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1.
Front Plant Sci ; 13: 1003728, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36388522

RESUMEN

It is of great significance to study the nutritional characteristics of plants. Further understanding of plant mineral nutrient dynamics can provide theoretical basis for scientific fertilization to improve fruit quality and yield. In this study, eight mineral elements (N, P, K, Ca, Mg, Mn, Zn, B) were measured at regular intervals in leaves and kernels of the pecan "Mahan" planted in southern China. The study discussed the characteristics of mineral nutrient dynamics of pecan through the indicators of concentration, accumulation and cumulative relative rate, a new first proposed indicator, and focused on critical time, intensity, amount of mineral nutrients required in pecan during the fruit developing period, as well as the transfer information of the elements in leaves and kernels. The results show that the mineral nutrient requirements of the leaves and kernels are not identical, with an upward trend in nutrient accumulation within the kernel. The most abundant mineral nutrients in the leaves and kernels were N, K and Ca with Ca being greater than N in leaves. In particular, the concentration of Mn in pecan 'Mahan' is higher than that of other plants, and its Mg content is also higher than that of P in kernels. The dynamic changes of mineral nutrients in walnut showed obvious stages, with a trend of "slow (before mid-July) - fast (mid-July to late August) - slow (late August to late September) - fast (late September to harvest)". The "critical period" of kernels was before mid-July, during which the cumulative relative rates increased rapidly, indicating that the kernels had a great potential to absorb mineral nutrients. Significant accumulation of mineral nutrients occurred from mid-July to late August and late September to the end.

2.
Anal Chem ; 92(21): 14309-14313, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33138379

RESUMEN

Fractionation information on arsenic (As) in complex samples, particularly solid samples, is of immense interest. Herein, selective extraction of various As species adsorbed onto ferrihydrite as the model substrate was online-adapted to inductively coupled plasma-mass spectrometry (ICP-MS) for sensitive detection. The As-adsorbed ferrihydrite sample was loaded into a homemade online sequential elution device using two commercially available micropipette tips, and then, each fraction of As including nonspecifically adsorbed, specifically adsorbed, iron oxide bonded, and residual species was successively extracted for ICP-MS detection, with H2O, NH4NO3, NH4H2PO4, ammonium oxalate, and HF as the eluents, respectively. While no water-soluble As was detected, the fraction of As bonded to iron oxide was detected as the dominant species (>80%), and the specifically adsorbed As and residual As also accounted for a substantial amount (10%). The method had a detection limit of 0.008 µg/kg for As(III) and 0.013 µg/kg for As(V), with merits such as extremely low sample consumption, high throughput, and minimized experimental manipulation, presenting an alternative strategy for sensitive fractionation analysis of As adsorbed onto solid substrates (e.g., iron oxides, etc.).


Asunto(s)
Arsénico/análisis , Arsénico/aislamiento & purificación , Fraccionamiento Químico/métodos , Compuestos Férricos/química , Espectrometría de Masas , Adsorción , Arsénico/química , Límite de Detección , Propiedades de Superficie
3.
Sci Rep ; 9(1): 19279, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31848445

RESUMEN

In this work an on-line monitoring method was developed to study the mechanism of acetic acid catalyzed reaction between aniline and acetonylacetone using extractive electorspray ionization-tandem mass spectrometry (EESI-MS). The signals of reactants, intermediates and various byproducts were continuously detected as a function of reaction time. The chemical assignment of each signal was done via multi-stage collision induced dissociation (CID) analysis, and the reaction mechanism between aniline and acetonylacetone was deduced based on the generated molecular ions and fragment ions. The results indicate that on-line EESI-MS is an effective technique for the real time analysis of chemical reactions. EESI avoids off-line sample pretreatment and provides "soft" ionization, which allows direct analysis of various analytes at molecular level.

4.
Anal Bioanal Chem ; 411(15): 3281-3290, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30989270

RESUMEN

Quantification of ultra-trace analytes in complex biological samples using micro-solid-phase extraction followed by direct detection with internal extractive electrospray ionization mass spectrometry (µSPE-iEESI-MS) was demonstrated. 1-Hydroxypyrene (1-OHP) and papaverine at attomole levels in human raw urine samples were analyzed under negative and positive ion detection mode, respectively. The µSPE was simply prepared by packing a disposable syringe filter with octadecyl carbon chain (C18)-bonded micro silica particles, which were then treated as the "bulk sample" after the analytes were efficiently enriched by the C18 particles. Under the optimized experimental conditions, the analytes were readily eluted by isopropanol/water (80/20, V/V) at a high voltage of ± 4.0 kV, producing analyte ions under ambient conditions. The limit of detection (LOD) was 0.02 pg/L (9.2 amol) for 1-hydroxypyrene and 0.02 pg/L (5.9 amol) for papaverine. The acceptable linearity (R2 > 0.99), signal stability (RSD ≤ 10.7%), spike recoveries (91-95%), and comparable results for real urine samples were also achieved, opening up possibilities for quantitative analysis of trace compounds (at attomole levels) in complex bio-samples. Graphical abstract.


Asunto(s)
Papaverina/orina , Pirenos/orina , Microextracción en Fase Sólida/instrumentación , Espectrometría de Masa por Ionización de Electrospray/instrumentación , Vasodilatadores/orina , Adsorción , Biomarcadores/orina , Diseño de Equipo , Humanos , Límite de Detección , Papaverina/aislamiento & purificación , Pirenos/aislamiento & purificación , Reproducibilidad de los Resultados , Microextracción en Fase Sólida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/instrumentación , Espectrometría de Masas en Tándem/métodos , Vasodilatadores/aislamiento & purificación
5.
Inorg Chem ; 56(24): 14880-14887, 2017 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-29215269

RESUMEN

Reactions of La(NO3)3·6H2O with the polar, tritopic quaternized carboxylate ligands N-carboxymethyl-3,5-dicarboxylpyridinium bromide (H3CmdcpBr) and N-(4-carboxybenzyl)-3,5-dicarboxylpyridinium bromide (H3CbdcpBr) afford two water-stable metal-organic frameworks (MOFs) of {[La4(Cmdcp)6(H2O)9]}n (1, 3D) and {[La2(Cbdcp)3(H2O)10]}n (2, 2D). MOFs 1 and 2 absorb the carboxyfluorescein (FAM)-tagged probe DNA (P-DNA) and quench the fluorescence of FAM via a photoinduced electron transfer (PET) process. The nonemissive P-DNA@MOF hybrids thus formed in turn function as sensing platforms to distinguish conservative linear, single-stranded RNA sequences of Sudan virus with high selectivity and low detection limits of 112 and 67 pM, respectively (at a signal-to-noise ratio of 3). These hybrids also exhibit high specificity and discriminate down to single-base mismatch RNA sequences.


Asunto(s)
Ebolavirus/aislamiento & purificación , Fiebre Hemorrágica Ebola/virología , Lantano/química , Estructuras Metalorgánicas/química , ARN Viral/análisis , Secuencia de Bases , Cristalografía por Rayos X , Fluoresceínas/química , Colorantes Fluorescentes/química , Fiebre Hemorrágica Ebola/diagnóstico , Humanos , Límite de Detección , Modelos Moleculares , Espectrometría de Fluorescencia/métodos
6.
Zhongguo Zhong Yao Za Zhi ; 42(18): 3509-3515, 2017 Sep.
Artículo en Chino | MEDLINE | ID: mdl-29218935

RESUMEN

Tobacco black shank is one of the most harmful soil-borne diseases infected by Phytophthora parasitica. In order to probe the control method to this disease, in this study, the mycelial growth rate method was employed to investigate the antifungal effects of extracts from stem-leaf and root, root exudates, and their combination of Scrophularia ningpoensis, Chuanmingshen violaceum and Pinellia ternata The results showed that: ①Stem-leaf and root extracts of S. ningpoensis, C. violaceum and P. ternata exhibited different antifungal activities, and the inhibition increased with the increase of extract concentration. The antifungal effect of S. ningpoensis extracts at 0.5 g•mL⁻¹ was the strongest than other medicinal plants, the inhibition rate of steam-leaf and root extracts reached 74.88%, 69.27%, respectively. The inhibitory effect of C. violaceum and P. ternata was relatively lower, however, there is a significant gain effect after combination of steam-leaf and root extracts of C. violaceum. ②The root exudates of S. ningpoensis, C. violaceum and P. ternata showed fungistasis to Phytophthora nicotianae, and fungistasis was enhanced with the increase of root exudate concentration. The antifungal effect in the order of C. violaceum > S. ningpoensis > P. ternata. ③The antifungal activity of combination of extract and root exudate from S. ningpoensis was similar with the effect of C. violaceum, they were both stronger than P. ternata, and the antifungal activity for three combination were located between the antifungal activity of their extracts and root exudates. S. ningpoensis and C. violaceum can be potentially applied to prevent and control the tobacco black shank.


Asunto(s)
Fungicidas Industriales/farmacología , Fitoquímicos/farmacología , Phytophthora/efectos de los fármacos , Extractos Vegetales/farmacología , Apiaceae/química , Pinellia/química , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Exudados de Plantas/farmacología , Hojas de la Planta/química , Raíces de Plantas/química , Scrophularia/química
7.
Pak J Pharm Sci ; 29(5): 1695-1701, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27731831

RESUMEN

Aucklandialappa Decne (ALD) is one of the traditional herbs to treat various kinds of disorders including asthma, cough, vomit, diarrhea, hepatitis and cholecystitis. However, its effects on indigestion and particularly antiulcer activity of ethanol extract have not been studied. In the study, the Aucklandia lappa Decne extract (ALDE) was investigated to see if it againstgastric injury effects through traditional pathways. Ethyl alcohol and epinephrine hydrochloride were used to induce acute gastric mucous membrane damage in adult SD rats and Kunming mice, respectively. This present study evaluated its effects on peptic ulcer of ALDE treatment in SD rats and Kunming mice. In acute gastric mucous membrane damage induced by ethyl alcohol in rats, the results indicated that three ALDE treatment groups highly significantly decreased the mucosal damage index as compared to the model group. Furthermore, this mucosal damage index of the mid-dose group significantly decreased while the high-range dose group highly significantly decreased, respectively, as compared to the SO group. The ulcer inhibition rate of low -dose, mid-dose and high-dose ALDE treatment groups reached 68.64%, 72.67% and 74.91%, respectively. In acute gastric mucous membrane damage induced by pyloric ligation in rats, the results indicated that three ALDE treatment groups highly significantly decreased the mucosal damage index as compared to the model group. The mucosal damage index of middose group significantly decreased while the high-range dose group highly significantly decreased, respectively as compared to the SO group. The ulcer inhibition rate of low-dise, mid-dose and high-dose ALDE treatment groups reached 68.64%, 72.67% and 74.91%, respectively. In acute gastric mucous membrane damage induced by pyloric ligation in rats, the results indicated that three ALDE treatment groups highly significantly decreased the mucosal damage index of, respectively, as compared to the model group. Furthermore, this mucosal damage index of the midrange dose group significantly decreased while the high-dose group highly significantly decreased, respectively, as compared to the SO group. The ulcer inhibition rate of low-dose, mid-dose and high-dose ALDE treatment groups reached 68.64%, 72.67% and 74.91%, respectively. Our results indicated that ALDE exhibits a marked effect on peptic ulcer activity in animals, which supports previous results of its use in traditional Chinese medicine.


Asunto(s)
Antiulcerosos/farmacología , Mucosa Gástrica/efectos de los fármacos , Extractos Vegetales/farmacología , Úlcera Gástrica/prevención & control , Animales , Antiulcerosos/aislamiento & purificación , Citoprotección , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Epinefrina , Etanol , Femenino , Mucosa Gástrica/patología , Ligadura , Masculino , Ratones , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Píloro/cirugía , Ratas Sprague-Dawley , Saussurea/química , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/patología
8.
Artículo en Inglés | MEDLINE | ID: mdl-27529262

RESUMEN

Exposure to malachite green (MG) may pose great health risks to humans; thus, it is of prime importance to develop fast and robust methods to quantitatively screen the presence of malachite green in water. Herein the application of extractive electrospray ionization mass spectrometry (EESI-MS) has been extended to the trace detection of MG within lake water and aquiculture water, due to the intensive use of MG as a biocide in fisheries. This method has the advantage of obviating offline liquid-liquid extraction or tedious matrix separation prior to the measurement of malachite green in native aqueous medium. The experimental results indicate that the extrapolated detection limit for MG was ~3.8 µg·L(-1) (S/N = 3) in lake water samples and ~0.5 µg·L(-1) in ultrapure water under optimized experimental conditions. The signal intensity of MG showed good linearity over the concentration range of 10-1000 µg·L(-1). Measurement of practical water samples fortified with MG at 0.01, 0.1 and 1.0 mg·L(-1) gave a good validation of the established calibration curve. The average recoveries and relative standard deviation (RSD) of malachite green in lake water and Carassius carassius fish farm effluent water were 115% (6.64% RSD), 85.4% (9.17% RSD) and 96.0% (7.44% RSD), respectively. Overall, the established EESI-MS/MS method has been demonstrated suitable for sensitive and rapid (<2 min per sample) quantitative detection of malachite green in various aqueous media, indicating its potential for online real-time monitoring of real life samples.


Asunto(s)
Acuicultura , Colorantes de Rosanilina/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Agua/química , Animales , Humanos , Límite de Detección , Reproducibilidad de los Resultados
9.
Pak J Pharm Sci ; 29(4): 1243-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27393424

RESUMEN

Using the serum pharmacochemistry method for Chinese Medicine, the material basis of Radix Astragali (RA) for "regulating and enriching blood" was studied. By compared with blank blood sample as a positive control in adult Wistar rats, four original saponinsas the material basis for "regulating and enriching blood" were absorbed into the blood after oral administration of RA. They were identified as astragaloside, astragaloside, astragaloside and astragaloside by HPLC-MS. According to the constituents absorbed into blood, the extracts of RA were prepared. In addition, the present patterns of quality control are limited to industrial application because most of the natural standard ingredients are very expensive and unavailable. Therefore, a quantitative analysis method of multi-components with a single marker (QAMS) was established and used to simultaneously measure four saponins from RA absorbed into the blood (Astragaloside, astragaloside, astragaloside and astragaloside). We used astragaloside I as the reference, the relative correction factors (f) of the other three saponins were measured by HPLC-MS. Within the linear ranges, the values of f of astragaloside I to astragaloside IV, astragaloside III and astragaloside II were 0.533, 0.779 and 0.934, respectively. According to the f values, we simultaneously determined four saponins using only one marker. The results of QAMS method were validated compared to that of external standard method, and no significant difference was observed.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Animales , Astragalus propinquus , Espectrometría de Masas , Extractos Vegetales/análisis , Ratas , Ratas Wistar
10.
Anal Chim Acta ; 922: 55-63, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27154832

RESUMEN

Coordination reaction of a known three-dimensional (3D) polymer precursor {Na3[Na9(Cbdcp)6(H2O)18]}n (A, Cbdcp = N-(4-carboxybenzyl)-(3,5-dicarboxyl)pyridinium) with Zn(NO3)2·6H2O in H2O or H2O/DMF at 100 °C and in the presence of aspirin, 5-fluorouracil (5-FU) as modulators, trans-1,2-bis(4-pyridyl)ethylene (bpe) or 1,2-bis(4-pyridyl)ethane (bpea) as ancillary ligands afforded six novel Zn(II)-based metal-organic frameworks (MOFs), that is, {[Zn(Cbdcp)(H2O)3]·H2O}n (1, 1D zigzag chain), {[Zn(HCbdcp)2]·H2O}n (2, 2D sheet), {[Zn(Cbdcp)(bpe)1/2]·2H2O}n (3, 3D polymer), {[Zn(Cbdcp)(bpe)1/2]·2H2O}n (4, 2D network), {[Zn(Cbdcp)(bpea)1/2]·2H2O}n (5, 3D polymer) and {[Zn(Cbdcp)(bpea)1/2]·2H2O}n (6, 2D network). Among them, compound 2 contains aromatic rings, positively charged pyridinium, Zn(2+) cation centers and carboxylic acid groups lined up on the 2D sheet structure with a certain extended surface exposure. The unique structure of 2 facilitates effective association with carboxyfluorescein (FAM) labeled probe single stranded DNA (probe ss-DNA, delineates as P-DNA) to yield a P-DNA@2 system, and leads to fluorescence quenching of FAM via a photoinduced electron transfer process. The P-DNA@2 system is effective and reliable for the detection of human immunodeficiency virus 1 ds-DNA (HIV ds-DNA) sequences and capable of distinguishing complementary HIV ds-DNA from mismatched target sequences with the detection limit as low as 10 pM (S/N = 3).


Asunto(s)
ADN Viral/análisis , VIH-1/genética , Zinc/química , Complejos de Coordinación/química , Difracción de Polvo , Análisis Espectral/métodos , Termogravimetría
11.
Dalton Trans ; 45(12): 5092-100, 2016 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-26883749

RESUMEN

Polymorphic compounds {[Cu(dcbb)2(H2O)2]·10H2O}n (2, 1D chain), [Cu(dcbb)2]n (3, 2D layer) and their co-crystal {[Cu(dcbb)2(H2O)][Cu(dcbb)2]2}n (4) have been prepared from the coordination reaction of a 2D polymer [Na(dcbb)(H2O)]n (1, H2dcbbBr = 1-(3,5-dicarboxybenzyl)-4,4'-bipyridinium bromide) with Cu(NO3)2·3H2O at different temperatures in water. Compounds 2-4 have an identical metal-to-ligand stoichiometric ratio of 1 : 2, but absolutely differ in structure. Compound 3 features a 2D layer structure with aromatic rings, positively charged pyridinium and free carboxylates on its surface, promoting electrostatic, π-stacking and/or hydrogen-bonding interactions with the carboxyfluorescein (FAM) labeled probe single-stranded DNA (probe ss-DNA, delineates as P-DNA). The resultant P-DNA@3 system facilitated fluorescence quenching of FAM via a photoinduced electron transfer process. The P-DNA@3 system functions as an efficient fluorescent sensor selective for HIV double-stranded DNA (HIV ds-DNA) due to the formation of a rigid triplex structure with the recovery of FAM fluorescence. The system reported herein also distinguishes complementary HIV ds-DNA from mismatched target DNA sequences with the detection limit of 1.42 nM.


Asunto(s)
ADN/química , VIH/genética , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Cobre/química , Cristalografía por Rayos X , ADN/metabolismo , Fluoresceínas/química , Enlace de Hidrógeno , Conformación Molecular , Polímeros/química , Espectrometría de Fluorescencia
12.
Chem Commun (Camb) ; 52(1): 132-5, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26502791

RESUMEN

We herein report a water-stable 3D dysprosium-based metal-organic framework (MOF) that can non-covalently interact with probe ss-DNA. The formed system can serve as an effective fluorescence sensing platform for the detection of complementary Ebolavirus RNA sequences with the detection limit of 160 pM.


Asunto(s)
Disprosio/química , Ebolavirus/aislamiento & purificación , Colorantes Fluorescentes/química , Fiebre Hemorrágica Ebola/diagnóstico , Compuestos Organometálicos/química , ARN Viral/análisis , Secuencia de Bases , Cristalografía por Rayos X , Sondas de ADN/química , Sondas de ADN/genética , Ebolavirus/genética , Fiebre Hemorrágica Ebola/virología , Humanos , Límite de Detección , Modelos Moleculares , ARN Viral/genética , Espectrometría de Fluorescencia/métodos , Agua/química
13.
Zhongguo Zhong Yao Za Zhi ; 41(24): 4556-4563, 2016 Dec.
Artículo en Chino | MEDLINE | ID: mdl-28936837

RESUMEN

Soil microbes are the important indicator of soil quality. For exploring Chuanminshen violaceum planting to microbial effects in tobacco soil, this paper adopted Illumina MiSeq high-throughput sequencing to research the change of bacteria and fungi at the phylum and genus in the soil. The results showed that the Ch. violaceum planting increased the biodiversity of bacteria and fungi. The influence on fungi was greater than that on bacteria. It greatly increased the sequence of fungi, it obtained 32 978 16S rDNA and 32 229 18S rDNA sequence number. There was no change of the top three phylums in bacteria, but the content changed, Proteobacteria and Acidobacteria reduced by 1.73% and 1.4% respectively, and Actinobacteria increased by 0.65%. The advantage phylum Ascomycete in tobacco reduced by 27.99% to be second advantage phylum after Ch. violaceum planting, and the second advantage phylum Basidiomycete increased by 23.69% to become the first dominant fungi. At the genus, Ch. violaceum planting changed the order of dominant genus and the abundance was also changed. Some changed largely such as uncultured Acidobacteriaceae Subgroup-1, Gemmatimonas, Subgroup-2,uncultured Nitrosomonadaceae for bacteria, norank Sordariales, norank Agaricomycetes, Phialophora for fungi. Especially the rotation increased antagonistic microbes and physiological microbes and decreased pathogenic microbes. So the Ch. violaceum planting can improve the microbe community in tobacco soil.


Asunto(s)
Agricultura/métodos , Apiaceae/crecimiento & desarrollo , Nicotiana/crecimiento & desarrollo , Microbiología del Suelo , Apiaceae/microbiología , Bacterias/clasificación , Biodiversidad , Hongos/clasificación , ARN Ribosómico 16S , Suelo , Nicotiana/microbiología
14.
Zhongguo Zhong Yao Za Zhi ; 41(10): 1803-1810, 2016 May.
Artículo en Chino | MEDLINE | ID: mdl-28895324

RESUMEN

In this study, several types of Artemisia annua in soil, including the soil which had not been planted, or planted for one year, or continuously planted for three or five years were collected, in order to study the influences of continuous cropping on the growth of A. annua, content of artemisinin, available nutrient of soil, and bacterial community structure through adopting routine analysis and Illumina MiSeq high-throughput sequencing. The results showed that continuous cropping inhibited significantly the growth of A. annua and reduced leaf biomass, content and yield of artemisinin, with the maximum decreasing amplitude of 30.20%, 7.70% and 35.58% respectively. The content of soil organic matter, available nitrogen, available phosphorus and 16S rRNA sequence number were increased to different extents after continuous cropping of A. annua. According to the results of high-throughput sequencing, 634-812 types of common bacteria belonged to 21 categories were planted in different soil of A. annua with different planting years, which represented that the distribution distance of the point of bacterial community with different years among coordinate system of principal component was relative distant, and community structure had significant changes (P<0.05). As the planting years increased, the abundance of Actinobacteria, Chloroflexi, Gemmatimonadetes decreased in contrast to Proteobacteria, Acidobacteria and Verrucomicrobia. In the top 20 types of predominant bacteria,Nitrospira japonica and Nitrospira disappeared, among which, only Gemmatimonadaceae, Micromonosporaceae, Nitrosomonadaceae, Xanthobacteraceae, and unculture bacterium JG30-KF-AS9 were similar, indicating that the planting and continuous cropping of A. annua selectively inhibited the growth and reproduction of soil bacteria, and influenced the supply and transform of soil nutrient, leading to a poor growth and resulting in reduction of artemisinin content and yield. Therefore, it is necessary to advocate crop rotation in the process of planting A. annua.


Asunto(s)
Agricultura/métodos , Artemisia annua/crecimiento & desarrollo , Bacterias/clasificación , Microbiología del Suelo , Artemisia annua/química , Artemisininas/análisis , ARN Ribosómico 16S
15.
Anal Chem ; 87(24): 12206-14, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26619043

RESUMEN

We herein report a water-stable three-dimensional Cu-based metal-organic framework (MOF) 1 supported by a tritopic quaternized carboxylate and 4,4'-dipyridyl sulfide as an ancillary ligand. This MOF exhibits unique pore shapes with aromatic rings, positively charged pyridinium and unsaturated Cu(II) cation centers, free carboxylates, tessellating H2O, and coordinating SO4(2-) on the pore surface. Compound 1 can interact with two carboxyfluorescein (FAM)-labeled single-stranded DNA sequences (probe ss-DNA, delineated as P-DNA) through electrostatic, π-stacking, and/or hydrogen-bonding interactions to form two P-DNA@1 systems, and thus quench the fluorescence of FAM via a photoinduced electron-transfer process. These P-DNA@1 systems can be used as effective fluorescent sensors for human immunodeficiency virus 1 double-stranded DNA and Sudan virus RNA sequences, respectively, with detection limits of 196 and 73 pM, respectively.


Asunto(s)
Técnicas Biosensibles , Cobre/química , ADN de Cadena Simple/análisis , ADN Viral/análisis , Colorantes Fluorescentes/química , Compuestos Organometálicos/química , ARN Viral/análisis , Cristalografía por Rayos X , Ebolavirus/química , VIH-1/química , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química
16.
Dalton Trans ; 44(29): 13369-77, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26131732

RESUMEN

Five water-soluble zwitterionic copper-carboxylate polymers were prepared from the reaction of N-carboxymethyl-(3,5-dicarboxyl)pyridinium bromide (H3CmdcpBr) with Cu(NO3)2 in the presence of NaOH by modulating the temperature, solvent and ancillary dipyridyl ligands. These complexes include a 1D ladder-shaped polymer {[Cu3(Cmdcp)2(OH)2(H2O)2]·H2O}n () formed in H2O at room temperature, and a 2D network polymer {[Cu(Cmdcp) (H2O)2]·2H2O}n () isolated in H2O at 135 °C. At 100 °C in H2O/DMF, the same reaction in the presence of an additional 2,2'-bipyridine (bipy) gave a 2D zwitterionic complex {[Cu(Cmdcp)(bipy)]·3H2O}n () together with a 1D double-stranded polymer {[Cu(Cmdcp)(H2O)2]·H2O}n () as a minor product. The replacement of bipy with phenanthroline (phen) afforded a 1D zigzag polymer chain {[Cu(Cmdcp)(phen)(H2O)]2·9H2O}5 (). All these complexes were characterized by IR, elemental analyses and single crystal X-ray crystallography. Agarose gel electrophoresis (GE) and ethidium bromide (EB) displacement experiments indicated that complex exhibited the highest pBR322 DNA cleaving ability with the catalytic efficiency (kmax/KM) of 14.80 h(-1) mM(-1) and the highest binding affinity toward calf-thymus DNA. The MTT assay indicated that complex showed significant inhibitory activity toward the proliferation of several tumor cells. Its IC50 value was at micromolar level and lower than those of cisplatin and complexes , especially toward resistant lung adenocarcinoma cell A549.


Asunto(s)
2,2'-Dipiridil/química , Antineoplásicos/química , Ácidos Carboxílicos/química , Cobre/química , División del ADN/efectos de los fármacos , Polímeros/química , 2,2'-Dipiridil/farmacología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Animales , Antineoplásicos/farmacología , Ácidos Carboxílicos/farmacología , Bovinos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cobre/farmacología , Cristalografía por Rayos X , ADN/química , ADN/metabolismo , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Modelos Moleculares , Polímeros/farmacología , Solubilidad , Agua/química
17.
Mol Med Rep ; 12(1): 1145-50, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25776802

RESUMEN

Previous studies have revealed that high levels of serum homocysteine (Hcy) are closely associated with the development of juvenile and age-related cataracts. An increased concentration of Hcy is likely to induce gene specific demethylation in DNA promoter regions. The aim of the present study was to prevent this demethylation by administering acetyl-l-carnitine (ALCAR) to human lens epithelial cells (HLECs). Different concentrations of Hcy were used to treat HLECs for 3, 6, 12 and 24 h and the findings were used to determine the optimum dose to induce endoplasmic reticulum (ER) stress. Similarly, the concentration of ALCAR was standardized. The production of reactive oxygen species (ROS) and the percentage of cells undergoing cell death were measured. The levels of antioxidants, ER stress-associated proteins, mRNA levels of nuclear factor erythroid-2-related factor 2 (Nrf2), Kelch-like ECH-associated protein 1 (Keap1) and promoter DNA methylation of the Keap1 gene were also assessed. Hcy was observed to induce ER stress, produce ROS and lead to cell death. However, administration of ALCAR prevented these effects to a significant degree. Additionally, western blot analysis revealed that ALCAR increased the levels of antioxidant proteins, including catalase, superoxide dismutase, glutathione peroxidase, Nrf2, Keap1 and glutathione. Similarly, the reverse transcription-quantitative polymerase chain reaction experiments on Nrf2 and Keap1, as well as the bisulfite genomic DNA sequencing analysis revealed a preventive effect of ALCAR against Hcy-induced ER stress. The ER stress-induced activation of the unfolded protein response is responsible for demethylation of Keap1 promoter DNA to activate the expression of the Keap1 protein, which then increases the targeting of Nrf2 for proteosomal degradation. This decrease in Nrf2 activity represses the transcription of numerous antioxidant enzyme genes and alters the redox-balance towards lens oxidation. However, treatment with ALCAR led to significant protection from these effects. The present results suggested that ALCAR either prevents or ameliorates the actions of the antioxidant system in HLECs at the level of the protein and the gene. Further advanced studies are required for the development of ALCAR as an anti-cataract agent.


Asunto(s)
Acetilcarnitina/farmacología , Antioxidantes/farmacología , Homocisteína/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Cristalino/efectos de los fármacos , Factor 2 Relacionado con NF-E2/genética , Animales , Catalasa/genética , Catalasa/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular , Metilación de ADN/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Epigénesis Genética , Glutatión/metabolismo , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Homocisteína/farmacología , Humanos , Péptidos y Proteínas de Señalización Intracelular/agonistas , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch , Cristalino/citología , Cristalino/metabolismo , Factor 2 Relacionado con NF-E2/agonistas , Factor 2 Relacionado con NF-E2/antagonistas & inhibidores , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Regiones Promotoras Genéticas/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis/efectos de los fármacos , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Transcripción Genética
18.
Iran J Pharm Res ; 13(4): 1191-201, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25587307

RESUMEN

The aim of this paper is to develop a rapid and highly sensitive quantitative HPLC fingerprint method with multiple indicators by using the Compound Chinese Medicine Wuwei Changyanning granule and 5 herbs in the prescription. The quantitative fingerprint chromatogram with multiple indicators was investigated. і)6 compositions included rutin, gallic acid, chlorogenic acid, atractylenolide Ⅰ, pachymic acid and apigenin, which originated from 5 herbs respectively, were selected as quantitative compositions, and their contents were determined using HPLC from 11 batches granules and the corresponding 5 medicinal materials. ⅱ) The precision, stability and repeatability of fingerprinting were investigated. In addition, common peaks number, the percentage of non-common peaks and similarity were also studied. Among them, 21 common peaks in the granule could find the source of peaks from the 5 herbs, among of 10 peaks from Niuerfeng, 9 peaks from Laliao, 3 peaks from Baishu, 3 peaks from Fuling and 5 peaks from Guanghuoxiang. The results showed that the identification method of fingerprinting was reliable.

19.
Phytomedicine ; 21(5): 640-6, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24290471

RESUMEN

To investigate the pharmacological effects of Danggui Buxue Tang (DBT) on immune-mediated aplasia anemia mice. The model of immune-mediated aplasia anemia mice was induced by means of (60)Co γ-ray irradiation and mixed cells of thymus and lymphnode of DBA/2 mice infusion through tail vein, the parameters tested indices were as following: blood picture, bone marrow nucleated cell count (BMNC), murine colony-forming unit-megakaryocytes (CFU-GM) of bone marrow cells, murine colony-forming unit-erthroid (CFU-E) and burst forming unit-erythroid (BFU-E). The results showed that DBT could not only withstand significantly decreation of blood cells by immune-mediated, but also stimulate on the growth of bone marrow colony cell and increase the weight of hemopoietic progenitor of bone marrow. Therefore, DBT had an obvious treat effect on immune-mediated aplasia anemia models mice.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Médula Ósea/efectos de los fármacos , Medicamentos Herbarios Chinos/uso terapéutico , Fitoterapia , Animales , Médula Ósea/inmunología , Médula Ósea/patología , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Femenino , Masculino , Ratones Endogámicos BALB C , Distribución Aleatoria
20.
Pak J Pharm Sci ; 26(6): 1173-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24191323

RESUMEN

In the present study, the antibacterial tests of herba pogostemonis oil were studied by using molecular- docking technology and antibacterial test in vitro. The 3 three-dimensional (3D) structures of the 5 compared compositions and 26 compositions from herba pogostemonis oil were established by using surflex-dock software (8.1). Molecular-docking was carried out between the 31 chemical compositions (ligands) and the 5 enzymes (receptors) by using surflex-dock function. By comparing the scoring result of 26 compositions in herba pogostemonis oil with 5 compared components, we can infer antibacterial activity about 26 compositions in herba pogostemonis oil. On the other hand, six frequently-used pathogenic bacteria were selected for antimicrobial test in vitro, herba pogostemonis oil and its two major compositions: (-)-herba pogostemonis alcohol and pogostone, which their contents exceeded 60% in herba pogostemonis oil samples, were selected antibacterial agents. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) were also determined. Molecular-docking technology and antimicrobial test in vitro all were proved that herba pogostemonis oil had strong antibacterial effects. Particularly, pogostone and (-)-herba pogostemonis alcohol have potent antimicrobial activity.


Asunto(s)
Antibacterianos/farmacología , Lamiaceae/química , Aceites Volátiles/farmacología , Medicina Tradicional China , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Aceites Volátiles/análisis
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