeS-BCPs) were found, which were considered as the ancestors of all photolyases and their homologs-cryptochromes. However, a controversy exists regarding 6-4 photoproducts only constituting ∼10-30% of the total UV-induced lesions that primordial organisms would hardly survive without a CPD repair enzyme. By extensive phylogenetic analyses, we identified a novel class of proteins, all from eubacteria. They have relatively high similarity to class I/III CPD photolyases, especially in the putative substrate-binding and FAD-binding regions. However, these proteins are shorter, and they lack the "N-terminal α/ß domain" of normal photolyases. Therefore, we named them short photolyase-like. Nevertheless, similar to FeS-BCPs, some of short photolyase-likes also contain four conserved cysteines, which may also coordinate an iron-sulfur cluster as FeS-BCPs. A member from Rhodococcus fascians was cloned and expressed. It was demonstrated that the protein contains a FAD cofactor and an iron-sulfur cluster, and has CPD repair activity. It was speculated that this novel class of photolyases may be the real ancestors of the cryptochrome/photolyase family.


Assuntos
Desoxirribodipirimidina Fotoliase , Criptocromos/genética , Reparo do DNA , Desoxirribodipirimidina Fotoliase/química , Desoxirribodipirimidina Fotoliase/genética , Desoxirribodipirimidina Fotoliase/metabolismo , Filogenia , Dímeros de Pirimidina/química , Dímeros de Pirimidina/metabolismo , Raios Ultravioleta
16.
Opt Express ; 28(26): 39413-39429, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33379491

RESUMO

Super-resolution fluorescence microscopy has proven to be a useful tool in biological studies. To achieve more than two-fold resolution improvement over the diffraction limit, existing methods require exploitation of the physical properties of the fluorophores. Recently, it has been demonstrated that achieving more than two-fold resolution improvement without such exploitation is possible using only a focused illumination spot and numerical post-processing. However, how the achievable resolution is affected by the processing step has not been thoroughly investigated. In this paper, we focus on the processing aspect of this emerging super-resolution microscopy technique. Based on a careful examination of the dominant noise source and the available prior information in the image, we find that if a processing scheme is appropriate for the dominant noise model in the image and can utilize the prior information in the form of sparsity, improved accuracy can be expected. Based on simulation results, we identify an improved processing scheme and apply it in a real-world experiment to super-resolve a known calibration sample. We show an improved super-resolution of 60nm, approximately four times beyond the conventional diffraction-limited resolution.

17.
Small ; 16(45): e2003844, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33078567

RESUMO

Recent studies have shown a correlation between elevated interleukin 6 (IL-6) concentrations and the risk of respiratory failure in COVID-19 patients. Therefore, detection of IL-6 at low concentrations permits early diagnosis of worst-case outcome in viral respiratory infections. Here, a versatile biointerface is presented that eliminates nonspecific adhesion and thus enables immunofluorescence detection of IL-6 in whole human plasma or whole human blood during coagulation, down to a limit of detection of 0.5 pg mL-1 . The sensitivity of the developed lubricant-infused biosensor for immunofluorescence assays in detecting low molecular weight proteins such as IL-6 is facilitated by i) producing a bioink in which the capture antibody is functionalized by an epoxy-based silane for covalent linkage to the fluorosilanized surface and ii) suppressing nonspecific adhesion by patterning the developed bioink into a lubricant-infused coating. The developed biosensor addresses one of the major challenges for biosensing in complex fluids, namely nonspecific adhesion, therefore paving the way for highly sensitive biosensing in complex fluids.


Assuntos
Anticorpos/metabolismo , Técnicas Biossensoriais/métodos , Interleucina-6/sangue , Lubrificantes/química , Microtecnologia , Fluorescência , Imunofluorescência , Humanos , Espectroscopia Fotoeletrônica , Polimetil Metacrilato/química , Padrões de Referência
18.
Appl Opt ; 59(30): 9626-9632, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33104686

RESUMO

Residual stress affects significantly the quality of plastic lenses. In this paper, the influence of process parameters on the residual stress of injection compression molded plastic lenses was investigated by orthogonal simulation. The results show that the effect of compression delay time on residual stress was the most significant, followed by compression distance and compression speed, which are both related to the compression process. Then, the relationship between the residual stress obtained by simulations and the optical path difference measured by the experiment was compared by single factor experiments of four key injection compression molding process parameters. The change trends were similar, which proves that the numerical simulation has the potential to predict the residual stress of plastic lenses and optimize the process parameters, so as to improve their optical quality.

19.
J Biomed Opt ; 25(5): 1-13, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32441065

RESUMO

SIGNIFICANCE: It is commonly assumed that using the objective lens to create a tightly focused light spot for illumination provides a twofold resolution improvement over the Rayleigh resolution limit and that resolution improvement is independent of object properties. Nevertheless, such an assumption has not been carefully examined. We examine this assumption by analyzing the performance of two super-resolution methods, known as image scanning microscopy (ISM) and illumination-enhanced sparsity (IES). AIM: We aim to identify the fundamental differences between the two methods, and to provide examples that help researchers determine which method to utilize for different imaging conditions. APPROACH: We input the same image datasets into the two methods and analyze their restorations. In numerical simulations, we design objects of distinct brightness and sparsity levels for imaging. We use biological imaging experiments to verify the simulation results. RESULTS: The resolution of IES often exceeds twice the Rayleigh resolution limit when imaging sparse objects. A decrease in object sparsity negatively affects the resolution improvement in both methods. CONCLUSIONS: The IES method is superior for imaging sparse objects with its main features being bright and small against a dark, large background. For objects that are largely bright with small dark features, the ISM method is favorable.


Assuntos
Iluminação , Microscopia , Simulação por Computador
20.
Stem Cell Res Ther ; 11(1): 76, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32085799

RESUMO

BACKGROUND: The unmet medical needs in repairing large muscle defects promote the development of tissue regeneration strategy. The use of bioactive molecules in combination with biomaterial scaffold has become an area of great interest. SW033291, a small-molecule inhibitor targeting 15-hydroxyprostaglandin dehydrogenase (15-PDGH) and subsequently elevating the production of prostaglandin E2 (PGE2), has been proved to accelerate the recovery and potentiate the regeneration of multiple tissues including the bone, liver, and colon. The limited understanding of the potential therapeutic effects on myogenesis motivated us to investigate the role of SW033291 in regulating muscle-derived stem cell (MDSC) myogenic differentiation and MDSC-mediated muscle regeneration. METHODS: The characteristics of rat MDSCs, including cell-specific markers and myogenic differentiation potential, were determined. MDSCs were incubated with SW033291 to evaluate PGE2 production and cytotoxicity. The effects of SW033291 on MDSC myogenic differentiation were assessed by quantitative real-time polymerase chain reaction (qPCR), western blot, and immunocytochemistry. The fibrin gel containing MDSCs and SW033291 was used for muscle regeneration in a tibialis anterior muscle defect model. RESULTS: Our data demonstrated that MDSCs were well-tolerated to SW033291 and treatment with SW033291 significantly promoted the production of PGE2 by MDSCs. In vitro analysis showed that SW033291 enhanced the myogenic differentiation and myotube formation by upregulating a series of myogenic markers. Additionally, the activation of PI3K/Akt pathway was involved in the mechanism underlying these promotive effects. Then, in situ casting of fibrin gel containing MDSCs and SW033291 was used to repair the tibialis anterior muscle defect; the addition of SW033291 significantly promoted myofiber formation within the defect region with mild immune response, less fibrosis, and sufficient vascularization. CONCLUSION: SW033291 acted as a positive regulator of MDSC myogenic differentiation, and incorporating the compound with MDSCs in fibrin gel could serve as an effective method to repair large skeletal muscle defects.


Assuntos
Desenvolvimento Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Piridinas/uso terapêutico , Células-Tronco/efeitos dos fármacos , Tiofenos/uso terapêutico , Animais , Diferenciação Celular , Feminino , Humanos , Piridinas/farmacologia , Ratos , Tiofenos/farmacologia
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