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1.
Pharmacol Res ; 193: 106808, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37268177

RESUMEN

Hepatic fibrosis is caused by liver damage as a consequence of wound healing response. Recent studies have shown that hepatic fibrosis could be effectively reversed, partly through regression of activated hepatic stellate cells (HSCs). Transcription factor 21 (TCF21), a member of the basic helix-loop-helix (bHLH) transcription factor, is involved in epithelial-mesenchymal transformation in various diseases. However, the mechanism by which TCF21 regulates epithelial-mesenchymal transformation in hepatic fibrosis has not been elucidated. In this research, we found that hnRNPA1, the downstream binding protein of TCF21, accelerates hepatic fibrosis reversal by inhibiting the NF-κB signaling pathway. Furthermore, the combination of DNMT3a with TCF21 promoter results in TCF21 hypermethylation. Our results suggest that DNMT3a regulation of TCF21 is a significant event in reversing hepatic fibrosis. In conclusion, this research identifies a novel signaling axis, DNMT3a-TCF21-hnRNPA1, that regulates HSCs activation and hepatic fibrosis reversal, providing a novel treatment strategy for hepatic fibrosis. The clinical trial was registered in the Research Registry (researchregistry9079).


Asunto(s)
Cirrosis Hepática , FN-kappa B , Humanos , FN-kappa B/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Transducción de Señal , Células Estrelladas Hepáticas/metabolismo , Metilación de ADN , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
2.
J Am Chem Soc ; 143(44): 18380-18387, 2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34705442

RESUMEN

The pioneering nickel-catalyzed cross-coupling of C-O electrophiles was unlocked by Wenkert in the 1970s; however, the transition-metal-catalyzed asymmetric activation of aromatic C-O bonds has never been reported. Herein the first enantioselective activation of an aromatic C-O bond is demonstrated via the catalytic arylative ring-opening cross-coupling of diarylfurans. This transformation is facilitated via nickel catalysis in the presence of chiral N-heterocyclic carbene ligands, and chiral 2-aryl-2'-hydroxy-1,1'-binaphthyl (ArOBIN) skeletons are delivered axially in high yields with high ee. Moreover, this versatile skeleton can be transformed into various synthetic useful intermediates, chiral catalysts, and ligands by using the CH- and OH-based modifiable sites. This chemistry features mild conditions and good atom economy.

3.
Arch Insect Biochem Physiol ; 84(1): 15-26, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23922278

RESUMEN

The adult behavior and sex pheromone titers of Isoceras sibirica Alpheraky (Lepidoptera, Cossidae) were investigated to determine the diel periodicity of pheromone production during one scotophase and the effect of age on pheromone production. The results showed that females began to call on the first night after eclosion and called mainly during the second half of scotophase. The percentage of females calling was highest in 1- to 3-day-old females and lowest in 4- to 5-day-old females. The onset of scotophase calling occurred earlier as females aged. The responses to the pheromone source of males aged 1-5 days were monitored in a wind tunnel. Peak activity was observed in 3-day-old males, 4 h after the onset of the scotophase. The mating of all 1- to 3-day-old moths began after 6 h in scotophase and some 4- to 5-day-old moths began during the fourth hour. The average duration of copulation was 34.2 ± 18.2 min (N = 45) and ranged from 17.0 to 56.3 min. Gas chromatography-mass spectrometry (GC-MS) analysis of hexane extracts of pheromone glands revealed that the titers of the three sex pheromone components, (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-7-tetradecenyl acetate, and (Z)-9-hexadecadecenyl acetate were very low on the first night after eclosion, increased and peaked on the second night, then decreased with age. During the first 4 h of the scotophase, titers remained invariant, whereas from 4 to 6 h, pheromone titers increased sharply and peaked, with the greatest peak observed in the primary component, Z9-14:Ac. After the peak, all recorded titers declined until they reached a minimum between the ninth and tenth hours of the dark cycle. In field tests, most of the males were captured in traps during 00:00-02:00 h (13 ± 0.48), and females aged 2 days attracted more males than females of other ages. We infer that the I. sibirica mating system is organized around circadian control of mate calling and mating.


Asunto(s)
Mariposas Nocturnas/fisiología , Envejecimiento , Comunicación Animal , Animales , Ritmo Circadiano , Femenino , Masculino , Atractivos Sexuales/metabolismo , Conducta Sexual Animal
4.
J Colloid Interface Sci ; 633: 754-763, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36493741

RESUMEN

Electrocatalytic water splitting in an alkaline medium is recognized as the promising technology to sustainably generate clean hydrogen energy via hydrogen evolution reaction (HER), while the sluggish water dissociation and subsequent *H adsorption steps greatly retarded the reaction kinetics and efficiency of the overall hydrogen evolution process. Whilst nitrogen (N)-doped carbon-based materials are attractive candidates for promoting HER activity, the facile fabrication and gaining a deeper insight into the electrocatalytic mechanism are still challenging. Herein, inspired by the Diels-Alder reaction, we precisely tailored six-membered pyridinic N and five-membered pyrrolic N sites at the edge of the carbon substrates. Comprehensive analysis validates that the participation of pyridinic N (electron-withdrawing) and pyrrolic N (electron-releasing) will induce the charge rearrangements, and further generate local electrophilic and nucleophilic domains in adjacent carbon rings, which guarantees the occurrence of water dissociation to generate protons and the subsequent adsorption of *H intermediates through electrostatic interactions, thereby facilitating the overall reaction kinetics. To this end, the optimal NC-ZnCl2-25 % electrocatalysts present excellent alkaline HER activity (η10 = 45 mV, Tafel slop of 37.7 mV dec-1) superior to commercial Pt/C.


Asunto(s)
Hidrógeno , Protones , Reacción de Cicloadición , Carbono , Nitrógeno , Pirroles , Agua
5.
Front Psychiatry ; 14: 1132666, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113544

RESUMEN

Background: Functional near-infrared spectroscopy (fNIRS) identifies neurophysiological differences between psychiatric disorders by assessing cortical hemodynamic function. Few trials have studied differences in brain functional activity between first-episode medication-naïve depression patients (FMD) and recurrent major depression (RMD). We aimed to determine the differences between FMD and RMD in oxygenated hemoglobin concentration ([oxy-Hb]), and to investigate the correlation between frontotemporal cortex activation and clinical symptoms. Methods: We recruited 40 patients with FMD, 53 with RMD, and 38 healthy controls (HCs) from May 2021 to April 2022. Symptom severity was assessed with the 24-item Hamilton Depression Rating Scale (HAM-D) and the Hamilton Anxiety Rating Scale (HAM-A). A 52-channel fNIRS measured changes in [oxy-Hb] during VFT performance. Results: Both patient groups performed poorly during the VFT task compared with HC (FDR p < 0.05), but there was no significant difference between the two patient groups. Analysis of variance showed that mean [oxy-Hb] activation was lower in both the frontal and temporal lobes in the MDD group compared with HCs (FDR p < 0.05). Additionally, patients with RMD had a significantly lower hemodynamic response in the right dorsolateral prefrontal cortex (DLPFC) and dorsal frontal pole cortex (DFPC) than patients with FMD (FDR p < 0.05). No significant correlation was found between changes in mean [oxy-Hb] and either medical history or clinical symptoms (FDR p < 0.05). Conclusion: The presence of different neurofunctional activity in some of the same brain regions in FMD and RMD patients implied a link between the level of complexity activation in frontal regions and the stage of MDD. Cognitive impairment may already be present at the beginning of an MDD episode. Clinical trial registration: www.chictr.org.cn, identifier ChiCTR2100043432.

6.
Nat Commun ; 13(1): 2953, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35618745

RESUMEN

Nonpolar alkyl moieties, especially methyl group, are frequently used to modify bioactive molecules during lead optimization in medicinal chemistry. Thus transition-metal catalyzed alkylative cross-coupling reactions by using readily available and environmentally benign C-O electrophiles have been established as powerful tools to install alkyl groups, however, the C(sp3)-C(sp2) cross-coupling via asymmetric activation of aromatic C-O bond for the synthesis of alkylated chiral compounds remains elusive. Here, we unlock a C(sp3)-C(sp2) cross-coupling via enantioselective activation of aromatic C-O bond for the efficient synthesis of versatile axially chiral 2-alkyl-2'-hydroxyl-biaryl compounds. By employing a unique chiral N-heterocyclic carbene ligand, this transformation is accomplished via nickel catalysis with good enantiocontrol. Mechanistic studies indicate that bis-ligated nickel complexes might be formed as catalytically active species in the enantioselective alkylative cross-coupling. Moreover, further derivation experiments suggest this developed methodology holds great promise for complex molecule synthesis and asymmetric catalysis.


Asunto(s)
Níquel , Catálisis , Ligandos , Níquel/química , Estereoisomerismo
7.
Z Naturforsch C J Biosci ; 66(9-10): 527-33, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22191219

RESUMEN

We discovered that extracts of the female sex pheromone gland of the carpenterworm moth Isoceras sibirica Alpheraky, a pest of Asparagus officinalis Linn., contained (Z)-7-tetradecen-1-ol (Z7-14:OH), (Z)-9-tetradecen-1-ol (Z9-14:OH), (Z)-7-tetradecenyl acetate (Z7-14:Ac), (Z)-9-tetradecenyl acetate (Z9-14:Ac), and (Z)-9-hexadecadecenyl acetate (Z9-16:Ac). The average levels of the chemicals in a single sex pheromone gland of a calling moth were (0.71 +/- 0.24) ng, (1.42 +/- 0.44) ng, (4.36 +/- 0.32) ng, (8.71 +/- 0.26) ng, and (0.82 +/- 0.38) ng, respectively. The electroantennography (EAG) analysis of these chemicals and their analogues demonstrated that Z9-14:Ac triggered significantly the male EAG response. Traps with rubber septa lure impregnated with Z9-14:Ac (500 microg/septum), Z7-14:Ac (250 microg/septum), and Z9-16:Ac (50 microg/septum) were more effective in catching male moths than traps with other baits or virgin females. Addition of Z7-14:OH and Z9-14:OH to rubber septa did not enhance the efficiency of the trap.


Asunto(s)
Lepidópteros/fisiología , Atractivos Sexuales/análisis , Animales , Femenino , Cromatografía de Gases y Espectrometría de Masas , Masculino , Atractivos Sexuales/química , Atractivos Sexuales/fisiología
8.
Z Naturforsch C J Biosci ; 65(5-6): 403-11, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20653244

RESUMEN

Extracts of female sex pheromone glands of the sand Salix carpenterworm moth, Holcocerus arenicola, a serious pest of desert thicket, were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Based on comparison of retention times and mass spectra of synthetic standards, four compounds were identified as cis-7-tetradecen-1-ol (Z7-14:OH), cis-5-tetradecen-1-yl acetate (Z5-14:OAc), cis-7-tetradecen-1-yl acetate (Z7-14:OAc), and cis-9-hexadecen-1-yl acetate (Z9-16:OAc) with the ratio of 24:39:100:43. Electroantennographic (EAG) analyses of these standard chemicals and their analogues showed that Z7-14:OAc elicited the largest male EAG response, followed by Z5-14:OAc and Z9-16:OAc. In field trials, traps baited with either Z7-14:OAc or Z5-14:OAc captured males while Z7-14:OH-, Z9-16:OAc- or solvent-baited traps caught no males. Z7-14:OAc as a single component was significantly more attractive than Z5-14:OAc alone. The combination of Z7-14:OAc and Z5-14:OAc showed an evidently synergistic effect and attracted much more males than the individual compounds in the field. Addition of Z7-14:OH to the blend of Z7-14:OAc and Z5-14:OAc enhanced slightly the trap catches. We conclude that the major components of the sex pheromone of H. arenicola are Z7-14:OAc and Z5-14:OAc. Currently, a triangle trap baited with the synthetic compounds Z7-14:OAc, Z5-14:OAc, and Z7-14:OH in a 1:0.4:0.25 ratio at 825 microg/trap dosage can be effectively used to monitor the H. arenicola population level and catch the males within the desert regions in China.


Asunto(s)
Lepidópteros/fisiología , Atractivos Sexuales/aislamiento & purificación , Animales , Glándulas Endocrinas/química , Glándulas Endocrinas/fisiología , Femenino , Larva/fisiología , Masculino , Espectrometría de Masas , Pupa/fisiología , Atractivos Sexuales/química , Caracteres Sexuales , Conducta Sexual Animal , Vocalización Animal
9.
Z Naturforsch C J Biosci ; 64(7-8): 590-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19791513

RESUMEN

(Z)-5-dodecen-1-ol (Z5-12:OH), (Z)-5-dodecenyl acetate (Z5-12:Ac), and (Z)-5-tetradecenyl acetate (Z5-14:Ac) were found in the extracts of the female sex pheromone gland of the carpenterworm moth Holcocerus artemisiae Chou et Hua, a pest of Artemisia filifolia. The average amounts of Z5-12:OH, Z5-12:Ac, and Z5-14:Ac in a single sex pheromone gland of a calling moth were (7.14 +/- 0.73) ng, (54.20 +/- 0.34) ng, and (38.70 +/- 0.46) ng, respectively. Electroantennography (EAG) of these compounds and their analogues demonstrated that Z5-12:Ac excitated the largest male EAG response, followed by Z5-14:Ac. Traps baited with rubber septa impregnated with Z5-12:Ac (500 microg/septum) and Z5-14:Ac (300 microg/septum) were more effective than traps with other baits or virgin females. Addition of Z5-12:OH to rubber septa did not enhance the trap catches, but (E,Z)-3,5-dodecadienyl acetate (E3,Z5-12:Ac) enhanced the trap catch.


Asunto(s)
Lepidópteros/fisiología , Atractivos Sexuales/aislamiento & purificación , Acetatos/aislamiento & purificación , Acetatos/metabolismo , Animales , Cromatografía en Capa Delgada , Dodecanol/análogos & derivados , Electrofisiología/métodos , Femenino , Masculino , Mariposas Nocturnas/fisiología , Atractivos Sexuales/biosíntesis , Atractivos Sexuales/química
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 184: 141-150, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28494376

RESUMEN

Heterotrinuclear 3d-4f complexes with a naphthalenediol-based acyclic bis(salamo)-type ligand have been synthesized and structurally characterized. Spectral titrations clearly show that the heterotrinuclear complexes [Zn2(L)La(OAc)3] (1), [Zn2(L)Ce(OAc)3] (2) and [Zn2(L)Dy(OAc)3(CH3OH)]·CH2Cl2 (3) are acquired by the substitution reaction of the obtained homotrinuclear Zn(II) complex with 1 equiv. of Ln(NO3)3 (Ln3+=La3+, Ce3+ and Dy3+). Two Zn(II) ions are penta- and hexa-coordinated with geometries of distorted tetragonal pyramid and octahedron. La(III) ion is deca-coordinated, adopting a distorted bicapped square antiprism geometry. Ce(III) ion is nona-coordinated with geometry of distorted capped square antiprism as well as Dy(III) ion. The different coordination modes of acetate ions in complexes 1, 2 and 3 lead to different coordination numbers of the lanthanide(III) ions. Furthermore, the structures and fluorescence properties have been discussed.

11.
Pest Manag Sci ; 69(10): 1181-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23749472

RESUMEN

BACKGROUND: The oriental fruit moth (OFM) is a worldwide fruit-boring insect pest. In China, OFM monitoring traps use a sex pheromone lure, but their overall design is varied. As such, there is a critical need to develop a standardised OFM trap design. In this field study, ten different trap shapes in varying combinations of colours and sizes (such as trap length and surface area) were examined. RESULTS: The results showed that there was no significant difference in the trapping efficiency between eight colours. The ship-shaped trap could kill more OFM in a short period, whereas the automatic watering basin trap could be more effective in the long run. The optimal trapping diameter of the basin trap was 25 cm. The trapping efficiency of triangle traps with diameters of less than 10 cm was better than that of triangle traps with diameters of over 30 cm. The trapping number of pasteboard traps obviously declined when the surface area increased, and the pasteboard trap with a single board possessed excellent trapping efficiency. CONCLUSION: The results provide useful information for the design of standardised sex pheromone traps for monitoring as well as trapping of OFM in the field.


Asunto(s)
Frutas/parasitología , Control de Insectos/métodos , Mariposas Nocturnas/efectos de los fármacos , Enfermedades de las Plantas/parasitología , Atractivos Sexuales/farmacología , Animales , China , Control de Insectos/instrumentación , Mariposas Nocturnas/fisiología
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(8): 818-22, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-22967336

RESUMEN

OBJECTIVE: To characterize the biological characteristics of natural vectors of Yersinia (Y.) pestis in China. METHODS: Species and genera of natural vectors of Y. pestis in China and their faunal distribution were characterized with modern insect taxonomic techniques. The ecological roles of natural vectors of Y. pestis in natural plague foci were determined according to insect ecological experiments. RESULTS: There were 63 species of natural vectors of Y. pestis including 28 major reservoirs and 35 secondary ones. CONCLUSION: The biology characteristics of major vectors on Y. pestis and their roles in natural plague foci were defined.


Asunto(s)
Reservorios de Enfermedades/microbiología , Insectos Vectores/microbiología , Peste/epidemiología , Animales , China/epidemiología , Ecología , Siphonaptera , Yersinia pestis
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(11): 1144-50, 2012 Nov.
Artículo en Zh | MEDLINE | ID: mdl-23290901

RESUMEN

OBJECTIVE: To group and characterize natural plague foci in China. METHODS: A novel two-class typing method as well as a three-indication nomenclature method were established to group and characterize the natural plague foci, on the basis of eco-geographical landscapes of plague foci, genetics of Yersinia pestis, zoology of rodent reservoirs and the entomology of flea vectors. RESULTS: A total of 12 distinct natural plague foci (including 19 subtypes) as well as their biological features were characterized. CONCLUSION: Natural plague foci in China were grouped and characterized in this study.


Asunto(s)
Geografía , Peste/epidemiología , Roedores/microbiología , Yersinia pestis , Animales , China/epidemiología , Reservorios de Enfermedades , Ecología , Insectos Vectores/microbiología , Peste/microbiología , Siphonaptera/microbiología , Yersinia pestis/genética
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