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1.
Ying Yong Sheng Tai Xue Bao ; 33(8): 2121-2128, 2022 Aug.
Artículo en Chino | MEDLINE | ID: mdl-36043818

RESUMEN

To assess the dynamics and spectral characteristics of dissolved organic matter of twig litter in continuous increase stage, peak stage, and continuous decrease stage of twig litter production in different types of Castanopsis carlesii forest in middle subtropical China, a field experiment was conducted in C. carlesii natural forest, secondary forest and plantation. The results showed that litter production stage and forest type significantly affected the content and spectral characteristics of dissolved organic matter of twig litter were . Compared with the secondary forest and plantation, natural forest had higher dissolved organic carbon (DOC) content and lower special ultraviolet-visible absorption values at 254, 260 and 280 nm (SUVA254, SUVA260, SUVA280) at the continuous decrease stage of twig litter production, indicating high twig litter quality of natural forest and high cycling efficiency with dissolved organic matter in the natural forest at this stage. In contrast, the higher contents of total nitrogen (TN), total phosphorus (TP), total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), and lower DOC:TDP and TDN:TDP ratios of twig litter in the plantation were observed at the peak stage of twig litter production, while no differences were detected in dissolved organic matter contents and spectral values in the secondary forest among the stages. In addition, the DOC, TDN, TDP of twig litter were negatively correlated with temperature and precipitation in the natural forests and secondary forests, but TDN and TDP of twig litter were positively correlated with temperature and precipitation in the plantations. These results suggested that the higher nutrient content at the peak stage of twig litter production in the C. carlesii plantation might lead to more efficient material cycling and that there would be a higher efficiency of material cycling for twig litter dissolved organic matter in C. carlesii natural forest at reduction stage of twig litter production.


Asunto(s)
Materia Orgánica Disuelta , Fagaceae , Carbono/análisis , China , Proteínas de Unión al ADN , Bosques , Nitrógeno/análisis , Fósforo , Suelo
2.
Org Biomol Chem ; 13(3): 817-24, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25407091

RESUMEN

Amides and ketones were intramolecularly coupled in the presence of KOt-Bu/DMF. The reaction provided good yields of a variety of isoquinolinones. A reaction mechanism of radical addition and subsequent E2-elimination is proposed.


Asunto(s)
Amidas/química , Cetonas/química , Quinolonas/síntesis química , Catálisis , Estructura Molecular , Quinolonas/química , Estereoisomerismo , Factores de Tiempo
3.
Org Lett ; 15(23): 6018-21, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24256568

RESUMEN

A new synthesis of indole derivatives has been achieved through intramolecular dehydrative coupling of tertiary amines and ketones promoted by KO-t-Bu/DMF. The reaction probably proceeds via an α-amino alkyl radical pathway.


Asunto(s)
Aminas/química , Indoles/síntesis química , Catálisis , Técnicas Químicas Combinatorias , Indoles/química , Cetonas/química , Estructura Molecular
4.
Chem Commun (Camb) ; 49(93): 10974-6, 2013 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-24132170

RESUMEN

Nitrogen heterocycles could be prepared in good yields via intramolecular cyclization of tertiary amines and alkenes promoted by KOt-Bu-DMF.


Asunto(s)
Alquenos/química , Aminas/química , Butanoles/química , Catálisis , Ciclización , Dimetilformamida/química , Isoquinolinas/síntesis química , Isoquinolinas/química
5.
Org Lett ; 15(10): 2394-7, 2013 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-23621093

RESUMEN

Unprecedented constructions of C═C double bonds have been achieved by Ir-catalyzed intramolecular dehydrogenative and dehydrative cross-coupling of tertiary amines and ketones. The reactions are proposed to proceed via an Ir-mediated C-H activation mechanism.


Asunto(s)
Aminas/química , Iridio/química , Cetonas/química , Catálisis , Estructura Molecular
6.
Dongwuxue Yanjiu ; 34(6): 574-81, 2013 Dec.
Artículo en Chino | MEDLINE | ID: mdl-24415689

RESUMEN

Periods of restricted food intake that lead to lower body weight are often followed by rapid regaining of the lost weight after ad libitum refeeding, an event generally known as the "compensatory growth". To explore the physiological mechanisms underlying "compensatory growth", we evaluated a series of energetic parameters (energy intake, energy expenditure, body composition and serum leptin levels) of adult KM mice subjected to three cycles of stochastic food restriction following by ad libitum refeeding (SFR-Re). The results indicated that animals lost their body mass after stochastic food restriction and then regained to the control level after refeeding. After the final cycle, SFR-Re mice showed higher basal metabolic rate, lower nonshivering thermogenesis, and their cytochrome c oxydase activities, as well as uncoupling protein 1(UCP1) contents of brown adipose tissue all decreased compared with controls. Meanwhile, higher energy intake and digestibility, as well as heavier fat pads also were found in SFR-Re mice. But, serum leptin levels showed no difference between SFR-Re and control mice. On the whole, these findings indicated that when food is resourceful, SFR-Re mice are under rapid "compensatory growth" by increasing their food intake and energy storage efficiency, meanwhile, decreasing energy consumption in thermogenesis. Moreover, leptin may be a possible player in the regulations of energy budget and thermogenesis during "compensatory growth".


Asunto(s)
Peso Corporal , Ingestión de Energía , Leptina/metabolismo , Ratones/crecimiento & desarrollo , Ratones/metabolismo , Animales , Metabolismo Basal , Ingestión de Alimentos , Canales Iónicos/metabolismo , Masculino , Proteínas Mitocondriales/metabolismo , Termogénesis , Proteína Desacopladora 1
7.
Fa Yi Xue Za Zhi ; 29(5): 360-4, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24466777

RESUMEN

OBJECTIVE: To investigate SNP and distribution of haplotypes in differentially methylated region (DMR) upstream of H19 gene in Chinese Korean nationality in order to provide basic data for forensic application and population genetics research. METHODS: One hundred and one blood samples from unrelated Chinese Korean individuals and 14 blood samples from 5 Chinese Korean intergenerational families which known genetic relationship were collected. The SNP in DMR upstream of H19 gene were investigated by PCR-cycle sequencing and McrBC digestion followed by PCR. The haplotypes detected by parentally imprinted allele (PIA) method and relevant genetic parameters were calculated. RESULTS: Thirteen SNPs (rs10840167, rs2525883, rs12417375, rs4930101, rs2525882, rs2735970, rs2735971, rs11042170, rs2735972, rs10732516, rs2071094, rs2107425, and rs4930098) and five haplotypes were detected in 1 174 bp target product in DMR upstream of H19 gene, with 9 SNPs having high discrimination power as good genetic markers. The average gene diversity (GD) of haplotypes was 0.714. The maternal haplotype was confirmed correctly by PIA method from McrBC-digested products of genomic DNA. CONCLUSION: High polymorphisms exist in DMR upstream of H19 gene in Chinese Korean nationality. And determination of the maternal haplotype could furthermore enhance the forensic identification efficiency of imprinted gene.


Asunto(s)
Pueblo Asiatico/genética , Metilación de ADN , Haplotipos , Polimorfismo de Nucleótido Simple , ARN Largo no Codificante/genética , China , ADN/sangre , ADN/genética , Cartilla de ADN , Genética Forense/métodos , Frecuencia de los Genes , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , República de Corea/etnología , Análisis de Secuencia de ADN
8.
Org Biomol Chem ; 10(27): 5245-52, 2012 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-22684421

RESUMEN

An organocatalytic three-component reaction of isatins, malononitrile and isocyanoacetates provided 3,3'-dihydropyrryl-spirooxindoles in excellent yields and enantioselectivities. The products could be readily converted to valuable 3,3'-pyrrolidinyl-spirooxindoles.


Asunto(s)
Indoles/síntesis química , Pirroles/química , Compuestos de Espiro/síntesis química , Productos Biológicos/química , Catálisis , Hidroxilación , Modelos Moleculares , Estructura Molecular , Oxindoles , Estereoisomerismo
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(9): 2346-9, 2011 Sep.
Artículo en Chino | MEDLINE | ID: mdl-22097824

RESUMEN

The novel beta-diketone 1-(4-bromophenyl)-3-phenylpropane-1, 3-dione (L) was synthesized at room temperature by classical Claisen condensation reaction. With the beta-diketone L as the first ligand and phen as the secondary ligand, and a new rare-earth Eu (III) ternary complex was prepared. The ligand L and ternary complex were characterized by elemental analysis, IR spectra, UV spectra and fluorescence spectra. IR spectra indicated that: the novel ligand L contained the structure of beta-diketone, where the content of enol was high; the Eu3+ ion in the ternary complex was coordinated with six oxygen atoms of three L ligands and two nitrogen atoms of the second ligand phen. UV spectra showed that the main absorption was from the first ligand L in the Eu (III) ternary complex. The excitation and emission spectra of the ternary complex were measured and investigated. Fluorescence spectra demonstrated that the ternary complex could emit characteristic fluorescence of rare earth Eu3+ ion and the strongest emission band was narrow which was attributed to the 5 D0 --> 7 F2 transitions of the 4f electrons of the central Eu3+ ions. So, the new Eu(III) ternary complex is an excellent red-emitter which would be regarded as a valuable material with bright red fluorescence because it presents good monochromaticity.

10.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 15(3): 135-8, 2003 Mar.
Artículo en Chino | MEDLINE | ID: mdl-12831612

RESUMEN

OBJECTIVE: To verify that CD14(+) monocyte human leukocyte antigen DR (HLA-DR) may serve as a reliable index for immunosupression, and for prediction of prognosis as well as to evaluate the efficacy of Thymopentin (TP-5) to enhance immunologic function in patients with severe sepsis, and to evaluate the validity of compensatory anti-inflammatory response syndrome (CARS). METHODS: Patients in a SICU with symptoms and signs of severe sepsis conforming to the criteria set forth by ACCP/SCCM were enrolled in this clinical trial. CD14(+) monocyte HLA-DR was determined by flow cytometry. To those with HLA-DR<30%, TP-5, 1 mg, q.d. was administered till HLA-DR raised or death occurred. Before the treatment was begun and ended, CD14(+) monocyte HLA-DR(+) and cytokines[tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-10, IL-13] were respectively measured. RESULTS: Totally, 20 patients were enrolled in this study. Among them 15 survived and 5 died. After treatment with TP-5, CD14(+) monocyte HLA-DR was elevated in almost all the patients, including the nonsurvivors. However, only a statistically significant difference between the initial values and the final values was noted in the survivors. The levels of TNF-alpha and IL-6 dropped significantly concomitantly with the elevation of the CD14(+) monocyte HLA-DR in survivors. On the contrary, in the patients who died there was a tendency of an elevation of levels of these cytokines. No significant difference was found between the initial and final levels of both IL-10 and IL-13 with the treatment. CONCLUSION: 1. It was reconfirmed that the CD14(+) monocyte HLA-DR could be a reliable and valuable index to judge immunosupression in septic patients and determine the effectiveness of immunostimulative therapy. 2. It was reconfirmed that the level of CD14(+) monocyte HLA-DR can serve as an index to predict the outcome of septic patients. 3. TP-5, as a new immunostimulative agent used in sepsis, might be effective to revert immunosupression. However, a further clinical trial with a larger number of patients and a better control should be done to finally verify it. 4. It is found that immunosupression do not seem to be related with the balance between pro- and anti-inflammatory cytokines, suggesting that the hypothesis of CARS should be further appraised.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Antígenos HLA-DR/análisis , Monocitos/inmunología , Sepsis/inmunología , Timopentina/uso terapéutico , Biomarcadores/análisis , Humanos , Interleucina-13/análisis , Interleucina-6/análisis , Receptores de Lipopolisacáridos/inmunología , Pronóstico , Reproducibilidad de los Resultados , Sepsis/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/análisis
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