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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(2): 274-280, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35332729

RESUMEN

Objective: To explore the differences of oral mycobiome and bacteriome between the healthy controls (H) and oral lichen planus (OLP) patients, and the co-occurrence patterns of the salivary mycobiome and bacteriome and the association with host immunity. Methods: Saliva samples were collected from clinical OLP patients (n=35) and healthy volunteers (n=18). Microbiome DNA was extracted for bacterial 16S rRNA genes sequencing and fungal internal transcribed spacer 2 (ITS2) sequencing. Bioinformatics analysis was performed on the data.The levels of IL-17 and IL-23, two pro-inflammatory cytokines, in the saliva were examined, and their correlation with the bacteria was analyzed. Results: There was no significant difference in the overall community structure of the mycobiome and the bacteriome between OLP patients and healthy controls. The abundance of Prevotellaand Solobacterium in the saliva bacteriome was significantly increased in the OLP group (P<0.05), and the relative abundance of Candidaand Aspergillusin the saliva mycobiome was also significantly increased (P<0.05). The co-occurrence pattern of the salivary mycobiome and bacteriome showed that the aforementioned difference was not related. However, the correlation between Aspergillusand bacteria was altered in the H group and the OLP group, and co-occurrence was reduced in the latter group. The level of IL-17 in the saliva was significantly increased in the OLP group. IL-17 and clinical scores were significantly correlated with the abundance of Porphyromonas. Conclusion: The increased abundance of Prevotella, Solobacterium, Candida, and Aspergillus was associated with the pathogenesis of OLP, and the changes of the microbiome co-occurrence relationship and host immunity may be involved in the pathogenesis of OLP.


Asunto(s)
Liquen Plano Oral , Micobioma , Bacterias/genética , Humanos , Liquen Plano Oral/genética , Liquen Plano Oral/patología , ARN Ribosómico 16S/genética , Saliva
2.
Mol Cell Biochem ; 472(1-2): 1-8, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32632609

RESUMEN

Hypoxic-ischemic (HI) brain damage (HIBD) leads to high neonatal mortality and severe neurologic morbidity. Autophagy is involved in the pathogenesis of HIBD. This study aims to investigate the effect of long non-coding RNA colorectal neoplasia differentially expressed (CRNDE) on HIBD and to validate whether autophagy is involved in this process. A HIBD model in rat pups and a HI model in rat primary cerebrocortical neurons were established. Autophagy was evaluated by western blot. The HIBD in rats was evaluated by hematoxylin and eosin staining, TUNEL staining, triphenyl tetrazolium chloride staining, and morris water maze test. The HI injury in vitro was evaluated by determining cell viability and apoptosis. The results showed that CRNDE expression was time-dependently increased in the brain after HIBD. Administration with CRNDE shRNA-expressing lentiviruses alleviated pathological injury and apoptosis in rat hippocampus, decreased infarct volume, and improved behavior performance of rats subjected to HIBD. Furthermore, CRNDE silencing promoted cell viability and inhibited cell apoptosis in neurons exposed to HI. Moreover, CRNDE silencing promoted autophagy and the autophagy inhibitor 3-methyladenine counteracted the neuroprotective effect of CRNDE silencing on HI-induced neuronal injury both in vivo and in vitro. Collectively, CRNDE silencing alleviates HIBD, at least partially, through promoting autophagy.


Asunto(s)
Autofagia , Encéfalo/metabolismo , Hipoxia-Isquemia Encefálica/prevención & control , Neuronas/metabolismo , Fármacos Neuroprotectores , ARN Largo no Codificante/antagonistas & inhibidores , Animales , Animales Recién Nacidos , Conducta Animal , Encéfalo/patología , Hipoxia-Isquemia Encefálica/etiología , Hipoxia-Isquemia Encefálica/patología , Neuronas/patología , ARN Largo no Codificante/genética , Ratas , Ratas Sprague-Dawley
3.
Mol Cell Probes ; 52: 101565, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32234564

RESUMEN

BACKGROUND: This study aimed to test the hypothesis that long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) could exacerbate brain injury caused by intrauterine infection in neonatal rats. METHODS: Intrauterine infection was induced in pregnant rats by lipopolysaccharide (LPS). After delivery, newborn rats with brain injury caused by intrauterine infection were randomly divided into control, control shRNA, and CRNDE shRNA groups. CRNDE expression in serum and amniotic fluid of pregnant rats and neonatal brain tissues were determined by quantitative real-time PCR (qRT-PCR). Morris water maze (MWM) task was used to test the spatial learning and memory ability. Histological examination and apoptosis detection were performed by hematoxylin and eosin (H&E) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, respectively. Immunohistochemistry was conducted to evaluate the activation of astrocytes and microglia. RESULTS: LncRNA CRNDE was highly expressed in serum and amniotic fluid of maternal rats and in brain tissues of offspring rats. Furthermore, shRNA-mediated CRNDE downregulation could rescue the spatial learning and memory ability, improve brain histopathological changes and cell death, and inhibit the activation of astrocytes and microglia caused by LPS. CONCLUSION: CRNDE silencing possessed a cerebral protective effect in neonatal rats with brain injury caused by interauterine infection.


Asunto(s)
Lesiones Encefálicas/etiología , Lesiones Encefálicas/genética , ARN Largo no Codificante/metabolismo , Útero/microbiología , Útero/patología , Animales , Animales Recién Nacidos , Astrocitos/patología , Encéfalo/patología , Lesiones Encefálicas/fisiopatología , Muerte Celular , Citocinas/biosíntesis , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Lipopolisacáridos , Masculino , Memoria , Microglía/patología , Embarazo , ARN Largo no Codificante/genética , Ratas , Aprendizaje Espacial , Regulación hacia Arriba/genética
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 139-145, 2020 Mar.
Artículo en Zh | MEDLINE | ID: mdl-32220178

RESUMEN

Coronavirus disease 2019 (COVID-19) caused by the novel coronavirus, also known as severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), has become a Public Health Emergency of International Concern. Due to the large infection population, broad transmissibility and high mortality, it is urgent to find out the efficient and specific methods to prevent and treat COVID-19. As biological products have broadly applied in the prevention and treatment of severe epidemic diseases, they are promising in blocking novel coronavirus infection. According to the research advances of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), we reviewed the potential application of biological products such as interferon, convalescent plasma, intestinal micro-ecological regulators, vaccines and therapeutic antibodies, etc. , on prevention and treatment of COVID-19. May this review be helpful for conquering COVID-19 in the near future.


Asunto(s)
Betacoronavirus/efectos de los fármacos , Productos Biológicos/uso terapéutico , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Anticuerpos Monoclonales/uso terapéutico , Betacoronavirus/inmunología , COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/terapia , Desarrollo de Medicamentos , Humanos , Inmunización Pasiva , Interferones/uso terapéutico , Coronavirus del Síndrome Respiratorio de Oriente Medio , Pandemias/prevención & control , Plasma , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/prevención & control , SARS-CoV-2 , Síndrome Respiratorio Agudo Grave , Vacunas Virales , Tratamiento Farmacológico de COVID-19 , Sueroterapia para COVID-19
5.
Inflammopharmacology ; 27(6): 1193-1203, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31309485

RESUMEN

Paeoniflorin shows distinct anti-arthritis and immunoregulatory activities, but its rather low bioavailability via oral administration greatly challenges its known mechanism of in vivo activity. Our data showed that oral administration, instead of intraperitoneal injection, of paeoniflorin significantly reduced the polyarthritis index by 44.4%, reduced paw swelling by 18.4% and delayed the onset of arthritis in collagen-induced arthritis (CIA) mice. Oral paeoniflorin treatment also downregulated the systemic pro-inflammatory cytokines IL-6 (by 52.2%), TNF-α (by 57.7%) and IL-1ß (by 34.1%). A pharmacokinetic study revealed that the maximal plasma concentration of paeoniflorin after oral administration was 4.8 ± 1.9 µM in the CIA mice, much lower than the effective concentration in vitro (30 µM). In contrast, paeoniflorin was highly concentrated in the gut content, intestine and Peyer's patches. T cell analysis showed that paeoniflorin markedly reduced transcription factors of Th1 and Th17, inhibited Th1 by 22.2% and 23.1% and Th17 by 43.2% and 25.4% (p < 0.05) in the mesenteric lymph node and Peyer's patches, respectively. Paeoniflorin did not have a significant impact on Th1 and Th17 in the spleen. For the first time, these data suggest that paeoniflorin accumulates in the intestine and primarily modulates Th1 and Th17 responses in the mesenteric lymph nodes and Peyer's patches, rather than in the spleen, to exert anti-arthritis effects.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Glucósidos/farmacología , Mucosa Intestinal/efectos de los fármacos , Ganglios Linfáticos/efectos de los fármacos , Monoterpenos/farmacología , Ganglios Linfáticos Agregados/efectos de los fármacos , Células TH1/efectos de los fármacos , Células Th17/efectos de los fármacos , Animales , Citocinas/biosíntesis , Glucósidos/farmacocinética , Glucósidos/uso terapéutico , Mucosa Intestinal/inmunología , Ganglios Linfáticos/inmunología , Masculino , Ratones , Ratones Endogámicos DBA , Monoterpenos/farmacocinética , Monoterpenos/uso terapéutico , Ganglios Linfáticos Agregados/inmunología , Células TH1/inmunología , Células Th17/inmunología
6.
Acta Pharmacol Sin ; 39(11): 1804-1815, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29921884

RESUMEN

Xuezhikang capsule (XZK) is a traditional Chinese medicine that contains lovastatin (Lv) for hyperlipidemia treatment, although it has fewer side effects than Lv. However, the pharmacokinetic mechanisms contributing to its distinct efficacy and low side effects are unclear. Mice were fed a high-fat diet (HFD) for 6 weeks to induce hyperlipidemia. We first conducted the pharmacokinetic studies in HFD mice following oral administration of Lv (10 mg/kg, i.g.) and found that HFD remarkably decreased the active form of Lv (the lovastatin acid, LvA) exposure in the circulation system, especially in the targeting organ liver, with a declined conversion from Lv to LvA, whereas the Lv (responsible for myotoxicity) exposure in muscle markedly increased. Then we compared the pharmacokinetic profiles of Lv in HFD mice after the oral administration of XZK (1200 mg/kg, i.g.) or an equivalent dose of Lv (10 mg/kg, i.g.). A higher exposure of LvA and lower exposure of Lv were observed after XZK administration, suggesting a pharmacokinetic interaction of some ingredients in XZK. Further studies revealed that HFD promoted the inflammation and inhibited carboxylesterase (CES) activities in the intestine and the liver, thus contributing to the lower transformation of Lv into LvA. In contrast, XZK inhibited the inflammation and upregulated CES in the intestine and the liver. Finally, we evaluated the effects of monacolins and phytosterols, the fractional extracts of isoflavones, on inflammatory LS174T or HepG2 cells, which showed that isoflavones inhibited inflammation, upregulated CES, and markedly enhanced the conversion of Lv into LvA. For the first time, we provide evidence that isoflavones and Lv in XZK act in concert to enhance the efficacy and reduce the side effects of Lv.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Hiperlipidemias/tratamiento farmacológico , Isoflavonas/farmacología , Lovastatina/análogos & derivados , Lovastatina/uso terapéutico , Administración Oral , Animales , Carboxilesterasa/genética , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/metabolismo , Medicamentos Herbarios Chinos/farmacocinética , Humanos , Inflamación/tratamiento farmacológico , Lovastatina/administración & dosificación , Lovastatina/metabolismo , Lovastatina/farmacocinética , Masculino , Ratones Endogámicos C57BL , Receptor X de Pregnano/genética , Regulación hacia Arriba/efectos de los fármacos
7.
Huan Jing Ke Xue ; 44(11): 6159-6171, 2023 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-37973099

RESUMEN

Microplastic-derived dissolved organic matter(MPDOM) during the aging process could be complexed with organic pollutants, heavy metals, and other contaminants and thus affect their migration and transformation. In this study, two types of microplastics, polyethylene terephthalate(PET) and polystyrene(PS), were selected to investigate the spectral properties of MPDOM and their effect on the complexation between MPDOM and sulfadiazine(SDZ)/copper ion(Cu2+) using the fluorescence quenching method, various spectroscopic analysis techniques, and the Ryan-Weber quenching model. The results of UV-vis absorption spectroscopy analysis showed that the molecular weight of the two MPDOMs decreased; the aromaticity and humification increased; and the carboxyl, carbonyl, hydroxyl, and ester substituents on aromatic rings increased after aging. The fluorescence quenching process between MPDOM and SDZ/Cu2+ was static quenching. After quenching, the aromaticity and humification of the two MPDOMs were similar, and the molecular weights were comparable. Combined with three-dimensional fluorescence spectra and parallel factor analysis, two humic-like components and one protein-like component were identified. In addition, the protein-like components of MPDOM reacted preferentially with SDZ and were more sensitive to Cu2+. The results of the Ryan-Weber quenching model revealed that the binding ability of humic-like components to PET-DOM was higher in both SDZ and Cu2+ quenching systems, but the binding ability of MPDOM in the SDZ quenching system was generally stronger than that in the Cu2+ system.

8.
Huan Jing Ke Xue ; 44(12): 6790-6800, 2023 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-38098404

RESUMEN

Fe2+ has been commonly selected to activate peroxydisulfate(PDS) for sulfate radical(SO4-·) generation because of its eco-friendly, cost-effective, and high activity characteristics. However, Fe2+ can be rapidly oxidized to Fe3+ in the reaction, leading to poor utilization of iron for PDS activation. Further, a fairly high concentration of Fe2+ is generally required and may cause iron sludge production and secondary pollution. In this study, a minute Fe2+-activated PDS system induced by bisulfite(BS) was used to degrade paracetamol(APAP) in water. The results showed that the Fe2+-PDS system could be enhanced by the circulation of Fe2+-Fe3+ with the injection of BS and by keeping Fe2+ at a high concentration. Under the optimal conditions(PDS=0.6 mol·L-1; BS=0.4 mol·L-1; Fe2+=10 µmol·L-1; pH=4), 100% APAP(4 µmol·L-1) was removed within 180 s. The degradation rate of APAP increased with the increase in BS(0-0.6 mmol·L-1) and PDS(0.2-1.5 mmol·L-1) concentration, and a modest Fe2+ concentration could accelerate APAP removal. Co-existing substances inhibited the APAP removal and followed the order of HCO3->HPO42->Cl->NO3->humic acid(HA). Based on the quenching experiments and electron paramagnetic resonance spectroscopy test, SO4-· was shown to be the primary reactive species for APAP decomposition in the BS-Fe2+-PDS process. Three-dimensional fluorescence spectroscopy revealed that APAP intermediates had fluorescence characteristics. Moreover, five intermediates were identified, and the probable APAP degradation pathways were proposed. The removal efficiencies of APAP were lower in real waters than that in ultrapure water. Nevertheless, the removal effect was greatly improved after a prolonged reaction time. All results indicated that the BS-Fe2+-PDS system could be a promising method for organic pollutant treatment.

9.
Org Biomol Chem ; 10(5): 970-7, 2012 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-22134414

RESUMEN

The reactions of ß-lactam carbenes with both 3,6-di(2-pyridyl)tetrazine and 3,6-di(4-pyridyl)tetrazine were studied. It was found that ß-lactam carbenes reacted with 3,6-di(2-pyridyl)tetrazine to produce 5-triazolo[1,5-a]pyridylpyrrol-2-ones in good yields, while with 3,6-di(4-pyridyl)tetrazine, they afforded pyrido[c]cyclopenta[b]pyrrol-2-ones in moderate yields. Both reactions were proposed to follow cascade mechanisms containing a 3,6a-dipyridylpyrrolo[3,2-c]pyrazol-5-one intermediate. The different pathways of the transformation of pyrrolo[3,2-c]pyrazol-5-ones were switched by the 2- and 4-pyridyl substituents. This work not only provided a simple and efficient strategy for the construction of novel triazolo[1,5-a]pyridine and pyrido[c]cyclopenta[b]pyrrole derivatives, respectively, but also revealed two different thermal transformation patterns of 3H-pyrazole compounds.

10.
Huan Jing Ke Xue ; 43(10): 4522-4535, 2022 Oct 08.
Artículo en Zh | MEDLINE | ID: mdl-36224138

RESUMEN

Natural colloids (NCs) are ubiquitous in sediments and soils, which could affect the environmental fate of antibiotics. Focusing on chloramphenicol (CAP), different sources of the sediments and soil samples were selected to research the sorption capacity of NCs with different relative molecular weights towards CAP, as well as the impactors, combined with a multi-method approach including cross-flow ultrafiltration, dynamic light scattering, UV-visible absorption spectroscopy, and three-dimensional excitation-emission matrix fluorescence spectroscopy. The results revealed that the low molecular weight (LMW) of NCs was associated with a low autochthonous origin and a higher humification degree. The high molecular weight (HMW) of NCs were mainly terrestrial sources, and the aromatic rings contained more oxygen-containing functional groups such as carboxyl, hydroxyl, and carbonyl groups. Four fluorescence components were identified using the parallel factor analysis model, and the humic-like substances were the primary fluorescent components. Moreover, based on batch experiments, the study investigated the sorption behavior of CAP by the different fractions of the solid samples. The results showed that the sorption processes of CAP were well fitted by the linear model and Freundlich model. The average sorption rate of CAP by the original solid samples and the solid samples with removed organic and inorganic carbon were 4.46%, 3.93%, and 6.61%, respectively, indicating that organic carbon played an important role in the sorption behavior of CAP. The results of the sorption experiments indicated that CAP was more easily adsorbed on the LMW NCs that had a high degree of humification and a more aliphatic chain on the aromatic rings. In addition, tryptophan-like protein substances in NCs showed the inhibiting effect on the sorption progress of CAP. Redundancy analysis indicated that the sorption of CAP by NCs in sediment and soil was mainly related to the source, aromatics, oxygen functional groups on aromatic rings, humification degree, and humic-like substances of NCs.


Asunto(s)
Contaminantes del Suelo , Suelo , Adsorción , Antibacterianos , Carbono/química , Cloranfenicol , Coloides , Sedimentos Geológicos/química , Sustancias Húmicas/análisis , Oxígeno/análisis , Contaminantes del Suelo/análisis , Triptófano
11.
Huan Jing Ke Xue ; 43(2): 847-858, 2022 Feb 08.
Artículo en Zh | MEDLINE | ID: mdl-35075858

RESUMEN

At present, there are few studies on the spectral characteristics of dissolved organic matter (DOM) in the sediments of the Poyang Lake basin. Therefore, excitation-emission matrix spectroscopy (EEMs) technology and ultraviolet-visible spectra combined with the parallel factor analysis (PARAFAC) were applied to investigate the fluorescent components and sources of DOM in sediments from Poyang Lake. The results showed that the DOM in sediments originated from both terrestrial and autochthonous sources with a high humification. Compared with the sub-lakes, the DOM from the main lake was characterized with a higher concentration of colored DOM, larger particle size, and higher aromaticity and humification degree. In addition, four fluorescence components of DOM in sediments were identified by the PARAFAC model, including three humic-like components (C1, C2, and C4) and one protein-like component (C3). The fluorescence intensity of the humic substances in the sub-lakes was higher than those in the main lake. Furthermore, the percentage of fluorescence abundance of C1 was the highest both in the sub-lakes (42%) and main lake (46%). The spatial distribution of the fluorescence intensity of the four components gradually increased from west to east, and the peak values were observed in the Duchang and Nanji Wetland. This may be related to the death of a large number of plants due to the rise in the water level during the wet season and human activities. Principal component analysis showed that although there were no significant differences in the four fluorescent components between the sub-lakes and the main lake, the humification degree of DOM in the sub-lakes was slightly higher than that in the main lake.


Asunto(s)
Lagos , Calidad del Agua , Materia Orgánica Disuelta , Análisis Factorial , Humanos , Sustancias Húmicas/análisis , Lagos/análisis , Espectrometría de Fluorescencia
12.
J Org Chem ; 76(11): 4746-52, 2011 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-21548593

RESUMEN

A study of the nucleophilic addition of ß-lactam carbenes to 3,6-diphenyltetrazines is reported. Instead of the formation of pyrazole derivatives like most reactions between nucleophilic or ambiphilic carbenes and 3,6-disubstituted tetrazines, ß-lactam carbenes reacted with 3,6-diphenyltetrazines to produce indeno[2,1-b]pyrrol-2-ones in good yields. The reaction proceeds most probably through a five-step cascade process. This work has not only provided a one-pot operation for the efficient construction of mutisubstituted indeno[2,1-b]pyrrol-2-ones but also revealed the nucleophilicity of ß-lactam carbenes.

13.
J Org Chem ; 76(18): 7458-65, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-21823590

RESUMEN

The one-pot reaction of ß-lactam carbenes with 2-pyridyl isonitriles followed by an acidic hydrolysis was reported, which produced 2-carbonyl-3-(pyridylamino)imidazo[1,2-a]pyridines in moderate to good yields. Among the resulting novel imidazo[1,2-a]pyridine derivatives, 1-(6-chloro-3-(5-chloropyridin-2-ylamino)imidazo[1,2-a]pyridin-2-yl)-2-ethylbutan-1-one was demonstrated to be an efficient fluorescent probe for mercury ion both in acetonitrile and in buffered aqueous solution.


Asunto(s)
Colorantes Fluorescentes/química , Mercurio/química , Metano/análogos & derivados , Nitrilos/química , Piridinas/química , beta-Lactamas/química , Metano/química
14.
Org Biomol Chem ; 9(7): 2166-74, 2011 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-21293814

RESUMEN

A study on the multicomponent reaction comprising both N-heterocyclic carbenes and substituted phthalaldehydes is reported. The imidazo[1,5-a]pyridine carbenes, namely imidazo[1,5-a]pyridine-3-ylidenes, reacted with phthalaldehydes and DMAD under very mild conditions to produce novel fused tricyclic benzo[d]furo[3,2-b]azepine derivatives. The resulting fused heterocyclic compounds are fluorescent and they give an emission around 500 nm with quantum yields (Φ(F)) being up to 0.81. This study provides not only a unique approach to fused azepine derivatives that are not easily accessible by other methods, but also opens a new avenue to complicated molecular skeletons. The fluorescence properties of long emission wavelength and high fluorescence quantum yields of some products predict their potential applications as optical sensors.

15.
J Org Chem ; 75(19): 6644-52, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20831236

RESUMEN

The facile three-component reactions of N,N-substituted imidazo[1,5-a]pyridine carbenes, namely imidazo[1,5-a]pyridin-3-ylidenes, with aldehydes and DMAD or allenoates were disclosed. Both reactions proceeded via tandem nucleophilic addition, [3 + 2]-cycloaddition, and ring transformation to produce different 4-[(2-pyridyl)methyl]aminofuran derivatives generally in moderate yields. This work not only provided the first example of the application of imidazo[1,5-a]pyridin-3-ylidenes in organic synthesis but also developed a straightforward approach to fully substituted furans that are not easily accessible by other methods.


Asunto(s)
Aldehídos/química , Alquinos/química , Furanos/síntesis química , Metano/análogos & derivados , Naftalenos/química , Piridinas/química , Furanos/química , Metano/química , Estructura Molecular , Estereoisomerismo
16.
Huan Jing Ke Xue ; 38(8): 3192-3199, 2017 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-29964926

RESUMEN

The spectral characteristics of fractionated colloids in wastewaters from Huangpu River were isolated and investigated via cross flow ultrafiltration systems with different molecular mass of membranes and three-dimensional excitation-emission matrix fluorescence spectroscopy. The results showed that the colloidal concentration (CC) and colloidal organic carbon content (COC) of all size fractions in all samples were in the ranges 9.60-32.50 mg·L-1 and 0.03-6.25 mg·L-1, respectively. Moreover, both CC and COC values increased as the colloidal size increased. The protein- (i.e., peaks D and T) and humic-like (peaks C and A) materials were present in all the size fractions (except for the Mr 300×103-1 µm size fraction of the influent sample), of which protein- and humic-like materials were mainly in the Mr 1×103-5×103 and Mr 10×103-300×103 size fractions, respectively. In addition, fluorescence indices (including the fluorescence index (FI), humification index (HIX), and the index of recent autochthonous contribution (BIX)) were introduced to determine the source and spectral characteristic of the selected colloids. These indices indicated that the relatively small colloids with high aromaticity and hydrophobicity mainly originated from terrestrial sources, whereas the relatively large colloids were predominantly from the recent autochthonous organic matter and the protein-like components.

17.
Ying Yong Sheng Tai Xue Bao ; 25(7): 1940-8, 2014 Jul.
Artículo en Zh | MEDLINE | ID: mdl-25345043

RESUMEN

Ardisia violacea is one of the rare and endangered species, and distributes only in Zhejiang and Taiwan Provinces in China. In order to understand the light requirement and adaptability of A. violacea, the effects of different light intensities (shading rate of 90%, 60%, 25%, and the full light) on leaf photosynthetic characteristics and chlorophyll fluorescence of A. violacea were studied. The photosynthetic rate (Pn) and stomatal conductance (g(s)) of A. violacea varied as a bimodal curve with a 'midday depression' phenomenon in full bright light, and as a unimodal curve in the shading treatments. With the increasing shading rate, the Pn and apparent quantum efficiency (AQY) first increased, and then decreased, the light compensation point (LCP) and light saturation point (LSP) decreased, and the g(s), transpiration rate (Tr), original light energy conversion (Fv/Fm) and potential activity of PS II (Fv/Fo) increased. The total quantity of chlorophyll and the carotenoid (Car) content increased, and Chl a/b decreased under shading conditions. When the shading rate was 25%, the specific leaf mass (LMA) and root to shoot (R/T) ratio of A. violacea reached the maximum. A. violacea possessed a strong flexibility to different light environments, suggesting that light could not be the main limiting factor for natural regeneration of A. violacea populations.


Asunto(s)
Ardisia/fisiología , Clorofila/química , Luz , Fotosíntesis , Carotenoides , China , Ambiente , Fluorescencia , Hojas de la Planta/fisiología , Raíces de Plantas , Transpiración de Plantas , Regeneración , Taiwán
18.
Chem Biol Interact ; 185(3): 227-34, 2010 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-20188712

RESUMEN

Quinoxaline 1,4-dioxides (QdNOs) derivatives, the potent synthetic antibacterial group used in food-producing animals, are assumed to have pro-oxidant properties. However, how oxidative stress mediated their adrenal toxicity is far from clear. The aim of this study was to assess the ability of three QdNOs, i.e. olaquindox (OLA), mequindox (MEQ), and cyadox (CYA), to produce reactive oxygen species (ROS) and oxidative cell damage in porcine adrenocortical cells. Multiple approaches such as cell activity assay, biochemical detectation, flow cytometry and fluorescent were used to study the integrated role of ROS homeostasis, mitochondrial redox metabolism and cell apoptosis as well as chemical stability of these drugs. The results showed that OLA and MEQ treatment evoked a significant dose and time-dependent cell damage in adrenocortical cells, well CYA displayed much less toxicity. As for the intracellular ROS production, OLA irritated a persistent and utmost release of ROS while MEQ made a similar but weaker reaction. CYA, however, had a short and unstable release of intracellular ROS. On the other hand, quinoxalinine-2-carboxylie acid (QCA), one of the metabolites of OLA and MEQ, did not cause any significant production of ROS and showed relatively lower toxicity than its parents. Moreover, an imbalance in the redox metabolism and mitochondrial membrane damage has been implicated in adrenal toxicity of QdNOs. ROS scavengers partially reversed QdNOs-induced mitochondrial damage, indicating that mitochondria may be a major target and critical for ROS-mediated cell death. In a word, these results suggested that ROS is a key mediator of QdNOs-induced cell death via mitochondria-dependent pathway in adrenocortical cells. The results provide a mechanism approach in understanding the characterize of adrenal damage caused by QdNOs in vitro, which would in turn, help in designing the appropriate therapeutic strategies of these kind of feed additives.


Asunto(s)
Corteza Suprarrenal/efectos de los fármacos , Quinoxalinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Corteza Suprarrenal/citología , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Mitocondrias/metabolismo , Estructura Molecular , Oxidación-Reducción , Quinoxalinas/química , Porcinos , Factores de Tiempo
19.
Electron. j. biotechnol ; 14(6): 6-6, Nov. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-640523

RESUMEN

Background: Based on the conserved sequences of a known NBS resistance gene, a pair of degenerate primers was designed to amplify the NBS-LRR resistance gene from peanut using PCR and RACE methods. Results: Analyzing the amino acid sequence by BLAST on NCBI, which was deduced from the 1088bp-long gene named PnAG1-2, showed that it had a certain homology with some resistance proteins, among which Arachis cardenasii resistance protein gene had the highest homology (66 percent). Relative quantification PCR analysis indicated that PnAG1-2 gene expresses more in J11 (an A. flavus-resistant variety) than in JH1012 (an A. flavus-susceptible variety) when the harvest time was coming. Conclusions: In this study, the NBS-LRR resistance sequence was successfully cloned from peanut and prokaryotic expression was done on the gene, which provided a foundation for cultivating anti-A. flavus peanut varieties.


Asunto(s)
Arachis/genética , Enfermedades de las Plantas/genética , Genes de Plantas , Inmunidad Innata/genética , ADN Complementario/genética , Clonación Molecular , Biología Computacional , Genoma de Planta , Reacción en Cadena de la Polimerasa/métodos
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