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1.
Int J Mol Sci ; 25(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38892231

RESUMO

Aristolochia contorta Bunge is an academically and medicinally important plant species. It belongs to the magnoliids, with an uncertain phylogenetic position, and is one of the few plant species lacking a whole-genome duplication (WGD) event after the angiosperm-wide WGD. A. contorta has been an important traditional Chinese medicine material. Since it contains aristolochic acids (AAs), chemical compounds with nephrotoxity and carcinogenicity, the utilization of this plant has attracted widespread attention. Great efforts are being made to increase its bioactive compounds and reduce or completely remove toxic compounds. MicroRNAs (miRNAs) and natural antisense transcripts (NATs) are two classes of regulators potentially involved in metabolism regulation. Here, we report the identification and characterization of 223 miRNAs and 363 miRNA targets. The identified miRNAs include 51 known miRNAs belonging to 20 families and 172 novel miRNAs belonging to 107 families. A negative correlation between the expression of miRNAs and their targets was observed. In addition, we identified 441 A. contorta NATs and 560 NAT-sense transcript (ST) pairs, of which 12 NATs were targets of 13 miRNAs, forming 18 miRNA-NAT-ST modules. Various miRNAs and NATs potentially regulated secondary metabolism through the modes of miRNA-target gene-enzyme genes, NAT-STs, and NAT-miRNA-target gene-enzyme genes, suggesting the complexity of gene regulatory networks in A. contorta. The results lay a solid foundation for further manipulating the production of its bioactive and toxic compounds.


Assuntos
Aristolochia , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , MicroRNAs , Metabolismo Secundário , MicroRNAs/genética , MicroRNAs/metabolismo , Aristolochia/genética , Metabolismo Secundário/genética , RNA Antissenso/genética , Genoma de Planta , RNA de Plantas/genética
2.
Molecules ; 29(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542929

RESUMO

The oral delivery strategy of natural anti-oxidant and anti-inflammatory agents has attracted great attention to improve the effectiveness of ulcerative colitis (UC) treatment. Herein, we developed a novel orally deliverable nanoparticle, carboxymethyl chitosan (CMC)-modified astaxanthin (AXT)-loaded nanoparticles (CMC-AXT-NPs), for UC treatment. The CMC-AXT-NPs were evaluated by appearance, morphology, particle size, ζ-potential, and encapsulation efficiency (EE). The results showed that CMC-AXT-NPs were nearly spherical in shape with a particle size of 34.5 nm and ζ-potential of -30.8 mV, and the EE of CMC-AXT-NPs was as high as 95.03%. The CMC-AXT-NPs exhibited preferable storage stability over time and well-controlled drug-release properties in simulated intestinal fluid. Additionally, in vitro studies revealed that CMC-AXT-NPs remarkably inhibited cytotoxicity induced by LPS and demonstrated superior antioxidant and anti-inflammatory abilities in Raw264.7 cells. Furthermore, CMC-AXT-NPs effectively alleviated clinical symptoms of colitis induced by dextran sulfate sodium salt (DSS), including maintaining body weight, inhibiting colon shortening, and reducing fecal bleeding. Importantly, CMC-AXT-NPs suppressed the expression of pro-inflammatory cytokines like TNF-α, IL-6, and IL-1ß and ameliorated DSS-induced oxidative damage. Our results demonstrated the potential of CMC-modified nanoparticles as an oral delivery system and suggested these novel AXT nanoparticles could be a promising strategy for UC treatment.


Assuntos
Quitosana , Colite Ulcerativa , Colite , Nanopartículas , Humanos , Colite Ulcerativa/induzido quimicamente , Quitosana/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Sulfato de Dextrana/efeitos adversos , Colite/tratamento farmacológico , Xantofilas
3.
Phys Chem Chem Phys ; 24(23): 14408-14415, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35642955

RESUMO

Functional microgels have powerful applications, especially due to their quick responsiveness to different external stimuli such as temperature, pH, ionic strength, solvent composition and light. Here, we describe the synthesis of novel dual-responsive poly(N-isopropylacrylamide) (PNIPAM) microgels and demonstrate that, in addition to temperature, light changes their properties. The crosslinks inside the microgels were achieved by the host-guest interactions between the trans azobenzene (transAzo) and ß-cyclodextrin (ßCD) units. transAzo can be photoisomerized to cisAzo which exhibits significant lower binding affinity to ßCD. As a consequence, the crosslink density, and thus several microgel properties, can be controlled by light irradiation. Surprisingly, this irradiation with light can significantly change the volume phase transition temperature (VPTT) by several degrees centigrade, presumably due to the fact that the polar ßCD shields the transAzo bound to it, whereas the unbound cisAzo is rather apolar. As a result, continuous irradiation with specific wavelengths until reaching the respective photostationary state allows for a full control over the VPTT within the physiologically relevant range between 32 °C and 38 °C.


Assuntos
Microgéis , Géis/química , Transição de Fase , Temperatura , Temperatura de Transição
4.
Ecotoxicol Environ Saf ; 207: 111572, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254420

RESUMO

In this work, green tea extracts synthesized nanoscale zero-valent iron/nickel (GT-nZVI/Ni) was prepared and the Cr(VI) contaminated soil column was remediated by GT-nZVI/Ni suspension. The influence factors including the concentration, pH value and flow rate of GT-nZVI/Ni suspension were studied. Under the conditions of pH = 4, concentration of 0.15 g/L and flow rate of 1.25 mL/h, GT-nZVI/Ni suspension had the best reduction and immobilization effect on Cr(VI) in the soil column. Na+ and Ca2+ can promote the immobilization of Cr (VI) in soil, while humic acid weakened the immobilization of Cr (VI). After GT-nZVI/Ni is injected into the soil column, the content of weak acid extractable and reduced chromium is significantly reduced, and the toxic hazard of hexavalent chromium in the soil is greatly reduced. The 1D-CDE model was used to fit the breakthrough curves of Fe(tot), Fe(aq) and Fe(0), and the migration of GT-nZVI/Ni in Cr(VI) contaminated soil was simulated and predicted. Compared with the inert solute Cl-, the breakthrough curves of Fe (tot), Fe (aq) and Fe (0) in Cr (VI) contaminated soil column were significantly lagged, with delay coefficients of 2.465, 2.322 and 3.288, respectively. The reaction of GT-nZVI/Ni with Cr (VI) led to the decrease of Fe mobility. Finally, the outflow concentration of Fe (tot) was 0.064 g/L, and the loss was mainly due to reaction and retention in the soil. About 57.89% of GT-nZVI/Ni was retained in the soil.


Assuntos
Cromo/química , Recuperação e Remediação Ambiental/métodos , Poluentes Químicos da Água/química , Cromo/análise , Poluição Ambiental , Concentração de Íons de Hidrogênio , Ferro/química , Níquel , Solo/química , Poluentes do Solo/análise , Poluentes Químicos da Água/análise
5.
J Mol Cell Cardiol ; 146: 109-120, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717194

RESUMO

Myeloid cell leukemia-1 (Mcl-1) is a structurally and functionally unique anti-apoptotic Bcl-2 protein. While elevated levels of Mcl-1 contribute to tumor cell survival and drug resistance, loss of Mcl-1 in cardiac myocytes leads to rapid mitochondrial dysfunction and heart failure development. Although Mcl-1 is an anti-apoptotic protein, previous studies indicate that its functions extend beyond regulating apoptosis. Mcl-1 is localized to both the mitochondrial outer membrane and matrix. Here, we have identified that Mcl-1 in the outer mitochondrial membrane mediates mitochondrial fission, which is independent of its anti-apoptotic function. We demonstrate that Mcl-1 interacts with Drp1 to promote mitochondrial fission in response to various challenges known to perturb mitochondria morphology. Induction of fission by Mcl-1 reduces nutrient deprivation-induced cell death and the protection is independent of its BH3 domain. Finally, cardiac-specific overexpression of Mcl-1OM, but not Mcl-1Matrix, contributes to a shift in the balance towards fission and leads to reduced exercise capacity, suggesting that a pre-existing fragmented mitochondrial network leads to decreased ability to adapt to an acute increase in workload and energy demand. Overall, these findings highlight the importance of Mcl-1 in maintaining mitochondrial health in cells.


Assuntos
Adaptação Fisiológica , Coração/fisiopatologia , Dinâmica Mitocondrial , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Condicionamento Físico Animal , Estresse Fisiológico , Animais , Núcleo Celular/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Domínios Proteicos
6.
J Org Chem ; 85(23): 15760-15766, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33225705

RESUMO

A solvent-free mechanochemical synthesis for 1,2,6-thiadiazine 1-oxides starting from NH-sulfonimidamides and propargyl ketones has been developed. Lewis acids affect these one-pot aza-Michael-addition/cyclization/dehydration reaction sequences. The photophysical properties of the resulting heterocyclic sulfonimidamide derivatives were characterized.

7.
FASEB J ; 32(3): 1170-1183, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29092903

RESUMO

The microenvironment of pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense fibrotic stroma (desmoplasia) generated by pancreatic cancer-associated fibroblasts (CAFs) derived from pancreatic stellate cells (PSCs) and pancreatic fibroblasts (PFs). Using an unbiased GPCRomic array approach, we identified 82 G-protein-coupled receptors (GPCRs) commonly expressed by CAFs derived from 5 primary PDAC tumors. Compared with PSCs and PFs, CAFs have increased expression of GPR68 (a proton-sensing GPCR), with the results confirmed by immunoblotting, The Cancer Genome Atlas data, and immunohistochemistry of PDAC tumors. Co-culture of PSCs with PDAC cells, or incubation with TNF-α, induced GPR68 expression. GPR68 activation (by decreasing the extracellular pH) enhanced IL-6 expression via a cAMP/PKA/cAMP response element binding protein signaling pathway. Knockdown of GPR68 by short interfering RNA diminished low pH-induced production of IL-6 and enhancement of PDAC cell proliferation by CAF conditioned media. CAFs from other gastrointestinal cancers also express GPR68. PDAC cells thus induce expression by CAFs of GPR68, which senses the acidic microenvironment, thereby increasing production of fibrotic markers and IL-6 and promoting PDAC cell proliferation. CAF-expressed GPR68 is a mediator of low-pH-promoted regulation of the tumor microenvironments, in particular to PDAC cell-CAF interaction and may be a novel therapeutic target for pancreatic and perhaps other types of cancers.-Wiley, S. Z., Sriram, K., Liang, W., Chang, S. E., French, R., McCann, T., Sicklick, J., Nishihara, H., Lowy, A. M., Insel, P. A. GPR68, a proton-sensing GPCR, mediates interaction of cancer-associated fibroblasts and cancer cells.


Assuntos
Fibroblastos Associados a Câncer/patologia , Carcinoma Ductal Pancreático/patologia , Comunicação Celular , Neoplasias Pancreáticas/patologia , Células Estreladas do Pâncreas/patologia , Receptores Acoplados a Proteínas G/metabolismo , Microambiente Tumoral , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pancreáticas/metabolismo , Células Estreladas do Pâncreas/metabolismo , Neoplasias Pancreáticas
8.
J Org Chem ; 84(9): 5790-5802, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-30971085

RESUMO

Designing artificial molecular machines to execute complex mechanical tasks, like coupling rotation and translation to accomplish transmission of motion, continues to provide important challenges. Herein, we demonstrated a novel molecular machine comprising a second-generation light-driven molecular motor and a bistable [1]rotaxane unit. The molecular motor can rotate successfully even in an interlocked [1]rotaxane system through a photoinduced cis-to -trans isomerization and a thermal helix inversion, resulting in concomitant transitional motion of the [1]rotaxane. The transmission process was elucidated via 1H NMR, 1H-1H COSY, HMQC, HMBC, and 2D ROESY NMR spectroscopies, UV-visible absorption spectrum, and density functional theory calculations. This is the first demonstration of a molecular motor to rotate against the appreciably noncovalent interactions between dibenzo-24-crown-8 and N-methyltriazolium moieties comprising the rotaxane unit, showing operational capabilities of molecular motors to perform more complex tasks.

9.
Org Biomol Chem ; 17(10): 2651-2656, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30778484

RESUMO

A highly chemo- and regioselective [4 + 2] formal cycloaddition of (Z)-3-iodo allylic nucleophiles and allenamides catalyzed by palladium is reported. The methodology proceeds under mild reaction conditions and is tolerant of alkyl and aryl functional groups. The SN2' substitution at the proximal C[double bond, length as m-dash]C bond performed against the Heck or SN2 pathway delivered a variety of 2-amino-dihydropyrans and 2-amino-tetrahydropiperidines in moderate to satisfactory yields. The [4 + 2] formal cycloaddition derivatives are convertible to interesting scaffolds 2,6,7,7a-tetrahydropyrano[2,3-b]pyrrole and 2,6,7,7a-tetrahydro-1H-pyrrolo[2,3-b]pyridine derivatives via ring-closing metathesis (RCM) with Grubbs catalyst II.

10.
Appl Opt ; 58(3): 609-615, 2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-30694251

RESUMO

Unobscured reflective optical systems with a wide field of view (FOV) have significant application values. However, the aberration increases with the increase of the system FOV, so a wide FOV system is difficult to design. In this paper, a design method that is effective in achieving off-axis three-mirror systems with ultrawide FOV is proposed. In this method, the system FOV is expanded stepwise in the design process, and the surface optical freeform polynomial terms are extended based on the judgment of image quality and some constraint conditions, and to obtain a prospective ultrawide FOV system. A freeform off-axis three-mirror imaging system with a focal length of 1000 mm, an F-number of 10, and an ultrawide FOV of 80°×4° is designed as an example. This design result shows that the system has a high imaging quality of RMS wavefront error value of 0.040λ(λ=0.633 µm), and it demonstrates that the method is effective in achieving off-axis three-mirror systems with an ultrawide FOV.

11.
Cell Physiol Biochem ; 45(4): 1434-1443, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466783

RESUMO

BACKGROUND/AIMS: Fibroblast growth factor 2 (FGF2) plays a predominant role during angiogenesis in the adventitia and in atherosclerotic plaque. A dilemma exists, however, as to whether angiogenic stimulation by FGF2 for the prevention and treatment of atherogenesis is feasible. The aim of this study is to investigate the effect of the 18-kDa FGF-2 isoform on atherosclerosis progression in high-fat diet-fed apolipoprotein E knockout (ApoE-/-) mice. METHODS: We established a model of atherosclerosis using ApoE and 18-kDa FGF-2 gene double knockout mice. They were randomly divided into three groups depending on the duration of diet: 8 weeks, 12 weeks and 16 weeks. Then, we studied the morphology and inflammatory factor staining in the atherosclerosis plaque of these mice. RESULTS: Knockout of the 18-kDa FGF-2 isoform did not change the metabolic characteristics of the mice. Compared to the control group, knockout of the 18-kDa FGF-2 isoform significantly attenuated atherogenesis, reduced aortic plaques, reduced macrophage infiltration and suppressed oxidative stress in mice fed with a high fat diet at all-time points. CONCLUSIONS: 18-kDa FGF-2 aggravated the inflammatory reaction of atherosclerosis.


Assuntos
Aterosclerose/patologia , Fator 2 de Crescimento de Fibroblastos/genética , Macrófagos/imunologia , Estresse Oxidativo , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Quimiocina CCL2/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Fator 2 de Crescimento de Fibroblastos/deficiência , Genótipo , Lipídeos/sangue , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peso Molecular , Miocárdio/patologia , NADPH Oxidase 4/metabolismo , Isoformas de Proteínas/deficiência , Isoformas de Proteínas/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
12.
Acta Biochim Biophys Sin (Shanghai) ; 50(11): 1158-1165, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30260364

RESUMO

The cluster of differentiation 81 (CD81), a member of the transmembrane 4 superfamily, is primarily found to be expressed in a wide variety of cells including T and B cells of vertebrates as a critical modulator. In the present study, the open reading frame of a CD81 gene homolog (Lja-CD81) was cloned in lamprey, Lampetra japonica, which is 702 bp long and encodes a protein of 233-amino acids. Although Lja-CD81 seems to be close to CD9 molecules in their full-length sequences, Lja-CD81 possesses higher identity to vertebrates' CD81 than to CD9 (including a lamprey CD9) molecules in their large extracellular loops. In addition, it also possesses a myristoylation site (Met-Gly-Val-Glu-Gly-Cys-Leu-Lys) in its N-terminal region which is identical to the N-terminal regions of CD81 molecules. These data suggest that CD9 and CD81 molecules diverged no later than the emergence of jawless vertebrates. The mRNA levels of Lja-CD81 in lymphocytes and supraneural myeloid bodies were up-regulated significantly after stimulation with mixed antigens, and a similar expressional pattern of Lja-CD81 at protein level was also confirmed. Furthermore, Lja-CD81 was found to be co-localized with variable lymphocyte receptor B (VLRB) evenly on the cell membrane of peripheral blood lymphocytes isolated from control group, but they were found to aggregate on one side of the membrane of peripheral blood VLRB+ lymphocytes after stimulation with mixed antigens. All these results indicate that the Lja-CD81 identified in lamprey may play an important role in the immune response of lamprey VLRB+ lymphocytes.


Assuntos
Proteínas de Peixes/imunologia , Lampreias/imunologia , Linfócitos/imunologia , Receptores de Antígenos/imunologia , Tetraspanina 28/imunologia , Sequência de Aminoácidos , Animais , Western Blotting , Clonagem Molecular , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica , Lampreias/genética , Lampreias/metabolismo , Linfócitos/metabolismo , Microscopia Confocal , Receptores de Antígenos/genética , Receptores de Antígenos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Tetraspanina 28/genética , Tetraspanina 28/metabolismo
13.
J Cell Mol Med ; 21(11): 2634-2642, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28631393

RESUMO

Thiazide diuretics are widely used for the management of hypertension. In recent years, it has been actively debated that there is interchangeability of thiazide-type diuretics hydrochlorothiazide and thiazide-like diuretics including indapamide and chlorthalidone for the treatment of hypertension. With the purpose of seeking out the best thiazide diuretic for clinicians, we summarized the existing evidence on the two types of drugs and conducted a meta-analysis on their efficacy in lowering blood pressure and effects on blood electrolyte, glucose and total cholesterol. Twelve trials were identified: five based on the comparison of indapamide versus hydrochlorothiazide and seven based on the chlorthalidone versus hydrochlorothiazide. In the meta-analysis of blood pressure reduction, thiazide-like diuretics seemed to further reduce systolic BP ([95% CI]; -5.59 [-5.69, -5.49]; P < 0.001) and diastolic BP ([95% CI]; -1.98 [-3.29, -0.66]; P = 0.003). Meanwhile, in the analysis of side effects, the incidence of hypokalemia ([95% CI]; 1.58 [0.80, 3.12]; P = 0.19), hyponatremia ([95% CI]; -0.14 [-0.57, 0.30], P = 0.54), change of blood glucose ([95% CI];0.13 [-0.16, 0.41], P = 0.39) and total cholesterol ([95% CI]; 0.13 [-0.16, 0.41], P = 0.39) showed that there is no statistical significant differences between the two groups of drugs. In conclusion, using thiazide-like diuretics is superior to thiazide-type diuretics in reducing blood pressure without increasing the incidence of hypokalemia, hyponatraemia and any change of blood glucose and serum total cholesterol.


Assuntos
Anti-Hipertensivos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Clortalidona/administração & dosagem , Diuréticos/administração & dosagem , Hidroclorotiazida/administração & dosagem , Hipertensão/tratamento farmacológico , Indapamida/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Glicemia/metabolismo , Clortalidona/efeitos adversos , Colesterol/sangue , Diuréticos/efeitos adversos , Humanos , Hidroclorotiazida/efeitos adversos , Hipertensão/sangue , Hipertensão/fisiopatologia , Hipopotassemia/induzido quimicamente , Hipopotassemia/diagnóstico , Hiponatremia/induzido quimicamente , Hiponatremia/diagnóstico , Indapamida/efeitos adversos , Resultado do Tratamento , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
14.
Microb Pathog ; 108: 78-84, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28487228

RESUMO

S-adenosylhomocysteine/Methylthioadenosine nucleosidase (SAHN E.C.3.2.2.9) does not exist in mammalian cells but is essential for methyl recycling in numerous bacterial and protozoan species. Inhibition of this enzyme could limit synthesis of autoinducers of bacterial quorum sensing (QS), and hence, causes reduction in biofilm formation and may attenuate virulence. In this study, sahn deletion mutant of E. coli MG1655, sahn-complemented strain, and SANH-overexpressing strain were established and used to identify the secretion of autoinducer-2 (AI-2) and biofilm formation. The results indicated that deletion of the sahn gene abolished the production of the QS signal AI-2 and biofilm formation in mutant strain MG1655-Δsahn. And the complementation strain MG1655-Δsahn (pET-28a-sahn) showed restored production of AI-2 and biofilm formation, which indicates that the sahn gene plays an important role in bacterial quorum sensing. The recombinant SAHN protein was overexpressed and purified. The enzymatic activity of SAHN was successfully determined by a coupling-enzyme analysis based on xanthine oxidase, with the Vmax and Km of SAHN enzymatic reaction confirmed. Given that sahn is essential for the quorum sensing of both Gram-negative and Gram-positive bacteria, SAHN could be a potential target for wide-spectrum antibiotics.


Assuntos
Biofilmes/crescimento & desenvolvimento , Escherichia coli/metabolismo , Homosserina/análogos & derivados , Lactonas/metabolismo , Purina-Núcleosídeo Fosforilase/metabolismo , Percepção de Quorum/fisiologia , S-Adenosil-Homocisteína/metabolismo , Proteínas de Bactérias/genética , Clonagem Molecular , DNA Bacteriano , Escherichia coli/enzimologia , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Homosserina/metabolismo , Fenótipo , Purina-Núcleosídeo Fosforilase/genética , Proteínas Recombinantes/genética , Deleção de Sequência , Virulência
16.
Chemistry ; 21(8): 3187-92, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25572459

RESUMO

Nature uses hydrogenase enzyme to catalyze proton reduction at pH 7 with overpotentials and catalytic efficiencies that rival platinum electrodes. Over the past several years, [FeFe]-hydrogenase ([FeFe]-H2 ase) mimics have been demonstrated to be effective catalysts for light-driven H2 evolution. However, it remains a significant challenge to realize H2 production by such an artificial photosynthetic system in neutral aqueous solution. Herein, we report a new system for photocatalytic H2 evolution working in a broad pH range, especially under neutral conditions. This unique system is consisted of branched polyethylenimine (PEI)-grafted [FeFe]-H2 ase mimic (PEI-g-Fe2 S2 ), MPA-CdSe quantum dots (MPA=mercaptopropionic acid), and ascorbic acid (H2 A) in water. Due to the secondary coordination sphere of PEI, which has high buffering capacity and stabilizing ability, the system is able to produce H2 under visible-light irradiation with turnover number of 10 600 based on the Fe2 S2 active site in PEI-g-Fe2 S2 . The stability and activity are much better than that of the same system under acidic or basic conditions and they are, to the best of our knowledge, the highest known to date for photocatalytic H2 evolution from a [FeFe]-H2 ase mimic in neutral aqueous solution.


Assuntos
Hidrogênio/química , Hidrogenase/química , Proteínas Ferro-Enxofre/química , Polietilenoimina/química , Biomimética , Concentração de Íons de Hidrogênio , Hidrogenase/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Processos Fotoquímicos , Pontos Quânticos , Água
17.
Zhonghua Yi Xue Za Zhi ; 95(29): 2355-8, 2015 Aug 04.
Artigo em Chinês | MEDLINE | ID: mdl-26711069

RESUMO

OBJECTIVE: To study the relationship between daytime fatigue and hyperarousal in patients with primary insomnia. METHODS: One hundred and sixty eighty patients with primary insomnia as research group and 149 healthy people as control group were recruited during November 2013 to December 2014 in the psychiatry department of the Third Affiliated Hospital, Sun Yat-sen University. The Hyperarousal Scale (HAS), Pre-Sleep Arousal Scale (PSAS), Fatigue scale-14 (FS-14) and a visual analogue scale (VAS) were used to evaluate the symptom of hyperarousal trait, pre-sleep arousal, daytime fatigue and self reported sleep quality respectively. RESULTS: The participants in research group had more severe symptoms of hyperarousal trait [(41.9±9.7) vs (27.6±7.0)], pre-sleep arousal [(42.0±7.3) vs (22.1±4.7)], daytime fatigue [(9.2±3.1) vs (3.0±0.7)] than those in control group. According the multiple linear regressions, the daytime fatigue in research group was positively related not only to sleep quality, but also to hyperarousal trait and pre-sleep arousal. CONCLUSION: Hyperarousal is an important factor which could affect the daytime fatigue in patients with primary insomnia and should be given more attention to.


Assuntos
Nível de Alerta , Fadiga , Distúrbios do Início e da Manutenção do Sono , Humanos
18.
STAR Protoc ; 5(1): 102914, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38386549

RESUMO

Extracellular vesicles (EVs) are secreted by cells under various conditions and can contribute to the disease progression in tissues. Here, we present a protocol to separate small and large EVs from mouse hearts and cardiac tissues collected from patients. We describe steps for utilizing enzymatic digestion for release of EVs from interstitial space followed by differential centrifugation and immunoaffinity purification. The isolated EVs can be used for various experiments to gain insight into their in vivo functions. For complete details on the use and execution of this protocol, please refer to Liang et al. (2023).1.


Assuntos
Vesículas Extracelulares , Humanos , Camundongos , Animais , Coração , Centrifugação
19.
Food Chem X ; 22: 101512, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38883918

RESUMO

In this study, the moderation-excess interaction of epigallocatechin gallate (EGCG) and calcium ions (Ca2+) to the gelation performance of transparent egg white protein (EWP) gel (EWG) was explored. The oxidation of EGCG introduced a yellowish-brown EWG, whereas the weakening of Ca2+ ionic bonds caused a notable reduction in the hardness of EWG, from 120.67 g to 73.57 g. Achieving the optimal EGCG-to-Ca2+ ratio in EWG conferred enhanced water-holding capacity to 86.98%, while an excess of EGCG attributed to the creation of a three-dimensional structure within the void "walls". The elevated presence of EGCG influenced the ionic bonds and hydrophobic interactions, thereby presenting a moderate-excess relationship with sulfhydryl and disulfide bonds, ß-sheet, and α-helical structures. Notably, EGCG reduced the digestibility of EWG to 50.06%, while concurrently fostering the creation of smaller particle sizes. This study provides a scientific basis for the controllable preparation and quality regulation of transparent EWG.

20.
Medicine (Baltimore) ; 103(19): e38017, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728499

RESUMO

Numerous inflammatory indicators have been demonstrated to be strongly correlated with tumor prognosis. However, the association between inflammatory indicators and the prognosis of patients with nasopharyngeal carcinoma (NPC) receiving treatment with programmed death receptor-1 (PD-1) immunosuppressant monoclonal antibodies remains uncertain. Inflammatory indicators in peripheral blood were collected from 161 NPC patients at 3 weeks after initial PD-1 treatment. Through univariate and multivariate analyses, as well as nomogram and survival analyses, we aimed to identify independent prognostic factors related to 1-year progression-free survival (PFS). Subsequently, a prognostic nomogram was devised, and its predictive and discriminating abilities were assessed utilizing calibration curves and the concordance index. Our univariate and multivariate analyses indicated that age (P = .012), M stage (P < .001), and systemic immune-inflammation index (SII) during the third week following initial PD-1 treatment (SII3, P = .005) were independently correlated with the 1-year PFS of NPC patients after PD-1 treatment. Notably, we constructed a novel nomogram based on the SII3, age, and M stage. Importantly, utilizing the derived cutoff point from the nomogram, the high-risk group exhibited significantly shorter PFS than did the low-risk group (P < .001). Furthermore, the nomogram demonstrated a greater concordance index for PFS than did the tumor node metastasis stage within the entire cohort. We successfully developed a nomogram that integrates the SII3 and clinical markers to accurately predict the 1-year PFS of NPC patients receiving PD-1 inhibitor treatment.


Assuntos
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Nomogramas , Humanos , Masculino , Feminino , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/sangue , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/sangue , Adulto , Idoso , Inibidores de Checkpoint Imunológico/uso terapêutico , Prognóstico , Estadiamento de Neoplasias , Intervalo Livre de Progressão , Adulto Jovem
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